腊肠树叶绿体基因组序列特征及其系统发育分析

The complete chloroplast genome of Cassia fistula L.and its phylogenetic analysis

目的获取腊肠树(Cassia fistula L.)叶绿体基因组信息特征,对其在决明属(Cassia Linn.)中的系统发育位置进行研究,为腊肠树有效的开发、保护和利用提供理论依据。方法使用Illumina测序技术对腊肠树进行测序,并结合生物信息学方法对其进行叶绿体基因组组装、注释和系统发育分析。结果腊肠树叶绿体基因组长度为161,724 bp,具有典型的四分体结构,总GC含量为36.1%,包含128个基因,其中83个蛋白质编码基因,37个tRNA基因和8个rRNA基因。系统发育分析表明,7个决明属物种被聚为3支,美丽决明S.spectabilis、望江南S.occidentalis、铁刀木S.siamea和决明S.tora聚为一支,腊肠树C.fistula与布鲁斯特决明C.brewsteri聚为一支,山扁豆Chamaecrista mimosoides单独聚为一支,且腊肠树与布鲁斯特决明C.brewsteri的亲缘关系最近。结论从叶绿体基因组系统发育的角度来看,本研究支持2010版的Flora of China的决明亚族植物种类的划分结论,决明属物种中的美丽决明S.spectabilis、望江南S.occidentalis、铁刀木S.siamea和决明S.tora应归为番泻决明属(Senna),腊肠树C.fistula应归为决明属(Cassia),山扁豆Ch.mimosoide应归为山扁豆属(Chamaecrista)。

Objective This study aims to obtain the information characteristics of the chloroplast genome of C.fistula,and to study its phylogenetic position in Cassia genus,so as to provide a theoretical basis for the effective development,protection and utilization of C.fistula.Methods The C.fistula was sequenced by Illumina sequencing technology,and its chloroplast genome was assembled,annotated and phylogenetic analyzed by combining bioinformatics methods.Results The chloroplast genome of C.fistula was 161,724 bp in length and had a typical tetrad structure.The total GC content is 36.1%.It contained 128 genes,including 83 protein coding genes,37 tRNA genes and 8 rRNA genes.The results of phylogenetic analysis showed that 7 species of Cassia genus were grouped into 3 branches,senna spectabilis,S.occidentalis,S.siamea.and S.tora.were clustered in a branche,C.fistula and C.brewsteri were clustered in a branche,and Chamaecrista mimosoides.was clustered in a branche.The phylogenetic relationship between C.fistula and C.brewsteri was the closest.Conclusion From the perspective of chloroplast genome phylogeny,this study supports the conclusion of the classification of Cassiinae plant species of Flora of China in the 2010 edition.Among the S.spectabilis,S.occidentalis,S.siamea and S.tora should be classified as Senna genus,the C.fistula should be classified as Cassia genus,and the Ch.mimosoide should be more appropriately classified as Chamaecrista genus.