AU2002300443B2 - Methods for Creating Transgenic animals - Google Patents

Methods for Creating Transgenic animals Download PDF

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AU2002300443B2
AU2002300443B2 AU2002300443A AU2002300443A AU2002300443B2 AU 2002300443 B2 AU2002300443 B2 AU 2002300443B2 AU 2002300443 A AU2002300443 A AU 2002300443A AU 2002300443 A AU2002300443 A AU 2002300443A AU 2002300443 B2 AU2002300443 B2 AU 2002300443B2
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Robert D. Bremel
Jane C. Burns
Anthony W.S. Chan
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Wisconsin Alumni Research Foundation
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S&F Ref: 442283D1
AUSTRALIA
PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT
ORIGINAL
Name and Address of Applicant: Actual Inventor(s): Address for Service: Invention Title: Wisconsin Alumni Research Foundation 614 Walnut Street Madison Wisconsin 53705-7365 United States of America Robert D. Bremel Anthony W. S. Chan Jane C. Bums Spruson Ferguson St Martins Tower,Level 31 Market Street Sydney NSW 2000 (CCN 3710000177) Methods for Creating Transgenic Animals The following statement is a full description of this invention, including the best method of performing it known to me/us:- 5845c Methods for Creating Transgenic Animals Field of the Invention The present invention relates to improved methods for the generation of transgenic non-human animals. In particular, the present invention relates to the introduction of retroviral particles into the perivitelline space of gametes, zygotes and early stage embryos to allow the insertion of genetic material into the genome of the recipient gamete or embryo.
Background The ability to alter the genetic make-up of animals, such as domesticated mammals such as cows, pigs and sheep, allows a number of commercial applications. These applications include the production of animals which express large quantities of exogenous proteins in an easily harvested form expression into the milk), the production of animals which are resistant to infection by specific microorganisms and the production of animals having enhanced growth rates or reproductive performance.
Animals which contain exogenous DNA sequences in their genome are referred to as transgenic animals.
The most widely used method for the production of transgenic animals is the microinjection of DNA into the pronuclei of fertilized embryos. This method is efficient for the production of transgenic mice but is much less efficient for the production of transgenic animals using large mammals such as cows and sheep. For example, it has been reported that 1,000 to 2,000 bovine embryos at the pronuclear stage must be microinjected to produce a single transgenic cow at an estimate cost of more than $500,000 [Wall et al. (1992) J. Cell. Biochem. 49:113]. Furthermore, microinjection of pronuclei is more difficult when embryos from domestic livestock cattle, sheep, pigs) is employed as the pronuclei are often obscured by yolk material. While techniques for the visualization of the pronuclei are known centrifugation of the embryo to sediment the yolk), the injection of pronuclei is an invasive technique which requires a high degree of operator skill.
Alternative methods for the production include the infection of embryos with retroviruses or with retroviral vectors. Infection of both pre- and post-implantation mouse embryos with either wild-type or recombinant retroviruses has been reported [Janenich (1976) Proc. Natl. Acad Sci. USA 73:1260-1264; Janenich et al. (1981) Cell 24:519; Stuhlmann et al. (1984) Proc. Natl. Acad. Sci. USA 81:7151; Jahner et al. (1985) Proc. Natl.
Acad Sci. USA 82:6927-6931; Van der Putten, et al. (1985) Proc. Natl. Acad Sci. USA 82:6148-6152; Stewart, et al. (1987) EMBO J. 6:383-388]. The resulting transgenic animals are typically mosaic for the transgene since incorporation occurs only in a subset of cells which form the transgenic animal. The consequences of mosaic incorporation of retroviral sequences the transgene) include lack of transmission of the transgene to progeny due to failure of the retrovirus to integrate into the germ line, difficulty in detecting the presence of viral sequences in the founder mice in those cases where the infected cell contributes to only a small part of the fetus and difficulty in assessing the effect of the genes carried on the retrovirus.
In addition to the production of mosaic founder animals, infection of embryos with retrovirus (which is typically performed using embryos at the 8 cell stage or later) often results in the production of founder animals containing multiple copies of the retroviral provirus at different positions in the genome which generally will segregate in the offspring.
Infection of early mouse embryos by co-culturing early embryos with cells producing retroviruses requires enzymatic treatment to remove the zona pellucida [Hogan et al. (1994) in Manipulating the Mouse Embryo: A Laboratory Manual, 2nd Ed., Cold Spring Harbor Laboratory Press, Cold Spring Harbor, NY, pp. 251-252]. In contrast to mouse embryos, bovine embryos dissociate when removed from the zona pellucida. Therefore, infection protocols which remove the zona pellucida cannot be employed for the production of transgenic cattle or other animals whose embryos dissociate or suffer a significant decrease in viability upon removal of the zona pellucida ovine embryos).
An alternative means for infecting embryos with retroviruses is the injection of virus or virus-producing cells into the blastocoele of mouse embryos [Jahner, D. et al. (1982) Nature 298:623-628]. As is the case for infection of eight cell stage embryos, most of the founders produced by injection into the blastocoele will be mosaic. The introduction of transgenes into the germline of mice has been reported using.intrauterine retroviral infection of the midgestation mouse embryo [Jahner, D. et al. (1982) supra]. This technique suffers from a low efficiency of generation of transgenic animals and in addition produces animals which are mosaic for the transgene.
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I
Infection of bovine and ovine embryos with retroviruses or retroviral vectors to create transgenic animals has been reported. These protocols involve the micro-injection of retroviral particles or growth arrested mitomycin C-treated) cells which shed retroviral particles into the perivitelline space of fertilized eggs or early embryos [PCT International Application WO 90/08832 (1990) and Haskell and Bowen (1995) Mol.
Reprod. Dev. 40:386]. PCT International Application WO 90/08832 describes the injection of wild-type feline leukemia virus B into the perivitelline space of sheep embryos at the 2 to 8 cell stage. Fetuses derived from injected embryos were shown to contain multiple sites of integration. The efficiency of producing transgenic sheep was low (efficiency is defined as the number of transgenics produced compared to the number of embryos manipulated); only 4.2% of the injected embryos were found to be transgenic.
Haskell and Bowen (supra) describe the micro-injection of mitomycin C-treated cells producing retrovirus into the perivitelline space of 1 to 4 cell bovine embryos. The use of virus-producing cells precludes the delivery of a controlled amount of viral particles per embryo. The resulting fetuses contained between 2 and 12 proviruses and were shown to be mosaic for proviral integration sites, the presence of provirus, or both.
The efficiency of producing transgenic bovine embryos was low; only 7% of the injected embryos were found to be transgenic.
The art needs improved methods for the production of transgenic animals, particularly for the production oftransgenics using large domestic livestock animals. The ideal method would be simple to perform and less invasive than pronuclear injection, efficient, would produce mosaic transgenic founder animals at a low frequency and would result in the integration of a defined number of copies of the introduced sequences into the genome of the transgenic animal.
Summary of the Invention According to a first embodiment of the invention, there is provided a composition comprising a non-human mammalian unfertilized oocyte comprising a heterologous polynucleotide integrated into the genome of said oocyte, wherein the polynucleotide is introduced into the oocyte by microinjection into the perivitelline space, and wherein the heterologous polynucleotide is a retroviral vector.
According to a second embodiment of the invention, there is provided a method for introducing a heterologous polynucleotide into the genome of a non-human mammalian unfertilized [R:\PAL Specifications\4422831707I 2specdoc:gcc oocyte, comprising: a) providing: i) a non-human mammalian unfertilized egg comprising an oocyte having a plasma membrane and a zona pellucida, said plasma membrane and said zona pellucida s defining a perivitelline space; ii) an aqueous solution comprising a heterologous polynucleotide, wherein the heterologous polynucleotide is a retroviral vector; and b) introducing said solution comprising said heterologous polynucleotide into said perivitelline space under conditions which permit the introduction of said heterologous polynucleotide into the genome of said oocyte.
According to a third embodiment of the invention, there is provided a method for the production of a transgenic non-human animal comprising: a) providing: i) an unfertilized egg comprising an oocyte having a plasma membrane is and a zona pellucida, said plasma membrane and said zona pellucida defining a perivitelline space; ii) an aqueous solution containing infectious retrovirus; b) introducing said solution containing infectious retrovirus into said perivitelline space under conditions which permit the infection of said oocyte; and c) contacting said infected oocyte with sperm under conditions which permit the fertilization of said infected oocyte to produce an embryo.
The present invention provides improved methods and compositions for the production of transgenic non-human animals. In one embodiment, the present invention provides a composition comprising a non-human unfertilized oocyte comprising a heterologous oligonucleotide a heterologous polynucleotide) integrated into the genome of the oocyte. In a preferred embodiment the unfertilized oocyte is a prematuration oocyte. In another preferred embodiment the unfertilized oocyte is a prefertilization oocyte. The present invention is not limited by the nature of the heterologous oligonucleotide contained within the IR:\PA L Specifications\4422831707I2spec.doc:gcc genome of the oocyte. In a preferred embodiment, the heterologous oligonucleotide is the proviral form of a retroviral vector.
The invention is not limited by the nature of the retroviral vector employed.
Retroviral vectors containing a variety of genes may be employed. For example, the retroviral vector may contain sequences encoding proteins which modify growth rate, size and/or carcass composition bovine growth hormone or other growth hormones) or foreign proteins of commercial value that are expressed in, and harvested from, a particular tissue component blood or milk). The retroviral vector may contain genes that confer disease resistance to viruses or other microorganisms, including DNA sequences that are transcribed into RNA sequences that catalytically cleave specific RNAs ribozymes) such as viral RNAs and DNA sequences that are transcribed into anti-sense RNA of an essential gene of a pathogenic microorganism. The above protein-encoding genes and DNA sequences are examples of "genes of interest" The compositions of the present invention are not limited by the nature of the nonhuman animal employed to provide oocytes. In a preferred embodiment, the non-human animal is a mammal cows, pigs, sheep, goats, rabbits, rats, mice, etc.). In a particularly preferred embodiment, the non-human animal is a cow.
The present invention further provides a method for introducing a heterologous polynucleotide into the genome of a non-human unfertilized oocyte, comprising: a) providing: i) a non-human unfertilized egg comprising an oocyte having a plasma membrane and a zona pellucida, the plasma membrane and the zona pellucida defining a perivitelline space; ii) an aqueous solution comprising a heterologous polynucleotide; and b) introducing the solution comprising the heterologous polynucleotide into the perivitelline space under conditions which permit the introduction of the heterologous polynucleotide into the genome of the oocyte. The method of the present invention is not limited by the nature of the heterologous polynucleotide employed. In a preferred embodiment, the heterologous polynucleotide encodes a protein of interest. In a particularly preferred embodiment, the heterologous polynucleotide is contained within genome of a recombinant retrovirus.
The method of the present invention may be practiced using unfertilized eggs comprising a pre-maturation oocyte. Alternatively, the method of the present invention may employ pre-fertilization oocytes as the unfertilized egg.
When a recombinant retrovirus is employed infectious retroviral particles comprising the heterologous polynucleotide are preferentially employed. The method of the present -4invention is not limited by the nature of the infectious retrovirus employed to deliver nucleic acid sequences to an oocyte. Any retrovirus which is capable of infecting the species of oocyte to be injected may be employed. In a preferred embodiment, the infectious retrovirus comprises a heterologous membrane-associated protein. In a preferred embodiment, the heterologous membrane-associated protein is a G glycoprotein selected from a virus within the family Rhabdoviridae. In another preferred embodiment, the heterologous membraneassociated protein is selected from the group consisting of the G glycoprotein of vesicular stomatitis virus, Piry virus, Chandipura virus, Spring viremia of carp virus and Mokola virus.
In a particularly preferred embodiment, the heterologous membrane-associated protein is the G glycoprotein of vesicular stomatitis virus.
The method of the present invention is not limited by the nature of the non-human animal employed to provide oocytes. In a preferred embodiment, the non-human animal is a mammal cows, pigs, sheep, goats, rabbits, rats, mice, etc.). In a particularly preferred embodiment, the non-human animal is a cow.
The present invention further provides a method for the production of a transgenic non-human animal comprising: a) providing: i) an unfertilized egg comprising an oocyte having a plasma membrane and a zona pellucida, the plasma membrane and the zona pellucida defining a perivitelline space; ii) an aqueous solution containing infectious retrovirus; b) introducing the solution containing infectious retrovirus into the perivitelline space under conditions which permit the infection of the oocyte; and c) contacting the infected oocyte with sperm under conditions which permit the fertilization of the infected oocyte to produce an embryo. In a preferred embodiment, the method of the present invention further comprises, following the fertilization of the infected oocyte, the step of transferring the embryo into a hormonally sychronized non-human recipient animal a female animal hormonally sychronized to stimulate early pregnancy). In another preferred embodiment, the method comprises the step of allowing the transferred embryo to develop to term. In still another referred embodiment, at least one transgenic offspring is identified from the offspring allowed to develop to term.
The method of the present invention may be practiced using unfertilized eggs comprising a pre-maturation oocyte. Alteratively, the method of the present invention may employ pre-fertilization oocytes as the unfertilized egg.
When pre-maturation oocytes are employed in the method of the present invention, the method may further comprise, following the introduction of the solution containing infectious retrovirus into the pre-maturation oocyte, the further step of culturing the infected prematuration oocyte under conditions which permit the maturation of the pre-maturation oocyte.
The art is well aware of culture conditions which permit the in vitro maturation of prematuration oocytes from a variety of mammalian species.
The method of the present invention is not limited by the nature of the infectious retrovirus employed to deliver nucleic acid sequences to an oocyte. Any retrovirus which is capable of infecting the species of oocyte to be injected may be employed. In a preferred embodiment, the infectious retrovirus comprises a heterologous membrane-associated protein.
In a preferred embodiment, the heterologous membrane-associated protein is a G glycoprotein selected from a virus within the family Rhabdoviridae. In another preferred embodiment, the heterologous membrane-associated protein is selected from the group consisting of the G glycoprotein of vesicular stomatitis virus, Piry virus, Chandipura virus, Spring viremia of carp virus and Mokola virus. In a particularly preferred embodiment, the heterologous membraneassociated protein is the G glycoprotein of vesicular stomatitis virus.
The method of the present invention is not limited by the nature of the non-human animal employed to provide oocytes. In a preferred embodiment, the non-human animal is a mammal cows, pigs, sheep, goats, rabbits, rats, mice, etc.). In a particularly preferred embodiment, the non-human animal is a cow.
DESCRIPTION OF THE DRAWINGS Figure 1 provides a schematic showing the production of pre-maturation oocytes, prefertilization oocytes and fertilized oocytes (zygotes).
Figure 2 shows an autoradiogram of a Southern blot of genomic DNA isolated from the skin and blood of calves derived from pre-fertilization oocytes and zygotes which were injected with pseudotyped LSRNL retrovirus.
Figure 3 shows an ethidium bromide stained agarose gel containing electrophoresed PCR products which were amplified using neo gene primers or HBsAg primers from the blood and skin of calves derived from pre-fertilization oocytes and zygotes injected with pseudotyped LSRNL retrovirus.
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DEFINITIONS
To facilitate understanding of the invention, a number of terms are defined below.
As used herein, the term "egg" when used in reference to a mammalian egg, means an oocyte surrounded by a zona pellucida and a mass of cumulus cells (follicle cells) with their associated proteoglycan. The term "egg" is used in reference to eggs recovered from antral follicles in an ovary (these eggs comprise pre-maturation oocytes) as well as to eggs which have been released from an antral follicle (a ruptured follicle).
As used herein, the term "oocyte" refers to a female gamete cell and includes primary oocytes, secondary oocytes and mature, unfertilized ovum. An oocyte is a large cell having a large nucleus the germinal vesicle) surrounded by ooplasm. The ooplasm contains nonnuclear cytoplasmic contents including mRNA, ribosomes, mitochondria, yolk proteins, etc.
The membrane of the oocyte is referred to herein as the "plasma membrane." The term "pre-maturation oocyte" as used herein refers to a female gamete cell following the oogonia stage mitotic proliferation has occurred) that is isolated from an ovary by aspiration) but which has not been exposed to maturation medium in vitro.
Those of skill in the art know that the process of aspiration causes oocytes to begin the maturation process but that completion of the maturation process formation of a secondary oocyte which has extruded the first polar body) in vitro requires the exposure of the aspirated oocytes to maturation medium. Pre-maturation oocytes will generally be arrested at the first anaphase of meiosis.
The term "pre-fertilization oocyte" as used herein refers to a female gamete cell such as a pre-maturation oocyte following exposure to maturation medium in vitro but prior to exposure to sperm matured but not fertilized). The pre-fertilization oocyte has completed the first meiotic division, has released the first polar body and lacks a nuclear membrane (the nuclear membrane will not reform until fertilization occurs; after fertilization, the second meiotic division occurs along with the extrusion of the second polar body and the formation of the male and female pronuclei). Pre-fertilization oocytes may also be referred to as matured oocytes at metaphase II of the second meiosis.
The terms "unfertilized egg" or "unfertilized oocyte" as used herein refers to any female gamete cell which has not been fertilized and these terms encompass both prematuration and pre-fertilization oocytes.
The term "perivitelline space" refers to the space located between the zona pellucida and the plasma membrane of a mammalian egg or oocyte.
The term "infectious retrovirus" refers to a retroviral particle which is capable of entering a cell the particle contains a membrane-associated protein such as an envelope protein or a viral G glycoprotein which can bind to the host cell surface and facilitate entry of the viral particle into the cytoplasm of the host cell) and integrating the retroviral genome (as a double-stranded provirus) into the genome of the host cell.
Retroviral vectors can be used to transfer genes efficiently into host cells by exploiting the viral infectious process. Foreign or heterologous genes cloned inserted using molecular biological techniques) into the retroviral genome can be delivered efficiently to host cells which are susceptible to infection by the retrovirus. Through well known genetic manipulations, the replicative capacity of the retroviral genome can be destroyed. The resulting replication-defective vectors can be used to introduce new genetic material to a cell but they are unable to replicate. A helper virus or packaging cell line can be used to permit vector particle assembly and egress from the cell.
The terms "vector particle" or "retroviral particle" refer to viral-like particles that are capable of introducing nucleic acid into a cell through a viral-like entry mechanism.
The host range of a retroviral vector the range of cells that these vectors can infect) can be altered by including an envelope protein from another closely related virus.
The term "membrane-associated protein" refers to a protein a viral envelope glycoprotein or the G proteins of viruses in the Rhabdoviridae family such as VSV, Piry, Chandipura and Mokola) which are associated with the membrane surrounding a viral particle; these membrane-associated proteins mediate the entry of the viral particle into the host cell. The membrane associated protein may bind to specific cell surface protein receptors, as is the case for retroviral envelope proteins or the membrane-associated protein may interact with a phospholipid component of the plasma membrane of the host cell, as is the case for the G proteins derived from members of the Rhabdoviridae family.
The term "heterologous membrane-associated protein" refers to a membrane-associated protein which is derived from a virus which is not a member of the same viral class or family as that from which the nucleocapsid protein of the vector particle is derived. "Viral class or family" refers to the taxonomic rank of class or family, as assigned by the International Committee on Taxonomy of Viruses.
The term "Rhabdoviridae" refers to a family of enveloped RNA viruses that infect animals, including humans, and plants. The Rhabdoviridae family encompasses the genus Vesiculovirus which includes vesicular stomatitis virus (VSV), Cocal virus, Piry virus, -8- Chandipura virus, and Spring viremia of carp virus (seqeunces encoding the Spring viremia of carp virus are available under GenBank accession number U18101). The G proteins of viruses in the Vesiculovirus genera are virally-encoded integral membrane proteins that form externally projecting homotrimeric spike glycoproteins complexes that are required for receptor binding and membrane fusion. The G proteins of viruses in the Vesiculovirus genera have a covalently bound palmititic acid moiety. The amino acid sequences of the G proteins from the Vesiculoviruses are fairly well conserved. For example, the Piry virus G protein share about 38% identity and about 55% similarity with the VSV G proteins (several strains of VSV are known, Indiana, New Jersey, Orsay, San Juan, etc., and their G proteins are highly homologous). The Chandipura virus G protein and the VSV G proteins share about 37% identity and 52% similarity. Given the high degree of conservation (amino acid sequence) and the related functional characteristics binding of the virus to the host cell and fusion of membranes, including syncytia formation) of the G proteins of the Vesiculoviruses, the G proteins from non-VSV Vesiculoviruses may be used in place of the VSV G protein for the pseudotyping of viral particles. The G proteins of the Lyssa viruses (another genera within the Rhabdoviridae family) also share a fair degree of conservation with the VSV G proteins and function in a similar manner mediate fusion of membranes) and therefore may be used in place of the VSV G protein for the pseudotyping of viral particles. The Lyssa viruses include the Mokola virus and the Rabies viruses (several strains of Rabies virus are known and their G proteins have been cloned and sequenced). The Mokola virus G protein shares stretches of homology (particulary over the extracellular and transmembrane domains) with the VSV G proteins which show about 31% identity and 48% similarity with the VSV G proteins. Preferred G proteins share at least 25% identity, preferably at least 30% identity and most preferably at least 35% identity with the VSV G proteins. The VSV G protein from which New Jesery strain (the sequence of this G protein is provided in GenBank accession numbers M27165 and M21557) is employed as the reference VSV G protein.
The term "conditions which permit the maturation of a pre-maturation oocyte" refers to conditions of in vitro cell culture which permit the maturation of a pre-maturation oocyte to a mature ovum a pre-fertilization oocyte). These culture conditions permit and induce the events which are associated with maturation of the pre-maturation oocyte including stimulation of the first and second meiotic divisions. In vitro culture conditions which permit the maturation of pre-maturation oocytes from a variety of mammalian species cattle, -9hamster, pigs and goats) are well know to the art [see Parrish et al. (1985) Theriogenology 24:537; Rosenkrans and First (1994) J. Ani. Sci. 72:434; Bavister and Yanagimachi (1977) Biol. Reprod. 16:228; Bavister et al. (1983) Biol. Reprod. 28:235; Leibfried and Bavister (1982) J. Reprod. Fert. 66:87; Keskintepe et al. (1994) Zygote 2:97 Funahashi et al. (1994) J. Reprod. Fert. 101:159 and Funahashi et al. (1994) Biol. Reprod 50:1072].
DESCRIPTION OF THE INVENTION The present invention provides improved methods for the production of transgenic animals. The methods of the present invention provide, for the first time, the production of transgenic animals by the introduction of exogenous DNA into pre-maturation oocytes and mature, unfertilized oocytes pre-fertilization oocytes) using retroviral vectors which transduce dividing cells vectors derived from murine leukemia virus (MLV)].
The Description of the Invention is divided into the following sections: I. Retroviruses and Retroviral Vectors; II. Integration of Retroviral DNA; III. Introduction of Retroviral Vectors Into Gametes Before the Last Meiotic Division; and IV. Detection of the Retrovirus Following Injection Into Oocytes or Embryos.
I. Retroviruses and Retroviral Vectors Retroviruses (family Retroviridae) are divided into three groups: the spumaviruses human foamy virus); the lentiviruses human immunodeficiency virus and sheep visna virus) and the oncoviruses MLV, Rous sarcoma virus).
Retroviruses are enveloped surrounded by a host cell-derived lipid bilayer membrane) single-stranded RNA viruses which infect animal cells. When a retrovirus infects a cell, its RNA genome is converted into a double-stranded linear DNA form it is reverse transcribed). The DNA form of the virus is then integrated into the host cell genome as a provirus. The provirus serves as a template for the production of additional viral genomes and viral mRNAs. Mature viral particles containing two copies of genomic RNA bud from the surface of the infected cell. The viral particle comprises the genomic RNA, reverse transcriptase and other pol gene products inside the viral capsid (which contains the viral gag gene products) which is surrounded by a lipid bilayer membrane derived from the host cell containing the viral envelope glycoproteins (also referred to as membrane-associated proteins).
The organization of the genomes of numerous retroviruses is well known to the art and this has allowed the adaptation of the retroviral genome to produce retroviral vectors.
The production of a recombinant retroviral vector carrying a gene of interest is typically achieved in two stages. First, the gene of interest is inserted into a retroviral vector which contains the sequences necessary for the efficient expression of the gene of interest [including promoter and/or enhancer elements which may be provided by the viral long terminal repeats (LTRs) or by an internal promoter/enhancer and relevant splicing signals], sequences required for the efficient packaging of the viral RNA into infectious virions the packaging signal (Psi), the tRNA primer binding site the 3' regulatory sequences required for reverse transcription and the viral LTRs. The LTRs contain sequences required for the association of viral genomic RNA, reverse transcriptase and integrase functions, and sequences involved in directing the expression of the genomic RNA to be packaged in viral particles. For safety reasons, many recombinant retroviral vectors lack functional copies of the genes which are essential for viral replication (these essential genes are either deleted or disabled); the resulting virus is said to be replication defective.
Second, following the construction of the recombinant vector, the vector DNA is introduced into a packaging cell line. Packaging cell lines provide viral proteins required in trans for the packaging of the viral genomic RNA into viral particles having the desired host range the viral-encoded gag, pol and env proteins). The host range is controlled, in part, by the type of envelope gene product expressed on the surface of the viral particle.
Packaging cell lines may express ecotrophic, amphotropic or xenotropic envelope gene products. Alternatively, the packaging cell line may lack sequences encoding a viral envelope (env) protein. In this case the packaging cell line will package the viral genome into particles which lack a membrane-associated protein an env protein). In order to produce viral particles containing a membrane associated protein which will permit entry of the virus into a cell, the packaging cell line containing the retroviral sequences is transfected with sequences encoding a membrane-associated protein the G protein of vesicular stomatitis virus The transfected packaging cell will then produce viral particles which contain the membrane-associated protein expressed by the transfected packaging cell line; these viral particles which contain viral genomic RNA derived from one virus encapsidated by the envelope proteins of another virus are said to be pseudotyped virus particles.
Viral vectors, including recombinant retroviral vectors, provide a more efficient means of transferring genes into cells as compared to other techniques such as calcium 11 phosphate-DNA co-precipitation or DEAE-dextran-mediated transfection, electroporation or microinjection of nucleic acids. It is believed that the efficiency of viral transfer is due in part to the fact that the transfer of nucleic acid is a receptor-mediated process the virus binds to a specific receptor protein on the surface of the cell to be infected). In addition, the virally transferred nucleic acid once inside a cell integrates in controlled manner in contrast to the integration of nucleic acids which are not virally transferred; nucleic acids transferred by other means such as calcium phosphate-DNA co-precipitation are subject to rearrangement and degradation.
The most commonly used recombinant retroviral vectors are derived from the amphotropic Moloney murine leukemia virus (MoMLV) [Miller and Baltimore (1986) Mol.
Cell. Biol. 6:2895]. The MoMLV system has several advantages: 1) this specific retrovirus can infect many different cell types, 2) established packaging cell lines are available for the production of recombinant MoMLV viral particles and 3) the transferred genes are permanently integrated into the target cell chromosome. The established MoMLV vector systems comprise a DNA vector containing a small portion of the retroviral sequence (the viral long terminal repeat or "LTR" and the packaging or "psi" signal) and a packaging cell line. The gene to be transferred is inserted into the DNA vector. The viral sequences present on the DNA vector provide the signals necessary for the insertion or packaging of the vector RNA into the viral particle and for the expression of the inserted gene. The packaging cell line provides the viral proteins required for particle assembly [Markowitz et al. (1988) J.
Virol. 62:1120].
Despite these advantages, existing retroviral vectors based upon MoMLV are limited by several intrinsic problems: 1) they do not infect non-dividing cells [Miller et al., (1990) Mol. Cell. Biol. 10:4239], 2) they produce low titers of the recombinant virus [Miller and Rosman (1989) BioTechniques 7: 980 and Miller (1992) Nature 357: 455] and 3) they infect certain cell types human lymphocytes) with low efficiency [Adams et al. (1992) Proc.
Natl. Acad. Sci. USA 89:8981]. The low titers associated with MoMLV-based vectors has been attributed, at least in part, to the instability of the virus-encoded envelope protein.
Concentration of retrovirus stocks by physical means ultracentrifugation and ultrafiltration) leads to a severe loss of infectious virus.
The low titer and inefficient infection of certain cell types by MoMLV-based vectors has been overcome by the use of pseudotyped retroviral vectors which contain the G protein of VSV as the membrane associated protein. Unlike retroviral envelope proteins which bind 12to a specific cell surface protein receptor to gain entry into a cell, the VSV G protein interacts with a phospholipid component of the plasma membrane [Mastromarino et al. (1977) J. Gen.
Virol. 68:2359]. Because entry of VSV into a cell is not dependent upon the presence of specific protein receptors, VSV has an extremely broad host range. Pseudotyped retroviral vectors bearing the VSV G protein have an altered host range characteristic of VSV they can infect almost all species of vertebrate, invertebrate and insect cells). Importantly, VSV G-pseudotyped retroviral vectors can be concentrated 2000-fold or more by ultracentrifugation without significant loss of infectivity [Burns et al. (1993) Proc. Natl. Acad. Sci. USA 90:8033].
The VSV G protein has also been used to pseudotype retroviral vectors based upon the human immunodeficiency virus (HIV) [Naldini et al. (1996) Science 272:263]. Thus, the VSV G protein may be used to generate a variety of pseudotyped retroviral vectors and is not limited to vectors based on MoMLV.
The present invention is not limited to the use of the VSV G protein when a viral G protein is employed as the heterologous membrane-associated protein within a viral particle.
The G proteins of viruses in the Vesiculovirus genera other than VSV, such as the Piry and Chandipura viruses, that are highly homologous to the VSV G protein and, like the VSV G protein, contain covalently linked palmitic acid [Brun et al. (1995) Intervirol. 38:274 and Masters et al. (1990) Virol. 171:285]; thus, the G protein of the Piry and Chandipura viruses can be used in place of the VSV G protein for the pseudotyping of viral particles. In addition, the VSV G proteins of viruses within the Lyssa virus genera such as Rabies and Mokola viruses show a high degree of conservation (amino acid sequence as well as functional conservation) with the VSV G proteins. For example, the Mokola virus G protein has been shown to function in a manner similar to the VSV G protein to mediate membrane fusion) and therefore may be used in place of the VSV G protein for the pseudotyping of viral particles [Mebatsion et al. (1995) J. Virol. 69:1444]. The nucleotide sequence encoding the Piry G protein is provided in SEQ ID NO:5 and the amino acid sequence of the Piry G protein is provided in SEQ ID NO:6. The nucleotide sequence encoding the Chandipura G protein is provided in SEQ ID NO:7 and the amino acid sequence of the Chandipura G protein is provided in SEQ ID NO:8. The nucleotide sequence encoding the Mokola G protein is provided in SEQ ID NO:9 and the amino acid sequence of the Mokola G protein is provided in SEQ ID NO:10. Viral particles may be pseudotyped using either the Piry, Chandipura or Mokola G protein as described in Example 2 with the 13 WO 98/41615 exception that a plasmid containing sequences encoding either the Piry, Chandipura or Mokola G protein under the transcriptional control of a suitable promoter element the CMV intermediate-early promoter; numerous expression vectors containing the CMV IE promoter are available, such as the pcDNA3.1 vectors (Invitrogen)] is used in place of pHCMV-G. Sequences encoding other G proteins derived from other members of the Rhabdoviridae family may be used; sequences encoding numerous rhabdoviral G proteins are available from the GenBank database.
II. Integration of Retroviral DNA The majority of retroviruses can transfer or integrate a double-stranded linear form of the virus (the provirus) into the genome of the recipient cell only if the recipient cell is cycling dividing) at the time of infection. Retroviruses which have been shown to infect dividing cells exclusively, or more efficiently, include MLV, spleen necrosis virus, Rous sarcoma virus and human immunodeficiency virus (HIV; while HIV infects dividing cells more efficiently, HIV can infect non-dividing cells).
It has been shown that the integration of MLV virus DNA depends upon the host cell's progression through mitosis and it has been postulated that the dependence upon mitosis reflects a requirement for the breakdown of the nuclear envelope in order for the viral integration complex to gain entry into the nucleus [Roe et al. (1993) EMBO J. 12:2099].
However, as integration does not occur in cells arrested in metaphase, the breakdown of the nuclear envelope alone may not be sufficient to permit viral integration; there may be additional requirements such as the state of condensation of the genomic DNA (Roe et al., supra).
I. Introduction of Retroviral Vectors Into Gametes Before the Last Meiotic Division The nuclear envelope of a cell breaks down during meiosis as well as during mitosis.
Meiosis occurs only during the final stages of gametogenesis. The methods of the present invention exploit the breakdown of the nuclear envelope during meiosis to permit the integration of recombinant retroviral DNA and permit for the first time the use of unfertilized oocytes pre-fertilization and pre-maturation oocytes) as the recipient cell for retroviral gene transfer for the production of transgenic animals. Because infection of unfertilized 14oocytes permits the integration of the recombinant provirus prior to the division of the one cell embryo, all cells in the embryo will contain the proviral sequences.
Oocytes which have not undergone the final stages of gametogenesis are infected with the retroviral vector. The injected oocytes are then permitted to complete maturation with the accompanying meiotic divisions. The breakdown of the nuclear envelope during meiosis permits the integration of the proviral form of the retrovirus vector into the genome of the oocyte. When pre-maturation oocytes are used, the injected oocytes are then cultured in vitro under conditions which permit maturation of the oocyte prior to fertilization in vitro.
Conditions for the maturation of oocytes from a number of mammalian species bovine, ovine, porcine, murine, caprine) are well known to the art. In general, the base medium used herein for the in vitro maturation of bovine oocytes, TC-M199 medium, may be used for the in vitro maturation of other mammalian oocytes. TC-M199 medium is supplemented with hormones luteinizing hormone and estradiol) from the appropriate mammalian species.
The amount of time a pre-maturation oocyte must be exposed to maturation medium to permit maturation varies between mammalian species as is known to the art. For example, an exposure of about 24 hours is sufficient to permit maturation of bovine oocytes while porcine oocytes require about 44-48 hours.
Occytes may be matured in vivo and employed in place of oocytes matured in vitro in the practice of the present invention. For example, when porcine oocytes are to be employed in the methods of the present invention, matured pre-fertilization oocytes may be harvested directly from pigs that are induced to superovulate as is known to the art. Briefly, on day or 16 of estrus the female pig(s) is injected with about 1000 units of pregnant mare's serum (PMS; available from Sigma and Calbiochem). Approximately 48 hours later, the pig(s) is injected with about 1000 units of human chorionic gonadotropin) (hCG; Sigma) and 24-48 hours later matured oocytes are collected from oviduct. These in vivo matured pre-fertlization oocytes are then injected with the desired retroviral preparation as described herein. Methods for the superovulation and collection of in vivo matured oocytes at the metaphase 2 stage) oocytes are known for a variety of mammals for superovulation of mice, see Hogan et al. (1994), supra at pp. 130-133; for superovulation of pigs and in vitro fertilzation of pig oocytes see Cheng, W. (1995) Doctoral Dissertation, Cambridge University, Cambridge, United Kingdom].
Retroviral vectors capable of infecting the desired species of non-human animal which can be grown and concentrated to very high titers 1 x 10 cfu/ml) are preferentially employed. The use of high titer virus stocks allows the introduction of a defined number of viral particles into the perivitelline space of each injected oocyte. The perivitelline space of most mammalian oocytes can accommodate about 10 picoliters of injected fluid (those in the art know that the volume that can be injected into the perivitelline space of a mammalian oocyte or zygote varies somewhat between species as the volume of an oocyte is smaller than that of a zygote and thus, oocytes can accommodate somewhat less than can zygotes).
The vector used may contain one or more genes encoding a protein of interest; alternatively, the vector may contain sequences which produce anti-sense RNA sequences or ribozymes. The infectious virus is microinjected into the perivitelline space of oocytes (including pre-maturation oocytes) or one cell stage zygotes. Microinjection into the perivitelline space is much less invasive than the microinjection of nucleic acid into the pronucleus of an embryo. Pronuclear injection requires the mechanical puncture of the plasma membrane of the embryo and results in lower embryo viability. In addition, a higher level of operator skill is required to perform pronuclear injection as compared to perivitelline injection. Visualization of the pronucleus is not required when the virus is injected into the perivitelline space (in contrast to injection into the pronucleus); therefore injection into the perivitelline space obviates the difficulties associated with visualization of pronuclei in species such as cattle, sheep and pigs.
The virus stock may be titered and diluted prior to microinjection into the perivitelline space so that the number of proviruses integrated in the resulting transgenic animal is controlled. The use of a viral stock (or dilution thereof) having a titer of 1 x 10' cfu/ml allows the delivery of a single viral particle per oocyte. The use of pre-maturation oocytes or mature fertilized oocytes as the recipient of the virus minimizes the production of animals which are mosaic for the provirus as the virus integrates into the genome of the oocyte prior to the occurrence of cell cleavage.
In order to deliver, on average, a single infectious particle per oocyte, the micropipets used for the injection are calibrated as follows. Small volumes about 5-10 pl) of the undiluted high titer viral stock a titer of about 1 x 108 cfu/ml) are delivered to the wells of a microtiter plate by pulsing the micromanipulator. The titer of virus delivered per a given number of pulses is determined by diluting the viral stock in each well and determining the titer using a suitable cell line the 208F cell line) as described in Ex. 2. The number of pulses which deliver, on average, a volume of virus stock containing one infectious viral 16particle gives a MOI of 1 when titered on 208F cells) are used for injection of the viral stock into the oocytes.
Prior to microinjection of the titered and diluted (if required) virus stock, the cumulus cell layer is opened to provide access to the perivitelline space. The cumulus cell layer need not be completely removed from the oocyte and indeed for certain species of animals cows, sheep, pigs, mice) a portion of the cumulus cell layer must remain in contact with the oocyte to permit proper development and fertilization post-injection. Injection of viral particles into the perivitelline space allows the vector RNA the viral genome) to enter the cell through the plasma membrane thereby allowing proper reverse transcription of the viral RNA.
IV. Detection of the Retrovirus Following Injection Into Oocytes or Embryos The presence of the retroviral genome in cells oocytes or embryos) infected with pseudotyped retrovirus may be detected using a variety of means. The expression of the gene product(s) encoded by the retrovirus may be detected by detection of mRNA corresponding to the vector-encoded gene products using techniques well known to the art Northern blot, dot blot, in situ hybridization and RT-PCR analysis). Direct detection of the vector-encoded gene product(s) is employed when the gene product is a protein which either has an enzymatic activity P-galactosidase) or when an antibody capable of reacting with the vector-encoded protein is available.
Alternatively, the presence of the integrated viral genome may be detected using Southern blot or PCR analysis. For example, the presence of the LZRNL or LSRNL genomes may be detected following infection of oocytes or embryos using PCR as follows.
Genomic DNA is extracted from the infected oocytes or embryos (the DNA may be extracted from the whole embryo or alternatively various tissues of the embryo may be examined) using techniques well known to the art. The LZRNL and LSRNL viruses contain the neo gene and the following primer pair can be used to amplify a 349-bp segment of the neo gene: upstream primer: 5'-GCATTGCATCAGCCATGATG-3' (SEQ ID NO:1) and downstream primer: 5'-GATGGATTGCACGCAGGTTC-3' (SEQ ID NO:2). The PCR is carried out using well known techniques using a GeneAmp kit according to the manufacturer's instructions (Perkin-Elmer)]. The DNA present in the reaction is denatured by incubation at 94*C for 3 min followed by 40 cycles of 94 0 C for 1 min, 60 0 C for 40 sec and 72 0 C for sec followed by a final extension at 72 0 C for 5 min. The PCR products may be analyzed by 17electrophoresis of 10 to 20% of the total reaction on a 2% agarose gel; the 349-bp product may be visualized by staining of the gel with ethidium bromide and exposure of the stained gel to UV light. If the expected PCR product cannot be detected visually, the DNA can be transferred to a solid support a nylon membrane) and hybridized with a 32 P-labeled neo probe.
Southern blot analysis of genomic DNA extracted from infected oocytes and/or the resulting embryos, offspring and tissues derived therefrom is employed when information concerning the integration of the viral DNA into the host genome is desired. To examine the number of integration sites present in the host genome, the extracted genomic DNA is typically digested with a restriction enzyme which cuts at least once within the vector sequences. If the enzyme chosen cuts twice within the vector sequences, a band of known predictable).size is generated in addition to two fragments of novel length which can be detected using appropriate probes.
EXPERIMENTAL
The following examples serve to illustrate certain preferred embodiments and aspects of the present invention and are not to be construed as limiting the scope thereof.
In the experimental disclosure which follows, the following abbreviations apply: M (molar); mM (millimolar); pM (micromolar); nM (nanomolar); mol (moles); mmol (millimoles); pmol (micromoles); nmol (nanomoles); gm (grams); mg (milligrams); pg (micrograms);pg (picograms); L (liters); ml (milliliters); pl (microliters); cm (centimeters); mm (millimeters); pm (micrometers); nm (nanometers); OC (degrees Centigrade); AMP (adenosine 5'-monophosphate); BSA (bovine serum albumin); cDNA (copy or complimentary DNA); CS (calf serum); DNA (deoxyribonucleic acid); ssDNA (single stranded DNA); dsDNA (double stranded DNA); dNTP (deoxyribonucleotide triphosphate); LH (luteinizing hormone); NIH (Natioal Institues of Health, Besthesda, MD); RNA (ribonucleic acid); PBS (phosphate buffered saline); g (gravity); OD (optical density); HEPES (N-[2-Hydroxyethyl]piperazine-N-[2-ethanesulfonic acid]); HBS (HEPES buffered saline); PBS (phosphate buffered saline); SDS (sodium dodecylsulfate); Tris-HCI (tris[Hydroxymethyl]aminomethane-hydrochloride); Klenow (DNA polymerase I large (Klenow) fragment); rpm (revolutions per minute); EGTA (ethylene glycol-bis(1-aminoethyl ether) N, N, N'-tetraacetic acid); EDTA (ethylenediaminetetracetic acid); bla (-lactamase or ampicillin-resistance gene); ORI (plasmid origin of replication); lacI (lac repressor); X-gal 18- (5-bromo-4-chloro-3-indolyl-P-D-galactoside); ATCC (American Type Culture Collection, Rockville, MD); GIBCO/BRL (GIBCO/BRL, Grand Island, NY); Perkin-Elmer (Perkin- Elmer, Norwalk, CT); and Sigam (Sigma Chemical Company, St. Louis, MO).
EXAMPLE 1 Generation of Cell Lines Stably Expressing the MoMLV gag and pol Proteins The expression of the fusogenic VSV G protein on the surface of cells results in syncytium formation and cell death. Therefore, in order to produce retroviral particles containing the VSV G protein as the membrane-associated protein a three step approach was taken. First, stable cell lines expressing the gag and pol proteins from MoMLV at high levels were generated 293GP cells; Example These stable cell lines were then infected using the desired retroviral vector which is derived from an amphotrophic packaging cell PA317 cells transfected with the desired retroviral vector, Example 2a). The infected stable cell line which expresses the gag and pol proteins produces noninfectious viral particles lacking a membrane-associated protein a envelope protein). Third, these infected cell lines are then transiently transfected with a plasmid capable of directing the high level expression of the VSV G protein (Example 2b). The transiently transfected cells produce VSV G-pseudotyped retroviral vectors which can be collected from the cells over a period of 3 to 4 days before the producing cells die as a result of syncytium formation.
The first step in the production of VSV G-pseudotyped retroviral vectors, the generation of stable cell lines expressing the MoMLV gag and pol proteins is described below.
The human adenovirus 5-transformed embryonal kidney cell line 293 (ATCC CRL 1573)owas cotransfected with the pCMVgag-pol and pFR400 plasmids using a ratio of 10:1 (pCMVgag-pol and pFR400). pCMV gag-pol contains the MoMLV gag and pol genes under the control of the CMV promoter (pCMV gag-pol is available from the ATCC). pFR400 encodes a mutant dihydrofolate reductase which has a reduced affinity for methotrexate [Simonsen et al., Proc. Natl. Acad. Sci. 80:2495 (1983)].
The plasmid DNA was introduced into the 293 cells using calcium phosphate coprecipitation [Graham and Van der Eb, Virol. 52:456 (1973)]. Approximately 5 x 105 293 cells were plated into a 100 mm tissue culture plate the day before the DNA co-precipitate -19was added. A total of 20 gg of plasmid DNA (18 ug pCMV gag-pol and 2 gg pFR400) was added as a calcium-DNA co-precipitate to each 100 mm plate. Stable transformants were selected by growth in DMEM-high glucose medium containing 10% FCS, 0.5 tM methotrexate and 5 gM dipyridimole (selective medium). Colonies which grew in the selective medium were screened for extracellular reverse transcriptase activity [Goff et al., J.
Virol. 38:239 (1981)] and intracellular p30P8 expression. p30 expression was determined by Western blotting using a goat-anti p30 antibody (NCI antiserum 77S000087). A clone which exhibited stable expression of the retroviral genes in the absence of continued methotrexate selection was selected. This clone was named 293GP (293 gag-pol). The 293GP cell line, a derivative of the human Ad-5-transformed embryonal kidney cell line 293, was grown in DMEM-high glucose medium containing 10% FCS. The 293GP cell line is commercially available from Viagen, Inc., San Diego, CA.
EXAMPLE 2 Preparation of Pseudotyped Retroviral Vectors Bearing the G Glycoprotein of VSV In order to produce VSV G protein pseudotyped retrovirus the following steps were taken. First, the 293GP cell line was infected with virus derived from the amphotrophic packaging cell line PA317. The infected cells packaged the retroviral RNA into viral particles which lack a membrane-associated protein (because the 293GP cell line lacks an env gene or other gene encoding a membrane-associated protein). The infected 293GP cells were then transiently transfected with a plasmid encoding the VSV G protein to produce pseudotyped viral particles bearing the VSV G protein.
a) Cell Lines and Plasmids The amphotropic packaging cell line, PA317 (ATCC CRL 9078) was grown in DMEM-high glucose medium containing 10% FCS. The 293GP cell line was grown in DMEM-high glucose medium containing 10% FCS. The titer of the pseudo-typed virus may be determined using either 208F cells [Quade (1979) Virol. 98:461] or NIH/3T3 cells (ATCC CRL 1658); 208F and NIH/3T3 cells are grown in DMEM-high glucose medium containing
CS.
The plasmid pLZRNL [Xu et al. (1989) Virol. 171:331] contains the gene encoding E.
coli P-galactosidase (LacZ) under the transcriptional control of the LTR of the Moloney murine sarcoma virus (MSV) followed by the gene encoding neomycin phosphotransferase (Neo) under the transcriptional control of the Rous sarcoma virus (RSV) promoter. The plasmid pLSRNL contains the gene encoding the hepatitis B surface antigen gene (HBsAg) under the transcriptional control of the MSV LTR followed by the Neo gene under the control of the RSV promoter Patent No. 5,512,421, the disclosure of which is herein incorporated by reference). The plasmid pHCMV-G contains the VSV G gene under the transcriptional control of the human cytomegalovirus intermediate-early promoter [Yee et al.
(1994) Meth. Cell Biol. 43:99].
b) Production and Titering of Pseudotyped LZRNL Virus pLZRNL DNA was transfected into the amphotropic packaging line PA317 to produced LZRNL virus. The resulting LZRNL virus was then used to infect 293GP cells to produce pseudotyped LZRNL virus bearing the VSV G protein (following transient transfection of the infected 293GP cells with a plasmid encoding the VSV G protein). The procedure for producing pseudotyped LZRNL virus was carried out as described [Yee et al.
(1994) Meth. Cell Biol. 43:99].
Briefly, on day 1, approximately 5 x 10 s PA317 cells were placed in a 100 mm tissue culture plate. On the following day (day the PA317 cells were transfected with 20 jig of pLZRNL plasmid DNA (plasmid DNA was purified using CsCl gradients) using the standard calcium phosphate co-precipitation procedure [Graham and Van der Eb (1973) Virol. 52:456].
A range of 10 to 40 gg of plasmid DNA may be used. Because 293GP cells may take more than 24 hours to attach firmly to tissue culture plates, the 293GP cells may be placed in 100 mm plates 48 hours prior to transfection. The transfected PA317 cells provide amphotropic LZRNL virus.
On day 3, approximately 1 x 10 s 293GP cells were placed in a 100 mm tissue culture plate 24 hours prior to the harvest of the amphotropic virus from the transfected PA317 cells.
On day 4, culture medium was harvested from the transfected PA317 cells 48 hours after the application of the pLZRNL DNA. The culture medium was filtered through a 0.45 im filter and polybrene was added to a final concentration of 8 Ig/ml. A stock solution of polybrene was prepared by dissolving 0.4 gm hexadimethrine bromide (polybrene; Sigma) in 100 ml sterile water; the stock solution was stored at 4 0 C. The culture medium containing LZRNL -21 virus (containing polybrene) was used to infect the 293GP cells as follows. The culture medium was removed from the 293GP cells and was replaced with the LZNRL virus containing culture medium. The virus containing medium was allowed to remain on the 293GP cells for 16 hours. Following the 16 hour infection period (on day the medium was removed from the 293GP cells and was replaced with fresh medium containing 400 pg/ml G418 (GIBCO/BRL). The medium was changed every 3 days until G418-resistant colonies appeared two weeks later. Care was taken not to disturb the G418-resistant colonies when the medium was changed as 293GP cells attach rather loosely to tissue culture plates.
The G418-resistant 293 colonies were picked using an automatic pipettor and transferred directly into 24-well plates the colonies were not removed from the plates using trypsin). The G418-resistant 293 colonies (as termed "293GP/LZRNL" cells) were screened for the expression of the LacZ gene in order to identify clones which produce high titers of pseudotyped LZRNL virus. Clones in 24-well plates were transferred to 100 mm tissue culture plates and allowed to grow to confluency. Protein extracts are prepared from the confluent plates by washing the cells once with 10 ml PBS (137 mM NaCl, 2.6 mM KCI, 8.1 mM Na 2
HPO
4 1.5 mM KH 2
PO
4 Two ml of 250 mM Tris-HC1, pH 7.8 was added and the cells were scrapped off the plate using a rubber policeman. The cells were then collected by centrifugation at room temperature and resuspended in 100 pl 250 mM Tris-HC1, pH 7.8.
The cells were subjected to four rapid freeze/thaw cycles followed by centrifugation at room temperature to remove cell debris. The p-galactosidase activity present in the resulting protein extracts was determined as follows. Five microliters of protein extract was mixed with 500 1l P-gal buffer (50 mM Tris-HC1, pH 7.5, 100 mM NaCI, 10 mM MgCl 2 containing 0.75 ONPG (Sigma). The mixtures were incubated at 37 0 C until a yellow color appeared. The reactions were stopped by the addition of 500 pl 10 mM EDTA and the optical density of the reactions was determined at 420 nm.
The 293GP/LZRNL clone which generated the highest amount of P-galactosidase activity was then expanded and used subsequently for the production of pseudotyped LZNRL virus as follows. Approximately 1 x 106 293GP/LZRNL cells were placed into a 100 mm tissue culture plate. Twenty-four hours later, the cells were transfected with 20 gg of pHCMV-G plasmid DNA using calcium phosphate co-precipitation. Six to eight hours after the calcium-DNA precipitate was applied to the cells, the DNA solution was replaced with fresh culture medium (lacking G418). Longer transfection times (overnight) have been found -22to result in the detachment of the majority of the 293GP/LZRNL cells from the plate and are therefore avoided. The transfected 293GP/LZRNL cells produce pseudotyped LZRNL virus.
The pseudotyped LZRNL virus generated from the transfected 293GP/LZRNL cells can be collected at least once a day between 24 and 96 hr after transfection. The highest virus titer was generated approximately 48 to 72 hr after initial pHCMV-G transfection.
While syncytium formation became visible about 48 hr after transfection in the majority of the transfected cells, the cells continued to generate pseudotyped virus for at least an additional 48 hr as long as the cells remained attached to the tissue culture plate. The collected culture medium containing the VSV G-pseudotyped LZRNL virus was pooled, filtered through a 0.45 lim filter and stored at -70 0
C.
The titer of the VSV G-pseudotyped LZRNL virus was then determined as follows. x 10 s rat 208F fibroblasts or NIH 3T3 cells were plated in a 100 mm culture plate. Twentyfours hours after plating, the cells were infected with serial dilutions of the LZRNL viruscontaining culture medium in the presence of 8 pg/ml polybrene. Sixteen hours after infection with virus, the medium was replaced with fresh medium containing 400 gg/ml G418 and selection was continued for 14 days until G418-resistant colonies became visible. Viral titers were typically about 0.5 to 5.0 x 10' colony forming units (cfu)/ml. The titer of the virus stock could be concentrated to a titer of greater than 10 9 cfu/ml as described below.
EXAMPLE 3 Concentration of Pseudotyped Retroviral Vectors The VSV G-pseudotyped LZRNL virus was concentrated to a high titer by two cycles of ultracentrifugation. The frozen culture medium collected as described in Example 2 which contained pseudotyped LZRNL virus was thawed in a 37 0 C water bath and was then transferred to ultraclear centrifuge tubes (14 x 89 mm; Beckman,.Palo Alto, CA) which had been previously sterilized by exposing the tubes to UV light in a laminar flow hood overnight. The virus was sedimented in a SW41 rotor (Beckman) at 50,000 x g (25,000 rpm) at 4*C for 90 min. The culture medium was then removed from the tubes in a laminar flow hood and the tubes were well drained. The virus pellet was resuspended to 0.5 to 1% of the original volume of culture medium in either TNE (50 mM Tris-HCI, pH 7.8; 130 mM NaCl; 1 mM EDTA) or 0.1X Hank's balanced salt solution [IX Hank's balanced salt solution contains 1.3 mM CaCl 2 5 mM KCI, 0.3 mM KH 2
PO
4 0.5 mM MgCl 2 0.4 mM 23- MgSO 4 *7H 2 0, 138 mM NaC1, 4 mM NaHCO 3 0.3 mM NaH 2
PO,
4
H
2 0; 0.1X Hank's is made by mixing 1 parts IX Hank's with 9 parts PBS]. The resuspended virus pellet was incubated overnight at 4 0 C without swirling. The virus pellet could be dispersed with gentle pipetting after the overnight incubation without significant loss of infectious virus. The titer of the virus stock was routinely increase 100- to 300-fold after one round of ultracentrifugation. The efficiency of recovery of infectious virus varied between 30 and 100%.
The virus stock was then subjected to low speed centrifugation in a microfuge for min at 4 0 C to remove any visible cell debris or aggregated virions that were not resuspended under the above conditions (if the virus stock is not to be used for injection into oocytes or embryos, this centrifugation step may be omitted).
The virus stock was then subjected to another round of ultracentrifugation to concentrate the virus stock further. The resuspended virus from the first round of centrifugation was pooled and pelleted by a second round of ultracentrifugation which was performed as described above. Viral titers were increased approximately 2000-fold after the second round of ultracentrifugation (titers of the pseudotyped LZRNL virus were typically greater than or equal to 1 x 109 cfulml after the second round of ultracentrifugation).
The titers of the pre- and post-centrifugation fluids were determined by infection of 208F (NIH 3T3 or Mac-T cells can also be employed) followed by selection of G418resistant colonies as described above in Example 2. The concentrated viral stock was stable did not lose infectivity) when stored at 4 0 C for several weeks.
EXAMPLE 4 Preparation of Pseudotyped Retrovirus For Infection of Oocytes and Embryos The concentrated pseudotyped retrovirus were resuspended in 0.1X HBS (2.5 mM HEPES, pH 7.12, 14 mM NaCI, 75 M Na 2
HPO
4
H
2 0O) and 18 pl aliquots were placed in ml vials (Eppendorf) and stored at -80 0 C until used. The titer of the concentrated vector was determined by diluting 1pl of the concentrated virus 10- 7 or 10--fold with 0.1X HBS. The diluted virus solution was then used to infect 208F and Mac-T cells and viral titers were determined as described in Example 2.
Prior to infection of oocytes or embryos (by microinjection), 1 pl of polybrene ng/gl; the working solution of polybrene was generated by diluting a stock solution having a concentration of 1 mg/ml (in sterile H 2 0) in 0.1 HBS, pH 7.12] was mixed with 4 pl of -24concentrated virus to yield a solution containing 10'-100' cfiiltl and 8 jig/mI polybrene. This solution was loaded into the injection needle (tip having an internal diameter of approximately 2-4 jim) for injection into the perivitelline space of gametes (pre-maturation oocytes, matured oocytes) or one cell stage zygotes (early stage embryo). An Eppcndorf Transjector 5246 was used for all microinjections.
EXAMIPLE Preparation and Microinjection of Gametes and Zygotes Gametes (pre-maturation and pre-fertilization oocytes) and zygotes (fertilized oocytes) were prepared and microinjected with retroviral stocks as described below.
a) Solutions Tyrodes-Lactate with HEPES (TL-HEPES): 114 mM NaCI, 3.2 mM KCl, 2.0 mM NaHCQ 3 0.4 mM Na 2
H
2
PO
4
-H
2 0, 10 mM Na-lactate, 2 mM CaCl 2 -2H 2 O, 0.5 M MgCI 2 *6H 2 0, 10 mM HEPES, 100 IU/ml penicillin, 50 jig/ml phenol red, 1 mg/mI BSA fraction V, 0.2 mM pyruvate and 25 jig/mI gentamycin.
Maturation Medium: TC-199 medium (G[BCO) containing 10% FCS, 0.2 mM pyruvate, .5 jig/ml NTH o-LH (NIH), 25 jig/ml-gentamycin and Ijig/ml estradiol-17P.
Sperm-Tyrodes-Lactate (Sperm-TL): 100 mM NaCI, 3.2 mM KCl, 25 mM NaHCO 3 0.29 mM Na 2
H
2
PO,
4 21.6 mM Na-lactate, 2.1 mM CaCI 2 *2H 2 0, 0.4 MM MgC1 2 -6H 2 0, mM HEPES, 50 jig/mI phenol red, 6 mg/ml BSA fraction V, 1.0 mM pyruvate and gg/mI gentamycin.
Fertilization Medium: 114 mM NaCl, 3.2 ruM KCI, 25 mM NaHCO 3 0.4 mM Na 2
H
2
PO
4
.H
2 0, 10 mM Na-lactate, 2 mM CaCI 2 .2H 2 0, 0.5 MM MgCl 2 -6H 2 0, 100 lU/mi penicillin, 50 jg/mlI phenol red, 6 mg/ml BSA fatty acid free, 0.2 mM pyruvate and 25 pg/mI gentamycin.
PHlE: 1 mM hypotaurine, 2 mM penicillamine and 250 p.M epinephrine.
Embryo Incubation Amino Acids (EIAA): 114 pM NaCl, 3.2 pM KCl, 25 ptM NaHCO 3 1.6 pg/mi L(+)-lactate, 10.7 pg/mI L-glutamine, 300 gg/ml BSA fatty acid free, 0.2 75 pg/ ml pyruvate, 25 jig/mi gentamycin, 10 p1 of 1 OOX MEM amino acids stock (M7145, Sigma) per ml and 20 jil of 5OX BME amino acids stock (B6766, Sigma) per ml.
0.1IX fIBS: 2.5 mM HEPES (pH 7.12), 14 mM NaCI and 75 jiM Na 2
HPO,
4
H
2
O.
25 b) Preparation, Injection, Maturation and Fertilization of Pre- Maturation Oocytes Oocytes were aspirated from small antral follicles on ovaries from dairy cattle obtained from a slaughterhouse. Freshly aspirated oocytes at the germinal vesicle (GV) stage, meiosis arrested, with the cumulus mass attached were selected pre-maturation oocytes).
The oocytes were then washed twice in freshly prepared TL-HEPES and transferred into a 100 il drop of TL-HEPES for microinjection.
Concentrated retroviral particles (prepared as described in Example 3) were resuspended in 0.1X HBS, mixed with polybrene and loaded into the injection needle as described in Example 4. Approximately 10 pl of the virus solution was then injected into the perivitelline space of pre-maturation oocytes.
Following injection, the pre-maturation oocytes were washed twice in fresh TL- HEPES and transferred into maturation medium (10 oocytes in 50 pl). The pre-maturation oocytes were then incubated in Maturation Medium for 24 hours at 37 0 C which permits the oocytes to mature to the metaphase II stage. The matured oocytes were then washed twice in Sperm-TL and 10 oocytes were then transferred into 44 pl of Fertilization Medium. The mature oocytes (10 oocytes/44 il Fertilization Medium) were then fertilized by the addition of 2 gl of sperm at a concentration of 2.5 x 107/ml, 2 pil of PHE and 2 p. of heparin (fertilization mixture). Sperm was prepared by discontinuous percoll gradient separation of frozen-thawed semen as described [Kim et al. (1993) Mol. Reprod. Develop. 35:105].
Briefly, percoll gradients were formed by placing 2 ml of each of 90% and 45% percoll in a ml conical tube. Frozen-thawed semen was layered on top of the gradient and the tubes were centrifuged for 10 minutes at 700xg. Motile sperm were collected from the bottom of the tube.
The oocytes were incubated for 16 to 24 hours at 37 0 C in the fertilization mixture.
Following fertilization, the cumulus cells were removed by vortexing the cells (one cell stage zygotes, Pronucleus Stage) for 3 minutes to produce "nude" oocytes. The nude oocytes were then washed twice in embryo culture medium (EIAA) and 20 to 25 zygotes were then cultured in 50 pl drop of EIAA (without serum until Day 4 at which time the zygotes were placed in EIAA containing 10% serum) until the desired developmental stage was reached: approximately 48 hours or Day 2 (Day 0 is the day when the matured oocytes are co-cultured with sperm) for morula stage (8 cell stage) or Day 6-7 for blastocyst stage. Embryos at the morula stage were analyzed for expression of P-galactosidase as described in Example 6.
26- Embryos derived from injected pre-maturation oocytes were also analyzed for P-galactosidase expression at the 2 cell, 4 cell, and blastocyst stage and all developmental stages examined were positive.
c) Preparation, Injection and Fertilization of Pre-Fertilization Oocytes Pre-maturation oocytes were harvested, washed twice with TL-HEPES as described above. The oocytes were then cultured in Maturation Medium (10 oocytes per 50 p1 medium) for 16 to 20 hours to produce pre-fertilization oocytes (Metaphase II Stage). The pre-fertilization or matured oocytes were then vortexed for 3 minutes to remove the cumulus cells to produce nude oocytes. The nude oocytes were washed twice in TL-HEPES and then transferred into a 100 pl drop of TL-HEPES for microinjection. Microinjection was conducted as described above.
Following microinjection, the pre-fertilization oocytes were washed twice with TL- HEPES and then placed in Maturation Medium until fertilization. Fertilization was conducted as described above. Following fertilization, the zygotes were then washed twice in EIAA and to 25 zygotes were then cultured per 50 pl drop of EIAA until the desired developmental stage was reached. The embryos were then examined for P-galactosidase expression (Ex. 6) or transferred to recipient cows (Ex. 7).
d) Preparation and Injection of One-Cell Stage Zygotes Matured oocytes (Metaphase II stage) were generated as described above. The matured oocytes were then co-cultured in the presence of sperm for 16 to 20 hours as described above to generate zygotes at the pronucleus stage. Zygotes at the pronucleus stage were vortexed for 3 minutes to remove the cumulus cell layer prior to microinjection.
Microinjection of retrovirus was conducted as described above. Following microinjection, the zygotes were washed four times in EIAA and then placed in an EIAA culture drop zygotes per 50 pl drop of EIAA). The zygotes were cultured in EIAA (20 to 25 zygote per pt drop of EIAA) until the desired developmental stage was reached. The embryos were then examined for P-galactosidase expression (Ex. 6) or transferred to recipient cows (Ex. 7).
-27 EXAMPLE 6 Injection of Pseudotyped Retrovirus Into the Perivitelline Space of Maturing Bovine Oocytes Results in the Efficient Transfer of Vector Sequences Oocytes and one-cell zygotes which had been microinjected with pseudotyped LZRNL virus and cultured in vitro were examined for expression of vector sequences by staining for p-galactosidase activity when the embryos had reached the morula stage. P-galactosidase activity was examined as follows. Embryos were washed twice in PBS then fixed in glutaraldehyde in PBS containing 2mM MgCl 2 for 40 min. at 4 *C The fixed embryos were then washed three times with PBS containing 2mM MgCI, and then incubated at 37 0
C
overnight in X-gal solution (20mM K3Fe(CN),, 20mM K 4 Fe(CN)6.H 2 0, 2 mM MgCl 2 and 1 mg/ml X-gal). The presence of a blue precipitate indicates expression of P-galactosidase activity. The results are shown in Table 1 below.
TABLE 1 Stage at Injection Stage at Analysis Positive For P-galactosidase Expression Pre-Fertilization Oocyte Morula 47 (80/172)" (injected 20-24 hrs after exposure to Maturation Medium) Pronuclei Stage (injected Morula 25 (20/80) 18-20 hrs after exposure to sperm) One-Cell Zygote Morula 25 (20/80) Number positive/number injected.
From the results shown in Table 1, it is clear that infection of pre-fertilization oocytes and zygotes using the methods of the present invention results in the transfer and expression of retrovirally encoded nucleic acid. While not limiting the present invention to any particular theory, it is currently believed that only half of the daughter cells from an initial founder cell infected with a retrovirus will contain the provirus because the retroviral provirus integrates into post-replication host DNA [Hajihosseini et al. (1993) EMBO J. 12:4969].
Therefore, the finding that 47% of the injected pre-fertilization oocytes are positive for P- 28 galactosidase expression suggests that 100% of these injected oocytes were infected with the recombinant retrovirus. Therefore, the methods of the present invention provide an efficiency of generating transgenic embryos which is superior to existing methods.
EXAMPLE 7 Generation of Transgenic Cows Containing Integrated Retroviral Nucleic Acid Sequences Embryos derived from infected pre-fertilization oocytes and early zygotes were transferred into recipient cows which were allowed to progress to term as described below.
a) Treatment of Embryos Derived From Infected Oocytes and Zygotes Pre-fertilization oocytes (infected about 17 hours after exposure to Maturation Medium) and early stage zygotes (5 8 cell stage) were prepared and infected as described in Example 5 with the exceptions that 1) the VSV-G-pseudotyped virus used was the LSRNL virus which was prepared as described for the LZRNL virus in Ex. 2 and 2) at day 4 postfertilization, embryos derived from injected pre-fertilization oocytes and zygotes were placed in freshly prepared EIAA medium containing 10% FCS and allowed to develop in vitro until transfer into recipient cows. Embryos at Day 7 were transferred into recipient females which were prepared as described below.
b) Preparation of Recipient Cows and Embryo Transfer Recipients cows were synchronized by injecting 100 pg of gonadotropin-releasing hormone (GnRH; Sanofi Winthrop Pharmaceutical Inc., New York, NY) (Day Seven days later, the recipients were injected with 25 mg of PGF2a (Upjohn Co., Kalamazoo, MI).
Thirty to 48 hours after injection of PGF2a, a second injection of 100 pg of GnRH was given. Ovulation occurs about 24-32 hours post injection. Seven days after ovulation occurred, embryos derived from infected oocytes and zygotes (Day 7 embryos) were then transferred nonsurgically to the uteri the recipient cows. Two embryos were transferred into each recipient (it is expected that only one calf will be born from the transfer of two embryos into a single recipient).
-29 A total of 20 embryos were transferred into recipients on three separate days. In the first transfer 8 embryos derived from infected pre-fertilization oocytes were transferred into 4 recipients; four calves were born to these recipients and all four were found to be positive for the presence of vector proviral DNA 100% were transgenic). In the second transfer 8 embryos derived from pre-fertilization oocytes were transferred into 4 recipients; 2 calves were born to these recipients and one of these animals was found to be transgenic (in the second transfer, one pregnancy was lost in the first month and another pregnancy comprising twins was lost in the eighth month; neither embryo from the 8 month pregnancy was transgenic). In the third transfer 4 embryos derived from infected zygotes (infected at the 4-8 cell stage) were transferred into 2 recipients; 3 calves were born to these recipients and none were transgenic.
The nine calves appeared healthy at birth and continue to appear healthy at the age of 6 months. Following the birth of offspring derived from the injected oocytes and zygotes, the offspring were examined by Southern blot and PCR analyses to determine whether they contained the retroviral transgenes and whether they exhibited somatic cell mosaicism. Skin tissue and white blood cells (buffy coat) was collected from the calves. Genomic DNA was extracted using standard techniques. Briefly, the tissue samples were digested with 50 gg/ml proteinase K (GIBCO) at 55C. The samples were then extracted sequentially twice with an equal volume of phenol, once with phenol:chloroform and once with chloroform. The DNA present in the aqueous layer was then precipitated by the addition of 2 volumes of isopropanol. The DNA was collected by centrifugation and the DNA pellet was resuspended in TE buffer (10mM Tris-Cl, 1 mM EDTA, pH 8.0) and the concentration was determined spectrophotometrically. The DNA was then analyzed by Southern blotting and PCR analysis.
The results are shown in Figures 2 and 3.
Figure 2 shows an autoradiography of a Southern blot of genomic DNA isolated from the skin (Fig. 2A) and blood (Fig. 2B) of the six calves derived from either pre-fertilization oocytes infected with VSV G-pseudotyped LSRNL virus at about 17 hours after exposure to Maturation Medium (calves numbered 17, 18, 20 and 21) or one cell zygotes infected at about 12 hrs post-fertilization (calves numbered 15 and 16). The calf DNA was digested with HindIII which cuts the pLSRNL vector twice to generate a 1.6 kb fragment (Fig. 2C).
HindIII-digested DNA from the blood (lane labelled *12 derived from a randon, nontransgenic calf), ovary and semen of nontransgenic cows (derived random adult females and males) were also included. Lanes labeled "3989 M and F" represent DNA derived from two late term embryos that were born one month prematurely (these calves were generated from injected fertilized eggs and both are nontransgenic). Lanes labelled "LSRNL pDNA" contain HindIII-digested pLSRNL plasmid DNA and provide controls for the quantitiation of the copy number of the integrated proviruses in the offspring (DNA equivalent to 5, 10 or copies of LSRNL were applied in these lanes).
Approximately 10 gg of the HindIII-digested DNAs were electrophoresed on 0.8% agarose gels, and blotted onto a nylon membrane. The membrane was hybridized with a 2plabelled probe which hybridizes to the HBsAg gene present in the pLZRNL vector (Fig. 2C).
The HBsAG probe was generated by PCR amplification of pLSRNL plasmid DNA using the upstream primer S-1 [5'-GGCTATCGCTGGATGTGTCT-3' (SEQ ID NO:3)] and the downstream primer S-3 [5'-ACTGAACAAATGGCACTAGT-3' (SEQ ID The PCRgenerated probe (334 bp) was labeled using a Rediprime kit (Amersham, Arlington Heights, IL) according to the manufactuer's instructions. The autoradiographs shown in Fig. 2 were generated by exposure of the blots to X-ray film for 3 weeks at -80 0
C.
The results shown in Figure 2 demonstrates that calves 16, 17, 18, 20 and 21 contained retroviral vector DNA in both the skin (Fig. 2A) and blood (Fig. 2B). As blood cells (buffy coat) are derived from the mesoderm and skin cells are derived from the ectoderm, these results show that the transgenic animals do not display somatic cell mosaicism. Southern blotting analysis has shown that the majority 7/9) of the transgenic calves contain a single copy of the proviral sequence; a few 2/9) animals appear to contain two copies of the integrated proviral sequence. These results further demonstrate that retroviral infection of both pre-fertilization oocytes and early stage zygotes was successful in integrating the viral sequences into the genome of the resulting transgenic animals.
In order to confirm the presence of integrated retroviral sequences in the genome of the transgenic animals' somatic cells, PCR analysis (Fig. 3) was performed using genomic DNA isolated from the five transgenic calves which were determined by Southern blot analysis to be transgenic for the retroviral sequences. Figure 3 shows the results of the PCR analysis following amplification of two different regions the neo gene and the HBsAg gene) of the LZRNL retroviral genome which was injected into the oocytes. Genomic DNA from the skin and blood of each of the five transgenic calves was amplified using the upstream and downstream primers (SEQ ID NOS:1 and 2 and NOS:3 and 4; described supra) for the neo (Fig. 3A) and HBsAg (Fig. 3B) genes, respectively. The. PCRs were -31 conducted using the following thermocycling conditions: 94 0 C 4 min); [94 0 C (2 min); 50 0
C
(2 min); 72 0 C (2 min)] 72 0 C (10 min). Amplification yielded the expected size of amplified sequence with the neo (349 bp) and HBsAg (334 bp) primers in both the blood and skin of each of the five transgenic calves. Genomic DNA isolated from the blood of nontransgenic calves as well as from semen and ovary of non-transgenic cattle were used as negative controls in the PCRs. pLSRNL DNA was used as the positive control.
These data demonstrate that the infection of pre-fertilization oocytes results in the efficient transfer of retroviral vector DNA (100% or 4 transgenic calves/4 calves born from embryos derived from infected pre-fertilization oocytes). In addition to providing a means for efficiently generating transgenic animals. The methods of the present invention provide a means for generating transgenic animals which do not display somatic cell mosaicism.
Further, these methods permit the production of transgenic animals which contain a single copy of the transgene.
In order to confirm germ line transmission of the integrated viral sequences, the transgenic offspring are bred with non-transgenic cattle and the presence of the viral sequences the transgene) is determined using Southern blot analysis or PCR amplification as described above. Animals which are heterozygous or homozygous for the transgene are produced using methods well known to the art interbreeding of animals heterozygous for the transgene).
From the above it is clear that the invention provides improved methods and compositions for the production of transgenic non-human animals. The methods of the present invention provide for the production of transgenic non-human animals with improved efficiency and a reduced incidence of generating animals which are mosaic for the presence of the transgene.
All publications and patents mentioned in the above specification are herein incorporated by reference. Various modifications and variations of the described method and system of the invention will be apparent to those skilled in the art without departing from the scope and spirit of the invention. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention which are obvious to those skilled in molecular biology or related fields are intended to be within the scope of the following claims.
-32- SEQUENCE LISTING GENERAL INFORMATION: APPLICANT: Bremel, Robert D.
Chan, Anthony W.S.
Burns, Jane C.
(ii) TITLE OF INVENTION: Methods For Creating Transgenic Animals (iii) NUMBER OF SEQUENCES: (iv) CORRESPONDENCE ADDRESS: ADDRESSEE: Medlen Carroll, LLP STREET: 220 Montgomery street, Suite 2200 CITY: San Francisco STATE: California COUNTRY: United States of America ZIP: 94104 COMPUTER READABLE FORM: MEDIUM TYPE: Floppy disk COMPUTER: IBM PC compatible OPERATING SYSTEM: PC-DOS/MS-DOS SOFTWARE: Patentln Release Version #1.30 (vi) CURRENT APPLICATION DATA: APPLICATION NUMBER: US FILING DATE:
CLASSIFICATION:
(viii) ATTORNEY/AGENT INFORMATION: NAME: Ingolia, Diane E.
REGISTRATION NUMBER: 40,027 REFERENCE/DOCKET NUMBER: WARF-02184 (ix) TELECOMMUNICATION INFORMATION: TELEPHONE: (415) 705-8410 TELEFAX: (415) 397-8338 INFORMATION FOR SEQ ID NO:l: SEQUENCE CHARACTERISTICS: LENGTH: 20 base pairs TYPE: nucleic acid STRANDEDNESS: single TOPOLOGY: linear (ii) MOLECULE TYPE: other nucleic acid DESCRIPTION: /desc "DNA" (xi) SEQUENCE DESCRIPTION: SEQ ID NO:l: GCATTGCATC AGCCATGATG INFORMATION FOR SEQ ID NO:2: SEQUENCE CHARACTERISTICS: LENGTH: 20 base pairs TYPE: nucleic acid STRANDEDNESS: single TOPOLOGY: linear (ii) MOLECULE TYPE: other nucleic acid DESCRIPTION: /desc "DNA" (xi) SEQUENCE DESCRIPTION: SEQ ID NO:2: GATGGATTGC ACGCAGGTTC -33- INFORMATION FOR SEQ ID NO:3: SEQUENCE CHARACTERISTICS: LENGTH: 20 base pairs TYPE: nucleic acid STRANDEDNESS: single TOPOLOGY: linear (ii) MOLECULE TYPE: other nucleic acid DESCRIPTION: /desc "DNA" (xi) SEQUENCE DESCRIPTION: SEQ ID NO: 3: GGCTATCGCT GGATGTGTCT INFORMATION FOR SEQ ID NO:4: SEQUENCE CHARACTERISTICS: LENGTH: 20 base pairs TYPE: nucleic acid STRANDEDNESS: single TOPOLOGY: linear (ii) MOLECULE TYPE: other nucleic acid DESCRIPTION: /desc HDNA" (xi) SEQUENCE DESCRIPTION: SEQ ID NO:4: ACTGAACAAA TGGCACTAGT INFORMATION FOR SEQ ID Wi SEQUENCE CHARACTERISTICS: LENGTH: 1S90 base pairs TYPE: nucleic acid STRANDEDNESS: double TOPOLOGY: linear (ii) MOLECULE TYPE: other nucleic acid DESCRIPTION: /desc ="DNA" (ix) FEATURE: NAME/KEY: CDS LOCATION: 1S87 (xi) SEQUENCE DESCRIPTION: SEQ ID 1(0:5: ATG GAT Met Asp
I
CTC TTT CCC ATT TTG GTC Leu Phe Pro le Leu Val GTG GTG Val Val 10 CCG GAT Pro Asp CTC ATG ACA GAT Leu Met Thr Asp ACT GTC Thr Val TTA GGG AAG Leu. Gly Lys AGA CCA GTT Arg Pro Val CAA TTC GAT Gln Phe Asp CAA ATT GTC TTC Gin Ile Val Phe GTG GGT GAC TCT CGG CAT TGC Val Gly Asp Ser Arg His Cys 40 GGA AGC AGA TCC CAG ACC ATA Gly Ser Arg Ser Gln Thr Ile 55 CAG AAT GAA CTG GAG TG Gln Asn Glu Leu Glu Trp CCA CAG TCA TCA GAA ATG Pro Gin Ser Ser Glu Met CTG ACT GGG AAA GCT CCC Leu Thr Gly Lys Ala Pro GOG ATC ACG Gly Ile Thr CCC TCT AAA TCA GAT OGA TTT ATC TGC CAT Pro Ser Lys Ser Asp Gly Phe Ile Cys His 75 GCC GCA Ala Ala s0 TAC ATC Tyr Ile TGG GTG ACA ACA TGT GAT TTC AGG TGG TAT GOG CCG AAA Trp Val Thr Thr Cys Asp Phe Arg Trp Tyr Gly Pro Lys 90 34 ACT CAT TCA ATA CAT CAT Thr His Ser Ile His His 100 CTG AGA CCG ACA Leu Arg Pro Thr 105 ACA TCA GAC TOT GAG ACA Thr Ser Asp Cys Glu Thr 110 CAA AGO Gin Arg 115 TCC TGC Ser Cys GTG ACT Val Thr GAC CCA TAT AAA GAT GGG AGC TTA Tyr Lys GOT TAT Gly Tyr CCC CAC Pro His 150 CTA TTT Gly Ser Leu 120 ACA OTC ACA Thr Val Thr ATC AAT CT GOA Ile Asn Leu Gly 125 GAT TCT GAG GCA Asp Ser Olu Ala TTC CCC Phe Pro ATG TTG Met Leu 140 Trp Ile Asp Pro Leu Phe Pro 165 OAT ACA GTC CAC AAT Asp Thr Val His Asn 180 GAC ATC TGT GCC CAG Asp Ile Cys Ala Gln 195 CCC TCA OAA GOA GCA Pro Ser GIu Gly Ala 210 TAT CAT CCA AAT ATG Tyr His Pro Asn Met 225 OAA CAA AAG 000 TTO Olu Gin Lys Gly Leu 245 GTG GAG CAA TCC ATC Val Glu Gin Ser Ile 260 TGT OTT GCA GG ACT Cys Val Ala Gly Thr 275 AGA ACT TTG ACG TOG Arg Thr Leu Thr Trp 290 CAG AAC ACC TOG GAC Gin Asn Thr Trp Asp 305 GAC TTG AC TAT CTG Asp Leu Ser Tyr Leu 325 ACC OTC ATA AAC GGA Thr Val Ile Asn Gly 340 TCA TCG Ser Ser TCT TTC Ser Phe TTO OT Leu Val 215 OTT GGG Val Gly GOA OGA Oly Oly OTG TOG Val Trp 185 AAA AAT Lys Asa 200 AGT GAC Ser Asp GTG GAT Val Asp 155 GAA TGC Glu Cys 170 ATC CCC Ile Pro ATC AAO Ile Lys AGA TTT Arg Phe TAT AGA Tyr Arg ACC AAT Thr Asn CCG GGG TCA ACT OTT TGC Pro Oly Ser Thr Val Cys 230 235 AGA TTC ACA AAT OGA GAG Arg Phe Thr Asn Oly Glu 250 CGA GAO AAG AAG ATA AGT Arg Olu Lys Lys Ile Ser 265 GAA ATC CGA 0CC ACA CTA Glu Ile Arg Ala Thr Leu 280 GAG ACT CAA AGA ATO CTA Giu Tbr Gln Arg Met Leu 295 AAA OTT TCC AGO AAA GAA Lys Val Ser Arg Lys Olu 310 315 TCA CCA AGO GCT CCA 000 Ser Pro Arg Ala Pro Oly 330 ACC CTO CAT TCO OCT CAT Thr Leu His Ser Ala His 345 175 AAG AOT CAA AAG ACT Lys Ser Gin Lys Thr 190 ATG ACC GCA TCT TAC Met Thr Ala Ser Tyr 205 GCC TTC CAC AOT OCA Ala Phe His Ser Ala 220 ATA ATG GAC TTT TOC Ile Met Asp Phe Cys 240 TOG ATO GOT CTC AAT Trp Met Gly Leu Asn 255 GCC ATC TTC CCA AAT Ala Ile Phe Pro Asn 270 OAA TCA GAA GGG OCA Olu Ser Giu Oly Ala 285 OAT TAC TCT TTO TOT Asp Tyr Ser Leu Cys 300 CCT CTC AGT CCG CTT Pro Leu Ser Pro Leu 320 AAA GGC ATG GCC TAT Lys Gly Met Ala Tyr 335 OCT AAA TAC ATT AGA Ala Lys Tyr Ile Arg 350 480 528 576 624 672 720 768 816 864 912 960 1008 1056 1104 ACC TO ATT OAT TAT GOA OAA ATM AAG OAA ATT AAA GOT GOA COT OGA Thr Trp Ile Asp Tyr Oly Olu Met Lys Oiu Ile Lys Oly Oly Arg Gly 355 360 365 GAA TAT Glu Tyr 370 GGA CCG Gly Pro 385 TTr AAA Pile Lys CTG CAT Leu His GAC GCG Asp Ala ACA GGT Tilr Gly 450 AAT TGG Asn Trp 465 GTT GTG Val Val TGG AGA Trp Arg TCC CGA Ser Arg AGA TAA Arg TCC AAG GCT Ser Lys Ala TTC AAA ATT Phe Lys Ile TTC CCT CTT Pile Pro Leu 405 GAA CTA GAT Giu Leu Asp 420 AAA AGC GTT Lys Ser Val 435 GTA TCC AA Val Ser Lys AGA GAG AGT Arg Giu Ser ACA TTT CTG Thr Phe Leu 485 CCC AGA AAG Pro Arg Lys 500 CTA AAC CAT Leu Asn His 515 CCT GAG CTC Pro Giu Leu 375 GGA CCG ARAT Giy Pro Asn 390 TAT TTG ATC Tyr Leu Ile GAG OCT GCT Giu Ala Ala CTT CCA GAA Leu Pro Glu 440 ARC CCT ATC Asn Pro Ile 455 GTA ATG GCA Val Met Ala 470 GCG ATC AAG Ala Ile Lys AAA AGA ATC Lys Arg Ile TTT GAG ATG Phe Giu Met 520 CTC TGG Leu Trp GGA CTC Gly Leu GGA GCR Gly Ala 410 CCC ATT Pro Ile 425 GAT GAR Asp Giu GAG TTG Giu Leu ATA GTC Ile Vai ACG GTC Thr Vai 490 GTC AGA Val Arg 505 AGA GGC Arg Giy TCC CR0 Ser Gin 380 CTG CRC Leu His 395 GGC ATA Gly Ile CAT CRC Asp His GAG ATA Giu Ile ATT CAA Ile Gin 460 GGA ATT Giy Ile 475 COG GTG Arg Val CAA GA Gin Giu TTT CCT Pile Pro TOG TTC Trp Pile ACA GG Thr Giy ATT GAC Ile Asp CCR CAA Pro Gin 430 TTC TTC Phe Phe 445 OGA TGG Gly Trp GTT CTA Vai Leu CTT ART Leu An GTA GAT Vai Asp 510 GAA TAT Giu Tyr 525 GAT TTT Asp Pile AAAR ACC Lys Thr 400 OAR CAT Giu Asp 415 ATO CCT Met Pro GGR CAC Gly Asp TTC TCR Phe Ser CTC ATC Leu Ile 480 TOT CTC Cys Leu 495 OTT GAR Vai Giu GTT ARG Vai Lys 1152 1200 1248 1296 1344 1392 1440 1488 1536 1584 1590 INFORMATION FOR SEQ ID NO:6: Wi SEQUENCE CHARACTERISTICS: LENGTH: 529 amino acids TYPE: amino acid TOPOLOGY: linear (ii) MOLECULE TYPE: protein (xi) SEQUENCE DESCRIPTION: SEQ ID NO:6: Met Asp Leu Pile Pro Ile Leu Vai Vai Vai Leu Met Thr Asp Thr Vai 1 5 10 Leu Gly Lys Pile Gin Ile Val Pile Pro Asp Gin Ann Giu Leu Giu Trp 25 Arg Pro Val Val Gly Asp Ser Arg His Cys Pro Gin Ser Ser Giu Met 40 4S Gin Pile Asp Giy Ser Arg Ser Gin Thr Ile Leu Thr Oly Lys Ala Pro 55 Val Gly Ile Tilr Pro Ser Lys Ser Asp Gly Pile Ile Cys His Ala Ala 70 75 36 Lys Trp Val Thr Thr Cys Asp Phe Arg Trp Tyr Gly Pro Lys Tyr Ile 90 Thr His Ser Ile His 100 Ala Pro Val 145 Trp Asp Asp Pro Tyr 225 Glu Val Cys Arg Gin 305 Asp Thr Thr Glu Gly 385 Phe Leu Leu Gin Arg 115 Glu Ser Cys 130 Gin Val Thr Ile Asp Pro Thr Val His 180 Ile Cys Ala 195 Ser Giu Gly 210 His Pro Asn Gin Lys Gly Glu Gin ser 260 Val Ala Gly 275 Thr Leu Thr 290 Asn Thr Trp Leu Ser Tyr Val lie Asn 340 Trp Ile Asp 355 Tyr Ser Lys 370 Pro Phe Lys Lys Phe Pro His Glu Leu 420 Tyr His Leu Arg Pro 105 Lys Asp Gly Ser 120 Tyr Ala Thr Val 135 His His'Val Gly 150 Phe Pro Gly Gly I Ser Ser Val Trp 185 Ser Pie Lye Asn 200 Leu Val Ser Asp 215 Pro Gly Ser Thr 230 Arg Phe Thr Asn Arg Giu Lye Lys 265 Glu Ile Arg Ala 280 Glu Thr Gin Arg 295 Lys Val Ser Arg 310 Ser Pro Arg Ala Thr Leu His Ser 345 Gly Giu Met Lys 360 Pro Glu Leu Leu 375 Gly Pro Asn Gly 390 Tyr Leu Ile Gly DGlu Ala Ala Pro 425 Thr Leu rhr Val Glu 170 Ile Ile Rrg Val Gly 250 Ile Thr Met Lys Pro 330 Ala Glu Trp Leu Ala 410 Ile Thr Ser Asp Cys Glu Thr 110 Ile Asn Leu Gly Phe Pro 125 Asp Ser Glu Ala Met Leu 140 Asp Asp Tyr Arg Gly His 155 160 Cys Ser Thr Asn Phe Cys 175 Pro Lye Ser Gin Lye Thr 190 Lye Met Thr Ala Ser Tyr 205 Phe Ala Pie His Ser Ala 220 Cys Ile Met Asp Pie Cys 235 240 Glu Trp Met Gly Leu Asn 255 Ser Ala Ile Pie Pro Asn 270 Leu Giu Ser Glu Gly Ala 285 Leu Asp Tyr Ser Leu Cys 300 Glu Pro Leu Ser Pro Leu 315 320 Gly Lys Giy Met Ala Tyr 335 His Ala Lye Tyr Ile Arg 350 Ile Lys Gly Gly Arg Gly 365 SSer Gin Trp Pie Asp Phe 380 Leu His Thr Giy Lye Thr 395 400 Gly Ile Ile Asp Glu Asp 415 Asp His Pro Gin Met Pro 430 Asp Ala Lye 435 Ser Val Leu Pro Gu Asp Glu Giu Ile Pie Phe Gly Asp 440 445 37- Gly Val Ser Lys Asn Pro Ile Giu Leu Ile Gin Giy Trp Phe Ser 450 455 460 Trp, Arg Giu Ser Val Met Ala Ile Val Gly Ile Val Leu Leu Ile 470 475 480 Val Thr Phe Leu Ala Ile Lys Thr Val. Arg Vai Leu Asn Cys Leu 485 490 495 Arg Pro Arg Lys Lys Arg Ile Val Arg Gin Giu Vai Asp Val Glu S00 505 510 Arg Leu Asn His Phe Giu Met Arg Giy Phe Pro Giu Tyr Vai Lys 515 520 525 INFORMATION FOR SEQ ID NO:7: Wi SEQUENCE CHARACTERISTICS: LENGTH: 1590 base pairs TYPE: nucieic acid STRANDEDNESS: double TOPOLOGY: iinear (ii) MOLECULE TYPE: other nucleic acid DESCRIPTION: /desc "IDNA.
(ix) FEATURE: NAME/KEY: CUB LOCATION: i. .1587 (xi) SEQUENCE DESCRIPTION: SEQ ID NO:7: ATO OAT CTC TTT CCC ATT TTG GTC OTG GTO CTC Met Asp Leu Phe Pro 1 5 TTA 000 AAO TI'T CAA Leu. Gly Lys Phe Gin AGA CCA OTT GTG GOT Arg Pro Vai Val Gly CAA TTC OAT GGA AOC Gin Phe Asp Gly Ser s0 O'TG GGG ATC ACO CCC Vai Giy Ile Thr Pro AAA TOG GTG ACA ACA Lys Trp, Val Thr Thr ACT CAT TCA ATA CAT Thr His Ser le His 100 OCT CTC CAA AGG TAT Ala Leu Gin Arg Tyr 115 CCA GAA TCC TGC GOT Pro Giu Ser Cys Gly 130 Ile Leu Vai Val Vai Leu ATG ACA Met Thr 10 ATT GTC TTC CCO GAT CAG AAT GAA Ile Val Phe Pro Asp Gin Asn Oiu 25 GAC TCT COG CAT TGC CCA CAG TCA Asp Ser Arg His Cys Pro Gin Ser 40 AGA TCC CAG ACC ATA CTG ACT 000 Arg Ser Gin Thr Ile Leu Thr Oly 55 TCT AAA TCA OAT OGA TTT ATC TGC Ser Lys Ser Asp Gly Phe Ile Cys 70 TOT OAT TTC AGO TOO TAT 000G CCG Cys Asp Phe Arg Trp Tyr Oly Pro 90 CAT CTO AGA CCO ACA ACA TCA GAC His Leu, Arg Pro Thr Thr Ser Asp 105 AAA OAT 000 AOC TTA ATC AAT CT? Lys Asp Giy Ser Leu Ile RAn Leu.
120 125 TAT OCA ACA GTC ACA OAT TCT GAG Tyr Ala Thr Vai Thr Asp Ser Olu 135 140 OAT ACT Asp Thr CTO GAO Leu Olu TCA GAA Ser Olu AAA OCT Lys Ala CAT 0CC His Ala AAA TAC Lys Tyr TOT GAO Cys Olu 110 GGA TTC Gly Pkie OCA ATG TTG Ala Met Leu -38 GTC CAA GTG ACT CCC CAC CAC GTT 000 GTO GAT GAT TAT AGA GGT CAC Val Gin Vai Thr Pro His His Val Gly Val Asp Asp Tyr Arg Giy His 145 150 155 160 480 TGG ATC GAC CCA Trp Ile Asp Pro OAT ACA GTC CAC Asp Thr Val His IS0 GAC ATC TOT 0CC Asp Ile Cys Ala 195 CCC TCA GAA GGA Pro Ser Glu Giy 210 TAT CAT CCA AAT Tyr His Pro Asn 225 GAA CAA AAO 000 Oiu Gin Lys Gly GTO GAG CAA TCC Val Oiu Gin Ser 260 TOT OTT OCA 000 Cys Val Ala Oly 275 AGA ACT TTG ACO Arg Thr Leu Thr 290 CAG AAC ACC TOO Gin Asn Thr Trp 305 GAC TTO AGC TAT Asp Leu Ser Tyr ACC GTC ATA AAC Thr Val Ile Asn 340 CTA TTT CCA GGA OGA GAA TGC TCC ACC AAT TTT Leu Phe Pro Oly Gly Giu Cys Ser Thr Asa Phe 165 170 175 AAT TCA TCO OTO TOG ATC CCC AAG AGT CAA AAG Asn Ser Ser Val Trp Ile Pro Lys Ser Gin Lys 185 190 CAG TCT TTC AAA AAT ATC AAO ATO ACC GCA TCT Gin Ser Phe Lys As Ile Lys Met Thr Ala Ser 200 205 GCA TTO OTO AOT GAC AGA TTT 0CC TTC CAC AOT Ala Leu Val Ser Asp Arg Phe Ala Phe His Ser 215 220 ATG CCO 000 TCA ACT OTT TGC ATA ATO. GAC TTT Met Pro Gly Ser Thr Val Cys Ile Met Asp Phe 230 235 TTG AGA TTC ACA AAT GGA GAG TOO ATO GOT CTC Leu Arg Phe Thr Asn Gly Oiu Trp Met Oly Leu 245 250 255 ATC CGA GAG AAG AAG ATA AOT 0CC ATC TTC CCA Ile Arg Olu Lys Lys Ile Ser Ala Ile Phe Pro 265 270 ACT GAA ATC COA 0CC ACA CTA GAA TCA GAA 000 Thr Giu Ile Arg Ala Thr Leu Olu Ser 0Th Gly 280 285 TGG GAO ACT CAA AGA ATG CTA OAT TAC TCT TTG Trp Glu Thr Gin Arg Met Leu Asp Tyr Ser Leu 295 300 GAC AAA OTT TCC AGO AAA GAA CCT CTC AGT CCG Asp Lye Val Ser Axg Lys Oiu Pro Leu Ser Pro 310 315 CTO TCA CCA AGO OCT CCA 000 AAA GOC ATG 0CC Leu Ser Pro Arg Ala Pro Gly Lye Gly Met Ala 325 330 33S GGA ACC CTO CAT TCG OCT CAT OCT'AAA TAC ATT Gly Thr Leu His Ser Ala His Ala Lys Tyr Ile 345 350 TAT GOA GAA ATO AAG GAA ATT AAA GOT GGA COT Tyr Gly Glu Met Lye Glu Ile Lye Gly Gly Arg 360 365 OCT CCT GAG CTC CTC TOO TCC CAG TOG TTC OAT Ala Pro Glu Leu Leu Trp Ser Gin Trp Phe Asp 375 380
TOT
Cys
ACT
Thr
TAC
Tyr
GCA
Ala
TOC
Cys 240
AAT
AAT
GCA
Ala
TOT
Cys
CIT
Leu 320
TAT
Tyr
AGA
Arg
OGA
Gly
TTT.
Phe 624 672 720 816 912 ATT GAT Ile Asp 355 TCC AAG Ser Lys 1008 1056 1104 1152 1200 1248 Glu Tyr 370 CCO TTC Pro Phe AAA TIC Lys Phe ATI GGA CCG AAT GGA Ile Gly Pro Asn Oly 390 CTT TAT TIG ATC OGA Leu Tyr Leu Ile Gly 405 CTC CTG CAC ACA Leu Leu His Thr 395 GCA GGC ATA ATT Ala Gly Ile Ile 410 000 AAA Gly Lye GAC GAA Asp Giu 415 39 CTG CAT OAA CTA OAT GAG OCT OCT CCC ATT I Leu His Glu Leu Asp Glu Ala Ala Pro Ile 420 425 GAC GCG AAA AGC OTT CTT CCA GAA GAT OAA 4 Asp Ala Lys Ser Val Leu Pro Glu. Asp Glu 4 435 440 ACA GOT OTA TCC AAA AAC CCT ATC GAG TTG Thr Gly Val Ser Lys Asn Pro Ile Giu Leu 450 455 AAT TG AGA GAG AGT GTA ATG GCA ATA OTC Asn Trp Arg Giu Ser Val Met Ala Ile Val 465 470 OTT GTG ACA TTT CTG GCC ATC AAO ACG GTC Val Val Thr Phe Leu Ala Ile Lys Thr Val I 485 490 TOG AGA CCC AGA AAG AAA AGA ATC GTC AGA Trp Arg Pro Arg Lys Lys Arg Ile Val Arg 500 505 TCC CGA CTA AAC CAT TTT GAG ATO AGA GGC Ser Arg Leu Asn His Phe Glu Met Arg Gly I 515 520 AGA TAA Arg INFORMATION FOR SEQ ID NO:8: SEQUENCE CHARACTERISTICS: LENGTH: 529 amino acids TYPE: amino acid TOPOLOGY: linear (ii) MOLECULE TYPE: protein (xi) SEQUENCE DESCRIPTION: SEQ ID 6 Met Asp Leu Phe Pro Ile Leu Val Val Val I 1 5 Leu Gly Lys Phe Gin Ile Val Phe Pro Asp C Arg Pro Val Vai Gly Asp Ser Arg His Cys I Gin Phe Asp Gly Ser Arg Ser Gin Thr Ile I 55 Val Oly Ile Thr Pro Ser Lys Ser Asp Oly P 70 Lys Trp Val Thr Thr Cys Asp Phe Arg Trp 1 90 Thr His Ser Ile His His Leu Arg Pro Thr I 100 105 Ala Leu Gln Arg Tyr Lys Asp Gly Ser Leu I 115 120 Pro Giu Ser Cys Gly Tyr Ala Thr Val Thr 1 130 135 GAT CAC CCA CAA ATG CCT Asp His Pro Gin Met Pro 430 GAG ATA TTC TTC OGA GAC 3iu Ile Phe Phe Gly Asp 445 ATT CAA OGA TOG TTC TCA lie Gin Giy Trp Phe Ser 460 GGA ATT OT CTA CTC ATC Giy Ile Vai Leu Leu Ile 475 480 CG0 GTG CTT AAT TOT CTC krg Val Leu Asn Cys Leu 495 CAA GAA OTA OAT OTT OAA 31n Glu Val Asp Val Glu 510 ErT CCT GAA TAT OTT AAG Phe Pro Glu Tyr Val Lys 525 1296 1344 1392 1440 1488 1536 1584 1590 TO: 8: ~eu Met ;In Asn rro Gln .eu Thr ,he Ile .yr Gly :hr Ser :le Asn Lsp Ser 140 Val Gin Val Thr Pro His His Val Gly 145 150 Val Asp Asp Tyr Arg Gly His 155 160 Trp lie Asp Pro Leu Asp Asp Pro Tyr 225 Glu Val cys Arg Gin 305 Asp Thr Thr Glu Gly 385 Phe Leu Asp 165 Val His Asn 180 Cys Ala Gin 195 Glu Gly Ala Pro Asn Met Lys Gly Leu 245 Gin 5cr Ile 260 Ala Gly Thr 275 Leu Thr Trp Thr Trp Asp Ser Tyr Leu 325 Ile Asn Gly 340 Ile Asp Tyr 355 Ser Lys Ala Phe Lys Ile Phe Pro Leu 405 Glu Leu Asp 420 Lys Ser Val 435 Phe Pro Gly Giy Glu 170 Ser Ser Val Trp Ile 185 Ser Phe Lys Asn Ile 200 Leu Val Ser Asp Arg 215 Pro Gly Ser Thr Vai 230 Arg Ple Thr Asn Gly 250 Arg Giu Lys Lys Ile 265 Glu Lie Arg Aia Thr 280 Glu Thr Gin Arg Met 295 Lys Val Ser Arg Lye 310 Ser Pro Arg Ala Pro 330 Thr Leu His Ser Ala 345 Gly Glu Met Lys Glu 360 Pro Glu Leu Leu Trp 375 Gly Pro Asn Gly Leu 390 Tyr Leu Ile Gly Ala 410 Cys I Pro I Lys I Phe Cys 235 Glu Ser Leu Leu Glu 315 Gly His Ile Ser Leu 395 Gly Asp Glu Ile Gly 475 Arg er ys det a1 220 Ile rrp Ala lu Asp 300 Pro LyS Ala Lys Gln 380 His Ile His Ile Gln 460 Ile Val Thr Asn Phe Cys 175 Ser Gln Lye Thr 190 Thr Ala Ser Tyr 205 Phe His Ser Ala Met Asp Phe Cys 240 Met Gly Leu Asn 255 Ile Phe Pro Asn 270 Ser Glu Giy Ala 285 Tyr Ser Leu Cys Leu Ser Pro Leu 320 Gly Met Ala Tyr 335 Lys Tyr Ile Arg 350 Gly Gly Arg Gly 365 Trp Phe Asp Phe Thr Gly Lys Thr 400 Ile Asp Glu Asp 415 Pro Gln Met Pro 430 Phe Phe Giy Asp 445 Giy Trp Phe Ser Val Leu Leu Ile 480 Leu Asn Cys Leu 495 Glu Ala Ala Leu Pro Glu 440 Thr Gly Val 450 Ser Lys Asn Pro Ile 455 Pro Ile 425 Asp Glu Glu Leu Ile Vai Thr Val Asn Trp Arg Glu 465 Vai Vai Thr Phe Trp Arg Pro Arg 500 Ser Val Met Ala 470 Leu Ala Ile Lys 485 Lys Lys Arg Ile 490 Val Arg 505 Gin Glu Val Asp Val Glu 41 Arg Leu Asn His Phe Glu Met Arg Gly Phe Pro Glu Tyr Val Lys S20 525 INFORMATION FOR SEQ ID NO:9: Wi SEQUENCE CHARACTERISTICS: LENGTH: 1569 base pairs TYPE: nucleic acid STRANDEDNESS: double TOPOLOGY: linear (ii) MOLECULE TYPE: other nucleic acid DESCRIPTION: /desc '?DNA" (ix) FEATURE: NAME/KEY: CDS LOCATION: 1. .1566 (xi) SEQUENCE DESCRIPTION: SEQ ID NO:9: ATG AAT ATA CCT TGC TTT OCT GTG ATC CTC Met Asn Ile Pro Cys Pile Ala Val Ile Leu AI3C TTA GCT Ser Leu. Ala CTO GGA GAA TTC CCC Leu Gly Glu Phe Pro ACC CCC ATA GAC ATG Tin- Pro Ile Asp Met GAG GAA GAA GOT TGC Glu Glu Glu Gly Cys so AAG AGT GOT TAC CTA Lys 5cr Gly Tyr Leu 000 OTT GTG AAT GAG Gly Val Val Ann Glu ACC ACC ACC TTC AAA Tilr Thr Thr Pile Lys 100 CGT GAT GCC TAC AAC Arg Asp Ala Tyr An 115 TCT CTA CAC ACC COG Leu His Thr Pro 130 ACA ACC AAA GAA CC Thr Thr Lys Glu Ala 150 GAC ATA TAT GGC AGO Asp Ile Tyr Gly Arg 165 10 TTG TAT ACO ATT CCC GAG AAA Leu Tyr Tin- Ile Pro Glu Lys 25 ATC CAT CTT AGT TGC CCT AAT Ile His Leu. 5cr Cys Pro An 40 AAT ACA GAG TCT CCT Ti'C ACC Asn Thr (flu Ser Pro Phe Tin- 55 0CC CAT CA0 AAG GTC CCA GGA Ala His Gln Lys Val Pro Gly GCA GAG ACA TAC ACA AAC TT1T Ala Glu Thr Tyr Thr Ann Phe 90 AGO AAG CAC TTT AAA CCT ACA Arg Lys His Phe Lys Pro Tilr 105 TGO AAA OTA TCA 000 GAC CCC Trp Lys Val Ser Gly Asp Pro 120 125 TAT CCC GAC AGC AGC TOG TTA Tyr Pro Asp Ser Ser Trp Leu 135 140 CTT CTT ATA ATA TOG CCA AGC Leu Leu Ile Ile Ser Pro Ser ACT ACA Thr Thr ATA GAG Ile Glu AAC ATG Ann Met TAC TTC Tyr Pile TTT ACA Pile Thr GTC OGA Val Gly OTO OCT Val Ala 110 CGA TAT Arg Tyr
AGO
Arg
ATT
Ile
CCT
155 CCC ATG TTC ACC CTT CAC TCT Thr Leu. His Ser Pro Met Pile Pro 170 5cr Oly 17S AAA TOT TCC AAO CTC TAT CCT TCT GTC CCC TCT TOT ACA ACC AAC CAT Lys Cys Ser Lys Leu Tyr Pro 5cr Val Pro 5cr Cys Thr Thr Ann His 190 185 190 42
GAT
Asp
GAC
ASP
ATC
Ile 225
TCC
Ser
GGA
Gly ccc Pro
CAT
His
ACG
Thr 305
AGC
Ser
TTG
Leu
AGO
Arg
CAG
Gin
GGT
Oly 385
AAA
Lys
CCT
Pro
GAT
Asp TAC ACA TTG TOG TTG CCA GAA OAT TCT.
Tyr Thr Leu Trp Leu Pro Giu Asp Ser 195 200 ATC TTC ACT TCC AGC AGT OGA CAG AAG Ile Phe Thr Ser Ser Ser Oly Gin Lys 210 215 TGC GGA TTC AAG OAT GAA AGO OGA TTT Cys Oiy Phe Lys Asp Oiu Arg Giy Phe 230 TGT AAG CTO ACA TTO TGC 000 AAA CCT Cys Lys Leu Thr Leu Cys Gly Lys Pro 245 250 ACT TOG GTC TCT TTT ACA AAG CCG GAC Thr Trp Val Ser Phe Thr Lys Pro Asp 260 265 AAC CAG TTA GTC AAT ATA CAT AAC GAC Asn Gin Leu Val Asn Ile His Asn Asp 275 280 CTO ATC OTO GAC OAT ATC ATC AAG AAO Leu Ile Val Asp Asp Ile Ile Lys Lys 290 295 CTG GAA ACT ATA CTT ATO TCT CAA TCA Leu Oiu Thr Ile Leu Met Ser Gin Ser 310 CAT TTC AGA AAG TTA OTT CCA OGA TAT His Phe Arg Lys Leu Vai Pro Gly Tyr 325 330 AAC GGC AGC TTA ATO GAA ACA PAT GTC Asn Giy Ser Leu Met Oiu Thr Asn Val 340 345 TOO OCO GAC ATT TTO CCT TCT AGO GGA Trp Aia Asp Ile Leu Pro Ser Arg Giy 355 360 TGC ATO GAC CCT OTC AAA 000 GTC CTC Cys Met Asp Pro Vai Lys Oly Vai Leu 370 375 CCG OAT GGA CAA ATA TTO ATT CCA GAG Pro Asp Gly Gin Ile Leu Ile Pro Giu 390 CAG CAT ATO GAT CTG TTO AAA GCA OCT Gin His Met Asp Leu Leu Lys Ala Ala
A(T
Ser
GCC
Ala
TAC
Tyr 235
GGA
Oly
OTT
Vai
AGA
Arg CTG AGT TTO Leu Scr Leu 205 ATO PAT 000 Met Asfl Gly 220 AGA TCC TTG Arg Ser Leu ATT AGG CTO Ile Ar; Leu CAT OTO TG His Val Trp 270 CTA OAT GAG Leu Asp Oiu 285 ATT TOC Ile Cys TCT CC Ser Arg AAG GGA Lys Giy 240 TTC GAC Phe Asp 255 T0C ACT Cys Thr GTT OAA Val Giu TTA GAC Leu Asp COG TTG Arg Leu 320 ACT ATT Thr Ile 335 AGA GAO Ar; Oiu 300 OTT AOT Val Ser 315 OGA AAA Giy Lys GAG TOT Oiu Cys TTT AGA Phe Ar; OCT TAC Ala Tyr 624 672 720 768 B 16 864 912 960 1008 1056 ii104 1152 1200 1248 1296 1344 1392
TAC
Tyr
TOT
Cys
TTC
Phe
ATO
Met 395
ATC
Met
AAG
LYS
CA
Gin TAC AAA AGA GTT Tyr Lys Arg Vai 350 CTG AAA GTC GGA Leu Lys Val Gly 365 PAC GGA ATT ATC Asn Gly Ile Ile 380 CAG TCA GAG CAG Gin Scr Oiu Gin TTT CCT CTC COT Phe Pro Leu Ar; 415 OAT OGA AAT 0CC Asp Gly Asn Ala 430 AAA TCT GTO TCG Lys Ser Val Ser 445 TTA ATC Leu Ile TTrT OTT Phe Val 435 405 AAC AGA Asn Arg 420 GAT CTC Asp Leu GAG OCA GTC Oiu Ala Vai CAT ATO CCT His Met Pro 440 410 TTC AAG Phe Lys 425 OAT OTT Asp Vai OTC GAC CTO GOC CTO CCT CAT TOO 000 TTC TGG TTG TTA GTC 000 OCA Val Asp Leu Gly Leu Pro His Trp Gly Phe Trp Leu Leu Val Oly Ala 450 455 460 43 ACA OTA GTA 0CC TTT GTG GTC TTG GCG TGC TTG CTC COT GTA TOT TOT Thr Val Val Ala Phe Val Val Leu Ala Cys Leu Leu Arg Vai Cys Cys 465 470 475 480 AGO AGA ATG AGA AGO AGA AGO TCA CTO COT GCC ACT CAG GAT ATC CCC Arg Arg Met Arg Arg Arg Arg Ser Leu Arg Ala Thr Gin Asp Ile Pro 485 490 495 CTC AGC GTT 0CC CCT GCC CCT GTC CCT COT 0CC AAA GTO GTO TCA TCA Leu Ser Val Ala Pro Ala Pro Vai Pro Arg Ala Lys Val Val Ser Ser 500 505 510 TOO GAG TCT TCT AAA 000 CTC CCA GOT ACT TGA Trp Oiu Ser Ser Lys Oly Leu Pro Gly Thr 515 520 INFORMATION FOR SEQ ID Wi SEQUENCE CHARACTERISTICS: LENGTH: 522 amino acids TYPE: amino acid TOPOLOGY: linear (ii) MOLECULE TYPE: protein 1440 14B88 1536 1569 (xi) SEQUENCE Met Asn Ile Pro Cys Ser Leu Oly Olu Phe Trp Thr Pro Ile Asp Ser Glu Glu Olu Gly Leu Lys Ser Gly Tyr Thr Oly Val Val An Val Thr Thr Thr Phe 100 Cys Arg Asp Ala Tyr 115 Giu Ser Leu His Thr 130 Thr Thr Thr Lys Olu 145 Met Asp Ile Tyr Gly 165 Lys Cys Ser Lys Leu 180 Asp Tyr Thr Leu Trp 195 DESCRIPTION: SEQ ID NO:l0: Phe Ala Val Ile Leu Ser Leu Ala Thr Thr His 10 Tyr His 40 Thr His Glu Lys 120 Pro Leu Leu Ser Giu 200 Ile Pro Olu Lye Ile Olu Lye Ser Cye Pro Ann Aan Met Leu Pro Pile Val Pro Thr An Lye Pro Gly Asp Ser Trp 140 Ser Pro 155 Pro Met Ser Cyr.
Thr Tyr Pile Oly Phe Thr Phe Val Gly Thr Val Ala 110 Pro Arg Tyr 125 Leu Arg Thr Ser le Val Pile Pro Ser 175 Thr Thr An 190 Ser Leu Ser Leu Ile Cys 205 Asp Ile 210 Pile Thr Ser Ser Gly Gin Lye Ala Ann Gly Ser Arg -44- Ile Cys Gly Phe Lys Asp Giu Arg Gly Phe Tyr j 225 230 235 Ser Cys Lys Leu Thr Leu Cys Gly Lys Pro Gly 245 250 Gly Thr Trp Val Ser Phe Thr Lys Pro Asp Val 260 265 Pro Asn Gin Leu Val Asn Ile His Asn Asp Arg 275 280 His Leu Ile Val Asp Asp Ile Ile Lys Lys Arg 290 295 Thr Leu Glu Thr Ile Leu Met Ser Gin Ser Val 305 310 315 Ser His Phe Arg Lys Len Val Pro Gly Tyr Gly 325 330 Leu Asn Giy Ser Len Met Giu Thx Asn Vai Tyr 340 345 Arg Trp Ala Asp Ile Leu Pro Ser Arg Giy Cys 355 360 Gin Cys Met Asp Pro Val Lys Giy Val Leu Phe 370 375 Gly Pro Asp Giy Gin Ile Leu Ile Pro Giu Met 385 390 395 Lys Gln His Met Asp Leu Leu Lys Ala Ala Met 405 410 Pro Leu Ile Asn Arg Glu Ala Val Phe Lys Lys 420 425 Asp Phe Val Asp Len His Met Pro Asp Val Gln 435 440 Vai Asp Leu Gly Leu Pro His Trp Gly Phe Trp 450 455 Thr Vai Val Ala Phe Val Val Leu Ala Cys Leu 465 470 475 Arg Arg Met Axg Arg Arg ArS Ser Leu Arg Ala 485 490 Leu Ser Val Ala Pro Ala Pro Val Pro Arg Ala 500 505 -Trp-Glu--Ser-Ser--L-ys-Gy-Leu-Pro--Gly-Thr-- 515 520 Ser Leu Lys Gly 240 Arg Leu Phe Asp 255 Val Trp Cys Thr 270 Asp Glu Vai Glu 285 Glu Cys Len Asp Phe Arg Arg Len 320 Ala Tyr Thr Ile 335 Lys Arg Vai Asp 350 Lys Val Gly Gin 365 Gly Ile Ile Lys Ser Giu Gln Len 400 Pro Leu Arg His 415 Gly Asn Ala Asp 430 Ser Val Ser Asp 445 Leu Vai Gly Ala Arg Val Cys Cys 480 Gln Asp Ile Pro 495 Val Val Ser Ser 510

Claims (26)

1. A composition comprising a non-human mammalian unfertilized oocyte comprising a heterologous polynucleotide integrated into the genome of said oocyte, wherein the polynucleotide is introduced into the oocyte by microinjection into the perivitelline space, and wherein the heterologous polynucleotide is a retroviral vector.
2. The composition of claim 1, wherein said unfertilized oocyte is a prematuration oocyte.
3. The composition of claim 1, wherein said unfertilized oocyte is a prefertilization oocyte.
4. The composition of claim 1, wherein said polynucleotide is the proviral form of a retroviral vector.
The composition of claim 1, wherein said non-human animal is a mammal.
6. The composition of claim 1, wherein said mammal is a cow.
7. A method for introducing a heterologous polynucleotide into the genome of a non-human mammalian unfertilized oocyte, comprising: a) providing: i) a non-human mammalian unfertilized egg comprising an oocyte having a plasma membrane and a zona pellucida, said plasma membrane and said zona pellucida defining a perivitelline space; ii) an aqueous solution comprising a heterologous polynucleotide, wherein the heterologous polynucleotide is a retroviral vector; and b) introducing said solution comprising said heterologous polynucleotide into said perivitelline space under conditions which permit the introduction of said heterologous polynucleotide into the genome of said oocyte.
8. The method of claim 7, wherein said heterologous polynucleotide encodes a protein of interest.
9. The method of claim 7, wherein said unfertilized oocyte is a pre-maturation oocyte.
The method of claim 7, wherein said unfertilized oocyte is a pre-fertilization oocyte.
11. The method of claim 7, wherein said heterologous polynucleotide is contained within genome of a recombinant retrovirus.
12. A method for the production of a transgenic non-human animal comprising: a) providing: [R:\PAL Specifications\442283]70712spec.doc:gcc i) an unfertilized egg comprising an oocyte having a plasma membrane and a zona pellucida, said plasma membrane and said zona pellucida defining a perivitelline space; ii) an aqueous solution containing infectious retrovirus; b) introducing said solution containing infectious retrovirus into said perivitelline space under conditions which permit the infection of said oocyte; and c) contacting said infected oocyte with sperm under conditions which permit the fertilization of said infected oocyte to produce an embryo.
13. The method of claim 12 further comprising following the fertilization of said infected oocyte the step of transferring said embryo into a hormonally sychronized nonhuman recipient animal.
14. The method of claim 13 further comprising the step of allowing said embryo to develop to term.
The method of claim 14 further comprising identifying at least one transgenic offspring.
16. The method of claim 12, wherein said unfertilized egg comprises a pre- maturation oocyte.
17. The method of claim 12, wherein said unfertilized egg comprises an pre- fertilization oocyte.
18. The method of claim 16 further comprising following the introduction of said solution containing infectious retrovirus into said pre-maturation oocyte, the further step of culturing said infected pre-maturation oocyte under conditions which permit the maturation of said pre-maturation oocyte.
19. The method of claim 12, wherein said infectious retrovirus comprises a heterologous membrane-associated protein.
The method of claim 19, wherein said heterologous membrane-associated protein is a G glycoprotein selected from a virus within the family Rhabdoviridae.
21. The method of claim 20, wherein said G glycoprotein is selected from the group comprising the G glycoprotein of vesicular stomatitis virus, Piry virus, Chandipura virus, Spring viremia of carp virus and Mokola virus.
22. The method of claim 12, wherein said non-human animal is a mammal.
23. The method of claim 22, wherein said mammal is a cow.
24. A composition comprising a non-human mammalian unfertilized oocyte comprising a heterologous polynucleotide integrated into the genome of said oocyte, substantially as hereinbefore described with reference to any one of the examples.
I R:\PA L Specifications\442283]707 1 2spec.doc:gcc A method for introducing a heterologous polynucleotide into the genome of a non-human mammalian unfertilized oocyte, substantially as hereinbefore described with reference to any one of the examples.
26. A method for the production of a transgenic non-human animal, substantially as hereinbefore described with reference to any one of the examples. Dated 5 July, 2006 Wisconsin Alumni Research Foundation Patent Attorneys for the Applicant/Nominated Person SPRUSON FERGUSON [R:\PAL Specifications\4422B3170712spcc.doc:gcc
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Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
Friedrich et al. Gen Develop,1991. 599:1513-23 *
Lock et al. EMBO J, 1988. 7(13): 4169-77 *
Reynolds RK et al. J Virol, 1978. 28(2): 665-70 *

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