广西植物2025，Vol.45Issue(9)：1654-1667,14.DOI:10.11931/guihaia.gxzw202412039
ERF-Ⅶ转录因子RAP2.12调控淹水诱导拟南芥幼苗花青素合成
ERF-Ⅶ transcription factor RAP2.12 regulates submergence-induced anthocyanin biosynthesis in Arabidopsis thaliana seedlings
摘要
Abstract
Submergence stress,a major environmental constraint in agriculture,causes oxygen deficiency in plant tissues,thereby impairing plant growth,development,and survival.One notable adaptive response of plants to submergence is the accumulation of anthocyanins—flavonoid pigments with strong antioxidant properties that help mitigate reactive oxygen species(ROS)-induced damage.These compounds also play important roles in stress signaling and metabolic reprogramming.Although enhanced anthocyanin accumulation under submergence has been observed in multiple plant species,the underlying regulatory mechanisms,particularly at the transcriptional level,remain poorly understood.To clarify the molecular mechanism of submergence-induced anthocyanin biosynthesis,this study investigated the role of ERF-Ⅶ(ethylene response factor group Ⅶ)transcription factors in Arabidopsis thaliana.Anthocyanin levels were measured in various genotypes exposed to submergence treatment conditions.In addition,protein-protein interaction assays,including yeast two-hybrid(Y2H)and bimolecular fluorescence complementation(BiFC),were conducted to examine physical interactions between ERF-Ⅶ members and known regulators of anthocyanin biosynthesis.In addition,to elucidate its regulatory pathway,a systematic analysis of the role of RAP2.12 in regulating anthocyanin biosynthesis was conducted at both genetic and molecular levels.The results were as follows:(1)Anthocyanin accumulation under submergence depended on MBW complex,composed of MYB,bHLH,and WD40 proteins,which served as a central regulatory hub in flavonoid biosynthesis.(2)RAP2.12 physically interacted with MYB75,MYB90,and MYB113,and these interactions synergistically activated the expression of anthocyanin biosynthetic genes such as DFR and LDOX,indicating a transcriptional co-activation mechanism.(3)The rap2.2 2.3 2.12 triple mutant exhibited reduced sensitivity to submergence-induced anthocyanin accumulation,while(MA)RAP2.12-HA overexpression lines showed hypersensitivity,indicating that RAP2.12 promotes anthocyanin biosynthesis under submergence and acts as a positive regulator in this stress-adaptive pathway.(4)Genetic analysis revealed that the regulatory function of RAP2.12 was primarily dependent on MYB transcription factors,as RAP2.12 alone could not activate downstream gene expression in the absence of functional MYB proteins.In conclusion,RAP2.12 regulates anthocyanin biosynthesis and accumulation in A.thaliana seedlings under submergence stress by physically interacting with MYB75.It enhances the transcriptional activity of the MBW complex,thereby promoting the expression of key structural genes in the anthocyanin biosynthetic pathway.These findings expand our understanding of the roles of ERF-Ⅶtranscription factors in plant adaptation to hypoxic environments.Furthermore,this work provides novel insights into how environmental signals are integrated through transcriptional regulators to coordinate secondary metabolism and stress responses.It also provides a theoretical basis for understanding the molecular mechanism of plant response submergence stress and crop breeding.关键词
拟南芥/淹水/花青素/RAP2.12/MYB75Key words
Arabidopsis thaliana/submergence/anthocyanin/RAP2.12/MYB75分类
农业科技引用本文复制引用
吴旻,都洁,胡彦如..ERF-Ⅶ转录因子RAP2.12调控淹水诱导拟南芥幼苗花青素合成[J].广西植物,2025,45(9):1654-1667,14.基金项目
国家自然科学基金面上项目(32270613). （32270613）
