利用一种常见驱动蛋白(1BG2)和微管蛋白(1TUB)的结晶结构,通过静电计算得到了马达头部和微管蛋白表面的电势分布,并对比晶体结构分析了微管势场对马达头部正电势区域的作用.此外,利用解泊松方程的方法计算了驱动蛋白与微管间的静电相互作用,并发现马达沿微管轴向运动时所处的微管电势场具有周期性,其周期与马达步进周期有很好的一致性.最后,结合计算结果提出了驱动蛋白在静电作用下的运动机制.
Based on the crystal structure of a kinesin motor(1BG2)and tubulin(1TUB),the electric potential distribution on the surface of the motor head and the tubulin is obtained by electrostatic calculation,and the electrostatic interactions between the microtubule and the positive potential regions of kinesin are analyzed by comparing the crystal structures of them.Furthermore,through simulation by solving Poisson's equation,the electrostatic interactions of kinesin along the microtubule have been calculated,the results show that microtubule provides a periodic potential field for motor movement,and the period is consistent with that of the kinesin steps.Then combined with the calculated results, we present the electrostatic mechanism of kinesin movement.
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