Control of gene expression is crucial for parasite survival and is the result of a series of processes that are regulated to permit fine-tuning of gene expression in response to biological changes during the life-cycle of apicomplexan parasites. Control of mRNA nuclear export is a key process in eukaryotic cells but is poorly understood in apicomplexan parasites. Here, we review recent knowledge regarding this process with an emphasis on T. gondii. We describe the presence of divergent orthologs and discuss structural and functional differences in export factors between apicomplexans and other eukaryotic lineages. Undoubtedly, the use of the CRISPR/Cas9 system in high throughput screenings associated with the discovery of mRNA nuclear export complexes by proteomic analysis will contribute to identify these divergent factors. Ligand-based or structure-based strategies may be applied to investigate the potential use of these proteins as targets for new antiprotozoal agents.

Faculty of Science University of South Bohemia České Budějovice Czech Republic

Institute of Parasitology Biology Center Czech Academy of Sciences České Budějovice Czech Republic

Instituto Carlos Chagas FIOCRUZ Rua Algacyr Munhoz Mader 3775 CIC Curitiba PR 81350 010 Brazil

UMR BIPAR Animal Health Laboratory ANSES INRA ENVA Maisons Alfort Cedex France

University of Lille CNRS Inserm CHU Lille Institut Pasteur de Lille U1019 UMR 8204 CIIL Centre d'Infection et d'Immunité de Lille F 59000 Lille France

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Evolution and diversification of the nuclear pore complex