Speakers

Biography

Le Veve Audrey is a French postdoc of 29 years old. In 2016, after a bachelor’s degree in agronomic sciences, she did a master's degree in genetics at the University of Nice. For two years, she focused on population and evolutionary genetics. In March 2022, she defended her thesis, supervised by V. Castric, on the evolutionary consequences of dominance at the self-incompatibility locus. Since April 2022, she has been working with Clément Lafon-Placette in Prague. 

Abstract

Climate change poses a significant threat to plant species, potentially pushing them beyond their adaptive capacities. Epigenetic modifications, such as DNA methylation, have emerged as a key mechanism enabling plants to quickly adapt to environmental changes by generating locally adapted phenotypes. These phenotypic changes can even be inherited across multiple generations, thus potentially becoming targets of natural selection. However, whether natural selection can act on these epialleles has hardly been tested directly. Addressing this knowledge gap is crucial as population survival may heavily rely on DNA methylation, especially in populations with restricted genetic diversity, such as within clonal plant species.

We compared the genomic and epigenomic diversity from seven natural populations of four individuals of woodland strawberry clonal species (Fragaria vesca). We distinguished the epigenome on the three methylation contexts (CG, CHG, CHH). Specifically, we investigated the effect of the wide altitudinal range on the diversity of these epigenomes and of the genome. Moreover, we studied the heritability of the epigenetic diversity across clonal generations in new environments at low altitudes. 

Our analyses found a wide intra- and interpopulation epigenetic diversity despite a considerably low genetic diversity. We identified heritable epialleles exhibiting signs of positive selection associated with altitude in the CG, CHG, and CHH contexts. Interestingly, some of these epialleles were independent of genetic variation, suggesting they may have arisen stochastically or in response to environmental variation. These findings hint at the role of epigenetic variation in facilitating rapid adaptation to varying environments in the face of reduced genetic diversity, as in clonal species.