Voltage sensor of ion channels and enzymes.
Voltage sensor of ion channels and enzymes.
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DOI：
10.1007/s12551-011-0061-8
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发表时间：
2012-03-01
影响因子：
--
通讯作者：
Latorre, Ramon
中科院分区：
文献类型：
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作者：
Gonzalez, Carlos;Contreras, Gustavo F;Latorre, Ramon
放置在细胞膜（二维环境）中，离子通道和酶能够感知电压。这些蛋白质如何能够检测跨膜电压的差异引起了人们的广泛关注，有时在过去几年中引起了激烈的争论。钠、Ca 2+和K+电压依赖性通道具有保守的带正电荷的跨膜（S4）区段，其响应于膜电压的变化而移动。在电压依赖性通道中，S4形成结构域的一部分，该结构域结晶为由通道形成蛋白的前四个跨膜（S1-S4）片段组成的明确结构，其被定义为电压传感器结构域（VSD）。室间隔缺损与孔结构域相关联，并且室间隔缺损运动在不同程度上与孔开口变构偶联，这取决于通道的类型。在通道激活过程中有多少电荷移动，它们移动了多少，以及哪些是介导VSD和孔域之间机电耦合的分子决定因素是我们在这里讨论的一些问题。然而，VSD本身可以作为真正的质子通道发挥作用，此外，VSD也可以是电压依赖性磷酸酶的功能部分。
Placed in the cell membrane (a two-dimensional environment), ion channels and enzymes are able to sense voltage. How these proteins are able to detect the difference in the voltage across membranes has attracted much attention, and at times, heated debate during the last few years. Sodium, Ca2+ and K+ voltage-dependent channels have a conserved positively charged transmembrane (S4) segment that moves in response to changes in membrane voltage. In voltage-dependent channels, S4 forms part of a domain that crystallizes as a well-defined structure consisting of the first four transmembrane (S1-S4) segments of the channel-forming protein, which is defined as the voltage sensor domain (VSD). The VSD is tied to a pore domain and VSD movements are allosterically coupled to the pore opening to various degrees, depending on the type of channel. How many charges are moved during channel activation, how much they move, and which are the molecular determinants that mediate the electromechanical coupling between the VSD and the pore domains are some of the questions that we discuss here. The VSD can function, however, as a bona fide proton channel itself, and, furthermore, the VSD can also be a functional part of a voltage-dependent phosphatase.