Referenced in: none

Automatically associated channels: Kv10.1

Title: Molecular basis for convergent evolution of glutamate recognition by pentameric ligand-gated ion channels.

Authors: Timothy Lynagh, Robin N Beech, Maryline J Lalande, Kevin Keller, Brett A Cromer, Adrian J Wolstenholme, Bodo Laube

Journal, date & volume: Sci Rep, 2015 , 5, 8558

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/25708000

Abstract
Glutamate is an indispensable neurotransmitter, triggering postsynaptic signals upon recognition by postsynaptic receptors. We questioned the phylogenetic position and the molecular details of when and where glutamate recognition arose in the glutamate-gated chloride channels. Experiments revealed that glutamate recognition requires an arginine residue in the base of the binding site, which originated at least three distinct times according to phylogenetic analysis. Most remarkably, the arginine emerged on the principal face of the binding site in the Lophotrochozoan lineage, but 65 amino acids upstream, on the complementary face, in the Ecdysozoan lineage. This combined experimental and computational approach throws new light on the evolution of synaptic signalling.