EP1343900A2 - Oxidoreductases - Google Patents

Abstract

The invention provides human oxidoreductases (OXRD) and polynucleotides which identify and encode OXRD. The invention also provides expression vectors, host cells, antibodies, agonists, and antagonists. The invention also provides methods for diagnosing, treating, or preventing disorders associated with aberrant expression of OXRD.

Description

OXIDOREDUCTASES

TECHNICAL FIELD

This invention relates to nucleic acid and amino acid sequences of oxidoreductases and to the use of these sequences in the diagnosis, treatment, and prevention of cell proliferative, neurological, metabolic, and smooth muscle disorders, and in the assessment of the effects of exogenous compounds on the expression of nucleic acid and amino acid sequences of oxidoreductases.

BACKGROUND OF THE INVENTION Eukaryotic cells extract energy and synthesize macromolecules by a complex series of oxidation-reduction reactions collectively referred to as aerobic metabolism. One consequence of aerobic metabolism is the production of free radicals in the form of superoxides (O₂ ^,_) and hydroxyl ions (OH-). Superoxides are produced within cells by mitochondria and the endoplasmic reticulum as a consequence of "leakage" of electrons onto O₂ from their correct paths in electron transfer chains. Hydroxyl ions are produced by ionizing radiation and by the reaction of 0₂ ^~ with hydrogen peroxide (HjO-z) at iron- or copper-containing sites. Free radicals, especially hydroxyl ions, are extremely reactive and can interact with almost all molecules, including proteins, carbohydrates, DNA, and lipids. These interactions can lead to the formation of nonradical hydroperoxides, such as phospholipid hydroperoxides. Interaction of hydroxyl ions with DNA may be a sigrrificant contributor to the age- dependent development of cancer. Cells also use free radicals and their derivatives in beneficial ways, such as cytochrome P450-mediated oxidations, regulation of smooth muscle tone, and killing of microorganisms by macrophages and granulocytes (Bast, A. et al. (1991) Am. J. Med. 91(3C):2S- 13S).

Defects in enzymes involved in oxidation and reduction reactions in cells (oxidoreductases) lead to imbalances in the oxidation potential within cells, frequently with clinical manifestations. For example, an excess of superoxide dismutase (SOD), an enzyme that detoxifies superoxide compounds, may be relevant to the clinical condition known as Down's Syndrome. Low antioxidant levels or high O₂ ^~ and H₂O₂ levels produce oxidative stress. Oxidative stress induced by phagocytes at sites of chronic inflammation lead to rheumatoid arthritis in the joints and inflammatory bowel diseases in the intestine. Asthma is also a manifestation of an inflammatory reaction in the lung and is related to oxygen free radical formation (Sies, H. (1991) Am. J. Med. 91 (3C):31S-38S).

Proteins involved in oxidation and reduction also have specific functions in synthesis, catalysis, salvage, and detoxification within cells. Defects in these enzymes are likely to lead to the accumulation of toxic precursor molecules within cells or the failure to synthesize compounds critical for cell viability (see examples, below). In addition to their activities on naturally occurring substrates, oxidoreductases are also closely associated with drug metabolism and pharmacokinetics. Inherited differences in drug metabolism lead to drastically different levels of drag efficacy and toxicity among individuals. For drags with narrow therapeutic indices, or drags which require bioactivation (such as codeine), these polymorphisms can be critical. Moreover, promising new drugs are frequently eliminated in clinical trials based on toxicities which may only affect a segment of the patient group. Advances in pharmacogenomics research, of which drag metabolizing enzymes constitute an important part, are promising to expand the tools and information that can be brought to bear on questions of drag efficacy and toxicity (Evans, W.E. and RN. Relling (1999) Science 286:487-491). The properties of selected oxidoreductases (i.e., glutathione peroxidases, glutathione S- transferase, glutaredoxin, peroxisomal β-oxidation enzymes, protein disulfide isomerases, thioredoxins, aldo/keto reductases, aldehyde dehydrogenases, alcohol dehydrogenases, acyl-CoA dehydrogenase, 6- phosphogluconate dehydrogenase, ribonucleotide diphosphate reductase, dihydrodiol dehydrogenase, 15-oxoprostaglandin 13-reductase, 15-hydroxyprostaglandin dehydrogenase, glucose-methanόl-choline oxidoreductases, and other secreted redox proteins) associated with acquired and inherited genetic diseases and drag metabolism, are described, below. Glutathione peroxidases

The family of glutathione peroxidases encompass three tetrameric glutathione peroxidases (GPxl -3) and the monomeric phospholipid hydroperoxide glutathione peroxidase (PHGPx/GPx4). Although the overall homology between tetrameric enzymes and GPx4 is less than 30%, a pronounced similarity has been detected in clusters involved in the active site and a common catalytic triad has been defined by structural and kinetic data (Epp, O. et al. (1983) Eur. J. Biochem. 133:51-69). The family members show different tissue distributions. GPxl is ubiquitously expressed in cells, whereas GPx2 is present in the liver and colon, and GPx3 is present in plasma. GPx4 is found at low levels in all tissues but is expressed at high level in the testis. These tissue localization patterns may be important for regulating the level and targets of glutathione peroxidase activity (Ursini, F. et al (1995) Meth. Enzymol. 252:38-53).

GPx4 is unique in both its structure and activity. GPx4 is the only monomeric glutathione peroxidase found in mammals. It is also the only mammalian glutathione peroxidase to show high affinity for and reactivity with phospholipid hydroperoxides, and to be membrane associated. The inhibition of lipid peroxidation by GPx4 requires glutathione and physiological levels of vitamin E, suggesting a tandem mechanism for the antioxidant activities of GPx4 and vitamin E. GPx4 also has alternative transcription and translation start sites which determine its subcellular localization (Esworthy, R.S. et al. (1994) Gene 144:317-318; and Maiorino, M. et al. (1990) Meth. Enzymol. 186:448-450).

Glutathione S-transferases (GST) The glutathione S-transferases (GST) are a ubiquitous family of enzymes with dual substrate specificities that perform important biochemical functions of xenobiotic biotransformation and detoxification, drug metabolism, and protection of tissues against peroxidative damage. The basic reaction catalyzed by these enzymes is the conjugation of an electrophile with reduced glutathione (GSH) and results in either activation or deactivation/detoxification of the chemical. The absolute requirement for binding reduced GSH to a wide variety of chemicals necessitates a diversity in GST structures in various organisms and cell types.

GSTs are homodimeric or heterodimeric proteins localized in the cell cytosol. The major isozymes share common structural and catalytic properties and, many have been classified into four major classes, Alpha, Mu, Pi, and Theta. The two largest classes, Alpha and Mu, are identified by their respective isoelectric points; pi ~ 7.5-9.0 (Alpha), and pi ~ 6.6 (Mu). Each GST possesses a common binding site for GSH and a variable hydrophobic binding site. The hydrophobic binding site in each isozyme is specific for particular electrophilic substrates. Specific amino acid residues within GSTs have been identified as important for these binding sites and for catalytic activity. Residues Q67, T68, D101, E104, and R131 are important for the binding of GSH (Lee, H.-C. et al. (1995) J. Biol. Chem. 270:99-109). Residues R13, R20, and R69 are important for the catalytic activity of GST (Stenberg, G. et al. (1991) Biochem. J. 274:549-555).

While GSTs normally perform the essential function of deactivation and detoxification of potentially mutagenic and carcinogenic chemicals, dysfunction or inappropriate expression of GSTs are detrimental. Some forms of rat and human GSTs are reliable preneoplastic markers of carcinogenesis. Expression of human GSTs in bacterial strains, such as Salmonella tvphimurium, used in the well known Ames test for mutagenicity, has helped to establish the role of these enzymes in mutagenesis. Dihalomethanes, which produce liver tumors in mice, are believed to be activated by GST. This view is supported by the finding that dihalomethanes are more mutagenic in transformed bacterial cells expressing human GST than in non-transformed cells (Thier, R. et al. (1993) Proc. Natl. Acad. Sci. USA 90:8567-8580). The mutagenicity of ethylene dibromide and ethylene dichloride is increased in bacterial cells expressing the human Alpha GST, Al-1, while the mutagenicity of aflatoxin Bl is substantially reduced by enhancing the expression of GST (Simula, T.P. et al. (1993) Carcinogenesis 14:1371-1376). Thus, control of GST activity may be useful in the control of mutagenesis and carcinogenesis.

GST has been implicated in the acquired resistance of many cancers to drug treatment, the phenomenon known as multi-drug resistance (MDR). MDR occurs when a cancer patient is treated with a cytotoxic drug such as cyclophosphamide and subsequently becomes resistant to this drag and to a variety of other cytotoxic agents as well. Increased GST levels are associated with some of these drag resistant cancers, and it is believed that this increase occurs in response to the drag agent which is then deactivated by the GST catalyzed GSH conjugation reaction. The increased GST levels then protect the cancer cells from other cytotoxic agents for which GST has affinity. Increased levels of Al-1 in tumors has been linked to drug resistance induced by cyclophosphamide treatment (Dirven, H.A. et al. (1994) Cancer Res. 54:6215-6220). Thus control of GST activity in cancerous tissues may be useful in treating MDR in cancer patients. Glutaredoxin

The reduction of ribonucleotides to the corresponding deoxyribonucleotides, needed for DNA synthesis during cell proliferation, is catalyzed by the enzyme ribonucleotide diphosphate reductase. Glutaredoxin is a glutathione (GSH)-dependent hydrogen donor for ribonucleotide diphosphate reductase and contains the active site consensus sequence -C-P-Y-C-. This sequence is conserved in glutaredoxins from such different organisms as E. coli. vaccinia virus, yeast, plants, and mammalian cells. Glutaredoxin has inherent GSH-disulfide oxidoreductase (thioltransferase) activity in a coupled system with GSH, NADPH, and GSH-reductase, catalyzing the reduction of low molecular weight disulfides as well as proteins. Glutaredoxin has been proposed to exert a general thiol redox control of protein activity by acting both as an effective protein disulfide reductase, similar to thioredoxin, and as a specific GSH-mixed disulfide reductase (Padilla, CA. et al. (1996) FEBS Lett. 378:69-73).

In addition to their important role in DNA synthesis and cell division, glutaredoxin and other thioproteins provide effective antioxidant defense against oxygen radicals and hydrogen peroxide (Schallreuter, K.U. and J.M. Wood (1991) Melanoma Res. 1:159-167). Glutaredoxin is the principal agent responsible for protein dethiolation in vivo and reduces dehydroascorbic acid in normal human neutrophils (Jung, CH. and J.A. Thomas (1996) Arch. Biochem. Biophys. 335:61-72; Park, J.B. and M. Levine (1996) Biochem. J. 315:931-938). Secreted redox proteins Redox polypeptides are also released into the extracellular environment and may have similar or distinct functions compared to their intracellular homologues. Several cytokines or secreted cytokine-like factors such as adult T-cell leukemia-derived factor, 3B6-interleukin-l, T-hybridoma- derived (MP-6) B cell stimulatory factor, and early pregnancy factor have been reported to be identical to thioredoxin (Holmgren, A. (1985) Annu. Rev. Biochem. 54:237-271; Abate, C. et al. (1990) Science 249:1157-1161 ; Tagaya, Y. et al. (1989) EMBO J. 8:757-764; Wakasugi, H. (1987) Proc. Natl. Acad. Sci. USA 84:804-808; Rosen, A. et al. (1995) Int. Immunol. 7:625-633). Thus thioredoxin secreted by stimulated lymphocytes (Yodoi, J. and T. Tursz (1991) Adv. Cancer Res. 57:381-411; Tagaya, N. et al. (1990) Proc. Natl. Acad. Sci. USA 87:8282-8286) has extraceUular activities including a role as a regulator of cell growth and a mediator in the immune system (Miranda- Vizuete, A. et al. (1996) J. Biol. Chem. 271 :19099-19103; Yamauchi, A. et al. (1992) Mol. Immunol. 29:263-270).

The selenoprotein thioredoxin reductase is secreted by both normal and neoplastic cells and has been implicated as both a growth factor and as a polypeptide involved in apoptosis (Soderberg, A. et al. (2000) Cancer Res. 60:2281-2289). An extracellular plasmin reductase secreted by hamster ovary cells (HT-1080) has been show to participate in the generation of angiostatin from plasmin. In this case, the reduction of the plasmin disulfide bonds triggers the proteolytic cleavage of plasmin which yields the angiogenesis inhibitor, angiostatin (Stathakis, P. et al. (1997) J. Biol. Chem. 272:20641 -20645). Low levels of reduced sulfhydryl groups in plasma has been associated with rheumatoid arthritis. The failure of these sulfhydryl groups to scavenge active oxygen species (e.g., hydrogen peroxide produced by activated neutrophils) results in oxidative damage to surrounding tissues and the resulting inflammation (Hall, N.D. et al. (1994) Rheumatol. Int. 4:35-38). Protein disulfide isomerases, thioredoxins. and glutaredoxins Cells contain a number of specialized molecules that assist in the formation of protein secondary and tertiary structure by orchestrating the formation of disulfide bonds. Although incubation of reduced, unfolded proteins in buffers with defined ratios of oxidized and reduced thiols can lead to native conformation, the rate of folding is slow and the attainment of native conformation decreases proportionately to the size and number of cysteines in the protein. Certain cellular compartments such as the endoplasmic reticulum of eukaryotes and the periplasmic space of prokaryotes are maintained in a more oxidized state than the surrounding cytosol. Correct disulfide formation can occur in these compartments but at a rate that is insufficient for normal cell processes and not adequate for synthesizing secreted proteins. The protein disulfide isomerases, thioredoxins and glutaredoxins are able to catalyze the formation of disulfide bonds and regulate the redox environment in cells to enable the necessary thiokdisulfide exchanges (Loferer, H. (1995) J. Biol. Chem. 270:26178-26183).

Each of these proteins have somewhat different functions but all belong to a group of disulfide-containing redox proteins that contain a conserved active-site sequence and are ubiquitously distributed in eukaryotes and prokaryotes. Protein disulfide isomerases are found in the endoplasmic reticulum of eukaryotes and in the periplasmic space of prokaryotes. They function by exchanging . their own disulfide for a thiol in a folding peptide chain. In contrast, the reduced thioredoxins and glutaredoxins are generally found in the cytoplasm and function by directly reducing disulfides in the substrate proteins.

These catalytic molecules not only facilitate disulfide formation but also regulate and participate in a wide variety of physiological processes. The thioredoxin system serves, for example, as a hydrogen donor for ribonucleotide reductase and as a regulator of enzymes by redox control. It also modulates the activity of transcription factors such as NF-κB, AP-1, and steroid receptors. Aldo/keto reductases

Aldo/keto reductases are monomeric NADPH-dependent oxidoreductases with broad substrate specificities (Bohren, K.M. et al. (1989) J. Biol. Chem. 264:9547-9551). These enzymes catalyze the reduction of carbonyl-containing compounds, including carbonyl-containing sugars and aromatic compounds, to the corresponding alcohols. Therefore, a variety of carbonyl-containing drags and xenobiotics are likely metabolized by enzymes of this class.

One known reaction catalyzed by a family member, aldose reductase, is the reduction of glucose to sorbitol, which is then further metabolized to fructose by sorbitol dehydrogenase. Under normal conditions, the reduction of glucose to sorbitol is a minor pathway. In hyperglycemic states, however, the accumulation of sorbitol is implicated in the development of diabetic complications (OMEVI *103880 Aldo-keto reductase family 1, member Bl). Members of this enzyme family are also highly expressed in some liver cancers (Cao, D. et al. (1998) J. Biol. Chem. 273:11429-11435). Aldehyde dehydrogenases

Aldehyde dehydrogenases catalyze the oxidation of aliphatic and aromatic aldehydes. The enzymes are present in most life forms. Representative enzymes include: (i) succinate-semialdehyde dehydrogenase, a NADP⁺-dependent enzyme in E. coli that reduces succinate semialdehyde to succinate, (ii) betaine-aldehyde dehydrogenase, an enzyme present in plants and bacteria that is involved in the biosythesis of betaine, a quaternary ammonium compound accumulated in response to dry conditions, (iii) delta- l-pyrroline-5-carboxylate dehydrogenase, an enzyme present in yeast that converts proline to glutamate, (iv) methylmalonate-semialdehyde dehydrogenase, an enzyme present in numerous species, from bacteria to mammals, that is involved in valine catabolism, and (v) formyltetrahydrofolate dehydrogenase, a cytosolic enzyme in mammals responsible for the NADP⁺- dependent decarboxylative reduction of 10-formyltetrahydrofolate to tetrahydrofolate and CO₂ as well as the NADP⁺-independent hydrolysis of 10-foraιyltetι-ahydrofolate to tetrahydrofolate and formate. The amino-terminal domain of rat liver 10-Formyltetrahydrofolate dehydrogenase (residues 1-203) is 24-30% identical to a group of glycinamide ribonucleotide fiansformylases (EC 2.1.2.1). The active site of these enzymes comprises a glutamic acid and a cysteine residue that are conserved in all enzymes of the family (Weretilnyk, E.A. and A.D. Hanson (1990) Proc. Natl. Acad. Sci. USA 87:2745-2749; Cook, R.J. et al. (1991) J. Biol. Chem. 266:4965-4973; Steele, M.I. et al. (1992) J. Biol. Chem. 267:13585-13592; and Krapenko, S.A. et al. (1995) 270:519-522).

Defects in members of the aldehyde dehydrogenase gene family have been linked directly to human diseases. For example, a defect in aldehyde dehydrogenase 10 (fatty aldehyde dehydrogenase) results in the autosomal recessive neurocutaneous disorder, Sjoegren-Larsson syndrome (SLS). This disease is characterized by severe mental retardation, spastic di or tetra-plegia and congenital ichthyosis (increased keratinization) which is usually evident at birth. Afflicted individuals may also present with white spots on the retina, seizures, short stature and speech defects (De Laurenzi, V. et al. (1996) Nat. Genet. 12:52-57). A defect in aldehyde dehydrogenase 4 (glutamate gamma-semialdehyde dehydrogenase; pyrroline-5-carboxylate dehydrogenase) results in hyperprolinemia, type TJ, an autosomal recessive disorder characterized by accumulation of plasma proline (10-15-fold excess). The clinical phenotype of this disorder varies from asymptomatic to neurological manifestations, including seizures and mental retardation (Hu, CA. et al. (1996) J. Biol. Chem. 271:9795-9800).

In addition, the mitochondrial enzyme aldehyde dehydrogenase 2 catalyzes the second step in ethanol utilization:

Step 1 : ethanol + NAD⁺ → acetaldehyde + NADH (alcohol dehydrogenase)

Step 2: acetaldehyde + NAD⁺ → acetic acid + NADH (aldehyde dehydrogenase)

Defects in aldehyde dehydrogenase result in acute alcohol intoxication. This genetic defect is very common in South-east Asians and South American Indians, while less common in Caucasians. The inactive variant allele encodes a single amino acid exchange (Hsu, L.C. et al. (1988) Genomics 2:57-65). Alcohol dehydrogenases Alcohol dehydrogenases (ADHs) oxidize simple alcohols to the corresponding aldehydes.

ADH is a cytosolic enzyme, prefers the cofactor NAD⁺, and also binds zinc ion. Liver contains the highest levels of ADH, with lower levels in kidney, lung, and the gastric mucosa.

Known ADH isoforms are dimeric proteins composed of 40 kDa subunits. There are five known gene loci which encode these subunits (a, b, g, p, c), and some of the loci have characterized allelic variants (b_l5 b₂, b₃, g_lt g_j). The subunits can form homodimers and heterodimers; the subunit composition determines the specific properties of the active enzyme. The holoenzymes have therefore been categorized as Class I (subunit compositions aa, ab, ag, bg, gg), Class U (pp), and Class m (cc). Class I ADH isozymes oxidize ethanol and other small aliphatic alcohols, and are inhibited by pyrazole. Class π isozymes prefer longer chain aliphatic and aromatic alcohols, are unable to oxidize methanol, and are not inhibited by pyrazole. Class UJ isozymes prefer even longer chain aliphatic alcohols (five carbons and longer) and aromatic alcohols, and are not inhibited by pyrazole. Peroxisomal β-oxidation enzymes Another example of the importance of redox reactions in cell metabolism is the degradation of saturated and unsaturated fatty acids by mitochondrial and peroxisomal beta-oxidation enzymes which sequentially remove two-carbon units from Coenzyme A (CoA)-activated fatty acids. The main beta- oxidation pathway degrades both saturated and unsaturated fatty acids while the auxiliary pathway performs additional steps required for the degradation of unsaturated fatty acids. The pathways of mitchondrial and peroxisomal beta-oxidation use similar enzymes, but have different substrate specificities and functions. Mitochondria oxidize short-, medium-, and long-chain fatty acids to produce energy for cells. Mitochondrial beta-oxidation is a major energy source for cardiac and skeletal muscle. In liver, it provides ketone bodies to the peripheral circulation when glucose levels are low as in starvation, endurance exercise, and diabetes (Eaton, S. et al. (1996) Biochem. J. 320:345-357). Peroxisomes oxidize medium-, long-, and very-long-chain fatty acids, dicarboxylic fatty acids, branched fatty acids, prostaglandins, xenobiotics, and bile acid intermediates. The chief roles of peroxisomal beta-oxidation are to shorten toxic lipophilic carboxylic acids to facilitate their excretion and to shorten very-long-chain fatty acids prior to mitochondrial beta-oxidation (Mannaerts, G.P. and P.P. Van Neldhoven (1993) Biochimie 75:147-158). The auxiliary beta-oxidation enzyme 2,4-dienoyl-CoA reductase catalyzes the following reaction:

trans-2, cis/trans-4-dienoyl-CoA + ΝADPH + H⁺— > trans-3-enoyl-CoA + ΝADP⁺

This reaction removes even-numbered double bonds from unsaturated fatty acids prior to their entry into the main beta-oxidation pathway (Koivuranta, K.T. et al. (1994) Biochem. J. 304:787-792). The enzyme may also remove odd-numbered double bonds from unsaturated fatty acids (Smeland, T.E. et al. (1992) Proc. Natl. Acad. Sci. USA 89:6673-6677). Rat 2,4-dienoyl-CoA reductase is located in both mitochondria and peroxisomes (Dommes, V. et al. (1981) J. Biol. Chem. 256:8259-8262). Two immunologically different forms of rat mitochondrial enzyme exist with molecular masses of 60 kDa and 120 kDa (Hakkola, E.H. and J.K. Hiltunen (1993) Eur. J. Biochem. 215:199-204). The 120 kDa mitochondrial rat enzyme is synthesized as a 335 amino acid precursor with a 29 amino acid N-terminal leader peptide which is cleaved to form the mature enzyme (Hirose, A. et al. (1990) Biochim. Biophys. Acta 1049:346-349). A human mitochondrial enzyme 83% similar to rat enzyme is synthesized as a 335 amino acid residue precursor with a 19 amino acid N-terminal leader peptide (Koivuranta, supra). These cloned human and rat mitochondrial enzymes function as homotetramers (Koivuranta, supra). A Saccharomyces cerevisiae peroxisomal 2,4-dienoyl-CoA reductase is 295 amino acids long, contains a C-terminal peroxisomal targeting signal, and functions as ahomodimer (Coe, J.G.S. et al. (1994) Mol. Gen. Genet. 244:661- 672; and Gurvitz, A. et al. (1997) J. Biol. Chem. 272:22140-22147). AU 2,4-dienoyl-CoA reductases have a fairly well conserved NADPH binding site motif of sequence (Koivuranta, supra).

The main pathway beta-oxidation enzyme enoyl-CoA hydratase catalyzes the following reaction:

2-trans-enoyl-CoA + H₂O < — > 3-hydroxyacyl-CoA

This reaction hydrates the double bond between C-2 and C-3 of 2-trans-enoyl-CoA, which is generated from saturated and unsaturated fatty acids (Engel, C.K. et al. (1996) EMBO J. 15:5135- 5145). This step is downstream from the step catalyzed by 2,4-dienoyl-reductase. Different enoyl- CoA hydratases act on short-, medium-, and long-chain fatty acids (Eaton, supra). Mitochondrial and peroxisomal enoyl-CoA hydratases occur as both mono-functional enzymes and as part of multifunctional enzyme complexes. Human liver mitochondrial short-chain enoyl-CoA hydratase is synthesized as a 290 amino acid precursor with a 29 amino acid N-terminal leader peptide (Kanazawa, M. et al. (1993) Enzyme Protein 47:9-13; and Janssen, U. et al. (1997) Genomics 40:470-475). Rat short-chain enoyl-CoA hydratase is 87% identical to the human sequence in the mature region of the protein and functions as a homohexamer (Kanazawa, supra; and Engel, supra). A mitochondrial trifunctional protein exists that has long-chain enoyl-CoA hydratase, 3-hydroxyacyl-CoA dehydrogenase, and long-chain 3-oxothiolase activities (Eaton, supra). In human peroxisomes, enoyl- CoA hydratase activity is found in both a 327 amino acid residue mono-functional enzyme and as part of a multi-functional enzyme, also known as bifunctional enzyme, which possesses enoyl-CoA hydratase, enoyl-CoA isomerase, and 3-hydroxyacyl-CoA hydrogenase activities (FitzPatrick, D.R. et al. (1995) Genomics 27:457-466; and Hoefler, G. et al. (1994) Genomics 19:60-67). A 339 amino acid residue human protein with short-chain enoyl-CoA hydratase activity also acts as an AU-specific RNA binding protein (Nakagawa, J. et al. (1995) Proc. Natl. Acad. Sci. USA 92:2051-2055). All enoyl-CoA hydratases share homology near two active site glutamic acid residues, with 17 amino acid residues highly conserved (Wu, W.-J. et al. (1997) Biochemistry 36:2211-2220).

Inherited deficiencies in mitochondrial and peroxisomal beta-oxidation enzymes are associated with severe diseases, some of which manifest themselves soon after birth and lead to death within a few years. Mitochondrial beta-oxidation associated deficiencies include, e.g., carnitine palmitoyl transferase and carnitine deficiency, very-long-chain acyl-CoA dehydrogenase deficiency, medium- chain acyl-CoA dehydrogenase deficiency, short-chain acyl-CoA dehydrogenase deficiency, electron transport flavoprotein and electron transport flavoprotein:ubiquinone oxidoreductase deficiency, trifunctional protein deficiency, and short-chain 3-hydroxyacyl-CoA dehydrogenase deficiency (Eaton, supra). Mitochondrial trifunctional protein (including enoyl-CoA hydratase) deficient patients have reduced long-chain enoyl-CoA hydratase activities and suffer from non-ketotic hypoglycemia, sudden infant death syndrome, cardiomyopathy, hepatic dysfunction, and muscle weakness, and may die at an early age (Eaton, supra). A patient with a deficiency in mitochondrial 2,4-dienoyl-CoA reductase was hypotonic soon after birth, had feeding difficulties, and died at four months from respiratory acidosis (Roe, C.R. et al. (1990) J. Clin. Invest. 85:1703-1707).

Defects in mitochondrial beta-oxidation are associated with Reye's syndrome, a disease characterized by hepatic dysfunction and encephalopathy that sometimes follows viral infection in children. Reye's syndrome patients may have elevated serum levels of free fatty acids (Cotran, R.S. et al. (1994) Robbins Pathologic Basis of Disease, W.B. Saunders Co., Philadelphia PA, p.866). Patients with mitochondrial short-chain 3-hydroxyacyl-CoA dehydrogenase deficiency and medium- chain 3-hydroxyacyl-CoA dehydrogenase deficiency also exhibit Reye-like illnesses (Eaton, supra; and Egidio, R.J. et al. (1989) Am. Fam. Physician 39:221-226).

Inherited conditions associated with peroxisomal beta-oxidation include Zellweger syndrome, neonatal adrenoleukodystrophy, infantile Refsum's disease, acyl-CoA oxidase deficiency, peroxisomal thiolase deficiency, and bifunctional protein deficiency (Suzuki, Y. et al. (1994) Am. J. Hum. Genet. 54:36-43; Hoefler, supra). Patients with peroxisomal bifunctional enzyme deficiency, including that of enoyl-CoA hydratase, suffer from hypotonia, seizures, psychomotor defects, and defective neuronal migration; accumulate very-long-chain fatty acids; and typically die within a few years of birth (Watkins, P.A. et al. (1989) J. Clin. Invest. 83:771-777).

Peroxisomal beta-oxidation is impaired in cancerous tissue. Although neoplastic human breast epithelial cells have the same number of peroxisomes as do normal cells, fatty acyl-CoA oxidase activity is lower than in control tissue (el Bouhtoury, F. et al. (1992) J. Pathol. 166:27-35). Human colon carcinomas have fewer peroxisomes than normal colon tissue and have lower fatty-acyl-CoA oxidase and bifunctional enzyme (including enoyl-CoA hydratase) activities than normal tissue (Cable, S. et al. (1992) Virchows Arch. B Cell Pathol. Incl. Mol. Pathol. 62:221-226). Acyl-CoA dehydrogenases

The acyl-CoA dehydrogenase family comprises at least seven members of which four are involved in beta-oxidation of fatty acids (see above). Very long chain fatty acids, dicarboxylic fatty acids, some prostanoids, pristanic acid, bile acid intermediates, and xenobiotic compounds are degraded by beta-oxidation in mammalian peroxisomes (Van Veldhoven, P.P. et al. (1999) Adv. Exp. Med. Biol. 466:261-272). For example, very long chain acyl-CoA dehydrogenase (VLCAD), a homodimer of a 70-kDa mitochondrial membrane-associated protein (Souri, M. et al. (1998) FEBS Lett. 426:187-190), catalyzes the initial flavin-dependent oxidation of acyl-CoA fatty acids in the mitochondria. In the process, electrons are transferred to an electron-transferring flavoprotein. Patients with VLCAD deficiency present with early onset cardiomyopathy that results in a high incidence of hypoketotic hypoglycemia and infant death. These conditions may result from the failure to express VLCAD or the expression of mutated forms of VLCAD. In at least one case, a nucleotide change in the gene for VLCAD resulted in the incorrect splicing of the mRNA and the synthesis of a defective protein (Watanabe, H. et al. (2000) Hum. Mutat. 15:430-438). Mutations in exons 10 and 12 that result in amino acid substitutions or nonsense mutations have also been reported (He, G. et al. (1999) Biochem. Biophys. Res. Commun. 264:483-487). A lethal genetic illness has also been associated with a single amino acid substitution in a medium-chain acyl-CoA dehydrogenase (Yang, B.Z. (2000) Mol. Genet. Metab. 69:259-262).

The remaining three enzymes of the acyl-CoA dehydrogenase family are involved in the catabolism of amino acids (i.e., isovaleryl-CoA dehydrogenase, short/branched chain acyl-CoA dehydrogenase, and glutaryl-CoA dehydrogenase). Isovaleryl-CoA dehydrogenase (IVD), for example, catalyzes the conversion of isovaleryl-CoA to methylcrotonyl-CoA in the leucine catabolic pathway. IVD is a homotetramer of 175 kDa that contains one FAD prosthetic group per subunit. The subunits are synthesized with a 2 kDa N-terminal leader sequence that is proteolytically processed to yield the mature polypeptide. The gene encoding IVD maps to human chromosome 15 and spans 15 kilobases, consisting of 12 exons and 11 introns. Five different classes of mutations have been identified in cell lines from patients with isovaleric acidemia, a disease caused by a deficiency of IVD (Volchenboum, S.L. and J. Vockley (2000) J. Biol. Chem. 275:7958-7963 and Reinard, T. et al. (2000) J. Biol. Chem. 275:33738-33743). 6-ρhosphogluconate dehydrogenase

6-phosρhogluconate dehydrogenase (6-PGDH) catalyses the NADP⁺-dependent oxidative decarboxylation of 6-phosphogluconate to ribulose 5-phosphate with the production of NADPH. The absence or inhibition of 6-PGDH results in the accumulation of 6-phosphogluconate to toxic levels in eukaryotic cells. 6-PGDH is the third enzyme of the pentose phosphate pathway (PPP) and is ubiquitous in nature. In some heterofermentatative species, NAD+ is used as a cofactor with the subsequent production of NADH.

The reaction proceeds through a 3-keto intermediate which is decarboxylated to give the enol of ribulose 5-phosphate, then converted to the keto product following tautomerization of the enol (Berdis A.J. and P.F. Cook (1993) Biochemistry 32:2041-2046). 6-PGDH activity is regulated by the inhibitory effect of NADPH, and the activating effect of 6-phosphogluconate (Rippa, M. et al. (1998) Biochim. Biophys. Acta 1429:83-92). Deficiencies in 6-PGDH activity have been linked to chronic hernolytic anemia. The targeting of specific forms of 6-PGDH (e.g., enzymes found in trypanosomes) has been suggested as a means for controlling parasitic infections (Tetaud, E. et al. (1999) Biochem. J. 338:55- 60). For example, the T. bracei enzyme is markedly more sensitive to inhibition by the substrate analogue 6-phospho-2-deoxygluconate and the coenzyme analogue adenosine 2',5'-bisphosphate, compared to the mammalian enzyme (Hanau, S. et al. (1996) Eur. J. Biochem. 240:592-599). Ribonucleotide diphosphate reductase

Ribonucleotide diphosphate reductase catalyzes the reduction of ribonucleotide diphosphates . (i.e., ADP, GDP, CDP, and UDP) to their corresponding deoxyribonucleotide diphosphates (i.e., dADP, dGDP, dCDP, and dUDP) which are used for the synthesis of DNA. Ribonucleotide diphosphate reductase thereby performs a crucial role in the de novo synthesis of deoxynucleotide precursors. Deoxynucleotides are also produced from deoxynucleosides by nucleoside kinases via the salvage pathway.

Mammalian ribonucleotide diphosphate reductase comprises two components, an effector- binding component (E) and a non-heme iron component (F). Component E binds the nucleoside triphosphate effectors while component F contains the iron radical necessary for catalysis. Molecular weight determinations of the E and F components, as well as the holoenzyme, vary according to the methods used in purification of the proteins and the particular laboratory. Component E is approximately 90-100 kDa, component F is approximately 100-120 kDa, and the holoenzyme is 200- 250 kDa. Ribonucleotide diphosphate reductase activity is adversely effected by iron chelators, such as thiosemicarbazones, as well as EDTA. Deoxyribonucleotide diphosphates also appear to be negative allosteric effectors of ribonucleotide diphosphate reductase. Nucleotide triphosphates (both ribo- and deoxyribo-) appear to stimulate the activity of the enzyme. 3-methyl-4-nitrophenol, a metabolite of widely used organophosphate pesticides, is a potent inhibitor of ribonucleotide diphosphate reductase in mammalian cells. Some evidence suggests that ribonucleotide diphosphate reductase activity in DNA virus (e.g., herpes virus) -infected cells and in cancer cells is less sensitive to regulation by allosteric regulators and a correlation exists between high ribonucleotide diphosphate reductase activity levels and high rates of cell proliferation (e.g., in hepatomas). This observation suggests that virus-encoded ribonucleotide diphosphate reductases, and those present in cancer cells, are capable of maintaining an increased supply deoxyribonucleotide pool for the production of virus genomes or for the increased DNA synthesis which characterizes cancers cells. Ribonucleotide diphosphate reductase is thus a target for therapeutic intervention (Nutter, L.M. and Y.-C. Cheng (1984) Pharmac. Ther. 26:191-207; and Wright, J.A. (1983) Pharmac. Ther. 22:81-102). Dihydrodiol dehydrogenase

Dihydrodiol dehydrogenases (DD) are monomeric, NAD(P)⁺-dependent, 34-37 kDa enzymes responsible for the detoxification trans-dihydrodiol and <røt/-diol epoxide metabolites of polycyclic aromatic hydrocarbons (PAH) such as benzo[α]yrene, benz[α] anthracene, 7-methyl- benzfαjanthracene, 7,12-dimethyl-benz[α]anthracene, chrysene, and 5-methyl-chrysene. In mammalian cells, an environmental PAH toxin such as benzo[α]yrene is initially epoxidated by a microsomal cytochrome P450 to yield 7i?,8R-arene-oxide and subsequently (-)-7i?,8R-dihydrodiol ((-)- trαns-7,8-dihydroxy-7,8-dihydroberιzo[α]pyrene or (-)-tra»,s-B[ ]P-dioι). This latter compound is further transformed to the anti-diol epoxide of benzo[α]pyrene (i.e., (±)-anti-7 ?,8α-dihydroxy-9α,10α- epoxy-7,8,9,10-tetrahydrobenzo[ ]pyrene), by the same enzyme of a different enzyme, depending on the species. This resulting anti-diol epoxide of benzo[α]yrene, or the corresponding derivative from another PAH compound, is highly mutagenic.

DD efficiently oxidizes the precursor of the αnft'-diol epoxide (i.e., trans-dihydrodioi) to transient catechols which auto-oxidize to quinones, also producing hydrogen peroxide and semiquinone radicals. This reaction prevents the formation of the highly carcinogenic anti-diol. Antt-diols are not themselves substrates for DD yet the addition of DD to a sample comprising an αwti-diol compound results in a significant decrease in the induced mutation rate observed in the Ames test. In this instance, DD is able to bind to and sequester the anti-diol, even though it is not oxidized. Whether through oxidation or sequestration, DD plays an important role in the detoxification of metabolites of xenobiotic polycyclic compounds (Penning, T.M. (1993) Chemico-Biological Interactions 89:1-34). 15-oxoprostaglandin 13-reductase

15-oxoprostaglandin 13-reductase (PGR) and 15-hydroxyprostaglandin dehydrogenase (15- PGDH) are enzymes present in the lung that are responsible for degrading circulating prostaglandins. Oxidative catabolism via passage through the pulmonary system is a common means of reducing the concentration of circulating prostaglandins. 15-PGDH oxidizes the 15-hydroxyl group of a variety of prostaglandins to produce the corresponding 15-oxo compounds. The 15-oxo derivatives usually have reduced biological activity compared to the 15-hydroxyl molecule. PGR further reduces the 13,14 double bond of the 15-oxo compound which typically leads to a further decrease in biological activity. PGR is a monomer with a molecular weight of approximately 36 kDa. The enzyme requires NADH or NADPH as a cofactor with a preference for NADH. The 15-oxo derivatives of prostaglandins PGE_l5 PGE₂, and PGE_2α are all substrates for PGR; however, the non-derivatized prostaglandins (i.e., PGEj, PGE₂, and PGE_2α) are not substrates (Ensor, CM. et al. (1998) Biochem. J. 330:103-108). 15-PGDH and PGR also catalyze the metabolism of lipoxin A₄ (LXA₄). Lipoxins (LX) are autacoids, lipids produced at the sites of localized inflammation, which down-regulate polymorphonuclear leukocyte (PMN) function and promote resolution of localized trauma. Lipoxin production is stimulated by the administration of aspirin in that cells displaying cyclooxygenase II (COX JJ) that has been acetylated by aspirin and cells that possess 5-lipoxygenase (5-LO) interact and produce lipoxin. 15-PGDH generates 15-oxo-LXA₄ with PGR further converting the 15-oxo compound to 13,14-dihydro-15-oxo-LXA₄ (Clish, C.B. et al. (2000) J. Biol. Chem. 275:25372-25380). This finding suggests a broad substrate specificity of the prostaglandin dehydrogenases and has implications for these enzymes in drag metabolism and as targets for therapeutic intervention to regulate inflammation. GMC oxidoreductases The GMC (glucose-methanol-choline) oxidoreductase family of enzymes was defined based on sequence alignments of Drosophila melanogaster glucose dehydrogenase, Escherichia coli choline dehydrogenase, Aspergillus niger glucose oxidase, and Hansenula polymorpha methanol oxidase. Despite their different sources and substrate specificities, these four flavoproteins are homologous, being characterized by the presence of several distinctive sequence and structural features. Each molecule contains a canonical ADP-binding, beta-alpha-beta mononucleotide-binding motif close to the amino terminus. This fold comprises a four-stranded parallel beta-sheet sandwiched between a three- stranded antiparallel beta-sheet and alpha-helices. Nucleotides bind in similar positions relative to this chain fold (Cavener, D.R. (1992) J. Mol. Biol. 223:811-814; and Wierenga, R.K. et al. (1986) J. Mol. Biol. 187:101-107). Members of the GMC oxidoreductase family also share a consensus sequence near the central region of the polypeptide. Additional members of the GMC oxidoreductase family include cholesterol oxidases from Brevibacterium sterolicum and Streptomyces; and an alcohol dehydrogenase from Pseudomonas oleovorans (Cavener, D.R., supra; Henikoff, S. and J.G. Henikoff (1994) Genomics 19:97-107; van Beilen, J.B. et al. (1992) Mol. Microbiol. 6:3121-3136). IMP dehvdrogenase/GMP reductase

IMP dehydrogenase and GMP reductase are two oxidoreductases which share many regions of sequence similarity. IMP dehydrogenase (EC 1.1.1.205) catalyes the NAD-dependent reduction of EVIP (inosine monophosphate) into XMP (xanthine monophosphate) as part of de novo GTP biosynthesis (Collart, F.R. and E. Huberman (1988) J. Biol. Chem. 263:15769-15772). GMP reductase catalyzes the NADPH-dependent reductive deamination of GMP into IMP, helping to maintain the intracellular balance of adenine and guanine nucleotides (Andrews, S.C. and J.R. Guest (1988) Biochem. J. 255:35-43). Pyridine nucleotide-disulphide oxidoreductases Pyridine nucleotide-disulphide oxidoreductases are FAD flavoproteins involved in the transfer of reducing equivalents from FAD to a substrate. These flavoproteins contain a pair of redox-active cysteines contained within a consensus sequence which is characteristic of this protein family (Kurlyan, J. et al. (1991) Nature 352:172-174). Members of this family of oxidoreductases include glutathione reductase (EC 1.6.4.2); thioredoxin reductase of higher eukaryotes (EC 1.6.4.5); trypanothione reductase (EC 1.6.4.8) ; lipoamide dehydrogenase (EC 1.8.1.4), the E3 component of alpha-ketoacid dehydrogenase complexes; and mercuric reductase (EC 1.16.1.1). Enzymes involved in tyrosine catalysis

The degradation of the amino acid tyrosine to either succinate and pyruvate or fumarate and acetoacetate, requires a large number of enzymes and generates a large number of intermediate compounds. In addition, many xenobiotic compounds may be metabolized using one or more reactions that are part of the tyrosine catabolic pathway. While the pathway has been studied primarily in bacteria, tyrosine degradation is known to occur in a variety of organisms and is likely to involve many of the same biological reactions. The enzymes involved in the degradation of tyrosine to fumarate and acetoacetate (e.g., in Pseudomonas species) include the oxidoreductases 4-hydroxvphenylpyruvate dioxygenase, and homogentisate 1,2-dioxygenase.

In humans, acquired or inherited genetic defects in enzymes of the tyrosine degradation pathway may result in hereditary tyrosinemia. One form of this disease, hereditary tyrosinemia 1 (HT1) is caused by a deficiency in the enzyme fumarylacetoacetate hydrolase, the last enzyme in the pathway in organisms that metabolize tyrosine to fumarate and acetoacetate. HT1 is characterized by progressive liver damage beginning at infancy, and increased risk for liver cancer (Endo, F. et al. (1997) J. Biol. Chem. 272:24426-24432).

The discoveiy of new oxidoreductases, and the polynucleotides encoding them, satisfies a need in the art by providing new compositions which are useful in the diagnosis, prevention, and treatment of cell proliferative, neurological, metabolic, and smooth muscle disorders, and in the assessment of the effects of exogenous compounds on the expression of nucleic acid and amino acid sequences of oxidoreductases.

SUMMARY OF THE INVENTION

The invention features purified polypeptides, oxidoreductases, referred to collectively as "OXRD" and individually as "OXRD-1," "OXRD-2," and "OXRD-3." In one aspect, the invention provides an isolated polypeptide selected from the group consisting of a) a polypeptide comprising an amino acid sequence selected from the group consisting of SEQ ID NO: 1-3, b) a polypeptide comprising a naturally occurring amino acid sequence at least 90% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 1-3, c) a biologically active fragment of a polypeptide having an amino acid sequence selected from the group consisting of SEQ ID NO: 1-3, and d) an immunogenic fragment of a polypeptide having an amino acid sequence selected from the group consisting of SEQ ID NO: 1-3. In one alternative, the invention provides an isolated polypeptide comprising the amino acid sequence of SEQ ED NO : 1 -3.

The invention further provides an isolated polynucleotide encoding a polypeptide selected from the group consisting of a) a polypeptide comprising an amino acid sequence selected from the group consisting of SEQ ID NO: 1-3, b) a polypeptide comprising a naturally occurring amino acid sequence at least 90% identical to an amino acid sequence selected from the group consisting of SEQ JD NO: 1-3, c) a biologically active fragment of a polypeptide having an amino acid sequence selected from the group consisting of SEQ JD NO:l-3, and d) an immunogenic fragment of a polypeptide having an amino acid sequence selected from the group consisting of SEQ ID NO: 1-3. In one alternative, the polynucleotide encodes a polypeptide selected from the group consisting of SEQ JD NO: 1-3. In another alternative, the polynucleotide is selected from the group consisting of SEQ ID NO:4-6.

Additionally, the invention provides a recombinant polynucleotide comprising a promoter sequence operably linked to a polynucleotide encoding a polypeptide selected from the group consisting of a) a polypeptide comprising an amino acid sequence selected from the group consisting of SEQ ID NO:l-3, b) a polypeptide comprising a naturally occurring amino acid sequence at least 90% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 1-3, c) a biologically active fragment of a polypeptide having an amino acid sequence selected from the group consisting of SEQ ED NO:l-3, and d) an immunogenic fragment of a polypeptide having an amino acid sequence selected from the group consisting of SEQ ID NO: 1-3. In one alternative, the invention provides a cell transformed with the recombinant polynucleotide. In another alternative, the invention provides a transgenic organism comprising the recombinant polynucleotide.

The invention also provides a method for producing a polypeptide selected from the group consisting of a) a polypeptide comprising an amino acid sequence selected from the group consisting of SEQ ID NO: 1-3, b) a polypeptide comprising a naturally occurring amino acid sequence at least 90% identical to an amino acid sequence selected from the group consisting of SEQ ED NO:l -3, c) a biologically active fragment of a polypeptide having an amino acid sequence selected from the group consisting of SEQ ED NO: 1-3, and d) an immunogenic fragment of a polypeptide having an amino acid sequence selected from the group consisting of SEQ ED NO: 1-3. The method comprises a) culturing a cell under conditions suitable for expression of the polypeptide, wherein said cell is transformed with a recombinant polynucleotide comprising a promoter sequence operably linked to a polynucleotide encoding the polypeptide, and b) recovering the polypeptide so expressed.

Additionally, the invention provides an isolated antibody which specifically binds to a polypeptide selected from the group consisting of a) a polypeptide comprising an amino acid sequence selected from the group consisting of SEQ ED NO: 1-3, b) a polypeptide comprising a naturally occurring amino acid sequence at least 90% identical to an amino acid sequence selected from the group consisting of SEQ ED NO: 1-3, c) a biologically active fragment of a polypeptide having an amino acid sequence selected from the group consisting of SEQ ID NO: 1-3, and d) an immunogenic fragment of a polypeptide having an amino acid sequence selected from the group consisting of SEQ ED NO:l-3.

The invention further provides an isolated polynucleotide selected from the group consisting of a) a polynucleotide comprising a polynucleotide sequence selected from the group consisting of SEQ ED NO:4-6, b) a polynucleotide comprising a naturally occurring polynucleotide sequence at least 90% identical to a polynucleotide sequence selected from the group consisting of SEQ ED NO:4- 6, c) a polynucleotide complementary to the polynucleotide of a), d) a polynucleotide complementary to the polynucleotide of b), and e) an RNA equivalent of a)-d). En one alternative, the polynucleotide comprises at least 60 contiguous nucleotides.

Additionally, the invention provides a method for detecting a target polynucleotide in a sample, said target polynucleotide having a sequence of a polynucleotide selected from the group consisting of a) a polynucleotide comprising a polynucleotide sequence selected from the group consisting of SEQ ED NO:4-6, b) a polynucleotide comprising a naturally occurring polynucleotide sequence at least 90% identical to a polynucleotide sequence selected from the group consisting of SEQ JD NO:4-6, c) a polynucleotide complementary to the polynucleotide of a), d) a polynucleotide complementary to the polynucleotide of b), and e) an RNA equivalent of a)-d). The method comprises a) hybridizing the sample with a probe comprising at least 20 contiguous nucleotides comprising a sequence complementary to said target polynucleotide in the sample, and which probe specifically hybridizes to said target polynucleotide, under conditions whereby a hybridization complex is formed between said probe and said target polynucleotide or fragments thereof, and b) detecting the presence or absence of said hybridization complex, and optionally, if present, the amount thereof. In one alternative, the probe comprises at least 60 contiguous nucleotides.

The invention further provides a method for detecting a target polynucleotide in a sample, said target polynucleotide having a sequence of a polynucleotide selected from the group consisting of a) a polynucleotide comprising a polynucleotide sequence selected from the group consisting of SEQ ID NO:4-6, b) a polynucleotide comprising a naturally occurring polynucleotide sequence at least 90% identical to a polynucleotide sequence selected from the group consisting of SEQ ID NO:4-6, c) a polynucleotide complementary to the polynucleotide of a), d) a polynucleotide complementary to the polynucleotide of b), and e) an RNA equivalent of a)-d). The method comprises a) amplifying said target polynucleotide or fragment thereof using polymerase chain reaction amplification, and b) detecting the presence or absence of said amplified target polynucleotide or fragment thereof, and, optionally, if present, the amount thereof.

The invention further provides a composition comprising an effective amount of a polypeptide selected from the group consisting of a) a polypeptide comprising an amino acid sequence selected from the group consisting of SEQ ED NO: 1-3, b) a polypeptide comprising a naturally occurring amino acid sequence at least 90% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 1-3, c) a biologically active fragment of a polypeptide having an amino acid sequence selected from the group consisting of SEQ ED NO: 1-3, and d) an immunogenic fragment of a polypeptide having an amino acid sequence selected from the group consisting of SEQ ED NO:l-3, and a pharmaceutically acceptable excipient. Eh one embodiment, the composition comprises an amino acid sequence selected from the group consisting of SEQ JD NO: 1-3. The invention additionally provides a method of treating a disease or condition associated with decreased expression of functional OXRD, comprising administering to a patient in need of such treatment the composition. The invention also provides a method for screening a compound for effectiveness as an agonist of a polypeptide selected from the group consisting of a) a polypeptide comprising an amino acid sequence selected from the group consisting of SEQ ID NO: -3, b) a polypeptide comprising a naturally occurring amino acid sequence at least 90% identical to an amino acid sequence selected from the group consisting of SEQ ED NO: 1-3, c) a biologically active fragment of a polypeptide having an amino acid sequence selected from the group consisting of SEQ ED NO: 1-3, and d) an immunogenic fragment of a polypeptide having an amino acid sequence selected from the group consisting of SEQ JD NO: 1-3. The method comprises a) exposing a sample comprising the polypeptide to a compound, and b) detecting agonist activity in the sample. In one alternative, the invention provides a composition comprising an agonist compound identified by the method and a pharmaceutically acceptable excipient. In another alternative, the invention provides a method of treating a disease or condition associated with decreased expression of functional OXRD, comprising administering to a patient in need of such treatment the composition.

Additionally, the invention provides a method for screening a compound for effectiveness as an antagonist of a polypeptide selected from the group consisting of a) a polypeptide comprising an amino acid sequence selected from the group consisting of SEQ ED NO: 1-3, b) a polypeptide comprising a naturally occurring amino acid sequence at least 90% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 1-3, c) a biologically active fragment of a polypeptide having an amino acid sequence selected from the group consisting of SEQ JD NO:l-3, and d) an immunogenic fragment of a polypeptide having an amino acid sequence selected from the group consisting of SEQ ED NO:l-3. The method comprises a) exposing a sample comprising the polypeptide to a compound, and b) detecting antagonist activity in the sample. In one alternative, the invention provides a composition comprising an antagonist compound identified by the method and a pharmaceutically acceptable excipient. En another alternative, the invention provides a method of treating a disease or condition associated with overexpression of functional OXRD, comprising administering to a patient in need of such treatment the composition.

The invention further provides a method of screening for a compound that specifically binds to a polypeptide selected from the group consisting of a) a polypeptide comprising an amino acid sequence selected from the group consisting of SEQ JD NO:l-3, b) a polypeptide comprising a naturally occurring amino acid sequence at least 90% identical to an amino acid sequence selected from the group consisting of SEQ JD NO: 1-3, c) a biologically active fragment of a polypeptide having an amino acid sequence selected from the group consisting of SEQ JD NO: 1-3, and d) an immunogenic fragment of a polypeptide having an amino acid sequence selected from the group consisting of SEQ JD NO: 1-3. The method comprises a) combining the polypeptide with at least one test compound under suitable conditions, and b) detecting binding of the polypeptide to the test compound, thereby identifying a compound that specifically binds to the polypeptide.

The invention further provides a method of screening for a compound that modulates the activity of a polypeptide selected from the group consisting of a) a polypeptide comprising an arnino acid sequence selected from the group consisting of SEQ ID NO: 1-3, b) a polypeptide comprising a naturally occurring amino acid sequence at least 90% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 1-3, c) a biologically active fragment of a polypeptide having an amino acid sequence selected from the group consisting of SEQ ED NO: 1-3, and d) an immunogenic fragment of a polypeptide having an amino acid sequence selected from the group consisting of SEQ ED NO: 1-3. The method comprises a) combining the polypeptide with at least one test compound under conditions permissive for the activity of the polypeptide, b) assessing the activity of the polypeptide in the presence of the test compound, and c) comparing the activity of the polypeptide in the presence of the test compound with the activity of the polypeptide in the absence of the test compound, wherein a change in the activity of the polypeptide in the presence of the test compound is indicative of a compound that modulates the activity of the polypeptide.

The invention further provides a method for screening a compound for effectiveness in altering expression of a target polynucleotide, wherein said target polynucleotide comprises a polynucleotide sequence selected from the group consisting of SEQ ED NO:4-6, the method comprising a) exposing a sample comprising the target polynucleotide to a compound, b) detecting altered expression of the target polynucleotide, and c) comparing the expression of the target polynucleotide in the presence of varying amounts of the compound and in the absence of the compound.

The invention further provides a method for assessing toxicity of a test compound, said method comprising a) treating a biological sample containing nucleic acids with the test compound; b) hybridizing the nucleic acids of the treated biological sample with a probe comprising at least 20 contiguous nucleotides of a polynucleotide selected from the group consisting of i) a polynucleotide comprising a polynucleotide sequence selected from the group consisting of SEQ ID NO:4-6, ii) a polynucleotide comprising a naturally occurring polynucleotide sequence at least 90% identical to a polynucleotide sequence selected from the group consisting of SEQ JD NO:4-6, iii) a polynucleotide having a sequence complementary to i), iv) a polynucleotide complementary to the polynucleotide of ii), and v) an RNA equivalent of i)-iv). Hybridization occurs under conditions whereby a specific hybridization complex is formed between said probe and a target polynucleotide in the biological sample, said target polynucleotide selected from the group consisting of i) a polynucleotide comprising a polynucleotide sequence selected from the group consisting of SEQ JD NO:4-6, ii) a polynucleotide comprising a naturally occurring polynucleotide sequence at least 90% identical to a polynucleotide sequence selected from the group consisting of SEQ JD NO:4-6, iii) a polynucleotide complementary to the polynucleotide of i), iv) a polynucleotide complementary to the polynucleotide of ii), and v) an RNA equivalent of i)-iv). Alternatively, the target polynucleotide comprises a fragment of a polynucleotide sequence selected from the group consisting of i)-v) above; c) quantifying the amount of hybridization complex; and d) comparing the amount of hybridization complex in the treated biological sample with the amount of hybridization complex in an untreated biological sample, wherein a difference in the amount of hybridization complex in the treated biological sample is indicative of toxicity of the test compound.

BRIEF DESCRIPTION OF THE TABLES

Table 1 summarizes the nomenclature for the full length polynucleotide and polypeptide sequences of the present invention.

Table 2 shows the GenBank identification number and annotation of the nearest GenBank homolog for polypeptides of the invention. The probability scores for the matches between each polypeptide and its homolog(s) are also shown.

Table 3 shows structural features of polypeptide sequences of the invention, including predicted motifs and domains, along with the methods, algorithms, and searchable databases used for analysis of the polypeptides.

Table 4 lists the cDNA and/or genomic DNA fragments which were used to assemble polynucleotide sequences of the invention, along with selected fragments of the polynucleotide sequences. Table 5 shows the representative cDNA library for polynucleotides of the invention.

Table 6 provides an appendix which describes the tissues and vectors used for construction of the cDNA libraries shown in Table 5.

Table 7 shows the tools, programs, and algorithms used to analyze the polynucleotides and polypeptides of the invention, along with applicable descriptions, references, and threshold parameters.

DESCRIPTION OF THE INVENTION

Before the present proteins, nucleotide sequences, and methods are described, it is understood that this invention is not limited to the particular machines, materials and methods described, as these may vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to limit the scope of the present invention which will be limited only by the appended claims. It must be noted that as used herein and in the appended claims, the singular forms "a," "an," and "the" include plural reference unless the context clearly dictates otherwise. Thus, for example, a reference to "a host cell" includes a plurality of such host cells, and a reference to "an antibody" is a reference to one or more antibodies and equivalents thereof known to those skilled in the art, and so forth. Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any machines, materials, and methods similar or equivalent to those described herein can be used to practice or test the present invention, the preferred machines, materials and methods are now described. All publications mentioned herein are cited for the purpose of describing and disclosing the cell lines, protocols, reagents and vectors which are reported in the publications and which might be used in connection with the invention. Nothing herein is to be construed as an admission that the invention is not entitled to antedate such disclosure by virtue of prior invention. DEFINITIONS

"OXRD" refers to the amino acid sequences of substantially purified OXRD obtained from any species, particularly a mammalian species, including bovine, ovine, porcine, murine, equine, and human, and from any source, whether natural, synthetic, semi-synthetic, or recombinant.

The term "agonist" refers to a molecule which intensifies or mimics the biological activity of OXRD. Agonists may include proteins, nucleic acids, carbohydrates, small molecules, or any other compound or composition which modulates the activity of OXRD either by directly interacting with OXRD or by acting on components of the biological pathway in which OXRD participates.

An "allelic variant" is an alternative form of the gene encoding OXRD. Allelic variants may result from at least one mutation in the nucleic acid sequence and may result in altered mRNAs or in polypeptides whose structure or function may or may not be altered. A gene may have none, one, or many allelic variants of its naturally occurring form. Common mutational changes which give rise to allelic variants are generally ascribed to natural deletions, additions, or substitutions of nucleotides. Each of these types of changes may occur alone, or in combination with the others, one or more times in a given sequence.

"Altered" nucleic acid sequences encoding OXRD include those sequences with deletions, insertions, or substitutions of different nucleotides, resulting in a polypeptide the same as OXRD or a polypeptide with at least one functional characteristic of OXRD. Included within this definition are polymorphisms which may or may not be readily detectable using a particular oligonucleotide probe of the polynucleotide encoding OXRD, and improper or unexpected hybridization to allelic variants, with a locus other than the normal chromosomal locus for the polynucleotide sequence encoding OXRD. The encoded protein may also be "altered," and may contain deletions, insertions, or substitutions of amino acid residues which produce a silent change and result in a functionally equivalent OXRD. Deliberate amino acid substitutions may be made on the basis of similarity in polarity, charge, solubility, hydrophobicity, hydrophilicity, and/or the amphipathic nature of the residues, as long as the biological or immunological activity of OXRD is retained. For example, negatively charged amino acids may include aspartic acid and glutamic acid, and positively charged amino acids may include lysine and arginine. Amino acids with uncharged polar side chains having similar hydrophilicity values may include: asparagine and glutamine; and serine and threonine. Amino acids with uncharged side chains having similar hydrophilicity values may include: leucine, isoleucine, and valine; glycine and alanine; and phenylalanine and tyrosine.

The terms "amino acid" and "amino acid sequence" refer to an oligopeptide, peptide, polypeptide, or protein sequence, or a fragment of any of these, and to naturally occurring or synthetic molecules. Where "amino acid sequence" is recited to refer to a sequence of a naturally occurring protein molecule, "amino acid sequence" and like terms are not meant to limit the amino acid sequence to the complete native amino acid sequence associated with the recited protein molecule. "Amplification" relates to the production of additional copies of a nucleic acid sequence. Amplification is generally carried out using polymerase chain reaction (PCR) technologies well known in the art.

The term "antagonist" refers to a molecule which inhibits or attenuates the biological activity of OXRD. Antagonists may include proteins such as antibodies, nucleic acids, carbohydrates, small molecules, or any other compound or composition which modulates the activity of OXRD either by directly interacting with OXRD or by acting on components of the biological pathway in which OXRD participates.

The term "antibody" refers to intact immunoglobulin molecules as well as to fragments thereof, such as Fab, F(ab')₂, and Fv fragments, which are capable of binding an epitopic determinant. Antibodies that bind OXRD polypeptides can be prepared using intact polypeptides or using fragments containing small peptides of interest as the immunizing antigen. The polypeptide or oligopeptide used to immunize an animal (e.g., a mouse, a rat, or a rabbit) can be derived from the translation of RNA, or synthesized chemically, and can be conjugated to a carrier protein if desired. Commonly used carriers that are chemically coupled to peptides include bovine serum albumin, thyroglobulin, and keyhole limpet hemocyanin (KLH). The coupled peptide is then used to immunize the animal. The term "antigenic determinant" refers to that region of a molecule (i.e., an epitope) that makes contact with a particular antibody. When a protein or a fragment of a protein is used to immunize a host animal, numerous regions of the protein may induce the production of antibodies which bind specifically to antigenic determinants (particular regions or three-dimensional structures on the protein). An antigenic determinant may compete with the intact antigen (i.e., the immunogen used to elicit the immune response) for binding to an antibody.

The term "aptamer" refers to a nucleic acid or oligonucleotide molecule that binds to a specific molecular target. Aptamers are derived from an in vitro evolutionary process (e.g., SELEX (Systematic Evolution of Ligands by Exponential Enrichment), described in U.S. Patent No. 5,270,163), which selects for target-specific aptamer sequences from large combinatorial libraries. Aptamer compositions may be double-stranded or single-stranded, and may include deoxyribonucleotides, ribonucleotides, nucleotide derivatives, or other nucleotide-like molecules. The nucleotide components of an aptamer may have modified sugar groups (e.g., the 2'-OH group of a ribonucleotide may be replaced by 2 -F or 2'-NH₂), which may improve a desired property, e.g., resistance to nucleases or longer lifetime in blood. Aptamers may be conjugated to other molecules, e.g., a high molecular weight carrier to slow clearance of the aptamer from the circulatory system. Aptamers may be specifically cross-linked to their cognate ligands, e.g., by photo-activation of a cross-linker. (See, e.g., Brody, E.N. and L. Gold (2000) J. Biotechnol. 74:5-13.)

The term "intramer" refers to an aptamer which is expressed in vivo. For example, a vaccinia virus-based RNA expression system has been used to express specific RNA aptamers at high levels in the cytoplasm of leukocytes (Blind, M. et al. (1999) Proc. Natl Acad. Sci. USA 96:3606-3610).

The term "spiegelmer" refers to an aptamer which includes L-DNA, L-RNA, or other left- handed nucleotide derivatives or nucleotide-like molecules. Aptamers containing left-handed nucleotides are resistant to degradation by naturally occurring enzymes, which normally act on substrates containing right-handed nucleotides.

The term "antisense" refers to any composition capable of base-pairing with the "sense" (coding) strand of a specific nucleic acid sequence. Antisense compositions may include DNA; RNA; peptide nucleic acid (PNA); oligonucleotides having modified backbone linkages such as phosphorothioates, methylphosphonates, or benzylphosphonates; oligonucleotides having modified sugar groups such as 2 -methoxyethyl sugars or 2 -methoxyethoxy sugars; or oligonucleotides having modified bases such as 5-methyl cytosine, 2-deoxyuracil, or 7-deaza-2'-deoxyguanosine. Antisense molecules may be produced by any method including chemical synthesis or transcription. Once introduced into a cell, the complementary antisense molecule base-pairs with a naturally occurring nucleic acid sequence produced by the cell to form duplexes which block either transcription or translation. The designation "negative" or "minus" can refer to the antisense strand, and the designation "positive" or "plus" can refer to the sense strand of a reference DNA molecule.

The term "biologically active" refers to a protein having structural, regulatory, or biochemical functions of a naturally occurring molecule. Likewise, "immunologically active" or "immunogenic" refers to the capability of the natural, recombinant, or synthetic OXRD, or of any oligopeptide thereof, to induce a specific immune response in appropriate animals or cells and to bind with specific antibodies.

"Complementary" describes the relationship between two single-stranded nucleic acid sequences that anneal by base-pairing. For example, 5'-AGT-3' pairs with its complement, 3'-TCA-5\

A "composition comprising a given polynucleotide sequence" and a "composition comprising a given amino acid sequence" refer broadly to any composition containing the given polynucleotide or amino acid sequence. The composition may comprise a dry formulation or an aqueous solution. Compositions comprising polynucleotide sequences encoding OXRD or fragments of OXRD may be employed as hybridization probes. The probes may be stored in freeze-dried form and may be associated with a stabilizing agent such as a carbohydrate. In hybridizations, the probe may be deployed in an aqueous solution containing salts (e.g., NaCl), detergents (e.g., sodium dodecyl sulfate; SDS), and other components (e.g., Denhardt's solution, dry milk, salmon sperm DNA, etc.). "Consensus sequence" refers to a nucleic acid sequence which has been subjected to repeated DNA sequence analysis to resolve uncalled bases, extended using the XL-PCR kit (Applied Biosystems, Foster City CA) in the 5' and/or the 3' direction, and resequenced, or which has been assembled from one or more overlapping cDNA, EST, or genomic DNA fragments using a computer program for fragment assembly, such as the GELVTEW fragment assembly system (GCG, Madison WE) or Phrap (University of Washington, Seattle WA). Some sequences have been both extended and assembled to produce the consensus sequence.

"Conservative amino acid substitutions" are those substitutions that are predicted to least interfere with the properties of the original protein, i.e., the structure and especially the function of the protein is conserved and not significantly changed by such substitutions. The table below shows amino acids which may be substituted for an original amino acid in a protein and which are regarded as conservative amino acid substitutions. Original Residue Conservative Substitution Ala Gly, Ser

Arg His, Lys

Asn Asp, Gin, His

Asp Asn, Glu

Cys Ala, Ser Gin Asn, Glu, His

Glu Asp, Gin, His

Gly Ala

His Asn, Arg, Gin, Glu lie Leu, Val Leu lie, Val

Lys Arg, Gin, Glu

Met Leu, lie

Phe His, Met, Leu, Trp, Tyr

Ser Cys, Thr Thr Ser, Val

Trp Phe, Tyr

Tyr His, Phe, Trp Val He, Leu, Thr

Conservative amino acid substitutions generally maintain (a) the structure of the polypeptide backbone in the area of the substitution, for example, as a beta sheet or alpha helical conformation, (b) the charge or hydrophobicity of the molecule at the site of the substitution, and/or (c) the bulk of the side chain.

A "deletion" refers to a change in the amino acid or nucleotide sequence that results in the absence of one or more amino acid residues or nucleotides.

The term "derivative" refers to a chemically modified polynucleotide or polypeptide. Chemical modifications of a polynucleotide can include, for example, replacement of hydrogen by an alkyl, acyl, hydroxyl, or amino group. A derivative polynucleotide encodes a polypeptide which retains at least one biological or immunological function of the natural molecule. A derivative polypeptide is one modified by glycosylation, pegylation, or any similar process that retains at least one biological or immunological function of the polypeptide from which it was derived.

A "detectable label" refers to a reporter molecule or enzyme that is capable of generating a measurable signal and is covalently or noncovalently joined to a polynucleotide or polypeptide.

"Differential expression" refers to increased or upregulated; or decreased, downregulated, or absent gene or protein expression, determined by comparing at least two different samples. Such comparisons may be carried out between, for example, a treated and an untreated sample, or a diseased and a normal sample.

"Exon shuffling" refers to the recombination of different coding regions (exons). Since an exon may represent a structural or functional domain of the encoded protein, new proteins may be assembled through the novel reassortment of stable substructures, thus allowing acceleration of the evolution of new protein functions.

A "fragment" is a unique portion of OXRD or the polynucleotide encoding OXRD which is identical in sequence to but shorter in length than the parent sequence. A fragment may comprise up to the entire length of the defined sequence, minus one nucleotide/amino acid residue. For example, a fragment may comprise from 5 to 1000 contiguous nucleotides or amino acid residues. A fragment used as a probe, primer, antigen, therapeutic molecule, or for other purposes, may be at least 5, 10, 15, 16, 20, 25, 30, 40, 50, 60, 75, 100, 150, 250 or at least 500 contiguous nucleotides or amino acid residues in length. Fragments may be preferentially selected from certain regions of a molecule. For example, a polypeptide fragment may comprise a certain length of contiguous amino acids selected from the first 250 or 500 amino acids (or first 25% or 50%) of a polypeptide as shown in a certain defined sequence. Clearly these lengths are exemplary, and any length that is supported by the specification, including the Sequence Listing, tables, and figures, may be encompassed by the present embodiments.

A fragment of SEQ ED NO:4-6 comprises a region of unique polynucleotide sequence that specifically identifies SEQ ID NO:4-6, for example, as distinct from any other sequence in the genome from which the fragment was obtained. A fragment of SEQ ED NO:4-6 is useful, for example, in hybridization and amplification technologies and in analogous methods that distinguish SEQ ED NO:4-6 from related polynucleotide sequences. The precise length of a fragment of SEQ JD NO:4-6 and the region of SEQ JD NO:4-6 to which the fragment corresponds are routinely determinable by one of ordinary skill in the art based on the intended purpose for the fragment.

A fragment of SEQ JD NO:l-3 is encoded by a fragment of SEQ ED NO:4-6. A fragment of SEQ ID NO: 1-3 comprises a region of unique amino acid sequence that specifically identifies SEQ JD NO: 1-3. For example, a fragment of SEQ JD NO: 1-3 is useful as an immunogenic peptide for the development of antibodies that specifically recognize SEQ ED NO: 1-3. The precise length of a fragment of SEQ JD NO : 1 -3 and the region of SEQ JD NO : 1 -3 to which the fragment corresponds are routinely determinable by one of ordinary skill in the art based on the intended purpose for the fragment.

A "full length" polynucleotide sequence is one containing at least a translation initiation codon (e.g., methionine) followed by an open reading frame and a translation termination codon. A "full length" polynucleotide sequence encodes a "full length" polypeptide sequence.

"Homology" refers to sequence similarity or, interchangeably, sequence identity, between two or more polynucleotide sequences or two or more polypeptide sequences. The terms "percent identity" and "% identity," as applied to polynucleotide sequences, refer to the percentage of residue matches between at least two polynucleotide sequences aligned using a standardized algorithm. Such an algorithm may insert, in a standardized and reproducible way, gaps in the sequences being compared in order to optimize alignment between two sequences, and therefore achieve a more meaningful comparison of the two sequences. Percent identity between polynucleotide sequences may be determined using the default parameters of the CLUSTAL V algorithm as incorporated into the MEGALIGN version 3.12e sequence alignment program. This program is part of the LASERGENE software package, a suite of molecular biological analysis programs (DNASTAR, Madison WE). CLUSTAL V is described in Higgins, D.G. and P.M. Sharp (1989) CABIOS 5:151-153 and in Higgins, D.G. et al. (1992) CABIOS 8:189-191. For pairwise alignments of polynucleotide sequences, the default parameters are set as follows: Ktuple=2, gap penalty=5, window=4, and "diagonals saved"=4. The "weighted" residue weight table is selected as the default. Percent identity is reported by CLUSTAL V as the "percent similarity" between aligned polynucleotide sequences.

Alternatively, a suite of commonly used and freely available sequence comparison algorithms is provided by the National Center for Biotechnology Information (NCBI) Basic Local Alignment

Search Tool (BLAST) (Altschul, S.F. et al. (1990) J. Mol. Biol. 215:403-410), which is available from several sources, including the NCBI, Bethesda, MD, and on the Internet at http://www.ncbi.nlm.nih.gov/BLAST/. The BLAST software suite includes various sequence analysis programs including "blastn," that is used to align a known polynucleotide sequence with other polynucleotide sequences from a variety of databases. Also available is a tool called "BLAST 2 Sequences" that is used for direct pairwise comparison of two nucleotide sequences. "BLAST 2 Sequences" can be accessed and used interactively at htφ://www.ncbi.nlm. h.gov/gor^l2.html. The "BLAST 2 Sequences" tool can be used for both blastn and blastp (discussed below). BLAST programs are commonly used with gap and other parameters set to default settings. For example, to compare two nucleotide sequences, one may use blastn with the "BLAST 2 Sequences" tool Version 2.0.12 (April-21-2000) set at default parameters. Such default parameters may be, for example: Matrix: BLOSUM62 Reward for match: 1 Penalty for mismatch: -2

Open Gap: 5 and Extension Gap: 2 penalties

Gap x drop-off: 50

Expect: 10 Word Size: 11

Filter: on

Percent identity may be measured over the length of an entire defined sequence, for example, as defined by a particular SEQ JD number, or may be measured over a shorter length, for example, over the length of a fragment taken from a larger, defined sequence, for instance, a fragment of at least 20, at least 30, at least 40, at least 50, at least 70, at least 100, or at least 200 contiguous nucleotides. Such lengths are exemplary only, and it is understood that any fragment length supported by the sequences shown herein, in the tables, figures, or Sequence Listing, may be used to describe a length over which percentage identity may be measured.

Nucleic acid sequences that do not show a high degree of identity may nevertheless encode similar amino acid sequences due to the degeneracy of the genetic code. It is understood that changes in a nucleic acid sequence can be made using this degeneracy to produce multiple nucleic acid sequences that all encode substantially the same protein.

The phrases "percent identity" and "% identity," as applied to polypeptide sequences, refer to the percentage of residue matches between at least two polypeptide sequences aligned using a standardized algorithm. Methods of polypeptide sequence alignment are well-known. Some alignment methods take into account conservative amino acid substitutions. Such conservative substitutions, explained in more detail above, generally preserve the charge and_hydrophobicity at the site of substitution, thus preserving the structure (and therefore function) of the polypeptide.

Percent identity between polypeptide sequences may be determined using the default parameters of the CLUSTAL V algorithm as incorporated into the MEGALIGN version 3.12e sequence alignment program (described and referenced above). For pairwise alignments of polypeptide sequences using CLUSTAL V, the default parameters are set as follows: Ktuple=l, gap penalty=3, window=5, and "diagonals saved"=5. The PAM250 matrix is selected as the default residue weight table. As with polynucleotide alignments, the percent identity is reported by CLUSTAL V as the "percent similarity" between aligned polypeptide sequence pairs.

Alternatively the NCBI BLAST software suite may be used. For example, for a pairwise comparison of two polypeptide sequences, one may use the "BLAST 2 Sequences" tool Version 2.0.12 (April-21-2000) with blastp set at default parameters. Such default parameters may be, for example:

Matrix: BLOSUM62

Open Gap: 11 and Extension Gap: 1 penalties

Gap x drop-off: 50 Expect: 10

Word Size: 3

Filter: on

Percent identity may be measured over the length of an entire defined polypeptide sequence, for example, as defined by a particular SEQ JD number, or may be measured over a shorter length, for example, over the length of a fragment taken from a larger, defined polypeptide sequence, for instance, a fragment of at least 15, at least 20, at least 30, at least 40, at least 50, at least 70 or at least 150 contiguous residues. Such lengths are exemplary only, and it is understood that any fragment length supported by the sequences shown herein, in the tables, figures or Sequence Listing, may be used to describe a length over which percentage identity may be measured. "Human artificial chromosomes" (HACs) are linear microchromosomes which may contain

DNA sequences of about 6 kb to 10 Mb in size and which contain all of the elements required for chromosome replication, segregation and maintenance.

The term "humanized antibody" refers to an antibody molecule in which the amino acid sequence in the non-antigen binding regions has been altered so that the antibody more closely resembles a human antibody, and still retains its original binding ability.

"Hybridization" refers to the process by which a polynucleotide strand anneals with a complementary strand through base pairing under defined hybridization conditions. Specific hybridization is an indication that two nucleic acid sequences share a high degree of complementarity. Specific hybridization complexes form under permissive annealing conditions and remain hybridized after the "washing" step(s). The washing step(s) is particularly important in determining the stringency of the hybridization process, with more stringent conditions allowing less non-specific binding, i.e., binding between pairs of nucleic acid strands that are not perfectly matched. Permissive conditions for annealing of nucleic acid sequences are routinely determinable by one of ordinary skill in the art and may be consistent among hybridization experiments, whereas wash conditions may be varied among experiments to achieve the desired stringency, and therefore hybridization specificity. Permissive annealing conditions occur, for example, at 68°C in the presence of about 6 x SSC, about 1% (w/v) SDS, and about 100 μg/ml sheared, denatured salmon sperm DNA.

Generally, stringency of hybridization is expressed, in part, with reference to the temperature under which the wash step is carried out. Such wash temperatures are typically selected to be about 5°C to 20°C lower than the thermal melting point (T^) for the specific sequence at a defined ionic strength and pH. The T_m is the temperature (under defined ionic strength and pH) at which 50% of the target sequence hybridizes to a perfectly matched probe. An equation for calculating T_m and conditions for nucleic acid hybridization are well known and can be found in Sambrook, J. et al. (1989) Molecular Cloning: A Laboratory Manual 2^nd ed., vol. 1-3, Cold Spring Harbor Press, Plainview NY; specifically see volume 2, chapter 9.

High stringency conditions for hybridization between polynucleotides of the present invention include wash conditions of 68°C in the presence of about 0.2 x SSC and about 0.1% SDS, for 1 hour. Alternatively, temperatures of about 65°C, 60°C, 55°C, or 42°C may be used. SSC concentration may be varied from about 0.1 to 2 x SSC, with SDS being present at about 0.1%. Typically, blocking reagents are used to block non-specific hybridization. Such blocking reagents include, for instance, sheared and denatured salmon sperm DNA at about 100-200 μg/ml. Organic solvent, such as formamide at a concentration of about 35-50% v/v, may also be used under particular circumstances, such as for RNADNA hybridizations. Useful variations on these wash conditions will be readily apparent to those of ordinary skill in the ait. Hybridization, particularly under high stringency conditions, may be suggestive of evolutionary similarity between the nucleotides. Such similarity is strongly indicative of a similar role for the nucleotides and their encoded polypeptides.

The term "hybridization complex" refers to a complex formed between two nucleic acid sequences by virtue of the formation of hydrogen bonds between complementary bases. A hybridization complex may be formed in solution (e.g., C₀t or Rot analysis) or formed between one nucleic acid sequence present in solution and another nucleic acid sequence immobilized on a solid support (e.g., paper, membranes, filters, chips, pins or glass slides, or any other appropriate substrate to which cells or their nucleic acids have been fixed). The words "insertion" and "addition" refer to changes in an amino acid or nucleotide sequence resulting in the addition of one or more amino acid residues or nucleotides, respectively. "Immune response" can refer to conditions associated with inflammation, trauma, immune disorders, or infectious or genetic disease, etc. These conditions can be characterized by expression of various factors, e.g., cytokines, chemokines, and other signaling molecules, which may affect cellular and systemic defense systems.

An "immunogenic fragment" is a polypeptide or oligopeptide fragment of OXRD which is capable of eliciting an immune response when introduced into a living organism, for example, a mammal. The term "immunogenic fragment" also includes any polypeptide or oligopeptide fragment of OXRD which is useful in any of the antibody production methods disclosed herein or known in the art.

The term "microarray" refers to an arrangement of a plurality of polynucleotides, polypeptides, or other chemical compounds on a substrate. The terms "element" and "array element" refer to a polynucleotide, polypeptide, or other chemical compound having a unique and defined position on a microarray.

The term "modulate" refers to a change in the activity of OXRD. For example, modulation may cause an increase or a decrease in protein activity, binding characteristics, or any other biological, functional, or immunological properties of OXRD. The phrases "nucleic acid" and "nucleic acid sequence" refer to a nucleotide, oligonucleotide, polynucleotide, or any fragment thereof. These phrases also refer to DNA or RNA of genomic or synthetic origin which may be single-stranded or double-stranded and may represent the sense or the antisense strand, to peptide nucleic acid (PNA), or to any DNA-like or RNA-like material.

"Operably linked" refers to the situation in which a first nucleic acid sequence is placed in a functional relationship with a second nucleic acid sequence. For instance, a promoter is operably linked to a coding sequence if the promoter affects the transcription or expression of the coding sequence. Operably linked DNA sequences may be in close proximity or contiguous and, where necessary to join two protein coding regions, in the same reading frame.

"Peptide nucleic acid" (PNA) refers to an antisense molecule or anti-gene agent which comprises an oligonucleotide of at least about 5 nucleotides in length linked to a peptide backbone of amino acid residues ending in lysine. The terminal lysine confers solubility to the composition. PNAs preferentially bind complementary single stranded DNA or RNA and stop transcript elongation, and may be pegylated to extend their lifespan in the cell.

"Post-translational modification" of an OXRD may involve lipidation, glycosylation, phosphorylation, acetylation, racemization, proteolytic cleavage, and other modifications known in the ait. These processes may occur synthetically or biochemically. Biochemical modifications will vary by cell type depending on the enzymatic milieu of OXRD.

"Probe" refers to nucleic acid sequences encoding OXRD, their complements, or fragments thereof, which are used to detect identical, allelic or related nucleic acid sequences. Probes are isolated oligonucleotides or polynucleotides attached to a detectable label or reporter molecule. Typical labels include radioactive isotopes, ligands, chemiluminescent agents, and enzymes. "Primers" are short nucleic acids, usually DNA oligonucleotides, which may be annealed to a target polynucleotide by complementary base-pairing. The primer may then be extended along the target DNA strand by a DNA polymerase enzyme. Primer pairs can be used for amplification (and identification) of a nucleic acid sequence, e.g., by the polymerase chain reaction (PCR).

Probes and primers as used in the present invention typically comprise at least 15 contiguous nucleotides of a known sequence. In order to enhance specificity, longer probes and primers may also be employed, such as probes and primers that comprise at least 20, 25, 30, 40, 50, 60, 70, 80, 90, 100, or at least 150 consecutive nucleotides of the disclosed nucleic acid sequences. Probes and primers may be considerably longer than these examples, and it is understood that any length supported by the specification, including the tables, figures, and Sequence Listing, may be used. Methods for preparing and using probes and primers are described in the references, for example Sambrook, J. et al. (1989) Molecular Cloning: A Laboratory Manual, 2^nd ed., vol. 1-3, Cold Spring Harbor Press, Plainview NY; Ausubel, F.M. et al. (1987) Current Protocols in Molecular Biology, Greene Publ. Assoc. & Wiley-Intersciences, New York NY; Innis, M. et al. (1990) PCR Protocols, A Guide to Methods and Applications, Academic Press, San Diego CA. PCR primer pairs can be derived from a known sequence, for example, by using computer programs intended for that purpose such as Primer (Version 0.5, 1991, Whitehead Institute for Biomedical Research, Cambridge MA).

Oligonucleotides for use as primers are selected Using software known in the art for such purpose. For example, OLIGO 4.06 software is useful for the selection of PCR primer pairs of up to 100 nucleotides each, and for the analysis of oligonucleotides and larger polynucleotides of up to 5,000 nucleotides from an input polynucleotide sequence of up to 32 kilobases. Similar primer selection programs have incorporated additional features for expanded capabilities. For example, the PrimOU primer selection program (available to the public from the Genome Center at University of Texas South West Medical Center, Dallas TX) is capable of choosing specific primers from megabase sequences and is thus useful for designing primers on a genome- wide scope. The Primer3 primer selection program (available to the public from the Whitehead Lnstitute/MET Center for Genome Research, Cambridge MA) allows the user to input a "mispriming library," in which sequences to avoid as primer binding sites are user-specified. Primer3 is useful, in particular, for the selection of oligonucleotides for microarrays. (The source code for the latter two primer selection programs may also be obtained from their respective sources and modified to meet the user's specific needs.) The PrimeGen program (available to the public from the UK Human Genome Mapping Project Resource Centre, Cambridge UK) designs primers based on multiple sequence alignments, thereby allowing selection of primers that hybridize to either the most conserved or least conserved regions of aligned nucleic acid sequences. Hence, this program is useful for identification of both unique and conserved oligonucleotides and polynucleotide fragments. The oligonucleotides and polynucleotide fragments identified by any of the above selection methods are useful in hybridization technologies, for example, as PCR or sequencing primers, microarray elements, or specific probes to identify fully or partially complementary polynucleotides in a sample of nucleic acids. Methods of oligonucleotide selection are not limited to those described above.

A "recombinant nucleic acid" is a sequence that is not naturally occurring or has a sequence that is made by an artificial combination of two or more otherwise separated segments of sequence. This artificial combination is often accomplished by chemical synthesis or, more commonly, by the artificial manipulation of isolated segments of nucleic acids, e.g., by genetic engineering techniques such as those described in Sambrook, supra. The term recombinant includes nucleic acids that have been altered solely by addition, substitution, or deletion of a portion of the nucleic acid. Frequently, a recombinant nucleic acid may include a nucleic acid sequence operably linked to a promoter sequence. Such a recombinant nucleic acid may be part of a vector that is used, for example, to transform a cell. Alternatively, such recombinant nucleic acids may be part of a viral vector, e.g., based on a vaccinia virus, that could be use to vaccinate a mammal wherein the recombinant nucleic acid is expressed, inducing a protective immunological response in the mammal.

A "regulatory element" refers to a nucleic acid sequence usually derived from untranslated regions of a gene and includes enhancers, promoters, introns, and 5' and 3' untranslated regions (UTRs). Regulatory elements interact with host or viral proteins which control transcription, translation, or RNA stability.

"Reporter molecules" are chemical or biochemical moieties used for labeling a nucleic acid, amino acid, or antibody. Reporter molecules include radionuclides; enzymes; fluorescent, chemiluminescent, or chromogenic agents; substrates; cofactors; inhibitors; magnetic particles; and other moieties known in the art.

An "RNA equivalent," in reference to a DNA sequence, is composed of the same linear sequence of nucleotides as the reference DNA sequence with the exception that all occurrences of the nitrogenous base thymine are replaced with uracil, and the sugar backbone is composed of ribose instead of deoxyribose. The term "sample" is used in its broadest sense. A sample suspected of containing OXRD, nucleic acids encoding OXRD, or fragments thereof may comprise a bodily fluid; an extract from a cell, chromosome, organelle, or membrane isolated from a cell; a cell; genomic DNA, RNA, or cDNA, in solution or bound to a substrate; a tissue; a tissue print; etc. The terms "specific binding" and "specifically binding" refer to that interaction between a protein or peptide and an agonist, an antibody, an antagonist, a small molecule, or any natural or synthetic binding composition. The interaction is dependent upon the presence of a particular structure of the protein, e.g., the antigenic determinant or epitope, recognized by the binding molecule. For example, if an antibody is specific for epitope "A," the presence of a polypeptide comprising the epitope A, or the presence of free unlabeled A, in a reaction containing free labeled A and the antibody will reduce the amount of labeled A that binds to the antibody.

The term "substantially purified" refers to nucleic acid or amino acid sequences that are removed from their natural environment and are isolated or separated, and are at least 60% free, preferably at least 75% free, and most preferably at least 90% free from other components with which they are naturally associated.

A "substitution" refers to the replacement of one or more amino acid residues or nucleotides by different amino acid residues or nucleotides, respectively.

"Substrate" refers to any suitable rigid or semi-rigid support including membranes, filters, chips, slides, wafers, fibers, magnetic or nonmagnetic beads, gels, tubing, plates, polymers, microparticles and capillaries. The substrate can have a variety of surface forms, such as wells, trenches, pins, channels and pores, to which polynucleotides or polypeptides are bound.

A "transcript image" or "expression profile" refers to the collective pattern of gene expression by a particular cell type or tissue under given conditions at a given time. "Transformation" describes a process by which exogenous DNA is introduced into a recipient cell. Transformation may occur under natural or artificial conditions according to various methods well known in the art, and may rely on any known method for the insertion of foreign nucleic acid sequences into a prokaryotic or eukaryotic host cell. The method for transformation is selected based on the type of host cell being transformed and may include, but is not limited to, bacteriophage or viral infection, electroporation, heat shock, lipofection, and particle bombardment. The term "transformed cells" includes stably transformed cells in which the inserted DNA is capable of replication either as an autonomously replicating plasmid or as part of the host chromosome, as well as transiently transformed cells which express the inserted DNA or RNA for limited periods of time. A "transgenic organism," as used herein, is any organism, including but not limited to animals and plants, in which one or more of the cells of the organism contains heterologous nucleic acid introduced by way of human intervention, such as by transgenic techniques well known in the art. The nucleic acid is introduced into the cell, directly or indirectly by introduction into a precursor of the cell, by way of deliberate genetic manipulation, such as by microinjection or by infection with a recombinant virus. The term genetic manipulation does not include classical cross-breeding, or in vitro fertilization, but rather is directed to the introduction of a recombinant DNA molecule. The transgenic organisms contemplated in accordance with the present invention include bacteria, cyanobacteria, fungi, plants and animals. The isolated DNA of the present invention can be introduced into the host by methods known in the art, for example infection, transfection, transformation or transconjugation. Techniques for transferring the DNA of the present invention into such organisms are widely known and provided in references such as Sambrook et al. (1989), supra.

A "variant" of a particular nucleic acid sequence is defined as a nucleic acid sequence having at least 40% sequence identity to the particular nucleic acid sequence over a certain length of one of the nucleic acid sequences using blastn with the "BLAST 2 Sequences" tool Version 2.0.9 (May-07-1999) set at default parameters. Such a pair of nucleic acids may show, for example, at least 50%, at least 60%, at least 70%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, or at least 99% or greater sequence identity over a certain defined length. A variant may be described as, for example, an "allelic" (as defined above), "splice," "species," or "polymorphic" variant. A splice variant may have significant identity to a reference molecule, but will generally have a greater or lesser number of polynucleotides due to alternate splicing of exons during mRNA processing. The corresponding polypeptide may possess additional functional domains or lack domains that are present in the reference molecule. Species variants are polynucleotide sequences that vary from one species to another. The resulting polypeptides will generally have significant amino acid identity relative to each other. A polymorphic variant is a variation in the polynucleotide sequence of a particular gene between individuals of a given species. Polymorphic variants also may encompass "single nucleotide polymo hisms" (SNPs) in which the polynucleotide sequence varies by one nucleotide base. The presence of SNPs may be indicative of, for example, a certain population, a disease state, or a propensity for a disease state.

A "variant" of a particular polypeptide sequence is defined as a polypeptide sequence having at least 40% sequence identity to the particular polypeptide sequence over a certain length of one of the polypeptide sequences using blastp with the "BLAST 2 Sequences" tool Version 2.0.9 (May-07- 1999) set at default parameters. Such a pair of polypeptides may show, for example, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, or at least 99% or greater sequence identity over a certain defined length of one of the polypeptides. THE INVENTION

The invention is based on the discovery of new human oxidoreductases (OXRD), the polynucleotides encoding OXRD, and the use of these compositions for the diagnosis, treatment, or prevention of cell proliferative, neurological, metabolic, and smooth muscle disorders. Table 1 summarizes the nomenclature for the full length polynucleotide and polypeptide sequences of the invention. Each polynucleotide and its corresponding polypeptide are correlated to a single Incyte project identification number (Encyte Project JD). Each polypeptide sequence is denoted by both a polypeptide sequence identification number (Polypeptide SEQ ED NO:) and an Incyte polypeptide sequence number (Encyte Polypeptide ED) as shown. Each polynucleotide sequence is denoted by both a polynucleotide sequence identification number (Polynucleotide SEQ ED NO:) and an Incyte polynucleotide consensus sequence number (Incyte Polynucleotide JD) as shown.

Table 2 shows sequences with homology to the polypeptides of the invention as identified by BLAST analysis against the GenBank protein (genpept) database. Columns 1 and 2 show the polypeptide sequence identification number (Polypeptide SEQ ED NO:) and the corresponding Incyte polypeptide sequence number (Incyte Polypeptide D) for polypeptides of the invention. Column 3 shows the GenBank identification number (GenBank ID NO:) of the nearest GenBank homolog. Column 4 shows the probability scores for the matches between each polypeptide and its homolog(s). Column 5 shows the annotation of the GenBank homolog(s) along with relevant citations where applicable, all of which are expressly incorporated by reference herein. Table 3 shows various structural features of the polypeptides of the invention. Columns 1 and 2 show the polypeptide sequence identification number (SEQ ED NO:) and the corresponding Incyte polypeptide sequence number (Encyte Polypeptide ED) for each polypeptide of the invention. Column 3 shows the number of amino acid residues in each polypeptide. Column 4 shows potential phosphorylation sites, and column 5 shows potential glycosylation sites, as determined by the MOTIFS program of the GCG sequence analysis software package (Genetics Computer Group, Madison WT). Column 6 shows amino acid residues comprising signature sequences, domains, and motifs. Column 7 shows analytical methods for protein stracture/function analysis and in some cases, searchable databases to which the analytical methods were applied.

Together, Tables 2 and 3 summarize the properties of polypeptides of the invention, and these properties establish that the claimed polypeptides are oxidoreductases. For example, SEQ JD NO:l is 93% identical to human MP dehydrogenase type 1 (GenBank JD g307067) as determined by the Basic Local Alignment Search Tool (BLAST). (See Table 2.) The BLAST probability score is 2.7e- 248, which indicates the probability of obtaining the observed polypeptide sequence alignment by chance. SEQ ED NO:l also contains an MP dehydrogenase/GMP reductase C-terminal domain and an EMP dehydrogenase/GMP reductase N-terminal domain as determined by searching for statistically significant matches in the hidden Markov model (HMM)-based PFAM database of conserved protein family domains. (See Table 3.) Data from BLIMPS, MOTEFS, and PROFILES CAN analyses provide further corroborative evidence that SEQ ED NO: 1 is an IMP dehydrogenase. En an alternative example, SEQ ID NO:3 is 28% identical to mouse 4- hydroxyphenylpyravate dioxygenase (GenBank ED g849053) as determined by BLAST, with a probability score of 9.1e-22. (See Table 2.) SEQ ED NO:3 also contains a 4-hydroxyphenylpyravate dioxygenase C terminal domain as determined by searching for statistically significant matches in the HMM-based PFAM database of conserved protein family domains. (See Table 3.) SEQ ED NO:2 was analyzed and annotated in a similar manner. The algorithms and parameters for the analysis of SEQ JD NO:l-3 are described in Table 7.

As shown in Table 4, the full length polynucleotide sequences of the present invention were assembled using cDNA sequences or coding (exon) sequences derived from genomic DNA, or any combination of these two types of sequences. Column 1 lists the polynucleotide sequence identification number (Polynucleotide SEQ JD NO:), the corresponding Incyte polynucleotide consensus sequence number (Incyte ED) for each polynucleotide of the invention, and the length of each polynucleotide sequence in basepairs. Column 2 shows the nucleotide start (5') and stop (3') positions of the cDNA and/or genomic sequences used to assemble the full length polynucleotide sequences of the invention, and of fragments of the polynucleotide sequences which are useful, for example, in hybridization or amplification technologies that identify SEQ JD NO:4-6 or that distinguish between SEQ ED NO:4-6 and related polynucleotide sequences.

The polynucleotide fragments described in Column 2 of Table 4 may refer specifically, for example, to Incyte cDNAs derived from tissue-specific cDNA libraries or from pooled cDNA libraries. Alternatively, the polynucleotide fragments described in column 2 may refer to GenBank cDNAs or ESTs which contributed to the assembly of the full length polynucleotide sequences. In addition, the polynucleotide fragments described in column 2 may identify sequences derived from the ENSEMBL (The Sanger Centre, Cambridge, UK) database (i.e., those sequences including the designation "ENST"). Alternatively, the polynucleotide fragments described in column 2 may be derived from the NCBI RefSeq Nucleotide Sequence Records Database (i e. , those sequences including the designation "NM" or "NT") or the NCBI RefSeq Protein Sequence Records (i.e., those sequences including the designation "NP"). Alternatively, the polynucleotide fragments described in column 2 may refer to assemblages of both cDNA and Genscan-predicted exons brought together by an "exon stitching" algorithm. For example, a polynucleotide sequence identified as FL_XXXXXX_N₁_N₂_YYYYY_N₃_N₄ represents a "stitched" sequence in which XXXXXX is the identification number of the cluster of sequences to which the algorithm was applied, and YYYYY s the number of the prediction generated by the algorithm, and N _z3.,., if present, represent specific exons that may have been manually edited during analysis (See Example V). Alternatively, the polynucleotide fragments in column 2 may refer to assemblages of exons brought together by an "exon-stretching" algorithm. For example, a polynucleotide sequence identified as FLXXXXXX_gAAAAA_gBBBBB_ϊ_Nis a "stretched" sequence, with XXXXXX being the Incyte project identification number, gAAAAA being the GenBank identification number of the human genomic sequence to which the "exon-stretching" algorithm was applied, gBBBBB being the GenBank identification number or ΝCBI RefSeq identification number of the nearest GenBank protein homolog, and N referring to specific exons (See Example V). In instances where a RefSeq sequence was used as a protein homolog for the "exon-stretching" algorithm, a RefSeq identifier (denoted by "ΝM," "ΝP," or "NT") may be used in place of the GenBank identifier (i.e., gBBBBB). Alternatively, a prefix identifies component sequences that were hand-edited, predicted from genomic DNA sequences, or derived from a combination of sequence analysis methods. The following Table lists examples of component sequence prefixes and corresponding sequence analysis methods associated with the prefixes (see Example IV and Example V).

In some cases, Incyte cDNA coverage redundant with the sequence coverage shown in Table 4 was obtained to confirm the final consensus polynucleotide sequence, but the relevant Incyte cDNA identification numbers are not shown.

Table 5 shows the representative cDNA libraries for those full length polynucleotide sequences which were assembled using Incyte cDNA sequences. The representative cDNA library is the Incyte cDNA library which is most frequently represented by the Incyte cDNA sequences which were used to assemble and confirm the above polynucleotide sequences. The tissues and vectors which were used to construct the cDNA libraries shown in Table 5 are described in Table 6. The invention also encompasses OXRD variants. A preferred OXRD variant is one which has at least about 80%, or alternatively at least about 90%, or even at least about 95% amino acid sequence identity to the OXRD amino acid sequence, and which contains at least one functional or structural characteristic of OXRD.

The invention also encompasses polynucleotides which encode OXRD. In a particular embodiment, the invention encompasses a polynucleotide sequence comprising a sequence selected from the group consisting of SEQ JD NO:4-6, which encodes OXRD. The polynucleotide sequences of SEQ JD NO:4-6, as presented in the Sequence Listing, embrace the equivalent RNA sequences, wherein occurrences of the nitrogenous base thymine are replaced with uracil, and the sugar backbone is composed of ribose instead of deoxyribose.

The invention also encompasses a variant of a polynucleotide sequence encoding OXRD. In particular, such a variant polynucleotide sequence will have at least about 70%, or alternatively at least about 85%, or even at least about 95% polynucleotide sequence identity to the polynucleotide sequence encoding OXRD. A particular aspect of the invention encompasses a variant of a polynucleotide sequence comprising a sequence selected from the group consisting of SEQ JD NO:4- 6 which has at least about 70%, or alternatively at least about 85%, or even at least about 95% polynucleotide sequence identity to a nucleic acid sequence selected from the group consisting of SEQ JD NO:4-6. Any one of the polynucleotide variants described above can encode an amino acid sequence which contains at least one functional or structural characteristic of OXRD.

In addition, or in the alternative, a polynucleotide variant of the invention is a splice variant of a polynucleotide sequence encoding OXRD. A splice variant may have portions which have significant sequence identity to the polynucleotide sequence encoding OXRD, but will generally have a greater or lesser number of polynucleotides due to additions or deletions of blocks of sequence arising from alternate splicing of exons during mRNA processing. A splice variant may have less than about 70%, or alternatively less than about 60%, or alternatively less than about 50% polynucleotide sequence identity to the polynucleotide sequence encoding OXRD over its entire length; however, portions of the splice variant will have at least about 70%, or alternatively at least about 85%, or alternatively at least about 95%, or alternatively 100% polynucleotide sequence identity to portions of the polynucleotide sequence encoding OXRD. Any one of the splice variants described above can encode an amino acid sequence which contains at least one functional or structural characteristic of OXRD.

It will be appreciated by those skilled in the art that as a result of the degeneracy of the genetic code, a multitude of polynucleotide sequences encoding OXRD, some bearing minimal similarity to the polynucleotide sequences of any known and naturally occurring gene, may be produced. Thus, the invention contemplates each and every possible variation of polynucleotide sequence that could be made by selecting combinations based on possible codon choices. These combinations are made in accordance with the standard triplet genetic code as applied to the polynucleotide sequence of naturally occurring OXRD, and all such variations are to be considered as being specifically disclosed. Although nucleotide sequences which encode OXRD and its variants are generally capable of hybridizing to the nucleotide sequence of the naturally occurring OXRD under appropriately selected conditions of stringency, it may be advantageous to produce nucleotide sequences encoding OXRD or its derivatives possessing a substantially different codon usage, e.g., inclusion of non- naturally occurring codons. Codons may be selected to increase the rate at which expression of the peptide occurs in a particular prokaryotic or eukaryotic host in accordance with the frequency with which particular codons are utilized by the host. Other reasons for substantially altering the nucleotide sequence encoding OXRD and its derivatives without altering the encoded amino acid sequences include the production of RNA transcripts having more desirable properties, such as a greater half-life, than transcripts produced from the naturally occurring sequence. The invention also encompasses production of DNA sequences which encode OXRD and

OXRD derivatives, or fragments thereof, entirely by synthetic chemistry. After production, the synthetic sequence may be inserted into any of the many available expression vectors and cell systems using reagents well known in the art. Moreover, synthetic chemistry may be used to introduce mutations into a sequence encoding OXRD or any fragment thereof. Also encompassed by the invention are polynucleotide sequences that are capable of hybridizing to the claimed polynucleotide sequences, and, in particular, to those shown in SEQ ID NO:4-6 and fragments thereof under various conditions of stringency. (See, e.g., Wahl, G.M. and S.L. Berger (1987) Methods Enzymol. 152:399-407; Kimmel, A.R. (1987) Methods Enzymol. 152:507-511.) Hybridization conditions, including annealing and wash conditions, are described in "Definitions."

Methods for DNA sequencing are well known in the art and may be used to practice any of the embodiments of the invention. The methods may employ such enzymes as the Klenow fragment of DNA polymerase I, SEQUENASE (US Biochemical, Cleveland OH), Taq polymerase (Applied Biosystems), thermostable T7 polymerase (Amersham Pharmacia Biotech, Piscataway NJ), or combinations of polymerases and proofreading exonucleases such as those found in the ELONGASE amplification system (Life Technologies, G thersburg MD). Preferably, sequence preparation is automated with machines such as the MICROLAB 2200 liquid transfer system (Hamilton, Reno NV), PTC200 thermal cycler (MJ Research, Watertown MA) and ABI CATALYST 800 thermal cycler (Applied Biosystems). Sequencing is then carried out using either the ABI 373 or 377 DNA sequencing system (Applied Biosystems), the MEGABACE 1000 DNA sequencing system (Molecular Dynamics, Sunnyvale CA), or other systems known in the art. The resulting sequences are analyzed using a variety of algorithms which are well known in the art. (See, e.g., Ausubel, F.M. (1997) Short Protocols in Molecular Biology, John Wiley & Sons, New York NY, unit 7.7; Meyers, R.A. (1995) Molecular Biology and Biotechnology, Wiley VCH, New York NY, pp. 856-853.)

The nucleic acid sequences encoding OXRD may be extended utilizing a partial nucleotide sequence and employing various PCR-based methods known in the art to detect upstream sequences, such as promoters and regulatory elements. For example, one method which may be employed, restriction-site PCR, uses universal and nested primers to amplify unknown sequence from genomic DNA within a cloning vector. (See, e.g., Sarkar, G. (1993) PCR Methods Applic. 2:318-322.) Another method, inverse PCR, uses primers that extend in divergent directions to amplify unknown sequence from a circularized template. The template is derived from restriction fragments comprising a known genomic locus and surrounding sequences. (See, e.g., Triglia, T. et al. (1988) Nucleic Acids Res. 16:8186.) A third method, capture PCR, involves PCR amplification of DNA fragments adjacent to known sequences in human and yeast artificial chromosome DNA. (See, e.g., Lagerstrom, M. et al. (1991) PCR Methods Applic. 1:111-11 .) In this method, multiple restriction enzyme digestions and ligations may be used to insert an engineered double-stranded sequence into a region of unknown sequence before performing PCR. Other methods which may be used to retrieve unknown sequences are known in the art. (See, e.g., Parker, J.D. et al. (1991) Nucleic Acids Res. 19:3055-3060). Additionally, one may use PCR, nested primers, and PROMOTERFTNDER libraries (Clontech, Palo Alto CA) to walk genomic DNA. This procedure avoids the need to screen libraries and is useful in finding intron/exon junctions. For all PCR-based methods, primers may be designed using commercially available software, such as OLIGO 4.06 primer analysis software (National Biosciences, Plymouth MN) or another appropriate program, to be about 22 to 30 nucleotides in length, to have a GC content of about 50% or more, and to anneal to the template at temperatures of about 68°C to 72°C

When screening for full length cDNAs, it is preferable to use libraries that have been size-selected to include larger cDNAs. In addition, random-primed libraries, which often include sequences containing the 5' regions of genes, are preferable for situations in which an oligo d(T) library does not yield a full-length cDNA. Genomic libraries may be useful for extension of sequence into 5' non-transcribed regulatory regions. Capillary electrophoresis systems which are commercially available may be used to analyze the size or confirm the nucleotide sequence of sequencing or PCR products. In particular, capillary sequencing may employ flowable polymers for electrophoretic separation, four different nucleotide- specific, laser-stimulated fluorescent dyes, and a charge coupled device camera for detection of the emitted wavelengths. Output/light intensity may be converted to electrical signal using appropriate software (e.g., GENOTYPER and SEQUENCE NAVIGATOR, AppUed Biosystems), and the entire process from loading of samples to computer analysis and electronic data display may be computer controlled. Capillary electrophoresis is especially preferable for sequencing small DNA fragments which may be present in Umited amounts in a particular sample.

In another embodiment of the invention, polynucleotide sequences or fragments thereof which encode OXRD may be cloned in recombinant DNA molecules that direct expression of

OXRD, or fragments or functional equivalents thereof, in appropriate host cells. Due to the inherent degeneracy of the genetic code, other DNA sequences which encode substantiaUy the same or a functionally equivalent amino acid sequence may be produced and used to express OXRD.

The nucleotide sequences of the present invention can be engineered using methods generally known in the art in order to alter OXRD-encoding sequences for a variety of purposes including, but not Umited to, modification of the cloning, processing, and/or expression of the gene product. DNA shuffling by random fragmentation and PCR reassembly of gene fragments and synthetic oUgonucleotides may be used to engineer the nucleotide sequences. For example, oUgonucleotide- mediated site-directed mutagenesis may be used to introduce mutations that create new restriction sites, alter glycosylation patterns, change codon preference, produce spUce variants, and so forth.

The nucleotides of the present invention may be subjected to DNA shuffling techniques such as MOLECULARBREEDING (Maxygen Inc., Santa Clara CA; described in U.S. Patent No. 5,837,458; Chang, C.-C et al. (1999) Nat. Biotechnol. 17:793-797; Christians, F.C et al. (1999) Nat. Biotechnol. 17:259-264; and Crameri, A. et al. (1996) Nat. Biotechnol. 14:315-319) to alter or improve the biological properties of OXRD, such as its biological or enzymatic activity or its abiUty to bind to other molecules or compounds. DNA shuffling is a process by which a Ubrary of gene variants is produced using PCR-mediated recombination of gene fragments. The Ubrary is then subjected to selection or screening procedures that identify those gene variants with the desired properties. These preferred variants may then be pooled and further subjected to recursive rounds of DNA shuffling and selection/screening. Thus, genetic diversity is created through "artificial" breeding and rapid molecular evolution. For example, fragments of a single gene containing random point mutations may be recombined, screened, and then reshuffled until the desired properties are optimized. Alternatively, fragments of a given gene may be recombined with fragments of homologous genes in the same gene family, either from the same or different species, thereby maximizing the genetic diversity of multiple naturally occurring genes in a directed and controllable manner.

In another embodiment, sequences encoding OXRD may be synthesized, in whole or in part, using chemical methods well known in the art. (See, e.g., Carathers, M.H. et al. (1980) Nucleic Acids Symp. Ser. 7:215-223; and Horn, T. et al. (1980) Nucleic Acids Symp. Ser. 7:225-232.) Alternatively, OXRD itself or a fragment thereof may be synthesized using chemical methods. For example, peptide synthesis can be performed using various solution-phase or soUd-phase techniques. (See, e.g., Creighton, T. (1984) Proteins, Structures and Molecular Properties, WH Freeman, New York NY, pp. 55-60; and Roberge, J.Y. et al. (1995) Science 269:202-204.) Automated synthesis may be achieved using the ABI 431 A peptide synthesizer (AppUed Biosystems). Additionally, the amino acid sequence of OXRD, or any part thereof, may be altered during direct synthesis and/or -combined with sequences from other proteins, or any part thereof, to produce a variant polypeptide or a polypeptide having a sequence of a naturally occurring polypeptide. The peptide may be substantially purified by preparative high performance Uquid chromatography. (See, e.g., Chiez, R.M. and F.Z. Regnier (1990) Methods Enzymol. 182:392-421.) The composition of the synthetic peptides may be confirmed by amino acid analysis or by sequencing. (See, e.g., Creighton, supra, pp. 28-53.)

In order to express a biologically active OXRD, the nucleotide sequences encoding OXRD or derivatives thereof may be inserted into an appropriate expression vector, i.e., a vector which contains the necessary elements for transcriptional and translational control of the inserted coding sequence in a suitable host. These elements include regulatory sequences, such as enhancers, constitutive and inducible promoters, and 5' and 3' untranslated regions in the vector and in polynucleotide sequences encoding OXRD. Such elements may vary in their strength and specificity. Specific initiation signals may also be used to achieve more efficient translation of sequences encoding OXRD. Such signals include the ATG initiation codon and adjacent sequences, e.g. the Kozak sequence. In cases where sequences encoding OXRD and its initiation codon and upstream regulatory sequences are inserted into the appropriate expression vector, no additional transcriptional or translational control signals may be needed. However, in cases where only coding sequence, or a fragment thereof, is inserted, exogenous translational control signals including an in-frame ATG initiation codon should be provided by the vector. Exogenous translational elements and initiation codons may be of various origins, both natural and synthetic. The efficiency of expression may be enhanced by the inclusion of enhancers appropriate for the particular host cell system used. (See, e.g., Scharf, D. et al (1994) Results Probl. Cell Differ. 20:125-162.)

Methods which are well known to those skilled in the art may be used to construct expression vectors containing sequences encoding OXRD and appropriate transcriptional and translational control elements. These methods include in vitro recombinant DNA techniques, synthetic techniques, and in vivo genetic recombination. (See, e.g., Sambrook, J. et al. (1989) Molecular Cloning, A

Laboratory Manual, Cold Spring Harbor Press, Plainview NY, ch. 4, 8, and 16-17; Ausubel, F.M. et al. (1995) Current Protocols in Molecular Biology, John Wiley & Sons, New York NY, ch. 9, 13, and 16.)

A variety of expression vector/host systems may be utilized to contain and express sequences encoding OXRD. These include, but are not Umited to, microorganisms such as bacteria transformed with recombinant bacteriophage, plasmid, or cosmid DNA expression vectors; yeast transformed with yeast expression vectors; insect cell systems infected with viral expression vectors (e.g., baculoviras); plant cell systems transformed with viral expression vectors (e.g., cauUflower mosaic virus, CaMV, or tobacco mosaic virus, TMV) or with bacterial expression vectors (e.g., Ti or pBR322 plasmids); or animal cell systems. (See, e.g., Sambrook, supra: Ausubel, supra; Van Heeke, G. and S.M. Schuster (1989) J. Biol. Chem. 264:5503-5509; Engelhard, E.K. et al. (1994) Proc. Natl. Acad. Sci. USA 91:3224-3227; Sandig, V. et al. (1996) Hum. Gene Ther. 7:1937-1945; Takamatsu, N. (1987) EMBO J. 6:307-311 : The McGraw Hill Yearbook of Science and Technology (1992) McGraw Hill, New York NY, pp. 191-196; Logan, J. and T. Shenk (1984) Proc. Natl. Acad. Sci. USA 81 :3655-3659; and Harrington, J.J. et al (1997) Nat. Genet. 15:345-355.) Expression vectors derived from retrovirases, adenoviruses, or herpes or vaccinia viruses, or from various bacterial plasmids, may be used for deUvery of nucleotide sequences to the targeted organ, tissue, or cell population. (See, e.g., Di Nicola, M. et al. (1998) Cancer Gen. Ther. 5(6):350-356; Yu, M. et al (1993) Proc. Natl. Acad. Sci. USA 90(13):6340-6344; Buller, R.M. et al. (1985) Nature 317(6040):813-815; McGregor, D.P. et al (1994) Mol. Immunol. 31(3):219-226; and Verma, I.M. and N. Somia (1997) Nature 389:239-242.) The invention is not Umited by the host ceU employed.

In bacterial systems, a number of cloning and expression vectors may be selected depending upon the use intended for polynucleotide sequences encoding OXRD. For example, routine cloning, subcloning, and propagation of polynucleotide sequences encoding OXRD can be achieved using a multifunctional E. coU vector such as PBLUESCREPT (Stratagene, La Jolla CA) or PSPORT1 plasmid (Life Technologies). Ligation of sequences encoding OXRD into the vector's multiple cloning site disrupts the lacL gene, allowing a colorimetric screening procedure for identification of transformed bacteria containing recombinant molecules. En addition, these vectors may be useful for in vitro transcription, dideoxy sequencing, single strand rescue with helper phage, and creation of nested deletions in the cloned sequence. (See, e.g., Van Heeke, G. and S.M. Schuster (1989) J. Biol. Chem. 264:5503-5509.) When large quantities of OXRD are needed, e.g. for the production of antibodies, vectors which direct high level expression of OXRD may be used. For example, vectors containing the strong, inducible SP6 or T7 bacteriophage promoter may be used.

Yeast expression systems may be used for production of OXRD. A number of vectors containing constitutive or inducible promoters, such as alpha factor, alcohol oxidase, and PGH promoters, may be used in the yeast Saccharomyces cerevisiae or Pichia pastoris. In addition, such vectors direct either the secretion or intraceUular retention of expressed proteins and enable integration of foreign sequences into the host genome for stable propagation. (See, e.g., Ausubel, 1995, supra; Bitter, G.A. et al. (1987) Methods Enzymol. 153:516-544; and Scorer, CA. et al. (1994) Bio/Technology 12:181-184.)

Plant systems may also be used for expression of OXRD. Transcription of sequences encoding OXRD may be driven by viral promoters, e.g., the 35S and 19S promoters of CaMV used alone or in combination with the omega leader sequence from TMV (Takamatsu, N. (1987) EMBO J. 6:307-311). Alternatively, plant promoters such as the small subunit of RUBISCO or heat shock promoters maybe used. (See, e.g., Corazzi, G et al. (1984) EMBO J. 3:1671-1680; BrogUe, R et al. (1984) Science 224:838-843; and Winter, J. et al. (1991) Results Probl Cell Differ. 17:85-105.) These constructs can be introduced into plant cells by direct DNA transformation or pathogen-mediated transfection. (See, e.g.. The McGraw Hill Yearbook of Science and Technology (1992) McGraw Hill, New York NY, pp. 191-196.)

In mammaUan cells, a number of viral-based expression systems may be utilized. In cases where an adenovirus is used as an expression vector, sequences encoding OXRD may be Ugated into an adenovirus transcription/translation complex consisting of the late promoter and tripartite leader sequence. Insertion in a non-essential El or E3 region of the viral genome may be used to obtain infective virus which expresses OXRD in host cells. (See, e.g., Logan, J. and T. Shenk (1984) Proc. Natl. Acad. Sci. USA 81:3655-3659.) In addition, transcription enhancers, such as the Rous sarcoma virus (RSV) enhancer, may be used to increase expression in mammaUan host ceUs. SV40 or EB V- based vectors may also be used for high-level protein expression.

Human artificial chromosomes (HACs) may also be employed to deUver larger fragments of DNA than can be contained in and expressed from a plasmid. HACs of about 6 kb to 10 Mb are constructed and deUvered via conventional deUvery methods (Uposomes, polycationic amino polymers, or vesicles) for therapeutic purposes. (See, e.g., Harrington, J.J. et al. (1997) Nat. Genet. 15:345- 355.)

For long term production of recombinant proteins in mammaUan systems, stable expression of OXRD in cell Unes is preferred. For example, sequences encoding OXRD can be transformed into ceU Unes using expression vectors which may contain viral origins of repUcation and/or endogenous expression elements and a selectable marker gene on the same or on a separate vector. Following the introduction of the vector, cells may be aUowed to grow for about 1 to 2 days in enriched media before being switched to selective media. The purpose of the selectable marker is to confer resistance to a selective agent, and its presence allows growth and recoveiy of ceUs which successfully express the introduced sequences. Resistant clones of stably transformed cells may be propagated using tissue culture techniques appropriate to the cell type.

Any number of selection systems may be used to recover transformed cell Unes. These include, but are not Umited to, the herpes simplex virus thymidine kinase and adenine phosphoribosyltransferase genes, for use in tk and apr cells, respectively. (See, e.g., Wigler, M. et al. (1977) CeU 11:223-232; Lowy, E. et al (1980) Cell 22:817-823.) Also, antimetaboUte, antibiotic, or herbicide resistance can be used as the basis for selection. For example, dhfi' confers resistance to methotrexate; neo confers resistance to the aminoglycosides neomycin and G-418; and als and pat confer resistance to cMorsulfuron and phosphinotricin acetyltransferase, respectively. (See, e.g., Wigler, M. et al. (1980) Proc. Natl Acad. Sci. USA 77:3567-3570; Colbere-Garapin, F. et al. (1981) J. Mol. Biol. 150:1-14.) Additional selectable genes have been described, e.g., trpB and hisD, which alter ceUular requirements for metaboUtes. (See, e.g., Hartman, S.C. and R.C. MuUigan (1988) Proc. Natl. Acad. Sci. USA 85:8047-8051.) Visible markers, e.g., anthocyanins, green fluorescent proteins (GFP; Clontech), β glucuronidase and its substrate β-glucuronide, or luciferase and its substrate luciferin may be used. These markers can be used not only to identify transformants, but also to quantify the amount of transient or stable protein expression attributable to a specific vector system. (See, e.g., Rhodes, CA. (1995) Methods Mol. Biol. 55:121-131.)

Although the presence/absence of marker gene expression suggests that the gene^'of interest is also present, the presence and expression of the gene may need to be confirmed. For example, if the sequence encoding OXRD is inserted within a marker gene sequence, transformed ceUs containing sequences encoding OXRD can be identified by the absence of marker gene function. Alternatively, a marker gene can be placed in tandem with a sequence encoding OXRD under the control of a single promoter. Expression of the marker gene in response to induction or selection usuaUy indicates expression of the tandem gene as well. In general host ceUs that contain the nucleic acid sequence encoding OXRD and that express OXRD may be identified by a variety of procedures known to those of skill in the art. These procedures include, but are not Umited to, DNA-DNA or DNA-RNA hybridizations, PCR ampUfication, and protein bioassay or immunoassay techniques which include membrane, solution, or chip based technologies for the detection and/or quantification of nucleic acid or protein sequences. Immunological methods for detecting and measuring the expression of OXRD using either specific polyclonal or monoclonal antibodies are known in the art. Examples of such techniques include enzyme-Unked immunosorbent assays (ELISAs), radioimmunoassays (RIAs), and fluorescence activated ceU sorting (FACS). A two-site, monoclonal-based immunoassay utiUzing monoclonal antibodies reactive to two non-interfering epitopes on OXRD is preferred, but a competitive binding assay may be employed. These and other assays are well known in the art.

(See, e.g., Hampton, R et al. (1990) Serological Methods, a Laboratory Manual, APS Press, St. Paul MN, Sect. IV; CoUgan, J.E. et al. (1997) Current Protocols in Immunology, Greene Pub. Associates and Wiley-Interscience, New York NY; and Pound, J.D. (1998) lmmunochemical Protocols, Humana Press, Totowa NJ.) A wide variety of labels and conjugation techniques are known by those skiUed in the art and may be used in various nucleic acid and amino acid assays. Means for producing labeled hybridization or PCR probes for detecting sequences related to polynucleotides encoding OXRD include oUgolabeUng, nick translation, end-labeUng, or PCR ampUfication using a labeled nucleotide. Alternatively, the sequences encoding OXRD, or any fragments thereof, may be cloned into a vector for the production of an mRNA probe. Such vectors are known in the art, are commercially available, and may be used to synthesize RNA probes in vitro by addition of an appropriate RNA polymerase such as T7, T3, or SP6 and labeled nucleotides. These procedures may be conducted using a variety of commerciaUy available kits, such as those provided by Amersham Pharmacia Biotech, Promega (Madison WE), and US Biochemical. Suitable reporter molecules or labels which may be used for ease of detection include radionucUdes, enzymes, fluorescent, chemiluminescent, or chromogenic agents, as weU as substrates, cofactors, inhibitors, magnetic particles, and the Uke.

Host cells transformed with nucleotide sequences encoding OXRD may be cultured under conditions suitable for the expression and recovery of the protein from ceU culture. The protein produced by a transformed cell may be secreted or retained intraceUularly depending on the sequence and/or the vector used. As will be understood by those of skill in the art, expression vectors containing polynucleotides which encode OXRD may be designed to contain signal sequences which direct secretion of OXRD through a prokaryotic or eukaryotic cell membrane. In addition, a host cell strain may be chosen for its abiUty to modulate expression of the inserted sequences or to process the expressed protein in the desired fashion. Such modifications of the polypeptide include, but are not Umited to, acetylation, carboxylation, glycosylation, phosphorylation, Upidation, and acylation. Post-translational processing which cleaves a "prepro" or "pro" form of the protein may also be used to specify protein targeting, folding, and/or activity. Different host cells which have specific ceUular machinery and characteristic mechanisms for post-translational activities (e.g., CHO, HeLa, MDCK, HEK293, and WI38) are available from the American Type Culture Collection (ATCC, Manassas VA) and may be chosen to ensure the correct modification and processing of the foreign protein.

In another embodiment of the invention, natural, modified, or recombinant nucleic acid sequences encoding OXRD may be Ugated to a heterologous sequence resulting in translation of a fusion protein in any of the aforementioned host systems. For example, a chimeric OXRD protein containing a heterologous moiety that can be recognized by a commerciaUy available antibody may faciUtate the screening of peptide Ubraries for inhibitors of OXRD activity. Heterologous protein and peptide moieties may also faciUtate purification of fusion proteins using commercially available affinity matrices. Such moieties include, but are not Umited to, glutathione S-transferase (GST), maltose binding protein (MBP), thioredoxin (Trx), calmoduUn binding peptide (CBP), 6-His, FLAG, c-myc, and hemagglutinin (HA). GST, MBP, Trx, CBP, and 6-His enable purification of their cognate fusion proteins on i mobiUzed glutathione, maltose, phenylarsine oxide, calmoduUn, and metal-chelate resins, respectively. FLAG, c-myc, and hemagglutinin (HA) enable immunoaffinity purification of fusion proteins using commerciaUy available monoclonal and polyclonal antibodies that specificaUy recognize these epitope tags. A fusion protein may also be engineered to contain a proteolytic cleavage site located between the OXRD encoding sequence and the heterologous protein sequence, so that OXRD may be cleaved away from the heterologous moiety foUowing purification. Methods for fusion protein expression and purification are discussed in Ausubel (1995, supra, ch. 10). A variety of commerciaUy available kits may also be used to faciUtate expression and purification of fusion proteins.

In a further embodiment of the invention, synthesis of radiolabeled OXRD may be achieved in vitro using the TNT rabbit reticulocyte lysate or wheat germ extract system (Promega). These systems couple transcription and translation of protein-coding sequences operably associated with the T7, T3, or SP6 promoters. Translation takes place in the presence of a radiolabeled amino acid precursor, for example, ³⁵S-methionine.

OXRD of the present invention or fragments thereof may be used to screen for compounds that specificaUy bind to OXRD. At least one and up to a pluraUty of test compounds may be screened for specific binding to OXRD. Examples of test compounds include antibodies, oUgonucleotides, proteins (e.g., receptors), or small molecules.

In one embodiment, the compound thus identified is closely related to the natural Ugand of OXRD, e.g., a Ugand or fragment thereof, a natural substrate, a structural or functional mimetic, or a natural binding partner. (See, e.g., CoUgan, J.E. et al. (1991) Current Protocols in Immunology 1(2): Chapter 5.) Similarly, the compound can be closely related to the natural receptor to which OXRD binds, or to at least a fragment of the receptor, e.g., the Ugand binding site. In either case, the compound can be rationaUy designed using known techniques. In one embodiment, screening for these compounds involves producing appropriate ceUs which express OXRD, either as a secreted protein or on the ceU membrane. Preferred cells include ceUs from mammals, yeast, Drosophila, or E. coU. CeUs expressing OXRD or ceU membrane fractions which contain OXRD are then contacted with a test compound and binding, stimulation, or inhibition of activity of either OXRD or the compound is analyzed.

An assay may simply test binding of a test compound to the polypeptide, wherein binding is detected by a fluorophore, radioisotope, enzyme conjugate, or other detectable label. For example, the assay may comprise the steps of combining at least one test compound with OXRD, either in solution or affixed to a soUd support, and detecting the binding of OXRD to the compound. Alternatively, the assay may detect or measure binding of a test compound in the presence of a labeled competitor. AdditionaUy, the assay may be carried out using cell-free preparations, chemical Ubraries, or natural product mixtures, and the test compound(s) may be free in solution or affixed to a soUd support.

OXRD of the present invention or fragments thereof may be used to screen for compounds that modulate the activity of OXRD. Such compounds may include agonists, antagonists, or partial or inverse agonists. In one embodiment, an assay is performed under conditions permissive for OXRD activity, wherein OXRD is combined with at least one test compound, and the activity of OXRD in the presence of a test compound is compared with the activity of OXRD in the absence of the test compound. A change in the activity of OXRD in the presence of the test compound is indicative of a compound that modulates the activity of OXRD. Alternatively, a test compound is combined with an in vitro or ceU-free system comprising OXRD under conditions suitable for OXRD activity, and the assay is performed. In either of these assays, a test compound which modulates the activity of OXRD may do so indirectly and need not come in direct contact with the test compound. At least one and up to a pluraUty of test compounds may be screened. En another embodiment, polynucleotides encoding OXRD or their mammaUan homologs may be "knocked out" in an animal model system using homologous recombination in embryonic stem (ES) ceUs. Such techniques are weU known in the art and are useful for the generation of animal models of human disease. (See, e.g., U.S. Patent No. 5,175,383 and U.S. Patent No. 5,767,337.) For example, mouse ES ceUs, such as the mouse 129/SvJ ceU Une, are derived from the early mouse embryo and grown in culture. The ES ceUs are transformed with a vector containing the gene of interest disrupted by a marker gene, e.g., the neomycin phosphotransferase gene (neo; Capecchi, M.R. (1989) Science 244:1288-1292). The vector integrates into the corresponding region of the host genome by homologous recombination. Alternatively, homologous recombination takes place using the Cre-loxP system to knockout a gene of interest in a tissue- or developmental stage-specific manner (Marth, J.D. (1996) CUn. Invest. 97:1999-2002; Wagner, K.U. et al. (1997) Nucleic Acids Res. 25:4323-4330). Transformed ES ceUs are identified and microinjected into mouse ceU blastocysts such as those from the C57BL/6 mouse strain. The blastocysts are surgicaUy transferred to pseudopregnant dams, and the resulting chimeric progeny are genotyped and bred to produce heterozygous or homozygous strains. Transgenic animals thus generated may be tested with potential therapeutic or toxic agents.

Polynucleotides encoding OXRD may also be manipulated in vitro in ES ceUs derived from human blastocysts. Human ES cells have the potential to differentiate into at least eight separate ceU Uneages including endoderm, mesoderm, and ectodermal cell types. These ceU Uneages differentiate into, for example, neural ceUs, hematopoietic Uneages, and cardiomyocytes (Thomson, J.A. et al (1998) Science 282:1145-1147).

Polynucleotides encoding OXRD can also be used to create "knockin" humanized animals (pigs) or transgenic animals (mice or rats) to model human disease. With knockin technology, a region of a polynucleotide encoding OXRD is injected into animal ES ceUs, and the injected sequence integrates into the animal ceU genome. Transformed cells are injected into blastulae, and the blastulae are implanted as described above. Transgenic progeny or inbred Unes are studied and treated with potential pharmaceutical agents to obtain information on treatment of a human disease. Alternatively, a mammal inbred to overexpress OXRD, e.g., by secreting OXRD in its milk, may also serve as a convenient source of that protein (Janne, J. et al. (1998) Biotechnol Annu. Rev. 4:55-74). THERAPEUTICS

Chemical and structural similarity, e.g., in the context of sequences and motifs, exists between regions of OXRD and oxidoreductases. In addition, examples of tissues expressing OXRD can be found in Table 6. Therefore, OXRD appears to play a role in ceU proUferative, neurological, metaboUc, and smooth muscle disorders. In the treatment of disorders associated with increased OXRD expression or activity, it is desirable to decrease the expression or activity of OXRD. In the treatment of disorders associated with decreased OXRD expression or activity, it is desirable to increase the expression or activity of OXRD.

Therefore, in one embodiment, OXRD or a fragment or derivative thereof may be administered to a subject to treat or prevent a disorder associated with decreased expression or activity of OXRD. Examples of such disorders include, but are not Umited to, a ceU proUferative disorder such as actinic keratosis, arteriosclerosis, atherosclerosis, bursitis, cirrhosis, hepatitis, mixed connective tissue disease (MCTD), myelofibrosis, paroxysmal nocturnal hemoglobinuria, polycythemia vera, psoriasis, primary thrombocythemia, and cancers including adenocarcinoma, leukemia, lymphoma, melanoma, myeloma, sarcoma, teratocarcinoma, and, in particular, cancers of the adrenal gland, bladder, bone, bone marrow, brain, breast, cervix, gall bladder, gangUa, gastrointestinal tract, heart, kidney, Uver, lung, muscle, ovary, pancreas, parathyroid, penis, prostate, saUvary glands, skin, spleen, testis, thymus, thyroid, and uterus; a neurological disorder such as epilepsy, ischemic cerebrovascular disease, stroke, cerebral neoplasms, Alzheimer's disease, Pick's disease, Huntington's disease, dementia, Parkinson's disease and other extrapyramidal disorders, amyotrophic lateral sclerosis and other motor neuron disorders, progressive neural muscular atrophy, retinitis pigmentosa, hereditary ataxias, multiple sclerosis and other demyeUnating diseases, bacterial and viral meningitis, brain abscess, subdural empyema, epidural abscess, suppurative intracranial thrombophlebitis, myeUtis and radicuUtis, viral central nervous system disease; prion diseases including kura, Creutzfeldt-Jakob disease, and Gerstmann-Straussler-Scheinker syndrome; fatal famiUal insomnia, nutritional and metaboUc diseases of the nervous system, neurofibromatosis, tuberous sclerosis, cerebeUoretinal hemangioblastomatosis, encephalotrigeminal syndrome, mental retardation and other developmental disorders of the central nervous system, cerebral palsy, neuroskeletal disorders, autonomic nervous system disorders, cranial nerve disorders, spinal cord diseases, muscular dystrophy and other neuromuscular disorders, peripheral nervous system disorders, dermatomyositis and polymyositis; inherited, metaboUc, endocrine, and toxic myopathies; myasthenia gravis, periodic paralysis; mental disorders including mood, anxiety, and schizophrenic disorders; seasonal affective disorder (SAD); akathesia, amnesia, catatonia, diabetic neuropathy, tardive dysWnesia, dystonias, paranoid psychoses, postherpetic neuralgia, Tourette's disorder, progressive supranuclear palsy, corticobasal degeneration, and familial frontotemporal dementia; a metaboUc disorder such as Sjoegren-Larsson syndrome (SLS), hyperproUnemia, type π, acute alcohol intoxication, adrenoleukodystrophy, Alport's syndrome, choroideremia, Duchenne and Becker muscular dystrophy, Down's syndrome, cystic fibrosis, chronic granulomatous disease, Gaucher' s disease, Huntington's chorea, Marfan's syndrome, muscular dystrophy, myotonic dystrophy, pycnodysostosis, Refsum's syndrome, retinoblastoma, sickle ceU anemia, thalassemia, Werner syndrome, von WiUebrand's disease, Wilms' tumor, Zellweger syndrome, peroxisomal acyl-CoA oxidase deficiency, peroxisomal thiolase deficiency, peroxisomal bifunctional protein deficiency, mitochondrial carnitine palmitoyl transferase and carnitine deficiency, mitochondrial very-long-chain acyl-CoA dehydrogenase deficiency, mitochondrial medium-chain acyl-CoA dehydrogenase deficiency, mitochondrial short- chain acyl-CoA dehydrogenase deficiency, mitochondrial electron transport flavoprotein and electron transport flavoprotein:ubiquinone oxidoreductase deficiency, mitochondrial trifunctional protein deficiency, and mitochondrial short-chain 3-hydroxyacyl-CoA dehydrogenase deficiency; and a smooth muscle disorder such as angina, anaphylactic shock, arrhythmias, asthma, cardiovascular shock, Gushing' s syndrome, hypertension, hypoglycemia, myocardial infarction, migraine, and pheochromocytoma, and myopathies including cardiomyopathy, encephalopathy, epilepsy, Kearns-Sayre syndrome, lactic acidosis, myoclonic disorder, and ophthalmoplegia, hyperammonemia, tiimethylaminuria (fish-odor syndrome), 3-hydroxydicarboxyUc aciduria, dicarboxyUc aciduria, xanthinuria, congenital Upoid adrenal hyperplasia (CLAH), albinism type HI, hyperinsulinism- hyperammonemia syndrome (HHS), glutaric acidemia type I (GA-I), famiUal recurrent myoglobinuria, insuUn resistance, hereditary thymine- uraciluria (famiUal pyrimidinemia), idiopathic sidereoblastic anemia (AISA), neonatal adrenoleukodystrophy, hypoxia, increased damage to tissues caused by trauma, radiation and ultraviolet exposure, Uver dysfunction, marked obesity, methemoglobinemia (HMl, HM2, and HM3), hypertrophic hirsutism with amenorrhea, and Hermansky-Pudlack syndrome, Reye's syndrome, hypoketotic hypoglycemia, isovaleric acidemia, and chronic hemolytic anemia.

In another embodiment, a vector capable of expressing OXRD or a fragment or derivative thereof may be administered to a subject to treat or prevent a disorder associated with decreased expression or activity of OXRD including, but not Umited to, those described above.

In a further embodiment, a composition comprising a substantiaUy purified OXRD in conjunction with a suitable pharmaceutical carrier may be administered to a subject to treat or prevent a disorder associated with decreased expression or activity of OXRD including, but not Umited to, those provided above.

In stiU another embodiment, an agonist which modulates the activity of OXRD may be administered to a subject to treat or prevent a disorder associated with decreased expression or activity of OXRD including, but not Umited to, those Usted above. In a further embodiment, an antagonist of OXRD may be administered to a subject to treat or prevent a disorder associated with increased expression or activity of OXRD. Examples of such disorders include, but are not Umited to, those ceU proUferative, neurological, metaboUc, and smooth muscle disorders described above. In one aspect, an antibody which specificaUy binds OXRD may be used directly as an antagonist or indirectly as a targeting or deUvery mechanism for bringing a pharmaceutical agent to ceUs or tissues which express OXRD.

In an additional embodiment, a vector expressing the complement of the polynucleotide encoding OXRD may be administered to a subject to treat or prevent a disorder associated with increased expression or activity of OXRD including, but not Umited to, those described above.

In other embodiments, any of the proteins, antagonists, antibodies, agonists, complementary sequences, or vectors of the invention may be administered in combination with other appropriate therapeutic agents. Selection of the appropriate agents for use in combination therapy may be made by one of ordinary skiU in the art, according to conventional pharmaceutical principles. The combination of therapeutic agents may act synergistically to effect the treatment or prevention of the various disorders described above. Using this approach, one may be able to achieve therapeutic efficacy with lower dosages of each agent, thus reducing the potential for adverse side effects.

An antagonist of OXRD may be produced using methods which are generaUy known in the art. In particular, purified OXRD may be used to produce antibodies or to screen Ubraries of pharmaceutical agents to identify those which specificaUy bind OXRD. Antibodies to OXRD may also be generated using methods that are well known in the art. Such antibodies may include, but are not Umited to, polyclonal, monoclonal, chimeric, and single chain antibodies, Fab fragments, and fragments produced by a Fab expression Ubrary. NeutraUzing antibodies (i.e., those which inhibit dimer formation) are generaUy preferred for therapeutic use.

For the production of antibodies, various hosts including goats, rabbits, rats, mice, humans, and others may be immunized by injection with OXRD or with any fragment or oUgopeptide thereof which has immunogenic properties. Depending on the host species, various adjuvants may be used to increase immunological response. Such adjuvants include, but are not Umited to, Freund's, mineral gels such as aluminum hydroxide, and surface active substances such as lysolecithin, pluronic polyols, polyanions, peptides, oil emulsions, KLH, and dinitiophenol Among adjuvants used in humans, BCG (bacilU Calmette-Guerin) and Corvnebacterium parvu are especiaUy preferable.

It is preferred that the oUgopeptides, peptides, or fragments used to induce antibodies to OXRD have an amino acid sequence consisting of at least about 5 amino acids, and generally wiU consist of at least about 10 amino acids. It is also preferable that these oUgopeptides, peptides, or fragments are identical to a portion of the amino acid sequence of the natural protein. Short stretches of OXRD amino acids may be fused with those of another protein, such as KLH, and antibodies to the chimeric molecule may be produced.

Monoclonal antibodies to OXRD may be prepared using any technique which provides for the production of antibody molecules by continuous cell Unes in culture. These include, but are not Umited to, the hybridoma technique, the human B-cell hybridoma technique, and the EB V-hybridoma technique. (See, e.g., Kohler, G. et al. (1975) Nature 256:495-497; Kozbor, D. et al. (1985) J. Immunol. Methods 81:31-42; Cote, R.J. et al. (1983) Proc. Natl. Acad. Sci. USA 80:2026-2030; and Cole, S.P. et al. (1984) Mol CeU Biol. 62:109-120.)

In addition, techniques developed for the production of "chimeric antibodies," such as the spUcing of mouse antibody genes to human antibody genes to obtain a molecule with appropriate antigen specificity and biological activity, can be used. (See, e.g., Morrison, S.L. et al. (1984) Proc. Natl. Acad. Sci. USA 81:6851-6855; Neuberger, M.S. et al. (1984) Nature 312:604-608; and Takeda, S. et al. (1985) Nature 314:452-454.) Alternatively, techniques described for the production of single chain antibodies may be adapted, using methods known in the ait, to produce OXRD-specific single chain antibodies. Antibodies with related specificity, but of distinct idiotypic composition, may be generated by chain shuffling from random combinatorial immunoglobuUn Ubraries. (See, e.g., Burton, D.R. (1991) Proc. Natl. Acad. Sci. USA 88:10134-10137.)

Antibodies may also be produced by inducing in vivo production in the lymphocyte population or by screening immunoglobuUn Ubraries or panels of highly specific binding reagents as disclosed in the Uterature. (See, e.g., Orlandi, R. et al (1989) Proc. Natl. Acad. Sci. USA 86:3833-3837; Winter, G. et al. (1991) Nature 349:293-299.)

Antibody fragments which contain specific binding sites for OXRD may also be generated. For example, such fragments include, but are not Umited to, F(ab')₂ fragments produced by pepsin digestion of the antibody molecule and Fab fragments generated by reducing the disulfide bridges of the F(ab')2 fragments. Alternatively, Fab expression Ubraries may be constructed to aUow rapid and easy identification of monoclonal Fab fragments with the desired specificity. (See, e.g., Huse, W.D. et al. (1989) Science 246:1275-1281.)

Various immunoassays may be used for screening to identify antibodies having the desired specificity. Numerous protocols for competitive binding or i munoradiometric assays using either polyclonal or monoclonal antibodies with estabUshed specificities are weU known in the art. Such immunoassays typicaUy involve the measurement of complex formation between OXRD and its specific antibody. A two-site, monoclonal-based immunoassay utiUzing monoclonal antibodies reactive to two non-interfering OXRD epitopes is generaUy used, but a competitive binding assay may also be employed (Pound, supra).

Various methods such as Scatchard analysis in conjunction with radioimmunoassay techniques may be used to assess the affinity of antibodies for OXRD. Affinity is expressed as an association constant, K., which is defined as the molar concentration of OXRD-antibody complex divided by the molar concentrations of free antigen and free antibody under equiUbrium conditions. The K, determined for a preparation of polyclonal antibodies, which are heterogeneous in their affinities for multiple OXRD epitopes, represents the average affinity, or avidity, of the antibodies for OXRD. The K_a determined for a preparation of monoclonal antibodies, which are monospecific for a particular OXRD epitope, represents a true measure of affinity. High-affinity antibody preparations with I ranging from about 10⁹ to 10¹² L/mole are preferred for use in immunoassays in which the OXRD-antibody complex must withstand rigorous manipulations. Low-affinity antibody preparations with K, ranging from about 10⁶ to 10⁷ L/mole are preferred for use in immunopurification and similar procedures which ultimately require dissociation of OXRD, preferably in active form, from-the antibody (Catty, D. (1988) Antibodies, Volume I: A Practical Approach, ERL Press, Washington DC; LiddeU, J.E. and A. Cryer (1991) A Practical Guide to Monoclonal Antibodies, John Wiley & Sons, New York NY).

The titer and avidity of polyclonal antibody preparations may be further evaluated to determine the quaUty and suitability of such preparations for certain downstream appUcations. For example, a polyclonal antibody preparation containing at least 1-2 mg specific antibody/ml, preferably 5-10 mg specific antibody/ml, is generaUy employed in procedures requiring precipitation of OXRD- antibody complexes. Procedures for evaluating antibody specificity, titer, and avidity, and guideUnes for antibody quaUty and usage in various appUcations, are generaUy available. (See, e.g., Catty, supra, and CoUgan et al. supra.)

In another embodiment of the invention, the polynucleotides encoding OXRD, or any fragment or complement thereof, may be used for therapeutic purposes. In one aspect, modifications of gene expression can be achieved by designing complementary sequences or antisense molecules (DNA, RNA, PNA, or modified oUgonucleotides) to the coding or regulatory regions of the gene encoding OXRD. Such technology is weU known in the art, and antisense oUgonucleotides or larger fragments can be designed from various locations along the coding or control regions of sequences encoding OXRD. (See, e.g., Agrawal, S., ed. (1996) Antisense Therapeutics, Humana Press Inc., TotawaNJ.)

In therapeutic use, any gene deUvery system suitable for introduction of the antisense sequences into appropriate target ceUs can be used. Antisense sequences can be deUvered intraceUularly in the form of an expression plasmid which, upon transcription, produces a sequence complementary to at least a portion of the cellular sequence encoding the target protein. (See, e.g., Slater, J.E. et al. (1998) J. AUergy CUn. Immunol. 102(3):469-475; and Scanlon, K.J. et al. (1995) 9(13):1288-1296.) Antisense sequences can also be introduced intraceUularly through the use of viral vectors, such as retroviras and adeno-associated viras vectors. (See, e.g., MiUer, AD. (1990) Blood 76:271; Ausubel, supra; Uckert, W. and W. Walther (1994) Pharmacol. Ther. 63(3):323-347.) Other gene deUvery mechanisms include Uposome-derived systems, artificial viral envelopes, and other systems known in the art. (See, e.g., Rossi, J.J. (1995) Br. Med. BuU. 51(l):217-225; Boado, RJ. et al. (1998) J. Pharm. Sci. 87(11):1308-1315; and Morris, M.C et al. (1997) Nucleic Acids Res. 25(14):2730-2736.)

En another embodiment of the invention, polynucleotides encoding OXRD may be used for somatic or germUne gene therapy. Gene therapy may be performed to (i) correct a genetic deficiency (e.g., in the cases of severe combined immunodeficiency (SCJD)-X1 disease characterized by X-Unked inheritance (Cavazzana-Calvo, M. et al. (2000) Science 288:669-672), severe combined immunodeficiency syndrome associated with an inherited adenosine deaminase (ADA) deficiency (Blaese, R.M. et al. (1995) Science 270:475-480; Bordignon, C et al. (1995) Science 270:470-475), cystic fibrosis (Zabner, J. et al. (1993) CeU 75:207-216; Crystal, R.G. et al. (1995) Hum. Gene Therapy 6:643-666; Crystal, R.G. et al (1995) Hum. Gene Therapy 6:667-703), thalassamias, famiUal hypercholesterolemia, and hemophilia resulting from Factor VEU or Factor IX deficiencies (Crystal, R.G. (1995) Science 270:404-410; Verma, I.M. and N. Somia (1997) Nature 389:239-242)), (n) express a conditionaUy lethal gene product (e.g., in the case of cancers which result from unregulated ceU proUferation), or (in) express a protein which affords protection against intraceUular parasites (e.g., against human retrovirases, such as human immunodeficiency viras (HJV) (Baltimore, D. (1988) Nature 335:395-396; Poeschla, E. et al. (1996) Proc. Natl. Acad. Sci. USA 93:11395-11399), hepatitis B or C virus (HBV, HCV); fungal parasites, such as Candida albicans and Paracoccidioides brasihensis; and protozoan parasites such as Plasmodium falciparum and Trypanosoma crazi). In the case where a genetic deficiency in OXRD expression or regulation causes disease, the expression of OXRD from an appropriate population of transduced ceUs may aUeviate the cUnical manifestations caused by the genetic deficiency.

In a further embodiment of the invention, diseases or disorders caused by deficiencies in OXRD are treated by constructing mammaUan expression vectors encoding OXRD and introducing these vectors by mechanical means into OXRD-deficient ceUs. Mechanical transfer technologies for use with ceUs in vivo or ex vitro include (i) direct DNA microinjection into individual ceUs, (U) baUistic gold particle deUvery, (Mi) Uposome-mediated transfection, (iv) receptor-mediated gene transfer, and (v) the use of DNA transposons (Morgan, R.A. and W.F. Anderson (1993) Annu. Rev. Biochem. 62:191-217; Ivies, Z. (1997) Cell 91:501-510; Boulay, J-L. and H. Recipon (1998) Curr. Opin. Biotechnol 9:445-450). Expression vectors that may be effective for the expression of OXRD include, but are not

Umited to, the PCDNA 3.1, EPITAG, PRCCMV2, PREP, PVAX, PCR2-TOPOTA vectors (Invitrogen, Carlsbad CA), PCMV-SCRJPT, PCMV-TAG, PEGSH/PERV (Stratagene, La JoUa CA), and PTET-OFF, PTET-ON, PTRE2, PTRE2-LUC, PTK-HYG (Clontech, Palo Alto CA). OXRD may be expressed using (i) a constitutively active promoter, (e.g., from cytomegalo virus (CMV), Rous sarcoma virus (RSV), SV40 virus, thymidine kinase (TK), or β-actin genes), (ii) an inducible promoter (e.g., the tetracycUne-regulated promoter (Gossen, M. and H. Bujard (1992) Proc. Natl. Acad. Sci. USA 89:5547-5551; Gossen, M. et al. (1995) Science 268:1766-1769; Rossi, F.M.V. and H.M. Blau (1998) Curr. Opin. Biotechnol 9:451-456), commerciaUy available in the T-REX plasmid (Invitrogen)); the ecdysone-inducible promoter (available in the plasmids PVGRXR and PIND; Invitrogen); the FK506/rapamycin inducible promoter; or the RU486/mifepristone inducible promoter (Rossi, F.M.V. and H.M. Blau, supra)), or (iii) a tissue-specific promoter or the native promoter of the endogenous gene encoding OXRD from a normal individual.

CommerciaUy available Uposome transformation kits (e.g., the PERFECT LEPED TRANSFECTION KIT, available from Invitrogen) aUow one with ordinary skill in the art to deUver polynucleotides to target ceUs in culture and require minimal effort to optimize experimental parameters. In the alternative, transformation is performed using the calcium phosphate method (Graham, F.L. and A.J. Eb (1973) Virology 52:456-467), or by electroporation (Neumann, E. et al. (1982) EMBO J. 1 :841-845). The introduction of DNA to primary ceUs requires modification of these standardized mammaUan transfection protocols. En another embodiment of the invention, diseases or disorders caused by genetic defects with respect to OXRD expression are treated by constructing a retroviras vector consisting of (i) the polynucleotide encoding OXRD under the control of an independent promoter or the retroviras long terminal repeat (LTR) promoter, (U) appropriate RNA packaging signals, and (Mi) a Rev-responsive element (RRE) along with additional retroviras ^'s-acting RNA sequences and coding sequences required for efficient vector propagation. Retroviras vectors (e.g., PFB and PFBNEO) are commerciaUy available (Stratagene) and are based on pubUshed data (Riviere, I. et al. (1995) Proc. Natl. Acad. Sci. USA 92:6733-6737), incorporated by reference herein. The vector is propagated in an appropriate vector producing cell Une (VPCL) that expresses an envelope gene with a tropism for receptors on the target ceUs or a promiscuous envelope protein such as VSVg (Armentano, D. et al. (1987) J. Virol. 61:1647-1650; Bender, M.A. et al. (1987) J. Virol. 61:1639-1646; Adam, M.A. and AD. MiUer (1988) J. Virol 62:3802-3806; DuU, T. et al. (1998) J. Virol. 72:8463-8471; Zufferey, R et al. (1998) J. Virol. 72:9873-9880). U.S. Patent No. 5,910,434 to Rigg ("Method for obtaining retroviras packaging ceU Unes producing high transducing efficiency retroviral supernatant") discloses a method for obtaining retroviras packaging ceU Unes and is hereby incorporated by reference. Propagation of retroviras vectors, transduction of a population of ceUs (e.g., CD4⁺ T-ceUs), and the return of transduced ceUs to a patient are procedures weU known to persons skiUed in the art of gene therapy and have been weU documented (Ranga, U. et al. (1997) J. Virol. 71:7020-7029; Bauer, G. et al. (1997) Blood 89:2259-2267; Bonyhadi, M.L. (1997) J. Virol. 71:4707-4716; Ranga, U. et al. (1998) Proc. Natl Acad. Sci. USA 95:1201-1206; Su, L. (1997) Blood 89:2283-2290).

In the alternative, an adenovirus-based gene therapy deUvery system is used to deUver polynucleotides encoding OXRD to ceUs which have one or more genetic abnormaUties with respect to the expression of OXRD. The construction and packaging of adenovirus-based vectors are weU known to those with ordinary skiU in the art. RepUcation defective adenovirus vectors have proven to be versatile for importing genes encoding immunoregulatory proteins into intact islets in the pancreas (Csete, M.E. et al. (1995) Transplantation 27:263-268). PotentiaUy useful adenoviral vectors are described in U.S. Patent No. 5,707,618 to Armentano ("Adenovirus vectors for gene therapy"), hereby incorporated by reference. For adenoviral vectors, see also Antinozzi, P.A. et al. (1999) Annu. Rev. Nutr. 19:511-544 and Verma, I.M. and N. Somia (1997) Nature 18:389:239-242, both incorporated by reference herein.

En another alternative, a herpes-based, gene therapy deUvery system is used to deUver polynucleotides encoding OXRD to target ceUs which have one or more genetic abnormaUties with respect to the expression of OXRD. The use of herpes simplex virus (HSV)-based vectors may be especiaUy valuable for introducing OXRD to ceUs of the central nervous system, for which HSV has a tropism. The construction and packaging of herpes-based vectors are weU known to those with ordinary skiU in the art. A repUcation-competent herpes simplex virus (HSV) type 1 -based vector has been used to deUver a reporter gene to the eyes of primates (Liu, X. et al. (1999) Exp. Eye Res. 169:385-395). The construction of a HSV-1 virus vector has also been disclosed in detail in U.S. Patent No. 5,804,413 to DeLuca ("Herpes simplex viras strains for gene transfer"), which is hereby incoiporated by reference. U.S. Patent No. 5,804,413 teaches the use of recombinant HSV d92 which consists of a genome containing at least one exogenous gene to be transferred to a ceU under the control of the appropriate promoter for purposes including human gene therapy. Also taught by this patent are the construction and use of recombinant HSV strains deleted for ICP4, ICP27 and ICP22. For HSV vectors, see also Goins, W.F. et al. (1999) J. Virol. 73:519-532 and Xu, H. et al. (1994) Dev. Biol. 163:152-161, hereby incorporated by reference. The manipulation of cloned herpesviras sequences, the generation of recombinant viras foUowing the transfection of multiple plasmids containing different segments of the large herpesviras genomes, the growth and propagation of herpesviras, and the infection of ceUs with herpesviras are techniques weU known to those of ordinary skiU in the art.

In another alternative, an alphaviras (positive, single-stranded RNA virus) vector is used to deUver polynucleotides encoding OXRD to target ceUs. The biology of the prototypic alphaviras, Semliki Forest Virus (SFV), has been studied extensively and gene transfer vectors have been based on the SFV genome (Garoff, H. and K.-J. Li (1998) Curr. Opin. Biotechnol. 9:464-469). During alphaviras RNA repUcation, a subgenomic RNA is generated that normaUy encodes the viral capsid proteins. This subgenomic RNA repUcates to higher levels than the fuU length genomic RNA, resulting in the overproduction of capsid proteins relative to the viral proteins with enzymatic activity (e.g., protease and polymerase). Similarly, inserting the coding sequence for OXRD into the alphaviras genome in place of the capsid-coding region results in the production of a large number of OXRD-coding RNAs and the synthesis of high levels of OXRD in vector transduced ceUs. While alphaviras infection is typicaUy associated with ceU lysis within a few days, the abiUty to estabUsh a persistent infection in hamster normal kidney ceUs (BHK-21) with a variant of Sindbis viras (SEN) indicates that the lytic repUcation of alphavirases can be altered to suit the needs of the gene therapy appUcation (Dryga, S.A. et al. (1997) Virology 228:74-83). The wide host range of alphavirases wiU aUow the introduction of OXRD into a variety of ceU types. The specific transduction of a subset of ceUs in a population may require the sorting of ceUs prior to transduction. The methods of manipulating infectious cDNA clones of alphavirases, performing alphaviras cDNA and RNA transfections, and performing alphaviras infections, are weU known to those with ordinary skiU in the art.

OUgonucleotides derived from the transcription initiation site, e.g., between about positions -10 and +10 from the start site, may also be employed to inhibit gene expression. Similarly, inhibition can be achieved using triple heUx base-pairing methodology. Triple heUx pairing is useful because it causes inhibition of the abiUty of the double heUx to open sufficiently for the binding of polymerases, transcription factors, or regulatory molecules. Recent therapeutic advances using triplex DNA have been described in the Uterature. (See, e.g., Gee, J.E. et al. (1994) in Huber, B.E. and B.I. Carr, Molecular and Emmunologic Approaches, Futura PubUshing, Mt. Kisco NY, pp. 163-177.) A complementary sequence or antisense molecule may also be designed to block translation of mRNA by preventing the transcript from binding to ribosomes.

Ribozymes, enzymatic RNA molecules, may also be used to catalyze the specific cleavage of RNA. The mechanism of ribozyme action involves sequence-specific hybridization of the ribozyme molecule to complementary target RNA, foUowed by endonucleolytic cleavage. For example, engineered hammerhead motif ribozyme molecules may specificaUy and efficiently catalyze endonucleolytic cleavage of sequences encoding OXRD.

Specific ribozyme cleavage sites within any potential RNA target are initiaUy identified by scanning the target molecule for ribozyme cleavage sites, including the foUowing sequences: GUA, GUU, and GUC Once identified, short RNA sequences of between 15 and 20 ribonucleotides, corresponding to the region of the target gene containing the cleavage site, may be evaluated for secondary structural features which may render the oUgonucleotide inoperable. The suitabiUty of candidate targets may also be evaluated by testing accessibiUty to hybridization with complementary oUgonucleotides using ribonuclease protection assays. Complementary ribonucleic acid molecules and ribozymes of the invention may be prepared by any method known in the art for the synthesis of nucleic acid molecules. These include techniques for chemically synthesizing oUgonucleotides such as soUd phase phosphoramidite chemical synthesis. Alternatively, RNA molecules may be generated by in vitro and in vivo transcription of DNA sequences encoding OXRD. Such DNA sequences may be incorporated into a wide variety of vectors with suitable RNA polymerase promoters such as T7 or SP6. Alternatively, these cDNA constracts that synthesize complementary RNA, constimtively or inducibly, can be introduced into ceU Unes, ceUs, or tissues.

RNA molecules may be modified to increase intraceUular stabiUty and half-Ufe. Possible modifications include, but are not Umited to, the addition of flanking sequences at the 5' and/or 3' ends of the molecule, or the use of phosphorothioate or 2' O-methyl rather than phosphodiesterase Unkages within the backbone of the molecule. This concept is inherent in the production of PNAs and can be extended in aU of these molecules by the inclusion of nontraditional bases such as inosine, queosine, and wybutosine, as weU as acetyl-, methyl-, thio-, and similarly modified forms of adenine, cytidine, guanine, thymine, and uridine which are not as easily recognized by endogenous endonucleases.

An additional embodiment of the invention encompasses a method for screening for a compound which is effective in altering expression of a polynucleotide encoding OXRD. Compounds which may be effective in altering expression of a specific polynucleotide may include, but are not Umited to, oUgonucleotides, antisense oUgonucleotides, triple heUx-forming oUgonucleotides, transcription factors and other polypeptide transcriptional regulators, and non-macromolecular chemical entities which are capable of interacting with specific polynucleotide sequences. Effective compounds may alter polynucleotide expression by acting as either inhibitors or promoters of polynucleotide expression. Thus, in the treatment of disorders associated with increased OXRD expression or activity, a compound which specificaUy inhibits expression of the polynucleotide encoding OXRD may be therapeuticaUy useful, and in the treatment of disorders associated with decreased OXRD expression or activity, a compound which specificaUy promotes expression of the polynucleotide encoding OXRD may be therapeuticaUy useful.

At least one, and up to a pluraUty, of test compounds may be screened for effectiveness in altering expression of a specific polynucleotide. A test compound may be obtained by any method commonly known in the art, including chemical modification of a compound known to be effective in altering polynucleotide expression; selection from an existing, commerciaUy-available or proprietary Ubrary of naturally-occurring or non-natural chemical compounds; rational design of a compound based on chemical and/or structural properties of the target polynucleotide; and selection from a Ubrary of chemical compounds created combinatoriaUy or randomly. A sample comprising a polynucleotide encoding OXRD is exposed to at least one test compound thus obtained. The sample may comprise, for example, an intact or permeabiUzed cell, or an in vitro ceU-free or reconstituted biochemical system. Alterations in the expression of a polynucleotide encoding OXRD are assayed by any method commonly known in the art. TypicaUy, the expression of a specific nucleotide is detected by hybridization with a probe having a nucleotide sequence complementary to the sequence of the polynucleotide encoding OXRD. The amount of hybridization may be quantified, thus forming the basis for a comparison of the expression of the polynucleotide both with and without exposure to one or more test compounds. Detection of a change in the expression of a polynucleotide exposed to a test compound indicates that the test compound is effective in altering the expression of the polynucleotide. A screen for a compound effective in altering expression of a specific polynucleotide can be carried out, for example, using a Schizosaccharomvces pombe gene expression system (Atkins, D. et al. (1999) U.S. Patent No. 5,932,435; Arndt, G.M. et al. (2000) Nucleic Acids Res. 28:E15) or a human ceU Une such as HeLa ceU (Clarke, M.L. et al. (2000) Biochem. Biophys. Res. Commun. 268:8-13). A particular embodiment of the present invention involves screening a combinatorial Ubrary of oUgonucleotides (such as deoxyribonucleotides, ribonucleotides, peptide nucleic acids, and modified oUgonucleotides) for antisense activity against a specific polynucleotide sequence (Bruice, T.W. et al. (1997) U.S. Patent No. 5,686,242; Brake, T.W. et al. (2000) U.S. Patent No. 6,022,691).

Many methods for introducing vectors into ceUs or tissues are available and equaUy suitable for use in vivo, in vitro, and ex vivo. For ex vivo therapy, vectors may be introduced into stem ceUs taken from the patient and clonaUy propagated for autologous transplant back into that same patient. DeUvery by transfection, by Uposome injections, or by polycationic amino polymers may be achieved using methods which are weU known in the art. (See, e.g., Goldman, C.K. et al. (1997) Nat. Biotechnol. 15:462-466.)

Any of the therapeutic methods described above may be appUed to any subject in need of such therapy, including, for example, mammals such as humans, dogs, cats, cows, horses, rabbits, and monkeys. An additional embodiment of the invention relates to the administration of a composition which generaUy comprises an active ingredient formulated with a pharmaceuticaUy acceptable excipient. Excipients may include, for example, sugars, starches, ceUuloses, gums, and proteins. Various formulations are commonly known and are thoroughly discussed in the latest edition of Remington's Pharmaceutical Sciences (Maack PubUshing, Easton PA). Such compositions may consist of OXRD, antibodies to OXRD, and mimetics, agonists, antagonists, or inhibitors of OXRD. The compositions utiUzed in this invention may be administered by any number of routes including, but not Umited to, oral, intravenous, intramuscular, intra-arterial, intrameduUary, intrathecal, intraventricular, pulmonary, transdermal, subcutaneous, intraperitoneal, intranasal, enteral, topical, subUngual, or rectal means. Compositions for pulmonary administration may be prepared in Uquid or dry powder form.

These compositions are generaUy aerosoUzed immediately prior to inhalation by the patient. In the case of smaU molecules (e.g. traditional low molecular weight organic drugs), aerosol deUvery of fast- acting formulations is weU-known in the art. In the case of macromolecules (e.g. larger peptides and proteins), recent developments in the field of pulmonary deUvery via the alveolar region of the lung have enabled the practical deUvery of drags such as insuUn to blood circulation (see, e.g., Patton, J.S. et al, U.S. Patent No. 5,997,848). Pulmonary deUvery has the advantage of administration without needle injection, and obviates the need for potentiaUy toxic penetration enhancers.

Compositions suitable for use in the invention include compositions wherein the active ingredients are contained in an effective amount to achieve the intended purpose. The determination of an effective dose is weU within the capabiUty of those skilled in the art.

SpeciaUzed forms of compositions may be prepared for direct intraceUular deUvery of macromolecules comprising OXRD or fragments thereof. For example, Uposome preparations containing a ceU-impermeable macromolecule may promote ceU fusion and intracellular deUvery of the macromolecule. Alternatively, OXRD or a fragment thereof may be joined to a short cationic N- terminal portion from the HIV Tat-1 protein. Fusion proteins thus generated have been found to transduce into the ceUs of aU tissues, including the brain, in a mouse model system (Schwarze, S.R. et al. (1999) Science 285:1569-1572). For any compound, the therapeuticaUy effective dose can be estimated initiaUy either in ceU culture assays, e.g., of neoplastic ceUs, or in animal models such as mice, rats, rabbits, dogs, monkeys, or pigs. An animal model may also be used to determine the appropriate concentration range and route of administration. Such information can then be used to determine useful doses and routes for administration in humans. A therapeutically effective dose refers to that amount of active ingredient, for example

OXRD or fragments thereof, antibodies of OXRD, and agonists, antagonists or inhibitors of OXRD, which ameUorates the symptoms or condition. Therapeutic efficacy and toxicity may be determined by standard pharmaceutical procedures in ceU cultures or with experimental animals, such as by calculating the ED₅₀ (the dose therapeutically effective in 50% of the population) or LD₅₀ (the dose lethal to 50% of the population) statistics. The dose ratio of toxic to therapeutic effects is the therapeutic index, which can be expressed as the LD₅₀/ED₅₀ ratio. Compositions which exhibit large therapeutic indices are preferred. The data obtained from cell culture assays and animal studies are used to formulate a range of dosage for human use. The dosage contained in such compositions is preferably within a range of circulating concentrations that includes the ED₅₀ with Uttle or no toxicity. The dosage varies within this range depending upon the dosage form employed, the sensitivity of the patient, and the route of administration.

The exact dosage wiU be determined by the practitioner, in Ught of factors related to the subject requiring treatment. Dosage and administration are adjusted to provide sufficient levels of the active moiety or to maintain the desired effect. Factors which may be taken into account include the severity of the disease state, the general health of the subject, the age, weight, and gender of the subject, time and frequency of administration, drug combination(s), reaction sensitivities, and response to therapy. Long-acting compositions may be administered every 3 to 4 days, every week, or biweekly depending on the half-Ufe and clearance rate of the particular formulation. Normal dosage amounts may vary from about 0.1 μg to 100,000 μg, up to a total dose of about 1 gram, depending upon the route of administration. Guidance as to particular dosages and methods of deUvery is provided in the Uterature and generaUy available to practitioners in the art. Those skilled in the art wiU employ different formulations for nucleotides than for proteins or their inhibitors. Similarly, deUvery of polynucleotides or polypeptides wiU be specific to particular ceUs, conditions, locations, etc. DIAGNOSTICS

En another embodiment, antibodies which specificaUy bind OXRD may be used for the diagnosis of disorders characterized by expression of OXRD, or in assays to monitor patients being treated with OXRD or agonists, antagonists, or inhibitors of OXRD. Antibodies useful for diagnostic purposes may be prepared in the same manner as described above for therapeutics. Diagnostic assays for OXRD include methods which utilize the antibody and a label to detect OXRD in human body fluids or in extracts of cells or tissues. The antibodies may be used with or without modification, and may be labeled by covalent or non-covalent attachment of a reporter molecule. A wide variety of reporter molecules, several of which are described above, are known in the art and may be used.

A variety of protocols for measuring OXRD, including ELISAs, RIAs, and FACS, are known in the art and provide a basis for diagnosing altered or abnormal levels of OXRD expression. Normal or standard values for OXRD expression are estabUshed by combining body fluids or ceU extracts taken from normal mammaUan subjects, for example, human subjects, with antibodies to OXRD under conditions suitable for complex formation. The amount of standard complex formation may be quantitated by various methods, such as photometric means. Quantities of OXRD expressed in subject, control and disease samples from biopsied tissues are compared with the standard values. Deviation between standard and subject values estabUshes the parameters for diagnosing disease. In another embodiment of the invention, the polynucleotides encoding OXRD may be used for diagnostic purposes. The polynucleotides which may be used include oUgonucleotide sequences, complementary RNA and DNA molecules, and PNAs. The polynucleotides may be used to detect and quantify gene expression in biopsied tissues in which expression of OXRD may be correlated with disease. The diagnostic assay may be used to determine absence, presence, and excess expression of OXRD, and to monitor regulation of OXRD levels during therapeutic intervention. In one aspect, hybridization with PCR probes which are capable of detecting polynucleotide sequences, including genomic sequences, encoding OXRD or closely related molecules may be used to identify nucleic acid sequences which encode OXRD. The specificity of the probe, whether it is made from a highly specific region, e.g., the 5' regulatory region, or from a less specific region, e.g., a conserved motif, and the stringency of the hybridization or ampUfication wiU determine whether the probe identifies only naturaUy occurring sequences encoding OXRD, aUeUc variants, or related sequences.

Probes may also be used for the detection of related sequences, and may have at least 50% sequence identity to any of the OXRD encoding sequences. The hybridization probes of the subject invention may be DNA or RNA and may be derived from the sequence of SEQ JD NO:4-6 or from genomic sequences including promoters, enhancers, and introns of the OXRD gene.

Means for producing specific hybridization probes for DNAs encoding OXRD include the cloning of polynucleotide sequences encoding OXRD or OXRD derivatives into vectors for the production of mRNA probes. Such vectors are known in the art, are commercially available, and may be used to synthesize RNA probes in vitro by means of the addition of the appropriate RNA polymerases and the appropriate labeled nucleotides. Hybridization probes may be labeled by a variety of reporter groups, for example, by radionucUdes such as ³²P or ³⁵S, or by enzymatic labels, such as alkaUne phosphatase coupled to the probe via avidin/biotin coupUng systems, and the Uke. Polynucleotide sequences encoding OXRD may be used for the diagnosis of disorders associated with expression of OXRD. Examples of such disorders include, but are not Umited to, a cell proUferative disorder such as actinic keratosis, arteriosclerosis, atherosclerosis, bursitis, cirrhosis, hepatitis, mixed connective tissue disease (MCTD), myelofibrosis, paroxysmal nocturnal hemoglobinuria, polycythemia vera, psoriasis, primary thrombocythemia, and cancers including adenocarcinoma, leukemia, lymphoma, melanoma, myeloma, sarcoma, teratocarcinoma, and, in particular, cancers of the adrenal gland, bladder, bone, bone marrow, brain, breast, cervix, gaU bladder, gangUa, gastrointestinal tract, heart, kidney, Uver, lung, muscle, ovary, pancreas, parathyroid, penis, prostate, saUvary glands, skin, spleen, testis, thymus, thyroid, and uteras; a neurological disorder such as epilepsy, ischemic cerebrovascular disease, stroke, cerebral neoplasms, Alzheimer's disease, Pick's disease, Huntington's disease, dementia, Parkinson's disease and other extrapyramidal disorders, amyotrophic lateral sclerosis and other motor neuron disorders, progressive neural muscular atrophy, retinitis pigmentosa, hereditary ataxias, multiple sclerosis and other demyeUnating diseases, bacterial and viral meningitis, brain abscess, subdural empyema, epidural abscess, suppurative intracranial thrombophlebitis, myeUtis and radicuUtis, viral central nervous system disease; prion diseases including kuru, Creutzfeldt-Jakob disease, and Gerstmann-Straussler-Scheinker syndrome; fatal famiUal insomnia, nutritional and metaboUc diseases of the nervous system, nemofibromatosis, tuberous sclerosis, cerebeUoretinal hemangioblastomatosis, encephalotrigeminal syndrome, mental retardation and other developmental disorders of the central nervous system, cerebral palsy, neuroskeletal disorders, autonomic nervous system disorders, cranial nerve disorders, spinal cord diseases, muscular dystrophy and other neuromuscular disorders, peripheral nervous system disorders, dermatomyositis and polymyositis; inherited, metaboUc, endocrine, and toxic myopathies; myasthenia gravis, periodic paralysis; mental disorders including mood, anxiety, and schizophrenic disorders; seasonal affective disorder (SAD); akathesia, amnesia, catatonia, diabetic neuropathy, tardive dyskinesia, dystonias, paranoid psychoses, postherpetic neuralgia, Tourette's disorder, progressive supranuclear palsy, corticobasal degeneration, and famiUal frontotemporal dementia; a metaboUc disorder such as Sjoegren-Larsson syndrome (SLS), hyperproUnemia, type Et, acute alcohol intoxication, adrenoleukodystrophy, Alport's syndrome, choroideremia, Duchenne and Becker muscular dystrophy, Down's syndrome, cystic fibrosis, chronic granulomatous disease, Gaucher' s disease, Huntington's chorea, Marian's syndrome, muscular dystrophy, myotonic dystrophy, pycnodysostosis, Refsum's syndrome, retinoblastoma, sickle cell anemia, thalassemia, Werner syndrome, von WiUebrand's disease, Wilms' tumor, ZeUweger syndrome, peroxisomal acyl-CoA oxidase deficiency, peroxisomal thiolase deficiency, peroxisomal bifunctional protein deficiency, mitochondrial carnitine paknitoyl transferase and carnitine deficiency, mitochondrial very-long-chain acyl-CoA dehydrogenase deficiency, mitochondrial medium-chain acyl-CoA dehydrogenase deficiency, mitochondrial short-chain acyl-CoA dehydrogenase deficiency, mitochondrial electron transport flavoprotein and electron transport flavoprotein:ubiquinone oxidoreductase deficiency, mitochondrial trifunctional protein deficiency, and mitochondrial short-chain 3-hydroxyacyl-CoA dehydrogenase deficiency; and a smooth muscle disorder such as angina, anaphylactic shock, arrhythmias, asthma, cardiovascular shock, Cushing's syndrome, hypertension, hypoglycemia, myocardial infarction, migraine, and pheochromocytoma, and myopathies including cardiomyopathy, encephalopathy, epilepsy, Kearns-Sayre syndrome, lactic acidosis, myoclonic disorder, and ophthalmoplegia, hyperammonemia, tximethylaminuria (fish-odor syndrome), 3-hydroxydicarboxyUc aciduria, dicarboxyUc aciduria, xanthinuria, congenital Upoid adrenal hyperplasia (CLAH), albinism type HI, hyperinsuUnism-hyperammonemia syndrome (HHS), glutaric acidemia type I (GA-I), famiUal recurrent myoglobinuria, insuUn resistance, hereditary thymine- uraciluria (famiUal pyrimidinemia), idiopathic sidereoblastic anemia (AISA), neonatal adrenoleukodystrophy, hypoxia, increased damage to tissues caused by trauma, radiation and ultraviolet exposure, Uver dysfunction, marked obesity, methemoglobinemia (HM1, HM2, and HM3), hypertrophic hirsutism with amenorrhea, and

Hermansky-Pudlack syndrome, Reye's syndrome, hypoketotic hypoglycemia, isovaleric acidemia, and chronic hemolytic anemia. The polynucleotide sequences encoding OXRD may be used in Southern or northern analysis, dot blot, or other membrane-based technologies; in PCR technologies; in dipstick, pin, and multiformat ELISA-Uke assays; and in microarrays utiUzing fluids or tissues from patients to detect altered OXRD expression. Such quaUtative or quantitative methods are weU known in the art.

In a particular aspect, the nucleotide sequences encoding OXRD may be useful in assays that detect the presence of associated disorders, particularly those mentioned above. The nucleotide sequences encoding OXRD may be labeled by standard methods and added to a fluid or tissue sample from a patient under conditions suitable for the formation of hybridization complexes. After a suitable incubation period, the sample is washed and the signal is quantified and compared with a standard value. If the amount of signal in the patient sample is significantly altered in comparison to a control sample then the presence of altered levels ofnucleoti.de sequences encoding OXRD in the sample indicates the presence of the associated disorder. Such assays may also be used to evaluate the efficacy of a particular therapeutic treatment regimen in animal studies, in cUnical trials, or to monitor the tieatment of an individual patient.

In order to provide a basis for the diagnosis of a disorder associated with expression of OXRD, a normal or standard profile for expression is estabUshed. This may be accompUshed by combining body fluids or ceU extracts taken from normal subjects, either animal or human, with a sequence, or a fragment thereof, encoding OXRD, under conditions suitable for hybridization or ampUfication. Standard hybridization may be quantified by comparing the values obtained from normal subjects with values from an experiment in which a known amount of a substantially purified polynucleotide is used. Standard values obtained in this manner may be compared with values obtained from samples from patients who are symptomatic for a disorder. Deviation from standard values is used to estabUsh the presence of a disorder.

Once the presence of a disorder is estabUshed and a treatment protocol is initiated, hybridization assays may be repeated on a regular basis to determine if the level of expression in the patient begins to approximate that which is observed in the normal subject. The results obtained from successive assays may be used to show the efficacy of treatment over a period ranging from several days to months.

With respect to cancer, the presence of an abnormal amount of transcript (either under- or overexpressed) in biopsied tissue from an individual may indicate a predisposition for the development of the disease, or may provide a means for detecting the disease prior to the appearance of actual cUnical symptoms. A more definitive diagnosis of this type may aUow health professionals to employ preventative measures or aggressive treatment earUer thereby preventing the development or further progression of the cancer.

Additional diagnostic uses for oUgonucleotides designed from the sequences encoding OXRD may involve the use of PCR. These oUgomers may be chemicaUy synthesized, generated enzymaticaUy, or produced in vitro. OUgomers wiU preferably contain a fragment of a polynucleotide encoding OXRD, or a fragment of a polynucleotide complementary to the polynucleotide encoding OXRD, and will be employed under optimized conditions for identification of a specific gene or condition. OUgomers may also be employed under less stringent conditions for detection or quantification of closely related DNA or RNA sequences.

In a particular aspect, oUgonucleotide primers derived from the polynucleotide sequences encoding OXRD may be used to detect single nucleotide polymorphisms (SNPs). SNPs are substitutions, insertions and deletions that are a frequent cause of inherited or acquired genetic disease in humans. Methods of SNP detection include, but are not Umited to, single-stranded conformation polymorphism (SSCP) and fluorescent SSCP (fSSCP) methods. In SSCP, oUgonucleotide primers derived from the polynucleotide sequences encoding OXRD are used to ampUfy DNA using the polymerase chain reaction (PCR). The DNA may be derived, for example, from diseased or normal tissue, biopsy samples, bodily fluids, and the Uke. SNPs in the DNA cause differences in the secondary and tertiary structures of PCR products in single-stranded form, and these differences are detectable using gel electrophoresis in non-denaturing gels. In fSCCP, the oUgonucleotide primers are fluorescently labeled, which allows detection of the ampUmers in high- throughput equipment such as DNA sequencing machines. AdditionaUy, sequence database analysis methods, termed in siUco SNP (isSNP), are capable of identifying polymorphisms by comparing the sequence of individual overlapping DNA fragments which assemble into a common consensus sequence. These computer-based methods filter out sequence variations due to laboratory preparation of DNA and sequencing errors using statistical models and automated analyses of DNA sequence chromatograms. In the alternative, SNPs may be detected and characterized by mass spectrometry using, for example, the high throughput MASSARRAY system (Sequenom, Inc., San Diego CA).

Methods which may also be used to quantify the expression of OXRD include radiolabeUng or biotinylating nucleotides, coampUfication of a control nucleic acid, and interpolating results from standard curves. (See, e.g., Melby, P.C et al (1993) J. Immunol. Methods 159:235-244; Duplaa, C et al. (1993) Anal Biochem. 212:229-236.) The speed of quantitation of multiple samples may be accelerated by running the assay in a high-throughput format where the oUgomer or polynucleotide of interest is presented in various dilutions and a spectrophotometiic or colorimetric response gives rapid quantitation.

En further embodiments, oUgonucleotides or longer fragments derived from any of the polynucleotide sequences described herein may be used as elements on a microarray. The microarray can be used in transcript imaging techniques which monitor the relative expression levels of large numbers of genes simultaneously as described below. The microarray may also be used to identify genetic variants, mutations, and polymorphisms. This information may be used to determine gene function, to understand the genetic basis of a disorder, to diagnose a disorder, to monitor progression regression of disease as a function of gene expression, and to develop and monitor the activities of therapeutic agents in the treatment of disease. In particular, this information may be used to develop a pharmacogenomic profile of a patient in order to select the most appropriate and effective treatment regimen for that patient. For example, therapeutic agents which are highly effective and display the fewest side effects may be selected for a patient based on his/her pharmacogenomic profile.

In another embodiment, OXRD, fragments of OXRD, or antibodies specific for OXRD may be used as elements on a microarray. The microarray may be used to monitor or measure protein- protein interactions, drag-target interactions, and gene expression profiles, as described above. A particular embodiment relates to the use of the polynucleotides of the present invention to generate a transcript image of a tissue or ceU type. A transcript image represents the global pattern of gene expression by a particular tissue or cell type. Global gene expression patterns are analyzed by quantifying the number of expressed genes and their relative abundance under given conditions and at a given time. (See Seilhamer et al, "Comparative Gene Transcript Analysis," U.S. Patent No. 5,840,484, expressly incorporated by reference herein.) Thus a transcript image may be generated by hybridizing the polynucleotides of the present invention or their complements to the totaUty of transcripts or reverse transcripts of a particular tissue or ceU type. In one embodiment, the hybridization takes place in high-throughput format, wherein the polynucleotides of the present invention or their complements comprise a subset of a pluraUty of elements on a microarray. The resultant transcript image would provide a profile of gene activity.

Transcript images may be generated using transcripts isolated from tissues, ceU Unes, biopsies, or other biological samples. The transcript image may thus reflect gene expression in vivo, as in the case of a tissue or biopsy sample, or in vitro, as in the case of a ceU Une.

Transcript images which profile the expression of the polynucleotides of the present invention may also be used in conjunction with in vitro model systems and precUnical evaluation of pharmaceuticals, as weU as toxicological testing of industrial and naturaUy-occurring environmental compounds. AU compounds induce characteristic gene expression patterns, frequently termed molecular fingerprints or toxicant signatures, which are indicative of mechanisms of action and toxicity (Nuwaysir, E.F. et al. (1999) Mol. Carcinog. 24:153-159; Steiner, S. and N.L. Anderson (2000) Toxicol Lett. 112-113:467-471, expressly incorporated by reference herein). If atest compound has a signature similar to that of a compound with known toxicity, it is Ukely to share those toxic properties. These fingerprints or signatures are most useful and refined when they contain expression information from a large number of genes and gene famiUes. IdeaUy, a genome- wide measurement of expression provides the highest quaUty signature. Even genes whose expression is not altered by any tested compounds are important as weU, as the levels of expression of these genes are used to normaUze the rest of the expression data. The normaUzation procedure is useful for comparison of expression data after treatment with different compounds. While the assignment of gene function to elements of a toxicant signature aids in interpretation of toxicity mechanisms, knowledge of gene function is not necessary for the statistical matching of signatures which leads to prediction of toxicity. (See, for example, Press Release 00-02 from the National Institute of Environmental Health Sciences, released February 29, 2000, available at htφ.7/www.niehs.nih.gov/oc/news/toxchip.htm.) Therefore, it is important and desirable in toxicological screening using toxicant signatures to include aU expressed gene sequences.

In one embodiment, the toxicity of a test compound is assessed by treating a biological sample containing nucleic acids with the test compound. Nucleic acids that are expressed in the treated biological sample are hybridized with one or more probes specific to the polynucleotides of the present invention, so that transcript levels corresponding to the polynucleotides of the present invention may be quantified. The transcript levels in the treated biological sample are compared with levels in an untreated biological sample. Differences in the transcript levels between the two samples are indicative of a toxic response caused by the test compound in the treated sample.

Another particular embodiment relates to the use of the polypeptide sequences of the present invention to analyze the proteome of a tissue or ceU type. The term proteome refers to the global pattern of protein expression in a particular tissue or ceU type. Each protein component of a proteome can be subjected individuaUy to further analysis. Proteome expression patterns, or profiles, are analyzed by quantifying the number of expressed proteins and their relative abundance under given conditions and at a given time. A profile of a cell's proteome may thus be generated by separating and analyzing the polypeptides of a particular tissue or cell type. In one embodiment, the separation is achieved using two-dimensional gel electrophoresis, in which proteins from a sample are separated by isoelectric focusing in the first dimension, and then according to molecular weight by sodium dodecyl sulfate slab gel electrophoresis in the second dimension (Steiner and Anderson, supra). The proteins are visuaUzed in the gel as discrete and uniquely positioned spots, typicaUy by staining the gel with an agent such as Coomassie Blue or silver or fluorescent stains. The optical density of each protein spot is generaUy proportional to the level of the protein in the sample. The optical densities of equivalently positioned protein spots from different samples, for example, from biological samples either treated or untreated with a test compound or therapeutic agent, are compared to identify any changes in protein spot density related to the treatment. The proteins in the spots are partiaUy sequenced using, for example, standard methods employing chemical or enzymatic cleavage foUowed by mass spectrometry. The identity of the protein in a spot may be determined by comparing its partial sequence, preferably of at least 5 contiguous amino acid residues, to the polypeptide sequences of the present invention. In some cases, further sequence data may be obtained for definitive protein identification.

A proteomic profile may also be generated using antibodies specific for OXRD to quantify the levels of OXRD expression. In one embodiment, the antibodies are used as elements on a microarray, and protein expression levels are quantified by exposing the microarray to the sample and detecting the levels of protein bound to each array element (Lueking, A. et al. (1999) Anal. Biochem. 270:103-111 ; Mendoze, L.G. et al. (1999) Biotechniques 27:778-788). Detection may be performed by a variety of methods known in the art, for example, by reacting the proteins in the sample with a thiol- or amino-reactive fluorescent compound and detecting the amount of fluorescence bound at each array element.

Toxicant signatures at the proteome level are also useful for toxicological screening, and should be analyzed in paraUel with toxicant signatures at the transcript level There is a poor correlation between transcript and protein abundances for some proteins in some tissues (Anderson, N.L. and J. Seilhamer (1997) Electrophoresis 18:533-537), so proteome toxicant signatures may be useful in the analysis of compounds which do not significantly affect the transcript image, but which alter the proteomic profile. In addition, the analysis of transcripts in body fluids is difficult, due to rapid degradation of mRNA, so proteomic profiUng may be more reUable and informative in such cases.

In another embodiment, the toxicity of a test compound is assessed by treating a biological sample containing proteins with the test compound. Proteins that are expressed in the treated biological sample are separated so that the amount of each protein can be quantified. The amount of each protein is compared to the amount of the corresponding protein in an untreated biological sample. A difference in the amount of protein between the two samples is indicative of a toxic response to the test compound in the treated sample. Individual proteins are identified by sequencing the amino acid residues of the individual proteins and comparing these partial sequences to the polypeptides of the present invention.

In another embodiment, the toxicity of a test compound is assessed by treating a biological sample containing proteins with the test compound. Proteins from the biological sample are incubated with antibodies specific to the polypeptides of the present invention. The amount of protein recognized by the antibodies is quantified. The amount of protein in the treated biological sample is compared with the amount in an untreated biological sample. A difference in the amount of protein between the two samples is indicative of a toxic response to the test compound in the treated sample.

Microarrays may be prepared, used, and analyzed using methods known in the art. (See, e.g., Brennan, T.M. et al. (1995) U.S. Patent No. 5,474,796; Schena, M. et al (1996) Proc. Natl Acad. Sci. USA 93:10614-10619; Baldeschweiler et al. (1995) PCT appUcation W095/251116; Shalon, D, et al. (1995) PCT appUcation WO95/35505; HeUer, R.A. et al. (1997) Proc. Natl. Acad. Sci. USA 94:2150-2155; and HeUer, MJ. et al. (1997) U.S. Patent No. 5,605,662.) Various types of microarrays are well known and thoroughly described in DNA Microarrays: A Practical Approach, M. Schena, ed. (1999) Oxford University Press, Exindon, hereby expressly incorporated by reference. In another embodiment of the invention, nucleic acid sequences encoding OXRD may be used to generate hybridization probes useful in mapping the naturally occurring genomic sequence. Either coding or noncoding sequences may be used, and in some instances, npncoding sequences may be preferable over coding sequences. For example, conservation of a coding sequence among members of a multi-gene family may potentiaUy cause undesired cross hybridization during chromosomal mapping. The sequences may be mapped to a particular chromosome, to a specific region of a chromosome, or to artificial chromosome constructions, e.g., human artificial chromosomes (HACs), yeast artificial chromosomes (YACs), bacterial artificial chromosomes (BACs), bacterial PI constructions, or single chromosome cDNA Ubraries. (See, e.g., Harrington, J.J. et al. (1997) Nat. Genet. 15:345-355; Price, CM. (1993) Blood Rev. 7:127-134; and Trask, B.J. (1991) Trends Genet. 7:149-154.) Once mapped, the nucleic acid sequences of the invention may be used to develop genetic Unkage maps, for example, which correlate the inheritance of a disease state with the inheritance of a particular chromosome region or restriction fragment length polymorphism (RFLP). (See, for example, Lander, E.S. and D. Botstein (1986) Proc. Natl. Acad. Sci. USA 83:7353-7357.) Fluorescent in situ hybridization (FISH) may be correlated with other physical and genetic map data. (See, e.g., Heinz-Ulrich, et al. (1995) in Meyers, supra, pp. 965-968.) Examples of genetic map data can be found in various scientific journals or at the OnUne MendeUan Inheritance in Man (OMEvI) World Wide Web site. Correlation between the location of the gene encoding OXRD on a physical map and a specific disorder, or a predisposition to a specific disorder, may help define the region of DNA associated with that disorder and thus may further positional cloning efforts.

In situ hybridization of chromosomal preparations and physical mapping techniques, such as Unkage analysis using estabUshed chromosomal markers, may be used for extending genetic maps. Often the placement of a gene on the chromosome of another mammaUan species, such as mouse, may reveal associated markers even if the exact chromosomal locus is not known. This information is valuable to investigators searching for disease genes using positional cloning or other gene discovery techniques. Once the gene or genes responsible for a disease or syndrome have been crudely locaUzed by genetic Unkage to a particular genomic region, e.g., ataxia-telangiectasia to 1 lq22-23, any sequences mapping to that area may represent associated or regulatory genes for further investigation. (See, e.g., Gatti, R.A. et al. (1988) Nature 336:577-580.) The nucleotide sequence of the instant invention may also be used to detect differences in the chromosomal location due to translocation, inversion, etc., among normal, carrier, or affected individuals.

In another embodiment of the invention, OXRD, its catalytic or immunogenic fragments, or oUgopeptides thereof can be used for screening Ubraiies of compounds in any of a variety of drag screening techniques. The fragment employed in such screening may be free in solution, affixed to a soUd support, borne on a cell surface, or located intraceUularly. The formation of binding complexes between OXRD and the agent being tested may be measured.

Another technique for drag screening provides for high throughput screening of compounds having suitable binding affinity to the protein of interest. (See, e.g., Geysen, et al. (1984) PCT appUcation WO84/03564.) In this method, large numbers of different small test compounds are synthesized on a soUd substrate. The test compounds are reacted with OXRD, or fragments thereof, and washed. Bound OXRD is then detected by methods weU known in the art. Purified OXRD can also be coated directly onto plates for use in the aforementioned drag screening techniques. Alternatively, non-neutiaUzing antibodies can be used to capture the peptide and immobiUze it on a soUd support.

In another embodiment, one may use competitive drag screening assays in which neutraUzing antibodies capable of binding OXRD specificaUy compete with a test compound for binding OXRD. In this manner, antibodies can be used to detect the presence of any peptide which shares one or more antigenic determinants with OXRD.

In additional embodiments, the nucleotide sequences which encode OXRD may be used in any molecular biology techniques that have yet to be developed, provided the new techniques rely on properties of nucleotide sequences that are currently known, including, but not Umited to, such properties as the triplet genetic code and specific base pair interactions.

Without further elaboration, it is beUeved that one skiUed in the art can, using the preceding description, utilize the present invention to its fuUest extent. The foUowing embodiments are, therefore, to be construed as merely iUustrative, and not Umitative of the remainder of the disclosure in any way whatsoever.

The disclosures of all patents, appUcations and pubUcations, mentioned above and below, including U.S. Ser. No. 60/257,802 and U.S. Ser. No. 60/262,901, are expressly incorporated by reference herein.

EXAMPLES

I. Construction of cDNA Libraries

Incyte cDNAs were derived from cDNA Ubraries described in the LIFESEQ GOLD database (Incyte Genomics, Palo Alto CA). Some tissues were homogenized and lysed in guanidinium isothiocyanate, while others were homogenized and lysed in phenol or in a suitable mixture of denaturants, such as TRIZOL (Life Technologies), a monophasic solution of phenol and guanidine isothiocyanate. The resulting lysates were centrifuged over CsCl cushions or extracted with chloroform. RNA was precipitated from the lysates with either isopropanol or sodium acetate and ethanol or by other routine methods.

Phenol extraction and precipitation of RNA were repeated as necessary to increase RNA purity. In some cases, RNA was treated with DNase. For most Ubraries, poly(A)+ RNA was isolated using oUgo d(T)-coupled paramagnetic particles (Promega), OLIGOTEX latex particles (QIAGEN, Chatsworth CA), or an OLIGOTEX mRNA purification kit (QLAGEN). Alternatively, RNA was isolated directly from tissue lysates using other RNA isolation kits, e.g., the POLY(A)PURE mRNA purification kit (Ambion, Austin TX). In some cases, Stratagene was provided with RNA and constructed the corresponding cDNA Ubraries. Otherwise, cDNA was synthesized and cDNA Ubraries were constructed with the UNIZAP vector system (Stratagene) or SUPERSCRIPT plasmid system (Life Technologies), using the recommended procedures or similar methods known in the art. (See, e.g., Ausubel, 1997, supra, units 5.1-6.6.) Reverse transcription was initiated using oUgo d(T) or random primers. Synthetic oUgonucleotide adapters were Ugated to double stranded cDNA, and the cDNA was digested with the appropriate restriction enzyme or enzymes. For most Ubraries, the cDNA was size-selected (300- 1000 bp) using SEPHACRYL S1000, SEPHAROSE CL2B, or SEPHAROSE CL4B column chromatography (Amersham Pharmacia Biotech) or preparative agarose gel electrophoresis. cDNAs were Ugated into compatible restriction enzyme sites of the polyUnker of a suitable plasmid, e.g., PBLUESCREPT plasmid (Stratagene), PSPORT1 plasmid (Life Technologies), PCDNA2.1 plasmid (Invitrogen, Carlsbad CA), PBK-CMV plasmid (Stratagene), PCR2-TOPOTA plasmid (Invitrogen), PCMV-ICIS plasmid (Stratagene), pIGEN (Incyte Genomics, Palo Alto CA), pRARE (Incyte Genomics), or pINCY (Incyte Genomics), or derivatives thereof. Recombinant plasmids were transformed into competent E. coU ceUs including XLl-Blue, XLl-BlueMRF, or SOLR from Stiatagene or DH5α, DH10B, or ElectroMAX DH10B from Life Technologies.

II. Isolation of cDNA Clones

Plasmids obtained as described in Example I were recovered from host ceUs by in vivo excision using the UNIZAP vector system (Stratagene) or by ceU lysis. Plasmids were purified using at least one of the foUowing: a Magic or WIZARD Minipreps DNA purification system (Promega); an AGTC Miniprep purification kit (Edge Biosystems, Gaithersburg MD); and QIAWELL 8 Plasmid, QEAWELL 8 Plus Plasmid, QIAWELL 8 Ultra Plasmid purification systems or the R.E.A.L. PREP 96 plasmid purification kit from QIAGEN. FoUowing precipitation, plasmids were resuspended in 0.1 ml of distiUed water and stored, with or without lyophiUzation, at 4°C

Alternatively, plasmid DNA was ampUfied from host cell lysates using direct Unk PCR in a high-throughput format (Rao, V.B. (1994) Anal. Biochem. 216:1-14). Host cell lysis and thermal cycUng steps were carried out in a single reaction mixture. Samples were processed and stored in 384-weU plates, and the concentration of ampUfied plasmid DNA was quantified fluorometrically using PICOGREEN dye (Molecular Probes, Eugene OR) and a FLUOROSKAN π fluorescence scanner (Labsystems Oy, Helsinki, Finland).

III. Sequencing and Analysis

Incyte cDNA recovered in plasmids as described in Example U were sequenced as foUows. Sequencing reactions were processed using standard methods or high-throughput instrumentation such as the ABI CATALYST 800 (AppUed Biosystems) thermal cycler or the PTC-200 thermal cycler (MJ Research) in conjunction with the HYDRA microdispenser (Robbins Scientific) or the MICROLAB 2200 (Hamilton) Uquid transfer system. cDNA sequencing reactions were prepared using reagents provided by Amersham Pharmacia Biotech or suppUed in ABI sequencing kits such as the ABI PRISM BIGDYE Terminator cycle sequencing ready reaction kit (AppUed Biosystems). Electiophoretic separation of cDNA sequencing reactions and detection of labeled polynucleotides were carried out using the MEGABACE 1000 DNA sequencing system (Molecular Dynamics); the ABI PRISM 373 or 377 sequencing system (AppUed Biosystems) in conjunction with standard ABI protocols and base caUing software; or other sequence analysis systems known in the art. Reading frames within the cDNA sequences were identified using standard methods (reviewed in Ausubel, 1997, supra, unit 7.7). Some of the cDNA sequences were selected for extension using the techniques disclosed in Example VTJJ.

The polynucleotide sequences derived from Incyte cDNAs were vaUdated by removing vector, Unker, and poly(A) sequences and by masking ambiguous bases, using algorithms and programs based on BLAST, dynamic programming, and dinucleotide nearest neighbor analysis. The Incyte cDNA sequences or translations thereof were then queried against a selection of pubUc databases such as the GenBank primate, rodent, mammaUan, vertebrate, and eukaryote databases, and BLOCKS, PRINTS, DOMO, PRODOM; PROTEOME databases with sequences from Homo sapiens, Rattus norvegicus, Mus musculus, Caenorhabditis elegans, Saccharomvces cerevisiae. Schizosaccharomyces pombe, and Candida albicans (Incyte Genomics, Palo Alto CA); and hidden Markov model (HMM)-based protein family databases such as PFAM. (HMM is a probabiUstic approach which analyzes consensus primary structures of gene families. See, for example, Eddy, S.R. (1996) Curr. Opin. Stract. Biol. 6:361-365.) The queries were performed using programs based on BLAST, FASTA, BLIMPS, and HMMER. The Incyte cDNA sequences were assembled to produce full length polynucleotide sequences. Alternatively, GenBank cDNAs, GenBank ESTs, stitched sequences, stretched sequences, or Genscan-predicted coding sequences (see Examples IV and V) were used to extend Incyte cDNA assemblages to fuU length. Assembly was performed using programs based on Phred, Phrap, and Consed, and cDNA assemblages were screened for open reading frames using programs based on GeneMark, BLAST, and FASTA. The fuU length polynucleotide sequences were translated to derive the corresponding fuU length polypeptide sequences. Alternatively, a polypeptide of the invention may begin at any of the methionine residues of the full length translated polypeptide. FuU length polypeptide sequences were subsequently analyzed by querying against databases such as the GenBank protein databases (genpept), SwissProt, the PROTEOME databases, BLOCKS, PRINTS, DOMO, PRODOM, Prosite, and hidden Markov model (HMM)-based protein family databases such as PFAM. FuU length polynucleotide sequences are also analyzed using MACDNASIS PRO software (Hitachi Software Engineering, South San Francisco CA) and LASERGENE software (DNASTAR). Polynucleotide and polypeptide sequence aUgnments are generated using default parameters specified by the CLUSTAL algorithm as incorporated into the MEGALIGN multisequence aUgnment program (DNASTAR), which also calculates the percent identity between aUgned sequences.

Table 7 summarizes the tools, programs, and algorithms used for the analysis and assembly of Incyte cDNA and fuU length sequences and provides appUcable descriptions, references, and threshold parameters. The first column of Table 7 shows the tools, programs, and algorithms used, the second column provides brief descriptions thereof, the third column presents appropriate references, aU of which are incorporated by reference herein in their entirety, and the fourth column presents, where appUcable, the scores, probabiUty values, and other parameters used to evaluate the strength of a match between two sequences (the higher the score or the lower the probabiUty value, the greater the identity between two sequences).

The programs described above for the assembly and analysis of fuU length polynucleotide and polypeptide sequences were also used to identify polynucleotide sequence fragments from SEQ JD NO:4-6. Fragments from about 20 to about 4000 nucleotides which are useful in hybridization and ampUfication technologies are described in Table 4, column 2.

IV. Identification and Editing of Coding Sequences from Genomic DNA

Putative oxidoreductases were initiaUy identified by running the Genscan gene identification program against pubUc genomic sequence databases (e.g., gbpri and gbhtg). Genscan is a general- purpose gene identification program which analyzes genomic DNA sequences from a variety of organisms (See Burge, C and S. KarUn (1997) J. Mol. Biol. 268:78-94, and Burge, C. and S. KarUn (1998) Curr. Opin. Stract. Biol. 8:346-354). The program concatenates predicted exons to form an assembled cDNA sequence extending from a methionine to a stop codon. The output of Genscan is a FASTA database of polynucleotide and polypeptide sequences. The maximum range of sequence for Genscan to analyze at once was set to 30 kb. To determine which of these Genscan predicted cDNA sequences encode oxidoreductases, the encoded polypeptides were analyzed by querying against PFAM models for oxidoreductases. Potential oxidoreductases were also identified by homology to Incyte cDNA sequences that had been annotated as oxidoreductases. These selected Genscan-predicted sequences were then compared by BLAST analysis to the genpept and gbpri pubUc databases. Where necessary, the Genscan-predicted sequences were then edited by comparison to the top BLAST hit from genpept to correct errors in the sequence predicted by Genscan, such as extra or omitted exons. BLAST analysis was also used to find any Incyte cDNA or pubUc cDNA coverage of the Genscan-predicted sequences, thus providing evidence for transcription. When Incyte cDNA coverage was available, this information was used to correct or confirm the Genscan predicted sequence. FuU length polynucleotide sequences were obtained by assembUng Genscan-predicted coding sequences with Encyte cDNA sequences and/or pubUc cDNA sequences using the assembly process described in Example HI. Alternatively, full length polynucleotide sequences were derived entirely from edited or unedited Genscan-predicted coding sequences. V. Assembly of Genomic Sequence Data with cDNA Sequence Data "Stitched" Sequences

Partial cDNA sequences were extended with exons predicted by the Genscan gene identification program described in Example IN Partial cDΝAs assembled as described in Example H were mapped to genomic DΝA and parsed into clusters containing related cDΝAs and Genscan exon predictions from one or more genomic sequences. Each cluster was analyzed using an algorithm based on graph theory and dynamic programming to integrate cDΝA and genomic information, generating possible spUce variants that were subsequently confirmed, edited, or extended to create a fuU length sequence. Sequence intervals in which the entire length of the interval was present on more than one sequence in the cluster were identified, and intervals thus identified were considered to be equivalent by transitivity. For example, if an interval was present on a cDΝA and two genomic sequences, then aU three intervals were considered to be equivalent. This process aUows unrelated but consecutive genomic sequences to be brought together, bridged by cDΝA sequence. Intervals thus identified were then "stitched" together by the stitching algorithm in the order that they appear along their parent sequences to generate the longest possible sequence, as weU as sequence variants. Linkages between intervals which proceed along one type of parent sequence (cDΝA to cDΝA or genomic sequence to genomic sequence) were given preference over Unkages which change parent type (cDΝA to genomic sequence). The resultant stitched sequences were translated and compared by BLAST analysis to the genpept and gbpri pubUc databases. Incorrect exons predicted by Genscan were corrected by comparison to the top BLAST hit from genpept. Sequences were further extended with additional cDΝA sequences, or by inspection of genomic DΝA, when necessary. "Stretched" Sequences

Partial DΝA sequences were extended to fuU length with an algorithm based on BLAST analysis. First, partial cDΝAs assembled as described in Example HI were queried against pubUc databases such as the GenBank primate, rodent, mammalian, vertebrate, and eukaryote databases using the BLAST program. The nearest GenBank protein homolog was then compared by BLAST analysis to either Incyte cDΝA sequences or GenScan exon predicted sequences described in Example IN. A chimeric protein was generated by using the resultant high-scoring segment pairs (HSPs) to map the translated sequences onto the GenBank protein homolog. Insertions or deletions may occur in the chimeric protein with respect to the original GenBank protein homolog. The GenBank protein homolog, the chimeric protein, or both were used as probes to search for homologous genomic sequences from the pubUc human genome databases. Partial DΝA sequences were therefore "stretched" or extended by the addition of homologous genomic sequences. The resultant stretched sequences were examined to determine whether it contained a complete gene.

VI. Chromosomal Mapping of OXRD Encoding Polynucleotides

The sequences which were used to assemble SEQ JD NO:4-6 were compared with sequences from the Incyte LIFESEQ database and pubUc domain databases using BLAST and other implementations of the Smith- Waterman algorithm. Sequences from these databases that matched SEQ JD NO:4-6 were assembled into clusters of contiguous and overlapping sequences using assembly algorithms such as Phrap (Table 7). Radiation hybrid and genetic mapping data available from pubUc resources such as the Stanford Human Genome Center (SHGC), Whitehead Institate for Genome Research (WIGR), and Genethon were used to determine if any of the clustered sequences had been previously mapped. Inclusion of a mapped sequence in a cluster resulted in the assignment of aU sequences of that cluster, including its particular SEQ ED NO:, to that map location.

Map locations are represented by ranges, or intervals, of human chromosomes. The map position of an interval, in centiMorgans, is measured relative to the terminus of the chromosome's p- arm. (The centiMorgan (cM) is a unit of measurement based on recombination frequencies between chromosomal markers. On average, 1 cM is roughly equivalent to 1 megabase (Mb) of DNA in humans, although this can vary widely due to hot and cold spots of recombination.) The cM distances are based on genetic markers mapped by Genethon which provide boundaries for radiation hybrid markers whose sequences were included in each of the clusters. Human genome maps and other resources available to the pubUc, such as the NCBI "GeneMap'99" World Wide Web site

(http://www.ncbi.nUn.nih.gov/genemap/), can be employed to determine if previously identified disease genes map within or in proximity to the intervals indicated above.

VII. Analysis of Polynucleotide Expression

Northern analysis is a laboratory technique used to detect the presence of a transcript of a gene and involves the hybridization of a labeled nucleotide sequence to a membrane on which RNAs from a particular cell type or tissue have been bound. (See, e.g., Sambrook, supra, ch. 7; Ausubel (1995) supra, ch. 4 and 16.)

Analogous computer techniques applying BLAST were used to search for identical or related molecules in cDNA databases such as GenBank or LIFESEQ (Incyte Genomics). This analysis is much faster than multiple membrane-based hybridizations. In addition, the sensitivity of the computer search can be modified to determine whether any particular match is categorized as exact or similar. The basis of the search is the product score, which is defined as: BLAST Score x Percent Identity 5 x minimum {length(Seq. 1), length(Seq. 2)}

The product score takes into account both the degree of similarity between two sequences and the length of the sequence match. The product score is a normaUzed value between 0 and 100, and is calculated as foUows: the BLAST score is multipUed by the percent nucleotide identity and the product is divided by (5 times the length of the shorter of the two sequences). The BLAST score is calculated by assigning a score of +5 for every base that matches in a high-scoring segment pair (HSP), and -4 for every mismatch. Two sequences may share more than one HSP (separated by gaps). Ef there is more than one HSP, then the pair with the highest BLAST score is used to calculate the product score. The product score represents a balance between fractional overlap and quaUty in a BLAST aUgnment. For example, a product score of 100 is produced only for 100% identity over the entire length of the shorter of the two sequences being compared. A product score of 70 is produced either by 100% identity and 70% overlap at one end, or by 88% identity and 100% overlap at the other. A product score of 50 is produced either by 100% identity and 50% overlap at one end, or 79% identity and 100% overlap.

Alternatively, polynucleotide sequences encoding OXRD are analyzed with respect to the tissue sources from which they were derived. For example, some full length sequences are assembled, at least in part, with overlapping Incyte cDNA sequences (see Example EH). Each cDNA sequence is derived from a cDNA Ubrary constructed from a human tissue. Each human tissue is classified into one of the foUowing organ/tissue categories: cardiovascular system; connective tissue; digestive system; embryonic structures; endocrine system; exocrine glands; genitaUa, female; genitaUa, male; germ ceUs; hemic and immune system; Uver; musculoskeletal system; nervous system; pancreas; respiratory system; sense organs; skin; stomaiognathic system; unclassified/mixed; or urinary tract. The number of Ubraries in each category is counted and divided by the total number of Ubraries across aU categories. Similarly, each human tissue is classified into one of the foUowing disease/condition categories: cancer, ceU Une, developmental, inflammation, neurological, trauma, cardiovascular, pooled, and other, and the number of Ubraries in each category is counted and divided by the total number of Ubraries across aU categories. The resulting percentages reflect the tissue- and disease-specific expression of cDNA encoding OXRD. cDNA sequences and cDNA Ubrary/tissue information are found in the LIFESEQ GOLD database (Incyte Genomics, Palo Alto CA). VIII. Extension of OXRD Encoding Polynucleotides FuU length polynucleotide sequences were also produced by extension of an appropriate fragment of the fuU length molecule using oUgonucleotide primers designed from this fragment. One primer was synthesized to initiate 5' extension of the known fragment, and the other primer was synthesized to initiate 3' extension of the known fragment. The initial primers were designed using OLIGO 4.06 software (National Biosciences), or another appropriate program, to be about 22 to 30 nucleotides in length, to have a GC content of about 50% or more, and to anneal to the target sequence at temperatures of about 68°C to about 72°C. Any stretch of nucleotides which would result in hairpin structures and primer-primer dimerizations was avoided.

Selected human cDNA Ubraries were used to extend the sequence. Ef more than one extension was necessary or desired, additional or nested sets of primers were designed.

High fideUty ampUfication was obtained by PCR using methods well known in the art. PCR was performed in 96-weU plates using the PTC-200 thermal cycler (MJ Research, Inc.). The reaction mix contained DNA template, 200 nmol of each primer, reaction buffer containing Mg ⁺, (NH₄)₂S0₄, and 2-mercaptoethanol, Taq DNA polymerase (Amersham Pharmacia Biotech), ELONGASE enzyme (Life Technologies), and Pfu DNA polymerase (Stratagene), with the foUowing parameters for primer pair PCI A and PCI B: Step 1: 94°C, 3 min; Step 2: 94°C, 15 sec; Step 3: 60°C, 1 min; Step 4: 68°C, 2 min; Step 5: Steps 2, 3, and 4 repeated 20 times; Step 6: 68°C, 5 min; Step 7: storage at 4°C In the alternative, the parameters for primer pair T7 and SK+ were as foUows: Step 1: 94°C, 3 min; Step 2: 94°C, 15 sec; Step 3: 57°C, 1 min; Step 4: 68°C, 2 min; Step 5: Steps 2, 3, and 4 repeated 20 times; Step 6: 68°C, 5 min; Step 7: storage at 4°C

The concentration of DNA in each weU was determined by dispensing 100 μl PICOGREEN quantitation reagent (0.25% (v/v) PICOGREEN; Molecular Probes, Eugene OR) dissolved in IX TE and 0.5 μl of undiluted PCR product into each weU of an opaque fluorimeter plate (Corning Costar, Acton MA), aUowing the DNA to bind to the reagent. The plate was scanned in a Fluoroskan IE (Labsystems Oy, Helsinki, Finland) to measure the fluorescence of the sample and to quantify the concentration of DNA. A 5 μl to 10 l aUquot of the reaction mixture was analyzed by electrophoresis on a 1 % agarose gel to determine which reactions were successful in extending the sequence.

The extended nucleotides were desalted and concentrated, transferred to 384-weU plates, digested with CviJI cholera virus endonuclease (Molecular Biology Research, Madison WI), and sonicated or sheared prior to reUgation into pUC 18 vector (Amersham Pharmacia Biotech). For shotgun sequencing, the digested nucleotides were separated on low concentration (0.6 to 0.8%) agarose gels, fragments were excised, and agar digested with Agar ACE (Promega). Extended clones were reUgated using T4 Ugase (New England Biolabs, Beverly MA) into pUC 18 vector (Amersham Pharmacia Biotech), treated with Pfu DNA polymerase (Stratagene) to fiU-in restriction site overhangs, and transfected into competent E. coU ceUs. Transformed ceUs were selected on antibiotic-containing media, and individual colonies were picked and cultured overnight at 37 °C in 384-weU plates in LB/2x carb Uquid media.

The ceUs were lysed, and DNA was ampUfied by PCR using Taq DNA polymerase (Amersham Pharmacia Biotech) and Pfu DNA polymerase (Stratagene) with the foUowing parameters: Step 1: 94 °C, 3 min; Step 2: 94 °C, 15 sec; Step 3: 60 °C, 1 min; Step 4: 72 °C, 2 min; Step 5: steps 2, 3, and 4 repeated 29 times; Step 6: 72°C, 5 min; Step 7: storage at 4°C DNA was quantified by PICOGREEN reagent (Molecular Probes) as described above. Samples with low DNA recoveries were reampUfied using the same conditions as described above. Samples were diluted with 20% dimethysulfoxide (1 :2, v/v), and sequenced using DYENAMIC energy transfer sequencing primers and the DYENAMIC DIRECT kit (Amersham Pharmacia Biotech) or the ABI PRISM BIGDYE Terminator cycle sequencing ready reaction kit (AppUed Biosystems). n Uke manner, full length polynucleotide sequences are verified using the above procedure or are used to obtain 5' regulatory sequences using the above procedure along with oUgonucleotides designed for such extension, and an appropriate genomic Ubrary. IX. Labeling and Use of Individual Hybridization Probes

Hybridization probes derived from SEQ JD NO:4-6 are employed to screen cDNAs, genomic DNAs, or RNAs. Although the labeUng of oUgonucleotides, consisting of about 20 base pairs, is specificaUy described, essentiaUy the same procedure is used with larger nucleotide fragments. OUgonucleotides are designed using state-of-the-art software such as OLIGO 4.06 software (National Biosciences) and labeled by combining 50 pmol of each oUgomer, 250 Ci of [γ-³²P] adenosine triphosphate (Amersham Pharmacia Biotech), and T4 polynucleotide kinase (DuPont NEN, Boston MA). The labeled oUgonucleotides are substantiaUy purified using a SEPHADEX G-25 superfine size exclusion dextran bead column (Amersham Pharmacia Biotech). An aUquot containing 10⁷ counts per minute of the labeled probe is used in a typical membrane-based hybridization analysis of human genomic DNA digested with one of the foUowing endonucleases: Ase I, Bgl IE, Eco RI, Pst I, Xba I, or Pvu EC (DuPont NEN). The DNA from each digest is fractionated on a 0.7% agarose gel and transferred to nylon membranes (Nytran Plus, Schleicher & SchueU, Durham NH). Hybridization is carried out for 16 hours at 40 °C To remove nonspecific signals, blots are sequentiaUy washed at room temperature under conditions of up to, for example, 0.1 x saUne sodium citrate and 0.5% sodium dodecyl sulfate. Hybridization patterns are visuaUzed using autoradiography or an alternative imaging means and compared.

X. Microarrays

The Unkage or synthesis of array elements upon a microarray can be achieved utiUzing photoUthography, piezoelectric printing (ink-jet printing, See, e.g., Baldeschweiler, supra.), mechanical microspotting technologies, and derivatives thereof. The substrate in each of the aforementioned technologies should be uniform and soUd with a non-porous surface (Schena (1999), supra). Suggested substrates include siUcon, siUca, glass sUdes, glass chips, and siUcon wafers. Alternatively, a procedure analogous to a dot or slot blot may also be used to arrange and Unk elements to the surface of a substrate using thermal, UN, chemical, or mechanical bonding procedures. A typical array may be produced using available methods and machines weU known to those of ordinary skiU in the art and may contain any appropriate number of elements. (See, e.g., Schena, M. et al. (1995) Science 270:467-470; Shalon, D. et al. (1996) Genome Res. 6:639-645; MarshaU, A. and J. Hodgson (1998) Nat. Biotechnol. 16:27-31.) Full length cDNAs, Expressed Sequence Tags (ESTs), or fragments or oUgomers thereof may comprise the elements of the microarray. Fragments or oUgomers suitable for hybridization can be selected using software well known in the art such as LASERGENE software (DNASTAR). The array elements are hybridized with polynucleotides in a biological sample. The polynucleotides in the biological sample are conjugated to a fluorescent label or other molecular tag for ease of detection. After hybridization, nonhybridized nucleotides from the biological sample are removed, and a fluorescence scanner is used to detect hybridization at each array element. Alternatively, laser desorbtion and mass spectrometry may be used for detection of hybridization. The degree of complementarity and the relative abundance of each polynucleotide which hybridizes to an element on the microarray may be assessed. In one embodiment, microarray preparation and usage is described in detail below.

Tissue or Cell Sample Preparation

Total RNA is isolated from tissue samples using the guanidinium thiocyanate method and poly(A)⁺ RNA is purified using the oUgo-(dT) ceUulose method. Each poly(A)⁺ RNA sample is reverse transcribed using MMLV reverse-transcriptase, 0.05 pg/μl oUgo-(dT) primer (21mer), IX first strand buffer, 0.03 units/μl RNase inhibitor, 500 μM dATP, 500 μM dGTP, 500 μM dTTP, 40 μM dCTP, 40 μM dCTP-Cy3 (BDS) or dCTP-Cy5 (Amersham Pharmacia Biotech). The reverse transcription reaction is performed in a 25 ml volume containing 200 ng poly(A)⁺ RNA with GEMBRIGHT kits (Incyte). Specific control poly(A)⁺ RNAs are synthesized by in vitro transcription from non-coding yeast genomic DNA. After incubation at 37° C for 2 hr, each reaction sample (one with Cy3 and another with Cy5 labeUng) is treated with 2.5 ml of 0.5M sodium hydroxide and incubated for 20 minutes at 85° C to the stop the reaction and degrade the RNA. Samples are purified using two successive CHROMA SPIN 30 gel filtration spin columns (CLONTECH Laboratories, Inc. (CLONTECH), Palo Alto CA) and after combining, both reaction samples are ethanol precipitated using 1 ml of glycogen (1 mg/ml), 60 ml sodium acetate, and 300 ml of 100% ethanol. The sample is then dried to completion using a SpeedVAC (Savant Instruments Inc., Holbrook NY) and resuspended in 14 μl 5X SSC/0.2% SDS. Microarray Preparation Sequences of the present invention are used to generate array elements. Each array element is ampUfied from bacterial ceUs containing vectors with cloned cDNA inserts. PCR ampUfication uses primers complementary to the vector sequences flanking the cDNA insert. Array elements are ampUfied in thirty cycles of PCR from an initial quantity of 1-2 ng to a final quantity greater than 5 μg. AmpUfied array elements are then purified using SEPHACRYL-400 (Amersham Pharmacia Biotech).

Purified array elements are immobiUzed on polymer-coated glass sUdes. Glass microscope sUdes (Corning) are cleaned by ultrasound in 0.1% SDS and acetone, with extensive distiUed water washes between and after treatments. Glass sUdes are etched in 4% hydrofluoric acid (VWR Scientific Products Corporation (VWR), West Chester PA), washed extensively in distiUed water, and coated with 0.05% aminopropyl silane (Sigma) in 95% ethanol Coated sUdes are cured in a 110°C oven.

Array elements are appUed to the coated glass substrate using a procedure described in U.S. Patent No. 5,807,522, incorporated herein by reference. 1 μl of the array element DNA, at an average concentration of 100 ng/μl, is loaded into the open capiUary printing element by a high-speed robotic apparatus. The apparatus then deposits about 5 nl of array element sample per sUde.

Microarrays are UV-crossUnked using a STRATALENKER UV-crossUnker (Stratagene). Microarrays are washed at room temperature once in 0.2% SDS and three times in distiUed water. Non-specific binding sites are blocked by incubation of microarrays in 0.2% casein in phosphate buffered saUne (PBS) (Tropix, Inc., Bedford MA) for 30 minutes at 60° C foUowed by washes in 0.2% SDS and distiUed water as before. Hybridization

Hybridization reactions contain 9 μl of sample mixture consisting of 0.2 μg each of Cy3 and Cy5 labeled cDNA synthesis products in 5X SSC, 0.2% SDS hybridization buffer. The sample mixture is heated to 65° C for 5 minutes and is aUquoted onto the microarray surface and covered with an 1.8 cm² coversUp. The arrays are transferred to a waterproof chamber having a cavity just sUghtly larger than a microscope sUde. The chamber is kept at 100% humidity internaUy by the addition of 140 μl of 5X SSC in a corner of the chamber. The chamber containing the arrays is incubated for about 6.5 hours at 60° C The arrays are washed for 10 min at 45° C in a first wash buffer (IX SSC, 0.1% SDS), three times for 10 minutes each at 45° C in a second wash buffer (0.1X SSC), and dried. Detection

Reporter-labeled hybridization complexes are detected with a microscope equipped with an Ennova 70 mixed gas 10 W laser (Coherent, Inc., Santa Clara CA) capable of generating spectral

Unes at 488 nm for excitation of Cy3 and at 632 nm for excitation of Cy5. The excitation laser Ught is focused on the array using a 20X microscope objective (Nikon, Inc., MelviUe NY). The sUde containing the array is placed on a computer-controUed X-Y stage on the microscope and raster- scanned past the objective. The 1.8 cm x 1.8 cm array used in the present example is scanned with a resolution of 20 micrometers.

In two separate scans, a mixed gas multiUne laser excites the two fluorophores sequentially. Emitted Ught is spUt, based on wavelength, into two photomultipUer tube detectors (PMT R1477, Hamamatsu Photonics Systems, Bridgewater NJ) corresponding to the two fluorophores. Appropriate filters positioned between the array and the photomultipUer tubes are used to filter the signals. The emission maxima of the fluorophores used are 565 nm for Cy3 and 650 nm for Cy5. Each array is typicaUy scanned twice, one scan per fluorophore using the appropriate filters at the laser source, although the apparatus is capable of recording the spectra from both fluorophores simultaneously.

The sensitivity of the scans is typicaUy caUbrated using the signal intensity generated by a cDNA control species added to the sample mixture at a known concentration. A specific location on the array contains a complementary DNA sequence, aUowing the intensity of the signal at that location to be correlated with a weight ratio of hybridizing species of 1:100,000. When two samples from different sources (e.g., representing test and control ceUs), each labeled with a different fluorophore, are hybridized to a single array for the purpose of identifying genes that are differentiaUy expressed, the caUbration is done by labeUng samples of the calibrating cDNA with the two fluorophores and adding identical amounts of each to the hybridization mixture.

The output of the photomultipUer tube is digitized using a 12-bit RTI-835H analog-to-digital (A/D) conversion board (Analog Devices, Inc., Norwood MA) instaUed in an IBM-compatible PC computer. The digitized data are displayed as an image where the signal intensity is mapped using a Unear 20-color transformation to a pseudocolor scale ranging from blue (low signal) to red (high signal). The data is also analyzed quantitatively. Where two different fluorophores are excited and measured simultaneously, the data are first corrected for optical crosstalk (due to overlapping emission spectra) between the fluorophores using each fluorophore's emission spectrum.

A grid is superimposed over the fluorescence signal image such that the signal from each spot is centered in each element of the grid. The fluorescence signal within each element is then integrated to obtain a numerical value corresponding to the average intensity of the signal. The software used for signal analysis is the GEMTOOLS gene expression analysis program (Incyte). XI. Complementary Polynucleotides

Sequences complementary to the OXRD-encoding sequences, or any parts thereof, are used to detect, decrease, or inhibit expression of naturaUy occurring OXRD. Although use of oUgonucleotides comprising from about 15 to 30 base pairs is described, essentiaUy the same procedure is used with smaUer or with larger sequence fragments. Appropriate oUgonucleotides are designed using OLIGO 4.06 software (National Biosciences) and the coding sequence of OXRD. To inhibit transcription, a complementary oUgonucleotide is designed from the most unique 5' sequence and used to prevent promoter binding to the coding sequence. To inhibit translation, a complementary oUgonucleotide is designed to prevent ribosomal binding to the OXRD-encoding transcript. XII. Expression of OXRD Expression and purification of OXRD is achieved using bacterial or virus-based expression systems. For expression of OXRD in bacteria, cDNA is subcloned into an appropriate vector containing an antibiotic resistance gene and an inducible promoter that directs high levels of cDNA transcription. Examples of such promoters include, but are not Umited to, the trp-lac (tac) hybrid promoter and the T5 or T7 bacteriophage promoter in conjunction with the lac operator regulatory element. Recombinant vectors are transformed into suitable bacterial hosts, e.g., BL21 (DE3). Antibiotic resistant bacteria express OXRD upon induction with isopropyl beta-D- thiogalactopyranoside (EPTG). Expression of OXRD in eukaryotic ceUs is achieved by infecting insect or mammaUan ceU Unes with recombinant Autographica caUfornica nuclear polyhedrosis virus (AcMNPV), commonly known as baculoviras. The nonessential polyhedrin gene of baculoviras is replaced with cDNA encoding OXRD by either homologous recombination or bacterial-mediated transposition involving transfer plasmid intermediates. Viral infectivity is maintained and the strong polyhedrin promoter drives high levels of cDNA transcription. Recombinant baculoviras is used to infect Spodoptera frugiperda (Sf9) insect ceUs in most cases, or human hepatocytes, in some cases. Infection of the latter requires additional genetic modifications to baculoviras. (See Engelhard, E.K. et al. (1994) Proc. Natl. Acad. Sci. USA 91:3224-3227; Sandig, V. et al. (1996) Hum. Gene Ther. 7:1937-1945.)

In most expression systems, OXRD is synthesized as a fusion protein with, e.g., glutathione S-transferase (GST) or a peptide epitope tag, such as FLAG or 6-His, permitting rapid, single-step, affinity-based purification of recombinant fusion protein from crude ceU lysates. GST, a 26-kilodalton enzyme from Scbistosoma iaponicum, enables the purification of fusion proteins on immobiUzed glutathione under conditions that maintain protein activity and antigenicity (Amersham Pharmacia Biotech). FoUowing purification, the GST moiety can be proteolyticaUy cleaved from OXRD at specificaUy engineered sites. FLAG, an 8-amino acid peptide, enables immunoaffinity purification using commerciaUy available monoclonal and polyclonal anti-FLAG antibodies (Eastman Kodak). 6- His, a stretch of six consecutive histidine residues, enables purification on metal-chelate resins (QIAGEN). Methods for protein expression and purification are discussed in Ausubel (1995, supra, ch. 10 and 16). Purified OXRD obtained by these methods can be used directly in the assays shown in Examples XVT, XVII, and XVEEE, where appUcable. XIII. Functional Assays

OXRD function is assessed by expressing the sequences encoding OXRD at physiologically elevated levels in mammaUan ceU culture systems. cDNA is subcloned into a mammaUan expression vector containing a strong promoter that drives high levels of cDNA expression. Vectors of choice include PCMV SPORT (Life Technologies) and PCR3.1 (Invitrogen, Carlsbad CA), both of which contain the cytomegalo virus promoter. 5-10 μg of recombinant vector are transiently transfected into a human ceU Une, for example, an endotheUal or hematopoietic cell Une, using either Uposome formulations or electroporation. 1-2 μg of an additional plasmid containing sequences encoding a marker protein are co-transfected. Expression of a marker protein provides a means to distinguish transfected ceUs from nontransfected ceUs and is a reUable predictor of cDNA expression from the recombinant vector. Marker proteins of choice include, e.g., Green Fluorescent Protein (GFP; Clontech), CD64, or a CD64-GFP fusion protein. Flow cytometry (FCM), an automated, laser optics-based technique, is used to identify transfected ceUs expressing GFP or CD64-GFP and to evaluate the apoptotic state of the ceUs and other ceUular properties. FCM detects and quantifies the uptake of fluorescent molecules that diagnose events preceding or coincident with ceU death. These events include changes in nuclear DNA content as measured by staining of DNA with propidium iodide; changes in ceU size and granularity as measured by forward Ught scatter and 90 degree side light scatter; down-regulation of DNA synthesis as measured by decrease in bromodeoxyuridine uptake; alterations in expression of ceU surface and intraceUular proteins as measured by reactivity with specific antibodies; and alterations in plasma membrane composition as measured by the binding of fluorescein-conjugated Annexin V protein to the ceU surface. Methods in flow cytometry are discussed in Ormerod, M.G. (1994) Flow Cytometry, Oxford, New York NY. The influence of OXRD on gene expression can be assessed using highly purified populations of ceUs transfected with sequences encoding OXRD and either CD64 or CD64-GFP. CD64 and CD64-GFP are expressed on the surface of transfected ceUs and bind to conserved regions of human immunoglobuUn G (IgG). Transfected ceUs are efficiently separated from nontransfected ceUs using magnetic beads coated with either human IgG or antibody against CD64 (DYNAL, Lake Success NY). mRNA can be purified from the ceUs using methods weU known by those of skiU in the art. Expression of mRNA encoding OXRD and other genes of interest can be analyzed by northern analysis or microarray techniques. XIV. Production of OXRD Specific Antibodies

OXRD substantiaUy purified using polyacrylamide gel electrophoresis (PAGE; see, e.g., Harrington, M.G. (1990) Methods Enzymol. 182:488-495), or other purification techniques, is used to immunize rabbits and to produce antibodies using standard protocols.

Alternatively, the OXRD amino acid sequence is analyzed using LASERGENE software (DNASTAR) to determine regions of high immunogenicity, and a corresponding oUgopeptide is synthesized and used to raise antibodies by means known to those of skiU in the art. Methods for selection of appropriate epitopes, such as those near the C-terminus or in hydrophiUc regions are weU described in the art. (See, e.g., Ausubel, 1995, supra, ch. 11.)

TypicaUy, oUgopeptides of about 15 residues in length are synthesized using an ABI 431 A peptide synthesizer (AppUed Biosystems) using FMOC chemistry and coupled to KLH (Sigma- Aldrich, St. Louis MO) by reaction with N-maleimidobenzoyl-N-hydroxysuccinimide ester (MBS) to increase immunogenicity. (See, e.g., Ausubel, 1995, supra.) Rabbits are immunized with the oUgopeptide-KLH complex in complete Freund's adjuvant. Resulting antisera are tested for antipeptide and anti-OXRD activity by, for example, binding the peptide or OXRD to a substrate, blocking with 1% BSA, reacting with rabbit antisera, washing, and reacting with radio-iodinated goat anti-rabbit IgG. XV. Purification of Naturally Occurring OXRD Using Specific Antibodies

NaturaUy occurring or recombinant OXRD is substantiaUy purified by immunoaffinity chromatography using antibodies specific for OXRD. An immunoaffinity column is constructed by covalently coupUng anti-OXRD antibody to an activated chromatographic resin, such as CNBr-activated SEPHAROSE (Amersham Pharmacia Biotech). After the coupUng, the resin is blocked and washed according to the manufacturer's instructions.

Media containing OXRD are passed over the immunoaffinity column, and the column is washed under conditions that aUow the preferential absorbance of OXRD (e.g., high ionic strength buffers in the presence of detergent). The column is eluted under conditions that disrupt antibody/OXRD binding (e.g., a buffer of pH 2 to pH 3, or a high concentration of a chaotrope, such as urea or thiocyanate ion), and OXRD is coUected.

XVI. Identification of Molecules Which Interact with OXRD

OXRD, or biologicaUy active fragments thereof, are labeled with ¹²⁵I Bolton-Hunter reagent. (See, e.g., Bolton, A.E. and W.M. Hunter (1973) Biochem. J. 133:529-539.) Candidate molecules previously arrayed in the weUs of a multi-weU plate are incubated with the labeled OXRD, washed, and any weUs with labeled OXRD complex are assayed. Data obtained using different concentrations of OXRD are used to calculate values for the number, affinity, and association of OXRD with the candidate molecules. Alternatively, molecules interacting with OXRD are analyzed using the yeast two-hybrid system as described in Fields, S. and O. Song (1989) Nature 340:245-246, or using commerciaUy available kits based on the two-hybrid system, such as the MATCHMAKER system (Clontech).

OXRD may also be used in the PATHCALLING process (CuraGen Corp., New Haven CT) which employs the yeast two-hybrid system in a high-throughput manner to determine all interactions between the proteins encoded by two large Ubraries of genes (Nandabalan, K. et al. (2000) U.S. Patent No. 6,057,101).

XVII. Demonstration of OXRD Activity

Aldo/keto reductase activity of OXRD is proportional to the decrease in absorbance at 340 nm as NADPH is consumed (or increased absorbance if NADPH is produced, i.e., if the reverse reaction is monitored). A standard reaction mixture is 135 mM sodium phosphate buffer (pH 6.2-7.2 depending on enzyme), 0.2 mM NADPH, 0.3 M Uthium sulfate, 0.5-2.5 mg OXRD and an appropriate level of substrate. The reaction is incubated at 30°C and the reaction is monitored continuously with a spectiophotometer. OXRD activity is calculated as mol NADPH consumed / mg of OXRD. Alcohol dehydrogenase activity of OXRD is proportional to the increase in absorbance at 340 nm as NAD⁺ is reduced to NADH. A standard reaction mixture is 50 mM sodium phosphate, pH 7.5, and 0.25 mM EDTA. The reaction is incubated at 25 °C and monitored using a spectiophotometer. OXRD activity is calculated as mol NADH produced per mg of OXRD. Acyl-CoA dehydrogenase activity of OXRD is measured using an anaerobic electron transferring flavoprotein (ETF) assay. The reaction mixture comprises 50 mM Tris-HCl (pH 8.0), 0.5% glucose, and 50 μM acyl-CoA substrate (i.e., isovaleryl-CoA) that is pre-warmed to 32°C. The mixture is depleted of oxygen by repeated exposure to vacuum followed by layering with argon. Trace amounts of oxygen are removed by the addition of glucose oxidase and catalase foUowed by the addition of ETF to a final concentration of 1 μM. The reaction is initiated by addition of purified OXRD or a sample containing OXRD and exciting the reaction at 342 nm. Quenching of fluorescence caused by the transfer of electron from the substrate to ETF is monitored at 496 nm. 1 unit of acyl-CoA dehydrogenase activity is defined as the amount of OXRD required to reduce 1 μmol of ETF per minute (Reinard, T. et al. (2000) J. Biol. Chem. 275:33738-33743).

Alcohol dehydrogenase activity of OXRD is measured by foUowing the conversion of NAD⁺ to NADH at 340 nm (ε₃₄₀ = 6.22 mM"¹ cm^"1) at 25 °C in 0.1 M potassium phosphate (pH 7.5), 0.1 M glycine (pH 10.0), and 2.4 mM NAD⁺. Substrate (e.g., ethanol) and OXRD are then added to the reaction. The production of NADH results in an increase in absorbance at 340 nm and correlates with the oxidation of the alcohol substrate and the amount of alcohol dehydrogenase activity in the OXRD sample (Svensson, S. (1999) J. Biol Chem. 274:29712-29719).

Aldehyde dehydrogenase activity of OXRD is measured by determining the total hydrolase + dehydrogenase activity of OXRD and subtracting the hydrolase activity. Hydrolase activity is first determined in a reaction mixture containing 0.05 M Tris-HCl (pH 7.8), 100 mM 2-ME, and 0.5-18 μM substrate, e.g., 10-HCO-HPteGlu (10-formyltetrahydrofolate; HPteGlu, tetrahydrofolate) or

10-FDDF (10-formyl-5,8-dideazafolate). Approximately lμg of OXRD is added in a final volume of 1.0 ml. The reaction is monitored and read against a blank cuvette, containing aU components except enzyme. The appearance of product is measured at either 295 nm for 5,8-dideazafolate or 300 nm for HPteGlu using molar extinction coefficients of 1.89xl0⁴ and 2.17x10⁴ for 5,8-dideazafolate and HPteGlu, respectively. The addition of NADP⁺ to the reaction mixture aUows the measurement of both dehydrogenase and hydrolase activity (assays are performed as before). Based on the production of product in the presence of NADP⁺ and the production of product in the absence of the cof actor, aldehyde dehydrogenase activity is calculated for OXRD. In the alternative, aldehyde dehydrogenase activity is assayed using propanal as substrate. The reaction mixture contains 60 mM sodium pyrophosphate buffer (pH 8.5), 5 mM propanal, 1 mM NADP⁺, and OXRD in a total volume of 1 ml. Activity is determined by the increase in absorbance at 340 nm, resulting from the generation of NADPH, and is proportional to the aldehyde dehydrogenase activity in the sample (Krapenko, S.A. et al. (1995) J. Biol. Chem. 270:519-522). 6-phosphogluconate dehydrogenase activity of OXRD is measured by incubating purified OXRD, or a composition comprising OXRD, in 120 mM triethanolanime (pH 7.5), 0.1 mM EDTA, 0.5 mM NADP⁺, and 10-150 μM 6-phosphogluconate as substrate at 20-25 °C. The production of NADPH is measured fluorimetricaUy (340 nm excitation, 450 nm emission) and is indicative of 6-phosphogluconate dehydrogenase activity. Alternatively, the production of NADPH is measured photometricaUy, based on absorbance at 340 nm. The molar amount of NADPH produced in the reaction is proportional to the 6-phosphogluconate dehydrogenase activity in the sample (Tetaud, E. et al. (1999) Biochem. J. 338:55-60).

Ribonucleotide diphosphate reductase activity of OXRD is determined by incubating purified OXRD, or a composition comprising OXRD, along with dithiothreitol, Mg⁺⁺, and ADP, GDP, CDP, or UDP substrate. The product of the reaction, the corresponding deoxyribonucleotide, is separated from the substrate by thin-layer chromatography. The reaction products can be distinguished from the reactants based on rates of migration. The use of radiolabeled substrates is an alternative for increasing the sensitivity of the assay. The amount of deoxyribonucleotides produced in the reaction is proportional to the amount of ribonucleotide diphosphate reductase activity in the sample (note this is true only for pre-steady state kinetic analysis of ribonucleotide diphosphate reductase activity, as the enzyme is subject to negative feedback inhibition by products) (Nutter, L.M. and Y.-C Cheng (1984) Pharmac. Ther. 26:191-207).

Dihydrodiol dehydrogenase activity of OXRD is measured by incubating purified OXRD, or a composition comprising OXRD, in a reaction mixture comprising 50 mM glycine (pH 9.0), 2.3 mM NADP⁺, 8% DMSO, and a trans-dmydrodiol substrate, selected from the group including but not Umited to, (±)-trans-naphthalene-l,2-dihydrodiol (±)-trans-phenanthrene-l,2-dihydrodiol, and (±)- trans-chrysene-1 ,2-dmydrodiol The oxidation reaction is monitored at 340 nm to detect the formation of NADPH, which is indicative of the oxidation of the substrate. The reaction mixture can also be analyzed before and after the addition of OXRD by circular dichroism to determine the stereochemistry of the reaction components and determine which enantiomers of a racemic substrate composition are oxidized by the OXRD (Penning, T.M. (1993) Chemico-Biological Interactions 89:1- 34).

Glutathione S-transferase (GST) activity of OXRD is determined by measuring the OXRD catalyzed conjugation of GSH with l-chloro-2,4-dinitrobenzene (CDNB), a common substrate for most GSTs. OXRD is incubated with 1 mM CDNB and 2.5 mM GSH together in 0.1M potassium phosphate buffer, pH 6.5, at 25 °C The conjugation reaction is measured by the change in absorbance at 340 nm using an ultraviolet spectrophometer. OXRD activity is proportional to the change in absorbance at 340 nm.

15-oxoprostaglandin 13-reductase (PGR) activity of OXRD is measured foUowing the separation of contaminating 15-PGDH activity by DEAE chromatography. FoUowing isolation of

PGR containing fractions (or using the purified OXRD), activity is assayed in a reaction comprising 0.1 M sodium phosphate (pH 7.4), 1 mM 2-mercaptoethanol, 20 μg substrate (e.g., 15-oxo derivatives of prostaglandins PGE^ PGE₂, and PGE_2α), and 1 mM NADH (or a higher concentration of

NADPH). OXRD is added to the reaction which is then incubated for 10 min at 37 °C before termination by the addition of 0.25 ml 2 N NaOH. The amount of 15-oxo compound remaining in the sample is determined by measuring the maximum absorption at 500 nm of the terminated reaction and comparing this value to that of a terminated control reaction that received no OXRD. 1 unit of enzyme is defined as the amount required to catalyze the oxidation of 1 μmol substrate per minute and is proportional to the amount of PGR activity in the sample.

ChoUne dehydrogenase activity of OXRD is identified by the abiUty of E. coU, transformed with an OXRD expression vector, to grow on media containing choUne as the sole carbon and nitrogen source. The abiUty of the transformed bacteria to thrive is indicative of choUne dehydrogenase activity (Magne østeras, M. (1998) Proc. Natl. Acad. Sci. USA 95:11394-11399).

XVIII. Identification of OXRD Inhibitors

Compounds to be tested are arrayed in the weUs of a multi-well plate in varying concentrations along with an appropriate buffer and substrate, as described in the assays in Example XVJJ. OXRD activity is measured for each weU and the abiUty of each compound to inhibit OXRD activity can be determined, as weU as the dose-response profiles. This assay could also be used to identify molecules which enhance OXRD activity.

Various modifications and variations of the described methods and systems of the invention wiU be apparent to those skiUed in the art without departing from the scope and spirit of the invention. Although the invention has been described in connection with certain embodiments, it should be understood that the invention as claimed should not be unduly Umited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention which are obvious to those skiUed in molecular biology or related fields are intended to be within the scope of the foUowing claims. Table 1

Table 2

Table 3

Table 3 (cont.)

Table 4

Polynucleotide Sequence Fragments

SEQ ID NO:/

Incyte ID/

Sequence Length

4/72101285CB1/ 1-1527, 868-1691 897-1506, 902-1599, 905-1594, 996-1690, 1008-1561, 1010-1782, 1014-

1881 1617, 1031-1570, 1044-1633, 1053-1630, 1053-1645, 1058-1641, 1060-1703, 1072-1536, 1081-

1730, 1088-1156, 1103-1641, 1110-1653, 1113-1752, 1117-1641, 1123-1684, 1151-1580, 1152-

1591, 1153-1881, 1171-1850, 1186-1653, 1186-1844, 1188-1870, 1207-1881, 1218-1280, 1222-

1881, 1227-1736, 1227-1800, 1234-1506, 1243-1641, 1253-1879, 1257-1682, 1258-1524, 1269-

1509, 1272-1881, 1273-1753, 1275-1572, 1278-1508, 1278-1583, 1281-1879, 1285-1735, 1302-

1558, 1305-1879, 1308-1881, 1314-1591, 1317-1881, 1328-1601, 1335-1875, 1343-1582, 1346-

1881, 1353-1621, 1356-1605, 1363-1609, 1371-1690, 1377-1878, 1383-1595, 1406-1689, 1415-

1881, 1420-1613, 1537-1881

5/7481023CB1/ 1-1076, 1-1353

1353

6/2504257CB1/ 1-436 1-544, 139-563, 196- 801, 451-699, 451-963, 523-796, 523-1289, 714-1579, 933-1215,

1579 933-1492, 1-945

Table 5

o O

Table 6

o o

Table 7

Program Description Reference Parameter Threshold

ABI FACTURA A program that removes vector sequences and Applied Biosystems, Foster City, CA. masks ambiguous bases in nucleic acid sequences.

ABI/PARACEL EDF A Fast Data Finder useful in comparing and Applied Biosystems, Foster City, CA; Mismatch <50% annotating amino acid or nucleic acid sequences. Paracel Inc., Pasadena, CA.

ABI AutoAssembler A program that assembles nucleic acid sequences. Applied Biosystems, Foster City, CA.

BLAST A Basic Local Alignment Search Tool useful in Altschul, S.F. et al. (1990) J. Mol. Biol. ESTs: Probability value= 1.0E-8 sequence similarity search for amino acid and 215:403-410; Altschul, S.F. et al. (1997) or less nucleic acid sequences. BLAST includes five Nucleic Acids Res. 25:3389-3402. Full Length sequences: Probability functions: blastp, blastn, blastx, tblastn, and tblastx. value= l.OE-10 or less

FASTA A Pearson and Lipman algorithm that searches for Pearson, W.R. and D J. Lipman (1988) Proc. ESTs: fasta E value=1.06E-6 similarity between a query sequence and a group of Natl. Acad Sci. USA 85:2444-2448; Pearson, Assembled ESTs: fasta Identity= sequences of the same type. FASTA comprises as W.R. (1990) Methods Enzymol. 183:63-98; 95% or greater and least five functions: fasta, tfasta, fastx, tfastx, and and Smith, T.F. and M.S. Waterman (1981) Match length=200 bases or greater; ssearch. Adv. Appl. Math. 2:482-489. fastx E value=1.0E-8 or less

Full Length sequences: fastx score=100 or greater

BLIMPS A BLocks EMProved Searcher that matches a Henikoff, S. and J.G. Henikoff (1991) Nucleic Probability value= l.OE-3 or less sequence against those in BLOCKS, PRINTS, Acids Res. 19:6565-6572; Henikoff, J.G. and DOMO, PRODOM, and PFAM databases to search S. Henikoff (1996) Methods Enzymol. for gene families, sequence homology, and 266:88-105; and Attwood, T.K. et al. (1997) J. structural fingerprint regions. Chem. Inf. Comput. Sci. 37:417-424.

HMMER An algorithm for searching a query sequence against Krogh, A. et al. (1994) J. Mol. Biol. PFAM hits: Probability value= hidden Markov model (HMM)-based databases of 235:1501-1531; Sonnhammer, E.L.L. et al. l.OE-3 or less protein family consensus sequences, such as PFAM. (1988) Nucleic Acids Res. 26:320-322; Signal peptide hits: Score= 0 or Durbin, R. et al. (1998) Our World View, in a greater Nutshell, Cambridge Univ. Press, pp. 1-350.

Table 7 (cont.)

Program Description Reference Parameter Threshold

ProfileScan An algorithm that searches for structural and sequence Gribskov, M. et al. (1988) CABIOS 4:61-66; Normalized quality score≥GCG- motifs in protein sequences that match sequence patterns Gribskov, M. et al. (1989) Methods Enzymol. specified "HIGH" value for that defined in Prosite. 183:146-159; Bairoch, A. et al. (1997) particular Prosite motif. Nucleic Acids Res. 25:217-221. Generally, score=1.4-2.1.

Phred A base-calling algorithm that examines automated Ewing, B. et al. (1998) Genome Res. sequencer traces with high sensitivity and probability. 8:175-185; Ewing, B. and P. Green (1998) Genome Res. 8:186-194.

Phrap A Phils Revised Assembly Program including SWAT and Smith, T.F. and M.S. Waterman (1981) Adv. Score-- 120 or greater; CrossMatch, programs based on efficient implementation Appl. Math. 2:482-489; Smith, T.F. and M.S. Match length= 56 or greater of the Smith-Waterman algorithm, useful in searching Waterman (1981) J. Mol. Biol. 147:195-197; sequence homology and assembling DNA sequences. and Green, P., University of Washington, Seattle, WA.

Consed A graphical tool for viewing and editing Phrap Gordon, D. et al. (1998) Genome Res. 8:195-202. assemblies.

SPScan A weight matrix analysis program that scans protein Nielson, H. et al. (1997) Protein Engineering Score=3.5 or greater sequences for the presence of secretory signal peptides. 10:1-6; Claverie, J.M. and S. Audic (1997) CABIOS 12:431-439.

TMAP A program that uses weight matrices to delineate Persson, B. and P. Argos (1994) J. Mol. Biol. transmembrane segments on protein sequences and 237:182-192; Persson, B. and P. Argos (1996) determine orientation. Protein Sci. 5:363-371.

TMHMMER A program that uses a hidden Markov model (HMM) to Sonnhammer, E.L. et al. (1998) Proc. Sixth Intl. delineate transmembrane segments on protein sequences Conf. on Intelligent Systems for Mol. Biol., and determine orientation. Glasgow et al., eds., The Am. Assoc. for Artificial Intelligence Press, Menlo Park, CA, pp. 175-182.

Motifs A program that searches amino acid sequences for patterns Bairoch, A. et al. (1997) Nucleic Acids Res. 25:217-221; that matched those defined in Prosite. Wisconsin Package Program Manual, version 9, page M51-59, Genetics Computer Group, Madison, WI.

Claims

What is claimed is:

1. An isolated polypeptide selected from the group consisting of: a) a polypeptide comprising an amino acid sequence selected from the group consisting of SEQ ID NO:l-3, b) a polypeptide comprising a naturally occurring amino acid sequence at least 90% identical to an amino acid sequence selected from the group consisting of SEQ ID NO:l-3, c) a biologically active fragment of a polypeptide having an amino acid sequence selected from the group consisting of SEQ DO NO:l -3, and d) an immunogenic fragment of a polypeptide having an amino acid sequence selected from the group consisting of SEQ ID NO: 1-3.

2. An isolated polypeptide of claim 1 comprising an amino acid sequence selected from the group consisting of SEQ ID NO:l-3.

3. An isolated polynucleotide encoding a polypeptide of claim 1.

4. An isolated polynucleotide encoding a polypeptide of claim 2.

5. An isolated polynucleotide of claim 4 comprising a polynucleotide sequence selected from the group consisting of SEQ ID NO:4-6.

6. A recombinant polynucleotide comprising a promoter sequence operably linked to a polynucleotide of claim 3.

7. A cell transformed with a recombinant polynucleotide of claim 6.

8. A transgenic organism comprising a recombinant polynucleotide of claim 6.

9. A method of producing a polypeptide of claim 1, the method comprising: a) culturing a cell under conditions suitable for expression of the polypeptide, wherein said cell is transformed with a recombinant polynucleotide, and said recombinant polynucleotide comprises a promoter sequence operably linked to a polynucleotide encoding the polypeptide of claim 1 , and b) recovering the polypeptide so expressed.

10. A method of claim 9, wherein the polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 1-3.

11. An isolated antibody which specifically binds to a polypeptide of claim 1.

12. An isolated polynucleotide selected from the group consisting of: a) a polynucleotide comprising a polynucleotide sequence selected from the group consisting of SEQ ID NO:4-6, b) a polynucleotide comprising a naturally occurring polynucleotide sequence at least 90% identical to a polynucleotide sequence selected from the group consisting of SEQ ID NO:4-6, c) a polynucleotide complementary to a polynucleotide of a), d) a polynucleotide complementary to a polynucleotide of b), and e) an RNA equivalent of a) -d).

13. An isolated polynucleotide comprising at least 60 contiguous nucleotides of a polynucleotide of claim 12.

14. A method of detecting a target polynucleotide in a sample, said target polynucleotide having a sequence of a polynucleotide of claim 12, the method comprising: a) hybridizing the sample with a probe comprising at least 20 contiguous nucleotides comprising a sequence complementary to said target polynucleotide in the sample, and which probe specifically hybridizes to said target polynucleotide, under conditions whereby a hybridization complex is formed between said probe and said target polynucleotide or fragments thereof, and b) detecting the presence or absence of said hybridization complex, and, optionally, if present, the amount thereof.

15. A method of claim 14, wherein the probe comprises at least 60 contiguous nucleotides.

16. A method of detecting a target polynucleotide in a sample, said target polynucleotide having a sequence of a polynucleotide of claim 12, the method comprising: a) amplifying said target polynucleotide or fragment thereof using polymerase chain reaction amplification, and b) detecting the presence or absence of said amplified target polynucleotide or fragment thereof, and, optionally, if present, the amount thereof .

17. A composition comprising a polypeptide of claim 1 and a pharmaceutically acceptable excipient.

18. A composition of claim 17, wherein the polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 1-3.

19. A method for treating a disease or condition associated with decreased expression of functional OXRD, comprising administering to a patient in need of such treatment the composition of claim 17.

20. A method of screening a compound for effectiveness as an agonist of a polypeptide of claim 1, the method comprising: a) exposing a sample comprising a polypeptide of claim 1 to a compound, and b) detecting agonist activity in the sample.

21. A composition comprising an agonist compound identified by a method of claim 20 and a pharmaceutically acceptable excipient.

22. A method for treating a disease or condition associated with decreased expression of functional OXRD, comprising administering to a patient in need of such treatment a composition of claim 21.

23. A method of screening a compound for effectiveness as an antagonist of a polypeptide of claim 1, the method comprising: a) exposing a sample comprising a polypeptide of claim 1 to a compound, and b) detecting antagonist activity in the sample.

24. A composition comprising an antagonist compound identified by a method of claim 23 and a pharmaceutically acceptable excipient.

25. A method for treating a disease or condition associated with overexpression of functional OXRD, comprising administering to a patient in need of such treatment a composition of claim 24.

26. A method of screening for a compound that specifically binds to the polypeptide of claim 1, the method comprising: a) combining the polypeptide of claim 1 with at least one test compound under suitable conditions, and b) detecting binding of the polypeptide of claim 1 to the test compound, thereby identifying a compound that specifically binds to the polypeptide of claim 1.

27. A method of screening for a compound that modulates the activity of the polypeptide of claim 1 , the method comprising: a) combining the polypeptide of claim 1 with at least one test compound under conditions permissive for the activity of the polypeptide of claim 1, b) assessing the activity of the polypeptide of claim 1 in the presence of the test compound, and c) comparing the activity of the polypeptide of claim 1 in the presence of the test compound with the activity of the polypeptide of claim 1 in the absence of the test compound, wherein a change in the activity of the polypeptide of claim 1 in the presence of the test compound is indicative of a compound that modulates the activity of the polypeptide of claim 1.

28. A method of screening a compound for effectiveness in altering expression of a target polynucleotide, wherein said target polynucleotide comprises a sequence of claim 5, the method comprising: a) exposing a sample comprising the target polynucleotide to a compound, under conditions suitable for the expression of the target polynucleotide, b) detecting altered expression of the target polynucleotide, and c) comparing the expression of the target polynucleotide in the presence of varying amounts of the compound and in the absence of the compound.

29. A method of assessing toxicity of a test compound, the method comprising: a) treating a biological sample containing nucleic acids with the test compound, b) hybridizing the nucleic acids of the treated biological sample with a probe comprising at least 20 contiguous nucleotides of a polynucleotide of claim 12 under conditions whereby a specific hybridization complex is formed between said probe and a target polynucleotide in the biological sample, said target polynucleotide comprising a polynucleotide sequence of a polynucleotide of claim 12 or fragment thereof, c) quantifying the amount of hybridization complex, and d) comparing the amount of hybridization complex in the treated biological sample with the amount of hybridization complex in an untreated biological sample, wherein a difference in the amount of hybridization complex in the treated biological sample is indicative of toxicity of the test compound.

30. A diagnostic test for a condition or disease associated with the expression of OXRD in a biological sample, the method comprising: a) combining the biological sample with an antibody of claim 11 , under conditions suitable for the antibody to bind the polypeptide and form an antibody:polypeptide complex, and b) detecting the complex, wherein the presence of the complex correlates with the presence of the polypeptide in the biological sample.

31. The antibody of claim 11 , wherein the antibody is: a) a chimeric antibody, b) a single chain antibody, c) a Fab fragment, d) a F(ab')₂ fragment, or e) a humanized antibody.

32. A composition comprising an antibody of claim 11 and an acceptable excipient.

33. A method of diagnosing a condition or disease associated with the expression of OXRD in a subject, comprising administering to said subject an effective amount of the composition of claim

32.

34. A composition of claim 32, wherein the antibody is labeled.

35. A method of diagnosing a condition or disease associated with the expression of OXRD in a subject, comprising administering to said subject an effective amount of the composition of claim 34.

36. A method of preparing a polyclonal antibody with the specificity of the antibody of claim 11, the method comprising: a) immunizing an animal with a polypeptide consisting of an amino acid sequence selected from the group consisting of SEQ ID NO : 1 -3 , or an immunogenic fragment thereof, under conditions to elicit an antibody response, b) isolating antibodies from said animal, and c) screening the isolated antibodies with the polypeptide, thereby identifying a polyclonal antibody which binds specifically to a polypeptide comprising an amino acid sequence selected from the group consisting of SEQ ID NO : 1 -3.

37. A polyclonal antibody produced by a method of claim 36.

38. A composition comprising the polyclonal antibody of claim 37 and a suitable carrier.

39. A method of making a monoclonal antibody with the specificity of the antibody of claim 11, the method comprising: a) immunizing an animal with a polypeptide consisting of an amino acid sequence selected from the group consisting of SEQ ID NO: 1-3, or an immunogenic fragment thereof, under conditions to elicit an antibody response, b) isolating antibody producing cells from the animal, c) fusing the antibody producing cells with immortalized cells to form monoclonal antibody-producing hybridoma cells, d) culturing the hybridoma cells, and e) isolating from the culture monoclonal antibody which binds specifically to a polypeptide comprising an amino acid sequence selected from the group consisting of SEQ ID NO:l-3.

40. A monoclonal antibody produced by a method of claim 39.

41. A composition comprising the monoclonal antibody of claim 40 and a suitable carrier.

42. The antibody of claim 11 , wherein the antibody is produced by screening a Fab expression library.

43. The antibody of claim 11, wherein the antibody is produced by screening a recombinant immunoglobulin library.

44. A method of detecting a polypeptide comprising an amino acid sequence selected from the group consisting of SEQ ID NO:l-3 in a sample, the method comprising: a) incubating the antibody of claim 11 with a sample under conditions to allow specific binding of the antibody and the polypeptide, and b) detecting specific binding, wherein specific binding indicates the presence of a polypeptide comprising an amino acid sequence selected from the group consisting of SEQ ID NO:l-3 in the sample.

45. A method of purifying a polypeptide comprising an amino acid sequence selected from the group consisting of SEQ ID NO : 1 -3 from a sample, the method comprising: a) incubating the antibody of claim 11 with a sample under conditions to allow specific binding of the antibody and the polypeptide, and b) separating the antibody from the sample and obtaining the purified polypeptide comprising an amino acid sequence selected from the group consisting of SEQ ID NO:l-3.

46. A microarray wherein at least one element of the microarray is a polynucleotide of claim

13.

47. A method of generating an expression profile of a sample which contains polynucleotides, the method comprising: a) labeling the polynucleotides of the sample, b) contacting the elements of the microarray of claim 46 with the labeled polynucleotides of the sample under conditions suitable for the formation of a hybridization complex, and c) quantifying the expression of the polynucleotides in the sample.

48. An array comprising different nucleotide molecules affixed in distinct physical locations on a solid substrate, wherein at least one of said nucleotide molecules comprises a first oligonucleotide or polynucleotide sequence specifically hybridizable with at least 30 contiguous nucleotides of a target polynucleotide, and wherein said target polynucleotide is a polynucleotide of claim 12.

49. An array of claim 48, wherein said first oligonucleotide or polynucleotide sequence is completely complementary to at least 30 contiguous nucleotides of said target polynucleotide.

50. An array of claim 48, wherein said first oligonucleotide or polynucleotide sequence is completely complementary to at least 60 contiguous nucleotides of said target polynucleotide.

51. An array of claim 48, wherein said first oligonucleotide or polynucleotide sequence is completely complementary to said target polynucleotide.

52. An array of claim 48, which is a microarray.

53. An array of claim 48, further comprising said target polynucleotide hybridized to a nucleotide molecule comprising said first oligonucleotide or polynucleotide sequence.

54. An array of claim 48, wherein a linker joins at least one of said nucleotide molecules to said solid substrate.

55. An array of claim 48, wherein each distinct physical location on the substrate contains multiple nucleotide molecules, and the multiple nucleotide molecules at any single distinct physical location have the same sequence, and each distinct physical location on the substrate contains nucleotide molecules having a sequence which differs from the sequence of nucleotide molecules at another distinct physical location on the substrate.

56. A polypeptide of claim 1 , comprising the amino acid sequence of SEQ ID NO : 1.

57. A polypeptide of claim 1, comprising the amino acid sequence of SEQ ED NO:2.

58. A polypeptide of claim 1, comprising the amino acid sequence of SEQ ID NO:3.

59. A polynucleotide of claim 12, comprising the polynucleotide sequence of SEQ ID NO:4.

60. A polynucleotide of claim 12, comprising the polynucleotide sequence of SEQ ID NO:5.

61. A polynucleotide of claim 12, comprising the polynucleotide sequence of SEQ ED NO:6.

Ill