Fig. 12

Annular gap junction vesicle fission. In the time-lapse imaging montage the splitting of an annular gap junction vesicle is demonstrated (a-f). Once the split occurs, the two annular gap junction vesicles (arrow and dashed arrow) move away from one another (d-f). The path and size of annular gap junction vesicles is depicted in the animated 3D reconstruction time-lapse tracking (g, h) and in the corresponding graphs (i, j). Note the yellow line depicting the annular gap junction movement path before (arrowhead) and after the split (arrow) (g) and the corresponding changes in size after fission (i). Inhibiting dynamin function blocks annular gap junction splitting (h, j). Clusters of annular gap junction vesicles, which would be consistent with the splitting/budding process, can be seen with fluorescence light microscopy in (k), and transmission electron microscopy (AGJ, marked with arrowheads in l, m) in the cytoplasm. Note the gap junction plaque (GJ) in the plasma membranes in (m). Membranes have been labeled with DiI (red in k). Bars: 10 μm (a-f), 5 μm (g, h, k), 100 nm (l, m). (a-j from ref. [58], and k-m from ref. [61])