title: Genome structure of Abelson murine leukemia virus variants: proviruses in fibroblasts and lymphoid cells.
abstract: We have prepared full-length DNA clones of the Abelson murine leukemia virus (A-MuLV) genome. A specific probe homologous to the central portion of the A-MuLV genome was prepared by nick translation of a subcloned restriction fraction from the cloned DNA. The probe was used to examine the genome structure of several A-MuLV variants. The conclusions are: (i) three viruses coding for Abelson-specific proteins of molecular weight 120,000, 100,000, and 90,000 had genomes indistinguishable in size, suggesting that the shorter proteins are the result of early translational termination; (ii) compared with the genome encoding the 120,000-dalton (120K) protein, a genome coding for a 160K protein was 0.8 kilobase larger in the A-MuLV-specific region; and (iii) a genome coding for a 92K protein had a 700-base pair deletion internal to the coding region. This mutant was transformation defective: its 92K protein lacked the protein kinase activity normally associated with the A-MuLV protein, and cells containing the virus were not morphologically transformed. In addition, we determined the number of A-MuLV proviruses in each of several transformed fibroblast and lymphoid cells prepared by infection in vitro. These experiments show that a single copy of the A-MuLV provirus is sufficient to transform both types of cells and that nonproducer cells generally have only one integrated provirus.
mesh_terms: D000011:Abelson murine leukemia virus / Q000235:genetics* / Q000502:physiology; D000818:Animals; D002460:Cell Line; D002472:Cell Transformation, Viral; D005347:Fibroblasts; D005814:Genes, Viral; D009052:Leukemia Virus, Murine / Q000235:genetics*; D008214:Lymphocytes; D051379:Mice; D009154:Mutation; D011494:Protein Kinases / Q000378:metabolism; D014764:Viral Proteins / Q000235:genetics*
chemical_list: D014764:Viral Proteins; D011494:Protein Kinases