不同种质来源孩儿参的rDNAITS区序列分析及鉴别  

Identification of Pseudostellaria heterophylla from different idioplasms by analysis of rDNA ITS sequences

作　　者：易骏[1] 廖芳平 郑伟文[3] 

机构地区：[1]福建教育学院理科部,福建福州350001 [2]福建中西医结合研究院,福建福州350122 [3]福建省农业科学院生物技术研究所,福建福州350003

出　　处：《中草药》2013年第10期1318-1322,共5页Chinese Traditional and Herbal Drugs

基　　金：福建高校服务海西建设重点项目(NO.5)

摘　　要：目的通过分析不同种质来源孩儿参ITS序列,为孩儿参种内鉴别提供DNA分子标记。方法利用特异性引物进行PCR扩增、克隆和测序,对孩儿参的rDNA ITS区间碱基序列进行测定,比较其差异。结果参试的9个不同种质来源孩儿参的整个ITS长度变异为623～624 bp;其中ITS1为224 bp,G+C量为52.91%～54.26%;5.8 SrDNA为155 bp,G+C量为54.49%～55.13%;ITS2为244～245 bp,G+C量为55.55%～56.41%。整个ITS区共有17个变异位点(2.72%),ITS1、ITS2和5.8S的变异位点分别为7、7和3个,不同种质来源孩儿参均有若干个特异性的单核苷酸变异位点;各样品的序列同源性均在99.9%以上;序列间的遗传距离为0.003～0.013。显示了不同产地、不同种质孩儿参的变异是不超过1个种的范围内的变异。结论可利用ITS区序列差异,鉴别不同种质来源的孩儿参。Objective To provide the DNA molecular marker for the identification of Pseudostellaria heterophylla from the different idioplasms by analysis of rDNA ITS sequences.Methods PCR amplification,cloning,and sequencing were carried out using specified primer,and the rDNA ITS base sequences were compared.Results The ITS mutation extension was 623—624 pb among nine idioplasms of P.heterophylla.Thereinto,the ITS-1 was 224 pb and its G ＋ C content was 52.91%—54.26%,the 5.8S rDNA was 155 bp and its G ＋ C content was 54.49%—55.13%,the ITS-2 was 244—245 bp and its G ＋ C content was 55.55%—56.41%.There were 17 mutation sites（2.72%） in the whole ITS sequences.There were 7,7,and 3 mutation sites in ITS1,ITS2,and 5.8S,respectively.The different idioplasms had a number of specific single nucleotide mutation sites.Their homologies with each other were upwards 99.9% and their sequence genetic distances were 0.003—0.013.These results showed that the mutation in species from different producing areas and idioplasms was within no more than one species.Conclusion The mutation of ITS sequences could be used to authenticate P.heterophylla from different idioplasms.

关 键 词：分子鉴定 孩儿参 ITS序列 序列分析 种质鉴别 

分 类 号：R282.12[医药卫生—中药学]