Skip to main content
Journal of Virology logoLink to Journal of Virology
. 1997 Sep;71(9):6472–6478. doi: 10.1128/jvi.71.9.6472-6478.1997

Phosphorylation sites in polyomavirus large T antigen that regulate its function in viral, but not cellular, DNA synthesis.

A Chatterjee 1, B J Bockus 1, O V Gjørup 1, B S Schaffhausen 1
PMCID: PMC191921  PMID: 9261365

Abstract

Polyomavirus large T antigen (large T) is a highly phosphorylated protein that can be separated by proteolysis into two domains that have independent function. A cluster of phosphorylation sites was found in the protease-sensitive region connecting the N-terminal and C-terminal domains. Edman degradation of 32P-labeled protein identified serines 267, 271, and 274 and threonine 278 as sites of phosphorylation. Analysis of site-directed mutants confirmed directly that residues 271, 274, and 278 were phosphorylated. Threonine 278, shown here to be phosphorylated by cyclin/cyclin-dependent kinase activity, is required for viral DNA replication in either the full-length large T or C-terminal domain context. The serine phosphorylations are unimportant in the C-terminal domain context even though their mutations activates viral DNA replication in full-length large T. This finding suggests that these sites may function in relating the two domains to each other. Although the phosphorylation sites were involved in viral DNA replication, none was important for the ability of large T to drive cellular DNA replication as measured by bromodeoxyuridine incorporation, and they did not affect large T interactions with the Rb tumor suppressor family.

Full Text

The Full Text of this article is available as a PDF (619.5 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Bockus B. J., Schaffhausen B. Localization of the phosphorylations of polyomavirus large T antigen. J Virol. 1987 Apr;61(4):1155–1163. doi: 10.1128/jvi.61.4.1155-1163.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Bockus B. J., Schaffhausen B. Phosphorylation of polyomavirus large T antigen: effects of viral mutations and cell growth state. J Virol. 1987 Apr;61(4):1147–1154. doi: 10.1128/jvi.61.4.1147-1154.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Cegielska A., Moarefi I., Fanning E., Virshup D. M. T-antigen kinase inhibits simian virus 40 DNA replication by phosphorylation of intact T antigen on serines 120 and 123. J Virol. 1994 Jan;68(1):269–275. doi: 10.1128/jvi.68.1.269-275.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Cegielska A., Shaffer S., Derua R., Goris J., Virshup D. M. Different oligomeric forms of protein phosphatase 2A activate and inhibit simian virus 40 DNA replication. Mol Cell Biol. 1994 Jul;14(7):4616–4623. doi: 10.1128/mcb.14.7.4616. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Cegielska A., Virshup D. M. Control of simian virus 40 DNA replication by the HeLa cell nuclear kinase casein kinase I. Mol Cell Biol. 1993 Feb;13(2):1202–1211. doi: 10.1128/mcb.13.2.1202. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Chen C., Okayama H. High-efficiency transformation of mammalian cells by plasmid DNA. Mol Cell Biol. 1987 Aug;7(8):2745–2752. doi: 10.1128/mcb.7.8.2745. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Francke B., Eckhart W. Polyoma gene function required for viral DNA synthesis. Virology. 1973 Sep;55(1):127–135. doi: 10.1016/s0042-6822(73)81014-1. [DOI] [PubMed] [Google Scholar]
  8. Freund R., Bronson R. T., Benjamin T. L. Separation of immortalization from tumor induction with polyoma large T mutants that fail to bind the retinoblastoma gene product. Oncogene. 1992 Oct;7(10):1979–1987. [PubMed] [Google Scholar]
  9. Gjørup O. V., Rose P. E., Holman P. S., Bockus B. J., Schaffhausen B. S. Protein domains connect cell cycle stimulation directly to initiation of DNA replication. Proc Natl Acad Sci U S A. 1994 Dec 6;91(25):12125–12129. doi: 10.1073/pnas.91.25.12125. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Gorman C. M., Moffat L. F., Howard B. H. Recombinant genomes which express chloramphenicol acetyltransferase in mammalian cells. Mol Cell Biol. 1982 Sep;2(9):1044–1051. doi: 10.1128/mcb.2.9.1044. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Grässer F. A., Mann K., Walter G. Removal of serine phosphates from simian virus 40 large T antigen increases its ability to stimulate DNA replication in vitro but has no effect on ATPase and DNA binding. J Virol. 1987 Nov;61(11):3373–3380. doi: 10.1128/jvi.61.11.3373-3380.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Hassauer M., Scheidtmann K. H., Walter G. Mapping of phosphorylation sites in polyomavirus large T antigen. J Virol. 1986 Jun;58(3):805–816. doi: 10.1128/jvi.58.3.805-816.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Hirt B. Selective extraction of polyoma DNA from infected mouse cell cultures. J Mol Biol. 1967 Jun 14;26(2):365–369. doi: 10.1016/0022-2836(67)90307-5. [DOI] [PubMed] [Google Scholar]
  14. Holman P. S., Gjoerup O. V., Davin T., Schaffhausen B. S. Characterization of an immortalizing N-terminal domain of polyomavirus large T antigen. J Virol. 1994 Feb;68(2):668–673. doi: 10.1128/jvi.68.2.668-673.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Howes S. H., Bockus B. J., Schaffhausen B. S. Genetic analysis of polyomavirus large T nuclear localization: nuclear localization is required for productive association with pRb family members. J Virol. 1996 Jun;70(6):3581–3588. doi: 10.1128/jvi.70.6.3581-3588.1996. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Höss A., Moarefi I., Scheidtmann K. H., Cisek L. J., Corden J. L., Dornreiter I., Arthur A. K., Fanning E. Altered phosphorylation pattern of simian virus 40 T antigen expressed in insect cells by using a baculovirus vector. J Virol. 1990 Oct;64(10):4799–4807. doi: 10.1128/jvi.64.10.4799-4807.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Kellems R. E., Morhenn V. B., Pfendt E. A., Alt F. W., Schimke R. T. Polyoma virus and cyclic AMP-mediated control of dihydrofolate reductase mRNA abundance in methotrexate-resistant mouse fibroblasts. J Biol Chem. 1979 Jan 25;254(2):309–318. [PubMed] [Google Scholar]
  18. Kennelly P. J., Krebs E. G. Consensus sequences as substrate specificity determinants for protein kinases and protein phosphatases. J Biol Chem. 1991 Aug 25;266(24):15555–15558. [PubMed] [Google Scholar]
  19. Kern F. G., Pellegrini S., Cowie A., Basilico C. Regulation of polyomavirus late promoter activity by viral early proteins. J Virol. 1986 Oct;60(1):275–285. doi: 10.1128/jvi.60.1.275-285.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Kingston R. E., Cowie A., Morimoto R. I., Gwinn K. A. Binding of polyomavirus large T antigen to the human hsp70 promoter is not required for trans activation. Mol Cell Biol. 1986 Sep;6(9):3180–3190. doi: 10.1128/mcb.6.9.3180. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Klausing K., Scheidtmann K. H., Baumann E. A., Knippers R. Effects of in vitro dephosphorylation on DNA-binding and DNA helicase activities of simian virus 40 large tumor antigen. J Virol. 1988 Apr;62(4):1258–1265. doi: 10.1128/jvi.62.4.1258-1265.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
  23. Larose A., Dyson N., Sullivan M., Harlow E., Bastin M. Polyomavirus large T mutants affected in retinoblastoma protein binding are defective in immortalization. J Virol. 1991 May;65(5):2308–2313. doi: 10.1128/jvi.65.5.2308-2313.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Larose A., St-Onge L., Bastin M. Mutations in polyomavirus large T affecting immortalization of primary rat embryo fibroblasts. Virology. 1990 May;176(1):98–105. doi: 10.1016/0042-6822(90)90234-i. [DOI] [PubMed] [Google Scholar]
  25. Lentz M. R., Pak D., Mohr I., Botchan M. R. The E1 replication protein of bovine papillomavirus type 1 contains an extended nuclear localization signal that includes a p34cdc2 phosphorylation site. J Virol. 1993 Mar;67(3):1414–1423. doi: 10.1128/jvi.67.3.1414-1423.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Loeken M. R., Brady J. The adenovirus EIIA enhancer. Analysis of regulatory sequences and changes in binding activity of ATF and EIIF following adenovirus infection. J Biol Chem. 1989 Apr 15;264(11):6572–6579. [PubMed] [Google Scholar]
  27. Maione R., Fimia G. M., Amati P. Inhibition of in vitro myogenic differentiation by a polyomavirus early function. Oncogene. 1992 Jan;7(1):85–93. [PubMed] [Google Scholar]
  28. Maione R., Fimia G. M., Holman P., Schaffhausen B., Amati P. Retinoblastoma antioncogene is involved in the inhibition of myogenesis by polyomavirus large T antigen. Cell Growth Differ. 1994 Feb;5(2):231–237. [PubMed] [Google Scholar]
  29. McVey D., Brizuela L., Mohr I., Marshak D. R., Gluzman Y., Beach D. Phosphorylation of large tumour antigen by cdc2 stimulates SV40 DNA replication. Nature. 1989 Oct 12;341(6242):503–507. doi: 10.1038/341503a0. [DOI] [PubMed] [Google Scholar]
  30. McVey D., Ray S., Gluzman Y., Berger L., Wildeman A. G., Marshak D. R., Tegtmeyer P. cdc2 phosphorylation of threonine 124 activates the origin-unwinding functions of simian virus 40 T antigen. J Virol. 1993 Sep;67(9):5206–5215. doi: 10.1128/jvi.67.9.5206-5215.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  31. McVey D., Woelker B., Tegtmeyer P. Mechanisms of simian virus 40 T-antigen activation by phosphorylation of threonine 124. J Virol. 1996 Jun;70(6):3887–3893. doi: 10.1128/jvi.70.6.3887-3893.1996. [DOI] [PMC free article] [PubMed] [Google Scholar]
  32. Moarefi I. F., Small D., Gilbert I., Höpfner M., Randall S. K., Schneider C., Russo A. A., Ramsperger U., Arthur A. K., Stahl H. Mutation of the cyclin-dependent kinase phosphorylation site in simian virus 40 (SV40) large T antigen specifically blocks SV40 origin DNA unwinding. J Virol. 1993 Aug;67(8):4992–5002. doi: 10.1128/jvi.67.8.4992-5002.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. Mohr I. J., Stillman B., Gluzman Y. Regulation of SV40 DNA replication by phosphorylation of T antigen. EMBO J. 1987 Jan;6(1):153–160. doi: 10.1002/j.1460-2075.1987.tb04733.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Mudrak I., Ogris E., Rotheneder H., Wintersberger E. Coordinated trans activation of DNA synthesis- and precursor-producing enzymes by polyomavirus large T antigen through interaction with the retinoblastoma protein. Mol Cell Biol. 1994 Mar;14(3):1886–1892. doi: 10.1128/mcb.14.3.1886. [DOI] [PMC free article] [PubMed] [Google Scholar]
  35. Ogris E., Mudrak I., Wintersberger E. Distinct amounts of polyomavirus large T antigen are required for different functions of the protein. Oncogene. 1993 May;8(5):1277–1283. [PubMed] [Google Scholar]
  36. Peden K. W., Pipas J. M., Pearson-White S., Nathans D. Isolation of mutants of an animal virus in bacteria. Science. 1980 Sep 19;209(4463):1392–1396. doi: 10.1126/science.6251547. [DOI] [PubMed] [Google Scholar]
  37. Rassoulzadegan M., Naghashfar Z., Cowie A., Carr A., Grisoni M., Kamen R., Cuzin F. Expression of the large T protein of polyoma virus promotes the establishment in culture of "normal" rodent fibroblast cell lines. Proc Natl Acad Sci U S A. 1983 Jul;80(14):4354–4358. doi: 10.1073/pnas.80.14.4354. [DOI] [PMC free article] [PubMed] [Google Scholar]
  38. Richardson W. D., Roberts B. L., Smith A. E. Nuclear location signals in polyoma virus large-T. Cell. 1986 Jan 17;44(1):77–85. doi: 10.1016/0092-8674(86)90486-1. [DOI] [PubMed] [Google Scholar]
  39. Rose P. E., Schaffhausen B. S. Zinc-binding and protein-protein interactions mediated by the polyomavirus large T antigen zinc finger. J Virol. 1995 May;69(5):2842–2849. doi: 10.1128/jvi.69.5.2842-2849.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
  40. 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]
  41. Scheidtmann K. H., Virshup D. M., Kelly T. J. Protein phosphatase 2A dephosphorylates simian virus 40 large T antigen specifically at residues involved in regulation of DNA-binding activity. J Virol. 1991 Apr;65(4):2098–2101. doi: 10.1128/jvi.65.4.2098-2101.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  42. Schlegel R., Benjamin T. L. Cellular alterations dependent upon the polyoma virus Hr-t function: separation of mitogenic from transforming capacities. Cell. 1978 Jul;14(3):587–599. doi: 10.1016/0092-8674(78)90244-1. [DOI] [PubMed] [Google Scholar]
  43. Schneider J., Fanning E. Mutations in the phosphorylation sites of simian virus 40 (SV40) T antigen alter its origin DNA-binding specificity for sites I or II and affect SV40 DNA replication activity. J Virol. 1988 May;62(5):1598–1605. doi: 10.1128/jvi.62.5.1598-1605.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  44. Simmons D. T., Chou W., Rodgers K. Phosphorylation downregulates the DNA-binding activity of simian virus 40 T antigen. J Virol. 1986 Dec;60(3):888–894. doi: 10.1128/jvi.60.3.888-894.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
  45. Sullivan S., Wong T. W. A manual sequencing method for identification of phosphorylated amino acids in phosphopeptides. Anal Biochem. 1991 Aug 15;197(1):65–68. doi: 10.1016/0003-2697(91)90356-x. [DOI] [PubMed] [Google Scholar]
  46. Towbin H., Staehelin T., Gordon J. Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets: procedure and some applications. Proc Natl Acad Sci U S A. 1979 Sep;76(9):4350–4354. doi: 10.1073/pnas.76.9.4350. [DOI] [PMC free article] [PubMed] [Google Scholar]
  47. Virshup D. M., Kauffman M. G., Kelly T. J. Activation of SV40 DNA replication in vitro by cellular protein phosphatase 2A. EMBO J. 1989 Dec 1;8(12):3891–3898. doi: 10.1002/j.1460-2075.1989.tb08568.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  48. Virshup D. M., Kelly T. J. Purification of replication protein C, a cellular protein involved in the initial stages of simian virus 40 DNA replication in vitro. Proc Natl Acad Sci U S A. 1989 May;86(10):3584–3588. doi: 10.1073/pnas.86.10.3584. [DOI] [PMC free article] [PubMed] [Google Scholar]
  49. Wang E. H., Bhattacharyya S., Prives C. The replication functions of polyomavirus large tumor antigen are regulated by phosphorylation. J Virol. 1993 Nov;67(11):6788–6796. doi: 10.1128/jvi.67.11.6788-6796.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  50. Weichselbraun I., Haider G., Wintersberger E. Optimal replication of plasmids carrying polyomavirus origin regions requires two high-affinity binding sites for large T antigen. J Virol. 1989 Feb;63(2):961–964. doi: 10.1128/jvi.63.2.961-964.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Journal of Virology are provided here courtesy of American Society for Microbiology (ASM)

RESOURCES