Conformational changes during the gating of a potassium channel revealed by structural mass spectrometry.
Conformational changes during the gating of a potassium channel revealed by structural mass spectrometry.
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DOI：
10.1016/j.str.2010.04.012
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发表时间：
2010-07-14
期刊：
影响因子：
--
通讯作者：
Chance MR
中科院分区：
文献类型：
--
作者：
Gupta S;Bavro VN;D'Mello R;Tucker SJ;Vénien-Bryan C;Chance MR
钾离子通道是一种动态蛋白质，它能通过构象变化来调节钾离子跨膜流动。因此，理解这些通道的门控机制需要在其开放和闭合构象中探测通道结构的方法。放射性足迹法用于研究内向整流钾通道KirBac3.1的门控机制。将稳定在开放或闭合构象中的纯化蛋白质暴露于聚焦的同步加速器X射线束以毫秒时间尺度来修饰溶剂可接近的氨基酸侧链。使用高分辨率质谱法鉴定和定量这些修饰。然后使用在关闭和打开状态之间观察到的差异来揭示在通道门控期间发生的局部构象变化。这些结果为Kir通道的门控机制提供了支持，并展示了一种探测其他膜蛋白和离子通道的动态门控机制的新方法。
Potassium channels are dynamic proteins that undergo large conformational changes to regulate the flow of K+ ions across the cell membrane. Understanding the gating mechanism of these channels therefore requires methods for probing channel structure in both their open and closed conformations. Radiolytic footprinting is used to study the gating mechanism of the inwardly-rectifying potassium channel KirBac3.1. The purified protein stabilized in either open or closed conformations was exposed to focused synchrotron X-ray beams on millisecond timescales to modify solvent accessible amino acid side chains. These modifications were identified and quantified using high-resolution mass spectrometry. The differences observed between the closed and open states were then used to reveal local conformational changes that occur during channel gating. The results provide support for a proposed gating mechanism of the Kir channel and demonstrate a novel method of probing the dynamic gating mechanism of other integral membrane proteins and ion channels.
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影响因子：
7
作者：
Zhu, Yi;Guo, Tiannan;Sze, Siu Kwan
通讯作者：
Sze, Siu Kwan
DOI：
10.1126/science.1180310
发表时间：
2009-12-18
期刊：
Science (New York, N.Y.)
影响因子：
--
作者：
Tao X;Avalos JL;Chen J;MacKinnon R
通讯作者：
MacKinnon R
DOI：
10.1085/jgp.200709936
发表时间：
2008-05
期刊：
The Journal of general physiology
影响因子：
--
作者：
Tucker SJ;Baukrowitz T
通讯作者：
Baukrowitz T
影响因子：
4.8
作者：
Singh, Dev K.;Rosenhouse-Dantsker, Avia;Levitan, Irena
通讯作者：
Levitan, Irena
影响因子：
2.6
作者：
Kiselar, JG;Maleknia, SD;Chance, MR
通讯作者：
Chance, MR