The Chd1 chromatin remodeler shifts hexasomes unidirectionally
Abstract
Despite their canonical two-fold symmetry, nucleosomes in biological contexts are often asymmetric: functionalized with post-translational modifications (PTMs), substituted with histone variants, and even lacking H2A/H2B dimers. Here we show that the Widom 601 nucleosome positioning sequence can produce hexasomes in a specific orientation on DNA, which provide a useful tool for interrogating chromatin enzymes and allow for the generation of precisely defined asymmetry in nucleosomes. Using this methodology, we demonstrate that the Chd1 chromatin remodeler from Saccharomyces cerevisiae requires H2A/H2B on the entry side for sliding, and thus, unlike the back-and-forth sliding observed for nucleosomes, Chd1 shifts hexasomes unidirectionally. Chd1 takes part in chromatin reorganization surrounding transcribing RNA polymerase II (Pol II), and using asymmetric nucleosomes we show that ubiquitin-conjugated H2B on the entry side stimulates nucleosome sliding by Chd1. We speculate that biased nucleosome and hexasome sliding due to asymmetry contributes to the packing of arrays observed in vivo.
Article and author information
Author details
Funding
National Institutes of Health (R01-GM084192)
- Gregory D Bowman
Vetenskapsrådet
- Sebastian Deindl
Knut och Alice Wallenbergs Stiftelse
- Sebastian Deindl
National Institutes of Health (T32-GM007231)
- Robert F Levendosky
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Jerry L Workman, Stowers Institute for Medical Research, United States
Version history
- Received: September 7, 2016
- Accepted: December 28, 2016
- Accepted Manuscript published: December 29, 2016 (version 1)
- Version of Record published: January 11, 2017 (version 2)
Copyright
© 2016, Levendosky et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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