Shh signaling is essential for rugae morphogenesis in mice
입천장주름 발생에 있어 Shh의 역할
Dept. of Dentistry/박사
Secondary palate development in mammals is a critical process that depends on complex cellular and molecular events. Corrugated structures of palatal ridges, or rugae palatinae, are observed on the hard palate region in most mammalian species, but their number and arrangement are species specific. Nine palatal ridges are found on the mouse secondary palate. Reciprocal signaling of epithelial–mesenchymal interactions plays a pivotal role in the growth of the secondary palate. Epithelial Shh (sonic hedgehog) signaling is closely related to both the mesenchymal Fgf (fibroblast growth factor) and Bmp (bone morphogenetic protein) pathways. Mice possess secreted Hh (hedgehog) ligands that bind to the membrane-bound receptors Ptch1 and Ptch2. Gli1 and Glil2 are transcriptional activators of Hh signaling. Wnt family members including LEF1 (lymphoid enhancer factor 1) may play a functional role in orofacial morphogenesis. Maternal transfer of 5E1 (an anti-Shh antibody) to mouse embryos through the placenta, and mathematical analysis were used to demonstrate that Sostdc1, a secreted inhibitor of the Wnt pathway, is a downstream target of Shh. We suggest that interactions between Wnt, Shh, and Sostdc1 underlie a pivotal mechanism controlling the spatial patterning of palatal ridges.