Figure 3.

Histone H3 modification in the promoter of Arabidopsis defense genes upon plant treatment with SFN or BTH. Plants were sprayed with WP formulations of SFN (450 µm) or BTH (100 µm). Application of WP served as a control for these treatments. At 24 h after treatment, leaves were harvested and subjected to chromatin extraction, isolation, and immunoprecipitation with antibodies to the H3K4me3 (A, C, E, G, and I) or H3K9ac (B, D, F, H, and J) epitopes. DNA abundance in the precipitate was measured by qPCR with primers specific to WRKY6 (A and B), PDF1.2 (C and D), PR1 (E and F), RAB18 (G and H), or Rubisco (I and J). Data give the fold increase in amplicon abundance compared to a sample from untreated control plants. We analyzed the data for every given position of gene by one-way ANOVA followed by posthoc Student’s t test. Different letters denote statistically significant differences with 95% confidence. Data are means ± sd (n > 3).