Figure 6.

Application of Glutamate Triggers a Rapid Cytosolic Acidification without Noticeable Effects on the Cytosolic Redox State.

(A) and (B) Analyses of roots of 5-d-old Arabidopsis expressing PA-17-P2A-Grx1-roGFP2 (pH and E_GSH; n = 6; see [A]) and PA-17-P2A-roGFP2-Orp1 (pH and H₂O₂; n = 8; see [B]) in response to 1 mM glutamate (Glu; t = 0 min) and 100 µM H₂O₂ (t = 30 min). Images were acquired for 64 min at a frame rate of 10 min⁻¹. Average vertical response profiles of (top) fluorescence emissions (F) or emission ratios (R). (Middle) Signal changes (ΔF/F₀ or ΔR/R₀) normalized to 4-min average baseline recordings. An adjacent representative bright field (BF) root image is shown for orientation. (Bottom) Full image signal changes (mean ± sd). Note that experiments in (A) and (B) were acquired at different magnifications.

Representative experiments are provided as Supplemental Movies 6 and 7.