Relationship of PRA1-LIR to Golgi and cilia markers. (A-C) Immunofluorescent double labeling of PRA1-LIR and the cis-Golgi marker, GM-130-LIR, was performed on P10 mouse retinas. In control experiments (A), blood vessels stained non-specifically (arrowheads). In wt retinas (B), intense GM-130-LIR (magenta) co-localized with PRA1-LIR (green) in the proximal IS. Both overlapping and distinct punctae appeared within the streak-like pattern in the ONL (inset). Diffuse single staining of PRA1-LIR was seen in the distal IS. In rd1 retinas (C), GM-130-LIR was distributed more extensively in the IS (inset) with single (magenta arrowhead) and double (white arrowhead) labeled punctae in the distal IS. Images are single confocal slices. Insets illustrate the IS region, indicated between the white bars, at 4× higher magnification. (D-F) Immunofluorescent double labeling of Rab6-LIR (green) and GM-130-LIR (magenta) was performed on P10 wt (D, E) and rd1 (F) mouse retinas. Non-specific staining of blood vessels was present but not seen in the IS region illustrated (D). Rab6-LIR was closely apposed to GM-130-LIR with minimal overlap in both wt and rd1. (G, H) Immunofluorescent double labeling of PRA1-LIR (green) and RP1-LIR (magenta) was performed on P21 wt mouse retinas. No staining was detected in control experiments (G). PRA1-LIR punctae were seen throughout the IS region and frequently in close proximity to RP1-LIR (H, arrows), but not colocalizing. Very sparse PRA1 stained punctae were seen beyond RP1-LIR (arrowheads). Magnification for D-H is the same as insets in B and C. Abbreviations are the same as Figure 5.