Parental thermal environment controls the offspring phenotype in Brook charr (Salvelinus fontinalis): insights from a transcriptomic study.

Acclimation to high temperatures associated with global climatic change is a vital challenge for cold-adapted fishes such as brook charr (Salvelinus fontinalis). Environmental variation can potentially induce phenotypic changes that are inherited across generations via epigenetic mechanisms that may allow for adaptive rapid responses to changing conditions. Yet, our understanding of epigenetic mechanisms underlying transgenerational plasticity is still limited. In this study, we aimed to determine if epigenetic changes modulating gene expression modifications are associated with transgenerational plasticity. Adults brook charr were exposed to either cold (from 11.5°C in September to 3°C in December) or warm (from 13.5°C in September to 5°C in December) thermal profiles during sexual maturation. Families were produced using a replicated two-by-two breeding design. Eggs from each family were split in two batches, one incubated at 5 °C and the second one at 8°C. The same thermal conditions were maintained from hatching to yolk sac resorption. Using RNA sequencing from brain tissue, we obtained 7881 differentially expressed genes (DGE) between the warm and the cold parental thermal regime. The data uploaded represent the raw data from the RNA sequencing of 67 samples. A total of 6.5 billion reads were sequenced, with an average of 97.4 million reads per sample. Our results reinforce the relevance of epigenetic inheritance in response to climate change. Such inheritance may be an important mechanism associated with buffering the effects of global warming in future generations of brook charr.