Rovira J C, Ballesta J J, Vicente-Agulló F, Campos-Caro A, Criado M, Sala F, Sala S
Departamento de Farmacología, Instituto de Neurociencias, Universidad Miguel Hernández, Campus de San Juan, Alicante, Spain.
FEBS Lett. 1998 Aug 14;433(1-2):89-92. doi: 10.1016/s0014-5793(98)00889-8.
An aspartate residue in the M2-M3 loop of neuronal nicotinic receptor alpha7 subunits is a major determinant of the channel functional response. This residue is conserved in most beta4 subunits, e.g. human and rat, but not in others, e.g. bovine. We have used these differences to examine the mechanism by which this residue alters the functional properties of alpha3beta4 receptors. Having ruled out an effect on the macroscopic binding ability of the agonist, the level of receptor expression, or the single channel conductance, the results suggest that receptors lacking that residue have a deficient coupling between binding and gating.
神经元烟碱型受体α7亚基M2-M3环中的一个天冬氨酸残基是通道功能反应的主要决定因素。该残基在大多数β4亚基中保守，如人和大鼠，但在其他亚基中不保守，如牛。我们利用这些差异来研究该残基改变α3β4受体功能特性的机制。排除对激动剂宏观结合能力、受体表达水平或单通道电导的影响后，结果表明缺乏该残基的受体在结合和门控之间存在耦合缺陷。
