Taxonomy and Phylogenesis of Chinese Yak Based on the Complete Sequence of Cytochrome c Oxidase Genes in Tianzhu White Yak
It is well known that yak is originated from China, but the fact regarding its taxonomy with other Bovini species, is largely disputed.We cloned 1 545 bp of complete mitochondrial cytochrome c oxidase subunit Ⅰ (coxl, JF946751), 684 bp of cytochrome c oxidase subunit Ⅱ (cox2,JN008944) and 781 bp of cytochrome c oxidase subunit Ⅲ (cox3, JF946752) in Tianzhu with yak.The taxonomy of the Chinese yak and its phylogenetic relationship with other 7 Bovini species were discussed.Results showed that among different Bovini species the nucleotide transition/transversion (Ts/Tv) of cox1, cox2 and cox3 was 9.042, 7.646 and 6.052, respectively, suggesting the mutation was not saturation.The nucleotide divergence percentage between yak and cattle/zebu (5.7% in cox1, 7.7% in cox2 and 6.45% in cox3)was higher than that between yak and American bison (2.4% in cox1, 3.0% in cox2 and 2.1% in cox3).Phylogeny analysis with these three genes also found that yak and American bison firstly clustered in one clade, indicating there was higher genetic comparability than that of cattle/zebu.The findings sustained the idea that in the choice of nomenclature yak belongs to the subgenus of Poephagus.According to the nucleotide substitution rate of cytochrome c oxidase genes among Bovini species, the speculated divergence time of yak from cattle/zebu, American bison, European bison, Asian buffalo/African buffalo was 1.05 ~ 1.50 million years ago (MYA), 2.85 ~ 3.89 MYA, 2.90 ~ 3.70 MYA, 6.85 ~ 7.50 MYA, respectively.The sequential evolution of Bovini members could be predicted that buffalo was first divided into Asian buffalo and African buffalo during the end of Miocene and the early of Pliocene.In the end of Pliocene, Bovini genera were evolved to Bos, Bison and Poephagus.Poephagus, which branched off from the middle of Pleiocene, was the latest evolved genera among the Bovini species.
Yak bovini species cytochrome c oxidase genes taxonomy phylogenetic relationship divergence time
Bai Jialin Jiang Jiayi Yang Jie
Gansu Engineering Research Center for Animal Cell, No.1, New Village of Northwest, Lanzhou, 730030, College of Life Science and Engineering, Northwest University for Nationalities, No.1, New Village o
国际会议
The 5th International Conference on Yak(第五届国际耗牛大会)
兰州
英文
174-183
2014-08-27（万方平台首次上网日期，不代表论文的发表时间）