细茎石斛叶绿体全基因组序列特征及系统发育分析

细茎石斛是药用石斛的重要来源,也是正品枫斗的主要来源之一。本研究利用Illumina高通量测序技术对细茎石斛叶绿体全基因组进行测序,完成了其物理图谱绘制和基因组结构特征解析,并与近缘物种进行了比较和系统发育分析。细茎石斛叶绿体基因组全长为150 754 bp,两个反向互补重复区(IRs)长25 906 bp,大单拷贝区(LSC)和小单拷贝区(SSC)长度分别为84 818 bp和14 124 bp。共注释到123个基因,包括77个蛋白编码基因、38个tRNA基因和8个rRNA基因,其中17个基因含有内含子。生物信息学分析获得53个SSR位点,大多数位点具有A-T碱基偏好性。采用33条石斛属植物的叶绿体基因组序列构建系统发育树,结果显示细茎石斛复合种中的物种聚在同一个大支,说明其亲缘关系较近。本研究为细茎石斛的鉴定、细茎石斛复合种系统发育关系及其本草基因组学研究提供理论基础。

The characteristics of complete chloroplast genome sequence and phylogenetic analysis of Dendrobium moniliforme

Dendrobium moniliforme is an important source of Dendrobii Caulis and one of the main sources of authentic Fengdou. The complete chloroplast genome of D. moniliforme was sequenced using Illumina Hiseq technology and its gene map and genomic structure were analyzed. Then comparative and phylogenetic analysis of the complete chloroplast genomes of D. moniliforme and its related species were conducted. The chloroplast genome of D. moniliforme was 150 754 bp in length and had a typical quadripartite structure with a large single copy(LSC, 84 818 bp), a small single copy(SSC, 14 124 bp) and two inverted repeats(IRs, 25 906 bp each). A total of 123 chloroplast genes were annotated, including 77 protein-coding genes, 38 tRNA genes and 8 rRNA genes, of which 17 genes contained introns. Bioinformatics analysis identified 53 SSR sites, most of which had A-T base preference. A phylogenetic tree was constructed using the chloroplast genome sequences of 33 Dendrobium species. The results showed that Dendrobium complex species were clustered in a single large branch, indicating that they were closely related. This study provides a scientific basis for the identification of D. moniliforme and the phylogenetic relationship of D. moniliforme complex species necessary for Herbgenomics research.