Figure 6
No chondrogenic and osteogenic differentiation in the developing humerus due to lack of functional Apc. (A-B) Immunostaining for β-catenin combined with Alcian blue (AB) staining (A), combined von Kossa-Toluidine blue staining (B), and (C-J) gene expression analysis by in situ hybridization with indicated probes for (C-F) chondrocytes, (G-I) osteoblasts and (J) osteoclasts on consecutive transversal sections of the developing humerus of a Col2a1-Cre;Apc15lox/15lox embryo and control littermate at E16.5. β-Catenin-positive spindle-shaped cells organized in clusters and failed to express chondrogenic and osteogenic markers (arrowheads). β-Catenin-negative cells at the periphery of these clusters expressed early chondrogenic markers only (arrows), probably due to lack of Cre-mediated loss of functional Apc. Scale bars: 100 μm.