斑叶兰属7种药用植物rDNA ITS序列的克隆与分析

目的克隆和分析7种斑叶兰属药用植物的ITS序列,为该属植物的分子鉴定提供依据。方法利用PCR法克隆ITS序列,在测序的基础上,借助生物信息学软件进行序列分析和系统发育分析。结果 7种斑叶兰属植物的ITS全长为700~702 bp,ITS1的长度为239~240 bp,ITS2为298~300 bp,而5.8 S的长度十分保守,均为162 bp;序列中检测到可变位点107个,其中信息位点34个。7种斑叶兰属植物的遗传距离为0.006~0.110,大花斑叶兰与高斑叶兰的遗传距离最大,亲缘关系最远,而斑叶兰和小斑叶兰的遗传距离最小,关系最近。结论克隆到7种斑叶兰属药用植物的ITS序列,它们信息位点丰富,这些位点可将7种植物完全区分。

Cloning and analysis of rDNA ITS sequences from seven kinds of medicinal plants in Goodyera L.

Objective To identify the medicinal plants in Goodyera L.at molecular level,cloning and sequence analysis of seven internal transcribed spacer (ITS) sequences from seven plant species of Goodyera L.were performed.Methods ITS sequences were cloned using PCR amplification,and sequence analysis,evaluation of genetic distance as well as construction of phylogenetic tree were conducted by bioinformatics software.Results Full ITS sequences of seven kinds of plants in Goodyera L.were 700-702 bp in length.The length of ITS1 and ITS2 were 239-240 bp and 298-300 bp,respectively,while 5.8S sequences were more conserved with identical length of 162 bp.Thirty-four parsimony information sites among 107 variable sites were detected in the sequence.Genetic distances among seven plant species of Goodyera L.were 0.006-0.110.The greatest genetic distances were observed between V.grypoceras and V.diffusa var. brevibarbata indicating the farthest of their relative distinct relationship,and the smallest existed between V.diffusa and V.acuminata revealing their closest relationship.Conclusion ITS sequences of seven kinds of medicinal plants in Goodyera L.are obtained with a result of rich information sites which could be used to distinguish these seven species completely.