 The study shows that the toxoplasma gondigene regulator of cystogenesis 1-ROCY1 is sufficient for bradyzoid formation in vitro and in vivo, and its RNA binding domains are required to mediate this process. Female mice infected with Rosu1 parasites have reduced cyst burden, but viable parasites can still be cultivated from brain tissue for up to six months post infection. Despite defects in bradyzoid formation and oral infectivity, Rosu1 parasites were able to reactivate with similar timing and magnitude as wild type parasites for up to five months post infection, raising new questions about the persisting life-stage responsible for causing recrudescent disease. This article was authored by Sarah Elso Corborelli, Sarah M. Riley, Michael J. Holmes, and others.