Figure 1

Spatiotemporal expression of Sel1l during development of the mouse pancreas. Pancreatic sections from timed Sel1l^+/βgeoembryos were co-immunostained with antibodies against βGal (red) and various pancreatic markers (green) as indicated on the left side of each panel. (B and H) Magnified views of the boxed area in A and G, respectively. (A-D) βGal expression at E12.5. βGal expression begins in a small number of cells within the core pancreatic epithelium at E12.5 (A). At this stage, there is no co-expression of βGal and SOX9 (B); however, βGal is co-expressed with either glucagon (C) or insulin (D). (E-F) βGal expression at E14.5. βGal is differentially expressed in the PDX1⁺ cells (E). While high βGal signal was detected in the epithelial branches (arrows), no or very low Gal signal was detected in the core "duct-like" epithelium (arrowhead). These core epithelial cells correspond to the subset of PDX⁺ cells that express SOX9 (F). (G-J) βGal expression at E15.5. βGal expression increases markedly in the core pancreatic epithelium (G and H, asterisks). βGal co-localizes with either glucagon (I, arrows) or insulin (J, arrows). (K-L) βGal expression at postnatal day 1. βGal is expressed in both islet and acinar tissues (K, asterisk and arrow, respectively). βGal co-localizes with PDX1 in the islet tissue (L). Scale bars: (A, G, I and J) 50 μm; (B-F, K-L) 100 μm.