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Structure of a RSC-nucleosome complex and insights into chromatin remodeling.

ABSTRACT: ATP-dependent chromatin-remodeling complexes, such as RSC, can reposition, evict or restructure nucleosomes. A structure of a RSC-nucleosome complex with a nucleosome determined by cryo-EM shows the nucleosome bound in a central RSC cavity. Extensive interaction of RSC with histones and DNA seems to destabilize the nucleosome and lead to an overall ATP-independent rearrangement of its structure. Nucleosomal DNA appears disordered and largely free to bulge out into solution as required for remodeling, but the structure of the RSC-nucleosome complex indicates that RSC is unlikely to displace the octamer from the nucleosome to which it is bound. Consideration of the RSC-nucleosome structure and published biochemical information suggests that ATP-dependent DNA translocation by RSC may result in the eviction of histone octamers from adjacent nucleosomes.

SUBMITTER: Chaban Y

PROVIDER: S-EPMC2659406 | biostudies-literature | 2008 Dec

REPOSITORIES: biostudies-literature

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Structure of a RSC-nucleosome complex and insights into chromatin remodeling.

Chaban Yuriy Y Ezeokonkwo Chukwudi C Chung Wen-Hsiang WH Zhang Fan F Kornberg Roger D RD Maier-Davis Barbara B Lorch Yahli Y Asturias Francisco J FJ

Nature structural & molecular biology 20081123 12

ATP-dependent chromatin-remodeling complexes, such as RSC, can reposition, evict or restructure nucleosomes. A structure of a RSC-nucleosome complex with a nucleosome determined by cryo-EM shows the nucleosome bound in a central RSC cavity. Extensive interaction of RSC with histones and DNA seems to destabilize the nucleosome and lead to an overall ATP-independent rearrangement of its structure. Nucleosomal DNA appears disordered and largely free to bulge out into solution as required for remode ...[more]

PMID: 19029894

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