广西植物2025，Vol.45Issue(5)：855-871,17.DOI:10.11931/guihaia.gxzw202412006
三脉水丝梨叶绿体基因组特征及系统发育分析
Chloroplast genomic characteristics and phylogenetic analysis of Sycopsis triplinervia
摘要
Abstract
Sycopsis triplinervia is an evergreen shrub in the genus Sycopsis(Hamamelidaceae).The phylogenetic position of Sycopsis has been a subject of debate,and its evolutionary relationships with closely related genera such as Distyliopsis and Distylium remain unclear.Here we sequenced and assembled its chloroplast genome and conducted comparative genomic and phylogenomic analyses together with publicly available Hamamelidaceae chloroplast genomes.The results were as follows:(1)The chloroplast genome of S.triplinervia was 159 375 bp in length and encoded 133 genes,including 8 rRNA genes,37 tRNA genes,87 protein-coding genes and 1 pseudogene.(2)A total of 33 interspersed repeats,39 tandem repeats and 82 simple sequence repeats(SSRs)were identified.(3)Codon usage was biased toward A/U endings.Nine optimal codons were detected,and natural selection was determined to be the main driver of codon usage bias.(4)Overall,the chloroplast genome of S.triplinervia was highly conserved relative to its close relatives.Fifteen highly variable regions were identified as potential markers for molecular identification in Sycopsis.(5)Phylogenetic analyses indicated that Hamamelidaceae was monophyletic,and Hamamelis,Parrotiopsis,Sycopsis,Distyliopsis,Parrotia,and Distylium formed a strongly supported monophyletic clade.Within this clade,several genera were closely related to each other,and S.triplinervia was sister to the remaining taxa.However,Sycopsis,Parrotia,Distyliopsis,and Distylium were each non-monophyletic.This study provides fundamental data and a valuable reference for further phylogenetic research on Hamamelidaceae.关键词
三脉水丝梨/叶绿体基因组/水丝梨属/金缕梅科/基因组系统学Key words
Sycopsis triplinervia/chloroplast genome/Sycopsis/Hamamelidaceae/phylogenomic phylogenetics分类
生物学引用本文复制引用
熊霜,周富琴,王仕东,李锐,王树宝,黄媛..三脉水丝梨叶绿体基因组特征及系统发育分析[J].广西植物,2025,45(5):855-871,17.基金项目
国家自然科学基金(32360065). （32360065）
