Fig. 7. Tissue distribution of phospho-CREB in stage 7 embryos. (A) A whole-mount preparation of anti-phospho-CREB stained embryo. Although anti-phospho-CREB immunoreactivity is broadly observed, stronger and weaker staining can be seen in the neural folds and midline tissue, respectively. The inset indicates a magnified view of boxed area and the neural fold is indicated by arrowheads. (B) Anti-phospho-CREB staining on section. Higher levels of CREB phosphorylation are observed in the prospective neural crest cells in the neural fold (arrow). DAPI staining shows cell nuclei.