广西植物2026，Vol.46Issue(3)：492-506,15.DOI:10.11931/guihaia.gxzw202501026
钩藤钩发育相关SEPALLATA-like基因的克隆与表达分析
Cloning and expression analysis of hook development-related SEPALLA TA-like genes in Uncaria rhynchophylla
摘要
Abstract
The hook is a distinctive structure of the medicinal plant Uncaria rhynchophylla,and serves as its primary medicinal part.Although the hook and inflorescence are considered to be homologous organs,the developmental mechanism of the hook remains unclear.To investigate the origin and the developmental mechanism of the hook,this study cloned the complete coding sequences of three SEPALLATA(SEP)-like genes,belonging to the MADS-box transcription factor family,by using RT-PCR and RACE techniques.The functions of these SEP-like genes were preliminarily characterized through bioinformatic prediction,subcellular localization,transcriptional activation assays,and RT-qPCR methods.The results were as follows:(1)The full-length cDNA of the three genes,UrSEP1,UrSEP3.1 and UrSEP3.2,were 931,981,1 097 bp in length,which contained the coding sequences(CDS)of 738,726,729 bp,encoding 245,241,and 242 amino acid residues,respectively.All proteins contained conserved domains,including MADS domain,K-box,SEP Ⅰ and SEP Ⅱ motifs.(2)Phylogenetic tree analysis revealed that UrSEPs exhibit the closest relationship to CaSEPs from Coffea arabica.UrSEP1 clusters within the SEP 1/2 clade of the LOFSEP subgroup,while UrSEP3.1 and UrSEP3.2 belong to the SEP3 subgroup.(3)Subcellular localization showed that UrSEPs were all localized in the nucleus and confirmed the nuclear activity of UrSEPs.Transcriptional activation assays suggested that UrSEP1 and UrSEP3.2 might exhibit transcriptional activation activities,indicating that they can bind DNA directly.(4)Results of RT-qPCR revealed potential homology between hook and inflorescence,alongside developmental divergence.UrSEP3.1 and UrSEP3.2 showed higher transcriptional levels in hook than in root,stem or leaf,with similar expression patterns during hook and inflorescence development;the expression level of UrSEP1 peaked in hook bud,surpassing levels in other vegetative tissues and inflorescence bud,and displayed opposing expression patterns during hook versus inflorescence development.In summary,the three UrSEPs genes encode nuclear-localized proteins from SEP 1/2 and SEP3 clades,implicating their roles in hook development and early-stage fate divergence between hook and inflorescence.These results provide genetic insights into the origin of the hook and establish a foundation for elucidating the molecular mechanisms underlying hook morphogenesis in Uncaria rhynchophylla.关键词
钩藤/SEPALLATA-like/基因克隆/亚细胞定位/转录激活活性/表达分析Key words
Uncaria rhynchophylla/SEPALLATA-like/gene cloning/subcellular localization/transcriptional activation activity/expression analysis分类
农业科技引用本文复制引用
黄明慧,罗秋妹,刘畅,魏升华,李涛,桑思宏..钩藤钩发育相关SEPALLATA-like基因的克隆与表达分析[J].广西植物,2026,46(3):492-506,15.基金项目
贵州省科技计划项目(黔科合基础-ZK[2021]一般086) （黔科合基础-ZK[2021]一般086）
贵中医博士启动资金资助项目(贵中医博士启动[2019]40) （贵中医博士启动[2019]40）
贵中医学术新苗资助项目(贵科合学术新苗[2023]-17). （贵科合学术新苗[2023]-17）
