The determination of the neuronal phenotype

This chapter addresses the following questions: What are the key regulatory genes that specify a neuronal fate and a particular neuronal identity? What do they do? How are they controlled? In addition of identifying key regulatory genes, an attempt is also made to address the "logic" of neuronal determination and differentiation. It argues that current knowledge of the details of the underlying molecular genetic circuitry that determines the identity of any kind of neuron, in any organism, remains sketchy. However, a few general principles are beginning to emerge, particularly the idea that neuronal identity is implemented in series and in parallel in a collection of subprograms, rather than one coordinately active "master" program.