SLR1 represses the transcriptional activity of UDT1 and TDR via physical sequestration, and GA alleviates this repression. A, EMSA showing that direct binding of UDT1 and TDR to the CP1 promoter is inhibited by the addition of increasing amounts of recombinant GST-SLR1 protein. Increasing amounts of GST protein were used as a negative control. B, Schematic diagrams of the effector and reporter plasmids used in the transient assay in rice protoplasts. C, Relative LUC activity in rice protoplasts co-transfected with the reporter and different combinations of effectors. Relative LUC activity was calculated as the ratio between firefly LUC and REN LUC. Data are shown as means ± se (n = 3). Each dot represents the result from one biological replicate. Significant differences are indicated by different lowercase letters (P < 0.05, one-way ANOVA with Tukey’s significant difference test). D, Relative CP1 expression levels in developing panicles of LJ11 and ga20ox1 plants grown under NC. Data are shown as means ± se (n = 3). E, Time course of relative CP1 expression levels in panicles of the cultivar LJ11 exposed to a 15°C cold treatment during the booting stage. The expression level on day 0 was set to 1. Data are shown as means ± se (n = 3). F, Relative CP1 expression levels in developing panicles of LJ11 plants grown under LT treatment with or without GA3 application. Data are shown as means ± se (n = 4). G, Relative CP1 expression levels in developing panicles of LJ11 and wrky53 plants grown under NC or after 4 days of LT treatment. Data are shown as means ± se (n = 3). Each dot represents the result from one biological replicate. P-values were calculated by Student’s t test: **P < 0.01 and *P < 0.05.