Mitochondrial genome analysis of Ochotona curzoniae and implication of cytochrome c oxidase in hypoxic adaptation.
Pikas originated in Asia and are small lagomorphs native to cold climates. The plateau pika, Ochotona curzoniae is a keystone species on the Qinghai-Tibet Plateau and an ideal animal model for hypoxic adaptation studies. Altered mitochondrial function, especially cytochrome c oxidase activity, is an important factor in modulation of energy generation and expenditure during cold and hypoxia adaptation. In this study, we determined the complete nucleotide sequence of the O. curzoniae mitochondrial genome. The plateau pika mitochondrial DNA is 17,131bp long and encodes the complete set of 37 proteins typical for vertebrates. Phylogenetic analysis based on concatenated heavy-strand encoded protein-coding genes revealed that pikas are closer to rabbit and hare than to rat. This suggests that rabbit or hare would be a good control animal for pikas in cold and hypoxia adaptation studies. Fifteen novel mitochondrial DNA-encoded amino acid changes were identified in the pikas, including three in the subunits of cytochrome c oxidase. These amino acid substitutions potentially function in modulation of mitochondrial complexes and electron transport efficiency during cold and hypoxia adaptation.
Luo
Yongjun
Y
Department of Pathophysiology and High Altitude Physiology, College of High Altitude Medicine, Third Military Medical University, Chongqing 400038, China.
Gao
Wenxiang
W
Gao
Yuqi
Y
Tang
Sha
S
Huang
Qingyuan
Q
Tan
Xiaoling
X
Chen
Jian
J
Huang
Taosheng
T
D000222:Adaptation, Physiological; D019943:Amino Acid Substitution; D000818:Animals; D004272:DNA, Mitochondrial / Q000235:genetics; D003576:Electron Transport Complex IV / Q000737:chemistry / Q000235:genetics*; D016678:Genome; D000860:Hypoxia / Q000378:metabolism*; D007793:Lagomorpha / Q000235:genetics*; D008297:Male; D008928:Mitochondria / Q000235:genetics*; D010802:Phylogeny
D004272:DNA, Mitochondrial; D003576:Electron Transport Complex IV