The interplay of histone H2B ubiquitination with budding and fission yeast heterochromatin

Curr Genet. 2018 Aug;64(4):799-806. doi: 10.1007/s00294-018-0812-1. Epub 2018 Feb 20.

Abstract

Mono-ubiquitinated histone H2B (H2B-Ub) is important for chromatin regulation of transcription, chromatin assembly, and also influences heterochromatin. In this review, we discuss the effects of H2B-Ub from nucleosome to higher-order chromatin structure. We then assess what is currently known of the role of H2B-Ub in heterochromatic silencing in budding and fission yeasts (S. cerevisiae and S. pombe), which have distinct silencing mechanisms. In budding yeast, the SIR complex initiates heterochromatin assembly with the aid of a H2B-Ub deubiquitinase, Ubp10. In fission yeast, the RNAi-dependent pathway initiates heterochromatin in the context of low H2B-Ub. We examine how the different silencing machineries overcome the challenge of H2B-Ub chromatin and highlight the importance of using these microorganisms to further our understanding of H2B-Ub in heterochromatic silencing pathways.

Keywords: Epigenetics; Heterochromatin; SIR complex; Silencing; Ubiquitination; Ubp10.

Publication types

  • Review

MeSH terms

  • Gene Expression Regulation, Fungal
  • Gene Silencing
  • Heterochromatin / genetics*
  • Histones / genetics*
  • Nuclear Proteins / genetics*
  • Saccharomyces cerevisiae Proteins / genetics*
  • Saccharomycetales / genetics
  • Schizosaccharomyces / genetics
  • Silent Information Regulator Proteins, Saccharomyces cerevisiae / genetics*
  • Telomere / genetics
  • Ubiquitin / genetics
  • Ubiquitin Thiolesterase / genetics*

Substances

  • Heterochromatin
  • Histones
  • Nuclear Proteins
  • Saccharomyces cerevisiae Proteins
  • Silent Information Regulator Proteins, Saccharomyces cerevisiae
  • Ubiquitin
  • UBP10 protein, S cerevisiae
  • Ubiquitin Thiolesterase