Stevor overexpression is associated with a decrease in deformability of mature GIEs. (A) Immunofluorescence analysis of STEVOR expression in stage III and stage V GIEs from the wild-type (WT) and the SFM parasites. GIEs were stained with a pool of mouse polyclonal antibodies directed against STEVOR proteins or with anti–c-myc mAb followed by anti–mouse Alexa-488–conjugated IgG. Bars represent 2 μm. (B) Western blot analysis of STEVOR expression in stage III and stage V GIEs from the WT and the SFM parasites. Immunoblots were probed with a pool of mouse polyclonal antibodies directed against STEVOR proteins and with a mAb directed against HSP70. Vertical lines have been inserted to indicate a repositioned gel lane. (C) Retention in microsphilters of stages II, III, IV, and V GIEs from different WT P falciparum clonal lines (WT representing B10, H4, and 3D7GFP clones, in gray), from the SFM parasite line overexpressing a c-myc–tagged copy of the PFF1550w stevor gene (green) and the 2TMFM parasite line overexpressing a c-myc-tagged copy of the PFA0680c Pfmc-2TM gene (blue). ***Highly significant differences in retention rates (P < .01). Outliers are shown as open circles. NS indicates not significant.