园艺学报2026，Vol.53Issue(3)：735-748,14.DOI:10.16420/j.issn.0513-353x.2025-0309
天目地黄RcMYB4调控花青素合成的功能研究
Functional Study of RcMYB4 in Regulating Anthocyanin Biosynthesis in Rehmannia chingii
摘要
Abstract
Using Rehmannia chingii as the experimental material,a novel R2R3-MYB transcription factor gene was cloned from its corolla,with the resulting gene being systematically named RcMYB4.The open reading frame(ORF)of the gene spans 777 bp,encoding 258 amino acids residues.Quantitative real-time PCR(qRT-PCR)analysis demonstrated predominant expression of RcMYB4 in the corolla tube.Multiple sequence alignment of protein homologs revealed that RcMYB4 contain conserved domains of the S6 subfamily.Phylogenetic tree construction using the neighbor-joining method revealed that RcMYB4 groups with RcMYB1 from R.chingii and RgMYB42 from R.glutinosa,exhibiting the closest phylogenetic relationship.Transient expression assays in Nicotiana benthamiana indicated that heterologous expression of RcMYB4 activated anthocyanin biosynthesis,with co-expression of RcMYB4+RcANS significantly enhanced anthocyanin accumulation compared to single transformation of RcMYB4.Agrobacterium tumefaciens-mediated genetic transformation in R.glutinosa revealed that transgenic lines overexpressing RcMYB4 exhibited significantly increased anthocyanin accumulation in both callus tissues and leaves of tissue-cultured seedlings compared to wild-type controls.In potted nutrient soil-grown transgenic R.glutinosa,both leaves and petioles exhibited significantly increased anthocyanin accumulation compared to wild-type controls.Notably,only the OE7 transgenic line showed enhanced anthocyanin content in tuberous roots,reaching 4.01 times that of the wild-type control.Expression analysis of anthocyanin biosynthetic structural genes in RcMYB4-overexpressing R.glutinosa lines revealed significant upregulation of RgANS,RgCHS,RgF3H,and RgDFR in leaves across three transgenic lines,with OE7 exhibiting the most pronounced increases.In tuberous roots,these four structural genes were exclusively upregulated in OE7.These results demonstrate that RcMYB4 is a positive regulatory transcription factor that activates anthocyanin biosynthesis in Rehmannia chingii.关键词
天目地黄/RcMYB4/地黄/花青苷/异源表达Key words
Rehmannia chingii/RcMYB4/Rehmannia glutinosa/anthocyanin/heterologous expression分类
生物科学引用本文复制引用
杨雅贺,丁宁,郝秋雯,高俊鸽,张朋雨,胡靖翊,张重义,王丰青..天目地黄RcMYB4调控花青素合成的功能研究[J].园艺学报,2026,53(3):735-748,14.基金项目
国家自然科学基金面上项目(82373985) （82373985）
中央本级重大增减支项目(2060302) （2060302）
河南省高等学校重点科研项目(25A360031) （25A360031）
