摘要
【目的】为羊踯躅新优园艺品种的鉴定及不同地理分布的羊踯躅亲缘关系分析提供参考。【方法】以羊踯躅叶片为试验材料,通过高通量测序得到其叶绿体基因组序列,并对叶绿体基因组结构区和功能区域进行注释,分析密码子的偏好性及简单重复序列。【结果】羊踯躅叶绿体基因组序列属于典型的四段式结构,全长为197877 bp。其中大单拷贝区长度为110189 bp,小单拷贝区长度为26 bp,2个反向重复区(IRa区和IRb区)长度均为43831 bp,GC含量为36.00%。羊踯躅叶绿体基因组共注释到146个基因,分别是92个蛋白编码基因、8个rRNA基因和46个tRNA基因。基因功能主要包括光合作用、自我复制、其他功能以及未知功能4个大类,光合作用功能中光系统Ⅱ的亚基的相关基因数目最多,自我复制功能中tRNA基因数目最多。羊踯躅叶绿体基因中,32个密码子的相对使用度大于1,倾向于以A和U结尾。在羊踯躅叶绿体基因组的简单重复序列中,A/T和AT/AT占位点总数量的64.71%,羊踯躅叶绿体基因组富含AT。通过系统发育分析得出,羊踯躅是羊踯躅亚属的唯一物种,其与常绿杜鹃亚属的亲缘关系较近。【结论】在通过叶绿体基因序列构建得到的系统进化树中,杜鹃花科不同属、杜鹃属不同组的物种被区分开来;根据叶绿体基因组的序列,可以定位其在系统发育进化树中的位置,分析与其亲缘关系较近的杜鹃种。
【objective】The purpose of this paper is to provide theoretical guidance for the in-situ and ex-situ conservation of its germplasm resources.【Method】With the leaves of Rhododendron molle used as experimental material,analyzing the relative synonymous codon usage(RSCU)and simpel sequences repeat(SSR)by obtaining the chlorplast genome sequence of rhododendron by high-throughput sequencing and annotating the structural and functional regions of it.【Result】The chloroplast genomic sequence of R.molle was a typical four-segment structure with a full length of 197877 bp.Among them,the length of large single-copy region(LSC)was 110189 bp,the length of small single-copy region(SSC)was 26 bp.Also,the length of two reverse repetitive regions(IRa region and IRb region)were 43831 bp and the GC content was 36.00%.The chloroplast genome of R.molle was annotated with 146 genes,including 92 protein coding genes,8 rRNA genes and 46 tRNA genes.Gene function mainly includes four categories:photosynthesis,self-replication,other functions and unknown functions.In photosynthesis,the number of genes related toⅡsubunits of photosystem was the largest,and the number of tRNA genes in self-replication function was the largest.Further RSCU analysis of R.molle chloroplast gene showed that there were 32 codons RSCU>1,which tended to end with A and U.According to the analysis of all SSR loci,64.71%of all loci were A/T and AT/AT,and the chloroplast genome of R.molle was rich in AT.Through phylogenetic analysis,which was concluded that R.molle was the only species in the subgenus Pentanthera,and its genetic relationship was close to that of evergreen subgen.Hymenanthes.【Conclusion】By referencing the phylogenetic tree constructed from chlorplast gene sequence,it will be able to distinguish species from different genera in rhododendranceae and different groups of rhododendrons.Based on the chloroplast genome sequence,it will be able to locate the specific species’s position in the phylogenetic tree and analyze the rhododendron species closely related to it.
作者
吴林世
廖菊阳
刘艳
李巧云
王玲
张娟
宋胤
胡俊东
WU Linshi;LIAO Juyang;LIU Yan;LI Qiaoyun;WANG Ling;ZHANG Juan;SONG Yin;HU Jundong(Hunan Botanical Garden,Changsha 410116,Hunan,China;National Forestry grassland Rhododendron Engineering and Technology Research Center,Changsha 410116,Hunan,China)
出处
《经济林研究》
北大核心
2022年第1期123-131,共9页
Non-wood Forest Research
基金
中央财政林业科技推广示范资金项目(2020 XT 05号)
湖南省重点研发计划(2021NK2009)
湖南省林业局推广项目“观赏药用植物羊踯躅杜鹃繁育栽培技术推广示范”(202101)
湖南省新优杜鹃绣球等花灌木种质资源库项目(202109)。
