The vertebrate neural tube gives rise not only to the central and peripheral nervous systems, but also to a diverse range of non-neural cells and tissues, including melanocytes, bone and cartilage, and connective tissue. These are all derived from the neural crest, a migratory cell population that originates in the dorsal neural tube. In this issue, we highlight two aspects of neural crest development.
On page 763, Gamill and Bronner-Fraser consider the earliest stage of neural crest development, when cells undergo an epithelial–mesenchymal transition and delaminate from the dorsal neural tube. Researchers are trying to define the molecular basis of neural crest induction, but progress has been hampered by the limitations of the available animal models. Grafting experiments in chick and frog embryos have contributed greatly to our understanding of neural crest induction at the cellular level, but these organisms are not particularly amenable to genetic approaches. Conversely, the mouse is excellent for genetic studies, but the inaccessibility of the embryos makes it unsuitable for classic embryology. As the authors discuss, recent advances in genomic technology provide new opportunities to combine embryological and genetic approaches in the same organism
