Nerves, Heal Thyselves

In a study published in Neuron, Weizmann scientists have now shown how neurons in the peripheral nervous system “raise the alarm” following injury, sparking a rescue process.

Nerves in the peripheral nervous system (any part of the body aside from the brain and spinal cord) are capable of regenerating, though they often do so poorly or slowly. A better understanding of how they regenerate could advance the treatment of injuries to the peripheral system (such as loss of sensation). It might also provide insights into fixing neurons in the central nervous system.

Nerve cells are uniquely shaped, consisting of a cell body and “arm-like” protrusions that transmit information to the cell (dendrites) and from it (axons). Axons can reach up to one meter in length in humans and are the main conduit for neural communication throughout the body.

Dr. Michael Fainzilber and Ph.D. students Shlomit Hanz and Eran Perlson of the Biological Chemistry Department found that a special protein called importin beta is produced in axons upon injury. This protein binds, among others, to components of a “healing message.” The whole group fastens itself to an “engine” called dynein that chugs along tracks leading from the axon to the nucleus. The group then enters the nucleus, alerting the cell to the problem and initiating nerve regeneration.