AUTHOR=Xu Kai-Ling , Zhang Zhong-Mou , Fang Wen-Liang , Wang Ya-Dan , Jin Hong-Yu , Wei Feng , Ma Shuang-Cheng 

TITLE=Comparative analyses of complete chloroplast genomes reveal interspecific difference and intraspecific variation of Tripterygium genus

JOURNAL=Frontiers in Plant Science

VOLUME=14

YEAR=2024

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2023.1288943

DOI=10.3389/fpls.2023.1288943

ISSN=1664-462X

ABSTRACT=<p>The genus <italic>Tripterygium</italic> was of great medicinal value and attracted much attention on the taxonomic study using morphological and molecular methods. In this study, we assembled 12 chloroplast genomes of <italic>Tripterygium</italic> to reveal interspecific difference and intraspecific variation. The sequence length (156,692–157,061 bp) and structure of <italic>Tripterygium</italic> were conserved. Comparative analyses presented abundant variable regions for further study. Meanwhile, we determined the <italic>ndhB</italic> gene under positive selection through adaptive evolution analysis. And the phylogenetic analyses based on 15 chloroplast genomes supported the monophyly of <italic>Tripterygium hypoglaucum</italic> and the potential sister relationship between <italic>Tripterygium wilfordii</italic> and <italic>Tripterygium regelii</italic>. Molecular dating analysis indicated that the divergence time within <italic>Tripterygium</italic> was approximately 5.99 Ma (95% HPD = 3.11–8.68 Ma). The results in our study provided new insights into the taxonomy, evolution process, and phylogenetic construction of <italic>Tripterygium</italic> using complete plastid genomes.</p>