Curvature-Sensitive Kinesin Binding Can Explain Microtubule Ring Formation and Reveals Chaotic Dynamics in a Mathematical Model.
Curvature-Sensitive Kinesin Binding Can Explain Microtubule Ring Formation and Reveals Chaotic Dynamics in a Mathematical Model.
复制标题
曲率敏感驱动蛋白结合可以解释微管环的形成并揭示数学模型中的混沌动力学。
DOI：
10.1007/s11538-018-0505-4
复制
发表时间：
2018
影响因子：
3.5
通讯作者：
Pearce SP
中科院分区：
文献类型：
--
作者：
Pearce SP
微管是丝状管状蛋白质聚合物，其对于一系列细胞行为是必不可少的，并且通常在微米长度尺度上是直的。然而，在一些滑动试验中，微管在分子马达的地毯上移动，即使在没有交联蛋白的情况下，单个微管也可以形成紧密的弧或环。理解这种现象可能会为类似的高度弯曲的微管提供重要的解释，这些微管可以在经历神经变性的神经细胞中发现。我们提出了一个模型的滑行试验中，驱动蛋白移动的微管表面诱导环的形成，通过差分结合，证实了最近的研究结果，在解决方案中应用的马达蛋白驱动蛋白的突变版本能够锁定微管曲率。对于某些参数状态，我们的模型预测直微管和弯曲微管可以同时存在，作为稳定的稳态，正如实验所见。此外，发现不稳定的解决方案，其中微分结合波传播下来的微管，因为它滑过表面，这可能导致混沌运动。虽然这个模型解释了二维微管行为的实验滑动测定，它有可能被改编来解释神经细胞的病理卷曲。
Microtubules are filamentous tubular protein polymers which are essential for a range of cellular behaviour, and are generally straight over micron length scales. However, in some gliding assays, where microtubules move over a carpet of molecular motors, individual microtubules can also form tight arcs or rings, even in the absence of crosslinking proteins. Understanding this phenomenon may provide important explanations for similar highly curved microtubules which can be found in nerve cells undergoing neurodegeneration. We propose a model for gliding assays where the kinesins moving the microtubules over the surface induce ring formation through differential binding, substantiated by recent findings that a mutant version of the motor protein kinesin applied in solution is able to lock-in microtubule curvature. For certain parameter regimes, our model predicts that both straight and curved microtubules can exist simultaneously as stable steady states, as has been seen experimentally. Additionally, unsteady solutions are found, where a wave of differential binding propagates down the microtubule as it glides across the surface, which can lead to chaotic motion. Whilst this model explains two-dimensional microtubule behaviour in an experimental gliding assay, it has the potential to be adapted to explain pathological curling in nerve cells.