Fig. 1.

HNF4α is expressed in the gastric epithelium and can be deleted by Cre recombinase from the adult stomach. A: immunohistochemical stain of HNF4α shows it is expressed in the nuclei of isthmal progenitor and pit cells (white arrowhead), neck cells (red arrowhead), and zymogenic chief cells (pink arrowhead), but not in parietal cells (yellow arrowhead) of the mouse gastric corpus. B: immunohistochemical stain of HNF4α in mice 3 wk postinduction of cre recombinase to delete the floxed Hnf4α allele shows its expression is largely lost vs. control staining in A. Note the background positivity of red blood cells in the inset (bracket) but lack of detectable epithelial cell label (images are representative of n = 4 biological replicates). C: HNF4α mRNA levels in control vs. deleted stomachs. Columns represent means ± SD of three biological replicates; ***P < 0.001. Scale bars = 50 μm.