Figure 5. Localization study of phototransduction and IFT proteins in Lca5^gt/gt retinas.

(A) OS proteins rhodopsin (RHO) and cone opsin were mislocalized to ISs and ONL in Lca5^gt/gt animals, while normally restricted to OSs in controls. All sections were obtained at P14. (B) Localization of transducin and arrestin in dark-adapted and light-stimulated animals (P14). In dark-adapted wild-type animals, transducin localized to OSs and arrestin to ISs, ONL, and outer plexiform layer (OPL). After light stimulation, transducin was mainly found in the ISs, with weaker staining in the ONL and outer plexiform layer, whereas arrestin translocated to the OSs. In Lca5^gt/gt dark-adapted animals, the majority of transducin was found in the OSs, with weaker staining in other layers. Arrestin localization in Lca5^gt/gt dark-adapted animals was similar to that in dark-adapted wild-type mice. In light-stimulated Lca5^gt/gt mice, transducin not only was found in the ISs, but also showed diffuse staining in the entire ONL. Arrestin staining appeared diffusely throughout the photoreceptor layer, with less pronounced OS staining than in wild-type mice. (C) Localization of Ift20, Ift88, or Ift140 in connecting cilia of photoreceptors was not affected by inactivation of Lca5 compared with wild-type at P9. GT335 specifically stained connecting cilia. Scale bars: 50 μm (A and B); 10 μm (C). Enlarged views are shown in the insets (C, ×3).