Activation of the polyomavirus enhancer by a murine activator protein 1 (AP1) homolog and two contiguous proteins - PubMed (original) (raw)

Activation of the polyomavirus enhancer by a murine activator protein 1 (AP1) homolog and two contiguous proteins

M E Martin et al. Proc Natl Acad Sci U S A. 1988 Aug.

Abstract

The polyomavirus enhancer is composed of multiple DNA sequence elements serving as binding sites for proteins present in mouse nuclear extracts that activate transcription and DNA replication. We have identified three such proteins and their binding sites and correlate them with enhancer function. Mutation of nucleotide (nt) 5140 in the enhancer alters the binding site (TGACTAA, nt 5139-5145) for polyomavirus enhancer A binding protein 1 (PEA1), a murine homolog of the human transcription factor activator protein 1 (AP1). This mutation simultaneously reduces polyomavirus transcription and DNA replication. Reversion of this mutation simultaneously restores binding of PEA1 and both DNA replication and transcription. Binding of a second protein, PEA2, adjacent to the PEA1 site at nt 5147-5155 is enhanced by PEA1 binding, suggesting that these proteins interact. A third protein, PEA3, binds to the sequence AGGAAG (nt 5133-5138) adjacent to the PEA1 binding site; integrity of this late-proximal PEA3 binding site or an additional early-proximal site (nt 5228-5233) is important for enhancer function. We correlate binding of PEA1 and PEA2 with the induction of a DNase I-hypersensitive site in polyomavirus minichromosomes isolated from mouse fibroblasts.

PubMed Disclaimer

Similar articles

Cited by

References

    1. Cell. 1981 Sep;25(3):651-8 - PubMed
    1. Nucleic Acids Res. 1981 Jul 10;9(13):3047-60 - PubMed
    1. Proc Natl Acad Sci U S A. 1982 Mar;79(5):1479-83 - PubMed
    1. J Mol Biol. 1982 Nov 15;161(4):533-50 - PubMed
    1. Proc Natl Acad Sci U S A. 1983 Jun;80(12):3613-7 - PubMed

Publication types

MeSH terms

Substances

LinkOut - more resources