Degradation of the Saccharomyces cerevisiae mating-type regulator α1: Genetic dissection of Cis-determinants and trans-acting pathways

Christina E. Nixon, Alexander J. Wilcox, Jeffrey D. Laney

Research output: Contribution to journalArticlepeer-review

15 Scopus citations

Abstract

Mating phenotype in the yeast Saccharomyces cerevisiae is a dynamic trait, and efficient transitions between alternate haploid cell types allow the organism to access the advantageous diploid form. Mating identity is determined by cell type-specific transcriptional regulators, but these factors must be rapidly removed upon mating-type switching to allow the master regulators of the alternate state to establish a new gene expression program. Targeted proteolysis by the ubiquitin-proteasome system is a commonly employed strategy to quickly disassemble regulatory networks, and yeast use this approach to evoke efficient switching from the α to the a phenotype by ensuring the rapid removal of the α2 transcriptional repressor. Transition to the a cell phenotype, however, also requires the inactivation of the α1 transcriptional activator, but the mechanism by which this occurs is currently unknown. Here, we report a central role for the ubiquitin-proteasome system in α1 inactivation. The α1 protein is constitutively short lived and targeted for rapid turnover by multiple ubiquitin-conjugation pathways. Intriguingly, the α-domain, a conserved region of unknown function, acts as a degradation signal for a pathway defined by the SUMO-targeted ligase Slx5-Slx8, which has also been implicated in the rapid destruction of α2. Our observations suggest coordinate regulation in the turnover of two master regulatory transcription factors ensures a rapid mating-type switch.

Original languageEnglish (US)
Pages (from-to)497-511
Number of pages15
JournalGenetics
Volume185
Issue number2
DOIs
StatePublished - Jun 2010

ASJC Scopus subject areas

  • Genetics

Fingerprint

Dive into the research topics of 'Degradation of the Saccharomyces cerevisiae mating-type regulator α1: Genetic dissection of Cis-determinants and trans-acting pathways'. Together they form a unique fingerprint.

Cite this