An apical protein, Pcr2, is required for persistent movement by the human parasite Toxoplasma gondii
Fig 5
Parasite replication is not affected, but egress is impaired in Δpcr2 parasites.
A. The average number of replications at 12, 24 or 36 hrs after infection in four independent experiments for RHΔhxΔku80 (WT), mEmeraldFP-Pcr2 knock-in (mE-Pcr2 KI), knockout (Δpcr2), and complemented (Comp) parasites. Error bars: standard error. B. Dot plots of time taken to disperse after treated with 5 μM A23187 for intracellular RHΔhxΔku80 (WT), mEmeraldFP-Pcr2 knock-in (mE-Pcr2 KI), knockout (Δpcr2), and complemented parasites. N: total number of vacuoles analyzed in 4 experiments, in which the parasite egress was monitored by time-lapse microscopy with 10-second intervals. *: Δpcr2 parasites in 37 out of 49 vacuoles failed to disperse from the parasitophorous vacuole during the 600 sec observation period. C. Images selected from time-lapse experiments of intracellular WT, mE-Pcr2 KI, Δpcr2, and complemented parasites treated with 5 μM A23187 (also see S2 Video). A23187 was added immediately before the beginning of the time-lapse. Red arrows indicate the positions of the parasitophorous vacuole in each image. Cyan arrows indicate some of the egressed parasites that have invaded into a new host cell.