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Autoinhibitory elements of the Chd1 remodeler block initiation of twist defects by destabilizing the ATPase motor on the nucleosome.

ABSTRACT: Chromatin remodelers are ATP (adenosine triphosphate)-powered motors that reposition nucleosomes throughout eukaryotic chromosomes. Remodelers possess autoinhibitory elements that control the direction of nucleosome sliding, but underlying mechanisms of inhibition have been unclear. Here, we show that autoinhibitory elements of the yeast Chd1 remodeler block nucleosome sliding by preventing initiation of twist defects. We show that two autoinhibitory elements-the chromodomains and bridge-reinforce each other to block sliding when the DNA-binding domain is not bound to entry-side DNA. Our data support a model where the chromodomains and bridge target nucleotide-free and ADP-bound states of the ATPase motor, favoring a partially disengaged state of the ATPase motor on the nucleosome. By bypassing distortions of nucleosomal DNA prior to ATP binding, we propose that autoinhibitory elements uncouple the ATP binding/hydrolysis cycle from DNA translocation around the histone core.

SUBMITTER: Nodelman IM

PROVIDER: S-EPMC7848600 | biostudies-literature |

REPOSITORIES: biostudies-literature

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The chromodomains of the Chd1 chromatin remodeler regulate DNA access to the ATPase motor.

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2.3 A structure of the ATP-dependent chromatin remodeler Chd1 bound to the nucleosome in a nucleotide-free state

Project description: Not available

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

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