Fig. 8. Ablation of Rarb and Rarg in neural crest cells impairs apoptosis and gene expression in the periocular mesenchyme. (A-D) Distribution of apoptotic cells (assessed by TUNEL assays) in E11.5 wild-type (A,B) and Rarb/g^{NCC–/– lacZ} (C,D) fetuses. (E-H) In situ hybridizations with digoxigenin-labeled Eya2 (E,G) and Foxc1 (G,H) antisense riboprobes on frontal sections through the eye of E11.5 wild-type (E,F) and Rarb/g^{NCC–/– lacZ} (G,H) fetuses. The histological sections illustrated have been selected to provide the best match between mutant and wild-type embryos. (A-D) Sections are counterstained with methyl green. Red brackets indicate the periocular mesenchyme. d, dorsal retina; le, lens; o, optic nerve; rpe, retinal pigment epithelium; v, ventral retina. Scale bar: 50 µm.