Development of the Pancreas, Biliary System and Intestine
Our research into the origin and development of the endoderm includes three main areas of study:
- The molecular mechanisms that establish organ domains along the anterior-posterior axis. One fundamentally important question is: How are some endoderm cells directed to form the pancreas whereas other cells are directed to form the liver? Our mouse-chick experiment suggests that endoderm patterning is highly conserved between birds and mammals.
- Molecular pathways that establish the foregut, midgut and hindgut domains. We have used both in vitro and in vivo analyses to identify that FGF4-mediated signaling plays a role in establishing gut tube domains in two ways. Establishing gene expression domains during gut tube patterning is critical for subsequent stages of endoderm organogenesis.
- Pancreas and biliary development. We have shown that the extra hepatobiliary system shares a common origin with the ventral pancreas and not the liver, as previously thought. Our studies also suggest that components of the Wnt pathway are expressed during pancreas development and that beta-catenin / Wnt signaling is required for expansion and maintenance of exocrine progenitor cells during development.