Live-cell single particle imaging reveals the role of RNA polymerase II in histone H2A.Z eviction
- Johns Hopkins University, United States
- National Cancer Institute, United States
- Janelia Research Campus, Howard Hughes Medical Institute, United States
- Stony Brook University, United States
- New York University, United States
Abstract
The H2A.Z histone variant, a genome-wide hallmark of permissive chromatin, is enriched near transcription start sites in all eukaryotes. H2A.Z is deposited by the SWR1 chromatin remodeler and evicted by unclear mechanisms. We tracked H2A.Z in living yeast at single-molecule resolution, and found that H2A.Z eviction is dependent on RNA Polymerase II (Pol II) and the Kin28/Cdk7 kinase, which phosphorylates Serine 5 of heptapeptide repeats on the carboxy-terminal domain of the largest Pol II subunit Rpb1. These findings link H2A.Z eviction to transcription initiation, promoter escape and early elongation activities of Pol II. Because passage of Pol II through +1 nucleosomes genome-wide would obligate H2A.Z turnover, we propose that global transcription at yeast promoters is responsible for eviction of H2A.Z. Such usage of yeast Pol II suggests a general mechanism coupling eukaryotic transcription to erasure of the H2A.Z epigenetic signal.
Data availability
Imaging data have been deposited at Dryad and can be identified by doi:10.5061/dryad.43cp80c
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Live-cell single particle imaging reveals the role of RNA polymerase II in histone H2A.Z evictionDryad Digital Repository, doi:10.5061/dryad.43cp80c.
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Funding
National Institutes of Health (GM125831)
- Carl Wu
National Institutes of Health (GM127538)
- Timothee Lionnet
National Institutes of Health (GM104111)
- Ed Luk
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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Live-cell single particle imaging reveals the role of RNA polymerase II in histone H2A.Z eviction
eLife 9:e55667.
https://doi.org/10.7554/eLife.55667
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