Prospects & Overviews
Signalling mechanisms regulating axonal branching in vivo
Article first published online: 8 SEP 2010
Copyright © 2010 WILEY Periodicals, Inc.
Volume 32, Issue 11, pages 977–985, November 2010
How to Cite
Schmidt, H. and Rathjen, F. G. (2010), Signalling mechanisms regulating axonal branching in vivo. Bioessays, 32: 977–985. doi: 10.1002/bies.201000054
- Issue published online: 14 OCT 2010
- Article first published online: 8 SEP 2010
- DFG. Grant Number: SFB665
- axonal branching;
- axonal pathfinding;
- brain-derived neurotrophic factor;
- cyclic guanosine monophosphate signalling;
- retinotectal system
Identification of the molecular mechanisms underlying axonal branching in vivo has begun in several neuronal systems, notably the projections formed by dorsal root ganglion (DRG) neurons or retinal ganglion cells (RGC). cGMP signalling is essential for sensory axon bifurcation at the spinal cord, whereas brain-derived neurotrophic factor (BDNF) and ephrinA signalling establish position-dependent branching of RGC axons. In the latter system, the degradation of specific signalling components, via the ubiquitin-proteasome system, may provide an additional mechanism involved in axon branching of RGC. The process of arborisation is essential for neurons to innervate multiple targets and to build topographic maps. The various forms of branching found in different types of neurons are regulated by distinct signalling pathways activated by multiple extracellular cues in addition to axonal guidance factors. These signalling cascades, together with transcriptional programs, most likely interact and trigger the polymerisation or depolymerisation of the actin and tubulin cytoskeleton to regulate branching.