基于ITS2序列的茄科酸浆属植物的DNA分子鉴定

DNA Molecular Identification of Physalis Medicinal Plants in Solanaceae by ITS2 Barcode Sequence

目的:利用内转录间隔区2(internal transcribed spacer 2,ITS2)序列对茄科酸浆属植物进行分子鉴定。方法:对酸浆属与散血丹属植物样本的ITS2序列进行逆转录-聚合酶链式反应(RT-PCR)扩增和测序。为扩大研究范围,从Gen Bank中下载了上述2个属植物样本的ITS2序列。所有序列经Codon Code Aligner V3.0.1软件拼接,DNAMAN软件比对分析,采用MEGA 5.10计算相关数据,基于K2P模型构建邻接聚类树。从ITS2数据库中获得所测样本及下载序列的ITS2二级结构信息,分析各样本间ITS2序列二级结构的差异。结果:从邻接聚类树分析可知,所有样本被聚为两大支。酸浆属植物自成1支,散血丹属植物为1支,且除极个别样本外,2个属的各物种种内样本可各为1支,表现出单系性;且每2支之间的Bootstrap支持率均很高。结论:ITS2序列在近缘物种间的系统学研究、品种的鉴定方面具有较大的应用潜力,适用于酸浆属植物的分子鉴定。

Objective： To identify Physalis plants in Solanaceae by internal transcribed spacer 2（ ITS2）sequence. Method： ITS2 sequence of Physalis and Physaliastrum medicinal plant samples was amplified by RTPCR and sequenced. In order to expand scope of research topic, ITS2 sequences of related species were downloaded from Gen Bank. All sequences were spliced by Codon Code Aligner V3. 0. 1, ITS2 sequences were compared and analyzed by DNAMAN software. Related data analysis and processing was performed by MEGA 5. 10 software and neighbor-joining tree was constructed. ITS2 secondary structure information was predicted by ITS2 database and its differences of samples was analyzed. Result： All samples were clustered into two branches,Physaliastrum was clustered into a single branch and the same as Physalis. Except a few samples,all species of both genus were clustered into a branch where all intra-species samples were clustered to one branch respectively and obviously distinguished, which showed monophyletic. Bootstrap support rates between each two were very high. Conclusion： ITS2 sequences have great potential in terms of systematic research and species identification between related species.