Figure 3.

The gross morphology of ribbon synapses is normal in nsfa^I209N/st53 mutants

(A) Image and diagrams of neuromasts depicting the hair cells, afferent neurons, and ribbon synapses.

(B) Representative images of afferent innervation (HNK-1) of hair cells in WT, nsfa^I209N/st53 mutants, and nsfa^st53 mutants. Presynaptic hair-cell ribbons are labeled with Ribeye b antibody (magenta). Note the lack of innervation of nsfa null hair cells.

(C) Ribbon synapses in WT, nsfa^I209N/st53 mutants, and nsfa^st53 mutants. A pan-MAGUK antibody was used to label the postsynaptic density of afferent terminals (green), and ribbons were visualized with anti-Ribeye b antibody (magenta).

(D) Number of ribbons per neuromast (n ≥ 12 neuromasts per genotype).

(E) Average size of each ribbon (n ≥ 12 neuromasts per genotype).

(F) Colocalization of Ribeye b and MAGUK (n ≥ 8 neuromasts per genotype).

(G) Integrated density of MAGUK immunolabel per punctum (n ≥ 12 neuromasts per genotype).

(H) Images of the synaptic vesicle marker VGlut3 in WT, nsfa^I209N/st53 mutants, and nsfa^st53 mutants (Ribeye b in magenta).

(I) Quantification of the intensity of the VGlut3 immunolabel (n ≥ 11 neuromasts per genotype).

Quantification data are shown as mean ± SEM; p values are determined by ANOVA tests to compare with WT group. ns, not significant; *p < 0.05, **p < 0.01, ***p < 0.001. For all experiments, n ≥ 6 fish per genotype (5 dpf). All images and data are representative of 2 or 3 independent experiments. Scale bars, 5 μm.