Palatal fusion at a Snail's pace Available to Purchase

The role of Snail proteins in patterning vertebrate embryos is varied and widely documented. They regulate epithelial-mesenchymal transitions by downregulating epithelial-specific genes and are involved in other cellular processes, such as neural crest delamination. Thomas Gridley's group now report that, surprisingly, Snai1 and Snai2, encoding Snail and Slug, respectively, have no apparent role in neural crest generation or delamination in mice, but are crucial for proper craniofacial morphogenesis(p. 1789). They show that the deletion of both copies of Snai1 in embryonic neural crest cells performed on a null Snai2 genetic background results in multiple craniofacial defects, and a cleft palate defect that is very different from that seen in Snai1^+/- Snai2^-/-mouse embryos. This cleft palate defect arises from the failure of Meckel's cartilage to extend the mandible, a condition also seen in humans with Pierre Robin Sequence, in which a smaller mandible prevents the...