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| 马先蒿属粗野-缘毛分支叶绿体基因组变异与演化研究 |
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王泽寻1,3, 刘 荣1,3, 吴 优1,3, 郁文彬2*, 王 红1*
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(1.中国科学院昆明植物研究所中国西南野生生物种质资源库,昆明 650201；2.中国科学院西双版纳热带植物园综合保护中心,云南 勐腊 666303； 3.中国科学院大学,北京 101408）
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| 摘要: |
| 异养植物对光合作用的依赖降低，其叶绿体基因组常表现出高度的异质性。为探究半寄生植物（异养植物的特殊类群）叶绿体基因组在近缘种间及种内的变异模式，该研究以马先蒿属（Pedicularis L.）粗野-缘毛分支（Rudes-Craspedotrichae Clade）为对象，对22个物种的39个个体的叶绿体基因组进行比较分析。结果表明：（1）粗野-缘毛分支为单系群，划分为8个亚分支。（2）该分支物种的叶绿体基因组整体结构较为保守，仅在亚分支3的长舟马先蒿（P. dolichocymba）和显盔马先蒿（P. galeata）中发现显著的IR区扩张。（3）2~7个基因（ccsA、ycf15、accD以及部分ndh基因）出现假基因化或丢失。（4）亚分支7的红毛马先蒿（P. rhodotricha）部分ndh基因（ndhA、D、F、G、I）表现出显著的种内变异。（5）该分支叶绿体基因组中鉴定出9个高变异区域；78个蛋白编码基因均受到纯化选择。该研究解析了马先蒿属粗野-缘毛分支叶绿体基因组特征，强调种内多居群取样研究对揭示半寄生植物叶绿体基因组演化的重要性，并为马先蒿属整合分类学研究提供了有价值的见解。 |
| 关键词: 半寄生植物，马先蒿属，系统发育，叶绿体基因组，异质性，演化 |
| DOI：10.11931/guihaia.gxzw202509003 |
| 分类号:Q949 |
| 基金项目:国家自然科学基金（32570243，32371700，32071670）。 |
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| Chloroplast genome variation and evolution in Rudes-Craspedotrichae Clade of Pedicularis |
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WANG Zexun1,3, LIU Rong1,3, WU You1,3, YU Wenbin2*, WANG Hong1*
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（1. The Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; 2. Center for Integrative Conservation, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, Yunnan, China; 3. University of Chinese Academy of Sciences, Beijing 101408, China)
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| Abstract: |
| The reduced dependence on photosynthesis in heterotrophic plants often leads to significant heterogeneity in their chloroplast genomes. However, the variation patterns of chloroplast genomes in hemiparasites (a specialized group of heterotrophic plants), particularly at inter- and intraspecific levels, remain to be further investigated. In this study, a comprehensive comparative analysis was performed on 39 chloroplast genomes from 22 species within Rudes-Craspedotrichae Clade of the genus Pedicularis. The results were as follows: （1）This clade is strongly supported as a monophyletic group, which can be resolved into 8 subclades.（2）The overall structure of chloroplast genomes in this clade was relatively conserved, with significant IR expansion detected only in P. dolichocymba and P. galeata of Subclade 3.（3）Pseudogenization or gene loss occurred in 2–7 genes, including ccsA, ycf15, accD, and several ndh genes.（4）Significant intraspecific variation was observed in several ndh genes (ndhA, D, F, G, I) of P. rhodotricha from Subclade 7.（5）Nine highly variable regions were identified in the chloroplast genomes of this clade, and all 78 protein-coding genes were found to be under purifying selection. This study elucidates the characteristics of chloroplast genomes in Rudes-Craspedotrichae Clade, highlights the necessity of multi-population sampling at the intraspecific level for understanding chloroplast genome evolution in hemiparasites, and provides valuable insights for subsequent integrative taxonomic research on the genus Pedicularis. |
| Key words: Hemiparasites, Pedicularis, phylogeny, chloroplast genome, heterogeneity, evolution |
