Mutant Mouse Gene Discovered — Possible Link Between Nerve Degeneration and Regeneration

James I. Morgan, Ph.D.
St. Jude Children's Research Hospital
R01ES10772

Background: A classic recessive mouse mutant model, known as Purkinje cell degeneration (PCD), is characterized by adult-onset degeneration of Purkinje neurons in the cerebellum, photoreceptors in the retina, other neural cells, and defective spermatogenesis. Previously the gene responsible for this defect had not been identified.

Advance: This team of investigators have identified mutations in the axotomy-induced gene, Nna1, as the cause of this condition. Their research shows that Nna1 encodes a putative nuclear protein containing a zinc carboxypeptidase domain initially identified by its induction in spinal motor neurons after injury and during axonal regeneration.

Implication: The discovery of the defective gene in these mice could shed light on the pathology of neurological diseases such as Alzheimer's and Parkinson's. It also has implications on the cause of retinitis pigmentosa and possibly male infertility. The discovery of the gene may help develop treatment for repairing nerve damage and protecting nerves against damage. The discovery may lead to a better treatments for nerve degenerating accidents, such as head injuries, and radiation-induced nerve damage in cancer treatment.

Citation: Fernandez-Gonzalez A, La Spada AR, Treadaway J, Higdon JC, Harris BS, Sidman RL, Morgan JI, Zuo J. Purkinje cell degeneration (pcd) phenotypes caused by mutations in the axotomy-induced gene, Nna1. Science. 2002 Mar 8;295(5561):1904-6.