Hui C S
Biosystems. 1977 Apr;8(4):207-12. doi: 10.1016/0303-2647(77)90042-9.
The present information about gating current observed in squid giant axons points towards the distinct possibility of the current arising from the Debye relaxation of the carboxyl groups in the side chains of the globular proteins enclosing the ionic channels. These carboxyl groups form dipole chains stretching across the membrane. A dipole model is constructed to study the relaxation process under the assumption that the relaxation time tau of the dipoles is modified by dipole-dipole interaction. This model explains qualitatively some of the features of the asymmetric gating current, but is not indicative of any specific mechanism leading to the opening of the gates in the ionic channels. We speculate that the conformational change in the protein globules as a result of dipole reorientation would be the key to the mystery.
目前关于在枪乌贼巨大轴突中观察到的门控电流的信息表明，电流极有可能源于包围离子通道的球状蛋白质侧链中羧基的德拜弛豫。这些羧基形成横跨膜的偶极链。构建了一个偶极模型，以研究在偶极 - 偶极相互作用改变偶极弛豫时间τ的假设下的弛豫过程。该模型定性地解释了不对称门控电流的一些特征，但并未表明导致离子通道门打开的任何具体机制。我们推测，偶极重新定向导致的蛋白质球状体构象变化可能是解开谜团的关键。
