FIG. 2.

Confocal analysis of K1 internalization. WT and mutant K1-FLAG expression plasmids were transfected into HeLa cells. Forty-eight hours posttransfection, the transfected cells were surface labeled with anti-Flag-Cy3 antibody at 4°C for 1 h and then transferred to 37°C for 20 or 60 min. The cells were fixed and analyzed by confocal microscopy.