How the interplay between mechanical and nonmechanical interactions affects multiple kinesin dynamics.
How the interplay between mechanical and nonmechanical interactions affects multiple kinesin dynamics.
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DOI：
10.1021/jp304018b
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发表时间：
2012-08-02
影响因子：
3.3
通讯作者：
Kolomeisky, Anatoly B.
中科院分区：
文献类型：
--
作者：
Uppulury, Karthik;Efremov, Artem K.;Driver, Jonathan W.;Jamison, D. Kenneth;Diehl, Michael R.;Kolomeisky, Anatoly B.
细胞内运输由称为运动蛋白的酶支持，这些酶通常与相同的货物偶联并共同发挥作用。最近的实验和理论进展已经能够通过阐明耦合电机之间的不平等负载分配如何改变它们的结合、步进和分离方式来解释多个电机系统的某些行为。然而，尽管一些研究表明微管结合的驱动蛋白通过短程非机械电位局部相互作用，但非机械相互作用通常被忽视。这项工作开发了一种新的随机模型，以探索除了机械耦合之外，这些类型的相互作用如何影响多种驱动蛋白功能。仅当马达被少于三个微管晶格位点分开时，非机械相互作用被认为影响驱动蛋白机械化学，并且表明相对较弱的相互作用能量（~2 kBT）可以对集体运动速度和脱离率产生明显影响。与结构定义的驱动蛋白复合物的光学捕获实验一致，该模型预测这些效应主要发生在货物运输超过单驱动蛋白失速力的负载时。总体而言，这些结果强调了影响集体运动功能的因素的相互依赖性质，即多运动系统的约束配置在负载下演变的方式决定了局部非机械相互作用如何影响运动合作。
Intracellular transport is supported by enzymes called motor proteins that are often coupled to the same cargo and function collectively. Recent experiments and theoretical advances have been able to explain certain behaviors of multiple motor systems by elucidating how unequal load sharing between coupled motors changes how they bind, step, and detach. However, non-mechanical interactions are typically overlooked despite several studies suggesting that microtubule-bound kinesins interact locally via short-range non-mechanical potentials. This work develops a new stochastic model to explore how these types of interactions influence multiple kinesin functions in addition to mechanical coupling. Non-mechanical interactions are assumed to affect kinesin mechanochemistry only when the motors are separated by less than three microtubule lattice sites, and it is shown that relatively weak interaction energies (~2 kBT) can have an appreciable influence over collective motor velocities and detachment rates. In agreement with optical trapping experiments on structurally-defined kinesin complexes, the model predicts that these effects primarily occur when cargos are transported against loads exceeding single-kinesin stalling forces. Overall, these results highlight the inter-dependent nature of factors influencing collective motor functions, namely, that the way the bound configuration of a multiple motor system evolves under load determines how local non-mechanical interactions influence motor cooperation.
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DOI：
10.1083/jcb.200908075
发表时间：
2009-12-28
期刊：
The Journal of cell biology
影响因子：
--
作者：
Ally S;Larson AG;Barlan K;Rice SE;Gelfand VI
通讯作者：
Gelfand VI
影响因子：
11.4
作者：
Seitz, A;Surrey, T
通讯作者：
Surrey, T
影响因子：
4
作者：
Hendricks, Adam G.;Epureanu, Bogdan I.;Meyhoefer, Edgar
通讯作者：
Meyhoefer, Edgar
影响因子：
4.8
作者：
Jamison, D. Kenneth;Driver, Jonathan W.;Diehl, Michael R.
通讯作者：
Diehl, Michael R.
影响因子：
3.3
作者：
Rogers, Arthur R.;Driver, Jonathan W.;Diehl, Michael R.
通讯作者：
Diehl, Michael R.