Supplementary Figure 1: Lineage tracing using the R26R3 LacZ reporter line and Villin-CreER^T2 mice showed that Villin-CreER^T2 marks intestinal stem cells.

(a) Villin-CreER^T2:R26R double–compound mutant mice were administrated 2 mg of tamoxifen by intraperitoneal injection for 3 d each beginning at 4 weeks of age. On day 60 after tamoxifen injection, X-Gal staining was performed using whole-mount intestinal tissue. (b) More than 95% of the villi in the duodenum, (c) ~90% in the jejunum, (d) ~60% in the ileum and (e) 20–30% in the colon showed LacZ staining. Scale bars, 50 μm. The presence of blue-stained cells 60 d after Cre induction shows that Villin-CreER^T2 is expressed in intestinal stem cells.