Researchers say that utilizing mouse models to study mutations in a gene called dynein, required for the proper functioning of sensory nerve cells, may pave the way for better treatments for a human nerve disorder known as peripheral neuropathy.
Peripheral neuropathy is caused due to the damage to the nerves and nerve processes located outside the brain and spinal cord.
Dr. Brian Popko, Jack Miller Professor in Neurological Diseases at the University of Chicago Medical Center, says that a study has shown that mice with mutations in only one copy of a gene coding for one part of dynein protein have severe defects in proprioception, the ability to perceive the spatial orientation of body parts.
The researcher said that such defects led to a significant reduction in the number of sensory nerve cells in affected mice, besides causing early-onset locomotion problems in the mice's hind legs, a defect that appears to be quite similar to some human neuropathies.
"This gene codes for part of a multi-protein complex. So a mutation in any of these proteins, or disruption in the function of this multi-protein complex through some other mechanism, could also lead to very similar abnormalities" in human patients with sensory neuropathies, said Popko.
Dynein acts as a "cargo-transporter" that regulates neurons that transmit signals over huge distances, to carry molecules from the tip of the axon to the neuron's cell bodies.
Popko said that if the cargo-transporter get disturbed in some way, like due to a mutation, the neurons transmitting signals over "long distances" would suffer more.
"It's very common for neuropathies to affect neurons with the longer axons, for example those that innervate the legs and feet," said Popko.
It was suggested earlier that hereditary sensory neuropathy might be linked to disabled trafficking along the axons.
However, there have been mutations found in two genes forming a complex that is vital for survival of sensory neurons and which is believed to be transported along the neurons by dynein.
"This study lays the groundwork for the search for disruptions of this cargo transporting complex in human patients with sensory neuropathy", said the authors of the paper.
The study is published in the recent issue of the Journal of Neuroscience.