RRC ID 6310
Author Almedom RB, Liewald JF, Hernando G, Schultheis C, Rayes D, Pan J, Schedletzky T, Hutter H, Bouzat C, Gottschalk A.
Title An ER-resident membrane protein complex regulates nicotinic acetylcholine receptor subunit composition at the synapse.
Journal EMBO J
Abstract Nicotinic acetylcholine receptors (nAChRs) are homo- or heteropentameric ligand-gated ion channels mediating excitatory neurotransmission and muscle activation. Regulation of nAChR subunit assembly and transfer of correctly assembled pentamers to the cell surface is only partially understood. Here, we characterize an ER transmembrane (TM) protein complex that influences nAChR cell-surface expression and functional properties in Caenorhabditis elegans muscle. Loss of either type I TM protein, NRA-2 or NRA-4 (nicotinic receptor associated), affects two different types of muscle nAChRs and causes in vivo resistance to cholinergic agonists. Sensitivity to subtype-specific agonists of these nAChRs is altered differently, as demonstrated by whole-cell voltage-clamp of dissected adult muscle, when applying exogenous agonists or after photo-evoked, channelrhodopsin-2 (ChR2) mediated acetylcholine (ACh) release, as well as in single-channel recordings in cultured embryonic muscle. These data suggest that nAChRs desensitize faster in nra-2 mutants. Cell-surface expression of different subunits of the 'levamisole-sensitive' nAChR (L-AChR) is differentially affected in the absence of NRA-2 or NRA-4, suggesting that they control nAChR subunit composition or allow only certain receptor assemblies to leave the ER.
Volume 28(17)
Pages 2636-49
Published 2009-9-2
DOI 10.1038/emboj.2009.204
PII emboj2009204
PMID 19609303
PMC PMC2738700
MeSH Action Potentials Animals Animals, Genetically Modified Caenorhabditis elegans / metabolism Caenorhabditis elegans Proteins / genetics Caenorhabditis elegans Proteins / metabolism* Electrophysiology Endoplasmic Reticulum / metabolism* Humans Membrane Proteins / metabolism* Protein Subunits / metabolism* Receptors, Nicotinic / genetics Receptors, Nicotinic / metabolism* Synapses / metabolism*
IF 9.889
Times Cited 30
WOS Category BIOCHEMISTRY & MOLECULAR BIOLOGY CELL BIOLOGY
Resource
C.elegans tm1453 tm2656