We explore correlations between dynamics of different microtubules in a bundle, via numerical simulations, using a one-dimensional stochastic model of a microtubule. The guanosine triphosphate (GTP)-bound tubulins undergo diffusion-limited binding to the tip. Random hydrolysis events take place along the microtubule and converts the bound GTP in tubulin to guanosine diphosphate (GDP). The microtubule starts depolymerising when the monomer at the tip becomes GDP-bound; in this case, detachment of GDP-tubulin ensues and continues until either GTP-bound tubulin is exposed or complete depolymerisation is achieved. In the latter case, the microtubule is defined to have undergone a "catastrophe". Our results show that, in general, the dynamics of growth and catastrophe in different microtubules are coupled to each other; the closer the microtubules are, the stronger the coupling. In particular, all microtubules grow slower, on average, when brought closer together. The reduction in growth velocity also leads to more frequent catastrophes. More dramatically, catastrophe events in the different microtubules forming a bundle are found to be correlated; a catastrophe event in one microtubule is more likely to be followed by a similar event in the same microtubule. This propensity of bunching disappears when the microtubules move farther apart.

中文翻译：

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微管束中的巨灾事件之间的时空相关性：一项计算研究。

我们使用微管的一维随机模型，通过数值模拟，探索束中不同微管动力学之间的相关性。结合了鸟苷三磷酸（GTP）的微管蛋白经过扩散限制结合到尖端。沿着微管发生随机水解事件，并将微管蛋白中结合的GTP转化为鸟苷二磷酸（GDP）。当尖端的单体与GDP结合时，微管开始解聚。在这种情况下，GDP-微管蛋白随之脱离，并一直持续到与GTP结合的微管蛋白暴露或完全解聚为止。在后一种情况下，微管被定义为经历了“大灾难”。我们的结果表明，一般而言，不同微管中生长和灾难的动力学是相互耦合的。微管越近，耦合越强。特别是，将所有微管放在一起时，平均而言，它们的生长平均较慢。生长速度的降低也导致更频繁的灾难。更明显的是，发现形成束的不同微管中的灾难事件是相关的。在一个微管中发生灾难性事件的可能性更高，而在同一微管中发生类似事件的可能性更高。当微管移开更远时，这种聚束的倾向消失了。在一个微管中发生灾难性事件的可能性更高，而在同一微管中发生类似事件的可能性更高。当微管移开更远时，这种聚束的倾向消失了。在一个微管中发生灾难性事件的可能性更高，而在同一微管中发生类似事件的可能性更高。当微管移开更远时，这种聚束的倾向消失了。