Orientallactaga sibirica isolate:NJNU2020 Genome sequencing. Orientallactaga sibirica isolate:NJNU2020

Jerboas is a lineage of small rodents developing atypical mouse-like morphology with elongated strong hindlimbs and short forelimbs, and well adapted to vast desert-like habitats by obligate bipedal saltation and acute senses. However, knowledge on the evolutionary mechanisms under their limb development, bipedal saltation and environmental adaptation is limited. With a chromosome-scale genome of the Mongolian five-toed jerboa (Orientallactaga sibirica), we explored the mechanisms involved in their unique phenotypes and adaptation through comparative genomics on protein-coding and non-coding regions, and in vitro functional assay. We revealed that to adapt to the growing global cooling and drying from the Eocene-Oligocene transition, jerboas diverged and evolved disproportionate limbs (i.e., long strong hindlimbs and short forelimbs) contributing to bipedal saltation (XYLT1 and CHSY1 in proteoglycan PG biosynthesis), adequate energy and water metabolism (ND5 and ROR2) and acute senses (expanded vomeronasal receptor and FAM136A gene family). The present study provides more resources and new insights for our understanding of the molecular basis underlying phenotypic diversity and environmental adaptation of mammals.