Dougherty, M., Kamel, G., Grimaldi, M., Gfrerer, L., Shubinets, V., Ethier, R., Hickey, G., Cornell, R.A., and Liao, E.C. (2013) Distinct requirements for wnt9a and irf6 in extension and integration mechanisms during zebrafish palate morphogenesis. Development (Cambridge, England). 140(1):76-81.
Development of the palate in vertebrates involves cranial neural crest migration, convergence of facial prominences and extension
of the cartilaginous framework. Dysregulation of palatogenesis results in orofacial clefts, which represent the most common
structural birth defects. Detailed analysis of zebrafish palatogenesis revealed distinct mechanisms of palatal morphogenesis:
extension, proliferation and integration. We show that wnt9a is required for palatal extension, wherein the chondrocytes form a proliferative front, undergo morphological change and
intercalate to form the ethmoid plate. Meanwhile, irf6 is required specifically for integration of facial prominences along a V-shaped seam. This work presents a mechanistic analysis
of palate morphogenesis in a clinically relevant context.