No simpler than mammals: axon and dendrite regeneration in Drosophila.

Despite important progress made in understanding the mechanisms of axon regeneration, how a neuron responds to an injury and makes a regenerative decision remains unclear. In this issue of Genes & Development, Song and colleagues (pp. 1612-1625) investigate axonal and dendritic regeneration in the Drosophila peripheral nervous system (PNS). With some mechanisms shared with mammals, this study reveals surprisingly complicated regenerative responses in terms of cell type, developmental stage, and mechanism specificity. With forward genetic potential, such invertebrates should be powerful in dissecting the cellular and molecular control of neuronal repair.