title: Construction and properties of replication-competent murine retroviral vectors encoding methotrexate resistance.
abstract: A series of replication-competent Moloney murine leukemia virus vectors was constructed in which each vector contained a mutant dihydrofolate reductase (DHFR) cDNA insert in the U3 region of the viral long terminal repeat. Two of the resulting viruses, MLV (murine leukemia virus) DHFR*-5 and MLV DHFR*-7, were able to stably transfer methotrexate resistance to infected fibroblast cells upon multiple rounds of virus replication and in the absence of drug selection. Cell lines producing recombinant virus with high titers were established, which indicated that the insert did not grossly interfere with viral replication functions. These vectors should be useful for introducing and expressing foreign genes in vivo in tissues and whole animals in which virus spread is needed for efficient infection.
authors.affiliation: Whitehead Institute for Biomedical Research, Nine Cambridge Center, Massachusetts 02142.
authors.forename: H
authors.initials: H
authors.lastname: Stuhlmann
authors.forename: R
authors.initials: R
authors.lastname: Jaenisch
authors.forename: R C
authors.initials: RC
authors.lastname: Mulligan
mesh_terms: D000818:Animals; D001483:Base Sequence; D015139:Blotting, Southern; D003001:Cloning, Molecular; D004274:DNA, Recombinant / Q000096:biosynthesis; D004279:DNA, Viral / Q000096:biosynthesis; D004352:Drug Resistance, Microbial / Q000235:genetics; D005786:Gene Expression Regulation / Q000187:drug effects*; D005822:Genetic Vectors; D006801:Humans; D008727:Methotrexate / Q000494:pharmacology*; D051379:Mice; D008815:Mice, Inbred Strains; D008979:Moloney murine leukemia virus / Q000235:genetics*; D009154:Mutation; D009690:Nucleic Acid Conformation; D010957:Plasmids; D013762:Tetrahydrofolate Dehydrogenase / Q000235:genetics; D014162:Transfection; D014779:Virus Replication
chemical_list: D004274:DNA, Recombinant; D004279:DNA, Viral; D013762:Tetrahydrofolate Dehydrogenase; D008727:Methotrexate