在门酸通道中的球链无活化
Chen Fan1, Nattakan Sukomon1, Emelie Flood2
1Department of Anesthesiology, Weill Cornell Medical College, New York, NY, USA.
Nature
|April 10, 2020
概括
离子通道无活化,对于神经信号传递至关重要,由一个解释.
科学领域:
- 分子生物学分子生物学
- 生物物理学的生物物理.
- 神经科学是一个神经科学.
背景情况:
- 离子通道不活化在持续刺激期间终止了离子流.
- 这一过程对于神经元中的动作潜能生成和发射频率调节至关重要.
- 涉及堵塞毛孔的"球链"机制是假设的失活方法.
研究的目的:
- 为了阐明激活通道的分子封闭机制.
- 确定MthK通道中无活化的结构基础.
- 调查N端在通道不活化中的作用.
主要方法:
- 低温电子显微镜 (cryo-EM) 用于获得通道结构.
- 原子模拟用于分析通道灵活性和动态.
- 自由能量模拟用于评估相互作用强度.
- 功能性测定涉及N-终端删除突变.
主要成果:
- 获得了MthK通道在封闭状态和多个开放状态的不活化状态的结构.
- 道动态包括门环摇摆和孔外螺旋曲.
- 鉴定出N端是无活化机制中的孔隙堵塞"球".
- 取消了N端删除,取消了无活化和毛孔堵塞.
结论:
- 该N终端作为"球"在一个"球和链"机制MthK通道失活的"球".
- 道无活化涉及动态形状变化,包括封闭环移动和N端孔堵塞.
- 这项研究提供了对离子通道失活的分子理解.
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