Cell fate choice during early neurogenesis in Drosophila melanogaster.

In the neuroectoderm of the Drosophila embryo, cells have to choose between the neural and epidermal cell fates. The decision in favor of one or the other is under the control of the neurogenic and the proneural genes. Their gene products form a signal relay that ultimately leads to the commitment of each cell to a given fate. Data derived from various experimental approaches suggest that the proteins encoded by the genes Delta and Notch act act at the membrane as signal and receptor, respectively, whereas the genes of the Enhancer of split and the achaete-scute complexes code for transcription factors, which serve to specify the appropriate response by regulating the activities of other genes.