Snf1/AMPK promotes S-phase entrance by controlling CLB5 transcription in budding yeast

Cell Cycle. 2010 Jun 1;9(11):2189-200. doi: 10.4161/cc.9.11.11847. Epub 2010 Jun 1.


The Saccharomyces cerevisiae Snf1 protein kinase has been reported to be required for adaptation to glucose limitation and for growth on non-fermentable carbon sources. Here we present novel findings indicating that Snf1, the key regulator of cellular energy, is also involved in yeast cell cycle control. The lack of Snf1 α-catalytic subunit down-regulates the growth rate and CLB5 expression, delaying Sld2 phosphorylation and G 1/S transition, in cells grown in 2%, but not in 5% glucose. A non-phosphorylatable Snf1 rescues the slow growth phenotype, whereas a wild type or a phosphomimetic mutant is required to rescue growth rate and the G 1/S delay. Using either Snf1 or Swi6 as a bait, a specific interaction of Snf1 with Swi6, the regulatory subunit of MBF, was detected. In conclusion, this report describes a previously unrecognized role for Snf1 in transcriptional modulation of the G 1 to S transition, differing from the reported AMPK role in controlling the G 1/S transition in multicellular eukaryotes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Cycle Proteins / metabolism
  • Cyclin B / genetics
  • Cyclin B / metabolism*
  • Down-Regulation
  • G1 Phase
  • Glucose / pharmacology
  • Mutation
  • Phosphorylation
  • Protein Subunits / metabolism
  • Protein-Serine-Threonine Kinases / genetics
  • Protein-Serine-Threonine Kinases / metabolism*
  • Protein-Serine-Threonine Kinases / physiology
  • S Phase
  • Saccharomyces cerevisiae / enzymology*
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Transcription Factors / metabolism
  • Transcription, Genetic


  • CLB5 protein, S cerevisiae
  • Cell Cycle Proteins
  • Cyclin B
  • Protein Subunits
  • SLD2 protein, S cerevisiae
  • SWI6 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • Transcription Factors
  • SNF1-related protein kinases
  • Protein-Serine-Threonine Kinases
  • Glucose