Multi-ion conduction bands in a simple model of calcium ion channels.
Multi-ion conduction bands in a simple model of calcium ion channels.
复制标题
钙离子通道简单模型中的多离子导带。
DOI：
10.1088/1478-3975/10/2/026007
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发表时间：
2013
期刊：
影响因子：
2
通讯作者：
Kaufman I
中科院分区：
文献类型：
--
作者：
Kaufman I
我们报告的自洽布朗动力学模拟的一个简单的静电模型的选择性过滤器（SF）的钙离子通道。它们揭示了在SF的固定负电荷Q f的函数的电导和选择性的规则结构。随着Q f的增加，存在由几乎零电导的区域（阻带）分隔的高电导的不同区域（导带）M0、M1、M2。其中两个导带M1和M2分别与P= 1和P= 2的饱和钙占有率相关，并表现出自维持电导率。尽管该模型的局限性，其M1和M2带显示出高的钙选择性和突出的异常摩尔分数效应，并可以确定与L型和RyR钙通道。非选择性条带M0可以用非选择性阳离子通道或OmpF孔蛋白鉴定。
We report self-consistent Brownian dynamics simulations of a simple electrostatic model of the selectivity filters (SF) of calcium ion channels. They reveal regular structure in the conductance and selectivity as functions of the fixed negative charge Q f at the SF. With increasing Q f, there are distinct regions of high conductance (conduction bands) M0, M1, M2 separated by regions of almost zero-conductance (stop-bands). Two of these conduction bands, M1 and M2, are related to the saturated calcium occupancies of P= 1 and P= 2, respectively and demonstrate self-sustained conductivity. Despite the model's limitations, its M1 and M2 bands show high calcium selectivity and prominent anomalous mole fraction effects and can be identified with the L-type and RyR calcium channels. The non-selective band M0 can be identified with a non-selective cation channel, or with OmpF porin.