Kooke Rik, Johannes Frank, Wardenaar René, Becker Frank, Etcheverry Mathilde, Colot Vincent, Vreugdenhil Dick, Keurentjes Joost J B
Laboratory of Genetics, Wageningen University, 6708 PB Wageningen, The Netherlands Laboratory of Plant Physiology, Wageningen University, 6708 PB Wageningen, The Netherlands Centre for Biosystem Genomics, Wageningen University, 6708 PB Wageningen, The Netherlands.
Groningen Bioinformatics Centre, University of Groningen, 9747 AG Groningen, The Netherlands.
Plant Cell. 2015 Feb;27(2):337-48. doi: 10.1105/tpc.114.133025. Epub 2015 Feb 10.
Epigenetics is receiving growing attention in the plant science community. Epigenetic modifications are thought to play a particularly important role in fluctuating environments. It is hypothesized that epigenetics contributes to plant phenotypic plasticity because epigenetic modifications, in contrast to DNA sequence variation, are more likely to be reversible. The population of decrease in DNA methylation 1-2 (ddm1-2)-derived epigenetic recombinant inbred lines (epiRILs) in Arabidopsis thaliana is well suited for studying this hypothesis, as DNA methylation differences are maximized and DNA sequence variation is minimized. Here, we report on the extensive heritable epigenetic variation in plant growth and morphology in neutral and saline conditions detected among the epiRILs. Plant performance, in terms of branching and leaf area, was both reduced and enhanced by different quantitative trait loci (QTLs) in the ddm1-2 inherited epigenotypes. The variation in plasticity associated significantly with certain genomic regions in which the ddm1-2 inherited epigenotypes caused an increased sensitivity to environmental changes, probably due to impaired genetic regulation in the epiRILs. Many of the QTLs for morphology and plasticity overlapped, suggesting major pleiotropic effects. These findings indicate that epigenetics contributes substantially to variation in plant growth, morphology, and plasticity, especially under stress conditions.
表观遗传学在植物科学界正受到越来越多的关注。表观遗传修饰被认为在波动的环境中起着特别重要的作用。据推测，表观遗传学有助于植物的表型可塑性，因为与DNA序列变异相比，表观遗传修饰更有可能是可逆的。拟南芥中DNA甲基化减少1-2（ddm1-2）衍生的表观遗传重组自交系（epiRILs）群体非常适合研究这一假设，因为DNA甲基化差异最大化而DNA序列变异最小化。在这里，我们报告了在epiRILs中检测到的在中性和盐胁迫条件下植物生长和形态方面广泛的可遗传表观遗传变异。在ddm1-2遗传的表观基因型中，不同的数量性状位点（QTLs）对植物的分枝和叶面积等表现既有降低作用也有增强作用。可塑性的变异与某些基因组区域显著相关，在这些区域中，ddm1-2遗传的表观基因型导致对环境变化的敏感性增加，这可能是由于epiRILs中遗传调控受损所致。许多形态和可塑性的QTLs重叠，表明存在主要的多效性效应。这些发现表明，表观遗传学对植物生长、形态和可塑性的变异有很大贡献，特别是在胁迫条件下。
