ER dynamics before TSA treatment. COS-7 cells were transfected with GFP–Sec61- β (green) and imaged by time-lapse confocal microscopy for 5 min before 125 nM TSA treatment. Shown is the same 10 × 10–µm region in the cell periphery as shown in Video 5. Frames were taken every 5 s, and the video is shown at 6 frames/s.