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Published on: September 17, 2012
Regulation of the Pcl7-Pho85 cyclin-cdk complex by Pho81
1Eukaryotic Transcription Laboratory, Marie Curie Research Institute, The Chart, Oxted, Surrey RH8 OTL, UK.
Molecular Microbiology
|November 9, 2000
Summary
The Pho85 cyclin-dependent kinase (cdk) interacts with Pcl7, a Pho80-like protein. This complex
Area of Science:
- * Molecular and Cellular Biology
- * Yeast Genetics
- * Biochemistry
Background:
- * Saccharomyces cerevisiae Pho85 cyclin-dependent kinase (cdk) regulates gene expression and metabolism.
- * Pho85 interacts with cyclins Pho80 and Pho80-like proteins (Pcls) to modulate its activity.
- * Pho85 deletion leads to pleiotropic effects including altered carbon source utilization and glycogen accumulation.
Purpose of the Study:
- * To investigate the role of the Pho80-like protein Pcl7 in complex formation with Pho85 cdk.
- * To elucidate the regulatory mechanisms of the Pcl7-Pho85 complex in response to phosphate availability.
- * To explore the involvement of Pcl7 in cell cycle progression and carbon source metabolism.
Main Methods:
- * Yeast genetics and molecular biology techniques.
- * Analysis of cyclin-cdk complex formation and activity.
- * Phenotypic characterization of yeast mutants.
Main Results:
- * Pcl7 forms a functional kinase complex with Pho85 cdk.
- * The Pcl7-Pho85 complex activity is inhibited by phosphate starvation and regulated by Pho81.
- * Pcl7 expression is cell cycle regulated, peaking in S-phase, and pcl7Delta mutants show carbon source utilization defects.
Conclusions:
- * Pho81 acts as a co-ordinator for both Pho80-Pho85 and Pcl7-Pho85 complexes in response to phosphate levels.
- * The Pcl7-Pho85 complex plays a role in cell cycle progression and carbon metabolism.
- * This study reveals novel regulatory interactions within the Pho85 cdk network.
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