The histone deacetylase Hos2 forms an Hsp42-dependent cytoplasmic granule in quiescent yeast cells

Mol Biol Cell. 2012 Apr;23(7):1231-42. doi: 10.1091/mbc.E11-09-0752. Epub 2012 Feb 15.

Abstract

One of many physiological adjustments in quiescent cells is spatial regulation of specific proteins and RNA important for the entry to or exit from the stationary phase. By examining the localization of epigenetic-related proteins in Saccharomyces cerevisiae, we observed the formation of a reversible cytosolic "stationary-phase granule" (SPG) by Hos2, a nuclear histone deacetylase. In the stationary phase, hos2 mutants display reduced viability. Additionally, they exhibit a significant delay when recovering from stationary phase. Hos2 SPGs also contained Hst2, a Sir2 homologue, and several stress-related proteins, including Set3, Yca1, Hsp26, Hsp42, and some known components of stress granules. However, Hos2 SPG formation does not depend on the formation of stress granules or processing bodies. The absence or presence of glucose is sufficient to trigger assembly or disassembly of Hos2 SPGs. Among the identified components of Hos2 SPGs, Hsp42 is the first and last member observed in the Hos2 SPG assembly and disassembly processes. Hsp42 is also vital for the relocalization of the other components to Hos2 SPGs, suggesting that Hsp42 plays a central role in spatial regulation of proteins in quiescent cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actin Cytoskeleton / metabolism
  • Cytoplasmic Granules / metabolism
  • Epigenesis, Genetic
  • Genes, Fungal
  • Glucose / metabolism
  • Heat-Shock Proteins / chemistry
  • Heat-Shock Proteins / metabolism*
  • Heat-Shock Response
  • Histone Deacetylases / chemistry
  • Histone Deacetylases / genetics
  • Histone Deacetylases / metabolism*
  • Mutation
  • Protein Multimerization
  • Recombinant Fusion Proteins / chemistry
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Resting Phase, Cell Cycle
  • Saccharomyces cerevisiae / cytology
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / chemistry
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*

Substances

  • HSP26 protein, S cerevisiae
  • HSP42 protein, S cerevisiae
  • Heat-Shock Proteins
  • Recombinant Fusion Proteins
  • Saccharomyces cerevisiae Proteins
  • HOS2 protein, S cerevisiae
  • Set3 protein, S cerevisiae
  • Histone Deacetylases
  • Glucose