Figure 10.

MED8 positively regulates JA-mediated myrosinase activity. A and B, Myrosinase activity (A) and expression levels of TGG1 (B) of 21-d-old seedlings of the indicated genotypes after treating with 100 μM of MeJA for 24 h. Values are means ± sem of 8–16 plants. The experiments were repeated at least 3 times with similar results. Different letters represent significant differences (P < 0.05, Student’s t test). C, ChIP-qPCR assays showing that MED8 associates with the TGG1 locus. The chromatin of transgenic plants expressing ProMED8: MED8-GFP or 35S_pro: GFP was immunoprecipitated with an anti-GFP antibody, and 35S_pro: GFP plants served as control. Immunoprecipitated chromatin was analyzed by RT-qPCR using primers corresponding to the amplicons represented by the schematic diagram of TGG1 (Figure 7A). ChIP signal was displayed as the percentage of total input DNA. Means ± sem are relative values obtained from three technical replicates; different letters represent significant differences (P < 0.05, Student’s t test). D, FAMA affecting the recruitment of MED8 to the TGG1 locus. ChIP assays were performed as in (C), except that ProMED8: MED8-GFP, ProMED8: MED8-GFP/fama-2, and 35S_pro: GFP plants were treated with Control or 100 μM of MeJA for 30 min before cross-linking. E, MED8 affecting the recruitment of FAMA to the TGG1 locus. ChIP assays were performed as in (C), except that ProFAMA: FAMA-GFP, ProFAMA: FAMA-GFP/med8, and 35S_pro: GFP plants were treated with Control or 100 μM of MeJA for 30 min before cross-linking. D and E, Means ± sem are relative values obtained from three technical replicates; different letters represent significant differences (P < 0.05, Student’s t test).