Fig. 3. H3K18 methylation is dynamic across stage transitions.

a Differentiation to merozoites led to a decrease of H3K18me1 in parasite nuclei Immunofluorescence analysis of T. annulata infected macrophages TaC12, at 37 °C (macroschizont) and after merogony induction for 8 days at 41 °C. Host and parasite nuclei were stained with DAPI (grey) and with a specific antibody for H3K18me1 (red). The yellow box shows a zoom of merogony. Leica microscope, ×100, Scale bar = 5 μm. The right panel shows quantification of immunofluorescence intensity of H3K18me1 (red) compared to DNA (grey), along the yellow cross-section line, showing reduced staining in merozoites. This experiment was performed three times independently with similar results. Immunofluorescence replicates are included in the Source Data file. b Changes in the level of Histone methylation and acetylation upon treatment with inhibitors of epigenetic enzymes. Fluorescence intensity quantification of the parasite histone marks H3K18me1, H3K18ac, H3K4me3 or H3K36me3 in TaC12 cells treated with either KDMi (histone demethylase inhibitor) or KDACi (histone deacetylase inhibitor). For all experiments n = 3 biologically independent experiments that represent the mean of intensity of 50 cells per condition for each replicate. Error bars represent the mean value ± SD. Statistical Dunnett test multiple comparisons is two-sided with ns (not statistically significant) of K18m p = 0.2979/ns of K18ac p = 0.2435/ns of K4 p = 0.5060/ns of K36 p > 0.9999/****p = 0.0001.