Preparing your results

Our searching services are busy right now. Your search will reload in five seconds.

X
Forgot Password

If you have forgotten your password you can enter your email here and get a temporary password sent to your email.

Identification of Clb2 residues required for Swe1 regulation of Clb2-Cdc28 in Saccharomyces cerevisiae.

Genetics | Jun 18, 2008

http://www.ncbi.nlm.nih.gov/pubmed/18558651

Wee1 kinases regulate the cell cycle through inhibitory phosphorylation of cyclin-dependent kinases (CDKs). Eukaryotic cells express multiple CDKs, each having a kinase subunit (Cdk) and a regulatory "cyclin" subunit that function at different stages of the cell cycle to regulate distinct processes. The cyclin imparts specificity to CDK-substrate interactions and also determines whether a particular CDK is subject to Wee1 regulation. Saccharomyces Wee1 (Swe1) inhibits Cdc28 (Cdk1) associated with the mitotic cyclin, Clb2, but not with the G(1) (Cln1, -2, and -3) or the S-phase (Clb5 and -6) cyclins. Here, we show that this specificity depends on two amino acids associated with a conserved "hydrophobic patch" (HP) motif on the cyclin surface, which mediates specificity of CDK-substrate interactions. Mutation of Clb2 residues N260 and K270 largely abrogates Clb2-Cdc28 regulation by Swe1, and reciprocal mutation of the corresponding residues in Clb5 can subject Clb5-Cdc28 to regulation by Swe1. Swe1 phosphorylation by Clb2-Cdc28, which is thought to activate Swe1 kinase, depends on N260 and K270, suggesting that specific regulation of Clb2-Cdc28 by Swe1 derives from the specific ability of Clb2 to target Swe1 for activating phosphorylation. The stable association of Swe1 with Clb2-Cdc28 also depends on these residues, suggesting that Swe1 may competitively inhibit Clb2-Cdc28 interactions with substrates, in addition to its well-known function as a regulator of CDK activity through tyrosine phosphorylation.

Pubmed ID: 18558651 RIS Download

Mesh terms: Amino Acid Sequence | CDC28 Protein Kinase, S cerevisiae | Cell Cycle | Cell Cycle Proteins | Cyclin B | Genes, Fungal | Hydrophobic and Hydrophilic Interactions | Molecular Sequence Data | Multiprotein Complexes | Phosphorylation | Protein Subunits | Protein-Tyrosine Kinases | Saccharomyces cerevisiae | Saccharomyces cerevisiae Proteins | Sequence Homology, Amino Acid | Substrate Specificity | Tyrosine

Research resources used in this publication

None found

Research tools detected in this publication

None found

Data used in this publication

None found

Associated grants

  • Agency: NIGMS NIH HHS, Id: GM-65494

Publication data is provided by the National Library of Medicine ® and PubMed ®. Data is retrieved from PubMed ® on a weekly schedule. For terms and conditions see the National Library of Medicine Terms and Conditions.