鲥鱼、太湖新银鱼和大银鱼18S rRNA基因的克隆与序列分析

鲥鱼、太湖新银鱼和大银鱼18S rRNA基因的克隆与序列分析 Cloning and Sequence Analysis of 18S rRNA Gene Fragment of Tenualosa reevesii,Neosalanx taihuensis and Protosalanx hyalocranius 张际峰 ZHANG Jifeng 1 first-author 汪承润 WANG Chengrun 1 王顺昌 WANG Shunchang 1 王春花 WANG Chunhua 1 淮南师范学院生命科学系 淮南师范学院生命科学系 Department of Life Sciences,Huainan Normal University Department of Life Sciences,Huainan Normal University 本文利用多对引物,扩增并测定出鲥鱼、太湖新银鱼和大银鱼18S rRNA基因部分序列,其长度均为1206bp,其中太湖新银鱼与大银鱼基因序列完全相同.将3种经济鱼类与GenBank中10种脊椎动物及头索动物文昌鱼的18S rRNA基因同源序列进行比对分析,计算出序列碱基组成、序列间差异百分比和转换/颠换数值.基于18S rRNA基因序列,利用NJ法、ML法和BI法3种聚类方法,以文昌鱼为外群,构建13种脊椎动物的分子系统树,3种方法获得拓扑学结构一致的系统树.系统树包括3大支,一支为哺乳类、鸟类和爬行类共6个物种,一支为两栖类的2个物种,另一支为5种硬骨鱼类.结果表明:鸟类与哺乳类亲缘关系较近,而胡瓜鱼目与鲑形目亲缘关系近于鲱形目.此外,本文还讨论了脊椎动物18S rRNA基因的序列特征. The partial nucleotide sequences of 18S ribosomal RNA gene were amplified and determined for Tenualosa reevesii,Neosalanx taihuensis,and Protosalanx hyalocranius by PCR with several pairs of specific primers. The nucleotide sequences of 18S rRNA gene of all 3 fishes were 1 206 bp,and the nucleotide sequence of 2 species of salangidae were completely identical. The resulting data were combined with Branchiostoma lanceolatum designed outgroup and additional homologous sequences of 10 species from vertebrates downloaded from GenBank to form the analysis matrix. Nucleotide composition frequencies,the percentage nucleotide sequence divergence,and transition/ transversion ratios were analyzed with the MEGA 3.1 software. Molecular phylogenetic trees constructed by neighbor-joining（NJ）,maximum likelihood （ML）,and Bayesian （BI） methods supported the same topology,in which 13 species of vertebrates could be divided into three major monophyletic groups. The first group contained 6 species of amniotes. The second group comprised 2 species,Bufo guttatus and Hyla sp.,the members of Amphibians （class Amphibia）. The remaining 5 species of fishes belonged to the third group,with a clade comprising Neosalanx taihuensis,Protosalanx hyalocranius,and Salmo salar. The present results indicated that bird was closer to the mammals than to the crocodile,and Osmeriformes was more closely related to Salmoniformes than to Clupeiformes. In addition,several characteristics of 18S rRNA gene sequences were discussed in vertebrates. 鲥鱼 太湖新银鱼 大银鱼 18S rRNA基因 系统分析 Tenualosa reevesii Neosalanx taihuensis Protosalanx hyalocranius 18S rRNA gene phylogenetic analysis 10.14188/j.1671-8836.2010.01.017 S917.4 国家自然科学基金资助项目（20877032）;安徽省教育厅自然科学研究项目（KJ2009B268Z） 2010-01-01 2021-04-01 1 56