Epigenetic mechanisms have the potential to mediate long-term plastic responses to environmental changes. Part of this adaptive plasticity occurs almost immediately after new stress exposure, through coordinated modulation of gene expression associated with the epigenetic machinery. Long-lived sessile organisms, such as trees, are able to accumulate both environmental-induced and spontaneous epimutations. This accumulated memory will likely influence plant ability to respond to novel situations. However, the specific epigenetic mechanisms of phenotypic plasticity are still far from be completely understood. In this study we examined the effects of different stresses (heat, cold, drought, herbivory, rust infection, and salicylic acid signalling) on DNA methylation in a clonal tree by WGBS, using Populus nigra var. italica as model. Variation in CpG/CHG methylation was mainly explained by tree provenance, while CHH methylation showed higher stress responsiveness. A total of 729 differentially methylated regions (DMRs) were identified (659 stress-specific). Drought stress induced a high proportion of DMRs (477), most of them were in CHH context and hypermethylated. This study illustrates the effect of specific stresses on DNA methylation, and also shows how plants can remodel the background landscape of 5-methylcytosine depending on the environment. This remodelling varies between gene regions and between sequence contexts.
|Publication status||Published - 10 May 2020|
|Event||Black Forest Summer School 2020 (online) - Freiburg, Germany|
Duration: 10 May 2020 → 13 May 2020
|Conference||Black Forest Summer School 2020 (online)|
|Period||10/05/20 → 13/05/20|