edoc

GABA(B)-receptor subtypes assemble into functional heteromeric complexes

Kaupmann, K. and Malitschek, B. and Schuler, V. and Heid, J. and Froestl, W. and Beck, P. and Mosbacher, J. and Bischoff, S. and Kulik, A. and Shigemoto, R. and Karschin, A. and Bettler, B.. (1998) GABA(B)-receptor subtypes assemble into functional heteromeric complexes. Nature, Vol. 396, H. 6712. pp. 683-687.

Full text not available from this repository.

Official URL: http://edoc.unibas.ch/dok/A5262285

Downloads: Statistics Overview

Abstract

B-type receptors for the neurotransmitter GABA (gamma-aminobutyric acid) inhibit neuronal activity through G-protein-coupled second-messenger systems, which regulate the release of neurotransmitters and the activity of ion channels and adenylyl cyclase. Physiological and biochemical studies show that there are differences in drug efficiencies at different GABA(B) receptors, so it is expected that GABA(B)-receptor (GABA(B)R) subtypes exist. Two GABA(B)-receptor splice variants have been cloned (GABA(B)R1a and GABA(B)R1b), but native GABA(B) receptors and recombinant receptors showed unexplained differences in agonist-binding potencies. Moreover, the activation of presumed effector ion channels in heterologous cells expressing the recombinant receptors proved difficult. Here we describe a new GABA(B) receptor subtype, GABA(B)R2, which does not bind available GABA(B) antagonists with measurable potency. GABA(B)R1a, GABA(B)R1b and GABA(B)R2 alone do not activate Kir3-type potassium channels efficiently, but co-expression of these receptors yields a robust coupling to activation of Kir3 channels. We provide evidence for the assembly of heteromeric GABA(B) receptors in vivo and show that GABA(B)R2 and GABA(B)R1a/b proteins immunoprecipitate and localize together at dendritic spines. The heteromeric receptor complexes exhibit a significant increase in agonist- and partial-agonist-binding potencies as compared with individual receptors and probably represent the predominant native GABA(B) receptor. Heteromeric assembly among G-protein-coupled receptors has not, to our knowledge, been described before.
Faculties and Departments:03 Faculty of Medicine > Departement Biomedizin > Division of Physiology > Molecular Neurobiology Synaptic Plasticity (Bettler)
UniBasel Contributors:Bettler, Bernhard
Item Type:Article, refereed
Article Subtype:Research Article
Bibsysno:Link to catalogue
Publisher:Macmillan
ISSN:0028-0836
Note:Publication type according to Uni Basel Research Database: Journal article
Related URLs:
Identification Number:
Last Modified:22 Mar 2012 14:23
Deposited On:22 Mar 2012 13:36

Repository Staff Only: item control page