DNA methylation as a possible mechanism affecting ability of natural populations to adapt to changing climate

Abstract

Environmentally induced epigenetic variation has been recently recognized as a possible mechanism allowing plants to rapidly adapt to novel conditions. Despite increasing evidence on the topic, little is known on how epigenetic variation affects responses of natural populations to changing climate. We studied the effects of experimental demethylation (DNA methylation is an important mediator of heritable control of gene expression) on performance of a clonal grass, Festuca rubra, coming from localities with contrasting temperature and moisture regimes. We compared performance of demethylated and control plants from different populations under two contrasting climatic scenarios and explored whether the response to demethylation depended on genetic relatedness of the plants. Demethylation significantly affected plant performance. Its effects interacted with population of origin and partly with conditions of cultivation. The effects of demethylation also varied between distinct genotypes with more closely related genotypes showing more similar response to demethylation. For belowground biomass, demethylated plants showed signs of adaptation to drought that were not apparent in plants that were naturally methylated. The results suggest that DNA methylation may modify the response of this species to moisture. DNA methylation may thus affect the ability of clonal plants to adapt to novel climatic conditions. Whether this variation in DNA methylation may also occur under natural conditions, however, remains to be explored. Despite the significant interactions between population of origin and demethylation, our data do not provide clear evidence that DNA methylation enabled adaptation to different environments. In fact, we obtained stronger evidence of local adaptation in demethylated than in naturally‐methylated plants. As changes in DNA methylation may be quite dynamic, it is thus possible that epigenetic variation can mask plant adaptations to conditions of their origin due to pre‐cultivation of the plants under standardized conditions. This possibility should be considered in future experiments exploring plant adaptations.

Previous exposure mediates the response of eelgrass to future warming via clonal transgenerational plasticity

“…For example, phenotypic and epigenetic variation is correlated with home‐site environmental variation in clonal poplar cuttings (Vanden Broeck et al 2018) and alligator weed ( A. philoxeroides ; Shi et al 2019). Common stress‐garden experiments applying demethylation treatments demonstrate that demethylation can inhibit clonal TGP, but also alter performance of control plants, making interpretation of these results difficult (Gonzalez et al 2016, Münzbergová et al 2019). Future work on eelgrass epigenetic variation across environmental contexts could greatly enhance our understanding of potential mechanisms driving the clonal TGP described in our results.…”

Manipulation of cytosine methylation does not remove latitudinal clines in two invasive goldenrod species in Central Europe

“…We focused on cytosine methylation, because this is the most thoroughly studied epigenetic mechanism to date, and has been shown to have transgenerational heritability and to play a role in adaptation to environmental stress (Hawes et al., 2018; Herrera & Bazaga, 2010; Herrera et al, 2014). Studies of epigenetic effects in nonmodel organisms have mostly focused on populations in contrasting natural environments (Gao et al., 2010; Herrera & Bazaga, 2016; Lira‐Medeiros et al., 2010), and on apomictic or asexual plant species, such as Taraxacum officinale (Verhoeven & van Gurp, 2012; Wilschut et al., 2016) and Festuca rubra (Münzbergová et al., 2019). There is, to the best of our knowledge, only one other study that has addressed epigenetic latitudinal variation.…”

Centennial clonal stability of asexualDaphniain Greenland lakes despite climate variability

“…There is increasing evidence that epigenetic mechanisms contribute to evolution [63,64] and to adaptive responses related to climate and environmental change [65][66][67]. In the absence of genomic variation, it is becoming increasingly evident that changes in epigenetic profiles could allow for rapid, heritable adaptations to environmental cues that precede the more slowly evolving changes in DNA sequences [68], i.e.…”