Figure 5

Exl1 activity protects from pathogens challenge in different hosts. (A) Maceration levels of celery petioles challenged with P. brasiliense BF45, 24 h after previous infiltration with buffer (Mock), or 3.7 μM pure Exl1 (WT), or expansin inactive D83A, and Y125A/W126A/Y157A (YWY). Box plots of three independent experiments (n = 35); significance p < 0.001 (**) was calculated with Kruskall-Wallis tests for non-parametric data. (B) Likewise, incidence of Arabidopsis thaliana leaf maceration levels challenged with P. brasiliense BF45, 24 h after previous infiltration with buffer (#1 bars), or 3.7 μM pure Exl1 (#2 bars), B. subtilis EXLX1 (#3 bars), D83A mutant (#4 bars), and YWY (#5 bars), over a 72-h period. An example of protected (Exl1) or macerated (Mock) leaves is shown on the right. Error bars indicate the +/− standard deviation of the average across at least three independent experiments (n = 105); significance p < 0.01 (*) was calculated according to a Kruskall-Wallis test for non-parametric data. (C) Dose-dependent protection conferred by infiltrated Exl1 in A. thaliana leaves treated 24 h previously, challenged with P. brasiliense BF45. Error bars indicate the +/− standard deviation of the average across at least three independent experiments (n = 60); significances p < 0.01 (*) and p < 0.0001 (***) were calculated according to a Kruskall-Wallis test for non-parametric data. (D) Exl1 protection to infection 24 h after previous incubation with the pathogenic fungus Botrytis cinerea. An example of protected (Exl1) or infected (Mock) leaves is shown on the right. Box plots of at least three independent experiments (n = 43); significance p < 0.00001 (****) was calculated according to a Mann-Whitney test for non-parametric data.