Fig. 6. Relative requirement for ß-catenin in individual endocrine and exocrine cells. Confocal immunofluorescence on E15.5 (A-I') or neonatal (J-L') wild-type versus PBKO pancreata, to detect co-expression of ß-catenin (A,A',D,D',G,G',J,J') with insulin (B,B'), glucagon (E,E'), amylase (H,H') or the duct marker DBA lectin (K,K'). Filled arrowheads indicate examples of cells co-expressing the markers; open arrowheads indicate a lack of co-expression. Note that all insulin⁺ and glucagon⁺ cells are ß-catenin^– in PBKO sections (C',F'), as are the majority of DBA⁺ cells (L'). By contrast, all residual amylase⁺ cells in these pancreata are ß-catenin⁺ (I'), indicating that they derive from cells in which the Catnb gene did not undergo Cre-mediated excision.