Journal Article

Toxoplasma gondii ROP16 kinase silences the cyclin B1 gene promoter by hijacking host cell UHRF1-dependent epigenetic pathways

Konjic, Ana, Pfaff, Alexander W., Viville, Stéphane, Lennon, Sarah, Candolfi, Ermanno, Brunet, Julie, Rohr, Olivier, Sabou, Marcela, Doderer-Lang, Cécile, Kubina, Sophie, Leyer, Caroline, Cianférani, Sarah

2020

Overview

Toxoplasmosis, caused by the apicomplexan parasite Toxoplasma gondii, is one of the most common infections in the world due to the lifelong persistence of this parasite in a latent stage. This parasite hijacks host signaling pathways through epigenetic mechanisms which converge on key nuclear proteins. Here, we report a new parasite persistence strategy involving T.   gondii rhoptry protein ROP16 secreted early during invasion, which targets the transcription factor UHRF1 (ubiquitin-like containing PHD and RING fingers domain 1), and leads to host cell cycle arrest. This is mediated by DNMT activity and chromatin remodeling at the cyclin B1 gene promoter through recruitment of phosphorylated UHRF1 associated with a repressive multienzymatic protein complex. This leads to deacetylation and methylation of histone H3 surrounding the cyclin B1 promoter to epigenetically silence its transcriptional activity. Moreover, T.   gondii infection causes DNA hypermethylation in its host cell, by upregulation of DNMTs. ROP16 is already known to activate and phosphorylate protective immunity transcription factors such as STAT 3/6/5 and modulate host signaling pathways in a strain-dependent manner. Like in the case of STAT6, the strain-dependent effects of ROP16 on UHRF1 are dependent on a single amino-acid polymorphism in ROP16. This study demonstrates that Toxoplasma hijacks a new epigenetic initiator, UHRF1, through an early event initiated by the ROP16 parasite kinase.

• Publisher: Springer International Publishing,Springer Nature B.V,Springer Verlag
• Subject: Amino acids / B1 gene / Biochemistry / Biomedical and Life Sciences / Biomedicine / CCAAT-Enhancer-Binding Proteins - genetics / CCAAT-Enhancer-Binding Proteins - metabolism / Cell Biology / Cell cycle / Cell Cycle Checkpoints / Cell Line / Cellular Biology / chromatin / Chromatin remodeling / Cyclin B1 / Cyclin B1 - genetics / Cyclin B1 - metabolism / cyclins / Deacetylation / Deoxyribonucleic acid / DNA / DNA hypermethylation / DNA methylation / Epigenesis, Genetic / Epigenetics / genes / Histone H3 / Histones / Host-Parasite Interactions / Humans / Immunity / Kinases / Life Sciences / Original / Original Article / Parasites / Phosphorylation / Polymorphism / Promoter Regions, Genetic / Protein-Tyrosine Kinases - metabolism / Proteins / Protozoa / Protozoan Proteins - metabolism / rhoptry / Rhoptry protein / Signal transduction / Signaling / Stat6 protein / Toxoplasma - physiology / Toxoplasma gondii / Toxoplasmosis / Toxoplasmosis - genetics / Toxoplasmosis - metabolism / transcription (genetics) / Transcription factors / Ubiquitin / Ubiquitin-Protein Ligases - genetics / Ubiquitin-Protein Ligases - metabolism