Daphnia sinensis genome

The genomic mechanism by which aquatic organisms adapt to high-altitude environments remains unknown. In this study, we provide a high-quality chromosome-level genome assembly (~133 Mb, scaffold N50 11.3 Mb) of a water flea (Daphnia sinensis). This enabled us to discover that there have been chromosomal rearrangements between two subgenera of Daphnia. We further show that the D. sinensis population living on the Tibetan Plateau exhibits several key genomic adaptive features (e.g., enhanced expression of genes associated with DNA repair to cope with harmful UV radiation, response to hypoxia and increased energy metabolism) to cope with the extremely harsh environments at high altitude, when compared with conspecific populations living in low-altitude habitats. These findings provide important insights into the genetic basis of high-altitude adaptation.