Project description:Three-spined stickleback (Gasterosteus aculeatus) represents a convenient model to study microevolution - adaptation to freshwater environment. While genetic adaptations to freshwater are well-studied, epigenetic adaptations attracted little attention. In this work, we investigated the role of DNA methylation in the adaptation of marine stickleback population to freshwater conditions. DNA methylation profiling was performed in marine and freshwater populations of sticklebacks, as well as in marine sticklebacks placed into freshwater environment and freshwater sticklebacks placed into seawater. For the first time, we demonstrated that genes encoding ion channels kcnd3, cacna1fb, gja3 are differentially methylated between marine and freshwater populations. We also showed that after placing marine stickleback into fresh water, its DNA methylation profile partially converges to the one of a freshwater stickleback. This suggests that immediate epigenetic response to freshwater conditions can be maintained in freshwater population. Interestingly, we observed enhanced epigenetic plasticity in freshwater sticklebacks that may serve as a compensatory regulatory mechanism for the lack of genetic variation in the freshwater population. Some of the regions that were reported previously to be under selection in freshwater populations also show differential methylation. Thus, epigenetic changes might represent a parallel mechanism of adaptation along with genetic selection in freshwater environment. This is the RNA-seq experiment, DNA methylation data (bisulfite-seq) is provided under accession number GSE82310.
Project description:Three-spined stickleback (Gasterosteus aculeatus) represents a convenient model to study microevolution - adaptation to freshwater environment. While genetic adaptations to freshwater are well-studied, epigenetic adaptations attracted little attention. In this work, we investigated the role of DNA methylation in the adaptation of marine stickleback population to freshwater conditions. DNA methylation profiling was performed in marine and freshwater populations of sticklebacks, as well as in marine sticklebacks placed into freshwater environment and freshwater sticklebacks placed into seawater. For the first time, we demonstrated that genes encoding ion channels kcnd3, cacna1fb, gja3 are differentially methylated between marine and freshwater populations. We also showed that after placing marine stickleback into fresh water, its DNA methylation profile partially converges to the one of a freshwater stickleback. This suggests that immediate epigenetic response to freshwater conditions can be maintained in freshwater population. Interestingly, we observed enhanced epigenetic plasticity in freshwater sticklebacks that may serve as a compensatory regulatory mechanism for the lack of genetic variation in the freshwater population. Some of the regions that were reported previously to be under selection in freshwater populations also show differential methylation. Thus, epigenetic changes might represent a parallel mechanism of adaptation along with genetic selection in freshwater environment.
Project description:AIM: By adopting comparative transcriptomic approach, we investigated the gene expression of wood decomposing Basidiomycota fungus Phlebia radiata. Our aim was to reveal how hypoxia and lignocellulose structure affect primary metabolism and the expression of wood decomposition related genes. RESULTS: Hypoxia was a major regulator for intracellular metabolism and extracellular enzymatic degradation of wood polysaccharides by the fungus. Our results manifest how oxygen depletion affects not only over 200 genes of fungal primary metabolism but also plays central role in regulation of secreted CAZyme (carbohydrate-active enzyme) encoding genes. Based on these findings, we present a hypoxia-response mechanism in wood-decaying fungi divergent from the regulation described for Ascomycota fermenting yeasts and animal-pathogenic species of Basidiomycota.