Fig. 5. Ultrastructure of the DC-OHC and DC-DC junctions. (a) Wide field freeze-fracture view of DC-OHC and DC-DC junctions reveals the overall organization of tight junction strands and the distinct morphologies between the DC-DC and DC-OHC junctions. (b) Anti-ß-actin immunoEM of DC-OHC and DC-DC junctions showing the dense labeling of the cytoplasmic plaque. Importantly, the plane of section passes through the plaque (electron opaque band) revealing it to be a continuous band across the DC phalanges between DC-DC and DC-OHC junctions. Gold particles also label other components of the apical region of the OHC, which correspond to the actin-rich cuticular plate of these cells. Bar, 0.2 µm.