Signaling endosomes and growth cone motility in axon regeneration.

During development and regeneration, growth cones guide neurites to their targets by altering their motility in response to extracellular guidance cues. One class of cues critical to nervous system development is the neurotrophins. Neurotrophin binding to their cognate receptors stimulates their endocytosis into signaling endosomes. Current data indicate that the spatiotemporal localization of signaling endosomes can direct diverse processes regulating cell motility, including membrane trafficking, cytoskeletal remodeling, adhesion dynamics, and local translation. Recent experiments manipulating signaling endosome localization in neuronal growth cones support these views and place the neurotrophin signaling endosome in a central role regulating growth cone motility during axon growth and regeneration.