Activation of SV40 DNA replication in vitro by cellular protein phosphatase 2A.
Journal Article (Journal Article)
We have made use of the cell-free SV40 DNA replication system to identify and characterize cellular proteins required for efficient DNA synthesis. One such protein, replication protein C (RP-C), was shown to be involved with SV40 large T antigen in the early stages of viral DNA replication in vitro. We demonstrate here that RP-C is identical to the catalytic subunit of cellular protein phosphatase 2A (PP2Ac). The purified protein dephosphorylates specific phosphoamino acid residues in T antigen, consistent with the hypothesis that SV40 DNA replication is regulated by modulating the phosphorylation state of the viral initiator protein. We also show that purified RP-C/PP2Ac preferentially stimulates SV40 DNA replication in extracts from early G1 phase cells. This finding suggests that the activity of a cellular factor that influences the net phosphorylation state of T antigen is cell cycle dependent.
Full Text
Duke Authors
Cited Authors
- Virshup, DM; Kauffman, MG; Kelly, TJ
Published Date
- December 1, 1989
Published In
Volume / Issue
- 8 / 12
Start / End Page
- 3891 - 3898
PubMed ID
- 2555176
Pubmed Central ID
- PMC402079
International Standard Serial Number (ISSN)
- 0261-4189
Digital Object Identifier (DOI)
- 10.1002/j.1460-2075.1989.tb08568.x
Language
- eng
Conference Location
- England