Fig. 1. Expression of Ebf1 and Ebf3 in the chick neural tube. In situ hybridisation was performed as indicated (stages and probes). (A,B) Flat mounts of the hindbrain region showing the generalised expression of Ebf1 and Ebf3, with the exclusion of rhombomeres 3 and 5, coincident with neurogenesis at stage HH14. (C-F) Transverse sections through the spinal cord at stages HH17 and HH20 showing high expression of Ebf1 and Ebf3 in the mantle layer. r, rhombomere.