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. 1992 Mar;66(3):1489–1494. doi: 10.1128/jvi.66.3.1489-1494.1992

Involvement of simian virus 40 (SV40) small t antigen in trans activation of SV40 early and late promoters.

I Bikel 1, M R Loeken 1
PMCID: PMC240874  PMID: 1310761

Abstract

We have previously found that simian virus 40 (SV40) small t antigen (small t) can trans activate the E2A and VA-I genes of adenovirus in plasmid DNA-transfected cells (M. R. Loeken, I. Bikel, D. M. Livingston, and J. Brady, Cell 55:1171-1177, 1988). To determine whether trans activation by small t might be involved in the SV40 productive infection cycle, we examined the effects of cotransfecting plasmids encoding small t with plasmids containing the chloramphenicol acetyltransferase (CAT) gene linked to the SV40 early or late promoter. Small t increased three- to fivefold the expression of a CAT plasmid linked to the SV40 early promoter and enhancer. Small t expression had no effect by itself on CAT activity directed by the SV40 late promoter, but small t enhanced the effect of a suboptimal concentration of a plasmid expressing large T up to 10-fold. When the concentration of the plasmid expressing large T was increased to a level at which large T alone stimulated the late promoter ninefold, the enhancement by small t was only twofold. The effects of small t on both the SV40 early and late promoters depended on sequences within the small t-unique domain, since a plasmid expressing only the first 82 amino acids common to both large T and small t was inactive. The effects of small t on early- and late-promoter-directed CAT enzyme activity was reflected in increased CAT mRNA as measured by S1 analysis. These results suggest that SV40 small t may play a role in viral infection by increasing transcription from the early promoter and from the late promoter at times when large T levels are low.

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Selected References

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  1. Bikel I., Mamon H., Brown E. L., Boltax J., Agha M., Livingston D. M. The t-unique coding domain is important to the transformation maintenance function of the simian virus 40 small t antigen. Mol Cell Biol. 1986 Apr;6(4):1172–1178. doi: 10.1128/mcb.6.4.1172. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Bikel I., Montano X., Agha M. E., Brown M., McCormack M., Boltax J., Livingston D. M. SV40 small t antigen enhances the transformation activity of limiting concentrations of SV40 large T antigen. Cell. 1987 Jan 30;48(2):321–330. doi: 10.1016/0092-8674(87)90435-1. [DOI] [PubMed] [Google Scholar]
  3. Brady J., Bolen J. B., Radonovich M., Salzman N., Khoury G. Stimulation of simian virus 40 late gene expression by simian virus 40 tumor antigen. Proc Natl Acad Sci U S A. 1984 Apr;81(7):2040–2044. doi: 10.1073/pnas.81.7.2040. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Brown M., McCormack M., Zinn K. G., Farrell M. P., Bikel I., Livingston D. M. A recombinant murine retrovirus for simian virus 40 large T cDNA transforms mouse fibroblasts to anchorage-independent growth. J Virol. 1986 Oct;60(1):290–293. doi: 10.1128/jvi.60.1.290-293.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Buchman A. R., Fromm M., Berg P. Complex regulation of simian virus 40 early-region transcription from different overlapping promoters. Mol Cell Biol. 1984 Sep;4(9):1900–1914. doi: 10.1128/mcb.4.9.1900. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Chomczynski P., Sacchi N. Single-step method of RNA isolation by acid guanidinium thiocyanate-phenol-chloroform extraction. Anal Biochem. 1987 Apr;162(1):156–159. doi: 10.1006/abio.1987.9999. [DOI] [PubMed] [Google Scholar]
  7. Gallo G. J., Gilinger G., Alwine J. C. Simian virus 40 T antigen alters the binding characteristics of specific simian DNA-binding factors. Mol Cell Biol. 1988 Apr;8(4):1648–1656. doi: 10.1128/mcb.8.4.1648. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Gallo G. J., Gruda M. C., Manuppello J. R., Alwine J. C. Activity of simian DNA-binding factors is altered in the presence of simian virus 40 (SV40) early proteins: characterization of factors binding to elements involved in activation of the SV40 late promoter. J Virol. 1990 Jan;64(1):173–184. doi: 10.1128/jvi.64.1.173-184.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Ghosh P. K., Lebowitz P. Simian virus 40 early mRNA's contain multiple 5' termini upstream and downstream from a Hogness-Goldberg sequence; a shift in 5' termini during the lytic cycle is mediated by large T antigen. J Virol. 1981 Oct;40(1):224–240. doi: 10.1128/jvi.40.1.224-240.1981. [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. Hansen U., Tenen D. G., Livingston D. M., Sharp P. A. T antigen repression of SV40 early transcription from two promoters. Cell. 1981 Dec;27(3 Pt 2):603–613. doi: 10.1016/0092-8674(81)90402-5. [DOI] [PubMed] [Google Scholar]
  12. Harlow E., Crawford L. V., Pim D. C., Williamson N. M. Monoclonal antibodies specific for simian virus 40 tumor antigens. J Virol. 1981 Sep;39(3):861–869. doi: 10.1128/jvi.39.3.861-869.1981. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Keller J. M., Alwine J. C. Activation of the SV40 late promoter: direct effects of T antigen in the absence of viral DNA replication. Cell. 1984 Feb;36(2):381–389. doi: 10.1016/0092-8674(84)90231-9. [DOI] [PubMed] [Google Scholar]
  14. Keller J. M., Alwine J. C. Analysis of an activatable promoter: sequences in the simian virus 40 late promoter required for T-antigen-mediated trans activation. Mol Cell Biol. 1985 Aug;5(8):1859–1869. doi: 10.1128/mcb.5.8.1859. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Khalili K., Brady J., Khoury G. Translational regulation of SV40 early mRNA defines a new viral protein. Cell. 1987 Feb 27;48(4):639–645. doi: 10.1016/0092-8674(87)90242-x. [DOI] [PubMed] [Google Scholar]
  16. Lawson R., Cohen P., Lane D. P. Simian virus 40 large T-antigen-dependent DNA replication is activated by protein phosphatase 2A in vitro. J Virol. 1990 May;64(5):2380–2383. doi: 10.1128/jvi.64.5.2380-2383.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Livingston D. M., Bradley M. K. The simian virus 40 large T antigen. A lot packed into a little. Mol Biol Med. 1987 Apr;4(2):63–80. [PubMed] [Google Scholar]
  18. Loeken M. R., Khoury G., Brady J. Stimulation of the adenovirus E2 promoter by simian virus 40 T antigen or E1A occurs by different mechanisms. Mol Cell Biol. 1986 Jun;6(6):2020–2026. doi: 10.1128/mcb.6.6.2020. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Loeken M., Bikel I., Livingston D. M., Brady J. trans-activation of RNA polymerase II and III promoters by SV40 small t antigen. Cell. 1988 Dec 23;55(6):1171–1177. doi: 10.1016/0092-8674(88)90261-9. [DOI] [PubMed] [Google Scholar]
  20. Martin R. G., Setlow V. P., Edwards C. A., Vembu D. The roles of the simian virus 40 tumor antigens in transformation of Chinese hamster lung cells. Cell. 1979 Jul;17(3):635–643. doi: 10.1016/0092-8674(79)90271-x. [DOI] [PubMed] [Google Scholar]
  21. 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]
  22. Pallas D. C., Shahrik L. K., Martin B. L., Jaspers S., Miller T. B., Brautigan D. L., Roberts T. M. Polyoma small and middle T antigens and SV40 small t antigen form stable complexes with protein phosphatase 2A. Cell. 1990 Jan 12;60(1):167–176. doi: 10.1016/0092-8674(90)90726-u. [DOI] [PubMed] [Google Scholar]
  23. Saffer J. D., Jackson S. P., Thurston S. J. SV40 stimulates expression of the transacting factor Sp1 at the mRNA level. Genes Dev. 1990 Apr;4(4):659–666. doi: 10.1101/gad.4.4.659. [DOI] [PubMed] [Google Scholar]
  24. Scheidtmann K. H., Mumby M. C., Rundell K., Walter G. Dephosphorylation of simian virus 40 large-T antigen and p53 protein by protein phosphatase 2A: inhibition by small-t antigen. Mol Cell Biol. 1991 Apr;11(4):1996–2003. doi: 10.1128/mcb.11.4.1996. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. 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]
  26. Shenk T. E., Carbon J., Berg P. Construction and analysis of viable deletion mutants of simian virus 40. J Virol. 1976 May;18(2):664–671. doi: 10.1128/jvi.18.2.664-671.1976. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Topp W. C. Variable defectiveness for lytic growth of the dl 54/59 mutants of simian virus 40. J Virol. 1980 Mar;33(3):1208–1210. doi: 10.1128/jvi.33.3.1208-1210.1980. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. 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]
  29. Walter G., Ruediger R., Slaughter C., Mumby M. Association of protein phosphatase 2A with polyoma virus medium tumor antigen. Proc Natl Acad Sci U S A. 1990 Apr;87(7):2521–2525. doi: 10.1073/pnas.87.7.2521. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. Wildeman A. G. Transactivation of both early and late simian virus 40 promoters by large tumor antigen does not require nuclear localization of the protein. Proc Natl Acad Sci U S A. 1989 Apr;86(7):2123–2127. doi: 10.1073/pnas.86.7.2123. [DOI] [PMC free article] [PubMed] [Google Scholar]
  31. Zhu J. Y., Rice P. W., Chamberlain M., Cole C. N. Mapping the transcriptional transactivation function of simian virus 40 large T antigen. J Virol. 1991 Jun;65(6):2778–2790. doi: 10.1128/jvi.65.6.2778-2790.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]

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