Evidence of adaptive evolution of alpine pheasants to high-altitude environment from mitogenomic perspective

However, considering the additional vertebrate groups, new perception regarding selection challenged by high-altitude stress on mitochondrial genome can be gained. To test this hypothesis, we compiled and analyzed the mitochondrial genomes of 5 alpine pheasants and 12 low-altitude species in Phasianidae.

The results that evolutionary rates of ATP6 and ND6 showing significant fluctuation among branches when involved with five alpine pheasants revealed both genes might have implications with adapting to highland environment. The radical physico-chemical property changes identified by the modified MM01 model, including composition ( C ) and equilibrium constant (ionization of COOH) ( Pk′ ) in ATP6 and beta-structure tendencies ( P β ), Pk′ , and long-range non-bonded energy ( E l ) in ND6, suggested that minor overall adjustments in size, protein conformation and relative orientation of reaction interfaces have been optimized to provide the ideal environments for electron transfer, proton translocation and generation of adenosine triphosphate (ATP).