FRAP analysis of fluorescein-labeled glycophorin in control and parasitized erythrocytes. Aliquots of cultures of parasitized erythrocytes (approximately 5% parasitemia) were treated with fluorescein thiosemicarbazide to label glycophorin and then permeabilized with SLO. (A) Inset shows fluorescence images of an uninfected red blood cell (uRBC) and of an erythrocyte with a mature-stage parasite (iRBC) during a FRAP measurement. Scale bar is 2 μm. The graph shows the typical kinetics of fluorescence recovery into the bleached region for an uninfected erythrocyte (○) and for erythrocytes infected with mature-stage parasites (▵). Data points shown at negative times represent fluorescence intensities prior to the bleach event. Average mean D_L and f_mob values for uninfected erythrocytes and ring stage- and mature stage-infected erythrocytes obtained from a number of measurements are shown in panels B and C, respectively. Numbers in bars as defined in Figure 1B. Error bars represent standard error.