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Mechanism of chromatin remodeling.

ABSTRACT: Results from biochemical and structural studies of the RSC chromatin-remodeling complex prompt a proposal for the remodeling mechanism: RSC binding to the nucleosome releases the DNA from the histone surface and initiates DNA translocation (through one or a small number of DNA base pairs); ATP binding completes translocation, and ATP hydrolysis resets the system. Binding energy thus plays a central role in the remodeling process. RSC may disrupt histone-DNA contacts by affecting histone octamer conformation and through extensive interaction with the DNA. Bulging of the DNA from the octamer surface is possible, and twisting is unavoidable, but neither is the basis of remodeling.

SUBMITTER: Lorch Y

PROVIDER: S-EPMC2817641 | biostudies-literature | 2010 Feb

REPOSITORIES: biostudies-literature

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Mechanism of chromatin remodeling.

Lorch Yahli Y Maier-Davis Barbara B Kornberg Roger D RD

Proceedings of the National Academy of Sciences of the United States of America 20100208 8

Results from biochemical and structural studies of the RSC chromatin-remodeling complex prompt a proposal for the remodeling mechanism: RSC binding to the nucleosome releases the DNA from the histone surface and initiates DNA translocation (through one or a small number of DNA base pairs); ATP binding completes translocation, and ATP hydrolysis resets the system. Binding energy thus plays a central role in the remodeling process. RSC may disrupt histone-DNA contacts by affecting histone octamer ...[more]

PMID: 20142505

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