Fig. 7: Pst DC3000 employs AvrPtoB to suppress CYP707A3 expression and promote water-soaking under high humidity.
From: Humidity-driven ABA depletion determines plant-pathogen competition for leaf water
a Schematic overview of the experimental design for analyzing gene expression, ABA accumulation, water-soaking, and bacterial growth in Pst DC3000-inoculated leaves. Illustration of a syringe adapted from WDB Co., Ltd., Research Net (https://www.wdb.com/kenq/illust/syringe). b Expression levels of CYP707A3, CYP707A1, and NCED3 in Pst DC3000-inoculated leaves at 6 hours post-infiltration (hpi) under HH. Wild-type (WT) plants were infiltrated with the indicated Pst DC3000 strains (OD600 = 0.2), maintained under moderate humidity (MH) for 2 h, and then transferred to HH for 4 h. Bars represent means (n = 3). c ABA levels in Pst DC3000-inoculated leaves. WT plants were inoculated with the indicated Pst DC3000 strains as described in (b). Bars represent means (n = 6). d, e Representative images (d) and quantification (e) of water-soaking in Pst DC3000-inoculated leaves. WT and cyp707a1 cyp707a3 mutant plants were infiltrated with the indicated Pst DC3000 strains (OD600 = 0.2), maintained under MH for 2 h, and then transferred to HH for 20–22 h. Box plots represent the median, first and third quartiles, with whiskers showing the minimum and maximum values (n = 36; pooled from two independent experiments). f, g Disease symptoms (f) and bacterial growth (g) in Pst DC3000-inoculated leaves. WT and cyp707a1 cyp707a3 mutant plants were infiltrated with the indicated Pst DC3000 strains (OD600 = 0.0002), maintained under MH for 2 h, and then transferred to HH for 3 days. Bars represent means (n = 6). Sample size (n) in (b, c, g) and (e) indicate biological replicates and leaves, respectively. Different letters indicate statistically significant differences (P < 0.05; one-way ANOVA followed by Tukey’s test in (b, c); two-way ANOVA followed by Tukey’s test in (e, g). dpi days post-infiltration. Experiments in (b, f, g) were repeated twice with similar results. h Working model of CYP707A3-mediated water-soaking resistance and its suppression by Pst DC3000 via T3S effector AvrPtoB under high humidity.
