Figure 3.

IQM1 regulates JA biosynthesis and plant disease resistance through interaction with CAT2. A, Photographs of rosette leaves cut from 4-week-old wild-type, cat2-1, and cat3-1 plants at 3 d after infection with B. cinerea spores. B, Relative lesion sizes measured by ImageJ software at 3 d after inoculation with B. cinerea. The experiments were repeated at least three times, and similar results were obtained. The data are means ± sd of 10 infected leaves. C to E, Relative expression levels of CAT3 and CAT2 in iqm1-1 (C and D) and of IQM1 in cat2-1 (E) at 3 d after infection with B. cinerea. The differentially expressed genes were examined in leaves of 4-week-old plants harvested for RT-qPCR. ACTIN2 was used as the internal control. Independent biological assays were repeated three times, and similar results were obtained. Data from one representative replicate are shown. Values are means with sd from three technical measurements. F, Photographs of rosette leaves cut from 4-week-old wild-type, iqm1-1, cat2-1, and cat2/iqm1-1 double mutant plants at 3 d after infection with B. cinerea spores. G, Relative lesion sizes at 3 d after inoculation with B. cinerea. H, JA content of 4-week-old wild-type, iqm1-1, cat2-1, and cat2/iqm1-1 double mutant plants. The results were obtained from at least 30 independent plants for each genotype by mixed grinding. The data are means ± sd of three replicates. Asterisks represent significant differences compared with Col-0 (Student’s t test, **, P < 0.01).