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.

SCFCdc4 enables mating type switching in yeast by cyclin-dependent kinase-mediated elimination of the Ash1 transcriptional repressor.

http://www.ncbi.nlm.nih.gov/pubmed/21098119

In the budding yeast Saccharomyces cerevisiae, mother cells switch mating types between a and α forms, whereas daughter cells do not. This developmental asymmetry arises because the expression of the HO endonuclease, which initiates the interconversion of a and α mating type cassettes, is extinguished by the daughter-specific Ash1 transcriptional repressor. When daughters become mothers in the subsequent cell cycle, Ash1 must be eliminated to enable a new developmental state. Here, we report that the ubiquitin ligase SCF(Cdc4) mediates the phosphorylation-dependent elimination of Ash1. The inactivation of SCF(Cdc4) stabilizes Ash1 in vivo, and consistently, Ash1 binds to and is ubiquitinated by SCF(Cdc4) in a phosphorylation-dependent manner in vitro. The mutation of a critical in vivo cyclin-dependent kinase (CDK) phosphorylation site (Thr290) on Ash1 reduces its ubiquitination and rate of degradation in vivo and decreases the frequency of mating type switching. Ash1 associates with active Cdc28 kinase in vivo and is targeted to SCF(Cdc4) in a Cdc28-dependent fashion in vivo and in vitro. Ash1 recognition by Cdc4 appears to be mediated by at least three phosphorylation sites that form two redundant diphosphorylated degrons. The phosphorylation-dependent elimination of Ash1 by the ubiquitin-proteasome system thus underpins developmental asymmetry in budding yeast.

Pubmed ID: 21098119 RIS Download

Mesh terms: Amino Acid Sequence | CDC28 Protein Kinase, S cerevisiae | Cell Cycle | Cell Cycle Proteins | Cyclin-Dependent Kinases | F-Box Proteins | Gene Silencing | Genes, Mating Type, Fungal | Molecular Sequence Data | Phosphorylation | Phosphothreonine | Protein Binding | Protein Processing, Post-Translational | Protein Stability | Protein Transport | Repressor Proteins | Saccharomyces cerevisiae | Saccharomyces cerevisiae Proteins | Transcription, Genetic | Ubiquitin-Protein Ligases | Ubiquitination

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: Biotechnology and Biological Sciences Research Council, Id: BB/D019621/1
  • Agency: Canadian Institutes of Health Research, Id:

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.