STARTLE DISEASE MUTATIONS REDUCE THE AGONIST SENSITIVITY OF THE HUMAN INHIBITORY GLYCINE RECEPTOR

Abstract

The receptor for the inhibitory neurotransmitter glycine is a member of the ligand-gated ion channel receptor superfamily. Point mutations in the gene encoding the alpha 1 subunit of the glycine receptor-channel complex (GlyR) have recently been identified in pedigrees with the autosomal dominant neurological disorder, startle disease (hyperekplexia). These mutations result in the substitution of leucine or glutamine for arginine 271. This charged residue is located near the ion channel region and is predicted to affect chloride permeation through the GlyR. We found little evidence for this role from the anion/cation selectivity and lack of pronounced rectification of currents flowing throug..