Allosteric and hyperekplexic mutant phenotypes investigated on an α1 glycine receptor transmembrane structure
Abstract
Pentameric ligand-gated ion channels (pLGICs) mediate neuronal communication in the central nervous system. Upon the neurotransmitter binding, these receptors undergo a rapid conformational change to open an integral ion channel. Mutations impairing the function of pLGICs are known to cause hyperekplexic, myasthenic, and epileptic syndromes. Here, we studied how the local perturbations caused by single mutations result in an alteration of the protein function. Using a chimeric protein assembled by the transmembrane domain of the human glycine receptors fused to the extracellular domain of the bacterial pLGIC GLIC, we performed functional experiments in parallel with X-ray crystallography. On this basis, we propose a molecular mechanism for channel opening that accounts for the phenotypes of several mutants causing hyperekplexia.
- Publication:
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Proceedings of the National Academy of Science
- Pub Date:
- March 2015
- DOI:
- 10.1073/pnas.1417864112
- Bibcode:
- 2015PNAS..112.2865M