Asymmetry between the two acidic patches dictates the direction of nucleosome sliding by the ISWI chromatin remodeler
Abstract
The acidic patch is a functionally important epitope on each face of the nucleosome that affects chromatin remodeling. Although related by 2-fold symmetry of the nucleosome, each acidic patch is uniquely positioned relative to a bound remodeler. An open question is whether remodelers are distinctly responsive to each acidic patch. Previously we reported a method for homogeneously producing asymmetric nucleosomes with distinct H2A/H2B dimers (Levendosky et al., 2016). Here, we use this methodology to show that the Chd1 remodeler from Saccharomyces cerevisiae and ISWI remodelers from human and Drosophila have distinct spatial requirements for the acidic patch. Unlike Chd1, which is equally affected by entry- and exit-side mutations, ISWI remodelers strongly depend on the entry-side acidic patch. Remarkably, asymmetry in the two acidic patches stimulates ISWI to slide mononucleosomes off DNA ends, overriding the remodeler's preference to shift the histone core toward longer flanking DNA.
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All data generated in this study are included in the manuscript.
Article and author information
Author details
Funding
National Institute of General Medical Sciences (R01-GM084192)
- Robert F Levendosky
- Gregory D Bowman
National Institutes of Health (R01-GM113240)
- Robert F Levendosky
- Gregory D Bowman
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: January 24, 2019
- Accepted: May 16, 2019
- Accepted Manuscript published: May 16, 2019 (version 1)
- Version of Record published: June 3, 2019 (version 2)
Copyright
© 2019, Levendosky & Bowman
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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