Genomic Nucleosome Organization Reconstituted with Pure Proteins.

Nils Krietenstein, Megha Wal, Shinya Watanabe, Bongsoo Park, Craig L Peterson, B Franklin Pugh, Philipp Korber

Cell 2016 Oct 20

filter terms:

Chromatin remodelers regulate genes by organizing nucleosomes around promoters, but their individual contributions are obfuscated by the complex in vivo milieu of factor redundancy and indirect effects. Genome-wide reconstitution of promoter nucleosome organization with purified proteins resolves this problem and is therefore a critical goal. Here, we reconstitute four stages of nucleosome architecture using purified components: yeast genomic DNA, histones, sequence-specific Abf1/Reb1, and remodelers RSC, ISW2, INO80, and ISW1a. We identify direct, specific, and sufficient contributions that in vivo observations validate. First, RSC clears promoters by translating poly(dA:dT) into directional nucleosome removal. Second, partial redundancy is recapitulated where INO80 alone, or ISW2 at Abf1/Reb1sites, positions +1 nucleosomes. Third, INO80 and ISW2 each align downstream nucleosomal arrays. Fourth, ISW1a tightens the spacing to canonical repeat lengths. Such a minimal set of rules and proteins establishes core mechanisms by which promoter chromatin architecture arises through a blend of redundancy and specialization. Copyright © 2016 Elsevier Inc. All rights reserved.

Citation

Nils Krietenstein, Megha Wal, Shinya Watanabe, Bongsoo Park, Craig L Peterson, B Franklin Pugh, Philipp Korber. Genomic Nucleosome Organization Reconstituted with Pure Proteins. Cell. 2016 Oct 20;167(3):709-721.e12