Gene AP2III-3 Affects Stage Conversion in Toxoplasma Gondii

Toxoplasma gondii is an intracellular parasite that infects roughly 1/3 of the world’s population. T. gondii has primarily two stages in its life cycle: the tachyzoite and bradyzoite stage. In its tachyzoite stage, T. gondii replicates and infects quickly in its host cells. However, after a few weeks, due to the pressure of the host’s immune system, T. gondii transforms in a chronic, slow replicating stage, where it forms cysts inside of its host. The initiation of the bradyzoite induction is dependent on a set of early genes. Through microarray analysis and other computational assays, a subset of genes was found that was promoted and upregulated during the transformation of T. gondii from tachyzoite to bradyzoite stage. This work studies the effect of a single gene, AP2III-3, which is believed to promote bradyzoite differentiation in T. gondii. Through gene cloning and homologous recombination, we examine this gene and its ability to cause bradyzoite gene expression by knocking it out. As much is not known about the early bradyzoite stages, we hope this adds to our current knowledge of the bradyzoite stage and opens possibilities for potential treatments