Single-molecule imaging of chromatin remodelers reveals role of ATPase in promoting fast kinetics of target search and dissociation from chromatin
- Johns Hopkins University, United States
- Janelia Research Campus, United States
- Janelia Research Campus, Howard Hughes Medical Institute, United States
- New York University, United States
Abstract
Conserved ATP-dependent chromatin remodelers establish and maintain genome-wide chromatin architectures of regulatory DNA during cellular lifespan, but the temporal interactions between remodelers and chromatin targets have been obscure. We performed live-cell single-molecule tracking for RSC, SWI/SNF, CHD1, ISW1, ISW2, and INO80 remodeling complexes in budding yeast and detected hyperkinetic behaviors for chromatin-bound molecules that frequently transition to the free state for all complexes. Chromatin-bound remodelers display notably higher diffusion than nucleosomal histones, and strikingly fast dissociation kinetics with 4-7 s mean residence times. These enhanced dynamics require ATP binding or hydrolysis by the catalytic ATPase, uncovering an additional function to its established role in nucleosome remodeling. Kinetic simulations show that multiple remodelers can repeatedly occupy the same promoter region on a timescale of minutes, implicating an unending ‘tug-of-war’ that controls a temporally shifting window of accessibility for the transcription initiation machinery.
Data availability
All custom scripts and imaging data files have been deposited in Mendeley Data and are publicly available via: https://data.mendeley.com/datasets/ydwcx9yhpp/2 (DOI: 10.17632/ydwcx9yhpp.2).
Article and author information
Author details
Pat Visanpattanasin
Funding
National Institutes of Health (GM132290)
- Carl Wu
National Institutes of Health (GM127538)
- Timothee Lionnet
Korean Foundation for Advanced Studies Fellowship
- Jee Min Kim
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Kim 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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