多叶勾儿茶叶绿体基因组比较分析及系统发育研究

目的 研究勾儿茶属药用植物多叶勾儿茶Berchemia polyphylla及变种光枝勾儿茶B. polyphylla var. leioclada叶绿体基因组成及结构特征，同时为勾儿茶属系统发育及进化研究提供参考。方法 基于Illumina平台对勾儿茶属药用植物多叶勾儿茶及变种光枝勾儿茶进行叶绿体基因组测序，利用生物信息学对其序列进行组装、注释和特征分析，与同科小勾儿茶属、枣属、枳椇属、鼠李属、冀核果属等的叶绿体全基因组进行比较分析，确定其在鼠李科植物中系统发育位置。结果 多叶勾儿茶和光枝勾儿茶叶绿体基因组具有典型环状四分体结构，全长分别为161 185、161 210 bp，注释得到131个基因，其中蛋白质编码基因86个，37个tRNA基因和8个rRNA基因。勾儿茶属与鼠李科其它药用植物比较基因组学分析表明，勾儿茶属叶绿体基因组具有较高的保守性，叶绿体基因组之间没有重排或倒置，IR区序列变异最低，LSC区的变异程度最高，其中ndhA、ycf1、ycf3、rpl16、clpP以及atpF等基因的编码区存在差异，这些位点为勾儿茶分子鉴定提供新位点。系统发育树表明勾儿茶属与鼠李属及翼核果...

Comparative analysis and phylogeny of chloroplast genomes in Berchemia polyphylla

Objective To investigate the chloroplast structural characteristics of Berchemia polyphylla and B. polyphylla var. leioclada, so as to provide reference for the phylogeny and evolutionary study of Berchemia. Methods Ilumina sequencing platform was used to obtain the whole chloroplast genome sequences of B. polyphylla and B. polyphylla var. leioclada. The sequences were assembled, annotated and characterized by bioinformatics. The chloroplast genomes were compared and phylogenetic analysis was performed with the chloroplast genomes of Berchemiella, Ziziphus, Hovenia, Rhamnus and Ventilago of the same family to determine its phylogenetic position in Rhamnaceae. Results The chloroplast genomes of B. polyphylla and B. polyphylla var. leioclada had a typical circular tetrad structure, with the total length of 161 185 bp and 161 210 bp, respectively. A total of 131 genes were annotated, including 86 protein-coding genes, 37 tRNA genes and eight rRNA genes. The chloroplast genome of Berchemia was highly conserved by comparative genomic analysis with other genera in Rhamnaceae, without rearrangement or inversion between chloroplast genomes. The variation of IR region sequence was the lowest, and the variation degree of LSC region was the highest. The results of comparative genomics showed that the coding regions of ndhA, ycf1, ycf3, rpl16, clpP and atpF genes were different, which provided new loci for molecular identification of Berchemia. In the phylogenetic tree, B. polyphylla and B. polyphylla var. leioclada were sister groups, which can clearly reflect the genetic relationship. Furthermore, Berchemia was closely related to Rhamnus and Ventilago. Conclusion In this study, the chloroplast genome structure of Berchemia was analyzed, and the phylogenetic relationship among the genera of Berchemia was discussed, which laid a foundation for the study of taxonomic identification, phylogenetic evolution, resource exploitation and utilization of medicinal plants of Berchemia.