Bentil D E
Department of Mathematics and Statistics, University of Vermont, Burlington 05401, USA.
J Comput Biol. 1998 Spring;5(1):73-86. doi: 10.1089/cmb.1998.5.73.
We present a model mechanism for simulating the diffusive motion and fluctuations inherent in myofibrillar sarcomere and its subunits at the molecular level. The model couples Langevin dynamics with Huxley kinetics to reproduce the transient patterns of momentum transfer, force generation and resulting motility due to the interactive activities of actin and myosin crossbridges. When myosin is detached from actin, our model predicts Brownian displacements centered at 0 +/- 8 nm (mean +/- SD, n = 265,308) and it is broadly distributed due to the Brownian noise. Attachment events produced displacements with step sizes of approximately 8 +/- 6 nm (mean +/- SD, n = 34,693), which is in agreement with some recent optical-tweezers transducer experimental results. The proposed model could form the basis for a complete qualitative and quantitative description of the evolving complex interactions of the molecular proteins--actin and myosin--in the overall framework of muscular contraction studies.
我们提出了一种模型机制，用于在分子水平上模拟肌原纤维肌节及其亚基固有的扩散运动和涨落。该模型将朗之万动力学与赫胥黎动力学相结合，以再现由于肌动蛋白和肌球蛋白横桥的相互作用活动而产生的动量传递、力产生及由此导致的运动的瞬态模式。当肌球蛋白与肌动蛋白分离时，我们的模型预测布朗位移以0 +/- 8 nm为中心（平均值 +/- 标准差，n = 265,308），并且由于布朗噪声而广泛分布。附着事件产生的位移步长约为8 +/- 6 nm（平均值 +/- 标准差，n = 34,693），这与最近一些光镊传感器实验结果一致。所提出的模型可为在肌肉收缩研究的整体框架中对分子蛋白——肌动蛋白和肌球蛋白——不断演变的复杂相互作用进行完整的定性和定量描述奠定基础。
