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Identification of residues in chromodomain helicase DNA-binding protein 1 (Chd1) required for coupling ATP hydrolysis to nucleosome sliding.

ABSTRACT: Chromatin remodelers are ATP-dependent machines responsible for directionally shifting nucleosomes along DNA. We are interested in defining which elements of the chromodomain helicase DNA-binding protein 1 (Chd1) remodeler are necessary and sufficient for sliding nucleosomes. This work focuses on the polypeptide segment that joins the ATPase motor to the C-terminal DNA-binding domain. We identify amino acid positions outside the ATPase motor that, when altered, dramatically reduce nucleosome sliding ability and yet have only ?3-fold reduction in ATPase stimulation by nucleosomes. These residues therefore appear to play a role in functionally coupling ATP hydrolysis to nucleosome sliding, and suggest that the ATPase motor requires cooperation with external elements to slide DNA past the histone core.

SUBMITTER: Patel A

PROVIDER: S-EPMC3243530 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature

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Identification of residues in chromodomain helicase DNA-binding protein 1 (Chd1) required for coupling ATP hydrolysis to nucleosome sliding.

Patel Ashok A McKnight Jeffrey N JN Genzor Pavol P Bowman Gregory D GD

The Journal of biological chemistry 20111028 51

Chromatin remodelers are ATP-dependent machines responsible for directionally shifting nucleosomes along DNA. We are interested in defining which elements of the chromodomain helicase DNA-binding protein 1 (Chd1) remodeler are necessary and sufficient for sliding nucleosomes. This work focuses on the polypeptide segment that joins the ATPase motor to the C-terminal DNA-binding domain. We identify amino acid positions outside the ATPase motor that, when altered, dramatically reduce nucleosome sli ...[more]

PMID: 22039057

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