Mice with a mutation in the dynein heavy chain 1 gene display sensory neuropathy but lack motor neuron disease.

Abstract

In neurons, cytoplasmic dynein functions as a molecular motor responsible for retrograde axonal transport. An impairment of axonal transport is thought to play a key role in the pathogenesis of neurodegenerative diseases such as amyotrophic lateral sclerosis, the most frequent motor neuron disease in the elderly. In this regard, previous studies described two heterozygous mouse strains bearing missense point mutations in the dynein heavy chain 1 gene that were reported to display late-onset progressive motor neuron degeneration. Here we show, however, that one of these mutant strains, the so-called Cra mice does not suffer from motor neuron loss, even in aged animals. Consistently, we did not observe electrophysiological or biochemical signs of muscle denervation, indicative of motor neuron disease. The "hindlimb clasping" phenotype of Cra mice could rather be due to the prominent degeneration of sensory neurons associated with a loss of muscle spindles. Altogether, these findings show that dynein heavy chain mutation triggers sensory neuropathy rather than motor neuron disease.

• Authors: Luc Dupuis, Anissa Fergani, Kerstin E Braunstein, Judith Eschbach, Nathalie Holl, Frédérique Rene, Jose-Luis Gonzalez De Aguilar, Björn Zoerner, Birgit Schwalenstocker, Albert C Ludolph, Jean-Philippe Loeffler
• Journal: Experimental neurology (Exp Neurol) Vol. 215 Issue 1 Pg. 146-52 (Jan 2009) ISSN: 1090-2430 [Electronic] United States
• PMID: 18952079 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Benzofurans
• Dync1h1 protein, mouse
• true blue
• Sod1 protein, mouse
• Superoxide Dismutase
• Superoxide Dismutase-1
• Choline O-Acetyltransferase
• Cytoplasmic Dyneins
• Dyneins

Topics

• Age Factors
• Analysis of Variance
• Animals
• Benzofurans
• Choline O-Acetyltransferase (metabolism)
• Cytoplasmic Dyneins
• Disease Models, Animal
• Dyneins (genetics)
• Electromyography (methods)
• Mice
• Mice, Inbred C3H
• Mice, Mutant Strains
• Motor Neuron Disease (genetics, physiopathology)
• Motor Neurons (pathology)
• Muscle Denervation (methods)
• Muscle, Skeletal (physiology)
• Mutation (genetics)
• Neuromuscular Junction (pathology)
• Sensation Disorders (genetics, pathology, physiopathology)
• Spinal Nerve Roots (pathology)
• Superoxide Dismutase (genetics)
• Superoxide Dismutase-1