基于线粒体16S rDNA和COΙ基因探讨中国近海黄姑鱼类的分子系统进化关系

MOLECULAR PHYLOGENETY OF SPECIES NIBEA IN 16S RDNA AND CYTOCHROME C OXIDASE SUBUNIT Ⅰ MITOCHONDRIAL GENES

为探讨中国近海黄姑鱼类的系统进化关系,通过PCR扩增了黄姑鱼(Nibea albifora)、浅色黄姑鱼(N.coibor)、日本黄姑鱼(N.japonica)和状黄姑鱼(N.miichthioides)等4种黄姑鱼类的16S rDNA和COΙ基因片段并进行了序列测定,计算其种间及种内遗传距离并结合来自GenBank的13种石首鱼科鱼类的相应基因片段序列构建分子系统树。结果表明:(1)利用16S rDNA片段可以对4种黄姑鱼类进行分子鉴定;但是基于COΙ基因片段计算的日本黄姑鱼和状黄姑鱼的种间遗传距离为0.002—0.005,尚未达到种间分化水平,应用该基因片段进行这两种鱼的分子鉴定值得商榷;(2)分子系统树显示日本黄姑鱼和状黄姑鱼与黄姑鱼和浅色黄姑鱼处于不同的系统发育阶元,日本黄姑鱼和状黄姑鱼与白姑鱼属鱼类聚为同一类群,支持形态学上将日本黄姑鱼和状黄姑鱼划归为白姑鱼属的分类学观点。

To understand the evolutionary relationships in four Nibea fish species including Nibea albifora, N. ciobor, N. japonica, and N. miichthioides, partial sequences of 16S rDNA and cytochromec oxidase subunit Ⅰ(COⅠ) mitochondrial genes were PCR-amplified and sequenced. The inter- and intra-specific genetic distance was calculated for species identification and phylogenetic building on available sequences from homologous regions of 13 other Sciaenidae species registered in GenBank. The results show that:(1) molecular identification is practical in the four species in 16S rDNA sequence. However, the inter-specific genetic distance between N. japonica and N. miichthioides was 0.002–0.005 in COⅠ gene and thereby molecular identification for the two fish species using COⅠ gene was questionable;(2) the phylogenetic relationship between N. japonica and N. miichthioides are genetically diverged from N. albifora and N. ciobor but clustered with genus Argyrosomus. Therefore, we suggest that the taxonomy shall be revised on genus Nibea, to which N. japonica and N. miichthioides should be placed in genus Argyrosomus.