长江上游干流及赤水河蛇遗传多样性与种群历史分析  

Genetic Diversity and Population History of Longnose Gudgeon(Saurogobio dabryi) in the Upper Yangtze River and Chishui River Based on Cytochrome b Gene Sequences

作　　者：李小兵[1,2] 唐琼英[1] 俞丹[1] 刘焕章[1] 

机构地区：[1]中国科学院水生生物研究所,水生生物多样性与保护重点实验室,武汉430072 [2]中国科学院大学,北京100049

出　　处：《动物学杂志》2016年第5期833-843,共11页Chinese Journal of Zoology

基　　金：国家自然科学基金项目(31272306);中国长江三峡集团公司项目(No.0799533);长江上游珍稀特有鱼类及保护区项目(No.0714097)

摘　　要：通过分析76尾来自长江上游干流宜宾（14尾）、合江（30尾）及支流赤水河（32尾）蛇鲍（Saurogobio dabryi）种群的线粒体细胞色素b（cyt b）基因序列，研究蛇鲍3个地理种群的遗传多样性及种群历史。用于分析的Cyt b序列长1097 bp，含变异位点28个，其中简约信息位点18个。76尾个体共检测到26个单倍型，整体呈现较高的单倍型多样性（Hd=0．872）和较低的核苷酸多样性（Pi=0．0040）。三个种群共享较多的单倍型。基于单倍型构建的系统发育树及NETWORK网络关系图显示：所有来自长江上游干流和赤水河的单倍型不能按照地理分布各自聚类，而是相互混杂聚在一起；网络关系图呈星状分布，未检测到原始单倍型和进化中心。此外，基于单倍型频率分析得到的三个种群问的遗传分化指数F ST值较低（分别为-0．0293、0．0280和0．0258）。分子方差分析（AMOVA）显示，整体上长江上游干流及赤水河蛇鲍种群变异主要来源于种群内，种群内的变异占总变异的80．00％，表明长江上游干流及赤水河蛇鲍种群属于同一种群，蛇约各地理种群问基因交流频繁。中性检验、错配分析及BSP（Bayesian skyline plot）分析显示，整体上长江干流及赤水河蛇鲍种群在距今0～0．025Ma（百万年）期间发生过种群扩张现象。The Yangtze River is the longest river in Asia and the third-longest in the world with more than 400 fish species existed. Chishui River is a major tributary of the upper Yangtze River and plays a vital role in the fish resources protection of the Yangtze River. Currently, evolutionary process of Longnose Gudgeon （Saurogobio dabryi）, a fish species widely distributed in Asia, is not known. In this paper, 76 Longnose Gudgeon individuals collected from the upper Yangtze River （marked as Yibin population and Hejiang population respectively） and its tributary Chishui River （marked as Chishui population） were studied by using mitochondrial DNA cytochrome b gene sequences to analyze its genetic diversity and population history. The main results are： 1） The analyzed cytochrome b gene sequences were 1 097 base pairs in length, with 28 variable sites containing 18 parsimony informative sites. Besides, 26 haplotypes were identified from 76 individuals （Table 1）, which showed relatively high haplotype diversity （Hd = 0.872） and low nucleotide diversity （Pi = 0.004 0） respectively （Table 2）; 2） Three populations shared several common haplotypes. Phylogenetic trees based on haplotype dataset by using NJ, ML and BI methods showed that all haplotypes from the upper Yangtze River and Chishui River were not clustered separately according to the geographical distribution. Instead, they mixed with each other （Fig. 2）. Network diagram was also constructed, indicating that all haplotypes had a star-shaped distribution, and original haplotype and evolutionary center could not be detected （Fig. 3）. 3） based on obtained haplotype frequencies, genetic differentiation index （FsT） values among three populations maintained at low levels （ - 0.029 3, 0.028 0 and 0.025 8, respectively） and analysis of molecular variance （AMOVA） showed that overall population divergent variation of Longnose Gudgeon in the upper Yangtze River was mainly from within populations （80.00%） （Table 3）, i

关 键 词：长江上游 赤水河 蛇约 线粒体细胞色素B基因 遗传多样性 

分 类 号：Q958[生物学—动物学]