Re-connecting nerves after injury

Deleting a single gene in mice lets nerve cells regenerate their spindly arms—called axons—after injury, Yale researchers have discovered. In spinal cord injuries, nerve cells often remain alive but dysfunctional because of axon damage, and it is hoped that spurring the body to repair those axons can re-establish the transmission of nerve impulses through the body.

A team led by Stephen M. Strittmatter, MD, PhD, Vincent Coates Professor of Neurology and professor of neuroscience, set out to determine which of more than 16,000 mouse genes were linked to axon regrowth. They screened the mouse genome and then found, in vitro, an apparent ability to influence axonal growth in approximately 500 genes.

In the gene Rab27b, known to transport proteins within cells, they found a significant effect both in vitro and in vivo. When the team deleted Rab27 from mice, both cortical and optic nerve cells showed themselves to be especially effective at axonal regeneration after multiple types of trauma and injury.

The finding, published on April 10 in Cell Reports, could point toward novel ways of treating human spinal cord injuries.