十种臂尾轮虫12S rDNA基因序列的PCR扩增及分析

PCR Amplication and Sequence Analysis of Partial 12S rDNA Gene From Ten Brachionus Species( Rotifera)

通过对角突臂尾轮虫、尾突臂尾轮虫、裂足臂尾轮虫、剪形臂尾轮虫、方形臂尾轮虫、壶状臂尾轮虫、红臂尾轮虫、镰形臂尾轮虫、萼花臂尾轮虫和十指臂尾轮虫等十种臂尾轮虫和矩形龟甲轮虫的12S rDNA基因进行扩增和序列测序,结合Genbank中两种褶皱臂尾轮虫的125rDNA序列,使用MEGA软件构建这13种轮虫系统发生树(NJ树),探讨了12种臂尾轮虫之间的系统关系.结果表明:本研究所涉及的轮虫12S rDNA序列差异百分比均值为34.41%,可作为分子标记应用于轮虫属内种间系统关系研究;系统树支持将十指臂尾轮虫、裂足臂尾轮虫归属于臂尾轮属;壶状臂尾轮虫和红臂尾轮虫是两个独立的种.

Partial sequences of 12 S rDNA gene from Brachionus angularis,B. caudatus,B. diversicornis,B.forficula,B. quadridentatus,B. urceolaris,B. rubens,B. falcatus,B. calyciflorus,B. patulus and Keratella quadrata were amplified and sequenced. Combined with 12 s rDNA of B. plicatilis and B. koreanus from Genbank,phylogenetic tree were built based on neighbor-joining（ NJ） method with MEGA software,aiming to reveal their phylogenetic relationships and resolve some taxonomic issues. The results showed that the percentage of divergence for 12 S rDNA gene sequences in 13 samples was averaged 34. 41%. Thus,the 12 S rDNA gene was suitable for exploring the phylogeny and evolution in rotifera. The NJ tree supported that B. patulus and B. diversicornis belong to the genus Brachionus,while B. urceolaris and B. rubens are two potential species.