中药杜仲原植物的分子鉴定

Sequence analysis of chloroplast maturase K gene of Chinese medical plant Eucommia ulmoides

杜仲是我国特有贵重中药材,市场供不应求,各地出现许多伪品,为克服目前仅依据形态、显微特征及理化性状进行鉴别的不足,本研究旨在运用分子标记技术鉴定中药杜仲Eucommia ulmoides Oliv的真伪。采用PCR产物直接测序法测定杜仲原植物matK基因序列,通过Clustal软件将其与GenBank中同源序列进行排序比较,分析杜仲序列特征。结果:测定的杜仲matK序列长度为1140 bp,同源序列比较分析表明,杜仲matK序列中存在32个特异性位点,其中特异性A、T、C、G位点分别为8,2,11,11,序列中有一个GAC插入为杜仲所独有。matK基因是良好的分子标记,能够为杜仲原植物鉴定提供足够的特异性变异位点,matK基因序列的测序分析可成为杜仲正品鉴定的有效手段。

Duzhong (Eucommia ulmoides) is important Chinese medicine, due to it抯 high price and short supply, many duplicates are found in market. As Traditional taxonomy is difficult to ensure correct identification genuine Eucommia ulmoides, to develop an ultimate and definitive means for origin identification of genuine, the chloroplast matK gene was amplified by PCR using a consensus primer set and its nucleotide sequence was determined by PCR direct sequencing. The characteristic analysis of Eucommia ulmoides matk sequence was generated using Clustal aligned matK sequences of Apocynaceae and some related taxa, Celastraceae, and some most closely related matK sequences. 1140 bp matK gene sequences of Eucommia ulmoides were determined. Among 67 matK sequences analyzed, 32bp were unique in Eucommia ulmoides, including a 揋AC?indels. These characteristic nucleotide loci might be used to obtain species-specific RFLP pattern or to design species-specific primers to ultimate identify genuine Duzhong. Chloroplast matK gene sequences might be a good molecular marker to be used to identify traditional Chinese medical plants.