Mutational analysis of the charge selectivity filter of the α7 nicotinic acetylcholine receptor
Mutational analysis of the charge selectivity filter of the α7 nicotinic acetylcholine receptor
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DOI：
10.1016/s0896-6273(00)80741-2
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发表时间：
1999-04-01
期刊：
影响因子：
16.2
通讯作者：
Bertrand, D
中科院分区：
文献类型：
--
作者：
Corringer, PJ;Bertrand, S;Bertrand, D
在α 7烟碱乙酰胆碱受体中，我们分析了突变E237 A和V251 T以及脯氨酸插入P236 '在电荷选择性从阳离子到阴离子的转换中的贡献。我们发现，三重突变体表现出自发开放显示阴离子选择性。此外，在位置251处，亲水性或甚至带负电荷的残基与阴离子通道相容。相比之下，额外的脯氨酸产生阴离子通道，只有当插入之间的位置234和237;插入前234产生阳离子通道和后238改变受体表面的表达。卷曲的234-238环因此直接有助于α 7通道的电荷选择性过滤。
In the alpha 7 nicotinic acetylcholine receptors, we analyze the contribution of mutations E237A and V251T, together with the proline insertion P236', in the conversion of the charge selectivity from cationic to anionic. We show that the triple mutant exhibits spontaneous openings displaying anionic selectivity. Furthermore, at position 251, hydrophilic or even negatively charged residues are compatible with an anionic channel. In contrast, the additional proline yields an anionic channel only when inserted between positions 234 and 237; insertion before 234 yields a cationic channel and after 238 alters the receptor surface expression. The coiled 234-238 loop thus directly contributes to the charge selectivity filter of the alpha 7 channel.