粤东海域褐菖鲉种群线粒体DNA控制区序列变异及其在平鲉亚科中的分类地位

Genetic diversity of Sebastiscus marmoratus in eastern Guangdong coastal waters and its taxonomic status in Sebastidae

中文关键词: 褐菖鲉  线粒体DNA  遗传变异  分子系统

英文关键词: Sebastiscus marmoratus  Mitochondrial DNA  Genetic diversity  Phylogeny

中文摘要:

      对捕自粤东海域的47尾野生褐菖鲉Sebastiscus marmoratus线粒体DNA控制区序列进行了扩增和序列变异分析，并结合GenBank中10种其他平鲉亚科的同源序列，分析了平鲉亚科的分子系统。结果表明，所获序列长度在538～544 bp之间，具69个碱基替换位点和36个插入／缺失位点；控制区碱基组成中，A、T、C、G含量分别为34.5 %、29.0 %、15.8 %、20.7 %。共检测到38个单倍型。该种群的单倍型多样度(Hd)和核苷酸多样性(Pi) 分别为0.978和0.019 2。以鲉亚科棘鲉Hoplosebastes armatus作为外群构建的分子系统树显示，褐菖鲉为11种平鲉亚科中较早分化出的种，位于进化树的基部；平鲉亚科为单系群，分为4个分支，分别为平鲉属Sebastes、菖鲉属Sebastiscus、眶棘鲉属Hozukius和无鳔鲉属Helicolenus，与传统的分类地位一致。研究结果表明，控制区序列不仅适合褐菖鲉种群遗传多样性研究，同样也适合分子系统发育研究。

英文摘要:

      The gene fragments of mitochondrial DNA control region of 47 individuals of Sebastiscus marmoratus from eastern Guangdong coastal waters were amplified, sequenced and analyzed.By comparing with 10 corresponding D-loop gene sequences of Sebastidae from GenBank, the taxonomic status of Sebastidae was examined. Fragments (538~544 bp) of control region in mtDNA from 47 individuals of S.marmoratus were determined.A total of 69 variable nucleotide sites and 36 sites with gaps/missing were found and 38 haplotypes were defined. The relative amounts of A, T, C and G bases were 34.5 %，29.0 %，15.8 % and 20.7 %, respectively. The average number of haplotype diversity (Hd) and nucleotide diversity (Pi ) were 0.978 and 0.019 2，respectively. The molecular phylogenetic trees of Sebastidae constructed with H. armatus as outgroup showed that S. marmoratus was basal in the tree and differentiated earlier from their common ancestor. Sebastidae was monophyletic and 11 species were divided into four clades including genus Sebastes, Sebastiscus, Hozukius and Helicolenus, which was consistent with the traditional taxonomic results. In conclusion, mtDNA control region is suitable for the analysis of S.marmoratus not only in population genetic diversity but also in phylogenetic relationship.