Fig. 8. Regulatory interactions between Xnot, gsc and frzb during notochord formation. Embryos at the indicated stages (left) were injected with the indicated combination of factors (lower right corner of each panel) and processed for in situ hybridisation with the indicated probes (upper right corner of each panel). (A-H) Vegetal views. (I-L) Dorsal or dorso-lateral views. (M-T) Embryos were bisected along the dorsoventral axis before being processed for whole-mount in situ hybridisation. Injected cells are revealed by their ß-galactosidase activity (red). Gene expression is shown in purple.