Mapping the interaction of Snf1 with TORC1 in Saccharomyces cerevisiae

Mol Syst Biol. 2011 Nov 8:7:545. doi: 10.1038/msb.2011.80.

Abstract

Nutrient sensing and coordination of metabolic pathways are crucial functions for all living cells, but details of the coordination under different environmental conditions remain elusive. We therefore undertook a systems biology approach to investigate the interactions between the Snf1 and the target of rapamycin complex 1 (TORC1) in Saccharomyces cerevisiae. We show that Snf1 regulates a much broader range of biological processes compared with TORC1 under both glucose- and ammonium-limited conditions. We also find that Snf1 has a role in upregulating the NADP(+)-dependent glutamate dehydrogenase (encoded by GDH3) under derepressing condition, and therefore may also have a role in ammonium assimilation and amino-acid biosynthesis, which can be considered as a convergence of Snf1 and TORC1 pathways. In addition to the accepted role of Snf1 in regulating fatty acid (FA) metabolism, we show that TORC1 also regulates FA metabolism, likely through modulating the peroxisome and β-oxidation. Finally, we conclude that direct interactions between Snf1 and TORC1 pathways are unlikely under nutrient-limited conditions and propose that TORC1 is repressed in a manner that is independent of Snf1.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acids / biosynthesis
  • Fatty Acids / metabolism
  • Gene Expression Regulation, Fungal
  • Glutamate Dehydrogenase / biosynthesis
  • Protein Serine-Threonine Kinases / genetics
  • Protein Serine-Threonine Kinases / metabolism*
  • Saccharomyces cerevisiae / cytology
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Sirolimus / metabolism
  • Systems Biology / methods
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*
  • Transcriptome

Substances

  • Amino Acids
  • Fatty Acids
  • Saccharomyces cerevisiae Proteins
  • TORC1 protein complex, S cerevisiae
  • Transcription Factors
  • Glutamate Dehydrogenase
  • SNF1-related protein kinases
  • Protein Serine-Threonine Kinases
  • Sirolimus