Cao Zhengying, Yang Linyi, Xin Yaxuan, Xu Wenbin, Li Qishao, Zhang Haorong, Tu Yuxiang, Song Yu, Xin Peiyao
Southwest Research Center for Landscape Architecture Engineering, National Forestry and Grassland Administration, Southwest Forestry University, Kunming, China.
Key Laboratory of Forest Resources Conservation and Utilization in the Southwest Mountains of China Ministry of Education, Southwest Forestry University, Kunming, China.
Front Plant Sci. 2023 Jul 7;14:1205051. doi: 10.3389/fpls.2023.1205051. eCollection 2023.
The genus is considered to be one of the most enigmatic groups in Lauraceae, mainly distributed in tropical and subtropical regions of Southeast Asia. The genus contains valuable oilseed and medicinal tree species. However, there are few studies on the genus at present, and its interspecific relationship is still unclear. In order to explore the genetic structure and evolutionary characteristics of the chloroplast genome and to resolve the species relationships within the genus, comparative genomic and phylogenetic analyses were performed on the whole chloroplast genome sequences of 51 samples representing seven taxa. The whole chloroplast genome size ranged from 150,753-150,956 bp, with a GC content of 38.8%-38.9%. A total of 128 genes were annotated within the chloroplast genome, including 84 protein coding genes, 8 rRNA genes, and 36 tRNA genes. Between 71-82 SSRs were detected, among which A/T base repeats were the most common. The chloroplast genome contained a total of 31 preferred codons. Three highly variable regions, --, -, and -, were identified with Pi values > 0.004. Based on the whole chloroplast genome phylogenetic tree, the phylogenetic relationships among the seven taxa were determined. and were the most closely related species, and was identified as the most basal taxon. In this study, the characteristics and sequence variation of the chloroplast genomes of seven taxa were revealed, and the genetic relationship among the species was clarified. The results of this study will provide a reference for subsequent molecular marker development and phylogenetic research of .
该属被认为是樟科中最神秘的类群之一，主要分布在东南亚的热带和亚热带地区。该属包含有价值的油籽和药用树种。然而，目前对该属的研究较少，其种间关系仍不清楚。为了探索该属叶绿体基因组的遗传结构和进化特征，并解决该属内的物种关系，对代表7个该属分类群的51个样本的全叶绿体基因组序列进行了比较基因组学和系统发育分析。该属全叶绿体基因组大小在150,753 - 150,956 bp之间，GC含量为38.8% - 38.9%。该属叶绿体基因组共注释了128个基因，包括84个蛋白质编码基因、8个rRNA基因和36个tRNA基因。检测到71 - 82个简单序列重复（SSR），其中A/T碱基重复最为常见。叶绿体基因组共包含31个最优密码子。鉴定出3个高变区，即--、-和-，其Pi值> 0.004。基于全叶绿体基因组系统发育树，确定了7个该属分类群之间的系统发育关系。和是亲缘关系最近的物种，被确定为最基部的分类群。本研究揭示了7个该属分类群叶绿体基因组的特征和序列变异，明确了物种间的遗传关系。本研究结果将为该属后续的分子标记开发和系统发育研究提供参考。
