都柳江鲇形目两种经济鱼类种群Cyt b基因的遗传多样性分析  

Genetic diversity of Cyt b gene in populations of two commercial siluriformes fishes in Duliujiang River

作　　者：刘伟[1,2] 代应贵[1,2] 袁振兴[1,2] 范家佑[1] 

机构地区：[1]贵州大学动物科学学院,贵阳550025 [2]贵州大学特种水产研究所,贵阳550025

出　　处：《南方农业学报》2016年第10期1766-1771,共6页Journal of Southern Agriculture

基　　金：贵州省留学人员科技活动项目(黔人项目资助合同[2013]10号)

摘　　要：【目的】研究分析贵州都柳江鲇、斑鳢种群细胞色素b基因（Cyt b）的遗传多样性,为都柳江鲇形目经济鱼类资源的保护和开发利用提供参考依据。【方法】以PCR扩增都柳江鲇、斑鳠种群的Cytb基因序列,经双向测序、拼接后采用相关在线软件进行序列变异及遗传多样性分析。【结果】都柳江鲇、斑鳠种群Cyt b基因序列均为1122 bp,分别检测到46和15个变异位点,对应定义为11个单倍型（NHap1-NHap11）和10个单倍型（BHap1-BHap10）。都柳江鲇、斑鳠种群的单倍型多样性指数、核苷酸多样性指数分别为0.646、0.00899和0.610、0.00101。都柳江鲇、斑鳠种群Cytb基因序列均编码374个氨基酸,包含20种氨基酸,以亮氨酸平均含量最高（17.65%和16.58%）、半胱氨酸平均含量最低（0.80%和0.78%）。4种碱基在这两种鱼类Cyt b基因密码子第1位点上出现频率约等,在第2、3位点上的出现频率则存在明显差异。都柳江鲇、斑鳠种群Cyt b基因密码子第3位点上的变异频率显著高于第1和第2位点,但第3位点上的变异多为同义突变。【结论】都柳江鲇种群大小稳定,具有较丰富的遗传多样性;都柳江斑鳠种群遗传多样性较匮乏,可能经历过瓶颈效应和种群扩张事件,急需开展种群保护和恢复工作。【Objective】Genetic diversity of cytochrome b（Cyt b） gene in populations of Silurus asotus and Hemibagrus guttatus in Duliujiang River,Guizhou was studied,in order to supply theoretical basis for resource protection and exploitation of commercial siluriformes fishes in Duliujiang River.【 Method 】 Cyt b genes in populations of S.asotus and H.guttatus in Duliujiang River were amplified using PCR.After bidirectional sequencing and splicing,sequence variation and genetic diversity of Cyt b gene were analyzed using related online softwares.【Result】 Cyt b gene sequences of the two populations comprised of 1122 bp.Forty-six variable sites were detected in S.asotus population while fifteen in H.guttatus population,and they were identified as eleven haplotypes（NHap1-NHap11） and ten haplotypes（BHap1-BHap10） respectively.Haplotype diversity and nucleotide diversity of S.asotus population were 0.646 and 0.00899,whereas those of H.guttatus population were 0.610 and 0.00101.Cyt b gene sequences in the two populations encoded 374 amino acids,including 20 kinds of amino acids.The content of leucine was the highest（17.65%in S.asotus population and 16.58%in H.guttatus population） and that of cysteine the lowest（0.80%in S.asotus population and 0.78%in H.guttatus population）.Occurrence frequencies of four bases at the first site in the two populations were almost the same,but the occurrence frequencies at the second and third sites in the two populations were significantly different.Variation frequencies of Cyt b gene codons at the third site in S.asotus population and H.guttatus population was significantly higher than those at the first and the second sites.But the variation at the third site was synonymous mutation in most cases.【 Conclusion 】S.asotus population is stable in quantity and has high genetic diversity;whereas H.guttatus population has low genetic diversity and probably experienced bottleneck effect and expansion of population.Therefore it is necessary to protect and recover H.guttat

关 键 词：鲇 斑鳠 CYT B基因 遗传多样性 都柳江 

分 类 号：S917[农业科学—水产科学] Q959.4[生物学—动物学]