Figure 3
Post-endocytic trafficking of EGFR in RBE and MMNK-1 cells. (A) Distribution of EGFR (Alexa Fluor 488) and Early endosome antigen 1 (EEA-1) (Alexa Fluor 555) in RBE and MMNK-1 cells before and after 0.5 and 1 hr of EGF stimulation as obtained by immunofluorescence. White arrows show points of colocalization. Scale bars: 10 μm. (B) Distribution of EGFR (Alexa Fluor 555) and Lysosomal-associated membrane protein-1 (LAMP-1) (Alexa Fluor 488) in RBE and MMNK-1 cells before and after 0.5 and 1 hr of EGF stimulation as obtained by immunofluorescence. White arrows show points of colocalization. Scale bars: 10 μm. (C) Left: colocalization rate between EGFR and EEA-1 in RBE cells (black columns) and MMNK-1 cells (white columns) before and after 0.5, 1, and 2 hr of EGF stimulation. Right: colocalization rate between EGFR and LAMP-1 in RBE cells (black columns) and MMNK-1 cells (white columns) before and after 0.5, 1, and 2 hr of EGF stimulation. Values are the percentage of the integrated density of EEA-1 or LAMP-1-colocalizing EGFR compared to that of total EGFR. *p < 0.05; **p < 0.01; ***p < 0.001. n = 10 fields. Three independent experiments were performed.