Dynamic methylation of histone H3K18 in differentiating Theileria parasites

Abstract Lysine methylation on histone tails impacts genome regulation and cell fate determination in many developmental processes. Apicomplexa intracellular parasites cause major diseases they have developed complex life cycles with fine-tuned differentiation events. Yet, apicomplexa genomes few transcription factors little is known about their epigenetic control systems. Tick-borne Theileria species relatively small, compact a remarkable ability to transform leucocytes bovine hosts. Here we report enriched H3 lysine 18 monomethylation (H3K18me1) the gene bodies of repressed genes macroschizonts. Differentiation merozoites (merogony) leads decreased H3K18me1 parasite nuclei. Pharmacological manipulation H3K18 acetylation or impacted expression stage-specific genes. Finally, identify SET-domain methyltransferase (TaSETup1) that can methylate represses expression. Thus, emerges as an important mark which controls stage parasites.