Fig. 7

Notch signaling is required for cell proliferation in the central retina of the rw440 mutant. (A) In situ hybridization of wild-type and rw440 mutant retinal sections with Dl-C RNA probes. (B) In situ hybridization of wild-type and rw440 mutant retinal sections with her4 RNA probes. Both Dl-C and her4 mRNA expressions were localized in the retinal CMZ of wild type (arrowheads, left panels), but expanded towards the central retina in the rw440 mutant (arrowheads, right panels). (C–F) Sections of wild-type (C), rw440 mutant (D), mib mutant (E), and rw440; mib double mutant (F) heads at 3 dpf. (C′–F′) High magnification of retinas shown in panels (C–F). (G–J) The ath5:GFP expression (green) and EdU incorporation (magenta) of wild-type (G), rw440 mutant (H), mib mutant (I), and rw440; mib double mutant (J) retinas at 60 hpf. EdU incorporation is observed in retinal CMZ of wild type (arrowheads, G) and mib mutant (arrowheads, I), but not in the retinal CMZ of rw440 mutant (asterisks, H) and rw440; mib double mutant (asterisks, J). EdU incorporation is observed in the central retina of the rw440 mutant but not in the central retina of the rw440; mib double mutant. (K–N) DAPI labeling (white) and TUNEL (magenta) of wild-type (K), rw440 mutant (L), mib mutant (M), and rw440; mib double mutant (N) retinas. Although very faint dot-like TUNEL signals are observed in mib (M) and rw440; mib (N) mutant retinas, there was no massive cell death in both retinas.