Fig. 6

The MPK3-HD2B module contributes to the regulation of H3K9 acetylation dynamics in response to flagellin. a Sixty percent of H3K9 flg22-induced hypo-acetylated genes are HD2B targets (left) compared with only 14% of H3K9 flg22-induced hyper-acetylated (right). b MPK3 and HD2B promote H3K9 deacetylation of hypo-acetylated genes after flg22 treatment. ChIP-qPCR assays on four selected loci using an anti-H3K9ac antibody were performed in WT and hd2b and mpk3 mutant seedlings either mock- or flg22-treated for 30 min. The four genes were hypo-acetylated after flagellin treatment in WT plants and this deacetylation failed to occur in the hd2b or mpk3 mutants. Asterisks indicate significantly different values (ANOVA test, p < 0.05). c HD2B is bound to hypo-acetylated genes after flg22 treatment. ChIP-qPCR assays with anti-GFP antibodies were performed on pHD2B::GFP-HD2B seedlings using oligonucleotides in the proximal promoter region of the four selected loci. IgG antibody was used as a negative control. Asterisks indicate significantly different values (Student’s t-test, p < 0.05). d MPK3 and HD2B are required for gene repression of hypo-acetylated genes after flg22 treatment. Expression of the four selected genes was analyzed by qRT-PCR in WT, hd2b, and mpk3 seedlings mock- or flg22-treated for 30 min. Genes were repressed in the WT but not in hd2b and mpk3 mutants. Asterisks indicate significantly different values (ANOVA test, p < 0.05)