基于cytb和rag2基因探讨叶须鱼属分子系统进化关系  

The Molecular Phylogenetic Relationship of the Ptychobarbus Fish Based on cytb and rag2 Genes

作　　者：陈鲆 曾如奎 杨德英[1,2] 哈西 罗文杰 徐丹 刘飞 秦云鑫 熊金鑫 丁文祥 黄俊杰 刘日 唐子婷 何智 严太明[1,2] CHEN Ping;ZENG Rukui;YANG Deying;HA Xi;LUOWenjie;XU Dan;LIU Fei;QIN Yunxin;XIONG Jinxiin;DING Wenxiang;HUANG Junjie;LIU Ri;TANG Ziting;HE Zhi;YAN Taiming(College of Animal Science and Technology,Sichuan Agricultural University,Chengdu 611130,China;Fish Resources and Environment in Upper Reaches of the Yangtze River Observation and Research Station of Sichuan Province,Chengdu 611130,China;Yalong River Hydropower Development Company,Ltd.Chengdu 610051,China)

机构地区：[1]四川农业大学动物科技学院,成都611130 [2]长江上游鱼类资源与环境四川省野外科学观测研究站,成都611130 [3]雅砻江流域水电开发有限公司,成都610051

出　　处：《四川农业大学学报》2024年第1期140-148,共9页Journal of Sichuan Agricultural University

基　　金：雅砻江流域水电开发有限公司资助(YLGZ-LHDA-ZD2022257);国家自然科学基金(31972777)。

摘　　要：【目的】探究叶须鱼属的分子系统进化关系,筛选种间鉴定分子标记。【方法】构建叶须鱼属的cytb(5个种)和rag2(修长叶须鱼和裸腹叶须鱼)基因序列的NJ及贝叶斯系统进化树,并结合核苷酸多态位点、单倍型、核酸多态性、遗传距离、遗传分化系数和基因流等,分析种间进化关系和种内遗传多样性。【结果】叶须鱼属每个种的cytb序列单独聚为一支,表明cytb基因序列能将叶须鱼属5个种区分开;种间高度遗传分化(F_(st)>0.25),物种之间基因流较弱(Nm<1);修长叶须鱼遗传多样性水平最高,锥吻叶须鱼遗传多样性水平最低。基于rag2基因序列的分子系统发育进化树显示,修长叶须鱼和裸腹叶须鱼均单独聚为一支,为独立的种。【结论】cytb和rag2可作为叶须鱼属种间鉴定的分子标记基因,这为叶须鱼属物种的鉴定和系统分类奠定了基础,也为叶须鱼属鱼类保护措施的制定提供了遗传学依据。【Objective】The objective of this study is to explore the molecular phylogenetic relationship of the Ptychobarbus and screen molecular markers for species identification.【Method】NJ and Bayesian evolutionary trees of the cytb(5 species)and rag2(P.kaznakovi and P.leptosomus)gene sequences of Ptychobarbus were constructed.Interspecific evolutionary relationships and intraspecific genetic diversity were analyed based on nucleotide polymorphic sites,haplotypes,nucleic acid polymorphisms,genetic distance,genetic differentiation coefficient,and gene flow.【Result】The cytb sequences of each species were individually clustered into a single branch,indicating that the cytb gene can clearly distinguish the five species of Ptychobarbus.There was a high degree of genetic differentiation(F_(st)>0.25)among 5 species of Ptychobarbus,and the gene flow between species was weak(Nm<1).The genetic diversity level of P.leptosomus was the highest,while the genetic diversity level of P.conirostris was the lowest.The molecular phylogenetic evolution tree of the rag2 gene showed that P.kaznakovi and P.leptosomus were clustered into a single branch.They are independent species.【Conclusion】cytb and rag2 can be used as molecular marker genes for interspecific identification of Ptychobarbus.The above results provide the foundation for the establishment and systematic classification of Ptychobarbus,and the genetic basis for the development of conservation measures for Ptychobarbus.

关 键 词：叶须鱼属 CYTB基因 rag2基因 系统发育关系 遗传多样性 

分 类 号：Q341[生物学—遗传学] S917.4[农业科学—水产科学]