What are the molecular mechanisms that specify A-P endoderm pattern at this stage in development?
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. FGF4 represses foregut fate between the gastrula and early somite stages while at the same time promoting midgut and hindgut fate in a graded fashion.
Currently, we are using chick and mouse embryos and human endoderm cultures (from differentiated embryonic stem cells) to identify how FGF signaling directs posterior endoderm patterning in vivo. We have recently begun to investigate how FGF pathways interact with other posterior pathways including the Wnt pathway (in collaboration with Aaron Zorn). Establishing these gene expression domains during gut tube patterning is critical for subsequent stages of endoderm organogenesis.
View publications from the Wells Lab in PubMed.