Focus Issue: Wnt and β-Catenin Signaling in Development and Disease

The Wnt pathways represent key signaling networks involved in development, both in tissue specification and in cellular migration. Wnt signaling also plays key roles in tissue homeostasis in adult animals, and aberrant Wnt signaling is associated with several forms of cancer. This issue includes descriptions of a proapoptotic function for Wnt signaling in melanoma, an interplay between Wnt and bone morphogenetic proteins in tooth organogenesis, and a noncanonical role for Wnt in neuronal guidance.