FIGURE 1.

Role for Notch signaling in all three intestinal secretory cell lineages. Tamoxifen treatment increased the numbers of ChromograninA-positive EE cells (top row) as well as Paneth cells expressing the cryptdin Crs4c1 (bottom row) in RBP-Jκ^Fl/Fl;Villin-Cre^(ER-T2) mice, compared with wild-type littermates. Insets in the duodenal panels show high-magnification images of the boxed areas, and quantitation of immunohistochemical data is shown (right). The duodenum showed a larger increase in EE cells, whereas Paneth cells were more significantly increased in the ileum. Scale bars = 50 μm.