Natural variation in autumn expression is the major adaptive determinant distinguishing Arabidopsis FLC haplotypes
Abstract
In Arabidopsis thaliana, winter is registered during vernalization through the temperature-dependent repression and epigenetic silencing of floral repressor FLOWERING LOCUS C (FLC). Natural Arabidopsis accessions show considerable variation in vernalization. However, which aspect of the FLC repression mechanism is most important for adaptation to different environments is unclear. By analyzing FLC dynamics in natural variants and mutants throughout winter in three field sites, we find that autumnal FLC expression, rather than epigenetic silencing, is the major variable conferred by the distinct Arabidopsis FLC haplotypes. This variation influences flowering responses of Arabidopsis accessions resulting in an interplay between promotion and delay of flowering in different climates to balance survival and, through a post-vernalization effect, reproductive output. These data reveal how expression variation through non-coding cis variation at FLC has enabled Arabidopsis accessions to adapt to different climatic conditions and year-on-year fluctuations.
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All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for all figures.
Article and author information
Author details
Funding
Horizon 2020 Framework Programme (MEXTIM)
- Jo Hepworth
- Rea L Antoniou-Kourounioti
- Kristina Berggren
- Catja Selga
- Eleri H Tudor
- Deborah Cox
- Barley Rose Collier Harris
- Judith A Irwin
- Martin Howard
- Torbjörn Säll
- Svante Holm
- Caroline Dean
Biotechnology and Biological Sciences Research Council (BB/J004588/1)
- Jo Hepworth
- Rea L Antoniou-Kourounioti
- Eleri H Tudor
- Deborah Cox
- Barley Rose Collier Harris
- Judith A Irwin
- Martin Howard
- Caroline Dean
Biotechnology and Biological Sciences Research Council (BB/P013511/1)
- Jo Hepworth
- Rea L Antoniou-Kourounioti
- Eleri H Tudor
- Bryony Yates
- Deborah Cox
- Barley Rose Collier Harris
- Judith A Irwin
- Martin Howard
- Caroline Dean
Biotechnology and Biological Sciences Research Council (BB/P003095/1)
- Jo Hepworth
- Eleri H Tudor
- Judith A Irwin
Biotechnology and Biological Sciences Research Council (BB/L016079/1)
- Eleri H Tudor
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Hao Yu, National University of Singapore & Temasek Life Sciences Laboratory, Singapore
Version history
- Received: April 8, 2020
- Accepted: September 8, 2020
- Accepted Manuscript published: September 9, 2020 (version 1)
- Version of Record published: September 25, 2020 (version 2)
Copyright
© 2020, Hepworth 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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