桔梗科rps2基因簇断裂对进化速率的影响  

Effects of the broken rps2 gene cluster on evolutionary rates in Campanulaceae

作　　者：栗锦烨 平晶耀 崔贵峰 苏应娟[3,4] 王艇 Li Jin-Ye;Ping Jing-Yao;Cui Gui-Feng;Su Ying-Juan;Wang Ting(College of Life Sciences,South China Agricultural University,Guangzhou 510642,China;Nanzhao State-owned Forest Farms(Funiu Mountain National Nature Reserve Nanzhao Baotianman Administration in Henan),Nanzhao,Henan 474665,China;School of Life Sciences,Sun Yat-sen University,Guangzhou 510275,China;Research Institute of Sun Yat-sen University in Shenzhen,Shenzhen,Guangdong 518057,China)

机构地区：[1]华南农业大学生命科学学院,广州510642 [2]国有南召林场(河南伏牛山国家级自然保护区南召宝天曼管理局),河南南召474665 [3]中山大学生命科学学院,广州510275 [4]中山大学深圳研究院,广东深圳518057

出　　处：《植物科学学报》2023年第3期333-342,共10页Plant Science Journal

基　　金：国家自然科学基金项目(31770587)。

摘　　要：保守的rps2基因簇(rps2-atpI-atpH-atpF-atpA)在桔梗科的叶绿体基因组中发生了断裂。为探究该基因簇断裂后,相关基因的进化速率是否发生变化,本研究选取50种桔梗科植物和2种睡菜科植物的叶绿体基因组序列进行系统发育关系的构建,对rps2基因簇相关基因的进化速率、选择压力以及适应性进化过程进行分析。结果显示,桔梗科中rps2基因簇发生断裂的物种均来自风铃草亚科,且在系统发育树上组成单系分支;与未断裂物种相比,断裂物种中相关基因的进化速率均值降低;基因间的非同义替换速率存在显著差异。适应性进化分析中,位点模型在atpI和rps2基因中检测到正选择位点。本研究结果表明基因簇断裂可能具有系统发育意义,基因簇断裂后进化速率会发生改变,不同基因也经历了不同的进化历程。The conserved rps2 gene cluster(rps2-atpI-atpH-atpF-atpA)is broken in the chloroplast genome of Campanulaceae.To explore whether the evolutionary rates of the related genes changed after the cluster was broken,we selected the chloroplast genome sequences of 50 Campanulaceae and two Menyanthaceae species to construct their phylogenetic relationships,and further analyzed the evolutionary rate,selection pressure,and adaptive evolutionary process of the rps2 gene cluster-related genes.Results showed that all species with a broken rps2 gene cluster in Campanulaceae were from Campanuloideae and formed monophyletic branches on the phylogenetic tree.Compared with the unbroken species,the mean evolutionary rate of the related genes decreased in the broken species.There were significant differences in the nonsynonymous substitution rate between genes.In adaptive evolutionary analysis,the site model detected positive-selection sites in the atpI and rps2 genes.Our findings suggest that the fragmentation of the gene cluster holds phylogenetic implications,leading to alterations in evolutionary rates and diverse evolutionary trajectories among individual genes.

关 键 词：rps2基因簇 桔梗科 进化速率 选择压力 适应性进化 

分 类 号：Q943[生物学—植物学]