Identification and characterisation of hypomethylated DNA loci controlling quantitative resistance in Arabidopsis
- University of Sheffield, United Kingdom
- La Trobe University, Australia
- Technical University of Munich, Germany
- Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale), PSL Université Paris, France
Abstract
Variation in DNA methylation enables plants to inherit traits independently of changes to DNA sequence. Here, we have screened an Arabidopsis population of epigenetic recombinant inbred lines (epiRILs) for resistance against Hyaloperonospora arabidopsidis (Hpa). These lines share the same genetic background, but show variation in heritable patterns of DNA methylation. We identified 4 epigenetic quantitative trait loci (epiQTLs) that provide quantitative resistance without reducing plant growth or resistance to other (a)biotic stresses. Phenotypic characterisation and RNA-sequencing analysis revealed that Hpa-resistant epiRILs are primed to activate defence responses at the relatively early stages of infection. Collectively, our results show that hypomethylation at selected pericentromeric regions is sufficient to provide quantitative disease resistance, which is associated with genome-wide priming of defence-related genes. Based on comparisons of global gene expression and DNA methylation between the wild-type and resistant epiRILs, we discuss mechanisms by which the pericentromeric epiQTLs could regulate the defence-related transcriptome.
Data availability
Transcriptome sequencing and bisulfite sequencing reads are available from the European Nucleotide Archive (ENA) under accession code PRJEB26953
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RNA-seq and WBGSEuropean Nucleotide Archive, PRJEB26953.
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Genome-wide Hi-C analyses in wild type and mutants reveal high-resolution chromatin interactions in ArabidopsisNCBI Sequence Read Archive, SRP043612.
Article and author information
Author details
Funding
Leverhulme Trust (RL-2012-042)
- Jurriaan Ton
H2020 European Research Council (RL-2012-042)
- Jurriaan Ton
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Furci 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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Identification and characterisation of hypomethylated DNA loci controlling quantitative resistance in Arabidopsis
eLife 8:e40655.
https://doi.org/10.7554/eLife.40655
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