Pancreatic cells are arrested in their differentiation process in neurod1 morphants and the expression of sox4b is not maintained. Ventral views with the anterior to the left of the pancreas of embryos analyzed by visible (C-H, U-X) or fluorescent (A-B, I-T) WISH. (A-H) Pancreatic expression of mnx1, arx, isl1 and pax6b in controls and Mo2-neurod1 morphants at 24 hpf, the number of isl1+ cells in control morphant (50.4 ± 2.1) was reduced about 2.1 fold in the Mo2-neurod1 morphant (24.1 ± 1.2) and the number of pax6b+ cells in control morphant (40.7 ± 1.2) was reduced about 1.8 fold in the Mo2-neurod1 morphant (22.1 ± 1.2). (I-L) Double fluorescent WISH performed with pax6b(I, J) or isl1(K,L) probe together with a mix of insulin (ins) and somatostatin (sst) probes on 24 hpf controls or Mo2-neurod1 morphants. Z-plane confocal images (M-T) Double fluorescent WISH performed with sox4b and neurod1 on 14 hpf and 18 hpf controls or Mo2-neurod1 morphants. Confocal projection images (U-X) WISH performed with sox4b and neurod1 on 24 hpf controls or Mo2-neurod1 morphants. Scale bars : 50 µm hpf, hours post fertilization; WISH, whole-mount in situ hybridization.