Fig. 6

(a–c) Eye fluorescence assay: peak fluorescence intensity in the retinal vascular bed of ctns^−/− zebrafish larvae and wild-type larvae (N = 20 each). Fluorescence intensities were evaluated using fixed diameter circles by the ImageJ software. (a) A representative wild-type 4 dpf larva (24 h post-injection) (bar = 200 μm). (b) A representative ctns^−/− 4 pdf larva (24 h post-injection) (bar = 200 μm). (c) Quantitation of peak fluorescence intensities in the retinal vascular bed of both genotypes. (d–i) Histopathological functional evaluation: (d) A representative proximal tubule of wt larva injected with the 70-kDa labelled dextran (bar = 10 μm). (e) A representative proximal tubule of wt larva injected with the 4-kDa labelled dextran (bar = 10 μm). (f) A representative proximal tubule of ctns^−/− larva injected with the 70-kDa labelled dextran (bar = 10 μm). (g) A representative proximal tubule of ctns^−/− larva injected with the 4-kDa labelled dextran (bar = 10 μm). (h) A higher magnification of the proximal tubules of both genotypes showing internalized 70-kDa dextran within cytosolic puncta that likely correspond to endocytic compartments (marked areas in panels d and f) (bars = 5 μm). (i) Quantitation of the number of dextran puncta in both high and low molecular weight dextran injections in both genotypes (N = 10 for each genotype and each condition). *P < 0.05, ***P < 0.001.