Figure 1.

Induced neurogenin 3 (Ngn3) in the hepatic lineage. (a) Normal ontogeny. Both liver and pancreas develop from the endoderm. The endodermal stem cell divides to form the hepatic and pancreatic stem cells during development. The liver stem cell divides to form biliary cells and hepatocytes. (b) Ngn3-induced ontogeny. Ngn3 induction results in the aborted transdifferentiation of hepatocytes into endocrine cells but successful transdetermination of the liver stem–progenitor cell population. The effects of Ngn3 on the biliary cell population remain to be assessed. PP, pancreatic polypeptide.