等边浅蛤(Gomphina aequilatera)核糖体DNA第一内转录间隔区序列的特征分析  

CHARACTERIZATION OF INTERNAL TRANSCRIBED SPACER ONE IN GOMPHINA AEQUILATERA RIBOSOMAL DNA

作　　者：吕锋骅[1] 韩洁[1] 林岿璇[1] 陈万东 

机构地区：[1]生物多样性与生态工程教育部重点实验室,北京师范大学生命科学学院,北京100875 [2]南麂列岛国家级海洋自然保护区,浙江温州325014

出　　处：《北京师范大学学报（自然科学版）》2011年第4期398-404,共7页Journal of Beijing Normal University(Natural Science)

基　　金：北京师范大学优秀博士学位论文培育基金资助项目(10420801);浙江省温州市科技局研究资助项目(S2005A004)

摘　　要：从浙江和福建沿海潮间带的6个采样点各随机选取2个等边浅蛤（Gomphina aequilatera）样品，以聚合酶链式反应、分子克隆和序列测定等分子生物学实验技术获得了ITS-1序列．通过比对发现，该序列内存在一个长度为17bp的插入／缺失片段和一个结构为（GA）3（GGGA）2（GA）4-6。的微卫星DNA，这2个结构是造成等边浅蛤ITS-1序列在个体基因组内及个体之间长度变化的主要原因．统计分析结果显示，该序列在个体基因组内的变异与相同采样点个体之间的变异无显著差异（P〉0．05），而与不同采样点个体之间的变异差异显著（P〈0．05），因此在种群水平的研究中是有效的分子标记．系统发生关系重建的结果和单倍型网络结构图均显示等边浅蛤的ITS-1序列各单倍型间的亲缘关系较近．Internal transcribed spacer one （ITS-1） in ribosomal DNA is a of the molecular marker frequently used in phylogeny, population genetics and species taxonomy studies. However, the presence of variations among multiple copies within individual genome is often neglected. In this study, Gomphina aequilatera ITS-1 sequences of two individual subjects from six sampling sites each at intertidal zone along Zhejiang and Fujian provinces were obtained by polymerase chain reaction, molecular cloning and sequencing. Both an 17 bp segment of insertion/deletion and an imperfect microsatellite DNA with structure of （GA）3 （GGGA）2 （GA）4-6 were detected by sequence alignment G. aequilatera ITS-1 sequence length variations intragenome or among different individuals were caused mainly by those two structures. Statistical analysis revealed that G. aequilatera ITS-1 sequence variation intra-genome was not significantly different from sequence variation between individuals in the same sampling site （P 〉 0.05 ）, but was significantly different from sequence variation among individuals at different sampling sites （P 〈0.05）. Such sequence variation is therefore an effective marker at population level. Phylogeny reconstruction and network analysis indicated that G. aequilatera ITS-1 haplotypes were closely related..

关 键 词：ITS-1 分子标记 序列变异 等边浅蛤 

分 类 号：Q789[生物学—分子生物学]