赤水金钗石斛rDNAITS序列分析

目的:对赤水金钗石斛ITS序列进行序列测定与分析,探讨赤水金钗石斛在ITS片段上的遗传特征,提高道地药材赤水金钗石斛在分子水平的鉴定标准。方法:用特异引物进行PCR扩增,扩增产物纯化后用双脱氧终止法(Sangerdideoxy)测序。结果:通过与基因库登录的金钗石斛ITS对照,赤水金钗石斛ITS1与ITS2序列的起止范围分别为1~231 bp和395~636 bp。赤水金钗石斛在8位缺失碱基C,在12位缺失碱基A,在82位为碱基A;据此,以NJ法(邻接法)构建了系统树。测序结果登录基因库,序列号:EF618732。结论:金钗石斛ITS1序列基因多态性比ITS2序列更显著;该实验结果为道地药材赤水金钗石斛的物种鉴定补充了新的遗传数据。

Analysis of Chishui Dendrobium nobile based on rDNA ITS variation

Objective:To study the genetic character of ITS sequence of Chishui D.nobile and obtain a good molecular marker for authentication of Chishui D.nobile,the rDNA ITS region sequences were investigated by the methods of DNA sequencing.Methods: The nuclear ribosomal ITS was amplified with primes P1 and P2,and then send the products to the sequencing company. Results: By contrasting with Genbank,sequence analysis showed that the range of ITS1 was from 1 to 231,ITS2 from 395 to 636.Base C in site 8,Base A in site 12,Base A in site 82,were missed in ITS sequence of Chishui D.nobile.According the result,phylogenetic tree based on ITS sequences data was reconstructed by Neighbor joining method.The result of sequencing has been submitted to Genbank.Accession number is EF618732. Conclusion: The sequence of ITS1 contained more variable sites and potential informative sites than that of ITS2 among D.nobile species.By our result for Chishui D.nobile,New genetic data were also supplied to authenticate chishui D.nobile.