The CD59-coding sequences were obtained from 5 mammals by PCR and BLAST, and combined with the available sequences in GenBank, the nucleotide substitution rates of mammalian cd59 were calcu- lated. Results of synonymous and nonsynonymous substitution rates revealed that cd59 experienced negative selection in mammals overall. Four sites experiencing positive selection were found by using "site-specific" model in PAML software. These sites were distributed on the molecular surface, of which 2 sites located in the key functional domain. Furthermore, "branch-site-specific" model detected 1 positive site in cd59a and cd59b lineages which underwent accelerated evolution caused by positive selection after gene duplication in mouse.
GONG YuanYing1,2, PENG MinSheng1,2, ZHOU WeiPing1,3,4 & ZHANG YaPing1,4 1 State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
Chinese snub-nosed monkeys (genus Rhinopithecus, subfamily Colobinae), including R. bieti, R. brelichi and R. roxellana, are well-known as the non-human primates with the highest known altitudinal distribution. They represent an interesting model organism of adaptation to the extreme environmental stresses. However, no study at the molecular level has yet been reported for the high-altitude adaptation in Chinese snub-nosed monkeys. Leptin, as an adipocyte-derived hormone, is believed to play an important role in energy homeostasis in adaptation to high altitude environments. In the present study, we sequenced and compared leptin sequences of the Chinese snub-nosed monkeys (R. bieti and R. roxellana) with their lowland close relative R. avunculus and other Colobines. Unexpectedly, no amino acid changes were observed in the 7 Colobinae species examined, including the 2 Chinese snub-nosed monkeys, indicating no difference in the evolutionary pattern of the Leptin gene between high-altitude monkeys and their lowland counterparts. In contrast to a previous finding of adaptive evolution of Leptin gene in plateau pikas, our study suggests that this gene may not have an important role in high-altitude adaptation of Chinese snub-nosed monkeys. Other nuclear genes associated with energy metabolism, or mitochondrial genes, are most likely to be involved the molecular mechanism underlying adaptation of these monkeys to cold and hypoxia associated with the highland environment.
WANG XiaoPing1,2, JIN Wei1,2, YU Li1,2 & ZHANG YaPing1,2 1 Laboratory for Conservation and Utilization of Bio-resource, Yunnan University, Kunming 650091, China