Format: ORAL

Conchita Alonso1, Mnica Medrano1, Carlos M. Herrera1

1 Estación Biológica de Doñana, EBD-CSIC, Sevilla, Spain

Epigenetics investigates phenotypic variation that is not accompanied by changes in DNA sequence, but instead involves the set of chromatin modifications that regulate the ability of a certain genome to produce diverse phenotypes. In plants, DNA cytosine methylation is a key epigenetic mechanism involved in genome stability and developmental change. In the last few decades we have learned that Angiosperms have evolved specific DNA methylation enzymes and pathways (e.g., chromomethylases, RNA-directed methylation) which target cytosines in any sequence context and genomic location, and that genome-wide cytosine methylation level is largely variable across species and has a strong phylogenetic signal and phenotypic correlates within and across plant individuals. Furthermore, changes in DNA methylation induced by environmental stress and transgenerational transmission of some methylation marks have been documented for many plant species. It remains unclear, however, the extent to which inter- and intra-specific variation in the ability of a given genotype to produce phenotypic variants depends on intrinsic genomic features and/or the ecological characteristics of their environments. In our group we have assessed epigenetic variation in wild plant populations at different spatial scales and adopted experimental approaches which combined a controlled alteration of epigenetic features (e.g., by applying demethylating agents) with exposure to selected biotic and abiotic stress factors. I will summarize what we have learned from applying these two approaches to a set of non-model plant species. Understanding the relationships between phenotypic traits and changes in DNA methylation in contrasting environments is crucial to uncover the potential impact of epigenetics on fast plant adaptation to changing environments under current scenarios of climate change. Integration of molecular understanding gained from model species and ecological significance assessed in non-model plant species should contribute to better value the contribution of epigenetics in plant adaptation and evolution.