Fig. 2

Rod outer segments were not developed in rpgrip1 ^−/− zebrafish. (A) Photoreceptor outer segments and inner segments were shorter in the retinas of rpgrip1 ^−/− zebrafish at 5 and 7dpf shown by haematoxylin & eosin staining. Double-headed yellow arrow shows the outer/inner segments; the measurement of outer segment length was shown in Supplementary Materials Fig. S3. Inserts show a 3.5 × magnification of the selected regions. (B) Ultrastructural analysis using transmission electron microscopy revealed both rod and cone outer segments were formed in the retinas of 5dpf wildtype siblings but only cone outer segments were presented in the mutants; rod outer segments were not observed in the retinas of 5 examined RPGRIP1 ^−/− mutants at 5dpf. (C) Immunostaining with anti-rhodopsin antibody (4D2) further confirmed rod outer segments were not formed in the retinas of rpgrip1 ^−/− mutants at 5dpf; rhodopsin was mislocalized in whole rod cell body. Nuclei were shown in blue using DAPI. COS, cone outer segments; GCL, ganglion cell layer; INL, inner nuclear layer; M, mitochondria; MEL, melanosome; ONL, outer nuclear layer; RPE, retinal pigment epithelium; ROS, rod outer segments.