ITS1作为DNA条形码用于冬虫夏草与其近缘种的鉴别

目的: 考察内转录间隔区1(ITS1)是否可以作为有效鉴别冬虫夏草的DNA条形码。方法: 提取冬虫夏草及常见伪品虫草的基因组DNA,以聚合酶链式反应(PCR)扩增并测序得到ITS序列,用CondonCode Aligner软件处理得到ITS1序列;从GenBank数据库下载冬虫夏草及常见伪品虫草的ITS1序列。用MEGA软件进行变异位点、Kimura-2-parameter(K-2P)遗传距离、Neighbor-Joining(N-J)进化树分析。结果: 冬虫夏草种内ITS1区存在5个多态性位点;最大种内距离0.039,小于最小种间距离(0.154);在系统进化树中,冬虫夏草聚为一支,可与虫草属其他种类虫草明确区分,Bootstrap值为100%。结论: ITS1可作为理想的DNA条形码用于冬虫夏草与常见虫草属伪品的鉴别。

Objective: To evaluate whether internal transcribed spacer 1(ITS1)could be used as the DNA barcode for the identification of Cordyceps sinensis.Methods: The genomic DNA of C.sinensis and its common adulterants from Cordyceps were extracted, the ITS sequences was obtained by polymerase chain reaction(PCR)amplification, and the sequences were processed with CondonCode Aligner software;the ITS1 sequences of C.sinensis and other common Cordyceps were downloaded from GenBank.The variation sites, Kimura-2-parameter(K-2P)distances and the Neighbor-Joining(N-J)tree were analyzed with MEGA software.Results: Five intraspecific variations were found within the ITS1region of C.sinensis. The maximum intraspecific K-2P distance C.sinensis was 0.039, which was smaller than the minimum interspecific K-2P distance(0.154).In the Neighbor-Joining(N-J)tree, C.sinensis was clustered as one branch with 100% Bootstrap values.Conclusion: ITS1 could serve as an ideal DNA barcode for the identification of C.sinensis.

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