School of Ecology and Nature Conservation, Beijing Forestry University, Beijing 100083, China.
Int J Mol Sci. 2024 Jun 20;25(12):6786. doi: 10.3390/ijms25126786.
sensu lato () includes approximately 100 species that are mainly distributed in arid and semi-arid regions. species are ecologically valuable for their roles in windbreaking and sand fixation. However, the taxonomy and phylogenetic relationships of the genus are still unclear. In this study, we sequenced and assembled the chloroplast genomes of representative species of and reconstructed robust phylogenetic relationships at the section level. The chloroplast genome has lost the inverted repeat region and wascategorized in the inverted repeat loss clade (IRLC). The chloroplast genomes of the eight species ranged from 128,458 bp to 135,401 bp and contained 110 unique genes. All the chloroplast genomes have a highly conserved structure and gene order. The number of long repeats and simple sequence repeats (SSRs) showed significant variation among the eight species, indicating heterogeneous evolution in . Selective pressure analysis of the genes revealed that most of the protein-coding genes evolved under purifying selection. The phylogenetic analyses indicated that each section forms a clade, except the section , which was divided into two clades. This study elucidated the evolution of the chloroplast genome within the widely distributed genus The detailed information obtained from this study can serve as a valuable resource for understanding the molecular dynamics and phylogenetic relationships within .
广义的（）包括大约 100 个种，主要分布在干旱和半干旱地区。种在防风固沙方面具有生态价值。然而，属的分类学和系统发育关系仍然不清楚。在本研究中，我们对代表性物种的叶绿体基因组进行了测序和组装，并在节水平上重建了稳健的系统发育关系。叶绿体基因组失去了反向重复区，并被归类为反向重复缺失分支（IRLC）。八种物种的叶绿体基因组大小在 128458bp 到 135401bp 之间，包含 110 个独特的基因。所有的叶绿体基因组都具有高度保守的结构和基因顺序。八个物种之间的长重复和简单重复序列（SSR）的数量表现出显著的变异，表明在（）中存在异速进化。对基因的选择压力分析表明，大多数蛋白质编码基因在进化过程中受到纯化选择。系统发育分析表明，每个节都形成一个分支，除了节（），它被分为两个分支。本研究阐明了广泛分布的属内叶绿体基因组的进化。本研究获得的详细信息可以作为理解内分子动力学和系统发育关系的有价值的资源。
