4种河蓝蛤线粒体COI和16S rRNA基因序列的种间遗传分析

Genetic analysis of mitochondrial COI and 16S rRNA gene fragments from four Potamocorbula species

中文关键词: 河蓝蛤  线粒体  16S rRNA  COI  系统进化

英文关键词: Potamocorbula  mtDNA  16S rRNA gene  COI  molecular phylogeny

中文摘要:

      对光滑河蓝蛤Potamocorbula laevis，黑龙江河蓝蛤Potamocorbula amurensis，焦河蓝蛤Potamocorbula ustulata，红肉河蓝蛤Potamocorbularub romuscula 4个野生种共40个个体的线粒体COI 和16S rRNA基因片段进行了扩增和测序，经过筛选和剪切，得到长度为650 bp和450 bp的片段。序列分析显示，序列的碱基组成中G+C含量较低，16S rRNA基因种间和种内的变异较低，COI基因片段种内和种间的变异较高。以沙海螂Mya arenaria为外群，用MEGA4.0软件中的NJ法构建了系统进化树，通过遗传距离和系统进化树可以看出四种河蓝蛤未能达到不同种之间显著的遗传分化。

英文摘要:

      The gene fragments of the mitochondria COI and 16S rRNA in P. laevis, P. amurensis, P. ustulata and P. rubromuscula were amplified and sequenced. Totally, 40 sequences of COI gene and 16S rRNA were obtained,and they were 650 bp and 450 bp in length after trimming，respectively. It showed a low G+C base composition (38.6%). The result of sequence analysis showed that the intraspecific variation and interspecific variation were lower in 16S rRNA than those in COI gene. 10 mutation sites and 7 haplotypes were detected in the gene fragments of 16S rRNA. Taking M. arenaria as the out-group, the phylogenetic trees were constructed using the method of NJ with the software MEGA4.0. Based on the genetic distance and NJ phylogenetic tree，we found that the four speices of Potamocorbula failed to achieve significant genetic differentiation between species.