Apoptosis in Spca11D mutants. (A,B) MicroCT scans of E8.75 wild-type and Spca11D embryos (dorsal views). White arrowhead indicates midbrain area, unfilled arrowhead hindbrain area. (C-H) Immunodetection of activated caspase 3 (αCasp3) in wild-type and Spca11D embryos at E8.75 (C,D), E9.5 (E,F) and E10.5 (G,H). (I) Plot represents average apoptotic index (activated caspase 3 foci/total number of nuclei) in wild-type and Spca11D embryos at E8.75, E9.5 and E10.5 (n=10 sections from three biological replicates for each stage and genotype). HM, head mesenchyme; NT, neural tube. Error bars indicate s.e.m. Scale bars: 300 µm (A,B); 100 µm (C-H).