Association of gag-myc proteins from avian myelocytomatosis virus wild-type and mutants with chromatin. (2024)

PMCID: PMC553136

T Bunte, I Greiser-Wilke, P Donner, and K Moelling

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Abstract

The localization of the transformation-specific proteins was analyzed in quail embryo fibroblast cell lines transformed by wild-type avian myelocytomatosis virus MC29 and by three of its deletion mutants, Q10A , Q10C , and Q10H , with altered transforming capacities, and in a chicken fibroblast cell line transformed by the avian erythroblastosis virus (AEV). These viruses code for polyproteins consisting of part of the gag gene and of a transformation-specific region, myc for MC29 and erb A for AEV. Analysis by indirect immunofluorescence using monoclonal antibodies against p19, the N-terminal region of the polyprotein, showed that the gag-myc proteins in cells transformed by the wild-type MC29 as well as by the three deletion mutants are located in the nucleus. In contrast, cells transformed by AEV, which express the gag-erb A protein, give rise to cytoplasmic fluorescence. Fractionation of cells into nuclear and cytoplasmic fractions and analysis by immunoprecipitation and gel electrophoresis confirmed these results. About 60% of the gag-myc proteins of wild-type as well as of mutant origin were found in the nucleus, while 90% of the gag-erb A protein was present in the cytoplasm. Also, pulse-chase analysis indicated that the gag-myc protein rapidly accumulates in the nucleus in just 30 min. Further, it was shown that the wild-type and also mutant gag-myc proteins are associated with isolated chromatin. Association to chromatin was also observed for the gag-myc protein from MC29-transformed bone marrow cells, which are believed to be the target cells for MC29 virus in vivo.

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• Abrams HD, Rohrschneider LR, Eisenman RN. Nuclear location of the putative transforming protein of avian myelocytomatosis virus. Cell. 1982 Jun;29(2):427–439. [PubMed] [Google Scholar]
• Bister K, Duesberg PH. Structure and specific sequences of avian erythroblastosis virus RNA: evidence for multiple classes of transforming genes among avian tumor viruses. Proc Natl Acad Sci U S A. 1979 Oct;76(10):5023–5027. [PMC free article] [PubMed] [Google Scholar]
• Bister K, Hayman MJ, Vogt PK. Defectiveness of avian myelocytomatosis virus MC29: isolation of long-term nonproducer cultures and analysis of virus-specific polypeptide synthesis. Virology. 1977 Oct 15;82(2):431–448. [PubMed] [Google Scholar]
• Bister K, Ramsay GM, Hayman MJ. Deletions within the transformation-specific RNA sequences of acute leukemia virus MC29 give rise to partially transformation-defective mutants. J Virol. 1982 Mar;41(3):754–766. [PMC free article] [PubMed] [Google Scholar]
• Brugge JS, Erikson RL. Identification of a transformation-specific antigen induced by an avian sarcoma virus. Nature. 1977 Sep 22;269(5626):346–348. [PubMed] [Google Scholar]
• Cleveland DW, Fischer SG, Kirschner MW, Laemmli UK. Peptide mapping by limited proteolysis in sodium dodecyl sulfate and analysis by gel electrophoresis. J Biol Chem. 1977 Feb 10;252(3):1102–1106. [PubMed] [Google Scholar]
• Donner P, Greiser-Wilke I, Moelling K. Nuclear localization and DNA binding of the transforming gene product of avian myelocytomatosis virus. Nature. 1982 Mar 18;296(5854):262–269. [PubMed] [Google Scholar]
• Erikson RL, Purchio AF, Erikson E, Collett MS, Brugge JS. Molecular events in cells transformed by Rous Sarcoma virus. J Cell Biol. 1980 Nov;87(2 Pt 1):319–325. [PMC free article] [PubMed] [Google Scholar]
• Gonda TJ, Sheiness DK, Fanshier L, Bishop JM, Moscovici C, Moscovici MG. The genome and the intracellular RNAs of avian myeloblastosis virus. Cell. 1981 Jan;23(1):279–290. [PubMed] [Google Scholar]
• Graf T, Beug H. Avian leukemia viruses: interaction with their target cells in vivo and in vitro. Biochim Biophys Acta. 1978 Nov 17;516(3):269–299. [PubMed] [Google Scholar]
• Greiser-Wilke I, Owada KM, Moelling K. Isolation of monoclonal antibodies against avian oncornaviral protein p19. J Virol. 1981 Jul;39(1):325–329. [PMC free article] [PubMed] [Google Scholar]
• Hayman MJ. Transforming proteins of avian retroviruses. J Gen Virol. 1981 Jan;52(Pt 1):1–14. [PubMed] [Google Scholar]
• Hayman MJ, Royer-Pokora B, Graf T. Defectiveness of avian erythroblastosis virus: synthesis of a 75K gag-related protein. Virology. 1979 Jan 15;92(1):31–45. [PubMed] [Google Scholar]
• Kessler SW. Rapid isolation of antigens from cells with a staphylococcal protein A-antibody adsorbent: parameters of the interaction of antibody-antigen complexes with protein A. J Immunol. 1975 Dec;115(6):1617–1624. [PubMed] [Google Scholar]
• Khalaf RM, Bainbridge DR. Nomarski differential interference contrast studies of murine lymphocytes. Eur J Immunol. 1981 Oct;11(10):816–824. [PubMed] [Google Scholar]
• Lai MM, Neil JC, Vogt PK. Cell-free translation of avian erythroblastosis virus RNA yields two specific and distinct proteins with molecular weights of 75,000 and 40,000. Virology. 1980 Jan 30;100(2):475–483. [PubMed] [Google Scholar]
• Lapeyre JN, Bekhoe I. Effects of 5-bromo-2'-deoxyuridine and dimethyl sulfoxide on properties and structure of chromatin. J Mol Biol. 1974 Oct 15;89(1):137–162. [PubMed] [Google Scholar]
• Pawson T, Martin GS. Cell-free translation of avian erythroblastosis virus RNA. J Virol. 1980 Apr;34(1):280–284. [PMC free article] [PubMed] [Google Scholar]
• Ramsay G, Graf T, Hayman MJ. Mutants of avian myelocytomatosis virus with smaller gag gene-related proteins have an altered transforming ability. Nature. 1980 Nov 13;288(5787):170–172. [PubMed] [Google Scholar]
• Ramsay GM, Hayman MJ. Isolation and biochemical characterization of partially transformation-defective mutants of avian myelocytomatosis virus strain MC29: localization of the mutation to the myc domain of the 110,000-dalton gag-myc polyprotein. J Virol. 1982 Mar;41(3):745–753. [PMC free article] [PubMed] [Google Scholar]