Localization of Impdh1 in mouse retina. Frozen fixed retinas were incubated with (A) anti-C-IMPDH1 or (B) anti-C-IMPDH1+2 followed by incubation with Cy3-conjugated goat anti-rabbit secondary antibody (red). Cell nuclei were stained with DAPI (blue). Impdh1 localized to the inner segments and synaptic terminals of photoreceptors (arrows). RPE, retinal pigment epithelium; OS, outer segment; IS, inner segment; ONL, outer nuclear layer; INL, inner nuclear layer.