Specification of neurons through asymmetric cell divisions.

The brain requires diverse neuronal subtypes to carry out its complex functions. Many types of neurons are produced through asymmetric division, and the molecular mechanisms of asymmetric division have been extensively studied in C. elegans and Drosophila. In these model organisms, the same molecular mechanisms regulate asymmetric divisions throughout development, although diverse cell types are created. How these common mechanisms for asymmetric division can specify diverse neuronal fates, however, is still being discovered. Recent studies suggest that neurons are specified by the combined effects of asymmetric divisions, which are regulated by common mechanisms, and specific transcription factors expressed in the mother cell. 2009 Elsevier Ltd. All rights reserved.