一个无序的片段的立体特异性结合介导了BK通道不活化
Vivian Gonzalez-Perez1, Xu-Hui Zeng, Katie Henzler-Wildman
1Department of Anesthesiology, Washington University School of Medicine, St Louis, Missouri 63110, USA.
Nature
|April 24, 2012
概括
本质上无序的蛋白质部分调解关键功能,如离子通道不活化. 这项研究揭示了两种不同的分子相互作用,即立体特异结合和直接封闭,这些基本的生物过程的基础.
科学领域:
- 分子生物学分子生物学
- 生物物理学的生物物理.
- 结构生物学是结构生物学.
背景情况:
- 内在无序的蛋白质区域 (IDRs) 调解细胞的基本功能,包括离子通道不活化.
- 蛋白质无活化涉及移动片段,阻断离子透,但分子机制尚未完全理解.
- 电压依赖的K+通道 (Kv) 和大导电性Ca2+门的K+ (BK) 通道表现出不同的无活化机制.
研究的目的:
- 调查离子通道中内在无序的片段介导的无活化背后的分子相互作用.
- 为了比较 Kv 通道和涉及无序片段的 BK 通道的无活化机制.
- 阐明立体特异结合在BK通道失活中的作用.
主要方法:
- 溶液核磁共振 (NMR) 光谱法,用于分析孤立无活化域的构造异质性.
- 在KV和BK通道中无活化动态的生物物理特征.
- 不活化的突变分析.
主要成果:
- 由无序β-亚单元介导的BK通道无活化涉及一个两步过程,在封锁之前有一个立体特异的结合相互作用.
- 震动器Kv通道的无活化与无显著的固体约束的疏水性段直接封闭相一致.
- 失序的片段表现出形状异质性,并且可以容忍突变而不会失去功能.
结论:
- 两个不同的分子相互作用类型,立体特异结合和直接封闭,通过无序的片段调解功能上类似的无活化过程.
- 了解这些机制,可以了解本质上混乱的区域是如何发挥功能作用的.
- 这些发现突出了无序蛋白质部分在生物调节中采用的多样化策略.
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