Figure 5.

BZR1 and GBF2 Synergistically Promote Guard Cell Starch Degradation and Stomatal Opening.

(A) BZR1 and GBF2 synergistically promoted stomatal aperture in intact leaves of the 4-week-old wild-type and the indicated mutant plants at the EoN and 1 h after white light exposure, as determined by light microscopy and digital image processing.

(B) Quantification of starch content in guard cells of intact leaves of the 4-week-old wild type and mutants at the EoN and 1 h after light exposure. Error bars indicate sd (n = 100 cells).

The ratio of stomatal aperture width to length and guard cell starch granules from at least 100 guard cells from 10 to 15 leaves of eight different plants were measured using ImageJ software. Three independent biological repeats were performed. Error bar indicates sd (n = 3 biological repeats). Different letters above the bars indicate statistically significant differences between samples (two-way ANOVA followed by a post hoc Tukey test, P < 0.05).