Axonal Regeneration in Nematodes

Science Signaling  10 Feb 2009:
Vol. 2, Issue 57, pp. ec54
DOI: 10.1126/scisignal.257ec54

During nervous system development, a huge number of axons reach out toward their connections. In the adult, however, such outgrowth is much less common. When an adult nerve is injured, neurons are sometimes able to grow out new axons, but in humans, this imperfect process occurs more readily for nerves of the peripheral nervous system. Hammarlund et al. now shed some light on the molecular tools that support axon regeneration in the nematode, Caenorhabditis elegans, and differentiate the process from normal development. In worms in which a genetic fault leads to excessively brittle axons, or in which a laser is used to cut axons, regeneration of the axon from the remaining stump depended upon a key kinase pathway. This kinase functions early in the road to regeneration but does not seem to be involved during initial development of the axons.

M. Hammarlund, P. Nix, L. Hauth, E. M. Jorgensen, M. Bastiani, Axon regeneration requires a conserved MAP kinase pathway. Science 323, 802–806 (2009). [Abstract] [Full Text]