Figure 6.

Expression of AIPL1 in the fetal, child and adult human retina. (A) Immunohistochemical analysis using a rabbit anti-AIPL1 antibody showed that human AIPL1 protein (green fluorescence) was expressed in a subset of the nuclei (red fluorescence) of the human retina at fetal week 14. Expression was only detected in the apical region of the retina, where the newly postmitotic photoreceptors are beginning to differentiate. Some nuclei expressed much higher levels of AIPL1 protein (arrow) than other nuclei (open arrowheads). (B) Approximately 2 weeks later at fetal week 16, the expression of AIPL1 was seen throughout the immature outer nuclear layer (ONL) containing the developing photoreceptors. While all the nuclei in this layer appear to express AIPL1, the level of AIPL1 appeared to be high in some cells and much lower in others as seen at fetal week 14. (C and D) Immunohistochemical analysis shows that the AIPL1 protein (dark brown stain) localizes to the ONL and inner segments (IS) of the photoreceptors within child (age 3) and adult retinas. The adult retinal image was counterstained (blue) to highlight the nuclei of the cells. onbl, outer neuroblastic layer; inbl, inner neuroblastic layer; GCL, ganglion cell layer, OS, outer segments, (A and B) scale bar = 10 μM; (C and D) scale bar = 20 μM.