Livestock breeds are a reservoir of genetic variation useful for properly responding to agriculture needs during the ongoing climate changes. Evolutionary processes occurring in response to extreme environmental conditions could be better understood using adapted local populations as well. We focused on studying the northernmost cattle from Siberia, the Yakut cattle. We found that Yakut cattle separated from European taurines approximately 5,000-10,000 years ago, escaped major introgression with other Bovinae populations, and contain numerous ancestral and some novel genetic variants allowing their adaptation to harsh conditions of living above the Polar Circle. Our data pointed to a Yakut cattle breed-specific missense mutation in the NRAP gene, involved in heart force transmission. This is a young amino-acid residue convergent change shared with at least 16 species of hibernating/cold-adapted mammals. The follow-up de novo assembly and annotation of the Yakut cattle genome allowed for a systematic search of convergently evolved/selected missense changes in the Yakut cattle proteins and proteins of hibernating, cold-adapted, and deep-diving species. This analysis has confirmed a convergent nature of the NRAP variant and pointed to novel convergently-selected variants in the cattle and hibernating/cold-adapted/deep-diving species’ proteins. Among these were changes in PLA2G4F и PAFAH1B2, previously shown to be under selection in Siberian native human populations, SNX19 involved in regulation of blood pressure and insulin secretion, and POPDC2, controlling the heart rate. Our results suggest multiple acclimation-related convergently evolving events along the mammalian phylogenetic tree and their fast fixation in a single cattle population exposed to a harsh climate.
Dr. Denis Larkin
How Does an Extreme Climate Make Domestic and Wild Animals Evolve Similarly?
Royal Veterinary College, United Kingdom