铁冬青叶绿体全基因组及系统进化分析

Chloroplast Whole Genome of Ilex rotunda and Its Phylogenetic Analysis

铁冬青(Ilex rotunda)是具有多种应用价值的植物,为丰富其分子生物学信息及进一步明确系统位置,应用Illumina Novaseq 6000测序平台对其叶绿体基因组进行测序,组装获得了完整叶绿体基因组;并进行了基本特征分析、SSR特征分析,同时基于同源蛋白序列构建了包括铁冬青在内的33个物种的系统发育树。结果表明:(1)铁冬青叶绿体基因组大小为157,778 bp,其中IRs长度为26,124 bp,LSC长度为87,092 bp,SSC长度为18,438 bp,全基因组GC含量为37.70%,共编码131个基因;(2)共检测到131个SSR,其中大多数为单核苷酸SSR,共120个,占总体的91.60%;(3)系统发育分析表明铁冬青隶属于冬青亚属(Subgen.Ilex)单序冬青组(Sect.Lioprinus),与毛冬青(I.pubescens)和网脉多脉冬青(I.polyneura)亲缘关系较近。研究结果可为冬青科种质资源的鉴定,叶绿体基因组的利用及后续研究等提供理论依据。

Ilex rotunda is a plant of multiple applications.In order to get more molecular biological information and further clarify its phylogenetic position,the chloroplast genome was sequenced through Illumina Novaseq 6000 sequencing platform and whole chloroplast genome was assembled and obtained,then its basic characteristics and SSR characteristics were analyzed.And a phylogenetic tree was constructed based on homologous protein sequences of 33 species including I.rotunda.The results showed that:(1)The chloroplast genome of I.rotunda is 157778 bp in length,among which inverted repeat regions(IRs)were 26124 bp,a large single-copy region(LSC)was 87092 bp,small single-copy region(SSC)was 18438 bp,GC in the whole genome accounted for 37.7%and 131 genes were annotated,including 86 protein-coding genes,37 tRNA genes,and 8 rRNA genes.(2)131 SSR loci were detected,most of the which were single nucleotide SSR(120,91.60%).(3)Phylogenetic analysis showed that I.rotunda belonged to sect.Lioprinusis of subgen.Ilex,and it is closely related to I.pubescens and I.polyneura.The results can provide a theoretical basis for the identification of germplasm resources of the Aquifoliaceae family and the utilization and subsequent research of the chloroplast genome.