Joint interpretation of AER/FGF and ZPA/SHH over time and space underlies hairy2 expression in the chick limb.

ABSTRACT: Embryo development requires precise orchestration of cell proliferation and differentiation in both time and space. A molecular clock operating through gene expression oscillations was first described in the presomitic mesoderm (PSM) underlying periodic somite formation. Cycles of HES gene expression have been further identified in other progenitor cells, including the chick distal limb mesenchyme, embryonic neural progenitors and both mesenchymal and embryonic stem cells. In the limb, hairy2 is expressed in the distal mesenchyme, adjacent to the FGF source (AER) and along the ZPA-derived SHH gradient, the two major regulators of limb development. Here we report that hairy2 expression depends on joint AER/FGF and ZPA/SHH signaling. FGF plays an instructive role on hairy2, mediated by Erk a

SUBMITTER: Sheeba CJ 

PROVIDER: S-EPMC3507187 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature