有证据表明,通道封锁中存在合作性相互作用
1Department of Cellular and Molecular Physiology, Harvard Medical School, Boston, Massachusetts 02115.
Nature
|October 1, 1992
概括
这项研究揭示了电压门的通道不会独立地进入. 相反,个别的子单位合作,相互影响.
科学领域:
- 分子生物学分子生物学
- 离子通道生物物理 离子通道生物物理
- 神经科学是一个神经科学.
背景情况:
- 电压通道对于神经元刺激能力至关重要.
- 这些通道是相同子单元的四度体,每一个都有电压传感器.
- 电压传感器的形状变化被认为是通道开通之前的.
研究的目的:
- 为了调查电压门通道的单个子单元是否独立或合作地开门.
- 通过控制小单元固体测量来确定通道的封闭机制.
主要方法:
- 在单个多链上编码四个通道子单元的构造cDNA.
- 创建了具有不同组合子单元,表现出不同门表型的异构四体.
- 分析了这些工程道综合体的门行为.
主要成果:
- 异质四体的结表明了非独立的子单元行为.
- 证据强烈表明,各个子单位的关门是合作的,而不是独立的.
- 结果与通道封闭电流的动力测量结果一致.
结论:
- 电压关闭通道的单个子单元以合作方式关闭.
- 这种合作性关机制与其他多子单元蛋白质的观察结果一致.
- 这些发现挑战了通道中独立子单元关的假设.
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