Fig. 2. EGF induces macropinocytosis of E-cadherin. (A) MCF-7 cells were treated with EGF for 10 minutes, fixed and immunolabeled for endogenous E-cadherin with EEA1 (a) or EGFR-GFP (b). Nuclei were stained with DAPI. Arrows denote localization of E-cadherin (a) and EGFR-GFP (b) to macropinosomes, arrowheads denote membrane ruffles. (B) MCF-7 cells were transiently transfected with YFP-rabankyrin-5, fixed and immunolabeled for endogenous E-cadherin (red) either (a) without or (b) with prior EGF stimulation for 10 minutes, and examined by epifluorescence. Arrows denote overlap of staining between intracellular E-cadherin and YFP-rabankyrin-5. Note formation of numerous macropinosomes upon EGF stimulation of YFP-rabankyrin-5-expressing cells. Second, third and fourth panels are magnifications of boxed areas shown in respective first panels. Bars, 20 µm for all first panels; 2 µm for all other panels.