木犀科植物叶绿体基因组结构特征和系统发育关系

木犀科11属19个种叶绿体基因组的一般特征和变异特征的比较分析显示, 结果表明, 该科叶绿体基因组大小为154-165 kb, 其差异主要是大单拷贝(LSC)长度的差异所致。Jasminum属3个物种的叶绿体基因组长度与其余物种有较大差异, 该属clpP基因内含子和accD基因丢失。共线性分析表明, Jasminum属3个物种多个基因出现基因重排现象, 倒位可能是重排的主要原因。Jasminum属在IRb/SSC和SSC/IRa边界的基因均与其它物种不同; 重复序列与SSR数量检测结果表明, Jasminum属与其余物种在数量及重复长度上差异较大。基于CDS数据构建的系统发育树表明, Abeliophyllum distichum和Forsythia suspensa为木犀科中较早分化的类群。

Chloroplast Genome Structural Characteristics and Phylogenetic Relationships of Oleaceae

In this study, the chloroplast genomes from 19 species (11 genera) in Oleaceae were compared to reveal the general characteristics and structural variations. The chloroplast genome sizes in Oleaceae were 154-165 kb, and the differences were mainly caused by the length of large single-copy regions. The chloroplast genome sizes of 3 species from the genus Jasminum differed greatly from that for other species; in addition, the introns from the clpP and accD genes were lost in Jasminum. Synteny analyses showed several gene rearrangements in 3 Jasminum species that were probably caused by inversions. The boundary genes between IRb/small single copy (SSC) and SSC/IRa regions in 3 Jasminum species differed from others. Repeat sequences and simple sequence repeat detection demonstrated that Jasminum had significant differences in repeat number and repeat length as compared with other genera. On the basis of shared protein-coding genes among 19 species, Abeliophyllum distichum and Forsythia suspensa were the early-diverging clades in Oleaceae.