In humans, neural tube closure defects occur in 1:1000 pregnancies. The design of new strategies for the prevention of such common defects would benefit from an improved understanding of the molecular events underlying neurulation. Neural fold elevation is a key morphological process that acts during neurulation to drive neural tube closure. However, to date, the molecular pathways underpinning...

Mouse embryos homozygous for the loop-tail (Lp) mutation fail to initiate neural tube closure at E8.5, leading to a severe malformation in which the neural tube remains open from midbrain to tail. During initiation of closure, the normal mouse neural plate bends sharply in the midline, at the site of the future floor plate. In contrast, Lp/Lp embryos exhibit a broad region of flat neural plate ...

The vertebrate neural tube develops by two distinct mechanisms. Anteriorly, in the brain and future trunk (cervicothoracic) region, 'primary neurulation' occurs, where an epithelial sheet rolls or bends into a tube. Posteriorly, in the future lumbar and tail region, the neural tube forms by 'secondary neurulation', where a mesenchymal cell population condenses to form a solid rod that undergoes...

Distinct cell types differentiate along the dorsoventral axis of the neural tube. We have cloned and characterized a novel member of the TGF beta gene family, dorsalin-1 (dsl-1), that appears to regulate cell differentiation within the neural tube. dsl-1 is expressed selectively in the dorsal neural tube, and its pattern of expression appears to be restricted by early signals from the notochord...

The neural crest gives rise to numerous derivatives including adrenergic and cholinergic neurons, supportive cells of the nervous system, and melanocytes. In tissue culture, neural crest cells explanted from both cranial and trunk regions were found to differentiate into adrenergic neuroblasts or into pigmented cells when grown in medium containing 10% chick embryo extract. When the embryo extr...

Neural crest cells arise from the ectoderm and are first recognizable as discrete cells in the chicken embryo when they emerge from the neural tube. Despite the classical view that neural crest precursors are a distinct population lying between epidermis and neuroepithelium, our results demonstrate that they are not a segregated population. Cell lineage analyses have demonstrated that individua...

Neural tube defects including spina bifida are common and severe congenital disorders. In mice, mutations in more than 200 genes can result in neural tube defects. We hypothesized that this large gene set might include genes whose homologs contribute to morphogenesis in diverse animals. To test this hypothesis, we screened a set of Caenorhabditis elegans homologs for roles in gastrulation, a to...