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

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.

SUBMITTER: Zukowski A

PROVIDER: S-EPMC6039258 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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

Zukowski Alexis A Johnson Aaron M AM

Current genetics 20180220 4

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 heterochr ...[more]

PMID: 29464330

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