Molecular dissection of subunit interfaces in the acetylcholine receptor: Identification of determinants of α-Conotoxin M1 selectivity

Steven M Sine, Hans Jurgen Kreienkamp, Nina Bren, Robert Maeda, Palmer Taylor

Research output: Contribution to journalArticle

168 Citations (Scopus)

Abstract

The acetylcholine receptor from vertebrate skeletal muscle is a pentamer of homologous subunits with composition α2βγδ. Its two ligand binding sites, formed at α-γ and α-δ interfaces, differ in their affinities for agonists and competitive antagonists, owing to different contributions of the γ and δ subunits. To identify portions of the † and δ subunits that contribute to the binding sites, the experiments described here use γ-δ subunit chimeras and site-specific mutants to determine the basis of the 10,000-fold selectivity of conotoxin M1 for the sites. Three distinct regions of the extracellular domain were found to contribute to conotoxin M1 selectivity, each containing a single residue responsible for the contribution of that region. Residues K34, S111, and F172 of the γ subunit confer low affinity to the α-γ binding site, whereas the corresponding residues of the δ subunit, S36, Y113, and 1178, confer high affinity to the α-δ site. Identification of three separate determinants of ligand selectivity suggests a limited model of the folding pattern of the extracellular domain of the subunits.

Original languageEnglish (US)
Pages (from-to)205-211
Number of pages7
JournalNeuron
Volume15
Issue number1
DOIs
StatePublished - 1995

Fingerprint

Cholinergic Receptors
Dissection
Binding Sites
Ligands
Vertebrates
Skeletal Muscle
conotoxin MI

ASJC Scopus subject areas

  • Neuroscience(all)

Cite this

Molecular dissection of subunit interfaces in the acetylcholine receptor : Identification of determinants of α-Conotoxin M1 selectivity. / Sine, Steven M; Kreienkamp, Hans Jurgen; Bren, Nina; Maeda, Robert; Taylor, Palmer.

In: Neuron, Vol. 15, No. 1, 1995, p. 205-211.

Research output: Contribution to journalArticle

Sine, Steven M ; Kreienkamp, Hans Jurgen ; Bren, Nina ; Maeda, Robert ; Taylor, Palmer. / Molecular dissection of subunit interfaces in the acetylcholine receptor : Identification of determinants of α-Conotoxin M1 selectivity. In: Neuron. 1995 ; Vol. 15, No. 1. pp. 205-211.
@article{223f3e531db94c4ab7fd9d756d40d48f,
title = "Molecular dissection of subunit interfaces in the acetylcholine receptor: Identification of determinants of α-Conotoxin M1 selectivity",
abstract = "The acetylcholine receptor from vertebrate skeletal muscle is a pentamer of homologous subunits with composition α2βγδ. Its two ligand binding sites, formed at α-γ and α-δ interfaces, differ in their affinities for agonists and competitive antagonists, owing to different contributions of the γ and δ subunits. To identify portions of the † and δ subunits that contribute to the binding sites, the experiments described here use γ-δ subunit chimeras and site-specific mutants to determine the basis of the 10,000-fold selectivity of conotoxin M1 for the sites. Three distinct regions of the extracellular domain were found to contribute to conotoxin M1 selectivity, each containing a single residue responsible for the contribution of that region. Residues K34, S111, and F172 of the γ subunit confer low affinity to the α-γ binding site, whereas the corresponding residues of the δ subunit, S36, Y113, and 1178, confer high affinity to the α-δ site. Identification of three separate determinants of ligand selectivity suggests a limited model of the folding pattern of the extracellular domain of the subunits.",
author = "Sine, {Steven M} and Kreienkamp, {Hans Jurgen} and Nina Bren and Robert Maeda and Palmer Taylor",
year = "1995",
doi = "10.1016/0896-6273(95)90077-2",
language = "English (US)",
volume = "15",
pages = "205--211",
journal = "Neuron",
issn = "0896-6273",
publisher = "Cell Press",
number = "1",

}

TY - JOUR

T1 - Molecular dissection of subunit interfaces in the acetylcholine receptor

T2 - Identification of determinants of α-Conotoxin M1 selectivity

AU - Sine, Steven M

AU - Kreienkamp, Hans Jurgen

AU - Bren, Nina

AU - Maeda, Robert

AU - Taylor, Palmer

PY - 1995

Y1 - 1995

N2 - The acetylcholine receptor from vertebrate skeletal muscle is a pentamer of homologous subunits with composition α2βγδ. Its two ligand binding sites, formed at α-γ and α-δ interfaces, differ in their affinities for agonists and competitive antagonists, owing to different contributions of the γ and δ subunits. To identify portions of the † and δ subunits that contribute to the binding sites, the experiments described here use γ-δ subunit chimeras and site-specific mutants to determine the basis of the 10,000-fold selectivity of conotoxin M1 for the sites. Three distinct regions of the extracellular domain were found to contribute to conotoxin M1 selectivity, each containing a single residue responsible for the contribution of that region. Residues K34, S111, and F172 of the γ subunit confer low affinity to the α-γ binding site, whereas the corresponding residues of the δ subunit, S36, Y113, and 1178, confer high affinity to the α-δ site. Identification of three separate determinants of ligand selectivity suggests a limited model of the folding pattern of the extracellular domain of the subunits.

AB - The acetylcholine receptor from vertebrate skeletal muscle is a pentamer of homologous subunits with composition α2βγδ. Its two ligand binding sites, formed at α-γ and α-δ interfaces, differ in their affinities for agonists and competitive antagonists, owing to different contributions of the γ and δ subunits. To identify portions of the † and δ subunits that contribute to the binding sites, the experiments described here use γ-δ subunit chimeras and site-specific mutants to determine the basis of the 10,000-fold selectivity of conotoxin M1 for the sites. Three distinct regions of the extracellular domain were found to contribute to conotoxin M1 selectivity, each containing a single residue responsible for the contribution of that region. Residues K34, S111, and F172 of the γ subunit confer low affinity to the α-γ binding site, whereas the corresponding residues of the δ subunit, S36, Y113, and 1178, confer high affinity to the α-δ site. Identification of three separate determinants of ligand selectivity suggests a limited model of the folding pattern of the extracellular domain of the subunits.

UR - http://www.scopus.com/inward/record.url?scp=0029085766&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0029085766&partnerID=8YFLogxK

U2 - 10.1016/0896-6273(95)90077-2

DO - 10.1016/0896-6273(95)90077-2

M3 - Article

C2 - 7619523

AN - SCOPUS:0029085766

VL - 15

SP - 205

EP - 211

JO - Neuron

JF - Neuron

SN - 0896-6273

IS - 1

ER -