Fig. 5: FL7 inhibits PP2Cs activity through an N terminal auxin canalisation domain.

a Verification of the interaction between FL7 and ABI1 by Y2H. Schematic diagram of ABI1, FL7 proteins, and related truncations is shown in the upper panel. b Inhibition of phosphatase activity of ABI1 by FL7 protein and related truncations. Recombinant ABI1 (2 µg) and FL7 or related truncation proteins (4 µg) were used for phosphatase activity assays. GST (4 µg) was used as a control. Substrate concentration was 100 µM. Data are means ± SD of three technical replicates (one-way ANOVA with Tukey’s test; P < 0.05). Experiments were performed three times with similar results. c Kinetic of ABI1 phosphatase activity in the presence of FL7N. The calculated Km of ABI1, ABI1 + FL7N, ABI1 + FL7N + ABA was 47.62 µM, 71.51 µM and 51.77 µM, respectively, and the Vmax was 5301 nmol/min, 3593 nmol/min and 3123 nmol/min, respectively. Data are means ± SD (n = 3). The experiments were performed three times with similar results. d Germination phenotypes of Col-0, fl7, gFL7N, gFL7C and OE-FL7N lines. The seeds were germinated on 1/2 MS medium without or with ABA for 7 days (left). Data are means ± SD of three biological replicates, with each replicate containing at least 30 seedlings (two-way ANOVA with Tukey’s test, P < 0.05). e ABA-promoted stomatal closure of Col-0, fl7, gFL7N and gFL7C lines. Data are means ± SD (two-way ANOVA with Tukey’s test, P < 0.05). Experiments were performed three times with similar results. f Drought phenotypes of Col-0, fl7, gFL7N, gFL7C and OE-FL7N lines. Data represent means ± SD from three biological replicates, with each replicate containing at least 20 plants (two-way ANOVA with Tukey’s test, P < 0.05). Source data are provided as a Source Data file.