FIG. 5.
Toxoplasma invasion. (A) Illustration of the critical events associated with host cell invasion. Secretion from the rhoptries is represented by the emptied vesicles and release of membranous material into the forming PV. As the parasite squeezes into the cell (as indicated by the constriction on the parasite body), a moving junction (MJ) forms between the parasite surface and host plasmalemma. (B) Still frames from a video of Toxoplasma invading a human fibroblast. The timing of the event is indicated in the lower right corner of each frame and was virtually complete 10 s after attachment. As in the cartoon, the constriction is apparent as the parasite crosses through the host cytoskeleton (indicated by arrowheads).