Fig. 3. Frodo and Dapper are required for neural development. (A) Localization of Frodo RNA visualized by whole-mount in situ hybridization on a half-embryo at stage 10, sagittal view. (B-M) Morpholinos and RNAs were injected as indicated in Table 3 into a single right animal-dorsal blastomere of 8- to 16-cell stage embryos with (B-H) or without (I-M) nßgal mRNA. Whole-mount in situ hybridization has been carried out with antisense probes for sox2 (B-F), myoD (G,H) and nrp1 (I-M). Suppression of sox2 was observed in cells injected with FrdMO (or DprMO) and nßgal RNA at stage 10.5 (C) or 13 (E,F). (C) The inset is shown on the right at higher magnification. CoMO-injected embryos at stage 10.5 (B), 13 (D) and 20 (I). (G,H) Lack of effect of FrdMO on myoD expression at stage 14. (I-K) Nrp1 expression on the injected side is severely reduced in both anterior and posterior neural tube in FrdMO- and DprMO-injected embryos at stage 20. (L) The nrp1 expression domain becomes narrow posteriorly, but expands anteriorly in the embryos injected with ß-catenin morpholino (ßcatMO). Morphology of an embryo injected with ßcatMO is shown on the right. (M) The effect of FrdMO on nrp1 is restored by Frodo RNA (see also Table 3). (B-H,M) Dorsal view. (I-L) Dorsal view (left), anterior view (right).