Fig. 3.

Loss of Tcf4 causes increased proliferation in the intestinal epithelium of Tcf4^Null E13.5 embryos. (A) Membrane bound GFP marks Tcf4 lineage and reveals increased proportion of Tcf4 lineage in the epithelium of Tcf4^Null E13.5 embryos. Yellow arrows mark red cells that have never expressed Cre and blue dotted line marks the endoderm/epithelium (B). Phh3 staining (blue) reveals increased numbers of mitotic cells in Tcf4^Null E13.5 embryos. (C) BrdU staining (red) reveals increased numbers of cells in S phase of the cell cycle in Tcf4^Null E13.5 embryos. Unequal variance two-tailed t test. Horizontal line, mean (scale bar, 50 μm).