Figure 8.

ABA inhibition of blue light-induced phosphorylation of H⁺-ATPase in wild-type (WT) and srk2e guard cells. A, Typical fluorescence images of stomata using anti-H⁺-ATPase in the epidermis from the wild type and the srk2e mutant. B, Quantification of fluorescence images of stomata. The fluorescence intensity of guard cells visualized with anti-pThr and Alexa Fluor 488-conjugated secondary antibody was quantified. Isolated epidermal fragments were illuminated with red light (RL) for 20 min and subsequently illuminated with red light or blue light with red light (RL + BL) for 2.5 min. Where indicated, 10 µm ABA was added immediately before the RL + BL treatment. Bars indicate averages of four independent experiments (n = 4; 120 total guard cells per bar). The asterisk indicates a significant difference (*α = 0.05) by Student’s t test. Error bars represent se. a.u., Arbitrary units.