Agonist-activated ionic channels in acetylcholine receptor reconstituted into planar lipid bilayers.
Agonist-activated ionic channels in acetylcholine receptor reconstituted into planar lipid bilayers.
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乙酰胆碱受体中激动剂激活的离子通道重构为平面脂质双层。
DOI：
10.1073/pnas.78.6.3586
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发表时间：
1981
影响因子：
11.1
通讯作者：
A. Maelicke
中科院分区：
文献类型：
--
作者：
G. Boheim;W. Hanke;F. Barrantes;H. Eibl;B. Sakmann;G. Fels;A. Maelicke
混合链磷脂1-硬脂酰-3-肉豆蔻酰甘油-2-磷酸胆碱形成平面脂质双层。乙酰胆碱受体膜片段或纯化的受体蛋白被纳入这些双层融合受体含有囊泡与平面膜几度低于脂质相变温度。单通道电流激活的烟碱激动剂在重建系统中观察到的完整的大鼠和青蛙的肌肉膜膜片钳技术所测量的类似。所观察到的通道特性不依赖于受体纯化的程度。因此，富含受体的片段和那些耗尽的非受体外周肽，纯化的受体单体/二聚体混合物，和分离的受体单体，如凝胶电泳所定义的合成脂质双层中的所有共享相似的电化学性质。因此，激动剂激活的离子通道似乎包含在受体单体中。
Planar lipid bilayers were formed with the mixed chain phospholipid 1-stearoyl-3-myristolglycero-2-phosphocholine. Acetylcholine receptor membrane fragments or the purified receptor protein was incorporated into these bilayers by fusing receptor-containing vesicles with the planar membranes a few degrees below the lipid phase transition temperature. Single-channel currents activated by nicotinic agonists in the reconstituted system resembled those observed in intact rat and frog muscle membrane as measured by the patch clamp technique. The observed channel characteristics did not depend on the degree of receptor purification. Thus, the receptor-enriched fragments and those depleted of nonreceptor peripheral peptides, the purified receptor monomer/dimer mixtures, and the isolated receptor monomer as defined by gel electrophoresis all shared similar electrochemical properties in the synthetic lipid bilayer. The agonist-activated ionic channel seems, therefore, to be contained within the receptor monomer.