细胞骨架微管力化学耦合动态行为的理论与数值研究

项目名称： 细胞骨架微管力化学耦合动态行为的理论与数值研究

项目编号： No.31270989

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 生物科学

项目作者： 冯西桥

作者单位： 清华大学

项目金额： 85万元

中文摘要： 作为细胞骨架的一种主要组成单元，微管在细胞的生命活动中至关重要，也与多种疾病密切相关。本项目将基于微管复杂而精巧的几何结构，对其在不同生理条件下的力化学耦合动态行为进行理论分析和数值模拟。首先，根据统计力学和热力学，建立描述微管力化学耦合动态行为的理论框架。并以此为基础，进一步考虑微管的微观结构及其在动态演化过程中化学能和弹性变形能的相互转化，建立微管的粗粒化分子计算模型。利用该模型，研究微管的加聚和解聚行为，揭示微管动态行为的物理机制。进而在理论模型中引入微管结合蛋白（如正端跟踪蛋白）、离子浓度、外加载荷等，分析这些因素对微管动态行为的影响，从而理解在不同生理条件下微管动态行为的差异。此外，将统一微管的形核过程与后续的加聚和解聚过程，实现对微管生长全过程的模拟。本项研究将有助于理解微管的结构-性能-功能之间的内在联系，对于细胞有丝分裂、纤毛鞭毛的运动等问题的研究也有一定的帮助。

中文关键词： 微管；动力学过程；力化学耦合；构型演化；粗粒化方法

英文摘要： As a kind of cytoskeleton filaments, microtubules play a vital role in various physiological processes of cells and are closely relevant to many diseases. They have complicated and elegant structures and show some highly dynamic and mechanical-chemical coupled behaviors. The present project aims at investigating the dynamic processes of microtubules at different physiological conditions. Firstly, a theoretical framework will be constructed based on statistical mechanics and thermodynamics. By considering the GTP hydrolysis and their complex structures, a coarse-grained mechanochemical model will be built, which can characterize the transformation between chemical and mechanical energy in microtubules. Using this model, we will simulate the polymerizing and depolymerizing processes of microtubules and reveal the underlying mechanisms by analyzing the evolutions of conformation and energy. Secondly, the role of microtubule associated proteins, especially the plus end-tracking proteins, will be incorporated in the model to examine their influences and acting mechanisms on microtubule dynamics. Thirdly, the nucleation process of microtubules will be simulated and integrated with the modeled microtubule growth. A complete simulation of nucleation and the subsequent tubulin assembly and disassembly will be carried out

英文关键词： Microtubule；Dynamic process；Mechanochemical coupling；Conformation evolution；Coarsed-grained method