Lattice-gas model for active vesicle transport by molecular motors with opposite polarities
Lattice-gas model for active vesicle transport by molecular motors with opposite polarities
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DOI：
10.1103/physreve.82.021925
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发表时间：
2010-08-30
影响因子：
2.4
通讯作者：
Pagonabarraga, Ignacio
中科院分区：
文献类型：
--
作者：
Muhuri, Sudipto;Pagonabarraga, Ignacio
我们介绍了一个多物种格子气模型的马达蛋白驱动的集体货物运输的细胞丝。我们用这个模型来描述和分析集体运动的相互作用的囊泡货物进行相反方向的分子马达，移动在一个单一的生物丝。建立在一个完全不对称的排斥过程来表征相互作用的货物的运动，我们允许与环境，输入和输出的质量交换在细丝边界和重点的相互转换率的作用，以及它们如何影响的方向性的净货物运输。我们量化的各种不同的竞争过程中的非平衡相图的影响。相互转换率的相互作用，允许通量反转和蒸发沉积过程，引入了定性的相图中的独特功能。我们观察制度的三相共存，相位重新进入的可能性，以及一个显着的灵活性，在不同的相边界如何转移，以响应控制参数的变化。该模型的移动稳态解允许货物囊泡的空间分布的不同可能性，从均匀分布的囊泡到极化分布，其特征在于不均匀性或冲击。在这个模型的框架内，由于内部监管而导致的电流逆转自然出现。我们相信，这个最小的模型将澄清集体囊泡运输的许多功能的理解，除了作为基础，为囊泡运输相关的各种体内情况下，建立更精确的定量模型。
We introduce a multispecies lattice-gas model for motor protein driven collective cargo transport on cellular filaments. We use this model to describe and analyze the collective motion of interacting vesicle cargos being carried by oppositely directed molecular motors, moving on a single biofilament. Building on a totally asymmetric exclusion process to characterize the motion of the interacting cargos, we allow for mass exchange with the environment, input, and output at filament boundaries and focus on the role of interconversion rates and how they affect the directionality of the net cargo transport. We quantify the effect of the various different competing processes in terms of nonequilibrium phase diagrams. The interplay of interconversion rates, which allow for flux reversal and evaporation-deposition processes, introduces qualitatively unique features in the phase diagrams. We observe regimes of three-phase coexistence, the possibility of phase re-entrance, and a significant flexibility in how the different phase boundaries shift in response to changes in control parameters. The moving steady-state solutions of this model allows for different possibilities for the spatial distribution of cargo vesicles, ranging from homogeneous distribution of vesicles to polarized distributions, characterized by inhomogeneities or shocks. Current reversals due to internal regulation emerge naturally within the framework of this model. We believe that this minimal model will clarify the understanding of many features of collective vesicle transport, apart from serving as the basis for building more exact quantitative models for vesicle transport relevant to various in vivo situations.