The SNF1 kinase complex from Saccharomyces cerevisiae phosphorylates the transcriptional repressor protein Mig1p in vitro at four sites within or near regulatory domain 1

FEBS Lett. 1999 Jun 18;453(1-2):219-23. doi: 10.1016/s0014-5793(99)00725-5.


Mig1p is a zinc finger protein required for repression of glucose-regulated genes in budding yeast. On removal of medium glucose, gene repression is relieved via a mechanism that requires the SNF1 protein kinase complex. We show that Mig1p expressed as a glutathione-S-transferase fusion in bacteria is readily phosphorylated by the SNF1 kinase in vitro. Four phosphorylation sites were identified, i.e. Ser-222, Ser-278, Ser-311 and Ser-381. The latter three are exact matches to the recognition motif we previously defined for SNF1 and lie within regions shown to be required for SNF1-dependent derepression and nuclear-to-cytoplasmic translocation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aspartic Acid / genetics
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • Enzyme Repression
  • Gene Expression Regulation, Fungal
  • Glucose / metabolism
  • Glutamic Acid / genetics
  • Glutathione Transferase / genetics
  • Kluyveromyces / enzymology
  • Kluyveromyces / genetics
  • Mutagenesis, Site-Directed
  • Phosphorylation
  • Protein-Serine-Threonine Kinases / genetics
  • Protein-Serine-Threonine Kinases / metabolism*
  • Recombinant Fusion Proteins / metabolism
  • Regulatory Sequences, Nucleic Acid
  • Repressor Proteins / genetics
  • Repressor Proteins / metabolism*
  • Saccharomyces cerevisiae / enzymology*
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae Proteins
  • Serine / genetics
  • Substrate Specificity


  • DNA-Binding Proteins
  • MIG1 protein, S cerevisiae
  • Recombinant Fusion Proteins
  • Repressor Proteins
  • Saccharomyces cerevisiae Proteins
  • Aspartic Acid
  • Glutamic Acid
  • Serine
  • Glutathione Transferase
  • SNF1-related protein kinases
  • Protein-Serine-Threonine Kinases
  • Glucose