Mass spectrometry-based proteomic characterization of T. gondii AP2XI-2 and AP2XII-1 interactomes

Sexual reproduction of Toxoplasma gondii, which is restricted to the small intestine of felids, is sparsely documented in studies involving domestic cats, which also raises ethical concerns. Chromatin modifiers dictate the developmental fate of the parasite during its multistage life cycle, but their targeting to stage-specific cistromes is poorly described. AP2XII-1 and AP2XI-2, two transcription factors expressed in tachyzoites, a stage that causes acute toxoplasmosis, silence genes specific to merozoites, a developmental stage critical for sexual commitment and transmission to the next host, including humans. Their conditional and simultaneous depletion leads to a drastic change in the transcriptional program, promoting a complete transition from tachyzoites to merozoites. AP2XI-2 and AP2XII-1 likely synergize to suppress gene expression in tachyzoites, but their modus operandi is still enigmatic. We therefore characterized their interactomes.