Figure 2.

ESD7 is required to maintain high levels of the repressive mark H3K27me3 in discrete regions of the FT and SOC1 chromatin. (A and B) Levels of H3K27me3 on FT and SOC1 chromatin were examined after ChIP assays. Amplified regions are depicted below each loci; black boxes represent exons and black lines intron regions. Chromatin was extracted from pool samples of 9-day-old (WT and mutants in Col background) and 6-day old (WT and mutants in Ler background) seedlings grown under LD collected 4 h after dawn. ChIP was performed with αH3K27me3 antibodies. DNA fragments after chromatin immunoprecipitation (ChIP) were quantified by Q-PCR and subsequently normalized to ACT2 as internal control. Values shown are relative to input and are mean ± SD (n = 3). Asterisks indicate statistically significant differences (P < 0.05) according to Student's t-tests comparing mutants with WT. All comparisons were no significantly different except for FT Z6 region in esd7-1 in Ler background. (C) Western blotting from nuclei extracts showing that esd7 mutation does not alter the global levels of either H3K9me2 or H3K27me3 histone marks. (D and E) Levels of histone H3 present on FT and SOC1 chromatin in DNA pol mutants. Chromatin from WT, esd7-1 and icu2-1 mutant seedlings was immunoprecipitated against αH3 antibodies and the same regions of FT and SOC1 chromatin analyzed in panels 2A and B were amplified; the values were subsequently normalized to ACT2 as internal control. Levels shown are relative to input and are mean ± SD (n = 3). Asterisks indicate statistically significant differences (P < 0.05) according to Student's t-tests comparing mutants with WT.