Colocalization of HA-FGFR1 with different intracellular markers in FGF and NCAM-stimulated cells. (A–C) HA-FGFR1–transfected HeLa cells were incubated with anti-HA antibody (green) and stimulated with FGF-2, FGL, or NCAM-Fc for 10 (A), 30 (C), or 60 min (B). In C, TRITC-Tf (red) was added together with the stimuli. After acid wash, cells were stained with anti-EEA1 (A) or anti–LAMP-2 (B) antibodies (red) as indicated. (D) HeLa cells cotransfected with HA-FGFR1 (red) and Rab11-GFP (green) were incubated with anti-HA antibody and stimulated with FGF-2, FGL, or NCAM-Fc for 60 min. After acid wash, cells were stained with Cy3-conjugated anti–mouse antibody. Yellow staining indicates the colocalization of HA-FGFR1 with endosomal markers. Bar, 10 µm.