Fig. 1. Expression of ephrin-B proteins in chick embryos during early (A-C) and late (D-F) stages of neural crest cell migration. Whole-mount staining of stage-14 (A) and stage-23 (D) embryos with EphB2-Fc, visualized with anti-human Fc antibody coupled to alkaline phosphatase. Labelling revealed a similar pattern of expression in both developmental stages. Lateral views of the trunk region (B,E) show strong expression of ephrin-B ligands in the posterior half of the somites. Transverse sections of stage-14 and stage-23 embryos at midtrunk level show distribution of ephrin-B protein in the posterior sclerotome (C) (sc) and in the dorsolateral pathway (C,F) (arrows).