Genetic interaction between Wnt/β-catenin and BMP receptor signaling during formation of the AER and the dorsal–ventral axis in the limb

Abstract

By conditional gene ablation in mice, we found that β-catenin, an essential downstream effector of canonical Wnt signaling, is a key regulator of formation of the apical ectodermal ridge (AER) and of the dorsal–ventral axis of the limbs. By generation of compound mutants, we also show that β-catenin acts downstream of the BMP receptor IA in AER induction, but upstream or parallel in dorsal–ventral patterning. Thus, AER formation and dorsal–ventral patterningof limbs are tightly controlled by an intricate interplay between Wnt/β-catenin and BMP receptor signaling.