Abstract:
During primary neurulation, the flat neural plate is transformed into a closed neural tube throughout a series of morphogenetic changes driven by a combination of intrinsic and extrinsic forces. Neuroepithelial cell properties like adhesion, polarity, movements and changes in cell shape act as intrinsic forces that determine morphogenesis of the neural tube. In particular, the formation of dorsolateral bendings in the neuroepithelium (dorsolateral hinge-points, DLHP) are crucial events for the neural tube to close in the cranial region. It has been suggested that the transcription factor Pax3 regulates cellular properties involved in the formation of DLHP, since null mutant embryos show flapping neural folds and failure of the neural tube closure in the cranial region. In this study, we analyze the expression pattern of Pax3 in relation to the formation of DLHP. The possible regulation of the cellular properties involved in the bending process is studied in the Sploth embryos (Pax3 mutants) showing exencephaly. The role of neural crest cells, as a dynamic population that affects the architecture of the neuroepithelium during neurulation in the mouse, was also investigated.