Figure 5.

ERF11 repressed, whereas RGA induced, transcription of the bHLH137 promoter in tobacco transient expression assay by agroinfiltration. A, Schematics of the normalization control, reporter, and effector constructs. 35S:Renilla LUC (rLUC) served to normalize transformation efficiency. In the reporter constructs, the firefly LUC gene (fLUC) was placed under the control of different promoters of RGA target genes (bHLH137, bHLH154, and SCL3). 35S:RGA and 35S:ERF11 served as two effector constructs, respectively. The positions of two modified GCC box sequences in bHLLH137 promoter are labeled by asterisks: AGCCGCT at –2 kb and ACCCGCC at –0.2 kb. The empty effector vector was used as a negative control. B, RGA induced expression of all three target gene promoters, whereas ERF11 only repressed bHLH137 expression. Each reporter construct and the 35S:rLUC construct were introduced into tobacco leaves in the presence of the empty effector constructs (Control) or 35S:RGA and/or 35S:ERF11 (with the same molar ratios) by agroinfiltration. The relative fLUC activity (normalized by rLUC activity) in the empty effector control was set to 1. Data represent the average value ± se of eight biological replicas. Different letters above the bars indicate significant difference (P < 0.01).