Fig. 4: HSP90 provides plasticity to ABCB plasma membrane presence and auxin-controlled plant development.
From: HSP90 differentially stabilizes plant ABCB-type auxin transporters on the plasma membrane
a, b GDA treatment (5 μM) differentially destabilizes root tip ABCBs. Confocal imaging (a) and quantification of PM fluorescence signals in the root tip, corresponding to PM-specific analysis of manually traced ROIs precisely outlining the plasma membrane to extract membrane-localized signal was performed using the Zen Blue 2012 software package (b). Significant differences (p < 0.05) of means ± SE (n = 3 independent GDA treatments with 25–30 cells) were determined using Ordinary One-way ANOVA (Šídák’s multiple comparisons test) and are indicated by different lowercase letters; bars, 25 μm. c, d HSP90RNAi differentially destabilizes ABCBs in the root tip. Confocal imaging of HSP90RNAi (line 10H) (c) and quantification of PM fluorescence signals in root tips of HSP90RNAi lines 10H and 9.84, corresponding to PM-specific analysis of manually traced ROIs precisely outlining the plasma membrane to extract membrane-localized signal was performed using the Zen Blue 2012 software package (d). Significant differences (p < 0.05) of means ± SE (n = 4 independent experiments with 25–30 cells) were determined using Ordinary One-way ANOVA (Šídák’s multiple comparisons test) and are indicated by different lowercase letters; bars, 100 μm. e, f ABCBs own different sensitivities to Brefeldin A (BFA, 50 μM) in the root tip. Confocal imaging (e) and quantification of BFA body areas in the root tip (f). Significant differences (p < 0.05) of means ± SE (n = 3 BFA treatments with 20–30 cells) were determined using Ordinary One-way ANOVA (Tukey’s multiple comparisons test) and are indicated by different lowercase letters; bars = 50 μm. g Root elongation of abcb and twd1 mutants is differentially inhibited by GDA treatments (5 μM) in the order Wt ≪ abcb1 < abcb19 < abcb4 <twd1. Significant differences (p < 0.05) of means ± SE (n = 3 independent experiments, each with 10 roots) were determined using Ordinary One-way ANOVA (Šídák’s multiple comparisons test) and are indicated by different lowercase letters. h, i Meristem size (h) and cell number (i) of abcb and twd1 mutants is differentially inhibited by GDA treatments (5 μM) in the order Wt ≪ abcb1 < abcb19 < abcb4 < twd1. Significant differences (p < 0.05) of means ± SE (n = 3 independent experiments with each 10 roots) were determined using Ordinary One-way ANOVA (Tukey’s multiple comparisons test) and are indicated by different lowercase letters. Data are presented as box-and-whisker plots, where median and 25th and 75th percentiles are represented by the box itself and the middle line, respectively; means are indicated by a “+”. Source data are provided as a Source data file.
