Fig. 4

Fig. 4 Both cones and rods are gradually deformed at the early stage but only cones are selectively eliminated in the els mutant. (A, B) Plastic sections of wild-type (A) and els mutant (B) retinas at 3 wpf. The ONL is thin in the els mutant retinas. (C, D) Labeling of wild-type (C) and els mutant (D) retinas with zpr-3 (red), which stains the rod OS. All the nuclei were labeled with Sytox-green (green). The rod OS is irregularly patterned in the els mutant (D). (E, F) Labeling of wild-type (E) and els mutant (F) retinas with zpr-1 (red), which stains double-cone photoreceptors (red cones/green cones). All the nuclei were labeled with Sytox-green (green). The zpr-1-positive cones are irregularly patterned and decrease in number in the els mutant (F). (G, H) OKR of 3 wpf wild-type (G) and els mutant (H) larvae under photopic condition where cone photoreceptors mainly function. Eye positions were defined by angles between the body axis and the major axis of the ellipse to which the eye shape approximates. Eye positions were plotted over time during optokinetic stimulation in one direction. The wild-type larvae showed a typical normal OKR, but there was no OKR in the els mutant, suggesting that the els mutant lacks the cone-mediated phototransduction. (I, J) OKR of 3 wpf wild-type (I) and els mutant (J) larvae under scotopic condition where rod photoreceptors mainly function. In the els mutant, a regular pattern of eye pursuit to moving stimuli and saccade was observed, suggesting that the els mutant has the rod-mediated scotopic vision. (K, L) Plastic sections of central retina of wild-type (K) and els mutant (L) larvae at 6 mpf. The morphology of the photoreceptor cell layer is abnormal in the els mutant. The layer of rod nuclei (n) becomes thick, typical cone cell morphology (c) is missing, and pigmented epithelium (p) invaginates more deeply into photoreceptor cell layer. (M, O) Labeling of central retina of wild-type (M) and els mutant (O) larvae at 6 mpf with anti-rhodopsin antibody (red). All the nuclei are counterstained with Sytox-green (green). Almost all the photoreceptors retained in the els mutant are labeled with anti-rhodopsin antibody, suggesting that most ONL cells are rods. (P, Q) Labeling of central retina of wild-type (P) and els mutant (Q) larvae at 6 mpf with zpr-1 antibody (red). All the nuclei are counterstained with Sytox-green (green). There are almost no zpr-1-positive cells in the ONL of the els mutant, suggesting that red cones and green cones are eliminated in the els adult retina. (R, S) Labeling of central retina of wild-type (R) and els mutant (S) larvae at 6 mpf with anti-blue opsin antibody (red). All the nuclei are counterstained with Sytox-green (green). There are almost no blue opsin-positive cells in the ONL of the els mutant, suggesting that blue cones are eliminated in the els adult retina. (T, U) Labeling of central retina of wild-type (T) and els mutant (U) larvae at 6 mpf with anti-UV opsin antibody (red). All the nuclei are counterstained with Sytox-green (green). There are almost no UV-opsin-positive cells in the ONL of the els mutant, suggesting that UV cones are eliminated in the els adult retina.