PPLP2 Secretion in PfMTRAPKO Gametocytes (A) Fluorescence microscopy with anti-Band3 (green), anti-PPLP2 (red), and DAPI (blue) in wild-type and MTRAPKO NF54 P. falciparum sexual stages matured in vitro nonactivated or 2.5 hr postactivation. BF, brightfield. Scale bar, 5 mm. PfMTRAPKO had no impact in the time to gametocyte maturation nor in gametocyte yield in cultures. Gametocytes were stained with anti-Band3 for visualization

of the EM prior to activation or 2.5 hr after activation. While in wild-type parasites activated gametocytes formed gametes free from a surrounding EM after 2.5 hr, 89.5% of the PfMTRAPKO gametes, relative to the control, were wrapped inside an intact EM. (B) Fluorescence microscopy with anti-tubulin (green), anti-PPLP2 (red), and DAPI (blue) in wild-type and MTRAPKO NF54 P. falciparum sexual stages matured in vitro 25 min postactivation. BF, brightfield. Scale bar, 5 mm. This PPLP2 staining pattern was also observed in activated male gametocytes revealed by tubulin staining

of formed axonemes. While in exflagellated wild-type male gametocytes PPLP2 had been fully secreted, activated MTRAPKO male gametocytes formed a thick bundle of flagella, which are motile, surrounded by a periphery-associated PPLP2 staining pattern. Thus, MTRAP functions critically in the pathway that leads to both male and female gamete egress from the infected erythrocyte.

Bargieri DY, Thiberge S, Tay CL, Carey AF, Rantz A, Hischen F, Lorthiois A, Straschil U, Singh P, Singh S, Triglia T, Tsuboi T, Cowman A, Chitnis C, Alano P, Baum J, Pradel G, Lavazec C, Ménard R. Plasmodium Merozoite TRAP Family Protein Is Essential for Vacuole Membrane Disruption and Gamete Egress from Erythrocytes. Cell Host Microbe. 2016 20(5):618-630.