Fig. 6. Effect of simultaneous silencing of Rab3A and Rab27A on the number of vesicles docked to the plasma membrane in PC12 cells. (A) Confocal images of a PC12 cell showing colocalization of endogenous Rab3A (green signals in the left panel) and Rab27A (red signals in the middle panel). The right panel shows the overlay between Rab3A and Rab27A (yellow signals in the right panel). Scale bar=10 µm. (B) Typical TIRF images of plasma membrane-docked vesicles in a control cell (left) and a Rab3A- and Rab27A-siRNA-expressing cell (right). The bottom panels are magnified images of the boxed area. Scale bar=5 µm. (C) The density of docked vesicles was determined by counting the vesicles in each image (n=6 cells in each). (D) The number of NPY spot disappearance events in 5 minutes was counted as fusion events (n=6 cells in each). Data shown are mean values ± s.e.m. and were analyzed by one-way ANOVA followed by Newman-Keuls multiple comparison test. ^*P<0.05, ^**P<0.01, and ^***P<0.001, respectively, in comparison with the control. Note that simultaneous silencing of Rab3A and Rab27A caused a significant reduction of vesicle density than silencing of Rab3A or Rab27A alone.