Coverley, D., Laman, H. and Laskey, R.A. (2002) Distinct roles for cyclins E and A during DNA replication complex assembly and activation. Nature Cell Biology, 4 (7). pp. 523-528. ISSN 1465-7392
Abstract
Initiation of DNA replication is regulated by cyclin-dependent protein kinase 2 (Cdk2) in association with two different regulatory subunits, cyclin A and cyclin E (reviewed in ref. 1). But why two different cyclins are required and why their order of activation is tightly regulated are unknown. Using a cell-free system for initiation of DNA replication that is based on G1 nuclei, G1 cytosol and recombinant proteins, we find that cyclins E and A have specialized roles during the transition from G0 to S phase. Cyclin E stimulates replication complex assembly by cooperating with Cdc6, to make G1 nuclei competent to replicate in vitro. Cyclin A has two separable functions: it activates DNA synthesis by replication complexes that are already assembled, and it inhibits the assembly of new complexes. Thus, cyclin E opens a 'window of opportunity' for replication complex assembly that is closed by cyclin A. The dual functions of cyclin A ensure that the assembly phase (G1) ends before DNA synthesis (S) begins, thereby preventing re-initiation until the next cell cycle.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Dates: |
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Institution: | The University of York |
Academic Units: | The University of York > Faculty of Sciences (York) > Biology (York) |
Depositing User: | York RAE Import |
Date Deposited: | 20 Mar 2009 11:52 |
Last Modified: | 20 Mar 2009 11:52 |
Published Version: | http://dx.doi.org/10.1038/ncb813 |
Status: | Published |
Publisher: | Nature Publishing Group |
Identification Number: | 10.1038/ncb813 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:7054 |