Fig. 3.
(GlcNAc)8 induces [Ca2+]cyt elevations in guard cells in a CERK1-dependent manner. (A) Representative traces of fluorescence emission ratios (535/480 nm) showing transient [Ca2+]cyt elevations in Col-0 and cerk1-2 guard cells treated with 60 μM (GlcNAc)8. (B) Percentage of number of guard cells showing different number of transient [Ca2+]cyt elevations. (C) Area of transients of ratio (F535/F480) elevation in each guard cell showing [Ca2+]cyt elevations in B. Area of ratio transients per guard cell was calculated as the sum of areas of ratio transients above the baseline ratio in each guard cell and is considered proportional to the amount of Ca2+ mobilized. (D) Baseline ratio (F535/F480) in guard cells. (E) Traces of fluorescence emission in Col-0 guard cells treated with 60 μM (GlcNAc)8 in A. Note that fluorescence at 485 nm (white circles) decreases while fluorescence at 530 nm (black circles) increases, confirming fluorescence resonance energy transfer of the YC3.6 reporter. (GlcNAc)8 was added 5 min after the start of imaging. The average fluorescence ratio in the first 5 min of imaging was considered as the baseline ratio in D. [Ca2+]cyt elevations were counted when changes in fluorescence ratios were more than or equal to 0.1 U from the baseline ratio. Data are mean ± SEM. Different letters indicate statistical significance (P < 0.05, ANOVA with Tukey’s test). N.S., not significant.