Conotoxin MI inhibits the α-δ acetylcholine binding site of the Torpedo marmorata receptor

被引：5

作者：

Cortez, LM ^{[1
]}

del Canto, SG ^{[1
]}

Testai, FD ^{[1
]}

Bonino, MJBD ^{[1
]}

机构：

[1] Univ Buenos Aires, Fac Farm & Bioquim, Inst Quim & Fisicoquim Biol, Dept Quim Biol,CONICET, RA-1113 Buenos Aires, DF, Argentina

来源：

BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS | 2002年 / 295卷 / 04期

关键词：

Torpedo marmorata; nicotinic receptors; alpha-conotoxin MI; ligand binding sites; Conus;

D O I：

10.1016/S0006-291X(02)00758-1

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

The muscle-type nicotinic receptor has two pharmacologically distinguishable acetylcholine binding sites at the alpha-gamma and alpha-delta subunit interfaces; alpha-conotoxins can bind them selectively. As reported, alpha-conotoxin MI has greater affinity for the site near the alpha-delta interface of the BC3HI cell receptor but. in the case of the Torpedo californica receptor, displays greater affinity for that near the interface. To further investigate ligand selectivity, we study the conotoxin MI-Torpedo marmorata receptor interaction. In this work, we show the binding of alpha-conotoxin MI to the T marmorata receptor and the influence of the antagonist alpha-Bungarotoxin and the agonist carbamylcholine on such binding; in addition, and contrasting, with the results for the Torpedo californica receptor. we identify the alpha-delta subunit interface as the high affinity binding site. This is the first work describing different characteristics of the interaction between alpha-conotoxin MI and receptors from different species of the same genus. (C) 2002 Elsevier Science (USA). All rights reserved.

引用

页码：791 / 795

页数：5

共 20 条

[1] MOLECULAR-BASIS OF THE 2 NONEQUIVALENT LIGAND-BINDING SITES OF THE MUSCLE NICOTINIC ACETYLCHOLINE-RECEPTOR [J].