Molecular similarity between the mechanisms of epithelial fusion and fetal wound healing during the closure of the caudal neural tube in mouse embryos.

Abstract

Neural tube (NT) closure is a complex developmental process that takes place in the early stages of embryogenesis and that is a key step in neurulation. In mammals, the process by which the neural plate generates the NT requires organized cell movements and tissue folding, and it terminates with the fusion of the apposed ends of the neural folds. Here we describe how almost identical cellular and molecular machinery is used to fuse the spinal neural folds as that involved in the repair of epithelial injury in the same area of the embryo. For both natural and wound activated closure of caudal neural tissue, hyaluronic acid and platelet-derived growth factor signaling appear to be crucial for the final fusion step. There seems to be no general wound healing machinery for all tissues but rather, a tissue-specific epithelial fusion machinery that embryos activate when necessary after abnormal epithelial opening.