Video 2.
The presence of TfR on IRAP-pHluorin fusing vesicles in a 3T3-L1 fibroblast cell. 3T3-L1 fibroblast cells were transfected with IRAP-pHluorin (green) and TfR-mCherry (red). IRAP-pHluorin vesicle fusions, observed using dual-color TIRF microscope (True MultiColor Laser TIRFM system; Leica) 3 min after insulin stimulation, are categorized into TfR-positive (circles) and -negative (squares) events. The exposure time of IRAP-pHluorin is 30 ms and the exposure time of TfR-mCherry is 50 ms. The video is played at 7 frames per second. Bar, 4 µm.