DCA1 acts as an interaction co-activator of DST.

(A) Schematic diagram of constructs used in Dual Luciferase assays. (B) Ratio of firefly luciferase (LUC) to Renilla luciferase (REN) activity in Arabidopsis protoplasts cotransformed with different reporter constructs and effectors shown in (A). The results show that DST acts as a transcriptional activator, while DCA1 enhances the transcriptional activation function of DST. Data represent means ± sd (n = 3). (C) Real-time PCR quantification of the expression of the DST downstream target gene Prx24 in ZH11 and dst. Data represent means ± sd (n = 3). (D) Real-time PCR quantification of the expression of Prx24 in Ni and dca1. Data represent means ± sd (n = 3). (E) EMSA of DST protein with DCA1 protein on biotin-tagged B3 DNA containing the DST binding site sequence. Triangles and asterisks indicate shifted bands and nonspecific binding, respectively. FP, free probe. Significant differences were determined using the Student’s t-test (**P <0.01).