Figure 1. Single inactivation of Gata4 and Gata6 does not affect pancreas formation.

(A–D) Immunohistochemical analyses show strong expression of GATA4 in acinar cells (arrowheads in A) and GATA6 in endocrine cells (arrows in C) in pancreatic sections of control mice at P1. Loss of GATA4 (B, arrowheads) and GATA6 (D, arrows) in newborn conditional mutant mice is confirmed by immunohistochemical analysis. (E–G) Gross morphology of neonatal WT and conditional mutant guts. H&E-stained sections of newborn control (H), Gata4 (I), and Gata6 (J) conditional knockout pancreata does not reveal major defects in pancreas architecture. Mature acinar (amylase), ductal (mucin) (K–M), and islet (insulin and glucagon) markers (N–P) are normally expressed in single Gata4 and Gata6 conditional knockout mice. Insets in H–M show higher magnification of acinar cells. Mild ductal dilation in acinar cells of Gata4^flox/flox;Pdx1-Cre is observed (I and L, insets). Nuclei are counterstained with DAPI in K–P. Scale bars: 50 μm; 25 μm (insets).