The Deleted in Colorectal Cancer netrin guidance system: a molecular strategy for neuronal navigation.

1. Neuronal migration is one of the principal events in laying out the architectural plan of the embryonic central nervous system (CNS). In addition, the correct navigation of axonal growth cones to their specific targets is essential for the establishment of the intricate network of axon projections found within the mature CNS. 2. The Deleted in Colorectal Cancer (DCC) guidance receptor, together with its ligands, the netrins, is now emerging as a major navigational system driving both neuronal and axonal migrations. Members of the netrin family of secreted guidance cues are also likely to be ligands for a second DCC-like receptor, neogenin. 3. The present paper reviews the current understanding of DCC-netrin-dependent axon pathfinding within the embryonic spinal cord and suggests novel modes of action for both DCC and neogenin.