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Toxoplasma gondii chromatin remodeler SWI/SNF controls parasite division and stage specific gene expression

ABSTRACT: The SWI/SNF complex is evolutionarily conserved across species, initially identified in yeast, and later associated with various human cancers. In research on Toxoplasma gondii, this complex specifically creates nucleosome-free regions (NFRs) at the promoters of male gamete-specific genes, thereby activating their expression. Disruption of this complex results in the loss of male gametes. Although the SWI/SNF complex is relatively conserved across species, its specific role in T. gondii remains unclear. In this study, we first catalogued the core ATPase subunits of chromatin remodeling complexes and characterized the function of the SWI/SNF ATPase subunits TgSNF2a and TgSNF2b. We found that deletion of these two subunits severely impaired tachyzoite growth and altered the mode of division from endodyogeny to endopolygeny. Disruption of the complex led to a reduction in chromatin accessibility, suppressed stage-specific gene expression during the tachyzoite stage, and indirectly upregulated early endodyogeny stage (EES) genes by downregulating transcriptional repressors such as AP2XII-2 and AP2XII-5, and disrupting interactions with the MORC complex. Consequently, the knockout strains exhibited a shift in gene transcription toward the EES stage. These results provide new insights into the epigenetic regulation of sexual reproduction in T. gondii, offering potential strategies for controlling toxoplasmosis.

ORGANISM(S): Toxoplasma gondii

PROVIDER: GSE287537 | GEO | 2025/09/17

REPOSITORIES: GEO

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