Phenotypic characterization of panx1a−/− larvae – (a) Age-matched wild type TL and panx1a−/− larvae (6 dpf) showing regular morphology. (b) RT-qPCR analysis of pannexin expression in 6 dpf larva. (c) The panx1a expression is reduced in the adult panx1a−/− zebrafish. The expression was determined using an affinity purified rabbit anti-panx1a antibody directed against the carboxy-terminal 129 amino acids of the Panx1a protein. Detection of the PSD-95 protein in cone terminals served as an internal control. Cell nuclei were stained with DAPI. In wild type TL fish arrows indicate Panx1a immunoreactivity found in the horizontal cell layer as reported previously19,20. The immunoreactivity was significantly reduced in panx1a−/− fish. Residual staining was overlapping with DAPI stained nuclei and considered as unspecific. Abbreviations: PL, photoreceptor layer; ONL, outer nuclear layer; OPL, outer plexiform layer; INL, inner nuclear layer; IPL, inner plexiform layer; GCL, ganglion cell layer. Scale bar 100 µm. n.d., Not detected. Significance: ***p-value < 0.001.