FIGURE 2:

EH domain proteins regulate integrin β1 and TfnR endocytosis. (A–C) Control and siRNA-treated HeLa cells were incubated with anti–integrin β1 (A) or anti-TfnR antibody (B) for 30 min at 4°C, followed by warming at 37°C for 30 (β1) or 5 min (TfnR). (D–G) Control and EH domain–deficient HeLa cells were incubated with anti–integrin β1 (D) or anti-TfnR antibody (E) for 30 min at 4°C and then warmed to 37°C for the indicated times in the presence of 2 μM Primaquine. Surface antibody was removed by acid stripping, and internalized antibody was detected. (A, B, D, E) Z-projections of the entire cell. (C, F, G) Pixel intensities measured by ImageJ. Mean values and standard errors of internalized receptor after normalizing with surface receptor at time = 0 are shown. Approximately 15 cells/treatment from three independent experiments were analyzed. ^#p < 0.05, *p < 0.01, **p < 0.001 by t test. Bar, 10 μm.