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Nucleosome sliding by Chd1 does not require rigid coupling between DNA-binding and ATPase domains.

ABSTRACT: Chromatin remodellers are ATP-dependent motor proteins that physically reposition and reorganize nucleosomes. Chd1 and Iswi-type remodellers possess a DNA-binding domain (DBD) needed for efficient nucleosome mobilization; however, it has not been clear how this domain physically contributes to remodelling. Here we show that the Chd1 DBD promotes nucleosome sliding simply by tethering the remodeller to nucleosome substrates. Nucleosome sliding activity was largely resistant to increasing length and flexibility of the linker connecting the DBD and ATPase motor, arguing that the ATPase motor does not shift DNA onto the nucleosome by pulling on the DBD.

SUBMITTER: Nodelman IM

PROVIDER: S-EPMC3981083 | biostudies-other | 2013 Dec

REPOSITORIES: biostudies-other

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Nucleosome sliding by Chd1 does not require rigid coupling between DNA-binding and ATPase domains.

Nodelman Ilana M IM Bowman Gregory D GD

EMBO reports 20131015 12

Chromatin remodellers are ATP-dependent motor proteins that physically reposition and reorganize nucleosomes. Chd1 and Iswi-type remodellers possess a DNA-binding domain (DBD) needed for efficient nucleosome mobilization; however, it has not been clear how this domain physically contributes to remodelling. Here we show that the Chd1 DBD promotes nucleosome sliding simply by tethering the remodeller to nucleosome substrates. Nucleosome sliding activity was largely resistant to increasing length a ...[more]

PMID: 24126763

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