Figure 6. AprA prevents recognition of flagellin in Arabidopsis and prevents stomatal closure.

A. thaliana La-er seedlings were incubated with or without 500 nM flg22 or P. aeruginosa flagellin preincubated with 3 µg/ml AprA when indicated. (A). After treatment for 24 h, seedlings were stained for callose deposition by aniline blue and fluorescence was photographed under UV light. In the 3^rd row panels AprI was added before AprA treatment and in the bottom panels post AprA treatment (p.t.) of flagellin. (B) Examples of open (top), half open (middle) and closed (bottom) stomata, that were observed during the experiment. (C) Stomatal aperture on leaves of 5-week-old A. thaliana plants up to 40 minutes after treatment with P. aeruginosa PAO1 or isogenic aprA mutant strain (n = 108 to 224). Error bars indicate SEM. Asterisks indicate significant differences (Student's t-test; p<0.001) between WT and AprA mutant treated plants.