The yeast Mig1 transcriptional repressor is dephosphorylated by glucose-dependent and -independent mechanisms

FEMS Microbiol Lett. 2017 Aug 1;364(14). doi: 10.1093/femsle/fnx133.

Abstract

A yeast Saccharomyces cerevisiae Snf1 kinase, an analog of mammalian AMPK, regulates glucose derepression of genes required for utilization of alternative carbon sources through the transcriptional repressor Mig1. It has been suggested that the Glc7-Reg1 phosphatase dephosphorylates Mig1. Here we report that Mig1 is dephosphorylated by Glc7-Reg1 in an apparently glucose-dependent mechanism but also by a mechanism independent of glucose and Glc7-Reg1. In addition to serine/threonine phosphatases another process including tyrosine phosphorylation seems crucial for Mig1 regulation. Taken together, Mig1 dephosphorylation appears to be controlled in a complex manner, in line with the importance for rapid and sensitive regulation upon altered glucose concentrations in the growth medium.

Keywords: Mig1; dephosphorylation; glucose repression; inhibitors; phosphatases.

MeSH terms

  • Gene Expression Regulation, Fungal
  • Glucose / metabolism*
  • Phosphoprotein Phosphatases / metabolism
  • Phosphorylation
  • Protein Phosphatase 1 / genetics
  • Protein Phosphatase 1 / metabolism
  • Repressor Proteins / genetics
  • Repressor Proteins / metabolism*
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Vanadates / pharmacology

Substances

  • MIG1 protein, S cerevisiae
  • Repressor Proteins
  • Saccharomyces cerevisiae Proteins
  • Vanadates
  • GLC7 protein, S cerevisiae
  • Phosphoprotein Phosphatases
  • Protein Phosphatase 1
  • REG1 protein, S cerevisiae
  • Glucose