TRIPARTITE SIGNALING OF PATTERN - INTERACTIONS BETWEEN HEDGEHOGS, BMPS AND WNTS IN THE CONTROL OF VERTEBRATE DEVELOPMENT

A central issue in embryonic development is the resolution of how grou ps of equivalent cells are transformed into orderly and patterned arra ys of distinct cell types. Recent studies suggest the involvement of t he Hedgehog, Wnt and bone morphogenetic protein families in the patter ning of different tissue types in vertebrate embryos. The integrated a ctions of members of these three families of signaling proteins appear to have been recruited in the patterning of neural tissue in addition to several different tissues. Over the past year, a clearer picture o f the diverse roles of these signaling proteins in embryonic developme nt has begun to emerge.