Whole tongue (A, D, G) and single plane confocal images on sections (B, C, E, F, H–K) for EGFP expression to mark NC-derived cells in Wnt1-Cre/ZEG mouse tongue at E12.5, E16.5 and P1. Tongues were sectioned in a sagittal orientation. Epithelial cells are marked with immunoproducts of E-cadherin (E-cad, red). Similar to the R26R reporter, labeled cells are extensively distributed throughout the tongue mesenchyme at E12.5 (A–C). At E16.5 (D–F) and P1 (G–K), EGFP labels are intensely expressed in the mesenchymal cell zone right under lingual epithelium and in the mesenchymal core of taste papillae: see fungiform (white arrowheads), foliate (short arrows) and circumvallate (long arrow) in whole tongue at E16.5 and P1 (G). Scale bars: 500 μm in A, D, G; 100 μm in B, E, H, J, K; 25 μm in C, F, I.