Eyes of cdh4 morphants are small and lack discrete laminae at 2 days postfertilization (dpf). A-K: Zebrafish embryos were injected with either standard control morpholino oligonucleotide (MO, A,E,H) or cdh4 MO (B-D,F,G,I-K). A-D: At 2 days postfertilization (dpf), living embryos were imaged using differential interference contrast microscopy. Ventral views of eyes are shown (A-D). A: Rostral is up and lateral is left. In eyes of control embryos, all the major layers characteristic of the adult retina, the retinal ganglion cell layer (rgl), inner plexiform layer (ipl), the inner nuclear layer (inl), outer plexiform layer (opl) and the outer nuclear layer (onl) are visible. B-D: In cdh4 MO-injected embryos, a graded series of effects on eye development were seen. B,C: In moderately affected embryos, eyes were smaller in size, the inner plexiform layer was sparse, the distance between the inner plexiform layer and the lens was not uniform, and the outer nuclear layer was sparse or absent. D: Both the eyes and lens of severely affected embryos were small and laminae were altogether absent. E-G: BODIPY-ceramide labeled living 2 dpf embryos were imaged using confocal microscopy. E: In control embryos at 2 dpf, there was a distinct continuous inner plexiform layer separating the retinal ganglion cell layer and the inner nuclear layer. F: In moderately affected 2 dpf cdh4 MO knockdowns, the inner plexiform layer was sparse and irregular and the outer nuclear layer was absent. G: In severely affected 2 dpf cdh4 MO knockdowns, lamination was absent. H-K: Toluidine blue-stained plastic sections of 2 dpf embryos clearly show the laminar organization of cells within the control retina (H). I: In slightly affected cdh4 knockdowns, laminae are present, but cell shape, particularly within the outer nuclear layer differs from that of controls. J,K: In severe cdh4 knockdowns, laminae are absent. Scale bars = 50μm.
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