A model of calcium channels

被引:30
作者
Corry, B
Allen, TW
Kuyucak, S
Chung, SH [1 ]
机构
[1] Australian Natl Univ, Res Sch Phys Sci, Dept Chem, Prot Dynam Univ, Canberra, ACT 0200, Australia
[2] Australian Natl Univ, Res Sch Phys Sci, Dept Theoret Phys, Canberra, ACT 0200, Australia
来源
BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES | 2000年 / 1509卷 / 1-2期
基金
英国医学研究理事会; 澳大利亚研究理事会;
关键词
calcium channel; modelling; permeation; selectivity; Brownian dynamics; electrostatics;
D O I
10.1016/S0005-2736(00)00330-8
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
We propose a model of calcium channels that can explain most of their observed properties, including the anomalous mole fraction effect and mutation of the glutamate residues. The structure grossly resembles that of the KcsA potassium channel except for the presence of an extracellular vestibule and a shorter selectivity filter containing four glutamate residues. Using this model in electrostatic calculations and Brownian dynamics simulations, we study mechanisms of ion permeation and selectivity in the channel. Potential energy profiles calculated for multiple ions in the channel provide explanations of ion permeation, the block of Na+ currents by Ca2+ ions, and many other observed properties. Brownian dynamics simulations provide quantitative predictions for the channel currents which reproduce available experimental data. (C) 2000 Elsevier Science B.V. All rights reserved.
引用
收藏
页码:1 / 6
页数:6
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