A network model of developmental gene hierarchy.

A network model of development governing the whole temporal and spatial hierarchy of early embryogenesis and pattern formation in Drosophila is introduced. The network is related to a neural network model, with its units being developmental genes mostly connected by the genes' DNA-binding products. The developmental network's agreement with predictions regarding architecture and function of the neural network provides adequate grounds for an analogy between the two. The model is tested through computer simulations--predictions compare favorably with experimental observations. The model not only incorporates a program of control at gene level, but also makes a direct connection with current molecular studies throughout the whole hierarchy of the early embryogenesis of Drosophila.