Cftr plays an important role in the pancreas. A–F: Five dpf cftr−/− pancreata have fewer CACs (anti-Nkx6.1, green) (A–C), and secondary islet cells induced by DAPT treatment (anti-insulin plus anti-glucagon plus anti-somatostatin, arrows, red) (D–F) compared with cftr+/− and wild-type pancreata. Scale bar = 100 μm. G–I: Quantification of the number (#) of CACs (G), surface area (H), and number of induced secondary islet cells (I) in wild-type, cftr+/−, and cftr−/− 5 dpf pancreata. N, number of pancreata quantified. **P < 0.05. ***P < 0.001, t test.