Glc8 is a glucose-repressible activator of Glc7 protein phosphatase-1

Arch Biochem Biophys. 2002 Aug 1;404(1):71-9. doi: 10.1016/s0003-9861(02)00231-x.

Abstract

Regulation of Glc7 type 1 protein phosphatase stability and activity was studied in budding yeast. We found that the Glc7 protein has a half-life of over 180min, which is sufficient for several generations. Glc7 protein stability was constant during the cell cycle and in batch culture growth. Furthermore, deletion of regulatory subunit Gac1, Reg1, Reg2, Sds22, or Glc8 had no influence on Glc7 protein half-life. The activity of Glc7 assayed as okadaic acid-resistant phosphorylase phosphatase activity was constant during the cell cycle. Deletion of the aforementioned regulatory subunits revealed that only Glc8 deletion had a significant effect in reducing Glc7 activity. Glc7 activity was induced during stationary phase in a Glc8-dependent manner. In addition, extracellular glucose repressed the induction of Glc7 activity. These results are consistent with glucose repression of Glc8 expression and favor the role of Glc8 as a major Glc7 activator.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Cell Cycle
  • Enzyme Activation
  • Enzyme Inhibitors*
  • Enzyme Stability
  • Fungal Proteins / antagonists & inhibitors
  • Fungal Proteins / chemistry
  • Fungal Proteins / genetics
  • Fungal Proteins / metabolism*
  • Gene Deletion
  • Genes, Fungal
  • Glucose / pharmacology
  • Mutation
  • Phosphoprotein Phosphatases / antagonists & inhibitors
  • Phosphoprotein Phosphatases / chemistry
  • Phosphoprotein Phosphatases / genetics
  • Phosphoprotein Phosphatases / metabolism*
  • Plasmids / genetics
  • Protein Phosphatase 1
  • Protein Subunits
  • Saccharomyces cerevisiae / drug effects
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism
  • Saccharomyces cerevisiae Proteins / antagonists & inhibitors
  • Saccharomyces cerevisiae Proteins / chemistry
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*

Substances

  • Enzyme Inhibitors
  • Fungal Proteins
  • GLC8 protein, S cerevisiae
  • Protein Subunits
  • Saccharomyces cerevisiae Proteins
  • Phosphoprotein Phosphatases
  • Protein Phosphatase 1
  • Glucose