Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1992 Jul;66(7):4591-6.
doi: 10.1128/JVI.66.7.4591-4596.1992.

Activation of simian virus 40 transcription in vitro by T antigen

J Coulombe  1 , L Berger, D B Smith, R K Hehl, A G Wildeman
Affiliations

Activation of simian virus 40 transcription in vitro by T antigen

J Coulombe et al. J Virol. 1992 Jul.

Abstract

Simian virus 40 is repressed when the viral early gene product large tumor antigen (TAg) binds to specific sites within the viral origin and DNA replication ensues. Late transcription is activated by TAg, even in the absence of viral DNA replication. We show here that TAg produced in human 293 cells can selectively activate Simian virus 40 transcription in a cell-free system. In the absence of DNA binding by TAg, early and late transcription are both activated, as they are in vivo, suggesting that the effect might be mediated by a cellular component(s) utilized by both the early and late promoters. When TAg binds to the viral origin of replication, early transcription is repressed but the late promoter activation is unaffected. Various preparations of TAg differed in their activities, with some able both to bind DNA and to activate transcription and others able to do only one or the other. Since these variations might be explained by variable amounts of associated factors that copurified with TAg, we asked whether a bacterially derived protein could regulate transcription. An NH2-terminal 272-amino-acid fragment of TAg, produced in Escherichia coli as a glutathione S-transferase fusion protein, retains the ability to activate transcription in vitro, similar to that of the full-length protein. Structural features of this region that might be important are discussed.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Annu Rev Genet. 1989;23:141-61 - PubMed
    1. Cell. 1989 Jan 13;56(1):57-65 - PubMed
    1. Proc Natl Acad Sci U S A. 1989 Sep;86(17):6479-83 - PubMed
    1. Nature. 1985 Sep 12-18;317(6033):169-71 - PubMed
    1. Virology. 1985 Jul 15;144(1):88-100 - PubMed

Publication types

Substances

LinkOut - more resources