Department of Theoretical Physics & Center for Biophysics, Saarland University, 66123 Saarbrücken, Germany.
Phys Rev Lett. 2020 May 15;124(19):198103. doi: 10.1103/PhysRevLett.124.198103.
Within cells, vesicles and proteins are actively transported several micrometers along the cytoskeletal filaments. The transport along microtubules is propelled by dynein and kinesin motors, which carry the cargo in opposite directions. Bidirectional intracellular transport is performed with great efficiency, even under strong confinement, as for example in the axon. For this kind of transport system, one would expect generically cluster formation. In this Letter, we discuss the effect of the recently observed self-enhanced binding affinity along the kinesin trajectories on the microtubule. We introduce a stochastic lattice-gas model, where the enhanced binding affinity is realized via a floor field. From Monte Carlo simulations and a mean-field analysis we show that this mechanism can lead to self-organized symmetry breaking and lane formation that indeed leads to efficient bidirectional transport in narrow environments.
在细胞内，囊泡和蛋白质沿着细胞骨架丝被主动运输几微米。沿着微管的运输是由动力蛋白和驱动蛋白马达推动的，它们携带货物向相反的方向运动。即使在强烈的限制下，如在轴突中，双向细胞内运输也能以很高的效率进行。对于这种运输系统，人们通常会预期形成簇。在这封信中，我们讨论了最近观察到的沿驱动蛋白轨迹的自增强结合亲和力对微管的影响。我们引入了一个随机格气模型，其中通过地板场实现增强的结合亲和力。通过蒙特卡罗模拟和平均场分析，我们表明这种机制可以导致自组织的对称破缺和车道形成，从而在狭窄的环境中实现有效的双向运输。
