Homomeric GluA2(R) AMPA receptors can conduct when desensitized

Ian D. Coombs, David Soto, Thomas P. McGee, Matthew G. Gold, Mark Farrant () and Stuart G. Cull-Candy ()
Additional contact information
Ian D. Coombs: University College London
David Soto: University College London
Thomas P. McGee: University College London
Matthew G. Gold: University College London
Mark Farrant: University College London
Stuart G. Cull-Candy: University College London

Nature Communications, 2019, vol. 10, issue 1, 1-13

Abstract: Abstract Desensitization is a canonical property of ligand-gated ion channels, causing progressive current decline in the continued presence of agonist. AMPA-type glutamate receptors (AMPARs), which mediate fast excitatory signaling throughout the brain, exhibit profound desensitization. Recent cryo-EM studies of AMPAR assemblies show their ion channels to be closed in the desensitized state. Here we present evidence that homomeric Q/R-edited AMPARs still allow ions to flow when the receptors are desensitized. GluA2(R) expressed alone, or with auxiliary subunits (γ-2, γ-8 or GSG1L), generates large fractional steady-state currents and anomalous current-variance relationships. Our results from fluctuation analysis, single-channel recording, and kinetic modeling, suggest that the steady-state current is mediated predominantly by conducting desensitized receptors. When combined with crystallography this unique functional readout of a hitherto silent state enabled us to examine cross-linked cysteine mutants to probe the conformation of the desensitized ligand binding domain of functioning AMPAR complexes.

Date: 2019
References: Add references at CitEc
Citations: View citations in EconPapers (1)

Downloads: (external link)
https://www.nature.com/articles/s41467-019-12280-9 Abstract (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:natcom:v:10:y:2019:i:1:d:10.1038_s41467-019-12280-9

Ordering information: This journal article can be ordered from
https://www.nature.com/ncomms/

DOI: 10.1038/s41467-019-12280-9

Access Statistics for this article

Nature Communications is currently edited by Nathalie Le Bot, Enda Bergin and Fiona Gillespie

More articles in Nature Communications from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().