WWW.JNEUROSCI.ORG
-
The Journal of Neuroscience MBF Stereo Investigator
QUICK SEARCH:   [advanced]


     
-


HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP
The Journal of Neuroscience, June 20, 2007, 27(25):6800-6809; doi:10.1523/JNEUROSCI.0284-07.2007

This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Supplemental Data
Right arrow Submit an eLetter
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Wong, A. Y. C.
Right arrow Articles by Bowie, D.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Wong, A. Y. C.
Right arrow Articles by Bowie, D.

 Previous Article  |  Next Article 

Cellular/Molecular
Na+/Cl– Dipole Couples Agonist Binding to Kainate Receptor Activation

Adrian Y. C. Wong, David M. MacLean, and Derek Bowie

Department of Pharmacology and Therapeutics, McGill University, Montreal, Québec, Canada H3G 1Y6

Correspondence should be addressed to Dr. Derek Bowie, Department of Pharmacology and Therapeutics, McIntyre Medical Sciences Building, Room 1317, McGill University, 3655 Promenade Sir William Osler, Montreal, Québec, Canada H3G 1Y6. Email: derek.bowie{at}mcgill.ca

Kainate-selective ionotropic glutamate receptors (GluRs) require external Na+ and Cl– as well as the neurotransmitter L-glutamate for activation. Although, external anions and cations apparently coactivate kainate receptors (KARs) in an identical manner, it has yet to be established how ions of opposite charge achieve this. An additional complication is that KARs are subject to other forms of cation modulation via extracellular acidification (i.e., protons) and divalent ions. Consequently, other cation species may compete with Na+ to regulate the time KARs remain in the open state. Here we designed experiments to unravel how external ions regulate GluR6 KARs. We show that GluR6 kinetics are unaffected by alterations in physiological pH but that divalent and alkali metal ions compete to determine the time course of KAR channel activity. Additionally, Na+ and Cl– ions coactivate GluR6 receptors by establishing a dipole, accounting for their common effect on KARs. Using charged amino acids as tethered ions, we further demonstrate that the docking order is fixed with cations binding first, followed by anions. Together, our findings identify the dipole as a novel gating feature that couples neurotransmitter binding to KAR activation.

Key words: glutamate receptor; cation; anion; desensitization; gating; proton

Received Oct. 11, 2006; revised May 17, 2007; accepted May 18, 2007.

Correspondence should be addressed to Dr. Derek Bowie, Department of Pharmacology and Therapeutics, McIntyre Medical Sciences Building, Room 1317, McGill University, 3655 Promenade Sir William Osler, Montreal, Québec, Canada H3G 1Y6. Email: derek.bowie{at}mcgill.ca






-

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help
-
Copyright 2008 by Society for Neuroscience ONLINE ISSN: 1529-2401
-