基于线粒体COI与16S rRNA基因序列探讨贻贝属的系统发育

比较分析了贻贝属5个种的线粒体DNA COI及16S rRNA基因片段序列,确定了贻贝属的系统进化关系。以翡翠贻贝（Perna viridis）和条纹隔贻贝（Septifer virgatus）为外群,基于距离法（NJ）、最大简约法（MP）、最大似然法（ML）、贝叶斯演绎法（BI）及贝叶斯联合模型分析法构建分子系统树。系统发育分析结果表明,5种贻贝Mytilus edulis,紫贻贝（M.galloprovincialis）,盖勒贻贝（M.trossulus）,厚壳贻贝（M.coruscus）,加州贻贝（M.californianus）]在系统树上聚为2支。加州贻贝最为原始,厚壳贻贝次之。其中,紫贻贝和M.edulis具有很近的亲缘关系,而厚壳贻贝和加州贻贝的亲缘关系近。研究结果为贻贝属物种进化、迁移及其育种研究提供了理论基础。

Molecular phylogenetics of genus Mytilus based on COI and 16S rRNA sequences

In the present study,we compare the partial sequences of mitochondrial COI and 16S rRNA of five genus Mytilus to study their phylogenetic relationship.Taking Perna viridis and Septifer virgatus as outgroups,phylogenetic trees are constructed based on neighbor-joining,maximum parsimony,maximum likelihood,Bayesian inference and combined Bayesian analyses methods.The result demonstrates that Mytilus edulis,M.galloprovincialis,M.trossulus,M.coruscus and M.californianus form into two clades.Among the five species of genus Mytilus,M.californianus is the most primitive,then comes M.coruscus.M.galloprovincialis and M.edulis show very close genetic relationship,and M.coruscus is closer to M.californianus than to M.edulis,M.galloprovincialis and M.trossulus.The molecular phylogeny analysis provides theoretical reference for future comparative study on species evolution,immigration and breeding strategies of Mytilus.