Abstract
We constructed deletion mutations which removed N-terminal coding sequences of various lengths from a cloned polyoma middle-size T antigen (MT antigen) gene. We introduced the MT antigen genes into a simian virus 40 expression vector so that they were expressed at high levels under the control of the simian virus 40 late promoter in COS-1 cells. The deletion mutant genes synthesized truncated MT antigens whose size was consistent with the deletion of either 70 or 106 amino acids from N termini, owing to initiation of translation at internal methionine codons in the MT antigen-coding region. The truncated MT antigens were found in cell membrane fractions but failed to show MT antigen-associated protein kinase activity. The cloned deletion mutant DNAs failed to transform rat F2408 or mouse NIH 3T3 cells. Therefore, N-terminal amino acid sequences of the polyoma MT antigen, as well as C-terminal sequences, are important for protein kinase activity and cell transformation.
Full text
PDF![817](https://cdn.ncbi.nlm.nih.gov/pmc/blobs/7bf8/368818/6b57c9b7be13/molcellb00147-0007.png)
![818](https://cdn.ncbi.nlm.nih.gov/pmc/blobs/7bf8/368818/7fa6b173546c/molcellb00147-0008.png)
![819](https://cdn.ncbi.nlm.nih.gov/pmc/blobs/7bf8/368818/d0e316debd3d/molcellb00147-0009.png)
![820](https://cdn.ncbi.nlm.nih.gov/pmc/blobs/7bf8/368818/c6cb58348d92/molcellb00147-0010.png)
![821](https://cdn.ncbi.nlm.nih.gov/pmc/blobs/7bf8/368818/faad2fe09ac5/molcellb00147-0011.png)
Images in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- 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]
- 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]
- Eckhart W., Hutchinson M. A., Hunter T. An activity phosphorylating tyrosine in polyoma T antigen immunoprecipitates. Cell. 1979 Dec;18(4):925–933. doi: 10.1016/0092-8674(79)90205-8. [DOI] [PubMed] [Google Scholar]
- Friedmann T., Esty A., LaPorte P., Deininger P. The nucleotide sequence and genome organization of the polyoma early region: extensive nucleotide and amino acid homology with SV40. Cell. 1979 Jul;17(3):715–724. doi: 10.1016/0092-8674(79)90278-2. [DOI] [PubMed] [Google Scholar]
- Hutchinson M. A., Hunter T., Eckhart W. Characterization of T antigens in polyoma-infected and transformed cells. Cell. 1978 Sep;15(1):65–77. doi: 10.1016/0092-8674(78)90083-1. [DOI] [PubMed] [Google Scholar]
- Ito Y., Brocklehurst J. R., Dulbecco R. Virus-specific proteins in the plasma membrane of cells lytically infected or transformed by pol-oma virus. Proc Natl Acad Sci U S A. 1977 Oct;74(10):4666–4670. doi: 10.1073/pnas.74.10.4666. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Katinka M., Yaniv M. Deletions of N-terminal sequences of polyoma virus T-antigens reduce but do not abolish transformation of rat fibroblasts. Mol Cell Biol. 1982 Oct;2(10):1238–1246. doi: 10.1128/mcb.2.10.1238. [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., Dorai H., Arakere G., Benjamin T. L. Polyoma virus middle T antigen: relationship to cell membranes and apparent lack of ATP-binding activity. Mol Cell Biol. 1982 Oct;2(10):1187–1198. doi: 10.1128/mcb.2.10.1187. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Smith A. E., Smith R., Griffin B., Fried M. Protein kinase activity associated with polyoma virus middle T antigen in vitro. Cell. 1979 Dec;18(4):915–924. doi: 10.1016/0092-8674(79)90204-6. [DOI] [PubMed] [Google Scholar]
- Sprague J., Condra J. H., Arnheiter H., Lazzarini R. A. Expression of a recombinant DNA gene coding for the vesicular stomatitis virus nucleocapsid protein. J Virol. 1983 Feb;45(2):773–781. doi: 10.1128/jvi.45.2.773-781.1983. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Templeton D., Eckhart W. Mutation causing premature termination of the polyoma virus medium T antigen blocks cell transformation. J Virol. 1982 Mar;41(3):1014–1024. doi: 10.1128/jvi.41.3.1014-1024.1982. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Treisman R., Novak U., Favaloro J., Kamen R. Transformation of rat cells by an altered polyoma virus genome expressing only the middle-T protein. Nature. 1981 Aug 13;292(5824):595–600. doi: 10.1038/292595a0. [DOI] [PubMed] [Google Scholar]
- Walter G., Hutchinson M. A., Hunter T., Eckhart W. Antibodies specific for the polyoma virus middle-size tumor antigen. Proc Natl Acad Sci U S A. 1981 Aug;78(8):4882–4886. doi: 10.1073/pnas.78.8.4882. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Walter G., Hutchinson M. A., Hunter T., Eckhart W. Purification of polyoma virus medium-size tumor antigen by immunoaffinity chromatography. Proc Natl Acad Sci U S A. 1982 Jul;79(13):4025–4029. doi: 10.1073/pnas.79.13.4025. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wigler M., Pellicer A., Silverstein S., Axel R., Urlaub G., Chasin L. DNA-mediated transfer of the adenine phosphoribosyltransferase locus into mammalian cells. Proc Natl Acad Sci U S A. 1979 Mar;76(3):1373–1376. doi: 10.1073/pnas.76.3.1373. [DOI] [PMC free article] [PubMed] [Google Scholar]