IEM of free PfRON2-HA merozoites (pre-invasion) dual labeled with immunogold anti-HA (18 nm) and rhoptry bulb marker RAP1 (12 nm). Scale bar = 0.2 µm. (B) IEM of free PFF0645c-HA merozoites (pre-invasion) dual labeled with immunogold anti-HA (18 nm) and rhoptry bulb marker RAP1 (12 nm). Scale bar = 0.2 µm. (C) Widefield IFA of E64-treated schizonts (to prevent egress – see Materials and Methods) labeled with anti-PfRh2, anti-PfRON4 and DAPI. Scale bar = 5 µm. (D–G) Independent replicate imaging of merozoites from (D) PfRON2-HA, (E) PfASP-HA (two classes of distribution seen), (F) RAP1 and (G) PFF0645c-HA mid-way through invasion colabeled with anti-PfRON4 and DAPI. Zuccala ES, Gout AM, Dekiwadia C, Marapana DS, Angrisano F, Turnbull L, Riglar DT, Rogers KL, Whitchurch CB, Ralph SA, Speed TP, Baum J. Subcompartmentalisation of proteins in the rhoptries correlates with ordered events of erythrocyte invasion by the blood stage malaria parasite. PLoS One. 2012 7(9):e46160