Structural highlights
Function
[GLIC_GLOVI] Cationic channel with similar permeabilities for Na(+) and K(+), that is activated by an increase of the proton concentration on the extracellular side. Displays no permeability for chloride ions. Shows slow kinetics of activation, no desensitization and a single channel conductance of 8 pS. Might contribute to adaptation to external pH change.[1]
Publication Abstract from PubMed
gamma-Aminobutyric acid receptors (GABAARs) are vital for controlling excitability in the brain. This is emphasized by the numerous neuropsychiatric disorders that result from receptor dysfunction. A critical component of most native GABAARs is the alpha subunit. Its transmembrane domain is the target for many modulators, including endogenous brain neurosteroids that impact anxiety, stress and depression, and for therapeutic drugs, such as general anesthetics. Understanding the basis for the modulation of GABAAR function requires high-resolution structures. Here we present the first atomic structures of a GABAAR chimera at 2.8-A resolution, including those bound with potentiating and inhibitory neurosteroids. These structures define new allosteric binding sites for these modulators that are associated with the alpha-subunit transmembrane domain. Our findings will enable the exploitation of neurosteroids for therapeutic drug design to regulate GABAARs in neurological disorders.
Crystal structures of a GABAA-receptor chimera reveal new endogenous neurosteroid-binding sites.,Laverty D, Thomas P, Field M, Andersen OJ, Gold MG, Biggin PC, Gielen M, Smart TG Nat Struct Mol Biol. 2017 Oct 2. doi: 10.1038/nsmb.3477. PMID:28967882[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Bocquet N, Prado de Carvalho L, Cartaud J, Neyton J, Le Poupon C, Taly A, Grutter T, Changeux JP, Corringer PJ. A prokaryotic proton-gated ion channel from the nicotinic acetylcholine receptor family. Nature. 2007 Jan 4;445(7123):116-9. Epub 2006 Dec 10. PMID:17167423 doi:10.1038/nature05371
- ↑ Laverty D, Thomas P, Field M, Andersen OJ, Gold MG, Biggin PC, Gielen M, Smart TG. Crystal structures of a GABAA-receptor chimera reveal new endogenous neurosteroid-binding sites. Nat Struct Mol Biol. 2017 Oct 2. doi: 10.1038/nsmb.3477. PMID:28967882 doi:http://dx.doi.org/10.1038/nsmb.3477
