Sub-telomeric core X and Y' elements in S. cerevisiae suppress extreme variations in gene silencing

PLoS One. 2011 Mar 17;6(3):e17523. doi: 10.1371/journal.pone.0017523.

Abstract

Telomere Position Effect (TPE) is governed by strong repression signals emitted by telomeres via the Sir2/3/4 Histone Deacetylase complex. These signals are then relayed by weak proto-silencers residing in the subtelomeric core X and Y' elements. Subtelomeres also contain Sub-Telomeric Anti-silencing Regions (STARs). In this study we have prepared telomeres built of different combinations of core X, Y' and STARs and have analyzed them in strains lacking Histone-Acetyltransferase genes as well as in cdc6-1 and Δrif1 strains. We show that core X and Y' dramatically reduce both positive and negative variations in TPE, that are caused by these mutations. We also show that the deletion of Histone-Acetyltransferase genes reduce the silencing activity of an ACS proto-silencer, but also reduce the anti-silencing activity of a STAR. We postulate that core X and Y' act as epigenetic "cushioning" cis-elements.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Chromosomal Position Effects / genetics
  • Gene Deletion
  • Gene Silencing*
  • Genes, Fungal / genetics
  • Histone Acetyltransferases / genetics
  • Saccharomyces cerevisiae / enzymology
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism
  • Telomere / genetics*

Substances

  • Saccharomyces cerevisiae Proteins
  • Histone Acetyltransferases