Skip to main content
eScholarship
Open Access Publications from the University of California

Telomeric heterochromatin boundaries require NuA4-dependent acetylation of histone variant H2A.Z in Saccharomyces cerevisiae.

  • Author(s): Babiarz, Joshua E
  • Halley, Jeffrey E
  • Rine, Jasper
  • et al.
Abstract

SWR1-Com, which is responsible for depositing H2A.Z into chromatin, shares four subunits with the NuA4 histone acetyltransferase complex. This overlap in composition led us to test whether H2A.Z was a substrate of NuA4 in vitro and in vivo. The N-terminal tail of H2A.Z was acetylated in vivo at multiple sites by a combination of NuA4 and SAGA. H2A.Z acetylation was also dependent on SWR1-Com, causing H2A.Z to be efficiently acetylated only when incorporated in chromatin. Unacetylatable H2A.Z mutants were, like wild-type H2A.Z, enriched at heterochromatin boundaries, but were unable to block spreading of heterochromatin. A mutant version of H2A.Z that could not be acetylated, in combination with a mutation in a nonessential gene in the NuA4 complex, caused a pronounced decrease in growth rate. This H2A.Z mutation was lethal in combination with a mutant version of histone H4 that could not be acetylated by NuA4. Taken together, these results show a role for H2A.Z acetylation in restricting silent chromatin, and reveal that acetylation of H2A.Z and H4 can contribute to a common function essential to life.

Many UC-authored scholarly publications are freely available on this site because of the UC Academic Senate's Open Access Policy. Let us know how this access is important for you.

Main Content
Current View