Abstract
The adenovirus Ad5(pymT) has been used to express middle T antigen at very high levels in 293 cells. The middle T antigen produced was localized to membranes and was modified in the same way as that expressed in polyoma virus-infected mouse cells. It was phosphorylated in vivo on serine residues and in vitro on tyrosine residues. The in vivo phosphorylations occurred between residues 223 and 275. The middle T antigen encoded by A d5(pymT) was phosphorylated in vitro in a complex with human pp60c-src. Interestingly, the extreme overexpression of middle T antigen did not cause a parallel increase in the amount of complex; most of the pp60c-src remained unassociated. Immunoaffinity purification resulted in approximately 100 micrograms of middle T antigen from a 100-mm tissue culture dish. Several cell proteins copurified with the Ad5(pymT)-derived middle T antigen. Two of these, the 74- and 63-kilodalton species, are of particular interest because they were also purified from mouse tumors expressing middle T antigen.
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- Berkner K. L., Schaffhausen B. S., Roberts T. M., Sharp P. A. Abundant expression of polyomavirus middle T antigen and dihydrofolate reductase in an adenovirus recombinant. J Virol. 1987 Apr;61(4):1213–1220. doi: 10.1128/jvi.61.4.1213-1220.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bolen J. B., Thiele C. J., Israel M. A., Yonemoto W., Lipsich L. A., Brugge J. S. Enhancement of cellular src gene product associated tyrosyl kinase activity following polyoma virus infection and transformation. Cell. 1984 Oct;38(3):767–777. doi: 10.1016/0092-8674(84)90272-1. [DOI] [PubMed] [Google Scholar]
- Carmichael G. G., Schaffhausen B. S., Dorsky D. I., Oliver D. B., Benjamin T. L. Carboxy terminus of polyoma middle-sized tumor antigen is required for attachment to membranes, associated protein kinase activities, and cell transformation. Proc Natl Acad Sci U S A. 1982 Jun;79(11):3579–3583. doi: 10.1073/pnas.79.11.3579. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Carmichael G., Schaffhausen B. S., Mandel G., Liang T. J., Benjamin T. L. Transformation by polyoma virus is drastically reduced by substitution of phenylalanine for tyrosine at residue 315 of middle-sized tumor antigen. Proc Natl Acad Sci U S A. 1984 Feb;81(3):679–683. doi: 10.1073/pnas.81.3.679. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Courtneidge S. A. Activation of the pp60c-src kinase by middle T antigen binding or by dephosphorylation. EMBO J. 1985 Jun;4(6):1471–1477. doi: 10.1002/j.1460-2075.1985.tb03805.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Courtneidge S. A., Smith A. E. Polyoma virus transforming protein associates with the product of the c-src cellular gene. Nature. 1983 Jun 2;303(5916):435–439. doi: 10.1038/303435a0. [DOI] [PubMed] [Google Scholar]
- Courtneidge S. A., Smith A. E. The complex of polyoma virus middle-T antigen and pp60c-src. EMBO J. 1984 Mar;3(3):585–591. doi: 10.1002/j.1460-2075.1984.tb01852.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Feunteun J., Sompayrac L., Fluck M., Benjamin T. Localization of gene functions in polyoma virus DNA. Proc Natl Acad Sci U S A. 1976 Nov;73(11):4169–4173. doi: 10.1073/pnas.73.11.4169. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Grussenmeyer T., Scheidtmann K. H., Hutchinson M. A., Eckhart W., Walter G. Complexes of polyoma virus medium T antigen and cellular proteins. Proc Natl Acad Sci U S A. 1985 Dec;82(23):7952–7954. doi: 10.1073/pnas.82.23.7952. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hunter T., Sefton B. M. Transforming gene product of Rous sarcoma virus phosphorylates tyrosine. Proc Natl Acad Sci U S A. 1980 Mar;77(3):1311–1315. doi: 10.1073/pnas.77.3.1311. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kaplan D. R., Bockus B., Roberts T. M., Bolen J., Israel M., Schaffhausen B. S. Large-scale production of polyoma middle T antigen by using genetically engineered tumors. Mol Cell Biol. 1985 Jul;5(7):1795–1799. doi: 10.1128/mcb.5.7.1795. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Mansour S. L., Grodzicker T., Tjian R. An adenovirus vector system used to express polyoma virus tumor antigens. Proc Natl Acad Sci U S A. 1985 Mar;82(5):1359–1363. doi: 10.1073/pnas.82.5.1359. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pallas D. C., Schley C., Mahoney M., Harlow E., Schaffhausen B. S., Roberts T. M. Polyomavirus small t antigen: overproduction in bacteria, purification, and utilization for monoclonal and polyclonal antibody production. J Virol. 1986 Dec;60(3):1075–1084. doi: 10.1128/jvi.60.3.1075-1084.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Parsons S. J., McCarley D. J., Ely C. M., Benjamin D. C., Parsons J. T. Monoclonal antibodies to Rous sarcoma virus pp60src react with enzymatically active cellular pp60src of avian and mammalian origin. J Virol. 1984 Aug;51(2):272–282. doi: 10.1128/jvi.51.2.272-282.1984. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schaffhausen B. S., Benjamin T. L. Phosphorylation of polyoma T antigens. Cell. 1979 Dec;18(4):935–946. doi: 10.1016/0092-8674(79)90206-x. [DOI] [PubMed] [Google Scholar]
- Schaffhausen B. S., Silver J. E., Benjamin T. L. Tumor antigen(s) in cell productively infected by wild-type polyoma virus and mutant NG-18. Proc Natl Acad Sci U S A. 1978 Jan;75(1):79–83. doi: 10.1073/pnas.75.1.79. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schaffhausen B., Benjamin T. L. Comparison of phosphorylation of two polyoma virus middle T antigens in vivo and in vitro. J Virol. 1981 Oct;40(1):184–196. doi: 10.1128/jvi.40.1.184-196.1981. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schaffhausen B., Benjamin T. L., Lodge J., Kaplan D., Roberts T. M. Expression of polyoma early gene products in E. coli. Nucleic Acids Res. 1985 Jan 25;13(2):501–519. doi: 10.1093/nar/13.2.501. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schaffhausen B. Transforming genes and gene products of polyoma and SV40. CRC Crit Rev Biochem. 1982;13(3):215–286. doi: 10.3109/10409238209114230. [DOI] [PubMed] [Google Scholar]
- Segawa K., Ito Y. Differential subcellular localization of in vivo-phosphorylated and nonphosphorylated middle-sized tumor antigen of polyoma virus and its relationship to middle-sized tumor antigen phosphorylating activity in vitro. Proc Natl Acad Sci U S A. 1982 Nov;79(22):6812–6816. doi: 10.1073/pnas.79.22.6812. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Takemoto K. K., Bond S. B., Haase A. T., Ting R. C. Polyoma virus-human cell interactions: persistence of T-antigen in two cell lines with and without transformation. J Virol. 1978 Jan;25(1):326–330. doi: 10.1128/jvi.25.1.326-330.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Templeton D., Voronova A., Eckhart W. Construction and expression of a recombinant DNA gene encoding a polyomavirus middle-size tumor antigen with the carboxyl terminus of the vesicular stomatitis virus glycoprotein G. Mol Cell Biol. 1984 Feb;4(2):282–289. doi: 10.1128/mcb.4.2.282. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Weiner A. M., Platt T., Weber K. Amino-terminal sequence analysis of proteins purified on a nanomole scale by gel electrophoresis. J Biol Chem. 1972 May 25;247(10):3242–3251. [PubMed] [Google Scholar]
- Zhu Z. Y., Veldman G. M., Cowie A., Carr A., Schaffhausen B., Kamen R. Construction and functional characterization of polyomavirus genomes that separately encode the three early proteins. J Virol. 1984 Jul;51(1):170–180. doi: 10.1128/jvi.51.1.170-180.1984. [DOI] [PMC free article] [PubMed] [Google Scholar]