AU7478298A

AU7478298A - The use of a bone morphogenetic protein (bmp) receptor complex for screening

Info

Publication number: AU7478298A
Application number: AU74782/98A
Authority: AU
Inventors: Jan Susan Rosenbaum
Original assignee: Procter and Gamble Co
Current assignee: Procter and Gamble Co
Priority date: 1997-05-16
Filing date: 1998-05-13
Publication date: 1998-12-08
Also published as: CA2290755A1; JP2002510198A; IL132922A0; WO1998052038A1; EP0981745A1

Description

WU Y98/l2Uji PCT/US98/09519 1 THE USE OF A BONE MORPHOGENETIC PROTEIN (BMP) RECEPTOR COMPLEX FOR SCREENING TECHNICAL FIELD The present invention relates to the field of bone formation and development and cellular differentiation Specifically, the present invention relates to the use of a type II receptor that is shared between activins and bone morphogenetic proteins, together with a bone morphogenetic protein type I receptor, for screening cellular differentiation actives. The invention further relates to cells co-transfected with DNA coding for this receptor and DNA coding for a type I bone morphogenetic protein receptor. BACKGROUND Humans and other warm-blooded animals can be afflicted by a number of bone-related disorders. Such disorders range from bone fractures, to debilitating diseases such as osteoporosis. While in healthy individuals bone growth generally proceeds normally and fractures heal without the need for pharmacological intervention, in certain instances bones may become weakened or may fail to heal properly. For example, healing may proceed slowly in the elderly and in patients undergoing treatment with corticosteroids (e.g., transplant patients). Osteoporosis is a condition in which bone hard tissue is lost disproportionately to the development of new hard tissue. Osteoporosis can generally be defined as the reduction in the quantity of bone, or the atrophy of skeletal tissue; marrow and bone spaces become larger, fibrous binding decreases, and compact bone becomes fragile. Another bone related disorder is osteoarthritis, which is a disorder of the movable joints WO 9N/52038 PCT/US98/09519 2 characterized by deterioration and abrasion of articular cartilage, as well as by formation of new bone at the joint surface. While a variety of treatments are available for such bone-related disorders, none of the treatments provide optimum results. One of the difficulties facing individuals who treat bone-related disorders is a lack of complete understanding of bone metabolism and of the bone-related disorders. A key to such understanding is identifying and characterizing each of the components involved in bone growth. Bone morphogenetic proteins (BMPs) have been demonstrated to play a role in bone formation and development (J. M. Wozney, Molec. Reproduct. and Develop., 32: 160-167 (1992); B.L.M Hogan, Genes & Dev. 10: 1580-1594 (1996)). Furthermore, the role of BMPs may not be limited to their role in bone. The finding that the BMPs are found at significant concentrations in other tissues such as brain, kidney, stratified squamous epithelia, and hair follicle (N.A. Wall, M. Blessing, C.V.E. Wright, and B.L.M. Hogan, I. Cell Biol., 120: 493-502 (1993); E. Ozkaynak, P.N.J. Schnegelsberg, D.F. Jin, G.M. Clifford, F.D. Warren, E.A. Drier, and H. Oppermann, J Biol. Chem., 267: 25220-25227 (1992); K.M. Lyons, C.M. Jones, and B.L.M. Hogan, Trends in Genetics, 7: 408-412 (1991); V. Drozdoff, N.A. Wall, and W.J. Pledger, Proceedings of the National. Academy of Sciences, U.S.A., 91: 5528-5532 (1994)) suggests that they may play additional roles in development and differentiation. In support of this, BMPs have recently been found to promote nerve cell differentiation, to affect hair follicle formation, and have been implicated in cardiac and kidney development as well as the development of a variety of other organs (K. Basler, T. Edlund, T.M. Jessell, and T. Yamada, Cell, 73: 687-702 (1993); V.M. Paralkar, B.S. Weeks, Y.M. Yu, H.K. Kleinman, and A.H. Reddi, J. Cell Biol., 119: 1721-1728 (1992); M. Blessing, L.B. Nanney, L.E. King, C.M. Jones, and B.L. Hogan, Genes Dev., 7: 204-215 (1993); A.T. Dudley, K.M. Lyons, and E.J. Robertson, Genes & Dev. 9:2795-2807(1995); G.C. Luo, A.L.J.J. Hofmann, M. Bronckers, A. Sohocki, A. Bradley, and G. Karsenty, Genes WO 98/52038 PCT/US98/09519 3 & Dev. 9:2808-2820(1995); T.M. Schultheiss, J.B.E. Burch, and A.B. Lasser, Genes & Dev. 11:451-462 (1997). B.L.M Hogan, Genes & Dev. 10: 1580-1594 (1996)). A BMP initiates its biological effect on cells by binding to a specific BMP receptor expressed on the plasma membrane of a BMP-responsive cell. A receptor is a protein, usually spanning the cell membrane, which binds to a ligand from outside the cell, and as a result of that binding sends a signal to the inside of the cell which alters cellular function. In this case, the ligand is the protein BMP, and the signal induces the cellular differentiation. Because of the ability of a BMP receptor to specifically bind BMPs, purified BMP receptor compositions are useful in diagnostic assays for BMPs, as well as in raising antibodies to the BMP receptor for use in diagnosis and therapy. In addition, purified soluble BMP receptor compositions may be used directly in therapy to bind or scavenge BMPs, thereby providing a means for regulating the activities of BMPs in bone and other tissues. In order to study the structural and biological characteristics of BMP receptors and the role played by BMPs in the responses of various cell populations to BMPs during tissue growth/formation stimulation, or to use a BMP receptor effectively in therapy, diagnosis, or assay, purified compositions of BMP receptor are needed. Such compositions, however, are obtainable in practical yields only by cloning and expressing genes encoding the receptors using recombinant DNA technology. Efforts to purify BMP receptors for use in biochemical analysis or to clone and express mammalian genes encoding BMP receptors have been impeded by lack of a suitable source of receptor protein or mRNA. Prior to the present invention, few cell lines were known to express high levels of high affinity BMP receptors consisting of the receptor subunits described herein, which precluded purification of the receptor for protein sequencing or construction of genetic libraries for direct expression cloning. Availability of the BMP receptor sequence will make it possible to generate cell lines with high levels WO 98/52038 PCT/US98/09519 4 of recombinant BMP receptor for biochemical analysis and use in screening experiments. The BMPs are members of the TGF-p superfamily. Other members of the TGF-P3 superfamily include TGF-P3, activins, inhibins, Millerian Inhibiting Substance, and the Growth and Differentiation Factors (GDFs) (B.L.M Hogan, Genes & Dev. 10: 1580-1594 (1996)). As expected, the receptors for various members of the TGF-P3 superfamily share similar structural features. Receptors of the TGF-3 ligand superfamily are typically classified into one of two sub-groups, designated as type I and type II. The type I and type II receptors are classified as such based on amino acid sequence characteristics. Both the type I and type II receptors possess a relatively small extracellular ligand binding domain, a transmembrane region, and an intracellular protein kinase domain that is predicted to have serine/threonine kinase activity (Lin and Moustakas, Cellular and Molecular Biology, 40: 337-349 (1994); L.S. Mathews, Endocrine Reviews, 15: 310-325 (1994); L. Attisano, J.L. Wrana, F. L6pez-Casillas, and J. Massagu6, Biochimica et Biophysica Acta, 1222: 71-80 (1994); P. Ten Dijke, K. Miyazono, and C.-H. Heldin, Current Opinion in Cell Biology 8:139-145 (1996), H. Yamashita, P. Ten Dijke, C.-H. Heldin, and K. Miyazono, Bone 19:569-574 (1996), J. Massagu6, F. Weis-Garcia, Cancer Surveys 27: 41-64 (1996)) The type I receptors cloned to date belong to a distinct family whose kinase domains are highly related and share > 85% sequence similarity (B.B. Koenig et al., Molecular and Cellular Biology, 14: 5961-5974 (1994)). The intracellular juxtamembrane region of the type I receptors is characterized by an SGSGSG motif 35-40 amino acids from the transmembrane region, and the carboxy terminus of these receptors is extremely short (B.B. Koenig et al., Molecular and Cellular Biology, 14: 5961-5974 (1994); L. Attisano, J.L. Wrana, F. L6pez-Casillas, and J. Massagu6, Biochimica et Biophysica Acta, 1222: 71-80 (1994)). The extracellular domain of the type I receptors contains a characteristic cluster of cysteine residues, WO 98/52038 PCT/US98/09519 5 termed the "cysteine box", located within 25-30 amino acids of the transmembrane region, and another cluster of cysteine residues, termed the "upstream cysteine box", located after the putative signal sequence (B. B. Koenig, et al., Molecular and Cellular Biology, 14: 5961-5974 (1994); L. Attisano, et al., Biochimica et Biophysica Acta, 1222: 71-80 (1994); J. Massagu6, F. Weis-Garcia, Cancer Surveys 27: 41-64 (1996)). Three distinct mammalian type I receptors have been reported for the BMPs: Bone Morphogenetic Protein Receptor Kinase-1 (herein referred to as "BRK-1") (see U.S.S.N. 08/158,735, filed November 24, 1993 by J. S. Cook, et al.; and B.B. Koenig et al., Molecular and Cellular Biology, 14: 5961-5974 (1994)), ALK-2, and ALK-6. BRK-1 is the mouse homologue of human ALK-3, and is also known as BMPR-IA or TFR-11 (see P. Ten Dijke, K. Miyazono, and C.-H. Heldin, Current Opinion in Cell Biology 8:139-145 (1996)); the rat homologue of BRK-1 has also been cloned (K. Takeda, S. Oida, H. Ichijo, T. limura, Y. Marnoka, T. Amagasa and S. Sasaki, Biochemical and Biophysical Research Communications, 204: 203-209 (1994)). BRK-1 has been shown to bind both BMP-2 and BMP-4 more efficiently than it binds BMP-7, as measured by affinity labeling (J.M. Graff, R.S. Thies, J.J. Song, A.J. Celeste, and D.A. Melton, Cell 79:169-179 (1994); B.B. Koenig et al., Molecular and Cellular Biology, 14: 5961-5974 (1994); A. Suzuki, R.S. Thies, N. Yamaji, J.J. Song, J. M. Wozney K. Murakami, and N. Ueno, Proceedings of the National Academy of Sciences, U.S.A., 91:10255-10259 (1994); P. ten Dijke, H. Yamashita, T.K. Sampath, A.H. Reddi, M. Estevez, D. L. Riddle, H. Ichijo, C.-H. Heldin, and K. Miyazono, J. Biological Chemistry 269:16985-16988 (1994)), whereas it does not bind GDF-5 at all (H. Nishitoh, H. Ichijo, M. Kimura, T. Matsumoto, F. Makishima, A. Yamaguchi, H. Yamashita, S. Enomoto, and K. Miyazono, J. Biological Chemistry 271:21345-21352 (1996)). The binding properties of ALK-6, also known as BMPR-IB (see P. Ten Dijke, K. Miyazono, and C.-H. Heldin, Current Opinion in Cell Biology 8:139-145 (1996)) are similar to that WU 9WUis~ PCT/US98/09519 6 of BRK-1, except that ALK-6 is also capable of binding GDF-5 (P. ten Dijke, H. Yamashita, T.K. Sampath, A.H. Reddi, M. Estevez, D. L. Riddle, H. Ichijo, C.-H. Heldin, and K. Miyazono, J. Biological Chemistry 269:16985-16988 (1994); H. Nishitoh, H. Ichijo, M. Kimura, T. Matsumoto, F. Makishima, A. Yamaguchi, H. Yamashita, S. Enomoto, and K. Miyazono, J. Biological Chemistry 271:21345 21352 (1996)). It is also postulated that ALK-6 is the mouse homologue of the chicken receptor Bone Morphogenetic Protein Receptor Kinase-2 (herein referred to as "BRK-2") (also referred to as RPK-1) (S. Sumitomo, T. Saito, and T. Nohno, DNA Sequence, 3: 297-302 (1993)). ALK-2, also known as ActRI, Tsk7L, or SKR1 (see P. Ten Dijke, K. Miyazono, and C.-H. Heldin, Current Opinion in Cell Biology 8:139-145 (1996)); K. Matsuzaki, J. Xu, F. Wang, W.L. McKeehan, L. Krummen, and M. Kan, J. Biological Chemistry 268:12719-12723 (1993)) binds BMP-7 but does not bind BMP-4 or GDF-5 (K. Matsuzaki, J. Xu, F. Wang, W.L. McKeehan, L. Krummen, and M. Kan, J. Biological Chemistry 268:12719-12723 (1993); H. Nishitoh, H. Ichijo, M. Kimura, T. Matsumoto, F. Makishima, A. Yamaguchi, H. Yamashita, S. Enomoto, and K. Miyazono, J. Biological Chemistry 271:21345-21352 (1996); P. ten Dijke, H. Yamashita, T.K. Sampath, A.H. Reddi, M. Estevez, D. L. Riddle, H. Ichijo, C.-H. Heldin, and K. Miyazono, J. Biological Chemistry 269:16985-16988 (1994)). In contrast to the type I receptors, the kinase domains of the type II receptors are only distantly related to one another. The SGSGSG motif found in type I receptors is not found in type II receptors. Also, the "upstream cysteine box" of type I receptors is not present in type II receptors. Furthermore, while all of the activin type II receptors contain a proline-rich sequence motif in the intracellular juxtamembrane region, there is no characteristic sequence motif that is common to all type II receptors (L.S. Mathews, Endocrine Reviews, 15: 310-325 (1994)). The length of the carboxy terminus of the type II receptors is considerably variable, with the longest known carboxy terminus being found in the nematode BMP type II WO 98/52038 PCT/US98/09519 7 receptor DAF-4 (M. Estevez, L. Attisano, J.L. Wrana, P.S. Albert, J. Massagu6, and D.L. Riddle, Nature, 365: 644-49 (1993)) that was cloned from C. elegans, and the mammalian BMP-specific type II receptor BRK-3 described in U. S. Patent application serial number 08/334,179 by Rosenbaum and Nohno, incorporated herein by reference, also known as BMP-RII (B.L. Rosenzweig, T. Imamura, T. Okadome, G.N. Cox, H. Yamashita, P. Ten Dijke, C.-H. Heldin, and K. Miyazono, Proceedings of the National Academy of Sciences, US.A., 92: 7632-7636 (1995); T. Nohno, T. Ishikawa, T. Saito, K. Hosokawa, S. Noji, D.H. Wolsing, and J. S. Rosenbaum, J. Biological Chemistry 270:22522-22526 (1995), F. Liu, F. Ventura, J. Doody, and J. Massagu6, Molecular and Cellular Biology, 15: 3479-3486 (1995)). The extracellular domain of the type II receptors contains a single cysteine box located near the transmembrane region. Aside from the presence of the cysteine box, there is little sequence similarity amongst the extracellular domains of the type II receptors for TGF-P3, activin, and BMPs. Signaling by members of the TGF-p ligand superfamily requires the presence of both type I and type II receptors on the surface of the same cell (L.S. Mathews, Endocrine Reviews, 15: 310-325 (1994); L. Attisano, J.L. Wrana, F. L6pez-Casillas, and J. Massagu6, Biochimica et Biophysica Acta, 1222: 71-80 (1994); P. Ten Dijke, K. Miyazono, and C.-H. Heldin, Current Opinion in Cell Biology 8:139-145 (1996), H. Yamashita, P. Ten Dijke, C.-H. Heldin, and K. Miyazono, Bone 19:569-574 (1996), J. Massagu6, F. Weis-Garcia, Cancer Surveys 27: 41-64 (1996)). Similar to what has been demonstrated for the TGF-P and activin receptor systems (for reviews see (T. Brand and M.D. Schneider, Circulation Research 78:173-179 (1996); P. Ten Dijke, K. Miyazono, and C.-H. Heldin, Current Opinion in Cell Biology 8:139-145 (1996)), BMPs bind to a heteromeric receptor complex consisting of a type I (B.B. Koenig et al., Molecular and Cellular Biology, 14: 5961-5974 (1994); P. ten Dijke, H. Yamashita, T.K. Sampath, A.H. Reddi, M. Estevez, D. L. Riddle, H. Ichijo, C.-H. Heldin, and K. Miyazono, J.

WO 98/52038 PCT/US98/09519 8 Biological Chemistry 269:16985-16988 (1994)) and a type II (B.L. Rosenzweig, T. Imamura, T. Okadome, G.N. Cox, H. Yamashita, P. Ten Dijke, C.-H. Heldin, and K. Miyazono, Proceedings of the National Academy of Sciences, US.A., 92: 7632 7636 (1995); T. Nohno, T. Ishikawa, T. Saito, K. Hosokawa, S. Noji, D.H. Wolsing, and J. S. Rosenbaum, J. Biological Chemistry 270:22522-22526 (1995), F. Liu, F. Ventura, J. Doody, and J. Massagu6, Molecular and Cellular Biology, 15: 3479-3486 (1995); A. Letsou, K. Arora, J.L. Wrana, K. Simin, V. Twombly, J. Jamal, K. Staehling-Hampton, F.M. Hoffmann, W.M. Gelbart, J. Massagu6, and M.B. O'Connor, Cell 80:899-908 (1995); E. Ruberte, T. Marty, D. Nellen, M. Affolter, and K. Basler, Cell 80:889-897(1995); H. Yamashita, P. ten Dijke, D. Huylebroeck, T.K. Sampath, M. Andries, J.C. Smith, C.-H. Heldin, and K. Miyazono, J. Cell Biology 130:217-226 (1995)) receptor, and BMP-mediated signaling requires the presence of both the type I and type II receptors (F. Liu, F. Ventura, J. Doody, and J. Massagu6, Molecular and Cellular Biology, 15: 3479 3486 (1995); B.L. Rosenzweig, T. Imamura, T. Okadome, G.N. Cox, H. Yamashita, P. Ten Dijke, C.-H. Heldin, and K. Miyazono, Proceedings of the National Academy of Sciences, US.A., 92: 7632-7636 (1995); E. Ruberte, T. Marty, D. Nellen, M. Affolter, and K. Basler, Cell 80:889-897(1995); H. Yamashita, P. ten Dijke, D. Huylebroeck, T.K. Sampath, M. Andries, J.C. Smith, C.-H. Heldin, and K. Miyazono, J. Cell Biology 130:217-226 (1995) P.A. Hoodless, T. Haerry, S. Abdollah, M. Stapleton, M.B. O'Connor, L. Attisano, and J.L. Wrana, Cell 85: 489 500 (1996)). Unlike the TGF-P3 (L. Attisano, J. Circamo, F. Ventura, F.M.B. Weis, J. Massagu6, and J.L. Wrana, Cell 75:671-680 (1993); R. Ebner, R.-H. Chen, S. Lawler, T. Zioncheck, and R. Derynck, Science 262:900-902 (1993); P. Franz6n, P. ten Dijke, H. Ichijo, H. Yamashita, P. Schulz, C.-H. Heldin, and K. Miyazono, Cell 75:681-692 (1993)) and activin (J. Circamo, F.M.B. Weis, F. Ventura, R. Wieser, J.L. Wrana, L. Attisano, and J. Massagu6, Molecular and Cellular Biology WO 98/52038 PCT/US98/09519 9 14:3810-3821 (1994); R. Ebner, R.-H. Chen, S. Lawler, T. Zioncheck, and R. Derynck, Science 262:900-902 (1993)) type I receptors, the type I receptors for BMPs are capable of binding ligand on their own when expressed in COS cells (J.M. Graff, R.S. Thies, J.J. Song, A.J. Celeste, and D.A. Melton, Cell 79:169-179 (1994); (B.B. Koenig et al., Molecular and Cellular Biology, 14: 5961-5974 (1994); A. Suzuki, R.S. Thies, N. Yamaji, J.J. Song, J. M. Wozney K. Murakami, and N. Ueno, Proceedings of the National Academy of Sciences, U.S.A., 91:10255-10259 (1994); P. ten Dijke, H. Yamashita, T.K. Sampath, A.H. Reddi, M. Estevez, D. L. Riddle, H. Ichijo, C.-H. Heldin, and K. Miyazono, J. Biological Chemistry 269:16985-16988 (1994)), although binding affinity and/or crosslinking efficiency to the type I receptor is enhanced in the presence of the type II receptor (A. Letsou, K. Arora, J.L. Wrana, K. Simin, V. Twombly, J. Jamal, K. Staehling-Hampton, F.M. Hoffmann, W.M. Gelbart, J. Massagu6, and M.B. O'Connor, Cell 80:899-908 (1995); F. Liu, F. Ventura, J. Doody, and J. Massagu6, Molecular and Cellular Biology, 15: 3479-3486 (1995); T. Nohno, T. Ishikawa, T. Saito, K. Hosokawa, S. Noji, D.H. Wolsing, and J. S. Rosenbaum, J. Biological Chemistry 270:22522 22526 (1995); B.L. Rosenzweig, T. Imamura, T. Okadome, G.N. Cox, H. Yamashita, P. Ten Dijke, C.-H. Heldin, and K. Miyazono, Proceedings of the National Academy of Sciences, U.S.A., 92: 7632-7636 (1995); H. Yamashita, P. ten Dijke, D. Huylebroeck, T.K. Sampath, M. Andries, J.C. Smith, C.-H. Heldin, and K. Miyazono, J. Cell Biology 130:217-226 (1995)). In further contrast to the TGF-p and activin receptor systems, crosslinking of BMP-2 or BMP-4 to the mammalian BMP type II receptor BRK-3 is not detectable in the absence of the type I receptor, and only a very low level of binding is detectable at the whole cell level in cells transfected with the type II receptor alone (T. Nohno, T. Ishikawa, T. Saito, K. Hosokawa, S. Noji, D.H. Wolsing, and J. S. Rosenbaum, J. Biological Chemistry 270:22522-22526 (1995)). Together, these data imply that, while BMPs might possibly bind to either subunit alone, high affinity binding and signaling are only WO 98/52038 PCT/US98/09519 10 obtained when the appropriate heteromeric receptor complex is formed, and the differences in sequence of the various type II receptor cytoplasmic domains suggests that unique signaling receptor complexes will be produced by ligand binding to different type I: type II receptor subunit combinations. Hence, there is a need for identification of high affinity mammalian type I: type II BMP receptor complexes in addition to the type I receptor and type II receptor complexes that have already been identified, if one is to use these receptor complexes in screening assays for the identification of novel cellular differentiation agents that act through an interaction with high affinity BMP receptor complexes. We have previously reported the use of the type II BMP receptor kinase protein BRK-3 which enables the formation of a signaling complex with a BMP type I receptor, as described in U. S. Patent application serial number 08/462,467 by Rosenbaum, incorporated herein by reference, and we have previously reported that the BRK-2 type I receptor forms a high affinity complex with BRK-3, whereas this is not the case when BRK-1 is the type I receptor (T. Nohno, T. Ishikawa, T. Saito, K. Hosokawa, S. Noji, D.H. Wolsing, and J. S. Rosenbaum, J. Biological Chemistry 270:22522-22526 (1995)). This implies that additional mammalian high affinity BMP receptor complexes exist in which a type II receptor other than BRK-3 forms a complex with BRK-1 in response to BMP-2 and BMP-4 ligands. In the fruit fly Drosophila melanogaster the product of the 25D/Tkv locus is the fly homologue of mammalian BRK-1 and BRK-2 that is capable of binding the Drosophila homologue of BMP-2 and BMP-4, the product of the decapentaplegic (Dpp) gene, as well as the mammalian BMP-2 (H. Okano, S. Yoshikawa, A. Suzuki, N. Ueno, M. Kaizu, M. Okabe, T. Takahashi, M. Matsumoto, K. Sawamoto, and K. Mikoshiba, Gene 148: 203-209 (1994); A. Pelton, Y. Chen, K. Staehling-Hampton, J.L. Wrana, L. Attisano, J. Szidonya, J. A. Cassill, J. Massagu6, and F.M. Hoffmann, Cell 78: 239-250 (1994)). The product of the Drosophila punt gene product, which was originally identified as an activin type II/type IIB receptor wo 98/52038 PCT/US98/09519 11 homologue (S.R. Childs, J.L. Wrana, K.Arora, L. Attisano, M.B. O'Connor, and J. Massagu6, Proceedings of the National Academy ofSciences, US.A., 90: 9475-9479 (1993)), is required in concert with the Tkv receptor in order for Dpp to signal; implying that Tkv and Punt form a signaling receptor complex in the presence of Dpp ligand (D. Nellen, R. Burke, G. Struhl, and K. Basler, Cell 85: 357-368 (1996); E. Ruberte, T. Marty, D. Nellen, M. Affolter, and K. Basler, Cell 80:889 897(1995); A. Letsou, K. Arora, J.L. Wrana, K. Simin, V. Twombly, J. Jamal, K. Staehling-Hampton, F.M. Hoffmann, W.M. Gelbart, J. Massagu6, and M.B. O'Connor, Cell 80:899-908 (1995)). The mammalian activin type II receptor has been reported to bind BMP-7 with high affinity and to signal in concert with the ALK-2 or BRK-2 type I receptors, but a signal was not produced when BRK-1 was the type I receptor, suggesting that mammalian ActRII and BRK-1 do not form a signaling receptor complex (H. Yamashita, P. ten Dijke, D. Huylebroeck, T.K. Sampath, M. Andries, J.C. Smith, C.-H. Heldin, and K. Miyazono, J. Cell Biology 130:217-226 (1995)). The ActRIIB receptor exists in four distinct splice variants, described as ActRIIB 1 , ActRIIB 2 , ActRIIB 3 , and ActRIIB 4 , each of which is capable of binding activin ligand (L. Attisano, J.L. Wrana, S. Cheifetz, and J. Massagu6, Cell 68: 97 108 (1992)). We demonstrate here that there is an absolute requirement for the eight amino acids only present in the extracellular juxtamembrane region of ActRIIB 1 and ActRIIB 2 in order for this type II receptor to bind BMP-2 and BMP-4 ligands and to form a complex with BMP type I receptors BRK-1 and BRK-2 in the presence of BMP-4 or BMP-2 ligands. We further demonstrate that the BRK-1 + ActRIIB 2 complex binds BMP-4 ligand with higher affinity than does the BRK-1 type I receptor alone, indicating that the BRK-1 + ActRIIB 2 complex represents a high affinity complex for BMP-4, analagous to what is observed with the BRK-2 + BRK-3 BMP receptor complex (T. Nohno, T. Ishikawa, T. Saito, K. Hosokawa, S. Noji, D.H. Wolsing, and J. S. Rosenbaum, J. Biological Chemistry 270:22522- WO 98/52U38 PCT/US98/09519 12 22526 (1995)), and that the BRK-1 + ActRIIB 2 complex therefore represents a distinct high affinity BMP receptor complex. Finally, we demonstrate that the BRK-1 + ActRIIB 2 complex, described in detail below, is competent for signaling a response to BMPs. ActRIIB 2 and ActRIIB 1 therefore can be used as BMP type II receptors in concert with mammalian BMP type I receptors in order to identify novel compounds which interact with this BMP receptor complex and to determine if these novel compounds behave as BMP receptor agonists or antagonists which will be useful as therapeutic agents in humans and other mammals. OBJECTS OF THE PRESENT INVENTION It is an object of the present invention to provide a method for identifying compounds capable of binding to a BMP receptor kinase protein complex. It is also an object of the present invention to provide a method for determining the amount of a compound capable of binding a BMP receptor kinase protein complex in a sample. It is also an object of the present invention to provide a host cell comprising a recombinant expression vector encoding a BMP type II receptor kinase protein and a recombinant expression vector encoding a BMP type I receptor kinase protein comprising said BMP receptor kinase protein complex. It is also an object of the present invention to provide a method for determining whether a test compound produces a signal upon binding to a BMP receptor protein complex. SUMMARY The present invention relates to a method for determining whether a compound is capable of binding to a BMP receptor kinase protein complex, the method comprising introducing a sample comprising the compound to the BMP receptor kinase protein complex and allowing the compound to bind to the BMP receptor kinase protein complex, wherein the BMP receptor kinase protein complex is comprised of a BMP type I receptor kinase protein and the BMP/Activin type II WO 98/52038 PCT/US98/09519 13 receptor kinase protein, comprising the eight amino acid juxtamembrane region, which is characteristic of ActRIIBI or ActRIIB 2 . The invention further relates to a method for determining the concentration of a BMP receptor ligand in a clinical sample, the method comprising introducing the sample comprising the ligand to a BMP receptor kinase protein complex and allowing the ligand to bind to the BMP receptor kinase protein complex, wherein the BMP receptor kinase protein complex is comprised of a BMP type I receptor kinase protein and BMP/Activin type II receptor kinase protein, ActRIIB 1 or ActRIIB 2 . The invention further relates to a host cell co-transfected with an expression vector comprising a DNA sequence that codes for the BMP/Activin type II receptor kinase protein ActRIIB 2 and an expression vector comprising a DNA sequence that codes for a BMP type I receptor kinase protein. The invention further relates to a host cell co-transfected with an expression vector comprising a DNA sequence that codes for a soluble BMP type I receptor kinase protein and a soluble BMP/Activin type II receptor kinase protein ActRIIB 2 . The invention further relates to a method for determining a test compound produces a signal upon binding to a BMP receptor protein complex, the method comprising: (a) transfecting BMP receptor protein complex expressing cells with a 3TP-Lux luciferase reporter gene (J.L. Wrana, L. Attisano, J. Carcamo, A. Zentella, J. Doody, M. Laiho, X.-F. Wang, and J. Massagu6, Cell 71:1003-1014 (1992)) in conjunction with a beta-galactosidase gene, wherein the cells have been transfected with a DNA sequence coding for BMP receptor kinase protein ActRIIBi 1 or ActRIIB 2 and a DNA sequence coding for a BMP type I receptor kinase protein; (b) culturing (i) a first set of the cells in the presence of the test compound, and (ii) a second set of the cells in the absence of the test compound; (c) quantitating via the arbitrary light units the level of luciferase activity produced by activation of the WO 98/5203h PCT/US98/09519 14 luciferase enzyme that results from stimulation of the reporter construct produced from step (b); and (d) comparing the amount of arbitrary light units quantitated in step (c) from the first set of cells to the amount of arbitrary light units quantitated in step (c) for the second set of cells. DESCRIPTION The present invention answers the need for a method for determining whether a compound has BMP receptor affinity. The method comprises introducing a sample comprising a test compound to a BMP receptor kinase protein complex and allowing the compound to bind to the BMP receptor kinase protein complex, wherein the receptor complex comprises a BMP type I receptor kinase protein and the BMP/Activin type II receptor kinase protein, generally refered to as ActRIIB, with anspecific eight amino acid juxtamembrane region, characteristic of a protein designated herein as "ActRIIB2". The invention also answers the need for a host cell that is co-transfected with an expression vector comprising a DNA sequence that codes for BMP/Activin type II receptor kinase protein ActRIIB 2 and an expression vector comprising a DNA sequence that codes for a BMP type I receptor kinase protein. Also provided is a method for determining the concentration of a BMP receptor ligand in a clinical sample, the method comprising introducing the sample comprising the ligand to a BMP receptor kinase protein complex and allowing the ligand to bind to the receptor complex, wherein the receptor complex is comprised of a BMP type I receptor kinase protein and BMP receptor kinase protein ActRIIB 2 . The invention also answers the need for a host cell that is co transfected with an expression vector comprising a DNA sequence that codes for a soluble BMP/Activin type II receptor kinase protein ActRIIB 2 and an expression vector comprising a DNA sequence that codes for a soluble BMP type I receptor kinase protein. As used herein, "mouse ActRIIB 2 " means a protein having the amino acid sequence SEQ ID NO:4, as well as proteins having amino acid sequences WO 98/52038 PCT/US98/09519 15 substantially similar to SEQ ID NO:4, and which are biologically active in that they are capable of binding a BMP molecule (including, but not limited to BMP-2, BMP 4, and/or BMP-7), or transducing a biological signal initiated by a BMP molecule binding to a cell, or crossreacting with antibodies raised against ActRIIB 2 protein, or peptides derived from the protein sequence of ActRIIB 2 , or forming a complex with a BMP type I receptor, or co-immunoprecipitating with a BMP type I receptor when antibodies specific for either ActRIIB 2 or a BMP type I receptor are used. As used herein, "mouse BMP receptor kinase protein" or "m-BRK-3" means a protein having amino acid sequence SEQ ID NO:12 or a sequence substantially similar to that sequence. Also included in this definition are proteins of this ilk which are biologically active in that they are capable of binding a BMP molecule (including, but not limited to BMP-2, BMP-4, and/or BMP-7), or transducing a biological signal initiated by a BMP molecule binding to a cell, or crossreacting with antibodies raised against this protein, or peptides derived from the protein sequence of this protein, or forming a complex with a BMP type I receptor, or co immunoprecipitating with a BMP type I receptor when antibodies specific for either this protein or a BMP type I receptor are used. As used herein, "BMP receptor kinase protein BRK-3" or "BRK-3" refers individually and collectively to the receptor proteins h-BRK-3 (SEQ ID NO:10), and m-BRK-3 (and soluble and incomplete fragments of any of these). Also included in this definition are proteins of this ilk which are biologically active in that they are capable of binding a BMP molecule (including, but not limited to BMP-2, BMP-4, and/or BMP-7), or transducing a biological signal initiated by a BMP molecule binding to a cell, or crossreacting with antibodies raised against this protein, or peptides derived from the protein sequence of this protein, or forming a complex with a BMP type I receptor, or co-immunoprecipitating with a BMP type I receptor when antibodies specific for either this protein or a BMP type I receptor are used. Also included are BMP receptor kinase proteins substantially similar to hwo l 9S/IU.1 PCT/US98/09519 16 BRK-3 and m-BRK-3 (and soluble and incomplete fragments as above). Such receptor proteins, DNA sequences coding for the proteins, and recombinant expression vectors comprising said DNA are described and claimed in U. S. Patent application serial number 08/462,467 by Rosenbaum, incorporated herein by reference. As used herein, a "BMP Type I Receptor Kinase" is a protein capable of binding BMP-2, BMP-4 and/or other known BMPs, and bears sequence characteristics of a type I receptor including, but not limited to, an extracellular ligand binding domain containing a cysteine box and an upstream cysteine box, an SGSGSG motif, designated the GS domain, in the intracellular juxtamembrane region, an intracellular kinase domain that is greater than about 85% similar to other type I receptors for other ligands in the TGF-p superfamily, and/or a relatively short carboxy terminus. As used herein, "BMP Type I Receptor Kinase" also includes receptor proteins having the characteristics of a BMP type I receptor as described in the literature, such as in: B.B. Koenig et al., Molecular and Cellular Biology, 14: 5961-5974 (1994); L. Attisano, et al., Biochimica et Biophysica Acta, 1222: 71-80 (1994); J. Massagu6, L. Attisano, and J. L. Wrana, Trends in Cell Biology, 4: 172 178 (1994); and ten Dijke, et al., J. Biological Chemistry, 269: 16985-16988 (1994). Examples of BMP type I receptors include, but are not limited to: BRK-1 (B.B. Koenig et al., Molecular and Cellular Biology, 14: 5961-5974 (1994), the rat homologue of which is BMPR-Ia (K. Takeda, S. Oida, H. Ichijo, T. limura, Y. Maruoka, T. Amagasa, and S. Sasaki, Biochem. Biophys. Res. Communica., 204: 203-209 (1994)); BRK-2, also referred to as RPK-1 (S. Sumitomo, T. Saito, and T. Nohno, DNA Sequence, 3: 297-302 (1993), and postulated to be the chicken homologue of ALK-6 (P. ten Dijke, H. Yamashita, H. Ichijo, P. Franz6n, M. Laiho, K. Miyazono, and C.-H. Heldin, Science, 264: 101-104 (1994)); ALK-2, which has been shown to be a receptor for BMP-7 (ten Dijke et al., J. Biological Chemistry, 269: 16985-16988 (1994)); the Xenopus BMP type I receptor that binds BMP-2 and WO 98/5207.8 PCT/US98/09519 17 BMP-4 and which is involved in mesoderm induction (J.M. Graff, R.S. Thies, J.J. Song, A.J. Celeste, and D.A. Melton, Cell, 79: 169-179 (1994)); and type I receptors from Drosophila that bind the decapentaplegic peptide, which is the Drosophila homologue of BMP-2 and BMP-4. These Drosophila receptors are designated 25D1, 25D2, and 43E (T. Xie, A.L. Finelli, and R.W. Padgett, Science, 263: 1756-1759 (1994); A. Penton, Y. Chen, K. Staehling-Hampton, J. L. Wrana, L. Attisano, J. Szidonya, J. A. Cassill, J. Massagu6, and F.M. Hoffmann, Cell, 78: 239 250 (1994); and T. J. Brummel, V. Twombly, G. Marqu6s, J. L. Wrana, S. J. Newfeld, L. Attisano, J. Massagu6, M. B. O'Connor, and W. M. Gelbart, Cell, 78: 251-261 (1994)). Preferred BMP type I receptors useful in the present invention include, but are not limited to, polypeptides having the amino acid sequences substantially similar to SEQ ID NO:14 (BRK-1), SEQ ID NO:16 (BRK-2). As used herein, "soluble fragment" refers to an amino acid sequence corresponding to the extracellular region of BRK-1, BRK-2, or the ActRIIB, preferably Act RIIB 1 or ActRIIB 2 , which is capable of binding BMPs. Soluble fragments include the complete extracellular domain of the receptor protein, prior to the start of the predicted transmembrane region. Examples of such soluble fragments for ActRIIB2 include, but are not limited to, polypeptides having the amino acid sequences substantially similar to SEQ ID NO:4, wherein amino acids 1-134 are present. Examples of such soluble fragments for ActRIIB2 include, but are not limited to, polypeptides having the amino acid sequences substantially similar to SEQ ID NO:4, wherein amino acids 1-134 are present. It is understood from these examples that by homology one can determine the essential and non-essential region, given these examples. Examples of soluble fragments for BRK-1 include, but are not limited to, polypeptides having the amino acid sequences substantially similar to amino acid residues 1-153 in SEQ ID NO:14.

WO 98/52038 PCT/US98/09519 18 Examples of soluble fragments for BRK-2 include, but are not limited to, polypeptides having the amino acid sequences substantially similar to amino acid residues 1-126 in SEQ ID NO:16. As used herein, "incomplete receptor kinase fragment" refers to an amino acid sequence corresponding to the extracellular, transmembrane, and intracellular juxtamembrane region of BRK-1, BRK-2, or the ActRIIB, preferably ActRIIB 1 or ActRIIB 2 , which is capable of binding BMPs in a manner similar to the full-length receptor, but which is incapable of signaling due to deletion of the intracellular kinase domain (otherwise known as a dominant negative receptor construct). Examples of such incomplete receptor fragments for ActRIIB 2 include, but are not limited to, polypeptides having the amino acid sequences substantially similar to SEQ ID NO:4; wherein amino acids 1-161 are present and amino acids 162-191 are optionally present, for ActRIIB 1 , with amino acid sequences substantially similar to SEQ ID NO:2, amino acids 1-161 are present and amino acids 162-215 are optionally present. Examples of incomplete receptor fragments for BRK-1 include, but are not limited to, polypeptides having the amino acid sequences substantially similar to SEQ ID NO:14; wherein amino acids 1-177 are present and amino acids 178-229 are optionally present. Examples of incomplete receptor fragments for BRK-2 include, but are not limited to, polypeptides having the amino acid sequences substantially similar to SEQ ID NO:16; wherein amino acids 1-149 are present and amino acids 150-199 are optionally present As used herein, a "BMP receptor kinase protein complex" is the combination of a BMP type I receptor and BMP receptor kinase protein ActRIIB 2 . The combination of the type I and ActRIIB 2 receptors includes, but is not limited to, a combination of the type I and ActRIIB 2 receptors in solution (e.g., as soluble fragments); a combination of the receptors (e.g., as soluble fragments) attached to a WO 98/52038 PCT/US98/09519 19 solid support; or a combination of the receptors (e.g., as full-length or incomplete fragments) within a cell membrane of transfected cells. As used herein, "substantially similar" when used to define either amino acid or nucleic acid sequences, means that a particular subject sequence, for example, a sequence altered by mutagenesis, varies from a reference sequence by one or more substitutions, deletions, or additions, the net effect of which is to retain biological activity of the ActRIIB 2 protein. Alternatively, nucleic acid sequences and analogs are "substantially similar" to the specific DNA sequence disclosed herein if the DNA sequences, as a result of degeneracy in the genetic code, encode an amino acid sequence substantially similar to the reference amino acid sequence. In addition, "substantially similar" means a receptor protein that will react with antibodies generated against the ActRIIB 2 protein or peptides derived from the protein sequence of ActRIIB 2 . "Homologues" are proteins that maintain the similar function and have substantially the same amino acid chain as those proteins listed in the sequence listings, however there may be innocuous substitutions in the chain that would not alter structure or function, for example, one hydrophobic amino acid for another, e.g., leucine for isoleucine; or an acidic amino acid for another, such as glutamic acid for aspartic acid, and the like. As such these proteins include whole proteins with at least 90% homology as understood by the art, with deletions and/or insertions or fragments thereof. For example, a rat protein which is 95% homologous to that of a human based on the peptide sequence derived from the DNA or cDNA sequence, and a similarly derived bovine protein with the same function and similar homology, are both considered homologues. Thus homologous cDNAs cloned from other organisms give rise to homologous proteins. Likewise proteins may be considered homologues based on the amino acid sequence alone. Practical limitations of amino acid sequencing would allow one to determine that a protein is homologous to another using for example comparison of wu W95aiSa8 PCTIUS98/09519 20 the first 50 amino acids of the protein. Hence 90% homology in would allow for 5 differing amino acids in the chain of the first 50 amino acids of the homologous protein. In addition, it is acknowledged that certain proteins have regions that are important to their function that are evolutionarily conserved. Such areas, may render the protein homologous. Thus the term "homologous" can be defined in terms of function or structure. Evidence of this evolutionary conservation is found in the group of proteins making up the complex. For example, type II receptors for members of the TGF-3 superfamily. When expressed in COS cells, this human type II receptor is capable of forming differential heteromeric complexes with either the murine BRK-1 or the chicken BRK-2 type I receptors in the presence of BMP-4. It has been demonstrated previously that murine and human BMP type I receptors form a complex with the nematode DAF-4 type II receptor (see Koenig, B. B., Cook, J.S., Wolsing, D.H., Ting, J., Tiesman, J.P., Correa, P.E., Olson, C.A., Pecquet, A.L., Ventura, F., Grant, R.A., Chen, G.-X., Wrana, J.L., Massagu6, J., and Rosenbaum, J.S., Mol. Cell. Biol., Vol. 14, pp. 5961-5974 (1994); and ten Dijke, P., Yamashita, H., Sampath, T.K., Reddi, A.H., Estevez, M., Riddle, D.L., Ichijo, H., Heldin, C.-H., and Miyazono, K., J. Biol. Chem., Vol. 269, pp. 16985-16988 (1994)), that a dominant negative construct of the murine BMP type I receptor BMPR-IA/TFR 11/BRK-1 alters dorsal-ventral patterning when expressed in ventral blastomeres of Xenopus embryos (see Suzuki, A., Thies, R.S., Yamaji, N., Song, J.J., Wozney, J.M., Murakami, K., and Ueno, N., Proc. Natl. Acad Sci. US.A., Vol. 91, pp. 10255-10259 (1994)), that the chicken BMP-related ligand dorsalin-1 induces alkaline phosphatase activity in murine bone marrow stromal cells (see Basler, K., Edlund, T., Jessell, T.M., and Yamada, T. Cell, Vol. 73, pp. 687-702 (1993)), and that the Drosophila BMP-2 and BMP-7 homologues, Dpp and 60A, induce ectopic bone formation in rats (see Sampath, T.K., Rashka, K.E., Doctor, J.S., Tucker, R.F., and Hoffmann, F.M., Proc. Natl. Acad. Sci. US.A., Vol. 90, pp.

WO 98/520us PCT/US98/09519 21 6004-6008 (1993)). Given the high degree of sequence conservation among the proteins of this family, it is unlikely that the observed differential binding properties for the type I-type II receptor complexes previously described herein (T. Nohno, T. Ishikawa, T. Saito, K. Hosokawa, S. Noji, D.H. Wolsing, and J. S. Rosenbaum, J. Biological Chemistry 270:22522-22526 (1995)) are due to the species differences of the type I receptors but are, rather, due to the unique nature of individual type I:type II receptor complexes. These homologous proteins, whether from nematode, chicken, frog, or mammal are all contemplated in this invention. Mere allelic or interspecies variations do not appear to be significant enough to distinguish between such variations. Without being bound by theory, the differential binding properties described below most likely reflect the different signaling potential of the receptor complexes upon ligand binding. (see Circamo, J., Weis, F.M.B., Ventura, F., Wieser, R., Wrana, J.L., Attisano, L., and Massagu6, J., Mol. Cell. Biol., Vol. 14, pp. 3810-3821 (1994)). The skilled artisan will appreciate that the degeneracy of the genetic code provides for differing DNA sequences to provide the same transcript, and thus the same peptide. In certain cases preparing the DNA sequence, which encodes for the same peptide, but differs from the native DNA include; --- ease of sequencing or synthesis; --- increased expression of the peptide; and --- preference of certain heterologous hosts for certain codons over others. These practical considerations are widely known and provide embodiments that may be advantageous to the user of the invention. Thus it is clearly contemplated that the native DNA, or DNA listed in the SEQ ID listed here, or incorporated by reference, are not the only embodiment or the DNA envisioned in this invention. As used herein, "biologically active" means that a particular molecule shares sufficient amino acid sequence similarity with the embodiments of the present WO 98/52038 PCT/US98/09519 22 invention disclosed herein to be capable of binding detectable quantities of BMP-2 or BMP-4, or transmitting a BMP-2 or BMP-4 stimulus to a cell, for example, as a component of a hybrid receptor construct. Preferably, a biologically active BMP type I receptor: ActRIIB 2 receptor complex within the scope of the present invention means the receptor protein kinase complex is capable of binding [125I] BMP-4 with nanomolar or subnanomolar affinity (Kd approximately equal to 10 9 M). Preferably, the affinity is from about lxl0-10M to lx10- 9 M, with a proportion of binding sites exhibiting a Kd less than 10- 9 M. As used herein, "signal" or "signaling" refers to a biological response caused by some external stimulus, preferably related to binding of a molecule, including a small molecule, peptide or the like, that may be detected if instrumentation is sensitive enough and the correct parameter is measured. Examples of signaling include, the agonism or antagonism of an enzyme, the triggering or inhibition of a biochemical cascade, or the like. As used herein, "operably linked" refers to a condition in which portions of a linear DNA sequence are capable of influencing the activity of other portions of the same linear DNA sequence. For example, DNA for a signal peptide (secretory leader) is operably linked to DNA for a polypeptide if it is expressed as a precursor which participates in the secretion of the polypeptide; a promoter is operably linked to a coding sequence if it controls the transcription of the sequence; or a ribosome binding site is operably linked to a coding sequence if it is positioned so as to permit translation. Generally, operably linked means contiguous and, in the case of secretory leaders, contiguous in reading frame. The skilled artisan will appreciate that the particular use of the DNA, whether it be to transfect a cell, perform site directed mutagenesis or some other use will determine how DNA sequences are used and how they are operably linked. This is well within the scope of the skilled artisan to determine.

WO 98/52038 PCT/US98/09519 23 As used herein, "ATCC" means American Type Culture Collection, Rockville, Maryland. As used herein, "bone morphogenetic protein 2" or "BMP-2" means a peptide encoded by a DNA sequence contained in ATCC No. 40345 (see ATCC/NIH REPOSITORY CATALOGUE OF HUMAN AND MOUSE DNA PROBES AND LIBRARIES, sixth Edition, 1992, p. 57, hereinafter "ATCC/NIH REPOSITORY CATALOGUE"). Isolation of BMP-2 is disclosed in U.S. Patent No. 5,013,649, Wang, Wozney and Rosen, issued May 7, 1991; U.S. Patent No. 5,166,058, Wang, Wozney and Rosen, issued November 24, 1992; and U.S. Patent No. 5,168,050, Hammonds and Mason, issued December 1, 1992; each of which is incorporated herein by reference. As used herein, "bone morphogenetic protein 4" or "BMP-4" means a peptide encoded by a DNA sequence contained in ATCC No. 40342 (see ATCC/NIH REPOSITORY CATALOGUE). Isolation of BMP-4 is disclosed in U.S. Patent No. 5,013,649, Wang, Wozney and Rosen, issued May 7, 1991, incorporated herein by reference. As used herein, "bone morphogenetic protein 7" or "BMP-7" means a peptide encoded by a DNA sequence contained in ATCC No. 68020 and ATT 68182 (see ATCC/NIH Repository Catalogue), where the cDNA in ATCC 68182 is claimed to contain all of the nucleotide sequences necessary to encode BMP-7 proteins. Isolation of BMP-7 is disclosed in U S. Patent 5,141,905, issued August 25, 1992, to Rosen, et al., which is incorporated herein by reference. As used herein, "DNA sequence" refers to a DNA polymer, in the form of a separate fragment or as a component of a larger DNA construct, which has been derived from DNA isolated at least once in substantially pure form, i.e., free of contaminating endogenous materials and in a quantity or concentration enabling identification, manipulation, and recovery of the sequence and its component nucleotide sequences by standard biochemical methods, for example, using a WO 98/52038 PCT/US98/09519 24 cloning vector. Such sequences are preferably provided in the form of an open reading frame uninterrupted by internal nontranslated sequences (introns) which are typically present in eukaryotic genes. Genomic DNA containing the relevant sequences could also be used. Sequences of non-translated DNA may be present 5' or 3' from the open reading frame, where the same do not interfere with manipulation or expression of the coding regions. DNA sequences encoding the proteins provided by this invention can be assembled from cDNA fragments and short oligonucleotide linkers, or from a series of oligonucleotides, to provide a synthetic gene which is capable of being expressed in a recombinant transcriptional unit. As used herein, "recombinant" means that a protein is derived from a DNA sequence which has been manipulated in vitro and introduced into a host organism. Such an organism may produce the protein naturally, or may be devoid of any mechanism for making the protein initially: preferably the host organism does not produce the protein in its normal state and hence is a "heterologous host." Recombinant proteins can be made using bacterial, fungal (e.g., yeast), or insect expression systems. As used herein, "recombinant expression vector" refers to a DNA construct used to express DNA which encodes a desired protein (for example, ActRIIB 2 ) and which includes a transcriptional subunit comprising an assembly of 1) genetic elements having a regulatory role in gene expression, for example, promoters and enhancers, 2) a structural or coding sequence which is transcribed into mRNA and translated into protein, and 3) appropriate transcription and translation initiation and termination sequences. Using methodology well known in the art, recombinant expression vectors of the present invention can be constructed. Possible vectors for use in the present invention include, but are not limited to: for mammalian cells, pJT4 or pJT6 (discussed further below), pcDNA-1 (Invitrogen, San Diego, Ca) and pSV-SPORT 1 (Gibco-BRL, Gaithersburg, MD); for insect cells, pBlueBac III or WO 98/52038 PCT/US98/09519 25 pBlueBacHis baculovirus vectors (Invitrogen, San Diego, CA); and for bacterial cells, pET-3 (Novagen, Madison, WI). The DNA sequence coding for a ActRIIB 2 protein receptor kinase of the present invention can be present in the vector operably linked to regulatory elements. The present invention relates to a host cell co-transfected with an expression vector comprising a DNA sequence that codes for BMP receptor kinase protein ActRIIB 2 and an expression vector comprising a DNA sequence that codes for a BMP type I receptor kinase protein. In one embodiment, the expression vector for the mouse ActRIIB 2 protein comprises a DNA sequence coding for the mouse ActRIIB 2 receptor protein, or a soluble or incomplete fragment thereof. (The DNA can be genomic or cDNA.) Preferably the mouse ActRIIB 2 protein is coded for by the nucleic acid sequence SEQ ID NO:3. In a preferred embodiment of the present invention, the host cells of the present invention are co-transfected with the plasmid construct pJT6-mActRIIB 2 and the plasmid construct pJT4-Jl59F (for BRK-1) or plasmid construct pJT3 BRK-2 (for BRK-2), thereby resulting in co-expression of mActRIIB 2 and BRK-1, or mActRIIB 2 and BRK-2, respectively. Transfection with the recombinant molecules can be effected using methods well known in the art. As used herein, "host cell" means a cell comprising a recombinant expression vector described herein. Host cells may be stably transfected or transiently transfected within a recombinant expression plasmid or infected by a recombinant virus vector. The host cells include prokaryotic cells, such as Escherichia coli, fungal systems such as Saccharomyces cerevisiae, permanent cell lines derived from insects such as Sf-9 and Sf-21, and permanent mammalian cell lines such as Chinese hamster ovary (CHO) and SV40-transformed African green monkey kidney cells (COS). In one embodiment, the present invention relates to a method that is useful for identifying compounds capable of binding to a BMP receptor kinase protein. In WO 98/52J038 PCT/US98/09519 26 another embodiment, the invention relates to a method that is useful for determining the concentration of a BMP receptor ligand (e.g., BMP-2, BMP-4, or BMP-7, or another as-yet identified BMP receptor ligand) in a clinical sample. In each of these methods, a sample comprising a putative ligand or a known ligand is introduced to a BMP receptor kinase protein complex, wherein the receptor complex is comprised of a BMP type I receptor kinase protein and BMP receptor kinase protein ActRIIB 2 . Preferably, the ActRIIB 2 receptor kinase protein is m-ActRIIB 2 , having an amino acid sequence SEQ ID NO:4, or the soluble fragment thereof or the incomplete fragment thereof. For example, BMP concentration in a sample can be determined by radioreceptor assay, in which unlabeled BMP in the sample competes with labeled tracer BMP for binding to the ActRIIB 2 + BMP type I receptor complex. As the amount of BMP in the sample increases, it reduces the amount of labeled BMP which is able to bind to the receptor protein complex comprising ActRIIB 2 and the type I receptor. Comparison with a standard curve prepared with known concentrations of unlabeled BMP allows accurate quantitation of BMP concentration in the sample. Labeling of tracer BMP is preferably done by iodination with [1 2 5 1]Nal. ActRIIB 2 can be expressed in the outer membrane of a stable cell line which also expresses the BMP type I receptor kinase, or supplied as a soluble fragment in solution with a soluble type I receptor fragment, or as a soluble fragment covalently attached to a solid support in conjunction with a type I receptor covalently attached to a solid support. To perform the assay, unlabeled BMP from the sample and labeled tracer BMP compete for binding to the receptor until equilibrium is reached. The receptor-BMP complex is then isolated from free ligand, for example by washing (in the case of an adherent cell line), rapid filtration or centrifugation (in the case of a nonadherent cell line or receptor bound to a solid support), or precipitation of the receptor-ligand complex with antibodies, polyethylene glycol, or other precipitating agent followed by filtration or centrifugation (in the case of a WO 98/52038 PCT/US98/09519 27 soluble receptor). The amount of labeled BMP in the complex is then quantitated, typically by gamma counting, and compared to known standards. These methods have been described in the literature using other receptors (M. Williams, Med Res. Rev., 11:147-184 (1991); M. Higuchi and B.B. Aggarwal, Anal. Biochem., 204: 53 58 (1992); M.J. Cain, R.K. Garlick and P.M. Sweetman, J Cardiovasc. Pharm., 17: S150-S151 (1991); each of which are incorporated herein by reference), and are readily adapted to the present BMP type I receptor: ActRIIB 2 receptor/BMP system. Such a radioreceptor assay can be used for diagnostic purposes for quantitation of BMP in clinical samples, where such quantitation is necessary. The methods of the present invention is also useful in high-throughput screens to identify compounds capable of binding to ActRIIB 2 , or a homologous receptor protein, that is complexed to a BMP type I receptor kinase protein. In such a method, the higher the affinity of the compound for the ActRIIB 2 /type I complex, the more efficiently it will compete with the tracer for binding to the complex, and the lower the counts in the receptor-ligand complex. In this case, one compares a series of compounds within the same concentration range to see which competed for receptor binding with the highest affinity. This invention is useful for determining whether a ligand, such as a known or putative drug, is capable of binding to and/or activating the receptors encoded by the DNA molecules of the present invention. Transfection of said DNA sequence into the cell systems described herein provides an assay system for the ability of ligands to bind to and/or activate the receptor complex encoded by the isolated DNA molecules. Recombinant cell lines, such as those described herein, are useful as living cell cultures for competitive binding assays between known or candidate drugs and ligands which bind to the receptor and which are labeled by radioactive, spectroscopic or other reagents. Membrane preparations containing the receptor isolated from transfected cells are also useful for competitive binding assays. Soluble receptors derived from the ligand binding domain of the receptor can also WO 98/52038 PCT/US98/09519 28 be employed in high-throughput screening of drug candidates. Functional assays of intracellular signaling can act as assays for binding affinity and efficacy in the activation of receptor function. In addition, the recombinant cell lines may be modified to include a reporter gene operably linked to a response element such that a signal sent by the receptor turns on the reporter gene. Such a system is especially useful in high throughput screens directed at identification of receptor agonists. These recombinant cell lines constitute "drug discovery systems", useful for the identification of natural or synthetic compounds with potential for drug development. Such identified compounds could be further modified or used directly as therapeutic compounds to activate or inhibit the natural functions of the receptor encoded by the isolated DNA molecule. The soluble receptor protein complex of the present invention can be administered in a clinical setting using methods such as by intraperitoneal, intramuscular, intravenous, or subcutaneous injection, implant or transdermal modes of administration, and the like. Such administration can be expected to provide therapeutic alteration of the activity of the BMPs. SEQ ID NO:3 and SEQ ID NO:7 represent the DNA sequences coding for m-ActRIIB 2 and mActRIIB 4 receptor proteins, respectively, that were isolated from mouse hair/skin samples. These sequences could be readily used to obtain the cDNA for ActRIIB 2 or ActRIIB 4 from other species, including, but not limited to, human, rat, rabbit, Drosophila, and Xenopus. The present invention further relates to a method for determining whether a test compound produces a signal upon binding to a BMP receptor protein complex. Such a method comprises employing the BMP receptor protein complex in a transcriptional reporter assay. The method for determining whether a test compound produces a signal upon binding to the BMP receptor protein complex comprises (a) transfecting BMP receptor protein complex expressing cells with a 3TP-Lux luciferase reporter gene (J.L. Wrana, L. Attisano, J. Circamo, A. Zentella, J. Doody, wo 98/52U35 PCT/US98/09519 29 M. Laiho, X.-F. Wang, and J. Massagu6, Cell 71:1003-1014 (1992)) in conjunction with a beta-galactosidase gene, wherein the cells have been transfected with a DNA sequence coding for BMP receptor kinase protein ActRIIB 1 or ActRIIB 2 and a DNA sequence coding for a BMP type I receptor kinase protein; (b) culturing (i) a first set of the cells in the presence of the test compound, and (ii) a second set of the cells in the absence of the test compound; (c) quantitating via the arbitrary light units the level of luciferase activity produced by activation of the luciferase enzyme that results from stimulation of the reporter construct produced from step (b); and (d) comparing the amount of arbitrary light units quantitated in step (c) from the first set of cells to the amount of arbitrary light units quantitated in step (c) for the second set of cells. In addition, this same type of assay may be done using autoradiography. It will be apparent to the skilled artisan that a method for determining whether a test compound produces a signal upon binding to the BMP receptor portion complex comprises (a) labeling BMP receptor protein complex expressing cells with 3 2 P, wherein the cells have been transfected with a DNA sequence coding for BMP receptor kinase protein ActRIIB 1 or ActRIIB 2 and a DNA sequence coding for a BMP type I receptor kinase protein; (b) culturing (i) a first set of the cells in the presence of the test compound, and (ii) a second set of the cells in the absence of the test compound; (c) quantitating via autoradiography any phosphorylated proteins produced from step (b); and (d) comparing the amount of phosphorylated proteins quantitated in step (c) from the first set of cells to the amount of phosphorylated proteins quantitated in step (c) for the second set of cells. For purposes of illustrating a preferred embodiment of the present invention, the following non-limiting examples are discussed in detail. Example 1 Isolation of Mouse ActRIIB ndB A PCR probe is generated from degenerate primers JT65 (SEQ ID NO: 17) and JT69 (SEQ ID NO:18) from conserved protein sequences in kinase domain II (JT65) WU 98/52U3i PCT/US98/09519 30 and in kinase domain VIII (JT69) of the known receptor serine/threonine kinases. This probe was subcloned into pBLUESCRIPT vector (Stratagene, La Jolla, CA) to give pBS2-54 and used to screen against a NIH3T3 library, which has been previously described in U. S. Patent application serial number 08/462,467 by Rosenbaum, incorporated herein by reference. A partial ActRIIB clone (38-4-2) which contains approximately 2.3 kb of the ActRIIB sequence is isolated. In order to isolate the full-length mouse homologue of ActRIIB, a cDNA library is constructed from mouse hair/skin tissues (E82 strain, 2 days after hair shaving). Total RNA (1.8 mg) is isolated from the cells using a Total RNA Separator Kit (Clontech, Palo Alto, CA). Messenger RNA (6.3 jig) is isolated from this total RNA (1 mg) using the mRNA Separator Kit (Clontech, Palo Alto, CA). An aliquot of the mRNA (2 pg) is used to make cDNA library using the SUPER SCRIPT Plasmid System for cDNA Synthesis and Plasmid Cloning (Life Technologies, Gaithersburg, MD) according to the manufacturer's instructions. The resulting library contains approximately 500,000 primary colonies, and is divided into 72 pools, each containing 7,000 colonies. The initial screen of the library is accomplished by PCR. Plasmids used as templete are purified from each of the 72 pools, using QIAGEN columns (Qiagen, Chatsworth, CA). Positive pools are identified by PCR with primers designed to amplify all ActRIIB isoforms as described previously (Tsung-Chieh, J.Wu, M.H. Jih, L. Wang, and Y.-J. Y. Wan, Molecular Reproduction and Development 38: 9-15 (1994)); these primers are provided herein and referenced as ActRIIBTF (SEQ ID NO: 19) and ActRIIBTR (SEQ ID NO:20). The PCR reaction was performed using the GENE-AMP PCR Kit with AMPLITAQ DNA Polymerase (Perkin Elmer, Applied Biosystems, Foster City, CA). An initial melting period at 94 0 C for 5 min was followed by 30 cycles of the following program: melting at 94oC for 1 min, annealing at 55 0 C for 1 min, and extension at 72oC for 1 min.

wu wi/~iosU PCT/US98/09519 31 For secondary screening, plates are streaked with the E. coli stocks from three positive pools (2,000 colonies/plate). A HYBOND nylon membrane is placed on top of the plate so that the bacterial colonies are transferred to the filter. The colonies are then allowed to recover at 37 0 C for 2-3 hr. The filter is soaked in 10% SDS for 3 min, then transferred to 1.5 M NaCI, 0.5 M NaOH for 5 min, neutralized in 1.5 M NaC1, 0.5 M Tris, pH 7.5 for 5 min, and washed in 3X SSC. To remove proteins, the blots are then shaken with 50 pg/ml of proteinase K (Boehringer Mannheim, Indianapolis, IN) in 0.1 M Tris, pH 7.6, 10 mM EDTA, 0.15 M NaC1, 0.02% SDS at 55 0 C for 1 hr. The mouse partial ActRIIB cDNA isolated from NIH3T3 library (clone 38-4-2) is cut with Mlu I and to give a 2.3 kb fragment. The fragment is randomly labeled with ot-[ 3 2 P]-dCTP having a specific activity of 3000 Ci/mmol (NEN Research Products, Boston, MA), using a PRIME-IT II Random Primer Labeling Kit (Stratagene, La Jolla, CA; a kit for random primer labeling of DNA, including Klenow DNA polymerase, primers, and buffers). The labeled probe is allowed to hybridize to the filters for 18 hr at 42 0 C in hybridization buffer (Sigma, St. Louis, MO) consisting of 50% deionized formamide, 5 X SSPE (lx SSPE = 0.14 M NaC1, 8 mM sodium phosphate, 0.08 mM EDTA, pH 7.7), 1X Denhardt's solutions, and 100 pg/ml of denatured salmon testis DNA. The blot is then washed in 0.25X SSPE, 0.5% sodium dodecyl sulfate (SDS), two times at 25oC for 15 min each, then two times at 65 0 C for 30 min each. The blot is then exposed to Kodak X-OMAT AR autoradiography film for 18 hr at -80 0 C. Colonies which corresponded to labeled spots on the autoradiograph are streaked on plates for tertiary screening, which is performed exactly as described above for secondary screening. Three positive clones are isolated. The inserts from the 3 positive clones are sequenced using the TAQ DYE DEOXY Terminator Cycle Sequencing Kit and an Applied Biosystems Model 373A Automated DNA Sequencer. Comparison of the sequences shows that clone A46 3/pSPORT contains the complete coding of the ActRIIB 4 variant whereas clone A49wo W~i/ania PCT/US98/09519 32 8/pSPORT aligns with the ActRIIB 2 variant approximately 50 base pairs from the beginning of the coding region (see Example 2 below). Example 2 ActRIIB 2 and ActRIIB4 Sequence Analysis The DNA sequence of this ActRIIB 2 clone A49-8/pSPORT with the missing -50 bp of coding region (assembled within the pJT6 expression vector as described below in Example 3) is shown in SEQ ID NO:3, and the deduced protein sequence of ActRIIB 2 in SEQ ID NO:4. The sequence is identical to the murine ActRIIB 2 sequence listed in GENBANK as accession number M84120 and described in Cell 68: 97-108 (1992), beginning at the ATG (base 44) of the published ActRIIB sequence through -900 bases, as well as the 3' end sequence (1460-1708 bases). For ActRIIB 2 , we have data confirming the sequence at ATG (base 44) through 900 bases, as well as the 3' end sequence (1460-1708). The sequencing data verifies this is the ActRIIB 2 variant as it contains the first insert (bp 413-436). The ActRIIB 4 variant does not contain either of the inserts, as indicated by the DNA sequence of the A46-3/pSPORT clone shown in SEQID NO: 7 and the protein sequence shown in SEQ ID NO: 8. For ActRIIB 4 , the clone isolated was full length and in addition contained - 300 bases of unknown sequence 5' to the ATG at bp 44. Example Construction of expression vectors for m-BRK-3. BRK-1. BRK-2. ActRIIB2, and ActRIIB4 The pJT4 expression vector has been previously described in U. S. Patent application serial number 08/462,467 by Rosenbaum, incorporated herein by reference. This expression vector has been optimized for transient expression in COS cells, and includes the cytomegalovirus early promoter and enhancer, which gives very efficient transcription of message; an "R" element from the long terminal repeat of the human T-cell leukemia virus-1, which has been shown to increase expression levels further; an intron splice site from SV40, which is believed to enhance message stability; a multiple wo 9W/'2UiZU PCT/US98/09519 33 cloning site; a polyadenylation signal derived from SV40, which directs the addition of a poly A tail to the message, as is required for most eukaryotic mRNA; and the SV40 origin of replication, which permits the replication of the plasmid to extremely high copy number in cells which contain the SV40 large T antigen, such as COS cells. In addition, for manipulation and amplification of the vector in bacteria, the vector contains an E. coli origin of replication and an ampicillin resistance gene. The expression vectors described herein are derivatives of the pJT4 expression vector, and are described below. For mammalian expression, m-ActRIIB 4 is subcloned into the mammalian expression vector pJT6. This vector is a derivative of pJT3, described in in U. S. Patent application serial number 08/462,467 by Rosenbaum, incorporated herein by reference, (see Example 4) in which the Not I site at the 5' end of the multiple cloning site has been deleted, and a spacer inserted between the Pst I and BamHI restriction sites in the multiple cloning site. To accomplish the subcloning, m-ActRIIB 4 cDNA is excised from A46-3/pSPORT using Not I and Sal I, then subcloned into pJT6 at the Not I and Sal I sites to generate pJT6-A46L. In order to assemble a full length clone of mouse ActRIIB 2 variant in the pJT6 expression vector, a Sal I site is first placed at the 5' end of clone A46-3/pSPORT as follows. A primer is synthesized which contains a Sal I site followed by nucleotides 1 15 of the coding sequence of A46-3/pSPORT; the sequence of the primer is 5' ATC GTC GAC CAT GAC GGC GCC CTG G 3' (SEQ ID NO:21). This is used together with the reverse primer, 5' GGG CGG AGG CCC CGG GTC 3' (SEQ ID NO:22), in order to amplify a DNA fragment using plasmid DNA from clone A46-3/pSPORT as the template. PCR is performed using the GENE-AMP PCR Kit with AMPLITAQ DNA Polymerase Polymerase (Perkin Elmer, Applied Biosystems, Foster City, CA). An initial melting period at 94oC for 5 min was followed by 30 cycles of the following program: melting at 94oC for 1 min, annealing at 55oC for 1 min, and extension at 72oC for 1 min. After the last cycle, the reaction was held at 72oC for 5 min to wo 9s8/52J PCT/US98/09519 34 complete extension. The fragment amplified from A46-3/pSPORT is inserted into pJT6 vector as follows. The amplified fragment from A46-3/pSPORT is digested with Sal I and Apa I. The insert from A49/pSPORT is digested with Apa I and Not I. The vector pJT6 is digested with Sal I and Not I. The three fragments are combined in a three-way ligation using T4 DNA ligase (3 hr, 25 0 C) and used to transform electrocompetent E. coli, strain DH5-a, using a BIO-RAD Gene PULSER (BIO-RAD, Hercules, CA) according to the manufacturer's instructions. A positive colony is selected and is designated pJT6-A49. Sequencing of the 5' portion of the insert that was amplified by PCR shows a sequence identical to that of clone A46-3/pSPORT, indicating that no mutations are introduced during the amplification. The construction of the expression plasmids for the mBRK-3, mBRK-1, and chicken BRK-2 clones has been previously described in detail in U. S. Patent application serial number 08/462,467 by Rosenbaum, incorporated herein by reference. To determine the effects of co-expression of mActRIIB 2 or mActRIIB 4 with type I BMP receptors, it is necessary to co-express the cDNA for mActRIIB 2 or mActRIIB 4 with the cDNA for BRK-I or the cDNA for BRK-2. The DNA sequence for mouse BRK-1 is shown in SEQ ID NO: 13, and the deduced amino acid sequence for mouse BRK-1 is shown in SEQ ID NO: 14. The DNA sequence for chicken BRK-2 is shown in SEQ ID NO: 15, and the deduced protein sequence shown for chicken BRK-2 is shown in SEQ ID NO: 16. To compare the binding and signaling properties of mActRIIB 2 with m-BRK-3 previously described in detail in U. S. Patent application serial number 08/462,467 by Rosenbaum, incorporated herein by reference, data obtained after co-expression of the type I receptors with BRK-3 are included in the following examples where indicated, for comparison purposes. The DNA sequence for mouse BRK-3 is shown in SEQ ID NO:11, and the deduced amino acid sequence for mouse BRK-3 is shown in SEQ ID NO:12. Example 4 Mammalian expression of mActRIIB2_ mActRIIB, m-BRK-3, BRK-1, and BRK-2 WO 98/5203i PCT/US98/09519 35 Transient expression of the receptors in mammalian cells using the expression plasmids described above is carried out in COS-1 cells (ATCC CRL 1650) or RIB/L-17 cells (J.L. Wrana, L. Attisano, J. Circamo, A. Zentella, J. Doody, M. Laiho, X.-F. Wang, and J. Massagu6, Cell 71:1003-1014 (1992)) for the binding and immunoprecipitation studies (Examples 6-8 below) or RIB/L-17 cells (J.L. Wrana, L. Attisano, J. Circamo, A. Zentella, J. Doody, M. Laiho, X.-F. Wang, and J. Massagu6, Cell 71:1003-1014 (1992)) for the signaling assays (Example 9), using DEAE Dextran (Pharmacia Biotech, Piscataway, NJ). For transient expression of BMP receptors in COS-1 cells, the cells are grown to approximately 70%-90% confluencey in DME high glucose media (Life Technologies, Gaithersburg, MD) supplemented with 10% fetal bovine serum (HyClone, Logan, Utah), nonessential amino acids, and glutamine in T-175 flasks (Corning, San Diego, CA). The cells are washed twice with 37 0 C serum-free DME media, after which 10 ml of DNA mixture is added to each T-175 flask. The DNA mixture contains DME, 10% Nu-Serum (Collaborative Biomedical Products, Bedford, MA), 400 pg/ml DEAE-Dextran (Pharmacia, Piscataway, NJ), 0.1 mM chloroquine (Sigma, St. Louis, MO), and the cDNAs of interest: for mActRIIB 2 , 40 tg of pJT6 mActRIIB 2 , for mActRIIB 4 , 40 pg of pJT6-mActRIIB 4 , for mBRK-3S, 40 pg of pJT6 mBRK-3S, for BRK-1, 20 pg pJT4-J159F; for BRK-2, 20 jg pJT3-BRK2. When the experimental design requires transfection of a single receptor only, the empty expression vector pJT6 or pJT4 (described in detail in U.S. Patent Application Serial Number 08/462,467 by Rosenbaum, incorporated herein by reference) is substituted for the corresponding receptor cDNA. The cells are then incubated at 370C with the DNA mixture for 3 hr. The solution is aspirated and the cells are incubated with 10 ml of a solution containing 10% dimethylsulfoxide (DMSO) in Dulbecco's phosphate buffered saline without calcium or magnesium (PBS; Life Technologies, Gaithersburg, MD). After 2 min, the DMSO solution is aspirated, the cells are washed with the growth media described above, and fresh media is returned to the plates. The transfected cells wo 98/5203i PCT/US98/09519 36 are split into 12 well plates 24 hr post transfection for whole cell binding (Example 6) or 100 mmn plates for affinity labeling and immunoprecipitation (Example 7). 36 to 72 hours after transfection the cells are suitable for binding analysis. For transient expression of BMP receptors in RIB/L-17 cells for the binding and affinity labeling/immunnoprecipitation studies, the conditions are identical to that described above for the COS-1 cells except that MEM media (Life Technologies, Gaithersburg, MD) is used in place of DME-high glucose media, and R1B/L-17 cells were transfected 24 hours after seeding in a T-175 flask (Corning, San Diego, CA) at 5-10 x 106 cells per flask. For transient expression of BMP receptors in RIB/L-17 cells for the 3TP-Lux assay, the conditions are identical to that described immediately above, except that 30 pg of the 3TP-Lux reporter plasmid (J.L. Wrana, L. Attisano, J. Circamo, A. Zentella, J. Doody, M. Laiho, X.-F. Wang, and J. Massagu6, Cell 71:1003-1014 (1992)) and 15 p.g of the pCMVP3 P-galactosidase expression plasmid (Clontech, Palo Alto, CA) are added in addition to the receptor plasmids. When the experimental design requires transfection of a single receptor only, the empty expression vector pJT6 or pJT4 (described in detail in U.S. Patent Application 08/462,467 by Rosenbaum and incorporated herein by reference) is substituted for the corresponding receptor cDNA. Example 5 Generation of the Radiolabeled BMP-4 Ligand Recombinant human BMP-2 and BMP-4 dimers are produced and purified from CHO cells as previously described (B.B. Koenig et al., Molecular and Cellular Biology, 14: 5961-5974 (1994)). [ 12 5 I]-BMP-4 is prepared using IODOBEADS (Pierce, Rockford, IL; immobilized chloramine-T on nonporous polystyrene beads). Lyophilized BMP-4 (2 pg) is taken up in 50 Al of 10 mM acetic acid and added to 450 Al of phosphate-buffered saline (PBS) (Sigma, St. Louis, MO) on ice. To the tube is added 500 ACurie of 125I (Amersham, Arlington Heights, IL) (2200Ci/mmol) in 5 Al, and one IODOBEAD. The reaction is incubated on ice for 10 min with occasional WO 98/niuss PCT/US98/09519 37 shaking. The reaction is then terminated by removal of the reaction from the IODOBEAD. To remove unreacted 125I, the mixture is applied to a PD-10 gel filtration column (Pharmacia, Piscataway, NJ) previously equilibrated in 10 mM acetic acid, 0.1 M NaC1, 0.25% gelatin. The resulting labeled protein is > 95 % precipitable by trichloroacetic acid, indicating that all 125I is protein bound, and has a typical specific activity of 4000 to 9000 Ci/mmol. Alternatively, BMP-4 is labeled with 125I by the chloramine-T method (C.A. Frolik, L.M. Wakefield, D.M. Smith, and M.B. Sporn, J. Biol. Chem., 259: 10995 11000 (1984)). BMP-4 (2 pg) is taken up in 5 tl of 30% acetonitrile, 0.1% trifluoracetic acid (TFA) plus an additional 5 ptl of 1.5 M sodium phosphate, pH 7.4. Carrier free 125I (1 mCi, 9 tl) is added, together with 2 .l of a chloramine T solution (100 Ig/ml). An additional 2 ptl of the chloramine T solution is added at 2.0 min and at 3.5 min. After 4.5 minutes, the reaction is stopped by the addition of 10 il of 50 mM N-acetyl tyrosine, 100 /l of 60 mM potassium iodide, and 100 1 l of 11M urea in 1 M acetic acid. After a 3.5 minute incubation, unreacted iodine is removed on a PD-10 gel filtration column (Pharmacia, Piscataway, NJ) run in 10 mM acetic acid, 0.1 M NaCl, 0.25% gelatin. The resulting labeled protein is >95% precipitable by trichloroacetic acid, indicating that all 125I is protein bound, and has a typical specific activity of 3000-8000 Ci/mmol. Example 6 Characterization of BMP-4 Binding Affinity to mActRIIB2 in the presence of a BMP type I receptor Binding of BMP-4 to mActRIIB 2 in the presence of the BMP type I receptors can be demonstrated by whole cell binding of radiolabeled BMP-4, and by covalent crosslinking (affinity labeling) and immunoprecipitation of radiolabeled BMP-4 to the receptor. These two methods are described in detail in this Example and in Example 7 below. Whole Cell Binding Competition Analysis: WU 98/52is5 PCT/US98/09519 38 COS-1 cells are transfected with pJT6-mActRIIB 2 for mActRIIB 2 expression, or pJT6-mActRIIB 4 for mActRIIB 4 expression; in the presence of pJT4-J159F for BRK-1 expression, or pJT3-BRK2 for BRK-2 expression, as described in Example 4. After transfection, cells are seeded into 12 well plates and the binding experiments are carried out at 24 to 36 hr. after plating. At that time, cells are washed once with binding buffer (50 mM HEPES, pH 7.4, 128 mM NaC1, 5 mM KC1, 5 mM MgSO4, 1.2 mM CaCl2, 2 mg/ml BSA), then equilibrated in the same buffer at 4C for 30 - 60 min with gentle shaking. The buffer is then aspirated, and to each well is added 500 IL of binding buffer (40 C), containing [ 12 5 I]-BMP-4 tracer (100 - 400 pM), as well as varying concentrations of unlabeled BMP-2, BMP-4, or other unlabeled ligand, depending on the assay. For determination of nonspecific binding, BMP-4 is added to the binding buffer at a final concentration of 10 to 50 nM. To prevent degradation of ligand during the incubation, a protease inhibitor cocktail is also added, to give a final concentration of 10 Ig/ml leupeptin, 10 /g/ml antipain, 50 Ag/ml aprotinin, 100 tg/ml benzamidine, 100 pg/ml soybean trypsin inhibitor, 10 Ig/ml bestatin, 10 zg/ml pepstatin, and 300 pM phenylmethylsulfonyl fluoride (PMSF). The cells are incubated for 4 hr at 4oC with gentle shaking. At the end of the incubation period, the buffer is aspirated, and the cells are rinsed 4 times with 1 ml washing buffer (50 mM HEPES, pH 7.4, 128 mM NaC1, 5 mM KC1, 5 mM MgSO4, 1.2 mM CaCl2, 0.5 mg/ml BSA). After the final wash is aspirated, 200 pl of RIPS buffer (20 mM Tris Base, 100mM NaC1, 1 mM EDTA, 0.5% NP-40, 0.5% Deoxycholic Acid, 0.1% SDS, 10 mM Nal, 1% BSA, pH 8.0) is added to each well and incubated at room temperature for 15 - 30 min. The solubilized cells are then transferred to fresh tubes and counted in a Packard Model 5005 COBRA Gamma Counter (Packard Instruments, Meriden, CT). The results of a [125I]BMP-4 competition experiment that compares the binding affinity of unlabeled BMP-4 in cells expressing BRK-1 alone vs. cells expressing mBRK-1 in the presence of mActRIIB2 indicates that the affinity of BMP-4 to the BRK 1 + ActRIIB 2 complex is higher (IC 5 0 < 5 x 10 -1 0 M) than it is to the BRK-1 type I WO 98/5I2U.5 PCT/US98/09519 39 receptor alone (IC 5 0 > 10-9 M). This is evidenced as a shift in the competition curve to the left in cells co-expressing BRK-1 + ActRIIB 2 , compared to the position of the competition curve in cells expressing BRK-1 alone. A similar leftward shift of the competition curve was obtained in cells co-expressing BRK-1 + ActRIIB 2 vs. cells expressing only BRK-1 in three additional experiments. The data average to an IC 5 0 = 2.59 x 10-10 M (Log IC 5 0 = -9.586 ± 0.062; N = 4) in cells co-expressing BRK-1 + ActRIIB 2 and 2.33 x 10 -9 M (Log IC 50 so = -8.633 + 0.044; N = 4) in cells expresing BRK-1 only. As an increase in binding affinity has been observed in cells co expressing the BRK-2 type I receptor with the BRK-3 type II receptor, but not in cells co-expressing BRK-1 + BRK-3 receptors (T. Nohno, T. Ishikawa, T. Saito, K. Hosokawa, S. Noji, D.H. Wolsing, and J. S. Rosenbaum, J. Biological Chemistry 270:22522-22526 (1995)), these data indicate that the ActRIIB 2 type II receptor represents a type II receptor that is capable of forming a high affinity binding complex for BMP-4 in the presence of the BRK-1 receptor; and as such BRK-1 + ActRIIB 2 represents a novel high affinity BMP receptor complex. Example 7 Demonstration of Complex Formation of mActRIIB but not mActRIIB4 with Type I BMP Receptors Receptors of the TGF-B receptor family have been shown to form complexes involving a type I and a type II receptor (L. Attisano, J.L. Wrana, F. Lopez Casillas, and J. Massagu6, J. Biochim Biophys. Acta, 1222: 71-80 (1994)). In order to demonstrate that the eight amino acids in the extracellular juxtamembrane region of ActRIIB 2 but not in ActRIIB 4 (L. Attisano, J.L. Wrana, S. Cheifetz, and J. Massagu6, Cell 68: 97-108 (1992)) are required for [125 I]BMP-4 binding and complex formation with the BMP type I receptors BRK-1 or BRK-2, COS-1 or RIB/L-17 cells are co-transfected with the cDNA for either mActRIIB 2 or mActRIIB 4 as the type II receptor in combination with either BRK-1 or BRK-2 as the type I receptor, as described in Example 4, and plated at a density of 3 x 106 cells/dish into WO 98/52UJ8 PCT/US98/09519 40 100 mm dishes as described previously (B.B. Koenig et al., Molecular and Cellular Biology, 14: 5961-5974 (1994)). The receptors are crosslinked to [ 12 5 I]-BMP-4, then subjected to immunoprecipitation with antibodies specific for the type I receptors BRK-1 and BRK-2 described below using previously described methods (T. Nohno, T. Ishikawa, T. Saito, K. Hosokawa, S. Noji, D.H. Wolsing, and J. S. Rosenbaum, J. Biological Chemistry 270:22522-22526 (1995); B.B. Koenig et al., Molecular and Cellular Biology, 14: 5961-5974 (1994)). If antibodies specific for a type I receptor precipitate not only the type I receptor crosslinked to [ 12 5 I]-BMP-4, but also mActRIIB 2 crosslinked to [ 12 5 I]-BMP-4, this indicates that the two receptors must be forming a complex, as expected for type I and type II receptors having the same ligand-binding specificity. The BRK-1 rabbit polyclonal antibody #1353 is raised against the E. coli produced extracellular domain and produced as described previously (B.B. Koenig et al., Molecular and Cellular Biology, 14: 5961-5974 (1994)). The BRK-2 rabbit polyclonal antibody JM#2 was raised against the intracellular juxtamembrane peptide ARPR Y SIGLEQDETYIPPC (AA: 155-172) conjugated by standard methods to keyhole limpet, and used to immunize three New Zealand White rabbits (Berkeley Antibody Company, Richmond, CA 94806-1965). The resulting antisera are evaluated for their ability to recognize the original peptide coated on plastic, using an antibody capture ELISA via the COOH cysteine. For both of these antibodies, antisera was IgG purified over a Pierce Immunopure Plus Immobilized Protein A column (Pierce Chemical Company, Rockford, IL) using the Immunopure (A) IgG Purification Kit (product # 44667) as described by the manufacturer. Complex formation between BRK-1 and ActRIIB 2 is demonstrated in two different experiments. The first experiment is performed in RIB/L-17 cells which do not express receptors to the levels observed in the COS-1 cells (D. Vivien, L. Attisano, J.L. Wrana, and J. Massagu6, J. Biological Chemistry, 270:7134 7141(1995)). In the RIB/L-17 cells, complex formation is observed between either wu 9ivauiZ PCT/US98/09519 41 the BRK-1 or the BRK-2 type I receptor and the BRK-3 type II receptor, as previously described in COS-1 cells (T. Nohno, T. Ishikawa, T. Saito, K. Hosokawa, S. Noji, D.H. Wolsing, and J. S. Rosenbaum, J. Biological Chemistry 270:22522-22526 (1995)). As is observed previously, in BRK-1 immunoprecipitates, the intensity of affinity labeling to the BRK-1 band is unchanged in the BRK-1 + BRK-3 co-expressing cells vs. that observed in the cells only expressing BRK-1; whereas it is considerably darker to the BRK-2 band in the BRK 2 immunoprecipitates from BRK-2 + BRK-3 co-expressing cells, vs. that observed in the cells only expressing BRK-2. This change in labeling intensity has been interpreted as being reflective of either an increased affinity or crosslinking efficiency when BRK-2, but not BRK-1 is present in a complex with the BRK-3 type II receptor (T. Nohno, T. Ishikawa, T. Saito, K. Hosokawa, S. Noji, D.H. Wolsing, and J. S. Rosenbaum, J. Biological Chemistry 270:22522-22526 (1995)). In RIB/L-17 cells, an increased intensity of labeling of the BRK-1, but not the BRK 2 type I receptor band is observed in type I receptor immunoprecipitates when these receptors are coexpressed with ActRIIB 2 . In addition, affinity labeling of a band corresponding to the molecular weight of ActRIIB 2 (L. Attisano, J.L. Wrana, S. Cheifetz, and J. Massagu6, Cell 68: 97-108 (1992)) is observed in BRK-1 immunoprecipitates in cells co-expressing BRK-1 + ActRIIB 2 , but not in BRK-1 immunoprecipitates in cells expressing only the BRK-1 receptor. This indicates that BRK-1 forms a complex with ActRIIB 2 in cells co-expressing both of these receptors. Complex formation is not observed between BRK-2 and ActRIIB 2 , as affinity labeling of the band corresponding to the molecular weight of ActRIIB 2 is not observed in the BRK-2 immunoprecipitates in cells co-expressing BRK-2 and ActRIIB 2 . Furthermore, affinity labeling of a band corresponding to the molecular weight of ActRIIB 4 (L. Attisano, J.L. Wrana, S. Cheifetz, and J. Massagu6, Cell 68: 97-108 (1992)) is not observed in type I receptor immunoprecipitates in cells cowual5/ZLUJ5 PCT/US98/09519 42 expressing either type I receptor with ActRIIB 4 , indicating that ActRIIB 4 does not form a complex with either BRK-1 or BRK-2 in the presence of [125 I]BMP-4. A similar experiment is performed in COS-1 cells, and complex formation between BRK-1 and ActRIIB 2 , but not BRK-1 + ActRIIB 4 is demonstrated using the same criterion as that applied in the experiment in the RIB/L-17 cells. In addition, in the COS-1 cells, which express receptors to a higher level than that observed in the RIB/L-17 cells (D. Vivien, L. Attisano, J.L. Wrana, and J. Massagu6, J. Biological Chemistry, 270:7134-7141(1995)), complex formation is also demonstrated with BRK-2 + ActRIIB 2 . These data confirm that the eight amino acids present in the extracellular juxtamembrane region of ActRIIB and ActRIIB 2 (L. Attisano, J.L. Wrana, S. Cheifetz, and J. Massagu6, Cell 68: 97-108 (1992)) are critical for binding of BMP-4 to the ActRIIB type II receptor. Furthermore, the data indicate that either BRK-1 or BRK-2 are competetent to form a complex with ActRIIB 2 in the presence of [125 I]BMP-4 ligand, but that complex formation between BRK-2 and ActRIIB 2 requires higher levels of receptor expression than that nececessary for complex formation between BRK-1 and ActRIIB 2 . An additional experiment indicates that the BRK-2 + ActRIIB 2 complex is also capable of binding BMP-2. In this experiment COS-1 cells are co-transfected with BRK-2 and ActRIIB 2 and are affinity labeled with [1 25I]BMP-2 as previously described (B.B. Koenig et al., Molecular and Cellular Biology, 14: 5961-5974 (1994)). As described above for [125 I]BMP-4, affinity labeling of a band corresponding to the molecular weight of ActRIIB 2 is observed in BRK-2 immunoprecipitates in cells co-expressing BRK-2 + ActRIIB 2 , indicating that BMP 2 ligand is capable of binding to the BRK-2 + ActRIIB 2 complex when these receptors are overexpressed in COS-1 cells. Example 8 Use of m-ActRIIB + BRK-1 or m-tRIRIIB, + BRK-2 in a ligand binding assay for the identification of BMP receptor agonists and antagonists WO 98/52038 PCTIUS98/09519 43 Identification of ligands that interact with mActRIIB 2 complexed to a type I BMP receptor can be achieved through the use of assays that are designed to measure the interaction of the ligands with this BMP receptor complex. A receptor binding assay that uses the m-ActRIIB 2 + BRK-1 or mActRIIB 2 + BRK-2 complex and is adapted to handle large numbers of samples is carried out as follows. COS-1 cells are transfected with the cDNAs for m-ActRIIB 2 , using the construct pJT6-mActRIIB 2 , and either BRK-1, using the construct pJT4-J159F for BRK-1 expression, or BRK-2, using the construct pJT3-BRK-2 for BRK-2 expression, as described in Example 4 above, except that the cells are grown in a 12 well culture dish or a 96-well microtitre plate. The DNA mixture used to transfect the cells contains the receptors in the concentrations described above in Example 4. At 36-72 hours after transfection, the cells are washed once with binding buffer (50 mM HEPES, pH 7.4, 128 mM NaC1, 5 mM KCL, 5 mM MgSO4, 1.2 mM CaCl2, 2 mg/ml BSA), then equilibrated in the same buffer at 4 0 C for 60 min with gentle shaking. After equilibration, the buffer is aspirated, and to each well is added 4oC binding buffer containing [1 2 5I]BMP-4 tracer (100-400 pM) in the presence or absence of varying concentrations of test compounds (i.e., putative ligands), for a period of 4 hours at 4oC with gentle shaking. For determination of nonspecific binding and complete displacement from the BMP receptor complex, BMP-2 is added at a final concentration of 10 nM. To prevent degradation of ligand, a protease inhibitor cocktail is also added, to give a final concentration of 10 pg/ml leupeptin, 10 tg/ml antipain, 50 tg/ml aprotinin, 100 pg/ml benzamidine, 100 jyg/ml soybean trypsin inhibitor, 10 yg/ml bestatin, 10 gtg/ml pepstatin, and 300 pM phenylmethylsulfonyl fluoride (PMSF). At the end of the incubation period, the buffer is aspirated, and the cells are rinsed 4 times with washing buffer (50 mM HEPES, pH 7.4, 128 mM NaC1, 5 mM KCI, 5 mM MgSO4, 1.2 mM CaCl2, 0.5 mg/ml BSA). After the final wash is aspirated, RIPS buffer (20 mM Tris Base, 100mM NaC1, 1 mM EDTA, 0.5% NP-40, 0.5% Deoxycholic Acid, 0.1% SDS, 10 mM Nal, 1% BSA, pH 8.0.) is added to each well WO 9/2U35 PCT/US98/09519 44 and incubated at room temperature for 15-30 min. The solubilized cells are then transferred to fresh tubes and counted in a Packard Model 5005 COBRA Gamma Counter (Packard Instruments, Meriden, CT). Test compounds which interact with the mActRIIB 2 + BRK-1 or mActRIIB 2 + BRK-2 receptor complex are observed to compete for binding to the receptor complex with the [125I]BMP-4 tracer, such that less [125I]BMP-4 tracer is bound in the presence of the test compound in comparison to the binding observed when the tracer is incubated in the absence of the novel compound. A decrease in binding of the [125I]BMP-4 tracer by > 30% at the highest concentration of the test compound that is studied demonstrates that the test compound binds to the mActRIIB 2 + BRK-1 or mActRIIB 2 + BRK-2 receptor complex. Example Demonstration of BMP-mediated signaling through mActRIIB_ but not mActRIIB in a Complex With Type I BMP Receptors Since several laboratories have previously demonstrated use of the R1B/L 17 mink lung epithelial cells (L. Attisano, J. Carcamo, F. Ventura, F.M.B. Weis, J. Massagu6, and J.L. Wrana, Cell 75:671-680 (1993); J. Circamo, F.M.B. Weis, F. Ventura, R. Wieser, J.L. Wrana, L. Attisano, and J. Massague, Molecular and Cellular Biology 14:3810-3821 (1994)) in concert with the p3TP-Lux promoter construct (J.L. Wrana, L. Attisano, J. Circamo, A. Zentella, J. Doody, M. Laiho, X.-F. Wang, and J. Massagu6, Cell 71:1003-1014 (1992)) to measure signaling of TGF-P (L. Attisano, J. Circamo, F. Ventura, F.M.B. Weis, J. Massagu6, and J.L. Wrana, Cell 75:671-680 (1993); J.L. Wrana, L. Attisano, J. Circamo, A. Zentella, J. Doody, M. Laiho, X.-F. Wang, and J. Massagu6, Cell 71:1003-1014 (1992)), activin (L. Attisano, J.L. Wrana, E. Montalvo, and J. Massagu6, Molecular and Cellular Biology 16:1066-1073 (1996); J. Circamo, F.M.B. Weis, F. Ventura, R. Wieser, J.L. Wrana, L. Attisano, and J. Massagu6, Molecular and Cellular Biology 14:3810-3821 (1994); S.A. Willis, C.M.

WO 98/52U38 PCT/US98/09519 45 Zimmerman, L. Li, and L.S. Mathews, Molecular Endocrinology 10:367-379 (1996)) and BMP (F. Liu, F. Ventura, J. Doody, and J. Massagu6, Molecular and Cellular Biology, 15: 3479-3486 (1995); B.L. Rosenzweig, T. Imamura, T. Okadome, G.N. Cox, H. Yamashita, P. Ten Dijke, C.-H. Heldin, and K. Miyazono, Proceedings of the National Academy of Sciences, U.S.A., 92: 7632 7636 (1995); H. Yamashita, P. ten Dijke, D. Huylebroeck, T.K. Sampath, M. Andries, J.C. Smith, C.-H. Heldin, and K. Miyazono, J. Cell Biology 130:217 226 (1995)) receptor complexes, we also used this reporter system to demonstrate the use of mActRIIB 2 + BRK-1 in a signaling assay that can then be used for the identification of BMP receptor agonists and antagonists. R-1B/L17 cells are transfected with various BMP receptor pairs, the 3TP Lux reporter plasmid (J.L. Wrana, L. Attisano, J. Circamo, A. Zentella, J. Doody, M. Laiho, X.-F. Wang, and J. Massagu6, Cell 71:1003-1014 (1992)), and a P3-galactosidase reporter construct driven by the CMV promoter (Clontech, Palo Alto, CA) as described in Example 4, and, after 24 hours, are plated at 2x10 5 cells per well in six well standard tissue culture plates (Corning, San Diego, CA). After allowing cells to recover for 3 to 4 hours in 10%FBS-MEM, the growth media is replaced with 0.1%FBS-MEM for 2 to 4 hours. BMPs are then applied in increasing concentrations in 0.1%FBS-MEM for 18 hours prior to cell harvesting. Cells are harvested and assayed for luciferase activity using the Dual Light System (Tropix, Bedford, MA) as described by the manufacturer. To eliminate variation from well to well and assay to assay, reported luciferase activity values are normalized to the P3-galactosidase values reported for the same aliquot (determined using the Dual Light System (Tropix, Bedford, MA) as described by the manufacturer), and all data are expressed as arbitrary units. Demonstration that signaling is achieved with the BRK-1 + ActRIIB 2 , but not the BRK-1 + ActRIIB 4 complex is demonstrated using the 3TP-Lux reporter system in two separate experiments. In the first experiment, the type I and type II WO 98/52U0i8 PCT/US98/09519 46 receptors are expressed either individually or in combination in the RIB/L-17 cells in the presence of the 3TP-Lux or P-galactosidase reporter genes. This experiment demonstrates that neither the type I nor the type II receptors are capable of signaling on their own, as has previously been observed with BRK-1, BRK-2, and BRK-3 in this system (F. Liu, F. Ventura, J. Doody, and J. Massagu6, Molecular and Cellular Biology, 15: 3479-3486 (1995); B.L. Rosenzweig, T. Imamura, T. Okadome, G.N. Cox, H. Yamashita, P. Ten Dijke, C.-H. Heldin, and K. Miyazono, Proceedings of the National Academy of Sciences, U.S.A., 92: 7632-7636 (1995); H. Yamashita, P. ten Dijke, D. Huylebroeck, T.K. Sampath, M. Andries, J.C. Smith, C.-H. Heldin, and K. Miyazono, J. Cell Biology 130:217-226 (1995)). However, the previous studies did not address BMP-mediated signaling through these type I receptors in the presence of the ActRIIB type II receptor, and the data presented here demonstrate that the BRK-1 + ActRIIB 2 complex, but not the BRK-1 + ActRIIB 4 complex, produces a BMP-4-stimulated increase in 3TP-Lux reporter activity. These data indicate for the first time that BRK-1 + ActRIIB 2 represent a signaling receptor complex for BMP-4 in this assay, and that the eight amino acids in the extracellular juxtamembrane region of ActRIIB 1 or ActRIIB 2 that are absent in the ActRIIB 3 and ActRIIB 4 isoforms (L. Attisano, J.L. Wrana, S. Cheifetz, and J. Massagu6, Cell 68: 97-108 (1992)) are critical for this activity. It is also interesting that BRK-2 + ActRIIB 2 produce a much lower degree of stimulation in this assay than is observed with BRK-1 + ActRIIB 2 at this single concentration of BMP-4. In the second experiment, complete dose-response curves are compared for BMP-4 in RIB cells co-expressing either BRK-1 + ActRIIB 2 or BRK-1 + ActRIIB 4 in addition to the 3TP-Lux and P3-galactosidase reporter constructs. This experiment demonstrates an EC 50 for BMP-4 of 6.4 x 10

-

11 M at the BRK-1 + ActRIIB 2 complex but only a negligable response at the BRK-1 + ActRIIB 4 complex.

wo 9/SfAJUS PCT/US98/09519 47 Since BMP-2 and BMP-4 both bind to the BRK-1 receptor (B.B. Koenig et al., Molecular and Cellular Biology, 14: 5961-5974 (1994)), it is necessary to demonstrate that BMP-2 is capable signaling through the BRK-1 + ActRIIB 2 complex in the 3TP-Lux reporter assay. This is demonstrated in a third experiment, where it is demonstrated that BMP-4 exhibits an EC 50 so of 1.5 x 10 -1 0 M and BMP-2 exhibits an EC 50 so of 2.8 x 10

-

10 M. The experiment also demonstrates a similar maximal response (5-fold) for these two ligands. These data demonstrate that the BRK-1 + ActRIIB 2 complex is a signaling receptor complex for either BMP-2 or BMP-4, and that these BMP ligands exhibit similar potency and efficacy at this receptor complex. Example 1 Use of mActRIIB z and BRK-1 in a signaling assay for the identification of BMP receptor agonists and antagonists Test compounds which are agonists of the BRK-1 +ActRIIB 2 receptor complex will cause an increase in reporter activity in RIB cells co-expressing the BRK-1 and ActRIIB 2 receptors in combination with the 3TP-Lux and P3 galactosidase reporter genes, quantited via the arbitrary light units the level of luciferase activity produced by activation of the luciferase enzyme normalized to the arbitrary light units produced by activation of the P-galactosidase enzyme as described for BMP-2 or BMP-4 in Example 9 above. In this manner, RIB/L-17 cells expressing co-expressing the BRK-1 and ActRIIB 2 receptors in combination with the 3TP-Lux and P-galactosidase reporter genes are produced as described in Examples 4 and 9 above are exposed to various concentrations of unknown agents, and the cells are evaluated for their response, quantited via the arbitrary light units the level of luciferase activity produced by activation of the luciferase enzyme normalized to the arbitrary light units produced by activation of the P3 galactosidase enzyme as described for BMP-2 or BMP-4 in Example 9 above. Those compounds which produce an activity in RIB/L-17 cells expressing BRK-1 WO 98/52038 PCT/US98/09519 48 + ActRIIB 2 receptors in combination with the 3TP-Lux and P-galactosidase genes, but not in RIB/L-17 cells which express only the 3TP-Lux and P-galactosidase genes are said to act as agonists of the BRK-1 + ActRIIB 2 receptor complex. In order to test for antagonist activity, test compounds are added to RIB/L 17 cells expressing BRK-1 + ActRIIB 2 receptors in combination with the 3TP Lux and P-galactosidase genes in the presence of a fixed concentration of BMP-4 or another BMP receptor agonist. Test compounds which are antagonists of BRK 1 +ActRIIB 2 complex will cause a decrease in the reporter activity of the 3TP Lux construct, quantited via the arbitrary light units the level of luciferase activity produced by activation of the luciferase enzyme normalized to the arbitrary light units produced by activation of the p-galactosidase enzyme as described for BMP 2 or BMP-4 in Example 9 above, when activity is compared to that observed in cells exposed to BMP-4 or another BMP receptor agonist in the absence of the added test compound. U. S. Patent application serial number 08/462,467 by Rosenbaum, which is also incorporated herein by reference and is used to supplement any disclosure in U. S. Patent Application Serial number 08/334,179, filed November 4, 1994 by Rosenbaum and Nohno is hereby incorporated herein by reference. All other publications mentioned hereinabove are hereby incorporated in their entirety by reference. It is understood that the examples and embodiments described herein are for illustrative purposes only and that various modifications or changes in light thereof will be suggested to one skilled in the art and are to be included in the spirit and purview of this application and scope of the appended claims.

WO 98/52038 PCT/US98/09519 49 SEQUENCE LISTING (1) GENERAL INFORMATION: (i) APPLICANT: Rosenbaum, Jan S. (ii) TITLE OF INVENTION: THE USE OF A BONE MORPHOGENETIC PROTEIN (BMP) RECEPTOR COMPLEX FOR SCREENING CELLULAR DIFFERENTIATION ACTIVES AND CELLS CO-TRANSFECTED WITH AN ACTIVIN/BMP TYPE II RECEPTOR AND A BMP TYPE I RECEPTOR (iii) NUMBER OF SEQUENCES: 22 (iv) CORRESPONDENCE ADDRESS: (A) ADDRESSEE: The Procter & Gamble Company (B) STREET: 8700 Mason-Montgomery Road (C) CITY: Mason (D) STATE: OH (E) COUNTRY: USA (F) ZIP: 45040-9462 (v) COMPUTER READABLE FORM: (A) MEDIUM TYPE: Floppy disk (B) COMPUTER: IBM PC compatible (C) OPERATING SYSTEM: PC-DOS/MS-DOS (D) SOFTWARE: PatentIn Release #1.0, Version #1.30 (vi) CURRENT APPLICATION DATA: (A) APPLICATION NUMBER: (B) FILING DATE: (C) CLASSIFICATION: (viii) ATTORNEY/AGENT INFORMATION: (A) NAME: Hake, Richard A. (B) REGISTRATION NUMBER: 37,343 (C) REFERENCE/DOCKET NUMBER: 10959 (ix) TELECOMMUNICATION INFORMATION: (A) TELEPHONE: 513/622-0087 (B) TELEFAX: 513/622-0270 (2) INFORMATION FOR SEQ ID NO:l: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 1722 base pairs (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: DNA (genomic) (ix) FEATURE: (A) NAME/KEY:

CDS

WO 98/5203 PCT/US98/09519 50 (B) LOCATION: 44..1654 (xi) SEQUENCE DESCRIPTION: SEQ ID NO:1: CCCTGCCCGC GGGCTCCGGG TGTCGCGGGG CGCGCCGCGG AAC ATG ACG GCG CCC 55 Met Thr Ala Pro 1 TGG GCG GCC CTC GCC CTT CTC TGG GGA TCG CTG TGC GCC GGT TCC GGG 103 Trp Ala Ala Leu Ala Leu Leu Trp Gly Ser Leu Cys Ala Gly Ser Gly 5 10 15 20 CGA GGG GAG GCT GAG ACT CGG GAG TGC ATC TAC TAC AAC GCC AAC TGG 151 Arg Gly Glu Ala Glu Thr Arg Glu Cys Ile Tyr Tyr Asn Ala Asn Trp 25 30 35 GAG CTG GAG CGC ACC AAC CAG AGC GGC CTG GAG CGC TGC GAG GGG GAA 199 Glu Leu Glu Arg Thr Asn Gln Ser Gly Leu Glu Arg Cys Glu Gly Glu 40 45 50 CAG GAC AAG CGG CTG CAC TGC TAC GCC TCG TGG CGC AAC AGC TCG GGC 247 Gln Asp Lys Arg Leu His Cys Tyr Ala Ser Trp Arg Asn Ser Ser Gly 55 60 65 ACC ATC GAG CTG GTG AAG AAG GGC TGC TGG CTA GAT GAC TTC AAT TGC 295 Thr Ile Glu Leu Val Lys Lys Gly Cys Trp Leu Asp Asp Phe Asn Cys 70 75 80 TAC GAC AGG CAG GAG TGT GTG GCC ACC GAG GAG AAC CCC CAG GTG TAC 343 Tyr Asp Arg Gln Glu Cys Val Ala Thr Glu Glu Asn Pro Gln Val Tyr 85 90 95 100 TTC TGC TGC TGC GAA GGC AAC TTC TGC AAC GAG CGC TTC ACC CAC TTG 391 Phe Cys Cys Cys Glu Gly Asn Phe Cys Asn Glu Arg Phe Thr His Leu 105 110 115 CCG GAG CCT GGG GGC CCA GAA GTC ACG TAC GAG CCA CCC CCG ACA GCC 439 Pro Glu Pro Gly Gly Pro Glu Val Thr Tyr Glu Pro Pro Pro Thr Ala 120 125 130 CCC ACC CTG CTC ACG GTG CTG GCC TAC TCG CTG CTG CCC ATT GGA GGC 487 Pro Thr Leu Leu Thr Val Leu Ala Tyr Ser Leu Leu Pro Ile Gly Gly 135 140 145 CTC TCT CTC ATC GTC CTG CTG GCC TTC TGG ATG TAT CGT CAT CGG AAA 535 Leu Ser Leu Ile Val Leu Leu Ala Phe Trp Met Tyr Arg His Arg Lys 150 155 160 CCT CCC TAC GGC CAT GTG GAC ATC CAT GAG GTG AGA CAG TGC CAG CGT 583 Pro Pro Tyr Gly His Val Asp Ile His Glu Val Arg Gln Cys Gln Arg 165 170 175 180 TGG GCA GGG AGA AGG GAC GGC TGT GCG GAC TCC TTT AAG CCC TTG CCT 631 Trp Ala Gly Arg Arg Asp Gly Cys Ala Asp Ser Phe Lys Pro Leu Pro 185 190 195 WO 98/520U8 PCT/US98/09519 51 TTC CAG GAC CCG GGG CCT CCG CCC CCA TCC CCT CTG GTG GGC CTG AAG 679 Phe Gln Asp Pro Gly Pro Pro Pro Pro Ser Pro Leu Val Gly Leu Lys 200 205 210 CCA CTA CAG CTG CTG GAG ATC AAG GCT CGG GGC CGC TTT GGC TGC GTT 727 Pro Leu Gln Leu Leu Glu Ile Lys Ala Arg Gly Arg Phe Gly Cys Val 215 220 225 TGG AAG GCT CAG CTC ATG AAC GAC TTT GTG GCT GTG AAG ATC TTC CCA 775 Trp Lys Ala Gln Leu Met Asn Asp Phe Val Ala Val Lys Ile Phe Pro 230 235 240 CTT CAG GAC AAG CAG TCG TGG CAG AGT GAA CGG GAA ATC TTC AGC ACA 823 Leu Gln Asp Lys Gln Ser Trp Gln Ser Glu Arg Glu Ile Phe Ser Thr 245 250 255 260 CCC GGC ATG AAG CAC GAA AAC TTG TTG CAG TTC ATT GCT GCC GAG AAA 871 Pro Gly Met Lys His Glu Asn Leu Leu Gln Phe Ile Ala Ala Glu Lys 265 270 275 CGA GGC TCC AAC CTG GAG GTG GAG CTG TGG CTC ATC ACA GCC TTC CAC 919 Arg Gly Ser Asn Leu Glu Val Glu Leu Trp Leu Ile Thr Ala Phe His 280 285 290 GAC AAG GGC TCC CTC ACG GAT TAC CTC AAG GGG AAC ATC ATC ACG TGG 967 Asp Lys Gly Ser Leu Thr Asp Tyr Leu Lys Gly Asn Ile Ile Thr Trp 295 300 305 AAC GAA CTG TGC CAC GTG GCG GAG ACG ATG TCA CGA GGC CTC TCA TAC 1015 Asn Glu Leu Cys His Val Ala Glu Thr Met Ser Arg Gly Leu Ser Tyr 310 315 320 CTG CAT GAG GAT GTG CCG TGG TGT CGT GGT GAG GGC CAC AAG CCT TCT 1063 Leu His Glu Asp Val Pro Trp Cys Arg Gly Glu Gly His Lys Pro Ser 325 330 335 340 ATT GCC CAC AGG GAC TTC AAA AGC AAG AAT GTA CTG CTG AAG AGC GAC 111iii1 Ile Ala His Arg Asp Phe Lys Ser Lys Asn Val Leu Leu Lys Ser Asp 345 350 355 CTC ACC GCG GTG CTG GCT GAC TTC GGC CTG GCT GTT CGG TTT GAG CCA 1159 Leu Thr Ala Val Leu Ala Asp Phe Gly Leu Ala Val Arg Phe Glu Pro 360 365 370 GGG AAG CCT CCT GGG GAT ACC CAT GGA CAG GTT GGC ACC AGA CGG TAC 1207 Gly Lys Pro Pro Gly Asp Thr His Gly Gln Val Gly Thr Arg Arg Tyr 375 380 385 ATG GCC CCT GAG GTG CTG GAA GGA GCC ATC AAC TTC CAG AGA GAC GCC 1255 Met Ala Pro Glu Val Leu Glu Gly Ala Ile Asn Phe Gln Arg Asp Ala 390 395 400 TTC CTG CGT ATC GAC ATG TAC GCC ATG GGC CTG GTG CTG TGG GAG CTC 1303 Phe Leu Arg Ile Asp Met Tyr Ala Met Gly Leu Val Leu Trp Glu Leu 405 410 415 420 WO 9/52U3J PCT/US98/09519 52 GTC TCT CGG TGC AAG GCT GCA GAC GGG CCT GTC GAT GAG TAC ATG CTG 1351 Val Ser Arg Cys Lys Ala Ala Asp Gly Pro Val Asp Glu Tyr Met Leu 425 430 435 CCC TTC GAG GAG GAG ATT GGC CAG CAC CCT TCG CTG GAG GAG CTT CAG 1399 Pro Phe Glu Glu Glu Ile Gly Gln His Pro Ser Leu Glu Glu Leu Gln 440 445 450 GAG GTG GTT GTC CAC AAG AAG ATG AGG CCC ACG ATT AAG GAT CAC TGG 1447 Glu Val Val Val His Lys Lys Met Arg Pro Thr Ile Lys Asp His Trp 455 460 465 CTG AAA CAC CCG GGC CTG GCC CAG CTC TGC GTG ACC ATC GAG GAG TGC 1495 Leu Lys His Pro Gly Leu Ala Gln Leu Cys Val Thr Ile Glu Glu Cys 470 475 480 TGG GAC CAT GAT GCA GAG GCT CGC CTT TCT GCA GGC TGT GTA GAA GAG 1543 Trp Asp His Asp Ala Glu Ala Arg Leu Ser Ala Gly Cys Val Glu Glu 485 490 495 500 CGG GTA TCC CTG ATC AGG AGG TCG GTC AAC GGC ACT ACC TCG GAC TGT 1591 Arg Val Ser Leu Ile Arg Arg Ser Val Asn Gly Thr Thr Ser Asp Cys 505 510 515 CTC GTC TCT CTG GTG ACC TCC GTC ACC AAT GTG GAC CTG CTC CCT AAA 1639 Leu Val Ser Leu Val Thr Ser Val Thr Asn Val Asp Leu Leu Pro Lys 520 525 530 GAG TCC AGC ATC TAA GCCCGGGACA CGTAGCGTCT CTCCAGACTC AGTGGATCTG 1694 Glu Ser Ser Ile * 535 AAGAAAAAAA AAAGTAAACG TACTCCAA 1722 (2) INFORMATION FOR SEQ ID NO:2: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 537 amino acids (B) TYPE: amino acid (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (xi) SEQUENCE DESCRIPTION: SEQ ID NO:2: Met Thr Ala Pro Trp Ala Ala Leu Ala Leu Leu Trp Gly Ser Leu Cys 1 5 10 15 Ala Gly Ser Gly Arg Gly Glu Ala Glu Thr Arg Glu Cys Ile Tyr Tyr 20 25 30 Asn Ala Asn Trp Glu Leu Glu Arg Thr Asn Gln Ser Gly Leu Glu Arg 35 40 45 WO 98/52UJ PCT/US98/09519 53 Cys Glu Gly Glu Gln Asp Lys Arg Leu His Cys Tyr Ala Ser Trp Arg 50 55 60 Asn Ser Ser Gly Thr Ile Glu Leu Val Lys Lys Gly Cys Trp Leu Asp 65 70 75 80 Asp Phe Asn Cys Tyr Asp Arg Gln Glu Cys Val Ala Thr Glu Glu Asn 85 90 95 Pro Gln Val Tyr Phe Cys Cys Cys Glu Gly Asn Phe Cys Asn Glu Arg 100 105 110 Phe Thr His Leu Pro Glu Pro Gly Gly Pro Glu Val Thr Tyr Glu Pro 115 120 125 Pro Pro Thr Ala Pro Thr Leu Leu Thr Val Leu Ala Tyr Ser Leu Leu 130 135 140 Pro Ile Gly Gly Leu Ser Leu Ile Val Leu Leu Ala Phe Trp Met Tyr 145 150 155 160 Arg His Arg Lys Pro Pro Tyr Gly His Val Asp Ile His Glu Val Arg 165 170 175 Gln Cys Gln Arg Trp Ala Gly Arg Arg Asp Gly Cys Ala Asp Ser Phe 180 185 190 Lys Pro Leu Pro Phe Gln Asp Pro Gly Pro Pro Pro Pro Ser Pro Leu 195 200 205 Val Gly Leu Lys Pro Leu Gln Leu Leu Glu Ile Lys Ala Arg Gly Arg 210 215 220 Phe Gly Cys Val Trp Lys Ala Gln Leu Met Asn Asp Phe Val Ala Val 225 230 235 240 Lys Ile Phe Pro Leu Gln Asp Lys Gln Ser Trp Gln Ser Glu Arg Glu 245 250 255 Ile Phe Ser Thr Pro Gly Met Lys His Glu Asn Leu Leu Gln Phe Ile 260 265 270 Ala Ala Glu Lys Arg Gly Ser Asn Leu Glu Val Glu Leu Trp Leu Ile 275 280 285 Thr Ala Phe His Asp Lys Gly Ser Leu Thr Asp Tyr Leu Lys Gly Asn 290 295 300 Ile Ile Thr Trp Asn Glu Leu Cys His Val Ala Glu Thr Met Ser Arg 305 310 315 320 Gly Leu Ser Tyr Leu His Glu Asp Val Pro Trp Cys Arg Gly Glu Gly 325 330 335 His Lys Pro Ser Ile Ala His Arg Asp Phe Lys Ser Lys Asn Val Leu 340 345 350 WO 98/52U38 PCT/US98/09519 54 Leu Lys Ser Asp Leu Thr Ala Val Leu Ala Asp Phe Gly Leu Ala Val 355 360 365 Arg Phe Glu Pro Gly Lys Pro Pro Gly Asp Thr His Gly Gln Val Gly 370 375 380 Thr Arg Arg Tyr Met Ala Pro Glu Val Leu Glu Gly Ala Ile Asn Phe 385 390 395 400 Gln Arg Asp Ala Phe Leu Arg Ile Asp Met Tyr Ala Met Gly Leu Val 405 410 415 Leu Trp Glu Leu Val Ser Arg Cys Lys Ala Ala Asp Gly Pro Val Asp 420 425 430 Glu Tyr Met Leu Pro Phe Glu Glu Glu Ile Gly Gln His Pro Ser Leu 435 440 445 Glu Glu Leu Gln Glu Val Val Val His Lys Lys Met Arg Pro Thr Ile 450 455 460 Lys Asp His Trp Leu Lys His Pro Gly Leu Ala Gln Leu Cys Val Thr 465 470 475 480 Ile Glu Glu Cys Trp Asp His Asp Ala Glu Ala Arg Leu Ser Ala Gly 485 490 495 Cys Val Glu Glu Arg Val Ser Leu Ile Arg Arg Ser Val Asn Gly Thr 500 505 510 Thr Ser Asp Cys Leu Val Ser Leu Val Thr Ser Val Thr Asn Val Asp 515 520 525 Leu Leu Pro Lys Glu Ser Ser Ile * 530 535 WO 98/52038 PCT/US98/09519 55 (2) INFORMATION FOR SEQ ID NO:3: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 1651 base pairs (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: DNA (genomic) (ix) FEATURE: (A) NAME/KEY: CDS (B) LOCATION: 44..1582 (xi) SEQUENCE DESCRIPTION: SEQ ID NO:3: CCCTGCCCGC GGGCTCCGGG TGTCGCGGGG CGCGCCGCGG AAC ATG ACG GCG CCC 55 Met Thr Ala Pro 1 TGG GCG GCC CTC GCC CTT CTC TGG GGA TCG CTG TGC GCC GGT TCC GGG 103 Trp Ala Ala Leu Ala Leu Leu Trp Gly Ser Leu Cys Ala Gly Ser Gly 5 10 15 20 CGA GGG GAG GCT GAG ACT CGG GAG TGC ATC TAC TAC AAC GCC AAC TGG 151 Arg Gly Glu Ala Glu Thr Arg Glu Cys Ile Tyr Tyr Asn Ala Asn Trp 25 30 35 GAG CTG GAG CGC ACC AAC CAG AGC GGC CTG GAG CGC TGC GAG GGG GAA 199 Glu Leu Glu Arg Thr Asn Gln Ser Gly Leu Glu Arg Cys Glu Gly Glu 40 45 50 CAG GAC AAG CGG CTG CAC TGC TAC GCC TCG TGG CGC AAC AGC TCG GGC 247 Gln Asp Lys Arg Leu His Cys Tyr Ala Ser Trp Arg Asn Ser Ser Gly 55 60 65 ACC ATC GAG CTG GTG AAG AAG GGC TGC TGG CTA GAT GAC TTC AAT TGC 295 Thr Ile Glu Leu Val Lys Lys Gly Cys Trp Leu Asp Asp Phe Asn Cys 70 75 80 TAC GAC AGG CAG GAG TGT GTG GCC ACC GAG GAG AAC CCC CAG GTG TAC 343 Tyr Asp Arg Gln Glu Cys Val Ala Thr Glu Glu Asn Pro Gln Val Tyr 85 90 95 100 TTC TGC TGC TGC GAA GGC AAC TTC TGC AAC GAG CGC TTC ACC CAC TTG 391 Phe Cys Cys Cys Glu Gly Asn Phe Cys Asn Glu Arg Phe Thr His Leu 105 110 115 CCG GAG CCT GGG GGC CCA GAA GTC ACG TAC GAG CCA CCC CCG ACA GCC 439 Pro Glu Pro Gly Gly Pro Glu Val Thr Tyr Glu Pro Pro Pro Thr Ala 120 125 130 CCC ACC CTG CTC ACG GTG CTG GCC TAC TCG CTG CTG CCC ATT GGA GGC 487 wu w/Zu3a PCT/US98/09519 56 Pro Thr Leu Leu Thr Val Leu Ala Tyr Ser Leu Leu Pro Ile Gly Gly 135 140 145 CTC TCT CTC ATC GTC CTG CTG GCC TTC TGG ATG TAT CGT CAT CGG AAA 535 Leu Ser Leu Ile Val Leu Leu Ala Phe Trp Met Tyr Arg His Arg Lys 150 155 160 CCT CCC TAC GGC CAT GTG GAC ATC CAT GAG GAC CCG GGG CCT CCG CCC 583 Pro Pro Tyr Gly His Val Asp Ile His Glu Asp Pro Gly Pro Pro Pro 165 170 175 180 CCA TCC CCT CTG GTG GGC CTG AAG CCA CTA CAG CTG CTG GAG ATC AAG 631 Pro Ser Pro Leu Val Gly Leu Lys Pro Leu Gln Leu Leu Glu Ile Lys 185 190 195 GCT CGG GGC CGC TTT GGC TGC GTT TGG AAG GCT CAG CTC ATG AAC GAC 679 Ala Arg Gly Arg Phe Gly Cys Val Trp Lys Ala Gln Leu Met Asn Asp 200 205 210 TTT GTG GCT GTG AAG ATC TTC CCA CTT CAG GAC AAG CAG TCG TGG CAG 727 Phe Val Ala Val Lys Ile Phe Pro Leu Gln Asp Lys Gln Ser Trp Gln 215 220 225 AGT GAA CGG GAA ATC TTC AGC ACA CCC GGC ATG AAG CAC GAA AAC TTG 775 Ser Glu Arg Glu Ile Phe Ser Thr Pro Gly Met Lys His Glu Asn Leu 230 235 240 TTG CAG TTC ATT GCT GCC GAG AAA CGA GGC TCC AAC CTG GAG GTG GAG 823 Leu Gln Phe Ile Ala Ala Glu Lys Arg Gly Ser Asn Leu Glu Val Glu 245 250 255 260 CTG TGG CTC ATC ACA GCC TTC CAC GAC AAG GGC TCC CTC ACG GAT TAC 871 Leu Trp Leu Ile Thr Ala Phe His Asp Lys Gly Ser Leu Thr Asp Tyr 265 270 275 CTC AAG GGG AAC ATC ATC ACG TGG AAC GAA CTG TGC CAC GTG GCG GAG 919 Leu Lys Gly Asn Ile Ile Thr Trp Asn Glu Leu Cys His Val Ala Glu 280 285 290 ACG ATG TCA CGA GGC CTC TCA TAC CTG CAT GAG GAT GTG CCG TGG TGT 967 Thr Met Ser Arg Gly Leu Ser Tyr Leu His Glu Asp Val Pro Trp Cys 295 300 305 CGT GGT GAG GGC CAC AAG CCT TCT ATT GCC CAC AGG GAC TTC AAA AGC 1015 Arg Gly Glu Gly His Lys Pro Ser Ile Ala His Arg Asp Phe Lys Ser 310 315 320 AAG AAT GTA CTG CTG AAG AGC GAC CTC ACC GCG GTG CTG GCT GAC TTC 1063 Lys Asn Val Leu Leu Lys Ser Asp Leu Thr Ala Val Leu Ala Asp Phe 325 330 335 340 GGC CTG GCT GTT CGG TTT GAG CCA GGG AAG CCT CCT GGG GAT ACC CAT 1111 Gly Leu Ala Val Arg Phe Glu Pro Gly Lys Pro Pro Gly Asp Thr His 345 350 355 GGA CAG GTT GGC ACC AGA CGG TAC ATG GCC CCT GAG GTG CTG GAA GGA 1159 wU 9JI/.zU5 PCT/US98/09519 57 Gly Gln Val Gly Thr Arg Arg Tyr Met Ala Pro Glu Val Leu Glu Gly 360 365 370 GCC ATC AAC TTC CAG AGA GAC GCC TTC CTG CGT ATC GAC ATG TAC GCC 1207 Ala Ile Asn Phe Gln Arg Asp Ala Phe Leu Arg Ile Asp Met Tyr Ala 375 380 385 ATG GGC CTG GTG CTG TGG GAG CTC GTC TCT CGG TGC AAG GCT GCA GAC 1255 Met Gly Leu Val Leu Trp Glu Leu Val Ser Arg Cys Lys Ala Ala Asp 390 395 400 GGG CCT GTC GAT GAG TAC ATG CTG CCC TTC GAG GAG GAG ATT GGC CAG 1303 Gly Pro Val Asp Glu Tyr Met Leu Pro Phe Glu Glu Glu Ile Gly Gln 405 410 415 420 CAC CCT TCG CTG GAG GAG CTT CAG GAG GTG GTT GTC CAC AAG AAG ATG 1351 His Pro Ser Leu Glu Glu Leu Gln Glu Val Val Val His Lys Lys Met 425 430 435 AGG CCC ACG ATT AAG GAT CAC TGG CTG AAA CAC CCG GGC CTG GCC CAG 1399 Arg Pro Thr Ile Lys Asp His Trp Leu Lys His Pro Gly Leu Ala Gln 440 445 450 CTC TGC GTG ACC ATC GAG GAG TGC TGG GAC CAT GAT GCA GAG GCT CGC 1447 Leu Cys Val Thr Ile Glu Glu Cys Trp Asp His Asp Ala Glu Ala Arg 455 460 465 CTT TCT GCA GGC TGT GTA GAA GAG CGG GTA TCC CTG ATC AGG AGG TCG 1495 Leu Ser Ala Gly Cys Val Glu Glu Arg Val Ser Leu Ile Arg Arg Ser 470 475 480 GTC AAC GGC ACT ACC TCG GAC TGT CTC GTC TCT CTG GTG ACC TCC GTC 1543 Val Asn Gly Thr Thr Ser Asp Cys Leu Val Ser Leu Val Thr Ser Val 485 490 495 500 ACC AAT GTG GAC CTG CTC CCT AAA GAG TCC AGC ATC TAA GCCCGGGACA 1592 Thr Asn Val Asp Leu Leu Pro Lys Glu Ser Ser Ile * 505 510 CGTAGCGTCT CTCCAGACTC AGTGGATCTG AAGAAAAAAA AAAGTAAACC GTACTCCAA 1651 (2) INFORMATION FOR SEQ ID NO:4: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 513 amino acids (B) TYPE: amino acid (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (xi) SEQUENCE DESCRIPTION: SEQ ID NO:4: Met Thr Ala Pro Trp Ala Ala Leu Ala Leu Leu Trp Gly Ser Leu Cys 1 5 10 15 Ala Gly Ser Gly Arg Gly Glu Ala Glu Thr Arg Glu Cys Ile Tyr Tyr wu a/ZUo PCT/US98/09519 58 20 25 30 Asn Ala Asn Trp Glu Leu Glu Arg Thr Asn Gln Ser Gly Leu Glu Arg 35 40 45 Cys Glu Gly Glu Gln Asp Lys Arg Leu His Cys Tyr Ala Ser Trp Arg 50 55 60 Asn Ser Ser Gly Thr Ile Glu Leu Val Lys Lys Gly Cys Trp Leu Asp 65 70 75 80 Asp Phe Asn Cys Tyr Asp Arg Gln Glu Cys Val Ala Thr Glu Glu Asn 85 90 95 Pro Gln Val Tyr Phe Cys Cys Cys Glu Gly Asn Phe Cys Asn Glu Arg 100 105 110 Phe Thr His Leu Pro Glu Pro Gly Gly Pro Glu Val Thr Tyr Glu Pro 115 120 125 Pro Pro Thr Ala Pro Thr Leu Leu Thr Val Leu Ala Tyr Ser Leu Leu 130 135 140 Pro Ile Gly Gly Leu Ser Leu Ile Val Leu Leu Ala Phe Trp Met Tyr 145 150 155 160 Arg His Arg Lys Pro Pro Tyr Gly His Val Asp Ile His Glu Asp Pro 165 170 175 Gly Pro Pro Pro Pro Ser Pro Leu Val Gly Leu Lys Pro Leu Gln Leu 180 185 190 Leu Glu Ile Lys Ala Arg Gly Arg Phe Gly Cys Val Trp Lys Ala Gln 195 200 205 Leu Met Asn Asp Phe Val Ala Val Lys Ile Phe Pro Leu Gln Asp Lys 210 215 220 Gln Ser Trp Gln Ser Glu Arg Glu Ile Phe Ser Thr Pro Gly Met Lys 225 230 235 240 His Glu Asn Leu Leu Gln Phe Ile Ala Ala Glu Lys Arg Gly Ser Asn 245 250 255 Leu Glu Val Glu Leu Trp Leu Ile Thr Ala Phe His Asp Lys Gly Ser 260 265 270 Leu Thr Asp Tyr Leu Lys Gly Asn Ile Ile Thr Trp Asn Glu Leu Cys 275 280 285 His Val Ala Glu Thr Met Ser Arg Gly Leu Ser Tyr Leu His Glu Asp 290 295 300 Val Pro Trp Cys Arg Gly Glu Gly His Lys Pro Ser Ile Ala His Arg 305 310 315 320 WO 98/52US8 PCT/US98/09519 59 Asp Phe Lys Ser Lys Asn Val Leu Leu Lys Ser Asp Leu Thr Ala Val 325 330 335 Leu Ala Asp Phe Gly Leu Ala Val Arg Phe Glu Pro Gly Lys Pro Pro 340 345 350 Gly Asp Thr His Gly Gln Val Gly Thr Arg Arg Tyr Met Ala Pro Glu 355 360 365 Val Leu Glu Gly Ala Ile Asn Phe Gln Arg Asp Ala Phe Leu Arg Ile 370 375 380 Asp Met Tyr Ala Met Gly Leu Val Leu Trp Glu Leu Val Ser Arg Cys 385 390 395 400 Lys Ala Ala Asp Gly Pro Val Asp Glu Tyr Met Leu Pro Phe Glu Glu 405 410 415 Glu Ile Gly Gln His Pro Ser Leu Glu Glu Leu Gln Glu Val Val Val 420 425 430 His Lys Lys Met Arg Pro Thr Ile Lys Asp His Trp Leu Lys His Pro 435 440 445 Gly Leu Ala Gln Leu Cys Val Thr Ile Glu Glu Cys Trp Asp His Asp 450 455 460 Ala Glu Ala Arg Leu Ser Ala Gly Cys Val Glu Glu Arg Val Ser Leu 465 470 475 480 Ile Arg Arg Ser Val Asn Gly Thr Thr Ser Asp Cys Leu Val Ser Leu 485 490 495 Val Thr Ser Val Thr Asn Val Asp Leu Leu Pro Lys Glu Ser Ser Ile 500 505 510 Wo 98/W~2US8 PCT/US98/09519 60 (2) INFORMATION FOR SEQ ID NO:5: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 1699 base pairs (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: DNA (genomic) (ix) FEATURE: (A) NAME/KEY: CDS (B) LOCATION: 44..1630 (xi) SEQUENCE DESCRIPTION: SEQ ID NO:5: CCCTGCCCGC GGGCTCCGGG TGTCGCGGGG CGCGCCGCGG AAC ATG ACG GCG CCC 55 Met Thr Ala Pro 1 TGG GCG GCC CTC GCC CTT CTC TGG GGA TCG CTG TGC GCC GGT TCC GGG 103 Trp Ala Ala Leu Ala Leu Leu Trp Gly Ser Leu Cys Ala Gly Ser Gly 5 10 15 20 CGA GGG GAG GCT GAG ACT CGG GAG TGC ATC TAC TAC AAC GCC AAC TGG 151 Arg Gly Glu Ala Glu Thr Arg Glu Cys Ile Tyr Tyr Asn Ala Asn Trp 25 30 35 GAG CTG GAG CGC ACC AAC CAG AGC GGC CTG GAG CGC TGC GAG GGG GAA 199 Glu Leu Glu Arg Thr Asn Gln Ser Gly Leu Glu Arg Cys Glu Gly Glu 40 45 50 CAG GAC AAG CGG CTG CAC TGC TAC GCC TCG TGG CGC AAC AGC TCG GGC 247 Gln Asp Lys Arg Leu His Cys Tyr Ala Ser Trp Arg Asn Ser Ser Gly 55 60 65 ACC ATC GAG CTG GTG AAG AAG GGC TGC TGG CTA GAT GAC TTC AAT TGC 295 Thr Ile Glu Leu Val Lys Lys Gly Cys Trp Leu Asp Asp Phe Asn Cys 70 75 80 TAC GAC AGG CAG GAG TGT GTG GCC ACC GAG GAG AAC CCC CAG GTG TAC 343 Tyr Asp Arg Gln Glu Cys Val Ala Thr Glu Glu Asn Pro Gln Val Tyr 85 90 95 100 TTC TGC TGC TGC GAA GGC AAC TTC TGC AAC GAG CGC TTC ACC CAC TTG 391 Phe Cys Cys Cys Glu Gly Asn Phe Cys Asn Glu Arg Phe Thr His Leu 105 110 115 CCG GAG CCT GGG GGC CCA GAA GCC CCC ACC CTG CTC ACG GTG CTG GCC 439 Pro Glu Pro Gly Gly Pro Glu Ala Pro Thr Leu Leu Thr Val Leu Ala 120 125 130 TAC TCG CTG CTG CCC ATT GGA GGC CTC TCT CTC ATC GTC CTG CTG GCC 487 Tyr Ser Leu Leu Pro Ile Gly Gly Leu Ser Leu Ile Val Leu Leu Ala wYuyo/muoo u'T/U595/U9519 61 135 140 145 TTC TGG ATG TAT CGT CAT CGG AAA CCT CCC TAC GGC CAT GTG GAC ATC 535 Phe Trp Met Tyr Arg His Arg Lys Pro Pro Tyr Gly His Val Asp Ile 150 155 160 CAT GAG GTG AGA CAG TGC CAG CGT TGG GCA GGG AGA AGG GAC GGC TGT 583 His Glu Val Arg Gln Cys Gln Arg Trp Ala Gly Arg Arg Asp Gly Cys 165 170 175 180 GCG GAC TCC TTT AAG CCC TTG CCT TTC CAG GAC CCG GGG CCT CCG CCC 631 Ala Asp Ser Phe Lys Pro Leu Pro Phe Gln Asp Pro Gly Pro Pro Pro 185 190 195 CCA TCC CCT CTG GTG GGC CTG AAG CCA CTA CAG CTG CTG GAG ATC AAG 679 Pro Ser Pro Leu Val Gly Leu Lys Pro Leu Gln Leu Leu Glu Ile Lys 200 205 210 GCT CGG GGC CGC TTT GGC TGC GTT TGG AAG GCT CAG CTC ATG AAC GAC 727 Ala Arg Gly Arg Phe Gly Cys Val Trp Lys Ala Gln Leu Met Asn Asp 215 220 225 TTT GTG GCT GTG AAG ATC TTC CCA CTT CAG GAC AAG CAG TCG TGG CAG 775 Phe Val Ala Val Lys Ile Phe Pro Leu Gln Asp Lys Gln Ser Trp Gln 230 235 240 AGT GAA CGG GAA ATC TTC AGC ACA CCC GGC ATG AAG CAC GAA AAC TTG 823 Ser Glu Arg Glu Ile Phe Ser Thr Pro Gly Met Lys His Glu Asn Leu 245 250 255 260 TTG CAG TTC ATT GCT GCC GAG AAA CGA GGC TCC AAC CTG GAG GTG GAG 871 Leu Gln Phe Ile Ala Ala Glu Lys Arg Gly Ser Asn Leu Glu Val Glu 265 270 275 CTG TGG CTC ATC ACA GCC TTC CAC GAC AAG GGC TCC CTC ACG GAT TAC 919 Leu Trp Leu Ile Thr Ala Phe His Asp Lys Gly Ser Leu Thr Asp Tyr 280 285 290 CTC AAG GGG AAC ATC ATC ACG TGG AAC GAA CTG TGC CAC GTG GCG GAG 967 Leu Lys Gly Asn Ile Ile Thr Trp Asn Glu Leu Cys His Val Ala Glu 295 300 305 ACG ATG TCA CGA GGC CTC TCA TAC CTG CAT GAG GAT GTG CCG TGG TGT 1015 Thr Met Ser Arg Gly Leu Ser Tyr Leu His Glu Asp Val Pro Trp Cys 310 315 320 CGT GGT GAG GGC CAC AAG CCT TCT ATT GCC CAC AGG GAC TTC AAA AGC 1063 Arg Gly Glu Gly His Lys Pro Ser Ile Ala His Arg Asp Phe Lys Ser 325 330 335 340 AAG AAT GTA CTG CTG AAG AGC GAC CTC ACC GCG GTG CTG GCT GAC TTC 111iii1 Lys Asn Val Leu Leu Lys Ser Asp Leu Thr Ala Val Leu Ala Asp Phe 345 350 355 GGC CTG GCT GTT CGG TTT GAG CCA GGG AAG CCT CCT GGG GAT ACC CAT 1159 Gly Leu Ala Val Arg Phe Glu Pro Gly Lys Pro Pro Gly Asp Thr His wo 95/2UJu PCT/US98/09519 62 360 365 370 GGA CAG GTT GGC ACC AGA CGG TAC ATG GCC CCT GAG GTG CTG GAA GGA 1207 Gly Gln Val Gly Thr Arg Arg Tyr Met Ala Pro Glu Val Leu Glu Gly 375 380 385 GCC ATC AAC TTC CAG AGA GAC GCC TTC CTG CGT ATC GAC ATG TAC GCC 1255 Ala Ile Asn Phe Gln Arg Asp Ala Phe Leu Arg Ile Asp Met Tyr Ala 390 395 400 ATG GGC CTG GTG CTG TGG GAG CTC GTC TCT CGG TGC AAG GCT GCA GAC 1303 Met Gly Leu Val Leu Trp Glu Leu Val Ser Arg Cys Lys Ala Ala Asp 405 410 415 420 GGG CCT GTC GAT GAG TAC ATG CTG CCC TTC GAG GAG GAG ATT GGC CAG 1351 Gly Pro Val Asp Glu Tyr Met Leu Pro Phe Glu Glu Glu Ile Gly Gln 425 430 435 CAC CCT TCG CTG GAG GAG CTT CAG GAG GTG GTT GTC CAC AAG AAG ATG 1399 His Pro Ser Leu Glu Glu Leu Gln Glu Val Val Val His Lys Lys Met 440 445 450 AGG CCC ACG ATT AAG GAT CAC TGG CTG AAA CAC CCG GGC CTG GCC CAG 1447 Arg Pro Thr Ile Lys Asp His Trp Leu Lys His Pro Gly Leu Ala Gln 455 460 465 CTC TGC GTG ACC ATC GAG GAG TGC TGG GAC CAT GAT GCA GAG GCT CGC 1495 Leu Cys Val Thr Ile Glu Glu Cys Trp Asp His Asp Ala Glu Ala Arg 470 475 480 CTT TCT GCA GGC TGT GTA GAA GAG CGG GTA TCC CTG ATC AGG AGG TCG 1543 Leu Ser Ala Gly Cys Val Glu Glu Arg Val Ser Leu Ile Arg Arg Ser 485 490 495 500 GTC AAC GGC ACT ACC TCG GAC TGT CTC GTC TCT CTG GTG ACC TCC GTC 1591 Val Asn Gly Thr Thr Ser Asp Cys Leu Val Ser Leu Val Thr Ser Val 505 510 515 ACC AAT GTG GAC CTG CTC CCT AAA GAG TCC AGC ATC TAA GCCCGGGACA 1640 Thr Asn Val Asp Leu Leu Pro Lys Glu Ser Ser Ile * 520 525 CGTAGCGTCT CTCCAGACTC AGTGGATCTG AAGAAAAAAA AAAGTAAACC GTACTCCAA 1699 (2) INFORMATION FOR SEQ ID NO:6: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 529 amino acids (B) TYPE: amino acid (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (xi) SEQUENCE DESCRIPTION: SEQ ID NO:6: WU 9Yi/UJS PCT/US98/09519 63 Met Thr Ala Pro Trp Ala Ala Leu Ala Leu Leu Trp Gly Ser Leu Cys 1 5 10 15 Ala Gly Ser Gly Arg Gly Glu Ala Glu Thr Arg Glu Cys Ile Tyr Tyr 20 25 30 Asn Ala Asn Trp Glu Leu Glu Arg Thr Asn Gln Ser Gly Leu Glu Arg 35 40 45 Cys Glu Gly Glu Gln Asp Lys Arg Leu His Cys Tyr Ala Ser Trp Arg 50 55 60 Asn Ser Ser Gly Thr Ile Glu Leu Val Lys Lys Gly Cys Trp Leu Asp 65 70 75 80 Asp Phe Asn Cys Tyr Asp Arg Gln Glu Cys Val Ala Thr Glu Glu Asn 85 90 95 Pro Gln Val Tyr Phe Cys Cys Cys Glu Gly Asn Phe Cys Asn Glu Arg 100 105 110 Phe Thr His Leu Pro Glu Pro Gly Gly Pro Glu Ala Pro Thr Leu Leu 115 120 125 Thr Val Leu Ala Tyr Ser Leu Leu Pro Ile Gly Gly Leu Ser Leu Ile 130 135 140 Val Leu Leu Ala Phe Trp Met Tyr Arg His Arg Lys Pro Pro Tyr Gly 145 150 155 160 His Val Asp Ile His Glu Val Arg Gln Cys Gln Arg Trp Ala Gly Arg 165 170 175 Arg Asp Gly Cys Ala Asp Ser Phe Lys Pro Leu Pro Phe Gln Asp Pro 180 185 190 Gly Pro Pro Pro Pro Ser Pro Leu Val Gly Leu Lys Pro Leu Gln Leu 195 200 205 Leu Glu Ile Lys Ala Arg Gly Arg Phe Gly Cys Val Trp Lys Ala Gln 210 215 220 Leu Met Asn Asp Phe Val Ala Val Lys Ile Phe Pro Leu Gln Asp Lys 225 230 235 240 Gln Ser Trp Gln Ser Glu Arg Glu Ile Phe Ser Thr Pro Gly Met Lys 245 250 255 His Glu Asn Leu Leu Gln Phe Ile Ala Ala Glu Lys Arg Gly Ser Asn 260 265 270 Leu Glu Val Glu Leu Trp Leu Ile Thr Ala Phe His Asp Lys Gly Ser 275 280 285 Leu Thr Asp Tyr Leu Lys Gly Asn Ile Ile Thr Trp Asn Glu Leu Cys 290 295 300 wo 9YiSAUS PCT/US98/09519 64 His Val Ala Glu Thr Met Ser Arg Gly Leu Ser Tyr Leu His Glu Asp 305 310 315 320 Val Pro Trp Cys Arg Gly Glu Gly His Lys Pro Ser Ile Ala His Arg 325 330 335 Asp Phe Lys Ser Lys Asn Val Leu Leu Lys Ser Asp Leu Thr Ala Val 340 345 350 Leu Ala Asp Phe Gly Leu Ala Val Arg Phe Glu Pro Gly Lys Pro Pro 355 360 365 Gly Asp Thr His Gly Gln Val Gly Thr Arg Arg Tyr Met Ala Pro Glu 370 375 380 Val Leu Glu Gly Ala Ile Asn Phe Gln Arg Asp Ala Phe Leu Arg Ile 385 390 395 400 Asp Met Tyr Ala Met Gly Leu Val Leu Trp Glu Leu Val Ser Arg Cys 405 410 415 Lys Ala Ala Asp Gly Pro Val Asp Glu Tyr Met Leu Pro Phe Glu Glu 420 425 430 Glu Ile Gly Gln His Pro Ser Leu Glu Glu Leu Gln Glu Val Val Val 435 440 445 His Lys Lys Met Arg Pro Thr Ile Lys Asp His Trp Leu Lys His Pro 450 455 460 Gly Leu Ala Gln Leu Cys Val Thr Ile Glu Glu Cys Trp Asp His Asp 465 470 475 480 Ala Glu Ala Arg Leu Ser Ala Gly Cys Val Glu Glu Arg Val Ser Leu 485 490 495 Ile Arg Arg Ser Val Asn Gly Thr Thr Ser Asp Cys Leu Val Ser Leu 500 505 510 Val Thr Ser Val Thr Asn Val Asp Leu Leu Pro Lys Glu Ser Ser Ile 515 520 525 . (2) INFORMATION FOR SEQ ID NO:7: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 1628 base pairs (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (ii) MOLECULE TYPE: DNA (genomic) wu 95t/wIU. PCUT/US98/09519 65 (ix) FEATURE: (A) NAME/KEY: CDS (B) LOCATION: 44..1558 (xi) SEQUENCE DESCRIPTION: SEQ ID NO:7: CCCTGCCCGC GGGCTCCGGG TGTCGCGGGG CGCGCCGCGG AAC ATG ACG GCG CCC 55 Met Thr Ala Pro 1 TGG GCG GCC CTC GCC CTT CTC TGG GGA TCG CTG TGC GCC GGT TCC GGG 103 Trp Ala Ala Leu Ala Leu Leu Trp Gly Ser Leu Cys Ala Gly Ser Gly 5 10 15 20 CGA GGG GAG GCT GAG ACT CGG GAG TGC ATC TAC TAC AAC GCC AAC TGG 151 Arg Gly Glu Ala Glu Thr Arg Glu Cys Ile Tyr Tyr Asn Ala Asn Trp 25 30 35 GAG CTG GAG CGC ACC AAC CAG AGC GGC CTG GAG CGC TGC GAG GGG GAA 199 Glu Leu Glu Arg Thr Asn Gln Ser Gly Leu Glu Arg Cys Glu Gly Glu 40 45 50 CAG GAC AAG CGG CTG CAC TGC TAC GCC TCG TGG CGC AAC AGC TCG GGC 247 Gln Asp Lys Arg Leu His Cys Tyr Ala Ser Trp Arg Asn Ser Ser Gly 55 60 65 ACC ATC GAG CTG GTG AAG AAG GGC TGC TGG CTA GAT GAC TTC AAT TGC 295 Thr Ile Glu Leu Val Lys Lys Gly Cys Trp Leu Asp Asp Phe Asn Cys 70 75 80 TAC GAC AGG CAG GAG TGT GTG GCC ACC GAG GAG AAC CCC CAG GTG TAC 343 Tyr Asp Arg Gln Glu Cys Val Ala Thr Glu Glu Asn Pro Gln Val Tyr 85 90 95 100 TTC TGC TGC TGC GAA GGC AAC TTC TGC AAC GAG CGC TTC ACC CAC TTG 391 Phe Cys Cys Cys Glu Gly Asn Phe Cys Asn Glu Arg Phe Thr His Leu 105 110 115 CCG GAG CCT GGG GGC CCA GAA GCC CCC ACC CTG CTC ACG GTG CTG GCC 439 Pro Glu Pro Gly Gly Pro Glu Ala Pro Thr Leu Leu Thr Val Leu Ala 120 125 130 TAC TCG CTG CTG CCC ATT GGA GGC CTC TCT CTC ATC GTC CTG CTG GCC 487 Tyr Ser Leu Leu Pro Ile Gly Gly Leu Ser Leu Ile Val Leu Leu Ala 135 140 145 TTC TGG ATG TAT CGT CAT CGG AAA CCT CCC TAC GGC CAT GTG GAC ATC 535 Phe Trp Met Tyr Arg His Arg Lys Pro Pro Tyr Gly His Val Asp Ile 150 155 160 CAT GAG GAC CCG GGG CCT CCG CCC CCA TCC CCT CTG GTG GGC CTG AAG 583 His Glu Asp Pro Gly Pro Pro Pro Pro Ser Pro Leu Val Gly Leu Lys 165 170 175 180 CCA CTA CAG CTG CTG GAG ATC AAG GCT CGG GGC CGC TTT GGC TGC GTT 631 WO 98/52U038 PCT/US98/09519 66 Pro Leu Gln Leu Leu Glu Ile Lys Ala Arg Gly Arg Phe Gly Cys Val 185 190 195 TGG AAG GCT CAG CTC ATG AAC GAC TTT GTG GCT GTG AAG ATC TTC CCA 679 Trp Lys Ala Gln Leu Met Asn Asp Phe Val Ala Val Lys Ile Phe Pro 200 205 210 CTT CAG GAC AAG CAG TCG TGG CAG AGT GAA CGG GAA ATC TTC AGC ACA 727 Leu Gln Asp Lys Gln Ser Trp Gln Ser Glu Arg Glu Ile Phe Ser Thr 215 220 225 CCC GGC ATG AAG CAC GAA AAC TTG TTG CAG TTC ATT GCT GCC GAG AAA 775 Pro Gly Met Lys His Glu Asn Leu Leu Gln Phe Ile Ala Ala Glu Lys 230 235 240 CGA GGC TCC AAC CTG GAG GTG GAG CTG TGG CTC ATC ACA GCC TTC CAC 823 Arg Gly Ser Asn Leu Glu Val Glu Leu Trp Leu Ile Thr Ala Phe His 245 250 255 260 GAC AAG GGC TCC CTC ACG GAT TAC CTC AAG GGG AAC ATC ATC ACG TGG 871 Asp Lys Gly Ser Leu Thr Asp Tyr Leu Lys Gly Asn Ile Ile Thr Trp 265 270 275 AAC GAA CTG TGC CAC GTG GCG GAG ACG ATG TCA CGA GGC CTC TCA TAC 919 Asn Glu Leu Cys His Val Ala Glu Thr Met Ser Arg Gly Leu Ser Tyr 280 285 290 CTG CAT GAG GAT GTG CCG TGG TGT CGT GGT GAG GGC CAC AAG CCT TCT 967 Leu His Glu Asp Val Pro Trp Cys Arg Gly Glu Gly His Lys Pro Ser 295 300 305 ATT GCC CAC AGG GAC TTC AAA AGC AAG AAT GTA CTG CTG AAG AGC GAC 1015 Ile Ala His Arg Asp Phe Lys Ser Lys Asn Val Leu Leu Lys Ser Asp 310 315 320 CTC ACC GCG GTG CTG GCT GAC TTC GGC CTG GCT GTT CGG TTT GAG CCA 1063 Leu Thr Ala Val Leu Ala Asp Phe Gly Leu Ala Val Arg Phe Glu Pro 325 330 335 340 GGG AAG CCT CCT GGG GAT ACC CAT GGA CAG GTT GGC ACC AGA CGG TAC 111iii Gly Lys Pro Pro Gly Asp Thr His Gly Gln Val Gly Thr Arg Arg Tyr 345 350 355 ATG GCC CCT GAG GTG CTG GAA GGA GCC ATC AAC TTC CAG AGA GAC GCC 1159 Met Ala Pro Glu Val Leu Glu Gly Ala Ile Asn Phe Gln Arg Asp Ala 360 365 370 TTC CTG CGT ATC GAC ATG TAC GCC ATG GGC CTG GTG CTG TGG GAG CTC 1207 Phe Leu Arg Ile Asp Met Tyr Ala Met Gly Leu Val Leu Trp Glu Leu 375 380 385 GTC TCT CGG TGC AAG GCT GCA GAC GGG CCT GTC GAT GAG TAC ATG CTG 1255 Val Ser Arg Cys Lys Ala Ala Asp Gly Pro Val Asp Glu Tyr Met Leu 390 395 400 CCC TTC GAG GAG GAG ATT GGC CAG CAC CCT TCG CTG GAG GAG CTT CAG 1303 WO 98/52038 PCT/US98/09519 67 Pro Phe Glu Glu Glu Ile Gly Gln His Pro Ser Leu Glu Glu Leu Gln 405 410 415 420 GAG GTG GTT GTC CAC AAG AAG ATG AGG CCC ACG ATT AAG GAT CAC TGG 1351 Glu Val Val Val His Lys Lys Met Arg Pro Thr Ile Lys Asp His Trp 425 430 435 CTG AAA CAC CCG GGC CTG GCC CAG CTC TGC GTG ACC ATC GAG GAG TGC 1399 Leu Lys His Pro Gly Leu Ala Gln Leu Cys Val Thr Ile Glu Glu Cys 440 445 450 TGG GAC CAT GAT GCA GAG GCT CGC CTT TCT GCA GGC TGT GTA GAA GAG 1447 Trp Asp His Asp Ala Glu Ala Arg Leu Ser Ala Gly Cys Val Glu Glu 455 460 465 CGG GTA TCC CTG ATC AGG AGG TCG GTC AAC GGC ACT ACC TCG GAC TGT 1495 Arg Val Ser Leu Ile Arg Arg Ser Val Asn Gly Thr Thr Ser Asp Cys 470 475 480 CTC GTC TCT CTG GTG ACC TCC GTC ACC AAT GTG GAC CTG CTC CCT AAA 1543 Leu Val Ser Leu Val Thr Ser Val Thr Asn Val Asp Leu Leu Pro Lys 485 490 495 500 GAG TCC AGC ATC TAA GCCCGGGACA CGTAGCGTCT CTCCAGACTC AGTGGATCTG 1598 Glu Ser Ser Ile * 505 AAGAAAAAAA AAAGTAAACA CGTACTCCAA 1628 (2) INFORMATION FOR SEQ ID NO:8: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 505 amino acids (B) TYPE: amino acid (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (xi) SEQUENCE DESCRIPTION: SEQ ID NO:8: Met Thr Ala Pro Trp Ala Ala Leu Ala Leu Leu Trp Gly Ser Leu Cys 1 5 10 15 Ala Gly Ser Gly Arg Gly Glu Ala Glu Thr Arg Glu Cys Ile Tyr Tyr 20 25 30 Asn Ala Asn Trp Glu Leu Glu Arg Thr Asn Gln Ser Gly Leu Glu Arg 35 40 45 Cys Glu Gly Glu Gln Asp Lys Arg Leu His Cys Tyr Ala Ser Trp Arg 50 55 60 Asn Ser Ser Gly Thr Ile Glu Leu Val Lys Lys Gly Cys Trp Leu Asp 65 70 75 80 Wu 9/bZUJ~S PCT/US98/09519 68 Asp Phe Asn Cys Tyr Asp Arg Gln Glu Cys Val Ala Thr Glu Glu Asn 85 90 95 Pro Gln Val Tyr Phe Cys Cys Cys Glu Gly Asn Phe Cys Asn Glu Arg 100 105 110 Phe Thr His Leu Pro Glu Pro Gly Gly Pro Glu Ala Pro Thr Leu Leu 115 120 125 Thr Val Leu Ala Tyr Ser Leu Leu Pro Ile Gly Gly Leu Ser Leu Ile 130 135 140 Val Leu Leu Ala Phe Trp Met Tyr Arg His Arg Lys Pro Pro Tyr Gly 145 150 155 160 His Val Asp Ile His Glu Asp Pro Gly Pro Pro Pro Pro Ser Pro Leu 165 170 175 Val Gly Leu Lys Pro Leu Gln Leu Leu Glu Ile Lys Ala Arg Gly Arg 180 185 190 Phe Gly Cys Val Trp Lys Ala Gln Leu Met Asn Asp Phe Val Ala Val 195 200 205 Lys Ile Phe Pro Leu Gln Asp Lys Gln Ser Trp Gln Ser Glu Arg Glu 210 215 220 Ile Phe Ser Thr Pro Gly Met Lys His Glu Asn Leu Leu Gln Phe Ile 225 230 235 240 Ala Ala Glu Lys Arg Gly Ser Asn Leu Glu Val Glu Leu Trp Leu Ile 245 250 255 Thr Ala Phe His Asp Lys Gly Ser Leu Thr Asp Tyr Leu Lys Gly Asn 260 265 270 Ile Ile Thr Trp Asn Glu Leu Cys His Val Ala Glu Thr Met Ser Arg 275 280 285 Gly Leu Ser Tyr Leu His Glu Asp Val Pro Trp Cys Arg Gly Glu Gly 290 295 300 His Lys Pro Ser Ile Ala His Arg Asp Phe Lys Ser Lys Asn Val Leu 305 310 315 320 Leu Lys Ser Asp Leu Thr Ala Val Leu Ala Asp Phe Gly Leu Ala Val 325 330 335 Arg Phe Glu Pro Gly Lys Pro Pro Gly Asp Thr His Gly Gln Val Gly 340 345 350 Thr Arg Arg Tyr Met Ala Pro Glu Val Leu Glu Gly Ala Ile Asn Phe 355 360 365 Gln Arg Asp Ala Phe Leu Arg Ile Asp Met Tyr Ala Met Gly Leu Val 370 375 380 WO 98/52ujS PCT/US98/09519 69 Leu Trp Glu Leu Val Ser Arg Cys Lys Ala Ala Asp Gly Pro Val Asp 385 390 395 400 Glu Tyr Met Leu Pro Phe Glu Glu Glu Ile Gly Gln His Pro Ser Leu 405 410 415 Glu Glu Leu Gln Glu Val Val Val His Lys Lys Met Arg Pro Thr Ile 420 425 430 Lys Asp His Trp Leu Lys His Pro Gly Leu Ala Gln Leu Cys Val Thr 435 440 445 Ile Glu Glu Cys Trp Asp His Asp Ala Glu Ala Arg Leu Ser Ala Gly 450 455 460 Cys Val Glu Glu Arg Val Ser Leu Ile Arg Arg Ser Val Asn Gly Thr 465 470 475 480 Thr Ser Asp Cys Leu Val Ser Leu Val Thr Ser Val Thr Asn Val Asp 485 490 495 Leu Leu Pro Lys Glu Ser Ser Ile * 500 505 WU 9/52UJ53 FCT'IUS98/09519 70 (2) INFORMATION FOR SEQ ID NO:9: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 3601 base pairs (B) TYPE: nucleic acid (C) STRANDEDNESS: double (D) TOPOLOGY: linear (ii) MOLECULE TYPE: cDNA (ix) FEATURE: (A) NAME/KEY: CDS (B) LOCATION: join(409..3522) (xi) SEQUENCE DESCRIPTION: SEQ ID NO:9: CGCCCCCCGA CCCCGGATCG AATCCCCGCC CTCCGCACCC TGGATATGTT TTCTCCCAGA 60 CCTGGATATT TTTTTGATAT CGTGAAACTA CGAGGGAAAT AATTTGGGGG ATTTCTTCTT 120 GGCTCCCTGC TTTCCCCACA GACATGCCTT CCGTTTGGAG GGCCGCGGCA CCCCGTCCGA 180 GGCGAAGGAA CCCCCCCAGC CGCGAGGGAG AGAAATGAAG GGAATTTCTG CAGCGGCATG 240 AAAGCTCTGC AGCTAGGTCC TCTCATCAGC CATTTGTCCT TTCAAACTGT ATTGTGATAC 300 GGGCAGGATC AGTCCACGGG AGAGAAGACG AGCCTCCCGG CTGTTTCTCC GCCGGTCTAC 360 TTCCCATATT TCTTTTCTTT GCCCTCCTGA TTCTTGGCTG GCCCAGGG ATG ACT TCC 417 Met Thr Ser 1 TCG CTG CAG CGG CCC TGG CGG GTG CCC TGG CTA CCA TGG ACC ATC CTG 465 Ser Leu Gln Arg Pro Trp Arg Val Pro Trp Leu Pro Trp Thr Ile Leu 5 10 15 CTG GTC AGC ACT GCG GCT GCT TCG CAG AAT CAA GAA CGG CTA TGT GCG 513 Leu Val Ser Thr Ala Ala Ala Ser Gln Asn Gln Glu Arg Leu Cys Ala 20 25 30 35 TTT AAA GAT CCG TAT CAG CAA GAC CTT GGG ATA GGT GAG AGT AGA ATC 561 Phe Lys Asp Pro Tyr Gln Gln Asp Leu Gly Ile Gly Glu Ser Arg Ile 40 45 50 TCT CAT GAA AAT GGG ACA ATA TTA TGC TCG AAA GGT AGC ACC TGC TAT 609 Ser His Glu Asn Gly Thr Ile Leu Cys Ser Lys Gly Ser Thr Cys Tyr 55 60 65 GGC CTT TGG GAG AAA TCA AAA GGG GAC ATA AAT CTT GTA AAA CAA GGA 657 Gly Leu Trp Glu Lys Ser Lys Gly Asp Ile Asn Leu Val Lys Gln Gly 70 75 80 TGT TGG TCT CAC ATT GGA GAT CCC CAA GAG TGT CAC TAT GAA GAA TGT 705 Cys Trp Ser His Ile Gly Asp Pro Gln Glu Cys His Tyr Glu Glu Cys WO 98/52038 PCT/US98/09519 71 85 90 95 GTA GTA ACT ACC ACT CCT CCC TCA ATT CAG AAT GGA ACA TAC CGT TTC 753 Val Val Thr Thr Thr Pro Pro Ser Ile Gln Asn Gly Thr Tyr Arg Phe 100 105 110 115 TGC TGT TGT AGC ACA GAT TTA TGT AAT GTC AAC TTT ACT GAG AAT TTT 801 Cys Cys Cys Ser Thr Asp Leu Cys Asn Val Asn Phe Thr Glu Asn Phe 120 125 130 CCA CCT CCT GAC ACA ACA CCA CTC AGT CCA CCT CAT TCA TTT AAC CGA 849 Pro Pro Pro Asp Thr Thr Pro Leu Ser Pro Pro His Ser Phe Asn Arg 135 140 145 GAT GAG ACA ATA ATC ATT GCT TTG GCA TCA GTC TCT GTA TTA GCT GTT 897 Asp Glu Thr Ile Ile Ile Ala Leu Ala Ser Val Ser Val Leu Ala Val 150 155 160 TTG ATA GTT GCC TTA TGC TTT GGA TAC AGA ATG TTG ACA GGA GAC CGT 945 Leu Ile Val Ala Leu Cys Phe Gly Tyr Arg Met Leu Thr Gly Asp Arg 165 170 175 AAA CAA GGT CTT CAC AGT ATG AAC ATG ATG GAG GCA GCA GCA TCC GAA 993 Lys Gln Gly Leu His Ser Met Asn Met Met Glu Ala Ala Ala Ser Glu 180 185 190 195 CCC TCT CTT GAT CTA GAT AAT CTG AAA CTG TTG GAG CTG ATT GGC CGA 1041 Pro Ser Leu Asp Leu Asp Asn Leu Lys Leu Leu Glu Leu Ile Gly Arg 200 205 210 GGT CGA TAT GGA GCA GTA TAT AAA GGC TCC TTG GAT GAG CGT CCA GTT 1089 Gly Arg Tyr Gly Ala Val Tyr Lys Gly Ser Leu Asp Glu Arg Pro Val 215 220 225 GCT GTA AAA GTG TTT TCC TTT GCA AAC CGT CAG AAT TTT ATC AAC GAA 1137 Ala Val Lys Val Phe Ser Phe Ala Asn Arg Gln Asn Phe Ile Asn Glu 230 235 240 AAG AAC ATT TAC AGA GTG CCT TTG ATG GAA CAT GAC AAC ATT GCC CGC 1185 Lys Asn Ile Tyr Arg Val Pro Leu Met Glu His Asp Asn Ile Ala Arg 245 250 255 TTT ATA GTT GGA GAT GAG AGA GTC ACT GCA GAT GGA CGC ATG GAA TAT 1233 Phe Ile Val Gly Asp Glu Arg Val Thr Ala Asp Gly Arg Met Glu Tyr 260 265 270 275 TTG CTT GTG ATG GAG TAC TAT CCC AAT GGA TCT TTA TGC AAG TAT TTA 1281 Leu Leu Val Met Glu Tyr Tyr Pro Asn Gly Ser Leu Cys Lys Tyr Leu 280 285 290 AGT CTC CAC ACA AGT GAC TGG GTA AGC TCT TGC CGT CTT GCT CAT TCT 1329 Ser Leu His Thr Ser Asp Trp Val Ser Ser Cys Arg Leu Ala His Ser 295 300 305 GTT ACT AGA GGA CTG GCT TAT CTT CAC ACA GAA TTA CCA CGA GGA GAT 1377 Val Thr Arg Gly Leu Ala Tyr Leu His Thr Glu Leu Pro Arg Gly Asp wu 98/U.M5 PCT/US98/09519 72 310 315 320 CAT TAT AAA CCT GCA ATT TCC CAT CGA GAT TTA AAC AGC AGA AAT GTC 1425 His Tyr Lys Pro Ala Ile Ser His Arg Asp Leu Asn Ser Arg Asn Val 325 330 335 CTA GTG AAA AAT GAT GGA ACC TGT GTT ATT AGT GAC TTT GGA CTG TCC 1473 Leu Val Lys Asn Asp Gly Thr Cys Val Ile Ser Asp Phe Gly Leu Ser 340 345 350 355 ATG AGG CTG ACT GGA AAT AGA CTG GTG CGC CCA GGG GAG GAA GAT AAT 1521 Met Arg Leu Thr Gly Asn Arg Leu Val Arg Pro Gly Glu Glu Asp Asn 360 365 370 GCA GCC ATA AGC GAG GTT GGC ACT ATC AGA TAT ATG GCA CCA GAA GTG 1569 Ala Ala Ile Ser Glu Val Gly Thr Ile Arg Tyr Met Ala Pro Glu Val 375 380 385 CTA GAA GGA GCT GTG AAC TTG AGG GAC TGT GAA TCA GCT TTG AAA CAA 1617 Leu Glu Gly Ala Val Asn Leu Arg Asp Cys Glu Ser Ala Leu Lys Gln 390 395 400 GTA GAC ATG TAT GCT CTT GGA CTA ATC TAT TGG GAG ATA TTT ATG AGA 1665 Val Asp Met Tyr Ala Leu Gly Leu Ile Tyr Trp Glu Ile Phe Met Arg 405 410 415 TGT ACA GAC CTC TTC CCA GGG GAA TCC GTA CCA GAG TAC CAG ATG GCT 1713 Cys Thr Asp Leu Phe Pro Gly Glu Ser Val Pro Glu Tyr Gln Met Ala 420 425 430 435 TTT CAG ACA GAG GTT GGA AAC CAT CCC ACT TTT GAG GAT ATG CAG GTT 1761 Phe Gln Thr Glu Val Gly Asn His Pro Thr Phe Glu Asp Met Gln Val 440 445 450 CTC GTG TCT AGG GAA AAA CAG AGA CCC AAG TTC CCA GAA GCC TGG AAA 1809 Leu Val Ser Arg Glu Lys Gln Arg Pro Lys Phe Pro Glu Ala Trp Lys 455 460 465 GAA AAT AGC CTG GCA GTG AGG TCA CTC AAG GAG ACA ATC GAA GAC TGT 1857 Glu Asn Ser Leu Ala Val Arg Ser Leu Lys Glu Thr Ile Glu Asp Cys 470 475 480 TGG GAC CAG GAT GCA GAG GCT CGG CTT ACT GCA CAG TGT GCT GAG GAA 1905 Trp Asp Gln Asp Ala Glu Ala Arg Leu Thr Ala Gln Cys Ala Glu Glu 485 490 495 AGG ATG GCT GAA CTT ATG ATG ATT TGG GAA AGA AAC AAA TCT GTG AGC 1953 Arg Met Ala Glu Leu Met Met Ile Trp Glu Arg Asn Lys Ser Val Ser 500 505 510 515 CCA ACA GTC AAT CCA ATG TCT ACT GCT ATG CAG AAT GAA CGC AAC CTG 2001 Pro Thr Val Asn Pro Met Ser Thr Ala Met Gln Asn Glu Arg Asn Leu 520 525 530 TCA CAT AAT AGG CGT GTG CCA AAA ATT GGT CCT TAT CCA GAT TAT TCT 2049 Ser His Asn Arg Arg Val Pro Lys Ile Gly Pro Tyr Pro Asp Tyr Ser wo 98/52U38 PCT/US98/09519 73 535 540 545 TCC TCC TCA TAC ATT GAA GAC TCT ATC CAT CAT ACT GAC AGC ATC GTG 2097 Ser Ser Ser Tyr Ile Glu Asp Ser Ile His His Thr Asp Ser Ile Val 550 555 560 AAG AAT ATT TCC TCT GAG CAT TCT ATG TCC AGC ACA CCT TTG ACT ATA 2145 Lys Asn Ile Ser Ser Glu His Ser Met Ser Ser Thr Pro Leu Thr Ile 565 570 575 GGG GAA AAA AAC CGA AAT TCA ATT AAC TAT GAA CGA CAG CAA GCA CAA 2193 Gly Glu Lys Asn Arg Asn Ser Ile Asn Tyr Glu Arg Gln Gln Ala Gln 580 585 590 595 GCT CGA ATC CCC AGC CCT GAA ACA AGT GTC ACC AGC CTC TCC ACC AAC 2241 Ala Arg Ile Pro Ser Pro Glu Thr Ser Val Thr Ser Leu Ser Thr Asn 600 605 610 ACA ACA ACC ACA AAC ACC ACA GGA CTC ACG CCA AGT ACT GGC ATG ACT 2289 Thr Thr Thr Thr Asn Thr Thr Gly Leu Thr Pro Ser Thr Gly Met Thr 615 620 625 ACT ATA TCT GAG ATG CCA TAC CCA GAT GAA ACA AAT CTG CAT ACC ACA 2337 Thr Ile Ser Glu Met Pro Tyr Pro Asp Glu Thr Asn Leu His Thr Thr 630 635 640 AAT GTT GCA CAG TCA ATT GGG CCA ACC CCT GTC TGC TTA CAG CTG ACA 2385 Asn Val Ala Gln Ser Ile Gly Pro Thr Pro Val Cys Leu Gln Leu Thr 645 650 655 GAA GAA GAC TTG GAA ACC AAC AAG CTA GAC CCA AAA GAA GTT GAT AAG 2433 Glu Glu Asp Leu Glu Thr Asn Lys Leu Asp Pro Lys Glu Val Asp Lys 660 665 670 675 AAC CTC AAG GAA AGC TCT GAT GAG AAT CTC ATG GAG CAC TCT CTT AAA 2481 Asn Leu Lys Glu Ser Ser Asp Glu Asn Leu Met Glu His Ser Leu Lys 680 685 690 CAG TTC AGT GGC CCA GAC CCA CTG AGC AGT ACT AGT TCT AGC TTG CTT 2529 Gln Phe Ser Gly Pro Asp Pro Leu Ser Ser Thr Ser Ser Ser Leu Leu 695 700 705 TAC CCA CTC ATA AAA CTT GCA GTA GAA GCA ACT GGA CAG CAG GAC TTC 2577 Tyr Pro Leu Ile Lys Leu Ala Val Glu Ala Thr Gly Gln Gln Asp Phe 710 715 720 ACA CAG ACT GCA AAT GGC CAA GCA TGT TTG ATT CCT GAT GTT CTG CCT 2625 Thr Gln Thr Ala Asn Gly Gln Ala Cys Leu Ile Pro Asp Val Leu Pro 725 730 735 ACT CAG ATC TAT CCT CTC CCC AAG CAG CAG AAC CTT CCC AAG AGA CCT 2673 Thr Gln Ile Tyr Pro Leu Pro Lys Gln Gln Asn Leu Pro Lys Arg Pro 740 745 750 755 ACT AGT TTG CCT TTG AAC ACC AAA AAT TCA ACA AAA GAG CCC CGG CTA 2721 Thr Ser Leu Pro Leu Asn Thr Lys Asn Ser Thr Lys Glu Pro Arg Leu WO 98/52U38 PCT/US98/09519 74 760 765 770 AAA TTT GGC AGC AAG CAC AAA TCA AAC TTG AAA CAA GTC GAA ACT GGA 2769 Lys Phe Gly Ser Lys His Lys Ser Asn Leu Lys Gln Val Glu Thr Gly 775 780 785 GTT GCC AAG ATG AAT ACA ATC AAT GCA GCA GAA CCT CAT GTG GTG ACA 2817 Val Ala Lys Met Asn Thr Ile Asn Ala Ala Glu Pro His Val Val Thr 790 795 800 GTC ACC ATG AAT GGT GTG GCA GGT AGA AAC CAC AGT GTT AAC TCC CAT 2865 Val Thr Met Asn Gly Val Ala Gly Arg Asn His Ser Val Asn Ser His 805 810 815 GCT GCC ACA ACC CAA TAT GCC AAT GGG ACA GTA CTA TCT GGC CAA ACA 2913 Ala Ala Thr Thr Gln Tyr Ala Asn Gly Thr Val Leu Ser Gly Gln Thr 820 825 830 835 ACC AAC ATA GTG ACA CAT AGG GCC CAA GAA ATG TTG CAG AAT CAG TTT 2961 Thr Asn Ile Val Thr His Arg Ala Gln Glu Met Leu Gln Asn Gln Phe 840 845 850 ATT GGT GAG GAC ACC CGG CTG AAT ATT AAT TCC AGT CCT GAT GAG CAT 3009 Ile Gly Glu Asp Thr Arg Leu Asn Ile Asn Ser Ser Pro Asp Glu His 855 860 865 GAG CCT TTA CTG AGA CGA GAG CAA CAA GCT GGC CAT GAT GAA GGT GTT 3057 Glu Pro Leu Leu Arg Arg Glu Gln Gln Ala Gly His Asp Glu Gly Val 870 875 880 CTG GAT CGT CTT GTG GAC AGG AGG GAA CGG CCA CTA GAA GGT GGC CGA 3105 Leu Asp Arg Leu Val Asp Arg Arg Glu Arg Pro Leu Glu Gly Gly Arg 885 890 895 ACT AAT TCC AAT AAC AAC AAC AGC AAT CCA TGT TCA GAA CAA GAT GTT 3153 Thr Asn Ser Asn Asn Asn Asn Ser Asn Pro Cys Ser Glu Gln Asp Val 900 905 910 915 CTT GCA CAG GGT GTT CCA AGC ACA GCA GCA GAT CCT GGG CCA TCA AAG 3201 Leu Ala Gln Gly Val Pro Ser Thr Ala Ala Asp Pro Gly Pro Ser Lys 920 925 930 CCC AGA AGA GCA CAG AGG CCT AAT TCT CTG GAT CTT TCA GCC ACA AAT 3249 Pro Arg Arg Ala Gln Arg Pro Asn Ser Leu Asp Leu Ser Ala Thr Asn 935 940 945 GTC CTG GAT GGC AGC AGT ATA CAG ATA GGT GAG TCA ACA CAA GAT GGC 3297 Val Leu Asp Gly Ser Ser Ile Gln Ile Gly Glu Ser Thr Gln Asp Gly 950 955 960 AAA TCA GGA TCA GGT GAA AAG ATC AAG AAA CGT GTG AAA ACT CCC TAT 3345 Lys Ser Gly Ser Gly Glu Lys Ile Lys Lys Arg Val Lys Thr Pro Tyr 965 970 975 TCT CTT AAG CGG TGG CGC CCC TCC ACC TGG GTC ATC TCC ACT GAA TCG 3393 Ser Leu Lys Arg Trp Arg Pro Ser Thr Trp Val Ile Ser Thr Glu Ser wo 98/zUj5 PCT/US98/09519 75 980 985 990 995 CTG GAC TGT GAA GTC AAC AAT AAT GGC AGT AAC AGG GCA GTT CAT TCC 3441 Leu Asp Cys Glu Val Asn Asn Asn Gly Ser Asn Arg Ala Val His Ser 1000 1005 1010 AAA TCC AGC ACT GCT GTT TAC CTT GCA GAA GGA GGC ACT GCT ACA ACC 3489 Lys Ser Ser Thr Ala Val Tyr Leu Ala Glu Gly Gly Thr Ala Thr Thr 1015 1020 1025 ATG GTG TCT AAA GAT ATA GGA ATG AAC TGT CTG TGAAATGTTT TCAAGCCTAT 3542 Met Val Ser Lys Asp Ile Gly Met Asn Cys Leu 1030 1035 GGAGTGAAAT TATTTTTTGC ATCATTTAAA CATGCAGAAG ATGTTTAAAA AAAAAAAAA 3601 (2) INFORMATION FOR SEQ ID NO:10: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 1038 amino acids (B) TYPE: amino acid (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (xi) SEQUENCE DESCRIPTION: SEQ ID NO:10: Met Thr Ser Ser Leu Gln Arg Pro Trp Arg Val Pro Trp Leu Pro Trp 1 5 10 15 Thr Ile Leu Leu Val Ser Thr Ala Ala Ala Ser Gln Asn Gln Glu Arg 20 25 30 Leu Cys Ala Phe Lys Asp Pro Tyr Gln Gln Asp Leu Gly Ile Gly Glu 35 40 45 Ser Arg Ile Ser His Glu Asn Gly Thr Ile Leu Cys Ser Lys Gly Ser 50 55 60 Thr Cys Tyr Gly Leu Trp Glu Lys Ser Lys Gly Asp Ile Asn Leu Val 65 70 75 80 Lys Gln Gly Cys Trp Ser His Ile Gly Asp Pro Gln Glu Cys His Tyr 85 90 95 Glu Glu Cys Val Val Thr Thr Thr Pro Pro Ser Ile Gln Asn Gly Thr 100 105 110 Tyr Arg Phe Cys Cys Cys Ser Thr Asp Leu Cys Asn Val Asn Phe Thr 115 120 125 Glu Asn Phe Pro Pro Pro Asp Thr Thr Pro Leu Ser Pro Pro His Ser 130 135 140 Phe Asn Arg Asp Glu Thr Ile Ile Ile Ala Leu Ala Ser Val Ser Val WO 98/52038 PCT/US98/09519 76 145 150 155 160 Leu Ala Val Leu Ile Val Ala Leu Cys Phe Gly Tyr Arg Met Leu Thr 165 170 175 Gly Asp Arg Lys Gln Gly Leu His Ser Met Asn Met Met Glu Ala Ala 180 185 190 Ala Ser Glu Pro Ser Leu Asp Leu Asp Asn Leu Lys Leu Leu Glu Leu 195 200 205 Ile Gly Arg Gly Arg Tyr Gly Ala Val Tyr Lys Gly Ser Leu Asp Glu 210 215 220 Arg Pro Val Ala Val Lys Val Phe Ser Phe Ala Asn Arg Gln Asn Phe 225 230 235 240 Ile Asn Glu Lys Asn Ile Tyr Arg Val Pro Leu Met Glu His Asp Asn 245 250 255 Ile Ala Arg Phe Ile Val Gly Asp Glu Arg Val Thr Ala Asp Gly Arg 260 265 270 Met Glu Tyr Leu Leu Val Met Glu Tyr Tyr Pro Asn Gly Ser Leu Cys 275 280 285 Lys Tyr Leu Ser Leu His Thr Ser Asp Trp Val Ser Ser Cys Arg Leu 290 295 300 Ala His Ser Val Thr Arg Gly Leu Ala Tyr Leu His Thr Glu Leu Pro 305 310 315 320 Arg Gly Asp His Tyr Lys Pro Ala Ile Ser His Arg Asp Leu Asn Ser 325 330 335 Arg Asn Val Leu Val Lys Asn Asp Gly Thr Cys Val Ile Ser Asp Phe 340 345 350 Gly Leu Ser Met Arg Leu Thr Gly Asn Arg Leu Val Arg Pro Gly Glu 355 360 365 Glu Asp Asn Ala Ala Ile Ser Glu Val Gly Thr Ile Arg Tyr Met Ala 370 375 380 Pro Glu Val Leu Glu Gly Ala Val Asn Leu Arg Asp Cys Glu Ser Ala 385 390 395 400 Leu Lys Gln Val Asp Met Tyr Ala Leu Gly Leu Ile Tyr Trp Glu Ile 405 410 415 Phe Met Arg Cys Thr Asp Leu Phe Pro Gly Glu Ser Val Pro Glu Tyr 420 425 430 Gln Met Ala Phe Gln Thr Glu Val Gly Asn His Pro Thr Phe Glu Asp 435 440 445 WO 98/52038 PCT/US98/09519 77 Met Gln Val Leu Val Ser Arg Glu Lys Gln Arg Pro Lys Phe Pro Glu 450 455 460 Ala Trp Lys Glu Asn Ser Leu Ala Val Arg Ser Leu Lys Glu Thr Ile 465 470 475 480 Glu Asp Cys Trp Asp Gln Asp Ala Glu Ala Arg Leu Thr Ala Gln Cys 485 490 495 Ala Glu Glu Arg Met Ala Glu Leu Met Met Ile Trp Glu Arg Asn Lys 500 505 510 Ser Val Ser Pro Thr Val Asn Pro Met Ser Thr Ala Met Gln Asn Glu 515 520 525 Arg Asn Leu Ser His Asn Arg Arg Val Pro Lys Ile Gly Pro Tyr Pro 530 535 540 Asp Tyr Ser Ser Ser Ser Tyr Ile Glu Asp Ser Ile His His Thr Asp 545 550 555 560 Ser Ile Val Lys Asn Ile Ser Ser Glu His Ser Met Ser Ser Thr Pro 565 570 575 Leu Thr Ile Gly Glu Lys Asn Arg Asn Ser Ile Asn Tyr Glu Arg Gln 580 585 590 Gln Ala Gln Ala Arg Ile Pro Ser Pro Glu Thr Ser Val Thr Ser Leu 595 600 605 Ser Thr Asn Thr Thr Thr Thr Asn Thr Thr Gly Leu Thr Pro Ser Thr 610 615 620 Gly Met Thr Thr Ile Ser Glu Met Pro Tyr Pro Asp Glu Thr Asn Leu 625 630 635 640 His Thr Thr Asn Val Ala Gln Ser Ile Gly Pro Thr Pro Val Cys Leu 645 650 655 Gln Leu Thr Glu Glu Asp Leu Glu Thr Asn Lys Leu Asp Pro Lys Glu 660 665 670 Val Asp Lys Asn Leu Lys Glu Ser Ser Asp Glu Asn Leu Met Glu His 675 680 685 Ser Leu Lys Gln Phe Ser Gly Pro Asp Pro Leu Ser Ser Thr Ser Ser 690 695 700 Ser Leu Leu Tyr Pro Leu Ile Lys Leu Ala Val Glu Ala Thr Gly Gln 705 710 715 720 Gln Asp Phe Thr Gln Thr Ala Asn Gly Gln Ala Cys Leu Ile Pro Asp 725 730 735 Val Leu Pro Thr Gln Ile Tyr Pro Leu Pro Lys Gln Gln Asn Leu Pro 740 745 750 wu IaanUj PCT/US98/09519 78 Lys Arg Pro Thr Ser Leu Pro Leu Asn Thr Lys Asn Ser Thr Lys Glu 755 760 765 Pro Arg Leu Lys Phe Gly Ser Lys His Lys Ser Asn Leu Lys Gln Val 770 775 780 Glu Thr Gly Val Ala Lys Met Asn Thr Ile Asn Ala Ala Glu Pro His 785 790 795 800 Val Val Thr Val Thr Met Asn Gly Val Ala Gly Arg Asn His Ser Val 805 810 815 Asn Ser His Ala Ala Thr Thr Gln Tyr Ala Asn Gly Thr Val Leu Ser 820 825 830 Gly Gln Thr Thr Asn Ile Val Thr His Arg Ala Gln Glu Met Leu Gln 835 840 845 Asn Gln Phe Ile Gly Glu Asp Thr Arg Leu Asn Ile Asn Ser Ser Pro 850 855 860 Asp Glu His Glu Pro Leu Leu Arg Arg Glu Gln Gln Ala Gly His Asp 865 870 875 880 Glu Gly Val Leu Asp Arg Leu Val Asp Arg Arg Glu Arg Pro Leu Glu 885 890 895 Gly Gly Arg Thr Asn Ser Asn Asn Asn Asn Ser Asn Pro Cys Ser Glu 900 905 910 Gln Asp Val Leu Ala Gln Gly Val Pro Ser Thr Ala Ala Asp Pro Gly 915 920 925 Pro Ser Lys Pro Arg Arg Ala Gln Arg Pro Asn Ser Leu Asp Leu Ser 930 935 940 Ala Thr Asn Val Leu Asp Gly Ser Ser Ile Gln Ile Gly Glu Ser Thr 945 950 955 960 Gln Asp Gly Lys Ser Gly Ser Gly Glu Lys Ile Lys Lys Arg Val Lys 965 970 975 Thr Pro Tyr Ser Leu Lys Arg Trp Arg Pro Ser Thr Trp Val Ile Ser 980 985 990 Thr Glu Ser Leu Asp Cys Glu Val Asn Asn Asn Gly Ser Asn Arg Ala 995 1000 1005 Val His Ser Lys Ser Ser Thr Ala Val Tyr Leu Ala Glu Gly Gly Thr 1010 1015 1020 Ala Thr Thr Met Val Ser Lys Asp Ile Gly Met Asn Cys Leu 1025 1030 1035 wo bin.uan.3 PCT/US98/09519 79 (2) INFORMATION FOR SEQ ID NO:11: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 3508 base pairs (B) TYPE: nucleic acid (C) STRANDEDNESS: double (D) TOPOLOGY: linear (ii) MOLECULE TYPE: cDNA (ix) FEATURE: (A) NAME/KEY: CDS (B) LOCATION: join(17..3130) (xi) SEQUENCE DESCRIPTION: SEQ ID NO:11: CTTTGCTGGC CCAGGG ATG ACT TCC TCG CTG CAT CGG CCC TTT CGG GTG 49 Met Thr Ser Ser Leu His Arg Pro Phe Arg Val 1 5 10 CCC TGG CTG CTA TGG GCC GTC CTG CTG GTC AGC ACT ACG GCT GCT TCT 97 Pro Trp Leu Leu Trp Ala Val Leu Leu Val Ser Thr Thr Ala Ala Ser 15 20 25 CAG AAT CAA GAA CGG CTG TGT GCA TTT AAA GAT CCA TAT CAA CAA GAT 145 Gln Asn Gln Glu Arg Leu Cys Ala Phe Lys Asp Pro Tyr Gln Gln Asp 30 35 40 CTT GGG ATA GGT GAG AGT CGA ATC TCT CAT GAA AAT GGG ACA ATA TTA 193 Leu Gly Ile Gly Glu Ser Arg Ile Ser His Glu Asn Gly Thr Ile Leu 45 50 55 TGT TCC AAA GGG AGC ACG TGT TAT GGT CTG TGG GAG AAA TCA AAA GGG 241 Cys Ser Lys Gly Ser Thr Cys Tyr Gly Leu Trp Glu Lys Ser Lys Gly 60 65 70 75 GAC ATC AAT CTT GTG AAA CAA GGA TGT TGG TCT CAC ATC GGT GAT CCC 289 Asp Ile Asn Leu Val Lys Gln Gly Cys Trp Ser His Ile Gly Asp Pro 80 85 90 CAA GAG TGC CAC TAT GAA GAG TGT GTA GTA ACT ACC ACC CCA CCC TCA 337 Gln Glu Cys His Tyr Glu Glu Cys Val Val Thr Thr Thr Pro Pro Ser 95 100 105 ATT CAG AAT GGA ACG TAC CGC TTT TGC TGC TGT AGT ACA GAT TTA TGT 385 Ile Gln Asn Gly Thr Tyr Arg Phe Cys Cys Cys Ser Thr Asp Leu Cys 110 115 120 AAT GTC AAC TTT ACT GAG AAC TTT CCA CCC CCT GAC ACA ACA CCA CTC 433 Asn Val Asn Phe Thr Glu Asn Phe Pro Pro Pro Asp Thr Thr Pro Leu 125 130 135 AGT CCA CCT CAT TCA TTT AAT CGA GAT GAA ACG ATA ATC ATT GCT TTG 481 Ser Pro Pro His Ser Phe Asn Arg Asp Glu Thr Ile Ile Ile Ala Leu WU 95/?SZU5 PCT/US98/09519 80 140 145 150 155 GCA TCA GTT TCT GTG TTA GCT GTT TTG ATA GTC GCC TTA TGT TTT GGA 529 Ala Ser Val Ser Val Leu Ala Val Leu Ile Val Ala Leu Cys Phe Gly 160 165 170 TAC AGA ATG TTG ACA GGA GAC CGG AAA CAG GGT CTT CAC AGC ATG AAC 577 Tyr Arg Met Leu Thr Gly Asp Arg Lys Gln Gly Leu His Ser Met Asn 175 180 185 ATG ATG GAG GCG GCA GCA GCA GAG CCC TCC CTT GAC CTG GAT AAC CTG 625 Met Met Glu Ala Ala Ala Ala Glu Pro Ser Leu Asp Leu Asp Asn Leu 190 195 200 AAG CTG CTG GAG CTG ATT GGA CGG GGT CGA TAC GGA GCA GTA TAT AAA 673 Lys Leu Leu Glu Leu Ile Gly Arg Gly Arg Tyr Gly Ala Val Tyr Lys 205 210 215 GGT TCC TTG GAT GAG CGT CCA GTT GCT GTA AAA GTA TTT TCT TTT GCA 721 Gly Ser Leu Asp Glu Arg Pro Val Ala Val Lys Val Phe Ser Phe Ala 220 225 230 235 AAC CGT CAG AAT TTT ATA AAT GAA AAA AAC ATT TAC AGA GTG CCT TTG 769 Asn Arg Gln Asn Phe Ile Asn Glu Lys Asn Ile Tyr Arg Val Pro Leu 240 245 250 ATG GAA CAT GAC AAC ATT GCT CGC TTC ATA GTT GGA GAC GAG AGG CTC 817 Met Glu His Asp Asn Ile Ala Arg Phe Ile Val Gly Asp Glu Arg Leu 255 260 265 ACT GCA GAC GGC CGC ATG GAG TAT TTG CTT GTG ATG GAG TAT TAT CCC 865 Thr Ala Asp Gly Arg Met Glu Tyr Leu Leu Val Met Glu Tyr Tyr Pro 270 275 280 AAT GGA TCT CTG TGC AAA TAT CTG AGT CTC CAC ACA AGT GAT TGG GTA 913 Asn Gly Ser Leu Cys Lys Tyr Leu Ser Leu His Thr Ser Asp Trp Val 285 290 295 AGC TCT TGC CGT CTG GCT CAT TCT GTG ACT AGA GGA CTG GCT TAT CTT 961 Ser Ser Cys Arg Leu Ala His Ser Val Thr Arg Gly Leu Ala Tyr Leu 300 305 310 315 CAC ACA GAA TTA CCA CGA GGA GAT CAT TAT AAA CCC GCA ATC TCC CAC 1009 His Thr Glu Leu Pro Arg Gly Asp His Tyr Lys Pro Ala Ile Ser His 320 325 330 CGA GAT TTA AAC AGC AGG AAT GTC CTG GTA AAG AAT GAC GGC GCG TGT 1057 Arg Asp Leu Asn Ser Arg Asn Val Leu Val Lys Asn Asp Gly Ala Cys 335 340 345 GTT ATC AGT GAC TTT GGT TTA TCC ATG AGG CTA ACT GGA AAT CGG CTG 1105 Val Ile Ser Asp Phe Gly Leu Ser Met Arg Leu Thr Gly Asn Arg Leu 350 355 360 GTG CGC CCA GGG GAA GAA GAT AAT GCG GCT ATA AGT GAG GTT GGC ACA 1153 Val Arg Pro Gly Glu Glu Asp Asn Ala Ala Ile Ser Glu Val Gly Thr wo 98/52Uj PCT/US98/09519 81 365 370 375 ATT CGC TAT ATG GCA CCA GAA GTG CTA GAA GGA GCT GTG AAC CTG AGG 1201 Ile Arg Tyr Met Ala Pro Glu Val Leu Glu Gly Ala Val Asn Leu Arg 380 385 390 395 GAC TGT GAG TCA GCT CTG AAG CAA GTG GAC ATG TAT GCG CTT GGA CTC 1249 Asp Cys Glu Ser Ala Leu Lys Gln Val Asp Met Tyr Ala Leu Gly Leu 400 405 410 ATC TAC TGG GAG GTG TTT ATG AGG TGT ACA GAC CTC TTC CCA GGT GAA 1297 Ile Tyr Trp Glu Val Phe Met Arg Cys Thr Asp Leu Phe Pro Gly Glu 415 420 425 TCT GTA CCA GAT TAC CAG ATG GCT TTT CAG ACA GAA GTT GGA AAC CAT 1345 Ser Val Pro Asp Tyr Gln Met Ala Phe Gln Thr Glu Val Gly Asn His 430 435 440 CCC ACA TTT GAG GAT ATG CAG GTT CTT GTG TCC AGA GAG AAG CAG AGA 1393 Pro Thr Phe Glu Asp Met Gln Val Leu Val Ser Arg Glu Lys Gln Arg 445 450 455 CCC AAG TTC CCA GAA GCC TGG AAA GAA AAT AGC CTG GCA GTG AGG TCA 1441 Pro Lys Phe Pro Glu Ala Trp Lys Glu Asn Ser Leu Ala Val Arg Ser 460 465 470 475 CTC AAG GAA ACA ATT GAA GAC TGC TGG GAC CAG GAT GCA GAG GCT CGG 1489 Leu Lys Glu Thr Ile Glu Asp Cys Trp Asp Gln Asp Ala Glu Ala Arg 480 485 490 CTC ACT GCA CAG TGT GCT GAG GAG AGG ATG GCT GAA CTC ATG ATG ATA 1537 Leu Thr Ala Gln Cys Ala Glu Glu Arg Met Ala Glu Leu Met Met Ile 495 500 505 TGG GAG AGA AAC AAG TCT GTG AGC CCA ACG GTC AAC CCA ATG TCA ACT 1585 Trp Glu Arg Asn Lys Ser Val Ser Pro Thr Val Asn Pro Met Ser Thr 510 515 520 GCT ATG CAG AAT GAA CGC AAC CTG TCA CAT AAT AGG CGT GTG CCA AAA 1633 Ala Met Gln Asn Glu Arg Asn Leu Ser His Asn Arg Arg Val Pro Lys 525 530 535 ATC GGG CCT TAC CCA GAT TAT TCC TCT TCC TCA TAT ATT GAA GAC TCT 1681 Ile Gly Pro Tyr Pro Asp Tyr Ser Ser Ser Ser Tyr Ile Glu Asp Ser 540 545 550 555 ATC CAT CAT ACT GAC AGC ATT GTG AAG AAT ATT TCC TCT GAG CAT TCG 1729 Ile His His Thr Asp Ser Ile Val Lys Asn Ile Ser Ser Glu His Ser 560 565 570 ATG TCC AGC ACA CCA TTG ACA ATA GGA GAA AAG AAT CGA AAT TCA ATT 1777 Met Ser Ser Thr Pro Leu Thr Ile Gly Glu Lys Asn Arg Asn Ser Ile 575 580 585 AAT TAT GAA CGA CAG CAA GCA CAA GCT CGA ATC CCT AGC CCA GAA ACA 1825 Asn Tyr Glu Arg Gln Gln Ala Gln Ala Arg Ile Pro Ser Pro Glu Thr WO 98/52UJ8 PCT/US98/09519 82 590 595 600 AGC GTC ACA AGC CTG TCC ACA AAC ACA ACC ACC ACA AAC ACC ACC GGC 1873 Ser Val Thr Ser Leu Ser Thr Asn Thr Thr Thr Thr Asn Thr Thr Gly 605 610 615 CTC ACT CCA AGT ACT GGC ATG ACC ACT ATA TCT GAG ATG CCA TAC CCA 1921 Leu Thr Pro Ser Thr Gly Met Thr Thr Ile Ser Glu Met Pro Tyr Pro 620 625 630 635 GAT GAG ACA CAT TTG CAC GCC ACA AAT GTT GCA CAG TCA ATC GGG CCA 1969 Asp Glu Thr His Leu His Ala Thr Asn Val Ala Gln Ser Ile Gly Pro 640 645 650 ACC CCT GTC TGC TTA CAG CTG ACA GAA GAA GAC TTG GAG ACT AAT AAG 2017 Thr Pro Val Cys Leu Gln Leu Thr Glu Glu Asp Leu Glu Thr Asn Lys 655 660 665 CTA GAT CCA AAA GAA GTT GAT AAG AAC CTC AAG GAA AGC TCT GAT GAG 2065 Leu Asp Pro Lys Glu Val Asp Lys Asn Leu Lys Glu Ser Ser Asp Glu 670 675 680 AAT CTC ATG GAG CAT TCT CTG AAG CAG TTC AGT GGG CCA GAC CCA TTG 2113 Asn Leu Met Glu His Ser Leu Lys Gln Phe Ser Gly Pro Asp Pro Leu 685 690 695 AGC AGT ACC AGT TCT AGC TTG CTT TAT CCA CTC ATA AAG CTC GCA GTG 2161 Ser Ser Thr Ser Ser Ser Leu Leu Tyr Pro Leu Ile Lys Leu Ala Val 700 705 710 715 GAA GTG ACT GGA CAA CAG GAC TTC ACA CAG GCT GCA AAT GGG CAA GCA 2209 Glu Val Thr Gly Gln Gln Asp Phe Thr Gln Ala Ala Asn Gly Gln Ala 720 725 730 TGT TTA ATT CCT GAT GTT CCA CCT GCT CAG ATC TAT CCT CTC CCT AAG 2257 Cys Leu Ile Pro Asp Val Pro Pro Ala Gln Ile Tyr Pro Leu Pro Lys 735 740 745 CAA CAG AAC CTT CCT AAG AGA CCT ACT AGT TTG CCT TTG AAC ACC AAA 2305 Gln Gln Asn Leu Pro Lys Arg Pro Thr Ser Leu Pro Leu Asn Thr Lys 750 755 760 AAT TCA ACA AAA GAA CCC CGG CTA AAA TTT GGC AAC AAG CAC AAA TCA 2353 Asn Ser Thr Lys Glu Pro Arg Leu Lys Phe Gly Asn Lys His Lys Ser 765 770 775 AAC TTG AAA CAA GTA GAA ACT GGA GTT GCC AAG ATG AAT ACA ATC AAT 2401 Asn Leu Lys Gln Val Glu Thr Gly Val Ala Lys Met Asn Thr Ile Asn 780 785 790 795 GCA GCA GAG CCT CAT GTG GTG ACA GTA ACT ATG AAT GGT GTG GCA GGT 2449 Ala Ala Glu Pro His Val Val Thr Val Thr Met Asn Gly Val Ala Gly 800 805 810 AGA AGC CAC AAT GTT AAT TCT CAT GCT GCC ACA ACC CAG TAT GCC AAT 2497 Arg Ser His Asn Val Asn Ser His Ala Ala Thr Thr Gln Tyr Ala Asn WO 98/52038 PCT/US98/09519 83 815 820 825 GGC GCA GTG CCA GCT GGC CAG GCA GCC AAC ATA GTG GCA CAT AGG TCC 2545 Gly Ala Val Pro Ala Gly Gln Ala Ala Asn Ile Val Ala His Arg Ser 830 835 840 CAA GAA ATG CTG CAG AAT CAA TTT ATT GGT GAG GAT ACC AGG CTG AAT 2593 Gln Glu Met Leu Gln Asn Gln Phe Ile Gly Glu Asp Thr Arg Leu Asn 845 850 855 ATC AAT TCC AGT CCT GAT GAG CAT GAA CCT TTA CTG AGA CGA GAG CAA 2641 Ile Asn Ser Ser Pro Asp Glu His Glu Pro Leu Leu Arg Arg Glu Gln 860 865 870 875 CAG GCT GGC CAT GAT GAA GGG GTT CTG GAT CGT TTG GTA GAT AGG AGG 2689 Gln Ala Gly His Asp Glu Gly Val Leu Asp Arg Leu Val Asp Arg Arg 880 885 890 GAA CGG CCA TTA GAA GGT GGC CGA ACA AAT TCC AAT AAC AAC AAC AGC 2737 Glu Arg Pro Leu Glu Gly Gly Arg Thr Asn Ser Asn Asn Asn Asn Ser 895 900 905 AAT CCA TGT TCA GAA CAA GAT ATC CTT ACA CAA GGT GTT ACA AGC ACA 2785 Asn Pro Cys Ser Glu Gln Asp Ile Leu Thr Gln Gly Val Thr Ser Thr 910 915 920 GCT GCA GAT CCT GGG CCA TCA AAG CCC AGA AGA GCA CAG AGG CCC AAT 2833 Ala Ala Asp Pro Gly Pro Ser Lys Pro Arg Arg Ala Gln Arg Pro Asn 925 930 935 TCT CTG GAT CTT TCA GCC ACA AAT ATC CTG GAT GGC AGC AGT ATA CAG 2881 Ser Leu Asp Leu Ser Ala Thr Asn Ile Leu Asp Gly Ser Ser Ile Gln 940 945 950 955 ATA GGT GAG TCA ACA CAA GAT GGC AAA TCA GGA TCA GGT GAA AAG ATC 2929 Ile Gly Glu Ser Thr Gln Asp Gly Lys Ser Gly Ser Gly Glu Lys Ile 960 965 970 AAG AGA CGT GTG AAA ACT CCA TAC TCT CTT AAG CGG TGG CGC CCG TCC 2977 Lys Arg Arg Val Lys Thr Pro Tyr Ser Leu Lys Arg Trp Arg Pro Ser 975 980 985 ACC TGG GTC ATC TCC ACC GAG CCG CTG GAC TGT GAG GTC AAC AAC AAT 3025 Thr Trp Val Ile Ser Thr Glu Pro Leu Asp Cys Glu Val Asn Asn Asn 990 995 1000 GGC AGT GAC AGG GCA GTC CAT TCT AAA TCT AGC ACT GCT GTG TAC CTT 3073 Gly Ser Asp Arg Ala Val His Ser Lys Ser Ser Thr Ala Val Tyr Leu 1005 1010 1015 GCA GAG GGA GGC ACT GCC ACG ACC ACA GTG TCT AAA GAT ATA GGA ATG 3121 Ala Glu Gly Gly Thr Ala Thr Thr Thr Val Ser Lys Asp Ile Gly Met 1020 1025 1030 1035 AAT TGT CTG TGAGATGTTT TCAAGCTTAT GGAGTGAAAT TATTTTTTTG 3170 Asn Cys Leu wu 9Wa/Aoa PCT/US98/09519 84 CATCATTTAA ACATGCAGAA GACATTTAAA AAAAAAACTG CTTTAACCTC CTGTCAGCAC 3230 CCCTTCCCAC CCCTGCAGCA AGGACTTGCT TTAAATAGAT TTCAGCTATG CAGAAAATTT 3290 TAGCTTATGC TTCCATAATT TTTAATTTTG TTTTTTAAGT TTTGCACTTT TGTTTAGTCT 3350 TGCTAAAGTT ATATTTGTCT GTTATGACCA CATTATATGT GTGCTTATCC AAAGTGGTCT 3410 CCAAATATTT TTTTAAGAAA AAAGCCCAAA CAATGGATTG CTGATAATCA GTTTGGACCA 3470 TTTTCTAAAG GTCATTAAAA CAGAAGCAAA TTCAGACC 3508 (2) INFORMATION FOR SEQ ID NO:12: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 1038 amino acids (B) TYPE: amino acid (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (xi) SEQUENCE DESCRIPTION: SEQ ID NO:12: Met Thr Ser Ser Leu His Arg Pro Phe Arg Val Pro Trp Leu Leu Trp 1 5 10 15 Ala Val Leu Leu Val Ser Thr Thr Ala Ala Ser Gln Asn Gln Glu Arg 20 25 30 Leu Cys Ala Phe Lys Asp Pro Tyr Gln Gln Asp Leu Gly Ile Gly Glu 35 40 45 Ser Arg Ile Ser His Glu Asn Gly Thr Ile Leu Cys Ser Lys Gly Ser 50 55 60 Thr Cys Tyr Gly Leu Trp Glu Lys Ser Lys Gly Asp Ile Asn Leu Val 65 70 75 80 Lys Gln Gly Cys Trp Ser His Ile Gly Asp Pro Gln Glu Cys His Tyr 85 90 95 Glu Glu Cys Val Val Thr Thr Thr Pro Pro Ser Ile Gln Asn Gly Thr 100 105 110 Tyr Arg Phe Cys Cys Cys Ser Thr Asp Leu Cys Asn Val Asn Phe Thr 115 120 125 Glu Asn Phe Pro Pro Pro Asp Thr Thr Pro Leu Ser Pro Pro His Ser 130 135 140 Phe Asn Arg Asp Glu Thr Ile Ile Ile Ala Leu Ala Ser Val Ser Val 145 150 155 160 WO 98/52U38 PCT/US98/09519 85 Leu Ala Val Leu Ile Val Ala Leu Cys Phe Gly Tyr Arg Met Leu Thr 165 170 175 Gly Asp Arg Lys Gln Gly Leu His Ser Met Asn Met Met Glu Ala Ala 180 185 190 Ala Ala Glu Pro Ser Leu Asp Leu Asp Asn Leu Lys Leu Leu Glu Leu 195 200 205 Ile Gly Arg Gly Arg Tyr Gly Ala Val Tyr Lys Gly Ser Leu Asp Glu 210 215 220 Arg Pro Val Ala Val Lys Val Phe Ser Phe Ala Asn Arg Gln Asn Phe 225 230 235 240 Ile Asn Glu Lys Asn Ile Tyr Arg Val Pro Leu Met Glu His Asp Asn 245 250 255 Ile Ala Arg Phe Ile Val Gly Asp Glu Arg Leu Thr Ala Asp Gly Arg 260 265 270 Met Glu Tyr Leu Leu Val Met Glu Tyr Tyr Pro Asn Gly Ser Leu Cys 275 280 285 Lys Tyr Leu Ser Leu His Thr Ser Asp Trp Val Ser Ser Cys Arg Leu 290 295 300 Ala His Ser Val Thr Arg Gly Leu Ala Tyr Leu His Thr Glu Leu Pro 305 310 315 320 Arg Gly Asp His Tyr Lys Pro Ala Ile Ser His Arg Asp Leu Asn Ser 325 330 335 Arg Asn Val Leu Val Lys Asn Asp Gly Ala Cys Val Ile Ser Asp Phe 340 345 350 Gly Leu Ser Met Arg Leu Thr Gly Asn Arg Leu Val Arg Pro Gly Glu 355 360 365 Glu Asp Asn Ala Ala Ile Ser Glu Val Gly Thr Ile Arg Tyr Met Ala 370 375 380 Pro Glu Val Leu Glu Gly Ala Val Asn Leu Arg Asp Cys Glu Ser Ala 385 390 395 400 Leu Lys Gln Val Asp Met Tyr Ala Leu Gly Leu Ile Tyr Trp Glu Val 405 410 415 Phe Met Arg Cys Thr Asp Leu Phe Pro Gly Glu Ser Val Pro Asp Tyr 420 425 430 Gln Met Ala Phe Gln Thr Glu Val Gly Asn His Pro Thr Phe Glu Asp 435 440 445 Met Gln Val Leu Val Ser Arg Glu Lys Gln Arg Pro Lys Phe Pro Glu 450 455 460 WO 98/52038 PCT/US98/09519 86 Ala Trp Lys Glu Asn Ser Leu Ala Val Arg Ser Leu Lys Glu Thr Ile 465 470 475 480 Glu Asp Cys Trp Asp Gln Asp Ala Glu Ala Arg Leu Thr Ala Gln Cys 485 490 495 Ala Glu Glu Arg Met Ala Glu Leu Met Met Ile Trp Glu Arg Asn Lys 500 505 510 Ser Val Ser Pro Thr Val Asn Pro Met Ser Thr Ala Met Gln Asn Glu 515 520 525 Arg Asn Leu Ser His Asn Arg Arg Val Pro Lys Ile Gly Pro Tyr Pro 530 535 540 Asp Tyr Ser Ser Ser Ser Tyr Ile Glu Asp Ser Ile His His Thr Asp 545 550 555 560 Ser Ile Val Lys Asn Ile Ser Ser Glu His Ser Met Ser Ser Thr Pro 565 570 575 Leu Thr Ile Gly Glu Lys Asn Arg Asn Ser Ile Asn Tyr Glu Arg Gln 580 585 590 Gln Ala Gln Ala Arg Ile Pro Ser Pro Glu Thr Ser Val Thr Ser Leu 595 600 605 Ser Thr Asn Thr Thr Thr Thr Asn Thr Thr Gly Leu Thr Pro Ser Thr 610 615 620 Gly Met Thr Thr Ile Ser Glu Met Pro Tyr Pro Asp Glu Thr His Leu 625 630 635 640 His Ala Thr Asn Val Ala Gln Ser Ile Gly Pro Thr Pro Val Cys Leu 645 650 655 Gln Leu Thr Glu Glu Asp Leu Glu Thr Asn Lys Leu Asp Pro Lys Glu 660 665 670 Val Asp Lys Asn Leu Lys Glu Ser Ser Asp Glu Asn Leu Met Glu His 675 680 685 Ser Leu Lys Gln Phe Ser Gly Pro Asp Pro Leu Ser Ser Thr Ser Ser 690 695 700 Ser Leu Leu Tyr Pro Leu Ile Lys Leu Ala Val Glu Val Thr Gly Gln 705 710 715 720 Gln Asp Phe Thr Gln Ala Ala Asn Gly Gln Ala Cys Leu Ile Pro Asp 725 730 735 Val Pro Pro Ala Gln Ile Tyr Pro Leu Pro Lys Gln Gln Asn Leu Pro 740 745 750 Lys Arg Pro Thr Ser Leu Pro Leu Asn Thr Lys Asn Ser Thr Lys Glu WO 98/52U038S PCT/US98/09519 87 755 760 765 Pro Arg Leu Lys Phe Gly Asn Lys His Lys Ser Asn Leu Lys Gln Val 770 775 780 Glu Thr Gly Val Ala Lys Met Asn Thr Ile Asn Ala Ala Glu Pro His 785 790 795 800 Val Val Thr Val Thr Met Asn Gly Val Ala Gly Arg Ser His Asn Val 805 810 815 Asn Ser His Ala Ala Thr Thr Gln Tyr Ala Asn Gly Ala Val Pro Ala 820 825 830 Gly Gln Ala Ala Asn Ile Val Ala His Arg Ser Gln Glu Met Leu Gln 835 840 845 Asn Gln Phe Ile Gly Glu Asp Thr Arg Leu Asn Ile Asn Ser Ser Pro 850 855 860 Asp Glu His Glu Pro Leu Leu Arg Arg Glu Gln Gln Ala Gly His Asp 865 870 875 880 Glu Gly Val Leu Asp Arg Leu Val Asp Arg Arg Glu Arg Pro Leu Glu 885 890 895 Gly Gly Arg Thr Asn Ser Asn Asn Asn Asn Ser Asn Pro Cys Ser Glu 900 905 910 Gln Asp Ile Leu Thr Gln Gly Val Thr Ser Thr Ala Ala Asp Pro Gly 915 920 925 Pro Ser Lys Pro Arg Arg Ala Gln Arg Pro Asn Ser Leu Asp Leu Ser 930 935 940 Ala Thr Asn Ile Leu Asp Gly Ser Ser Ile Gln Ile Gly Glu Ser Thr 945 950 955 960 Gln Asp Gly Lys Ser Gly Ser Gly Glu Lys Ile Lys Arg Arg Val Lys 965 970 975 Thr Pro Tyr Ser Leu Lys Arg Trp Arg Pro Ser Thr Trp Val Ile Ser 980 985 990 Thr Glu Pro Leu Asp Cys Glu Val Asn Asn Asn Gly Ser Asp Arg Ala 995 1000 1005 Val His Ser Lys Ser Ser Thr Ala Val Tyr Leu Ala Glu Gly Gly Thr 1010 1015 1020 Ala Thr Thr Thr Val Ser Lys Asp Ile Gly Met Asn Cys Leu 1025 1030 1035 (2) INFORMATION FOR SEQ ID NO:13: (i) SEQUENCE CHARACTERISTICS: wU W/I1ZUiM PCT/US98/09519 88 (A) LENGTH: 2402 base pairs (B) TYPE: nucleic acid (C) STRANDEDNESS: double (D) TOPOLOGY: linear (ii) MOLECULE TYPE: cDNA (ix) FEATURE: (A) NAME/KEY: CDS (B) LOCATION: join(ll..1606) (xi) SEQUENCE DESCRIPTION: SEQ ID NO:13: GAATCAGACA ATG ACT CAG CTA TAC ACT TAC ATC AGA TTA CTG GGA GCC 49 Met Thr Gln Leu Tyr Thr Tyr Ile Arg Leu Leu Gly Ala 1 5 10 TGT CTG TTC ATC ATT TCT CAT GTT CAA GGG CAG AAT CTA GAT AGT ATG 97 Cys Leu Phe Ile Ile Ser His Val Gln Gly Gln Asn Leu Asp Ser Met 15 20 25 CTC CAT GGC ACT GGT ATG AAA TCA GAC TTG GAC CAG AAG AAG CCA GAA 145 Leu His Gly Thr Gly Met Lys Ser Asp Leu Asp Gln Lys Lys Pro Glu 30 35 40 45 AAT GGA GTG ACT TTA GCA CCA GAG GAT ACC TTG CCT TTC TTA AAG TGC 193 Asn Gly Val Thr Leu Ala Pro Glu Asp Thr Leu Pro Phe Leu Lys Cys 50 55 60 TAT TGC TCA GGA CAC TGC CCA GAT GAT GCT ATT AAT AAC ACA TGC ATA 241 Tyr Cys Ser Gly His Cys Pro Asp Asp Ala Ile Asn Asn Thr Cys Ile 65 70 75 ACT AAT GGC CAT TGC TTT GCC ATT ATA GAA GAA GAT GAT CAG GGA GAA 289 Thr Asn Gly His Cys Phe Ala Ile Ile Glu Glu Asp Asp Gln Gly Glu 80 85 90 ACC ACA TTA ACT TCT GGG TGT ATG AAG TAT GAA GGC TCT GAT TTT CAA 337 Thr Thr Leu Thr Ser Gly Cys Met Lys Tyr Glu Gly Ser Asp Phe Gln 95 100 105 TGC AAG GAT TCA CCG AAA GCC CAG CTA CGC AGG ACA ATA GAA TGT TGT 385 Cys Lys Asp Ser Pro Lys Ala Gln Leu Arg Arg Thr Ile Glu Cys Cys 110 115 120 125 CGG ACC AAT TTG TGC AAC CAG TAT TTG CAG CCT ACA CTG CCC CCT GTT 433 Arg Thr Asn Leu Cys Asn Gln Tyr Leu Gln Pro Thr Leu Pro Pro Val 130 135 140 GTT ATA GGT CCG TTC TTT GAT GGC AGC ATC CGA TGG CTG GTT GTG CTC 481 Val Ile Gly Pro Phe Phe Asp Gly Ser Ile Arg Trp Leu Val Val Leu 145 150 155 wu ai/3.ua PCT/US98/09519 89 ATT TCC ATG GCT GTC TGT ATA GTT GCT ATG ATC ATC TTC TCC AGC TGC 529 Ile Ser Met Ala Val Cys Ile Val Ala Met Ile Ile Phe Ser Ser Cys 160 165 170 TTT TGC TAT AAG CAT TAT TGT AAG AGT ATC TCA AGC AGG GGT CGT TAC 577 Phe Cys Tyr Lys His Tyr Cys Lys Ser Ile Ser Ser Arg Gly Arg Tyr 175 180 185 AAC CGT GAT TTG GAA CAG GAT GAA GCA TTT ATT CCA GTA GGA GAA TCA 625 Asn Arg Asp Leu Glu Gln Asp Glu Ala Phe Ile Pro Val Gly Glu Ser 190 195 200 205 TTG AAA GAC CTG ATT GAC CAG TCC CAA AGC TCT GGG AGT GGA TCT GGA 673 Leu Lys Asp Leu Ile Asp Gln Ser Gln Ser Ser Gly Ser Gly Ser Gly 210 215 220 TTG CCT TTA TTG GTT CAG CGA ACT ATT GCC AAA CAG ATT CAG ATG GTT 721 Leu Pro Leu Leu Val Gln Arg Thr Ile Ala Lys Gln Ile Gln Met Val 225 230 235 CGG CAG GTT GGT AAA GGC CGC TAT GGA GAA GTA TGG ATG GGT AAA TGG 769 Arg Gln Val Gly Lys Gly Arg Tyr Gly Glu Val Trp Met Gly Lys Trp 240 245 250 CGT GGT GAA AAA GTG GCT GTC AAA GTG TTT TTT ACC ACT GAA GAA GCT 817 Arg Gly Glu Lys Val Ala Val Lys Val Phe Phe Thr Thr Glu Glu Ala 255 260 265 AGC TGG TTT AGA GAA ACA GAA ATC TAC CAG ACG GTG TTA ATG CGT CAT 865 Ser Trp Phe Arg Glu Thr Glu Ile Tyr Gln Thr Val Leu Met Arg His 270 275 280 285 GAA AAT ATA CTT GGT TTT ATA GCT GCA GAC ATT AAA GGC ACT GGT TCC 913 Glu Asn Ile Leu Gly Phe Ile Ala Ala Asp Ile Lys Gly Thr Gly Ser 290 295 300 TGG ACT CAG CTG TAT TTG ATT ACT GAT TAC CAT GAA AAT GGA TCT CTC 961 Trp Thr Gln Leu Tyr Leu Ile Thr Asp Tyr His Glu Asn Gly Ser Leu 305 310 315 TAT GAC TTC CTG AAA TGT GCC ACA CTA GAC ACC AGA GCC CTA CTC AAG 1009 Tyr Asp Phe Leu Lys Cys Ala Thr Leu Asp Thr Arg Ala Leu Leu Lys 320 325 330 TTA GCT TAT TCT GCT GCT TGT GGT CTG TGC CAC CTC CAC ACA GAA ATT 1057 Leu Ala Tyr Ser Ala Ala Cys Gly Leu Cys His Leu His Thr Glu Ile 335 340 345 TAT GGT ACC CAA GGG AAG CCT GCA ATT GCT CAT CGA GAC CTG AAG AGC 1105 Tyr Gly Thr Gln Gly Lys Pro Ala Ile Ala His Arg Asp Leu Lys Ser 350 355 360 365 AAA AAC ATC CTT ATT AAG AAA AAT GGA AGT TGC TGT ATT GCT GAC CTG 1153 Lys Asn Ile Leu Ile Lys Lys Asn Gly Ser Cys Cys Ile Ala Asp Leu 370 375 380 wu 95/uaI35 PCT/US98/09519 90 GGC CTA GCT GTT AAA TTC AAC AGT GAT ACA AAT GAA GTT GAC ATA CCC 1201 Gly Leu Ala Val Lys Phe Asn Ser Asp Thr Asn Glu Val Asp Ile Pro 385 390 395 TTG AAT ACC AGG GTG GGC ACC AAG CGG TAC ATG GCT CCA GAA GTG CTG 1249 Leu Asn Thr Arg Val Gly Thr Lys Arg Tyr Met Ala Pro Glu Val Leu 400 405 410 GAT GAA AGC CTG AAT AAA AAC CAT TTC CAG CCC TAC ATC ATG GCT GAC 1297 Asp Glu Ser Leu Asn Lys Asn His Phe Gln Pro Tyr Ile Met Ala Asp 415 420 425 ATC TAT AGC TTT GGT TTG ATC ATT TGG GAA ATG GCT CGT CGT TGT ATT 1345 Ile Tyr Ser Phe Gly Leu Ile Ile Trp Glu Met Ala Arg Arg Cys Ile 430 435 440 445 ACA GGA GGA ATC GTG GAG GAA TAT CAA TTA CCA TAT TAC AAC ATG GTG 1393 Thr Gly Gly Ile Val Glu Glu Tyr Gln Leu Pro Tyr Tyr Asn Met Val 450 455 460 CCC AGT GAC CCA TCC TAT GAG GAC ATG CGT GAG GTT GTG TGT GTG AAA 1441 Pro Ser Asp Pro Ser Tyr Glu Asp Met Arg Glu Val Val Cys Val Lys 465 470 475 CGC TTG CGG CCA ATC GTG TCT AAC CGC TGG AAC AGC GAT GAA TGT CTT 1489 Arg Leu Arg Pro Ile Val Ser Asn Arg Trp Asn Ser Asp Glu Cys Leu 480 485 490 CGA GCA GTT TTG AAG CTA ATG TCA GAA TGT TGG GCC CAT AAT CCA GCC 1537 Arg Ala Val Leu Lys Leu Met Ser Glu Cys Trp Ala His Asn Pro Ala 495 500 505 TCC AGA CTC ACA GCT TTG AGA ATC AAG AAG ACA CTT GCA AAA ATG GTT 1585 Ser Arg Leu Thr Ala Leu Arg Ile Lys Lys Thr Leu Ala Lys Met Val 510 515 520 525 GAA TCC CAG GAT GTA AAG ATT TGACAATTAA ACAATTTTGA GGGAGAATTT 1636 Glu Ser Gln Asp Val Lys Ile 530 AGACTGCAAG AACTTCTTCA CCCAAGGAAT GGGTGGGATT AGCATGGAAT AGGATGTTGA 1696 CTTGGTTTCC AGACTCCTTC CTCTACATCT TCACAGGCTG CTAACAGTAA ACCTTACCGC 1756 ACTCTACAGA ATACAAGATT GGAACTTGGA ACTTGGAACT TCAAACATGT CATTCTTTAT 1816 ATATGGACAG CTGTGTTTTA AATGTGGGGT TTTTGTGTTT TGCTTTCTTT GTTTTGTTTT 1876 GGTTTTGATG CTTTTTTGGT TTTTATGAAC TGCATCAAGA CTCCAATCCT GATAAGAAGT 1936 CTCTGGTCAA CCTCTGGGTA CTCACTATCC TGTCCATAAA GTGGTGCTTT CTGTGAAAGC 1996 CTTAAGAAAA TTAATGAGCT CAGCAGAGAT GGAAAAAGGC ATATTTGGCT TCTACCAGAG 2056 AAAACATCTG TCTGTGTTCT GTCTTTGTAA ACAGCCTATA GATTATGATC TCTTTGGGAT 2116 wu miun/ e PCT/US98/09519 91 ACTGCCTGGC TTATGATGGT GCACCATACC TTTGATATAC ATACCAGAAT TCTCTCCTGC 2176 CCTAGGGCTA AGAAGACAAG AATGTAGAGG TTGCACAGGA GGTATTTTGT GACCAGTGGT 2236 TTAAATTGCA ATATCTAGTT GGCAATCGCC AATTTCATAA AAGCCATCCA CCTTGTAGCT 2296 GTAGTAACTT CTCCACTGAC TTTATTTTTA GCATAATAGT TGTGAAGGCC AAACTCCATG 2356 TAAAGTGTCC ATAGACTTGG ACTGTTTTCC CCCAGCTCTG ATTACC 2402 (2) INFORMATION FOR SEQ ID NO:14: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 532 amino acids (B) TYPE: amino acid (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (xi) SEQUENCE DESCRIPTION: SEQ ID NO:14: Met Thr Gln Leu Tyr Thr Tyr Ile Arg Leu Leu Gly Ala Cys Leu Phe 1 5 10 15 Ile Ile Ser His Val Gln Gly Gln Asn Leu Asp Ser Met Leu His Gly 20 25 30 Thr Gly Met Lys Ser Asp Leu Asp Gln Lys Lys Pro Glu Asn Gly Val 35 40 45 Thr Leu Ala Pro Glu Asp Thr Leu Pro Phe Leu Lys Cys Tyr Cys Ser 50 55 60 Gly His Cys Pro Asp Asp Ala Ile Asn Asn Thr Cys Ile Thr Asn Gly 65 70 75 80 His Cys Phe Ala Ile Ile Glu Glu Asp Asp Gln Gly Glu Thr Thr Leu 85 90 95 Thr Ser Gly Cys Met Lys Tyr Glu Gly Ser Asp Phe Gln Cys Lys Asp 100 105 110 Ser Pro Lys Ala Gln Leu Arg Arg Thr Ile Glu Cys Cys Arg Thr Asn 115 120 125 Leu Cys Asn Gln Tyr Leu Gln Pro Thr Leu Pro Pro Val Val Ile Gly 130 135 140 Pro Phe Phe Asp Gly Ser Ile Arg Trp Leu Val Val Leu Ile Ser Met 145 150 155 160 Ala Val Cys Ile Val Ala Met Ile Ile Phe Ser Ser Cys Phe Cys Tyr 165 170 175 Lys His Tyr Cys Lys Ser Ile Ser Ser Arg Gly Arg Tyr Asn Arg Asp wJ w3a.isu a PCT/US98/09519 92 180 185 190 Leu Glu Gln Asp Glu Ala Phe Ile Pro Val Gly Glu Ser Leu Lys Asp 195 200 205 Leu Ile Asp Gin Ser Gln Ser Ser Gly Ser Gly Ser Gly Leu Pro Leu 210 215 220 Leu Val Gin Arg Thr Ile Ala Lys Gln Ile Gln Met Val Arg Gin Val 225 230 235 240 Gly Lys Gly Arg Tyr Gly Glu Val Trp Met Gly Lys Trp Arg Gly Glu 245 250 255 Lys Val Ala Val Lys Val Phe Phe Thr Thr Glu Glu Ala Ser Trp Phe 260 265 270 Arg Glu Thr Glu Ile Tyr Gln Thr Val Leu Met Arg His Glu Asn Ile 275 280 285 Leu Gly Phe Ile Ala Ala Asp Ile Lys Gly Thr Gly Ser Trp Thr Gln 290 295 300 Leu Tyr Leu Ile Thr Asp Tyr His Glu Asn Gly Ser Leu Tyr Asp Phe 305 310 315 320 Leu Lys Cys Ala Thr Leu Asp Thr Arg Ala Leu Leu Lys Leu Ala Tyr 325 330 335 Ser Ala Ala Cys Gly Leu Cys His Leu His Thr Glu Ile Tyr Gly Thr 340 345 350 Gln Gly Lys Pro Ala Ile Ala His Arg Asp Leu Lys Ser Lys Asn Ile 355 360 365 Leu Ile Lys Lys Asn Gly Ser Cys Cys Ile Ala Asp Leu Gly Leu Ala 370 375 380 Val Lys Phe Asn Ser Asp Thr Asn Glu Val Asp Ile Pro Leu Asn Thr 385 390 395 400 Arg Val Gly Thr Lys Arg Tyr Met Ala Pro Glu Val Leu Asp Glu Ser 405 410 415 Leu Asn Lys Asn His Phe Gln Pro Tyr Ile Met Ala Asp Ile Tyr Ser 420 425 430 Phe Gly Leu Ile Ile Trp Glu Met Ala Arg Arg Cys Ile Thr Gly Gly 435 440 445 Ile Val Glu Glu Tyr Gln Leu Pro Tyr Tyr Asn Met Val Pro Ser Asp 450 455 460 Pro Ser Tyr Glu Asp Met Arg Glu Val Val Cys Val Lys Arg Leu Arg 465 470 475 480 wu wasu0a PCT/US98/09519 93 Pro Ile Val Ser Asn Arg Trp Asn Ser Asp Glu Cys Leu Arg Ala Val 485 490 495 Leu Lys Leu Met Ser Glu Cys Trp Ala His Asn Pro Ala Ser Arg Leu 500 505 510 Thr Ala Leu Arg Ile Lys Lys Thr Leu Ala Lys Met Val Glu Ser Gln 515 520 525 Asp Val Lys Ile 530 (2) INFORMATION FOR SEQ ID NO:15: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 2252 base pairs (B) TYPE: nucleic acid (C) STRANDEDNESS: double (D) TOPOLOGY: linear (ii) MOLECULE TYPE: cDNA (ix) FEATURE: (A) NAME/KEY: CDS (B) LOCATION: join(355..1860) (xi) SEQUENCE DESCRIPTION: SEQ ID NO:15: GTTTTCCAGC AGACTGATGC TATAAATGCT CCACAACATG GAGAATGGTT TGGGTTGGAA 60 GTAGACTTAA AGACCATCTA TGTGTGGGGA TACCTCCCAC TAGATCAGGC TGCTCAGGGC 120 CCCATTCACC ACCTCCAGGG ACGGGGTAGC CACTGCTTCT CTGAGCAACC TGAGCAACTT 180 CCTCACAGTG AAGAGTTCCT CCTGTATCCG AGGGTGGAGT TCATTTCTTT TGTCCTTGGA 240 AGTTGAATAG CAGAAAGGGA CATTTCAGCT TTTCTTGATA AAGGTTACAT CCATTTTACT 300 TAGACTACAA GACGAAGATT TCTGAAAATT GAGATCTTTA GTTTTCTGGA CAAG ATG 357 Met 1 CCC TTG CTT AGC TCC AGC AAG TTG AGC ATG GAG AGC AGA AAA GAA GAT 405 Pro Leu Leu Ser Ser Ser Lys Leu Ser Met Glu Ser Arg Lys Glu Asp 5 10 15 AGT GAG GGC ACA GCA CCT GCC CCT CCA CAG AAG AAG CTG TCA TGT CAG 453 Ser Glu Gly Thr Ala Pro Ala Pro Pro Gln Lys Lys Leu Ser Cys Gln 20 25 30 TGC CAC CAC CAT TGT CCT GAG GAC TCA GTC AAC AGC ACC TGC AGC ACT 501 Cys His His His Cys Pro Glu Asp Ser Val Asn Ser Thr Cys Ser Thr 35 40 45 wo W5in.Uas PCT/US98/09519 94 GAT GGC TAC TGC TTC ACC ATA ATA GAA GAA GAT GAT TCT GGT GGA CAT 549 Asp Gly Tyr Cys Phe Thr Ile Ile Glu Glu Asp Asp Ser Gly Gly His 50 55 60 65 TTG GTC ACC AAA GGA TGT CTA GGA TTA GAG GGC TCG GAC TTC CAG TGT 597 Leu Val Thr Lys Gly Cys Leu Gly Leu Glu Gly Ser Asp Phe Gln Cys 70 75 80 CGG GAC ACT CCT ATT CCA CAC CAA AGA AGA TCT ATT GAA TGC TGC ACA 645 Arg Asp Thr Pro Ile Pro His Gln Arg Arg Ser Ile Glu Cys Cys Thr 85 90 95 GGC CAA GAT TAC TGT AAC AAA CAT CTT CAC CCA ACG CTG CCA CCA CTG 693 Gly Gln Asp Tyr Cys Asn Lys His Leu His Pro Thr Leu Pro Pro Leu 100 105 110 AAA AAT CGA GAC TTT GCT GAA GGA AAC ATT CAC CAT AAG GCC CTG CTG 741 Lys Asn Arg Asp Phe Ala Glu Gly Asn Ile His His Lys Ala Leu Leu 115 120 125 ATC TCG GTG ACT GTC TGT AGT ATA CTA CTG GTG CTT ATC ATC ATA TTC 789 Ile Ser Val Thr Val Cys Ser Ile Leu Leu Val Leu Ile Ile Ile Phe 130 135 140 145 TGC TAC TTC AGG TAC AAG CGG CAA GAA GCC AGG CCC CGC TAC AGC ATC 837 Cys Tyr Phe Arg Tyr Lys Arg Gln Glu Ala Arg Pro Arg Tyr Ser Ile 150 155 160 GGG CTG GAG CAG GAC GAG ACC TAC ATT CCC CCT GGA GAA TCC CTG AAG 885 Gly Leu Glu Gln Asp Glu Thr Tyr Ile Pro Pro Gly Glu Ser Leu Lys 165 170 175 GAT CTG ATC GAG CAG TCC CAG AGC TCA GGC AGC GGC TCC GGG CTC CCT 933 Asp Leu Ile Glu Gln Ser Gln Ser Ser Gly Ser Gly Ser Gly Leu Pro 180 185 190 CTC CTG GTT CAA AGG ACC ATA GCA AAA CAG ATT CAG ATG GTA AAA CAG 981 Leu Leu Val Gln Arg Thr Ile Ala Lys Gln Ile Gln Met Val Lys Gln 195 200 205 ATT GGA AAA GGT CGC TAT GGG GAA GTC TGG ATG GGA AAG TGG CGT GGC 1029 Ile Gly Lys Gly Arg Tyr Gly Glu Val Trp Met Gly Lys Trp Arg Gly 210 215 220 225 GAA AAG GTA GCT GTC AAA GTG TTT TTT ACC ACG GAG GAG GCC AGC TGG 1077 Glu Lys Val Ala Val Lys Val Phe Phe Thr Thr Glu Glu Ala Ser Trp 230 235 240 TTC AGA GAA ACA GAA ATC TAC CAA ACT GTC CTG ATG AGG CAT GAA AAT 1125 Phe Arg Glu Thr Glu Ile Tyr Gln Thr Val Leu Met Arg His Glu Asn 245 250 255 ATT CTC GGA TTC ATT GCG GCA GAC ATT AAA GGC ACA GGC TCT TGG ACC 1173 Ile Leu Gly Phe Ile Ala Ala Asp Ile Lys Gly Thr Gly Ser Trp Thr 260 265 270 wu YoI1muo PCT/U59/US 9519 95 CAA CTG TAT CTC ATC ACT GAC TAT CAT GAG AAT GGC TCC CTT TAC GAT 1221 Gln Leu Tyr Leu Ile Thr Asp Tyr His Glu Asn Gly Ser Leu Tyr Asp 275 280 285 TAC CTA AAA TCC ACC ACC CTG GAC ACA AAA GGC ATG CTA AAA TTG GCT 1269 Tyr Leu Lys Ser Thr Thr Leu Asp Thr Lys Gly Met Leu Lys Leu Ala 290 295 300 305 TAC TCC TCT GTT AGT GGC TTG TGC CAC CTA CAT ACA GGG ATC TTC AGT 1317 Tyr Ser Ser Val Ser Gly Leu Cys His Leu His Thr Gly Ile Phe Ser 310 315 320 ACC CAA GGC AAA CCG GCT ATT GCC CAC CGT GAT CTA AAA AGT AAG AAC 1365 Thr Gln Gly Lys Pro Ala Ile Ala His Arg Asp Leu Lys Ser Lys Asn 325 330 335 ATC CTG GTG AAA AAG AAC GGA ACC TGC TGT ATA GCA GAT TTG GGC TTG 1413 Ile Leu Val Lys Lys Asn Gly Thr Cys Cys Ile Ala Asp Leu Gly Leu 340 345 350 GCT GTT AAA TTT ATT AGT GAT ACA AAT GAG GTA GAC ATC CCT CCA AAC 1461 Ala Val Lys Phe Ile Ser Asp Thr Asn Glu Val Asp Ile Pro Pro Asn 355 360 365 ACC CGC GTA GGA ACA AAA CGC TAT ATG CCT CCT GAG GTG CTG GAT GAA 1509 Thr Arg Val Gly Thr Lys Arg Tyr Met Pro Pro Glu Val Leu Asp Glu 370 375 380 385 AGC TTG AAC AGA AAT CAC TTT CAG TCG TAC ATC ATG GCT GAT ATG TAC 1557 Ser Leu Asn Arg Asn His Phe Gln Ser Tyr Ile Met Ala Asp Met Tyr 390 395 400 AGC TTT GGA CTC ATC CTT TGG GAG ATA GCC AGG AGA TGT GTG TCA GGA 1605 Ser Phe Gly Leu Ile Leu Trp Glu Ile Ala Arg Arg Cys Val Ser Gly 405 410 415 GGA ATA GTG GAA GAA TAC CAG CTC CCA TAT CAC GAC CTT GTC CCC AGT 1653 Gly Ile Val Glu Glu Tyr Gln Leu Pro Tyr His Asp Leu Val Pro Ser 420 425 430 GAC CCC TCC TAC GAG GAC ATG AGG GAG ATT GTG TGC ATC AAA AGG CTA 1701 Asp Pro Ser Tyr Glu Asp Met Arg Glu Ile Val Cys Ile Lys Arg Leu 435 440 445 CGT CCT TCA TTC CCC AAC AGA TGG AGC AGC GAT GAG TGC CTG CGG CAG 1749 Arg Pro Ser Phe Pro Asn Arg Trp Ser Ser Asp Glu Cys Leu Arg Gln 450 455 460 465 ATG GGG AAG CTC ATG ATG GAG TGC TGG GCC CAT AAC CCT GCA TCC CGG 1797 Met Gly Lys Leu Met Met Glu Cys Trp Ala His Asn Pro Ala Ser Arg 470 475 480 CTC ACA GCC CTA CGA GTC AAA AAA ACA CTT GCC AAA ATG TCA GAG TCG 1845 Leu Thr Ala Leu Arg Val Lys Lys Thr Leu Ala Lys Met Ser Glu Ser 485 490 495 wu ~waazua PCT/US98/09519 96 CAG GAC ATT AAG CTC TGATGGAGCA AAAACAGCTC CTTCTCGTGA AGACCCATGG 1900 Gin Asp Ile Lys Leu 500 AAACAGACTT TCTCTTGCAG GCAGAAGTCA TGGAGAGGTG CTGATAAGTA CCCTGAGTGC 1960 AGTCATATTT AAGAGCAACT GTTTGTTTGA CAGCTTTGAG GAGACTGTTC TTGGCAAAAT 2020 CAGCTGAATT TTGGCATGCA AGGTTGGGAG AGGCTTATCT GCCCTTGTTT ACACAGGGAT 2080 ATACAGTTTT AGTAACTGGT TTAAGGTTAT GCATGTTGCT TTCCGTGAAA GCCACTTATT 2140 ATTTTATTAT TATTGTTATT ATTATTATTT TGATTGTTTT AAAAGATACT GCTTTAAATT 2200 TTATGAAAAT AAAACCCTTT GGTTAGAAGA AAAAAAGATG TATATTGTTA CA 2252 (2) INFORMATION FOR SEQ ID NO:16: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 502 amino acids (B) TYPE: amino acid (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (xi) SEQUENCE DESCRIPTION: SEQ ID NO:16: Met Pro Leu Leu Ser Ser Ser Lys Leu Ser Met Glu Ser Arg Lys Glu 1 5 10 15 Asp Ser Glu Gly Thr Ala Pro Ala Pro Pro Gin Lys Lys Leu Ser Cys 20 25 30 Gin Cys His His His Cys Pro Glu Asp Ser Val Asn Ser Thr Cys Ser 35 40 45 Thr Asp Gly Tyr Cys Phe Thr Ile Ile Glu Glu Asp Asp Ser Gly Gly 50 55 60 His Leu Val Thr Lys Gly Cys Leu Gly Leu Glu Gly Ser Asp Phe Gin 65 70 75 80 Cys Arg Asp Thr Pro Ile Pro His Gin Arg Arg Ser Ile Glu Cys Cys 85 90 95 Thr Gly Gin Asp Tyr Cys Asn Lys His Leu His Pro Thr Leu Pro Pro 100 105 110 Leu Lys Asn Arg Asp Phe Ala Glu Gly Asn Ile His His Lys Ala Leu 115 120 125 Leu Ile Ser Val Thr Val Cys Ser Ile Leu Leu Val Leu Ile Ile Ile 130 135 140 Phe Cys Tyr Phe Arg Tyr Lys Arg Gin Glu Ala Arg Pro Arg Tyr Ser wo 98/52U8 PCT/US98/09519 97 145 150 155 160 Ile Gly Leu Glu Gln Asp Glu Thr Tyr Ile Pro Pro Gly Glu Ser Leu 165 170 175 Lys Asp Leu Ile Glu Gln Ser Gln Ser Ser Gly Ser Gly Ser Gly Leu 180 185 190 Pro Leu Leu Val Gln Arg Thr Ile Ala Lys Gln Ile Gin Met Val Lys 195 200 205 Gin Ile Gly Lys Gly Arg Tyr Gly Glu Val Trp Met Gly Lys Trp Arg 210 215 220 Gly Glu Lys Val Ala Val Lys Val Phe Phe Thr Thr Glu Glu Ala Ser 225 230 235 240 Trp Phe Arg Glu Thr Glu Ile Tyr Gln Thr Val Leu Met Arg His Glu 245 250 255 Asn Ile Leu Gly Phe Ile Ala Ala Asp Ile Lys Gly Thr Gly Ser Trp 260 265 270 Thr Gln Leu Tyr Leu Ile Thr Asp Tyr His Glu Asn Gly Ser Leu Tyr 275 280 285 Asp Tyr Leu Lys Ser Thr Thr Leu Asp Thr Lys Gly Met Leu Lys Leu 290 295 300 Ala Tyr Ser Ser Val Ser Gly Leu Cys His Leu His Thr Gly Ile Phe 305 310 315 320 Ser Thr Gln Gly Lys Pro Ala Ile Ala His Arg Asp Leu Lys Ser Lys 325 330 335 Asn Ile Leu Val Lys Lys Asn Gly Thr Cys Cys Ile Ala Asp Leu Gly 340 345 350 Leu Ala Val Lys Phe Ile Ser Asp Thr Asn Glu Val Asp Ile Pro Pro 355 360 365 Asn Thr Arg Val Gly Thr Lys Arg Tyr Met Pro Pro Glu Val Leu Asp 370 375 380 Glu Ser Leu Asn Arg Asn His Phe Gln Ser Tyr Ile Met Ala Asp Met 385 390 395 400 Tyr Ser Phe Gly Leu Ile Leu Trp Glu Ile Ala Arg Arg Cys Val Ser 405 410 415 Gly Gly Ile Val Glu Glu Tyr Gln Leu Pro Tyr His Asp Leu Val Pro 420 425 430 Ser Asp Pro Ser Tyr Glu Asp Met Arg Glu Ile Val Cys Ile Lys Arg 435 440 445 WO 9I/52UiS PCT/US98/09519 98 Leu Arg Pro Ser Phe Pro Asn Arg Trp Ser Ser Asp Glu Cys Leu Arg 450 455 460 Gln Met Gly Lys Leu Met Met Glu Cys Trp Ala His Asn Pro Ala Ser 465 470 475 480 Arg Leu Thr Ala Leu Arg Val Lys Lys Thr Leu Ala Lys Met Ser Glu 485 490 495 Ser Gln Asp Ile Lys Leu 500 wu 95/iUiS PCT/US98/09519 99 (2) INFORMATION FOR SEQ ID NO:17: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 26 base pairs (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (xi) SEQUENCE DESCRIPTION: SEQ ID NO:17: CCGGAATTCG TIGCIGTIAA RRWNYT 26 (2) INFORMATION FOR SEQ ID NO:18: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 30 base pairs (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (xi) SEQUENCE DESCRIPTION: SEQ ID NO:18: TGCTCTAGAC ATRTAICKIB BIGTICCNAC 30 (2) INFORMATION FOR SEQ ID NO:19: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 19 base pairs (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (xi) SEQUENCE DESCRIPTION: SEQ ID NO:19: CGAGCGCTTC ACCCACTTG 19 (2) INFORMATION FOR SEQ ID NO:20: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 19 base pairs (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear wo 98/52uiS PCT/US98/09519 100 (xi) SEQUENCE DESCRIPTION: SEQ ID NO:20: CACCACGACA CCACGGCAC 19 (2) INFORMATION FOR SEQ ID NO:21: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 25 base pairs (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (xi) SEQUENCE DESCRIPTION: SEQ ID NO:21: ATCGTCGACC ATGACGGCGC CCTGG 25 (2) INFORMATION FOR SEQ ID NO:22: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 18 base pairs (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear (xi) SEQUENCE DESCRIPTION: SEQ ID NO:22: GGGCGGAGGC CCCGGGTC 18

Claims

1. A method for determining whether a compound is capable of binding to a BMP receptor kinase protein complex, wherein the complex is comprised of a) a BMP; b) a BMP receptor kinase protein selected from BRK-2 (SEQ ID NO: 16) or BRK-1 (SEQ ID NO:14), a soluble fragment of BRK-2, a soluble fragment of BRK-1, an incomplete receptor kinase fragment of BRK-1, an incomplete receptor kinase fragment of of BRK-2; c) an ActRIIB receptor comprising amino acids 124 to 131 of SEQ ID NO: 2, or SEQ ID NO: 4, or a soluble fragment thereof, or an incomplete receptor kinase fragment thereof; the method comprising introducing a sample comprising the compound to the complex and allowing the compound to bind to the complex.

2. The method of Claim 1 wherein the BMP binding is determined using a cell co-transfected with an expression vector comprising a DNA sequence that codes for BMP receptor kinase protein BRK-1, SEQ ID NO:13, or a DNA sequence that codes for a soluble fragment thereof, or codes for an incomplete receptor kinase fragment thereof, and an expression vector comprising a DNA sequence that codes for the ActRIIB protein, selected from SEQ ID NO: 1 or SEQ ID NO:3 or a DNA sequence that codes for a soluble fragment thereof, or codes for an incomplete receptor kinase fragment thereof. WO 98/52038 PCT/US98/09519 102

3. The method of any preceding claim, wherein the BMP receptor kinase protein is selected from BRK-1 which has the amino acid sequence SEQ ID NO:14 or a soluble fragment of BRK-1, or an incomplete receptor kinase fragment of BRK-1; and BRK-2 which has the amino acid sequence SEQ ID NO:16 or a soluble fragment of BRK-2, or an incomplete receptor kinase fragment of BRK-2.

4. The method of any preceding claim, wherein the ActRIIB protein has the amino acid sequence is ActRIII, and has the amino acid sequence SEQ ID NO:2 or is ActRIIB 2 and has the amino acid sequence SEQ ID NO:4, or a soluble fragment thereof, or an incomplete receptor kinase fragment thereof.

5. The method of Claim 1, wherein the BMP is BMP-2 or BMP-4.

6. A host cell co-transfected with an expression vector comprising a DNA sequence that codes for BMP receptor kinase protein BRK-1, SEQ ID NO:13, or a DNA sequence that codes for a soluble fragment thereof, or codes for an incomplete receptor kinase fragment thereof, and an expression vector comprising a DNA sequence that codes for the ActRIIB protein, selected from SEQ ID NO: 1 or SEQ ID NO:3 or a DNA sequence that codes for a soluble fragment thereof, or codes for an incomplete receptor kinase fragment thereof; such proteins or fragment useful in the method of any preceding claims.

7. A method for determining the concentration of a BMP receptor ligand in a clinical sample, the method comprising: a. combining the clinical sample comprising the ligand with a BMP receptor kinase protein complex and a labeled BMP; b. allowing the labeled BMP to bind to the complex in the presence of the sample; and WO 98/52038 PCT/US98/09519 103 c. comparing with a standard curve prepared with known concentration of a BMP ligand; wherein the BMP receptor kinase protein complex is comprised of a BMP receptor kinase protein selected from BRK-2 (SEQ ID NO:16) or BRK-1 (SEQ ID NO:14), a soluble fragment of BRK-2, a soluble fragment of BRK-1, an incomplete receptor kinase fragment of BRK-1, or an incomplete receptor kinase fragment of BRK-2; and an ActRIIB receptor comprising amino acids 124 to 131 of SEQ ID NO: 2, or SEQ ID NO: 4, a soluble fragment thereof, or an incomplete receptor kinase fragment thereof.

8. The method of any preceding claim wherein the BMP binding is determined using a cell co-transfected with an expression vector comprising a DNA sequence that codes for BMP receptor kinase protein BRK-1, SEQ ID NO:13, or a DNA sequence that codes for a soluble fragment thereof, or codes for an incomplete receptor kinase fragment thereof, and an expression vector comprising a DNA sequence that codes for the ActRIIB protein, selected from SEQ ID NO: I or SEQ ID NO:3 or a DNA sequence that codes for a soluble fragment thereof, or codes for an incomplete receptor kinase fragment thereof.

9. The method of any preceding claim, wherein the BMP receptor kinase protein is the soluble fragment of BRK-2 or BRK-1 (SEQ ID NO: 16) or the soluble fragment of BRK-1 or BRK-2 (SEQ ID NO:14). WO 98/52038 PCT/US98/09519 104

10. A method for determining whether a test compound produces a signal upon binding to a BMP receptor protein complex, the method comprising: (a) labeling BMP receptor protein complex expressing cells with 3 2 p, wherein the cells have been transfected with a DNA sequence coding for a BMP, a BMP receptor kinase protein BRK-2 (SEQ ID NO:15) or BRK-1 (SEQ ID NO:13), an ActRIIB receptor comprising DNA encoding amino acids 124 to 131 of SEQ ID NO: 2, or SEQ ID NO: 4, (b) culturing: (i) a first set of the cells in the presence of the test compound, and (ii) a second set of the cells in the absence of the test compound; (c) quantitating via autoradiography any phosphorylated proteins produced from step (b); and (d) comparing the amount of phosphorylated proteins quantitated in step (c) from the first set of cells to the amount of phosphorylated proteins quantitated in step (c) for the second set of cells.

11. A method for determining whether a test compound produces a signal upon binding to a BMP receptor protein complex, the method comprising: (a) transfecting BMP receptor protein complex expressing cells with a luciferase reporter gene in conjunction with a beta-galactosidase gene, wherein the cells have been transfected with a DNA sequence coding for a BMP, a BMP receptor kinase protein BRK-2 (SEQ ID NO:15) or BRK-1 (SEQ ID NO:13), an ActRIIB receptor comprising DNA encoding amino acids 124 to 131 of SEQ ID NO: 2, or SEQ ID NO: 4; (b) culturing (i) a first set of the cells in the presence of the test compound, and (ii) a second set of the cells in the absence of the test compound; WO 98/52038 PCT/US98/09519 105 (c) quantitating via the arbitrary light units the level of luciferase activity produced by activation of the luciferase enzyme that results from stimulation of the reporter construct produced from step (b); and (d) comparing the amount of arbitrary light units quantitated in step (c) from the first set of cells to the amount of arbitrary light units quantitated in step (c) for the second set of cells.