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The Swi/Snf complex is important for histone eviction during transcriptional activation and RNA polymerase II elongation in vivo.

ABSTRACT: The Swi/Snf nucleosome-remodeling complex is recruited by DNA-binding activator proteins, whereupon it alters chromatin structure to increase preinitiation complex formation and transcription. At the SUC2 promoter, the Swi/Snf complex is required for histone eviction in a manner that is independent of transcriptional activity. Swi/Snf travels through coding regions with elongating RNA polymerase (Pol) II, and swi2 mutants exhibit sensitivity to drugs affecting Pol elongation. In FACT-depleted cells, Swi/Snf is important for internal initiation within coding regions, suggesting that Swi/Snf is important for histone eviction that occurs during Pol II elongation. Taken together, these observations suggest that Swi/Snf is important for histone eviction at enhancers and that it also functions as a Pol II elongation factor.

SUBMITTER: Schwabish MA

PROVIDER: S-EPMC2168902 | biostudies-other | 2007 Oct

REPOSITORIES: biostudies-other

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The Swi/Snf complex is important for histone eviction during transcriptional activation and RNA polymerase II elongation in vivo.

Schwabish Marc A MA Struhl Kevin K

Molecular and cellular biology 20070820 20

The Swi/Snf nucleosome-remodeling complex is recruited by DNA-binding activator proteins, whereupon it alters chromatin structure to increase preinitiation complex formation and transcription. At the SUC2 promoter, the Swi/Snf complex is required for histone eviction in a manner that is independent of transcriptional activity. Swi/Snf travels through coding regions with elongating RNA polymerase (Pol) II, and swi2 mutants exhibit sensitivity to drugs affecting Pol elongation. In FACT-depleted ce ...[more]

PMID: 17709398

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