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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, RESULTS. Meshes: Animals, Cell Movement, Craniofacial Abnormalities, Gene Knockdown Techniques, Glucuronosyltransferase, Glycosyltransferases, Hyaluronan Synthases, Hyaluronic Acid, Membrane Proteins, Neural Crest, Xenopus Proteins, Xenopus laevis.
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Is hyaluronan required for cranial neural crest cells migration and craniofacial development? Context: Hyaluronan is a crucial glycosaminoglycan of the vertebrate embryonic extracellular matrix able to influence cell behaviour, both by assembling the pericellular matrices and by activating signal transducing receptors such as CD44. We showed that the hyaluronan synthases, Has1 and Has2, and CD44 display a dynamic expression pattern during cranial neural crest cells (NCC) development. By knocking down Has1 and Has2 gene functions, we revealed that hyaluronan synthesized by Has1 and Has2 is necessary for the proper development of the visceral skeleton.
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The data suggest that hyaluronan helps to maintain the active migratory behaviour of cranial NCC, and that its presence around pre-chondrogenic NCC is crucial for their survival. CD44 knock down also suggests that the role of hyaluronan in cranial NCC migration could be mediated, at least in part, by the activation of CD44. These findings contribute to the unveiling of the functional relation between NCC and their extracellular environment during craniofacial development. Final Decision: yes