DNA methylation shows footprints of altitude selection in the clonal plant species Fragaria vesca

Abstract

O_LIClimate change threatens plant species, potentially pushing them beyond their adaptive capacities. DNA methylation and other epigenetic modifications may enable rapid adaptation to environmental changes by generating locally adapted phenotypes. These phenotypic changes can be inherited across generations and may become targets of natural selection. However, direct evidence for selection on epialleles remains scarce. Addressing this gap is crucial, as population survival may heavily rely on DNA methylation, especially in clonal plants with limited genetic diversity. C_LIO_LIWe employed population genomics approaches to investigate altitude-driven selection on epigenetic sites in clonal offspring of natural woodland strawberry (Fragaria vesca) populations. These offspring were grown in a common garden and derived from seven populations spanning an altitudinal range. C_LIO_LIOur genomic, epigenomic, and transcriptomic analyses identified epialleles in clones exhibiting signs of selection related to altitude. These loci overlapped with genes involved in the O-methyltransferase activity, potentially aiding altitude adaptation through enhanced secondary metabolite production. Interestingly, these epialleles were mostly independent of genetic variation, suggesting they may have arisen stochastically or in response to environmental variation. C_LIO_LIThese findings suggest that heritable epigenetic variation could help clonal species quickly adapt to environmental challenges as those related to varying altitudes and/or temperatures. C_LI