开放通道噪声。I. 乙酰胆碱受体电流中的噪声表明存在构象波动。
Open channel noise. I. Noise in acetylcholine receptor currents suggests conformational fluctuations.
作者信息
Sigworth F J
出版信息
Biophys J. 1985 May;47(5):709-20. doi: 10.1016/S0006-3495(85)83968-0.
Abstract
The random passage of ions through an open channel is expected to result in shot noise fluctuations in the channel current. The patch-clamp technique now allows fluctuations of this size to be observed in single-channel currents. In the experiments reported here the acetylcholine-induced currents in cultured rat muscle cells were analyzed; fluctuations were found that were considerably larger than expected for shot noise. A low-frequency component, which was fitted with a Lorentzian, was examined in detail; it appears to arise from fluctuations in channel conductance of approximately 3% on a time scale of 1 ms. The characteristic relaxation time is voltage dependent and temperature dependent (Q10 approximately equal to 3) suggesting that the fluctuations arise from conformational fluctuations in the channel protein.
摘要
离子随机通过开放通道预计会导致通道电流出现散粒噪声波动。膜片钳技术现在能够观察到单通道电流中这种大小的波动。在本文报道的实验中，对培养的大鼠肌肉细胞中乙酰胆碱诱导的电流进行了分析；发现波动比散粒噪声预期的要大得多。详细研究了一个用洛伦兹函数拟合的低频成分；它似乎源于通道电导在1毫秒时间尺度上约3%的波动。特征弛豫时间与电压和温度有关（Q10约等于3），这表明波动源于通道蛋白的构象波动。
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本文引用的文献
1
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Biophys J. 1984 Jan;45(1):144-6. doi: 10.1016/S0006-3495(84)84142-9.
2
Acetylcholine-induced current in perfused rat myoballs.灌注大鼠肌球中的乙酰胆碱诱导电流。
J Gen Physiol. 1980 Mar;75(3):297-321. doi: 10.1085/jgp.75.3.297.
3
The internal dynamics of globular proteins.球状蛋白质的内部动力学。
CRC Crit Rev Biochem. 1981;9(4):293-349. doi: 10.3109/10409238109105437.
4
Agonists block currents through acetylcholine receptor channels.激动剂可阻断通过乙酰胆碱受体通道的电流。
Biophys J. 1984 Aug;46(2):277-83. doi: 10.1016/S0006-3495(84)84022-9.
5
Single-channel currents from acetylcholine receptors in embryonic chick muscle. Kinetic and conductance properties of gaps within bursts.来自胚胎小鸡肌肉中乙酰胆碱受体的单通道电流。爆发内间隙的动力学和电导特性。
Biophys J. 1984 Jan;45(1):187-98. doi: 10.1016/S0006-3495(84)84147-8.
6
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7
Flickering of a nicotinic ion channel to a subconductance state.烟碱型离子通道闪烁至亚电导状态。
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8
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10
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