摘要
利用线粒体细胞色素c氧化酶Ⅰ亚基(COⅠ)序列研究了南海海区鲻鱼群体的遗传多样性水平和遗传结构。通过PCR扩增与序列测定获得了长度为621bp的基因片段。在35个样品中共发现47处碱基变异,A、T、G、C碱基的平均含量分别为31.6%、24.1%、25.0%和19.2%。35条COⅠ序列共定义了25个单倍型,存在47个多态性位点,产生49个突变。其中,简约信息位点有36个,占总位点数的5.8%,同义替换位点7个,占总变异位点的14.9%,没有发现插入或缺失现象。单倍型多样性(Hd)为0.9563,核苷酸多样性(Pi)为0.02795,平均碱基差异(K)为17.36。Tajima’sD中性检验结果为1.29916,但差异不显著(P>0.10)。采用邻接法(NJ)和非加权配对算术平均法(UPGMA)构建分子系统树,所有的25个单倍型被分成两个分支。结果表明,南海海区鲻鱼种群具有较高的遗传多样性水平。其结果可以为合理开发和利用鲻鱼野生资源,以及建立和保护鲻鱼种质资源提供必要的参考。
Genetic diversity and population structure of Mugil cephalus in the South China Sea were evaluated using a 621-base pair fragment of the mitochondrial cytochrome c oxidase subunit I （CO I ） gene. A total of 47 polymorphic sites defined 25 distinct haplotypes from 35 samples. The average content of A, T, G and C was 31.6%, 24.1%, 25.0%, and 19.2%, respectively. The mean haplotype diversity （Hd）, nucleotide diversity （Pi）, and the average number of uucleotide difference （K） in the Mugil cephalus population were 0.9563, 0.02795, and 17.36, respectively. In all polymorphic sites, 36 parsimony-informative sites （5.8%）, 7 synonymous substitutions （14.9%）, and none of insertions and deletions were found. Result from Tajima＇s D neutrality test for 25 haplotypes was 1.29916 （P〉0.10）. Neighbor-joining （N J） phylogenetic tree and the Unweighted Pair Group Method with Arithmetic （UPGMA） phylogenetic tree divided 25 haplotypes into two clades. The present results revealed that the South China Sea population of Mugil cephalus had a high level of genetic diversity and no range expansion. These results provide basic information for the conservation and sustainable exploitation of this species. Key words Mugil cephalus, Mitochondrial DNA, Cytochrome c oxidase subunit I （CO I ）, Genetic diversity
出处
《海洋与湖沼》
CAS
CSCD
北大核心
2011年第1期131-136,共6页
Oceanologia Et Limnologia Sinica
基金
中央级公益性科研院所基本科研业务费项目,东2009M05号,东2008M14号,东2009M08号
