Expression of Wnts in the developing murine secondary palate.

Morphogenesis of the mammalian secondary palate requires coordination of cell migration, proliferation, differentiation, apoptosis and synthesis of extracellular matrix molecules by numerous signal transduction pathways. Recent evidence suggests a role for members of the Wnt family of secreted cytokines in orofacial development. However, no study has systematically or comprehensively examined the expression of Wnts in embryonic orofacial tissue. We thus conducted a survey of the expression of all known Wnt genes in the developing murine secondary palate. Using an RT-PCR strategy to assay gene expression, 12 of the 19 known members of the Wnt family were found to be expressed in embryonic palatal tissue during key phases of its development. The expression of 5 Wnt family members was found to be temporally regulated. Moreover, these Wnts had unique spatio-temporal patterns of expression which suggested possible roles in palatal ontogeny.