Wu Lan, Wu Mingli, Cui Ning, Xiang Li, Li Ying, Li Xiwen, Chen Shilin
Key Laboratory of Beijing for Identification and Safety Evaluation of Chinese Medicine, Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, 100700, China.
Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100193, China.
Chin Med. 2021 Jul 5;16(1):52. doi: 10.1186/s13020-021-00460-z.
Although molecular analysis offers a wide range of options for species identification, a universal methodology for classifying and distinguishing closely related species remains elusive. This study validated the effectiveness of utilizing the entire chloroplast (cp) genome as a super-barcode to help identify and classify closely related species.
We here compared 26 complete cp genomes of ten Fritillaria species including 18 new sequences sequenced in this study. Each species had repeats and the cp genomes were used as a whole DNA barcode to test whether they can distinguish Fritillaria species.
The cp genomes of Fritillaria medicinal plants were conserved in genome structure, gene type, and gene content. Comparison analysis of the Fritillaria cp genomes revealed that the intergenic spacer regions were highly divergent compared with other regions. By constructing the phylogenetic tree by the maximum likelihood and maximum parsimony methods, we found that the entire cp genome showed a high discrimination power for Fritillaria species with individuals of each species in a monophyletic clade. These results indicate that cp genome can be used to effectively differentiate medicinal plants from the genus Fritillaria at the species level.
This study implies that cp genome can provide distinguishing differences to help identify closely related Fritillaria species, and has the potential to be served as a universal super-barcode for plant identification.
尽管分子分析为物种鉴定提供了广泛的选择，但一种用于分类和区分近缘物种的通用方法仍然难以捉摸。本研究验证了利用整个叶绿体（cp）基因组作为超级条形码来帮助鉴定和分类近缘物种的有效性。
我们比较了10种贝母属植物的26个完整cp基因组，包括本研究中测序的18个新序列。每个物种都有重复序列，cp基因组被用作完整的DNA条形码来测试它们是否能区分贝母属物种。
贝母属药用植物的cp基因组在基因组结构、基因类型和基因含量方面具有保守性。贝母属cp基因组的比较分析表明，与其他区域相比，基因间隔区高度分化。通过最大似然法和最大简约法构建系统发育树，我们发现整个cp基因组对贝母属物种具有很高的鉴别力，每个物种的个体都在一个单系分支中。这些结果表明，cp基因组可用于在物种水平上有效区分贝母属药用植物。
本研究表明，cp基因组可以提供区分差异，以帮助鉴定近缘贝母属物种，并且有潜力作为植物鉴定的通用超级条形码。
