驱动蛋白颈链对接过程及其力产生机制的研究,是揭示驱动蛋白结构与功能的关系,认识生物体蛋白质中普遍存在的、高效的能量转化机制和精确的构象变化调控机制的一个基础性课题。本文中,我们对驱动蛋白颈链对接的过程及其力产生机制进行了系统地分析研究。通过分子动力学模拟,得到了处于空态的马达头部的合理结构。在此结构的基础上,通过对颈链对接的启动机制以及具体实现过程、ATP结合引起的马达头部转动到颈链对接过程力传递路径的分析,从动力学上实现了驱动蛋白颈链对接;澄清了颈链对接的启动机制、颈链向马达头部对接的实现机制、驱动蛋白向前行走时的力产生机制、以及驱动蛋白双头力学化学循环调控机制。对文中所讨论的一些关键问题,给出了实验验证的可能方案。本文的研究结果对理解驱动蛋白结构与功能关系、分子马达的力产生机制、做功原理和高效的能量转换机制有重要的参考价值。
Neck linker's docking process and the force generation mechanism of kinesin are the fundamental subjects for unveiling structure-function relation of kinesin, understanding the ubiq- uitous high efficient energy-transformation mechanism and the exqusite coordination mechanism in biological systems, as well as the basis of movements of biological molecules in life processes. In this paper, we systematically studied and analyzed such two subjects. With the aid of molec- ular dynamics simulations, we obtained the proper structure of kinesin's nucleotide-free leading head. Based on this structure, we analyzed the initiation mechanism and realization process of the neck linker's docking process, and the dynamical pathway from ATP binding induced motor head rotation to neck linker docking. We dynamically realized the neck linker's docking process of kinesin and clarified the initiation mechanism, realization mechanism of neck linker'docking process, the force generation mechanism and the gating mechanism in its mechanochemical cycle. We also proposed the possible experimental schemes to verify some key results found in our theo- retical discussions. We believe that the results reported in this paper provide voluble information for understanding the kinesin's structure-function relation, force generation mechanism, working principle and energy-transformation mechanism.