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
. 1993 Jun 1;90(11):5086-90.
doi: 10.1073/pnas.90.11.5086.

The E1 protein of bovine papilloma virus 1 is an ATP-dependent DNA helicase

L Yang  1 , I Mohr, E Fouts, D A Lim, M Nohaile, M Botchan
Affiliations

The E1 protein of bovine papilloma virus 1 is an ATP-dependent DNA helicase

L Yang et al. Proc Natl Acad Sci U S A. .

Abstract

For efficient DNA replication of papillomaviruses, only two viral-encoded proteins, E1 and E2, are required. Other proteins and factors are provided by the host cell. E2 is an enhancer of both transcription and replication and is known to help E1 bind cooperatively to the origin of DNA replication. E1 is sufficient for replication in extracts prepared from permissive cells, but the activity is enhanced by E2. Here we show that purified E1 can act as an ATP-dependent DNA helicase. To measure this activity, we have used strand displacement, unwinding of topologically constrained DNA, denaturation of duplex fragments, and electron microscopy. The ability of E1 to unwind circular DNA is found to be independent of origin-specific viral DNA sequences under a variety of experimental conditions. In unfractionated cellular extracts, E1-dependent viral DNA replication is origin-dependent, but at elevated E1 concentrations, replication can occur on non-origin-containing DNA templates. This conversion from an origin-dependent replication system to a nonspecific initiator system is discussed in the context of the current understanding of the initiation of chromosomal DNA replication.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. J Virol. 1992 Oct;66(10):5949-58 - PubMed
    1. Proc Natl Acad Sci U S A. 1992 Jul 1;89(13):5799-803 - PubMed
    1. Cell. 1984 Aug;38(1):55-64 - PubMed
    1. Proc Natl Acad Sci U S A. 1987 Jun;84(11):3643-7 - PubMed
    1. Mol Cell Biol. 1988 Nov;8(11):4765-72 - PubMed

Publication types

MeSH terms

LinkOut - more resources