Neurotransmitter Funneling Optimizes Glutamate Receptor Kinetics

Alvin Yu, Héctor Salazar, Andrew J.R. Plested, Albert Y. Lau

Research output: Contribution to journalArticlepeer-review


Ionotropic glutamate receptors (iGluRs) mediate neurotransmission at the majority of excitatory synapses in the brain. Little is known, however, about how glutamate reaches the recessed binding pocket in iGluR ligand-binding domains (LBDs). Here we report the process of glutamate binding to a prototypical iGluR, GluA2, in atomistic detail using unbiased molecular simulations. Charged residues on the LBD surface form pathways that facilitate glutamate binding by effectively reducing a three-dimensional diffusion process to a spatially constrained, two-dimensional one. Free energy calculations identify residues that metastably bind glutamate and help guide it into the binding pocket. These simulations also reveal that glutamate can bind in an inverted conformation and also reorient while in its pocket. Electrophysiological recordings demonstrate that eliminating these transient binding sites slows activation and deactivation, consistent with slower glutamate binding and unbinding. These results suggest that binding pathways have evolved to optimize rapid responses of AMPA-type iGluRs at synapses. Yu et al. show that the ligand-binding domain of ionotropic glutamate receptors has structural features on its surface that guide the agonist glutamate to its binding site. This phenomenon serves to accelerate receptor activation.

Original languageEnglish (US)
Pages (from-to)139-149.e4
Issue number1
StatePublished - Jan 3 2018


  • electrophysiology
  • free energy
  • glutamate receptors
  • ligand binding
  • ligand-gated ion channels
  • molecular dynamics simulations

ASJC Scopus subject areas

  • Neuroscience(all)

Fingerprint Dive into the research topics of 'Neurotransmitter Funneling Optimizes Glutamate Receptor Kinetics'. Together they form a unique fingerprint.

Cite this