Concerted regulation of ISWI by an autoinhibitory domain and the H4 N-terminal tail
- Ludwig-Maximilians-Universität München, Germany
- Technische Universität München, Germany
Abstract
ISWI-family nucleosome remodeling enzymes need the histone H4 N-terminal tail to mobilize nucleosomes. Here we mapped the H4-tail binding pocket of ISWI. Surprisingly the binding site was adjacent to but not overlapping with the docking site of an auto-regulatory motif, AutoN, in the N-terminal region (NTR) of ISWI, indicating that AutoN does not act as a simple pseudosubstrate as suggested previously. Rather, AutoN cooperated with a hitherto uncharacterized motif, termed AcidicN, to confer H4-tail sensitivity and discriminate between DNA and nucleosomes. A third motif in the NTR, ppHSA, was functionally required in vivo and provided structural stability by clamping the NTR to Lobe 2 of the ATPase domain. This configuration is reminiscent of Chd1 even though Chd1 contains an unrelated NTR. Our results shed light on the intricate structural and functional regulation of ISWI by the NTR and uncover surprising parallels with Chd1.
Article and author information
Author details
Felix Mueller-Planitz
Funding
Ernst Schering Foundation
- Johanna Ludwigsen
Deutscher Akademischer Austauschdienst
- Ashish K Singh
Deutsche Forschungsgemeinschaft (CIPSM)
- Martin Zacharias
Deutsche Forschungsgemeinschaft (MU 3613/1-1 MU 3613/3-1 SFB 1064/1TP-A07)
- Felix Mueller-Planitz
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2017, Ludwigsen 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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Concerted regulation of ISWI by an autoinhibitory domain and the H4 N-terminal tail
eLife 6:e21477.
https://doi.org/10.7554/eLife.21477
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