甘薯IbOPR2基因启动子克隆及调控因子的筛选OA

Jasmonic acids(JAs),as endogenous plant hormones,play a crucial role in the plant response to salt stress.12-oxophytodienoate reductase(OPR),a key enzyme in JA biosynthesis,remains poorly understood in terms of its expression regulation.To identify transcription factors involved in regulating IbOPR2 expression,this study used the salt-tolerant sweetpo-tato cultivar'Haida 7791'to clone the promoter sequence of the IbOPR2 gene.Bioinformatics analysis revealed various cis-acting elements,and transcriptional activation assays confirmed promoter activity.Yeast one-hybrid(Y1H)screening was conducted to identify transcription factors interacting with the promoter,and point-to-point Y1H assays were used to validate specific binding.A 1964 bp promoter sequence upstream of IbOPR2 was successfully cloned,containing recognition motifs such as MYBHv1,MYB,and WRKY,along with stress-responsive elements(MYB,MYC)and MeJA-responsive elements,indicating strong tran-scriptional activation potential.Five candidate transcription factors—PHL7,ZFP16,SKIP11,TGA2,and ERF2—were identified using MYC and MeJA response elements as bait in Y1H assays.Follow-up point-to-point verification confirmed that IbPHL7,IbZFP16,and IbSKIP11 specifically bind to the IbOPR2 promoter.Dual-luciferase reporter assays further demonstrated that these three transcription factors could activate the IbOPR2 promoter.Moreover,qRT-PCR analysis showed that the expression of IbPHL7,IbZFP16,and IbSKIP11 is responsive to salt stress in sweetpotato.Taken together,these results suggest that these tran-scription factors may function as upstream regulators of IbOPR2,modulating its expression under salt stress conditions.This study represents the first identification of transcriptional regulators of sweetpotato IbOPR2,providing a foundation for further investigation into its regulatory mechanisms in response to salt stress.