Hos1 deacetylates Smc3 to close the cohesin acetylation cycle

Mol Cell. 2010 Sep 10;39(5):677-88. doi: 10.1016/j.molcel.2010.08.009.


Cohesion between sister chromatids is mediated by the chromosomal cohesin complex. In budding yeast, cohesin is loaded onto chromosomes during the G1 phase of the cell cycle. During S phase, the replication fork-associated acetyltransferase Eco1 acetylates the cohesin subunit Smc3 to promote the establishment of sister chromatid cohesion. At the time of anaphase, Smc3 loses its acetylation again, but the Smc3 deacetylase and the possible importance of Smc3 deacetylation are unknown. Here, we show that the class I histone deacetylase family member Hos1 is responsible for Smc3 deacetylation. Cohesin is protected from deacetylation while bound to chromosomes but is deacetylated as soon as it dissociates from chromosomes at anaphase onset. Nonacetylated Smc3 is required as a substrate for cohesion establishment in the following cell cycle. Our results complete the description of an Smc3 acetylation cycle and provide unexpected insight into the importance of de novo Smc3 acetylation for cohesion establishment.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylation
  • Acetyltransferases / genetics
  • Acetyltransferases / metabolism
  • Anaphase / physiology
  • Cell Cycle Proteins / genetics
  • Cell Cycle Proteins / metabolism*
  • Chromosomal Proteins, Non-Histone / genetics
  • Chromosomal Proteins, Non-Histone / metabolism*
  • Chromosomes, Fungal / genetics
  • Chromosomes, Fungal / metabolism
  • G1 Phase / physiology
  • Histone Deacetylases / genetics
  • Histone Deacetylases / metabolism*
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism
  • S Phase / physiology
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*


  • Cell Cycle Proteins
  • Chromosomal Proteins, Non-Histone
  • Nuclear Proteins
  • SMC3 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • cohesins
  • Acetyltransferases
  • ECO1 protein, S cerevisiae
  • Histone Deacetylases

Associated data

  • GEO/GSE22257