The Toxoplasma Protein ARO Mediates the Apical Positioning of Rhoptry Organelles, a Prerequisite for Host Cell Invasion

摘要: Members of the phylum Apicomplexa actively enter host cells by a process involving discharge apically localized microneme and rhoptry organelles. To unravel processes involved in organelle biogenesis, we focused on Toxoplasma gondii armadillo repeats only protein (TgARO), a conserved acylated homogenously anchored to membrane. Conditional disruption TgARO results random cytosolic dispersion rhoptries severe defect T. gondii invasion, with no effects intracellular growth or cell egress. Importantly, displacement upon ARO depletion can be functionally complemented wild-type but not an acylation mutant. interacts myosin F, inhibition actin polymerization function also dispersal, indicating that apical positioning is actomyosin-based process. Thus, mediates localization rhoptries, which specifically required for invasion.