Epigenetic silencing of a multifunctional plant stress regulator
- Salk Institute for Biological Studies, United States
- Howard Hughes Medical Institute, Salk Institute for Biological Studies, United States
Abstract
The central regulator of the ethylene (ET) signaling pathway, which controls a plethora of developmental programs and responses to environmental cues in plants, is ETHYLENE-INSENSITIVE2 (EIN2). Here we identify a chromatin-dependent regulatory mechanism at EIN2 requiring two genes: ETHYLENE-INSENSITIVE6 (EIN6), which is a H3K27me3 demethylase also known as RELATIVE OF EARLY FLOWERING6 (REF6), and EIN6 ENHANCER (EEN), the Arabidopsis homolog of the yeast INO80 chromatin remodeling complex subunit IES6 (INO EIGHTY SUBUNIT). Strikingly, EIN6 (REF6) and the INO80 complex redundantly control the level and the localization of the repressive histone modification H3K27me3 and the histone variant H2A.Z at the 5' untranslated region (5'UTR) intron of EIN2. Concomitant loss of EIN6 (REF6) and the INO80 complex shifts the chromatin landscape at EIN2 to a repressive state causing a dramatic reduction of EIN2 expression. These results uncover a unique type of chromatin regulation which safeguards the expression of an essential multifunctional plant stress regulator.
Data availability
Sequence data have been deposited in GEO under accession GSE122314.An overview of all sequenced data is given in Supplementary File 2.Visualized sequencing data can be found under http://neomorph.salk.edu/ein6een.php
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Epigenetic Control of a Multifunctional Stress RegulatorNCBI Gene Expression Omnibus, GSE122314.
Article and author information
Author details
Funding
National Science Foundation (MCB-1024999)
- Joseph R Ecker
National Institutes of Health (5R35 GM122604)
- Joanne Chory
Department of Energy, Office of Basic Energy Sciences (DE-FG02-04ER15517)
- Joseph R Ecker
Gordon and Betty Moore Foundation (GBMF3034)
- Joseph R Ecker
Howard Hughes Medical Institute
- Joseph R Ecker
Deutsche Forschungsgemeinschaft (Za-730/1-1)
- Mark Zander
Salk Pioneer Postdoctoral Endowment Fund
- Mark Zander
Human Frontier Science Program (LT000222/2013-L)
- Björn C Willige
EU Marie Curie FP7 International Outgoing Fellowship (252475)
- Mathew Lewsey
Howard Hughes Medical Institute
- Joanne Chory
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Daniel Zilberman, John Innes Centre, United Kingdom
Version history
- Received: April 20, 2019
- Accepted: August 15, 2019
- Accepted Manuscript published: August 16, 2019 (version 1)
- Version of Record published: September 10, 2019 (version 2)
Copyright
© 2019, Zander 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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Epigenetic silencing of a multifunctional plant stress regulator
eLife 8:e47835.
https://doi.org/10.7554/eLife.47835
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