ISWI chromatin remodellers sense nucleosome modifications to determine substrate preference.

TitleISWI chromatin remodellers sense nucleosome modifications to determine substrate preference.
Publication TypeJournal Article
Year of Publication2017
AuthorsDann, GP, Liszczak, G, Bagert, JD, Müller, MM, Nguyen, UTT, Wojcik, F, Brown, ZZ, Bos, J, Panchenko, T, Pihl, R, Pollock, SB, Diehl, KL, C Allis, D, Muir, TW
Date Published2017 Aug 02

ATP-dependent chromatin remodelers regulate access to genetic information by controlling nucleosome positions in vivo(1). However, the mechanism by which remodelers discriminate between different nucleosome substrates is poorly understood. Considering that many chromatin remodeling proteins possess conserved protein domains that interact with nucleosomal features(2), we employed a quantitative high-throughput approach, based on the use of a DNA-barcoded mononucleosome library, to profile the biochemical activity of human ISWI remodelers in response to a diverse set of nucleosome modifications. We show that accessory (non-ATPase) subunits of ISWI remodelers can distinguish between differentially modified nucleosomes, directing remodeling activity toward specific nucleosome substrates based on their modification state. Unexpectedly, we discover the nucleosome acidic patch(3) as necessary for maximum activity of all ISWI remodelers evaluated. We find this dependence also extends to CHD and SWI/SNF family remodelers, suggesting the acidic patch may be generally required for chromatin remodeling. Critically, we observe that remodeling activity can be regulated by modifications neighboring the acidic patch, signifying it may act as a tunable interaction hotspot for ATP-dependent chromatin remodelers and, by extension, many other chromatin effectors that engage this region of the nucleosome surface(4-9).

Alternate JournalNature
PubMed ID28767641