Figure 4.

A, B, Typical examples of single synaptic ribbon complexes (top views) of rod photoreceptor synapses double-immunolabeled with rabbit polyclonal antibodies against RIBEYE (A, B) and mouse monoclonal antibodies against dynamin (A, B) in Tulp1 knock-out mice (B) and littermate control mice (A). C, D, Single synaptic ribbon complexes (top views) of rod photoreceptor synapses double-immunolabeled with rabbit polyclonal antibodies against RIBEYE (C, D) and mouse monoclonal antibodies against clathrin heavy chain (C, D) in Tulp1 knock-out mice (D) and littermate control mice (C). Both dynamin and clathrin heavy chain are highly enriched in the periactive zone of control mice, as previously described (Wahl et al., 2013; Dembla et al., 2014). In contrast to littermate control mice, both dynamin and clathrin heavy chain were nearly completely absent from the periactive zone of Tulp1 knock-out mice (B). The fluorescent dyes coupled to the secondary antibodies were switched on purpose in C, D versus A, B to demonstrate that the kind of fluorophore conjugated to the secondary antibody has no influence on the immunolabeling result. All images were obtained by SR-SIM. Representative results obtained from four animals (each genotype) of four litters (three experiments from each wild-type and knock-out animal). OPL, Outer plexiform layer. Scale bars, 1 μm.