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Barrier proteins remodel and modify chromatin to restrict silenced domains.

ABSTRACT: Transcriptionally active and inactive domains are frequently found adjacent to one another in the eukaryotic nucleus. To better understand the underlying mechanisms by which domains maintain opposing transcription patterns, we performed a systematic genomewide screen for proteins that may block the spread of silencing in yeast. This analysis identified numerous proteins with efficient silencing blocking activities, and some of these have previously been shown to be involved in chromatin dynamics. We isolated subunits of Swi/Snf, mediator, and TFIID, as well as subunits of the Sas-I, SAGA, NuA3, NuA4, Spt10p, Rad6p, and Dot1p complexes, as barrier proteins. We demonstrate that histone acetylation and chromatin remodeling occurred at the barrier and correlated with a block to the spread of silencing. Our data suggest that multiple overlapping mechanisms were involved in delimiting silenced and active domains in vivo.

SUBMITTER: Oki M

PROVIDER: S-EPMC350565 | biostudies-literature | 2004 Mar

REPOSITORIES: biostudies-literature

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Barrier proteins remodel and modify chromatin to restrict silenced domains.

Oki Masaya M Valenzuela Lourdes L Chiba Tomoko T Ito Takashi T Kamakaka Rohinton T RT

Molecular and cellular biology 20040301 5

Transcriptionally active and inactive domains are frequently found adjacent to one another in the eukaryotic nucleus. To better understand the underlying mechanisms by which domains maintain opposing transcription patterns, we performed a systematic genomewide screen for proteins that may block the spread of silencing in yeast. This analysis identified numerous proteins with efficient silencing blocking activities, and some of these have previously been shown to be involved in chromatin dynamics ...[more]

PMID: 14966276

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Barrier proteins remodel and modify chromatin to restrict silenced domains.

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Barrier proteins remodel and modify chromatin to restrict silenced domains.

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