Fig. 3

Treatment with HDAC inhibitor leads to hyperacetylation of heterochromatic blocks at sex chromosomes and decrease in methylation marks. Distribution of euchromatic marks H3K9ac and H4K8ac was analyzed by immunofluorescence staining. Female Microtus cabrerae cells were treated with or without HDACi LBH-589 (50 nM) for 24 h prior fixation. Acetylation levels were measured with a user-independent analysis: DNA (DAPI, blue), X*/X (H3K27me3/H3K9me3, green), acetylation (H3K9ac or H4K8ac, red). Arrows depict heterochromatic blocks at the H3K27me3 and H3K9me3 decorated X chromosomes. Mean acetylation signals for untreated cells (gray bar) and HDACi-treated cells (red bar) are shown. Sample sizes are indicated in the bar. Mean methylation levels are plotted for untreated cells (gray bar) and for HDACi-treated cells (green bar, red-framed). Scale bar 5 µm. Error bars demonstrate 95 Cl. ***P < 0.001