摘要
目的:评价ITS/ITS2热点条形码序列对新疆4种绢蒿属植物及其近缘种银蒿的鉴别能力,为绢蒿属植物分类鉴定提供分子参考依据。方法:对15份绢蒿属及银蒿植物样本进行DNA提取、PCR扩增、双向测序,采用CodonCode Aligner软件对序列峰图进行校对拼接,MEGA6.0分析序列碱基组成及变异,计算K2P遗传距离并构建聚类邻接树,预测ITS2序列二级结构,评估鉴别能力。结果:西北绢蒿、针裂叶绢蒿种内变异位点及信息位点数均小于银蒿。ITS序列种间、种内遗传变异均大于ITS2序列。ITS/ITS2序列邻接(NJ)树均聚为3支,绢蒿属、银蒿1、银蒿2。绢蒿属ITS2序列二级结构与银蒿有差异。结论:通过ITS/ITS2序列的种间K2P遗传距离、邻接树、ITS2序列二级结构分析,ITS、ITS2序列具很好的属鉴定效果,不同产地的针裂叶绢蒿被区分开。
This study aimed to evaluate DNA barcoding,ITS/ITS2 sequence technique,in identification of four common Seriphidium species and A.austriaca in Xinjiang,which provided molecular basis for the identification of plants in Seriphidium.ITS/ITS2 regions from fifteen Seriphidium species and A.austriaca samples were amplified and sequenced,then assembled by the CodonCode Aligner software.Base composition and variations were analyzed by MEGE 6.0 software.In order to evaluate identification efficiency of ITS/ITS2 barcode,K2P distances of ITS/ITS2 regions were calculated and neighbor-joining（NJ） trees were constructed.ITS2 sequences of the secondary structure were predicted in ITS2 database.It was found that intra-specific variable sites and Parsim-Informative sites of S.nitrosum and S.sublessingianum were less than those of A.austriaca.Interand intra-specific variable sites and Parsim-Informative sites of ITS sequences were more than those of ITS2 sequences.The inter- and intra-specific genetic distances（K2P） of ITS sequences was larger than those of ITS2.All the sequences were clustered into three clades,Seriphidium,A.austriaca 1 and A.austriaca 2,in the NJ trees that constructed with ITS/ITS2 sequences.Secondary structure of ITS2 sequences of four Seriphidium species was different from that of A.austriaca.It was concluded that ITS and ITS2 sequences can identify genus level of 5.sublessingianum from different origin efficiently by K2 P genetic distance,NJ tree and ITS2 secondary structure model.
出处
《世界科学技术-中医药现代化》
2016年第2期221-229,共9页
Modernization of Traditional Chinese Medicine and Materia Medica-World Science and Technology
基金
中科院"西部之光"人才培养计划西部博士资助项目(XBBS201213):新疆蒿属药用植物DNA条形码研究
负责人:刘戈宇
