Figure 1.

FGF induces nuclear translocation of FGFR1. (A) MCF-7 cells incubated with FGF-1 for 0–4 h at 37°C were fixed and stained by immunofluorescence by using a polyclonal antibody against endogenous FGFR1. Arrowheads indicate membrane labeling that was only evident on membrane ruffles, whereas arrows denote nuclear FGFR1 labeling. At higher magnification the FGFR1 can be seen inside cell nuclei (inset). (B) MCF-7 cells were incubated with FGF-1 for 24 h at 37°C were fixed and triple labeled using an antibody against endogenous FGFR1, phalloidin to label F-actin in the cell periphery, and DAPI to label cell nuclei. FGFR1 staining overlaps with DAPI-stained nuclei. Bar, 50 μm.