基于COI部分序列探讨南海鲳属鱼类系统进化与种群遗传结构

Phylogenetic relationships and population structure of Pampus in the South China Sea inferred from COI gene segments

利用线粒体细胞色素c氧化酶Ⅰ亚基(COI)部分序列研究了南海区鲳属鱼类(Pampus)银鲳(P.ar-genteus)、珍鲳(P.minor)和中国鲳(P.chinensis)的系统进化与种群遗传结构。通过PCR扩增与序列测定获得了长度为643 bp的COI基因片段,其A、T、G、C碱基的平均含量分别为25.4%、33.6%、18.9%和22.1%,A+T含量高于G+C含量。64条序列共定义了20种单倍型,包含152个变异位点,简约信息位点148个,单变异位点4个,产生169个点突变。结果表明,银鲳与中国鲳的遗传差异最小,银鲳与珍鲳的其次,而珍鲳与中国鲳的遗传差异最大,3种鲳属鱼类的遗传多样性均呈现较低的水平,应采取有效的保护措施,以避免其遗传多样性水平的进一步丧失。本研究结果为鲳属鱼类资源保护和合理开发利用提供必要的参考。

Sequence variation and population genetic structure of Pampus argenteus, P. minor and P. chinensis in the South China Sea were evaluated using a 643 base pair fragment of mitochondrial cytochrome c oxidase subunit I （C01） gene. The average contents of A, T, G and C were 25.4%, 33.6%, 18.9%, and 22.1%, respectively. The content of A＋T was much higher. In 64 CO1 sequences, a total of 152 polymorphic sites （including 148 parsimony informative sites and 4 singleton variable sites） formed 169 mutations, and defined 20 distinct haplotypes. P. minor and P. chinensis had the largest genetic divergence, whereas P. argenteus and P. chinensis had the least genetic di- vergence. All three pampus populations presented low level of genetic diversity. Therefore, certain efficient meas- ures should be made to avoid further decline of genetic diversity in those species. The present results provide basic information for the conservation and sustainable exploitation of Pampus species.