Liu Wen-Xiang, Li Guo-Bo, Zhou Zhuo, Chen Jia-Fu, Yu An-Min, Liu Ai-Zhong, Tian Bin, Ye Jun-Wei
National Plateau Wetlands Research Center, Southwest Forestry University, Kunming, China.
Key Laboratory for Forest Resources Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Southwest Forestry University, Kunming, China.
Front Plant Sci. 2025 May 1;16:1544247. doi: 10.3389/fpls.2025.1544247. eCollection 2025.
The taxonomy of Euphorbiaceae is extremely difficult, especially the phylogeny of closely related genera. In , which embraces an important non-food oil-seed crop worldwide, and are closely related genera based on molecular evidence (tribe Ricineae), however the intergeneric and interspecific relationship of the tribe is not well-resolved.
Plastome and transcriptome were sequenced and assembled before maximum likelihood and Bayesian inference phylogenetic trees were reconstructed. Plastome features and comparative analyses were conducted. Morphological traits of the tribe were explored as supplement to the molecular data.
The newly sequenced plastomes ranged from 167,327 to 190,093 bp with typical circular quadripartite structures. The longest genome of may due to higher number of simple sequence repeats. Natural selection pressure on chloroplast genes was relatively small and the tribe likely experienced a population contraction. The transcriptome assembly contig N50 of the tribe ranged from 1506 () to 2489 bp (). A total of 50,513 genes () to 78,048 genes () were detected, and the GC content varied between 38.17% () and 40.01% (). The three genera formed a well-supported monophyletic lineage, confirmed by different genomic data using different methods. and were supported to be closely related. In , diverged first and the divergence of and was followed. Further, morphological similarities supported the monophyletic lineage and intergeneric and interspecific relationship.
The relationship in the tribe Ricineae is clearly revealed by genomic and morphological data, providing a genetic basis for future comparative genomic investigations and phylogeny reconstruction of Euphorbiaceae.
大戟科的分类极其困难，尤其是近缘属的系统发育。在全球范围内包含一种重要非食用油籽作物的[具体属名未给出]中，基于分子证据（蓖麻族），[两个属名未给出]是近缘属，然而该族的属间和种间关系尚未得到很好的解决。
对质体基因组和转录组进行测序和组装，然后重建最大似然法和贝叶斯推断系统发育树。进行了质体基因组特征和比较分析。探索了该族的形态特征作为分子数据的补充。
新测序的质体基因组大小在167,327至190,093 bp之间，具有典型的环状四分体结构。[某个属名未给出]最长的基因组可能归因于较高数量的简单序列重复。叶绿体基因上的自然选择压力相对较小，该族可能经历了种群收缩。该族转录组组装重叠群N50范围从1506 bp（[某个属名未给出]）到2489 bp（[某个属名未给出]）。总共检测到50,513个基因（[某个属名未给出]）至78,048个基因（[某个属名未给出]），GC含量在38.17%（[某个属名未给出]）和40.01%（[某个属名未给出]）之间变化。这三个属形成了一个得到充分支持的单系类群，通过使用不同方法的不同基因组数据得到证实。[两个属名未给出]被支持为密切相关。在[某个属名未给出]中，[某个属名未给出]首先分化，随后是[两个属名未给出]的分化。此外，形态相似性支持了单系类群以及属间和种间关系。
蓖麻族中的关系通过基因组和形态数据得到了清晰揭示，为未来大戟科的比较基因组研究和系统发育重建提供了遗传基础。
