Hawkins R J, Bénichou O, Piel M, Voituriez R
UMR 7600, Université Pierre et Marie Curie/CNRS, 4 Place Jussieu, 75255 Paris Cedex 05, France.
Phys Rev E Stat Nonlin Soft Matter Phys. 2009 Oct;80(4 Pt 1):040903. doi: 10.1103/PhysRevE.80.040903. Epub 2009 Oct 19.
Many cellular processes require a polarization axis which generally initially emerges as an inhomogeneous distribution of molecular markers in the cell. We present a simple analytical model of a general mechanism of cell polarization taking into account the positive feedback due to the coupled dynamics of molecular markers and cytoskeleton filaments. We find that the geometry of the organization of cytoskeleton filaments, nucleated on the membrane (e.g., cortical actin) or from a center in the cytoplasm (e.g., microtubule asters), dictates whether the system is capable of spontaneous polarization or polarizes only in response to external asymmetric signals. Our model also captures the main features of recent experiments of cell polarization in two considerably different biological systems, namely, mating budding yeast and neuron growth cones.
许多细胞过程都需要一个极化轴，该极化轴通常最初表现为细胞内分子标记的不均匀分布。我们提出了一个细胞极化一般机制的简单分析模型，该模型考虑了分子标记和细胞骨架细丝耦合动力学引起的正反馈。我们发现，在膜上成核（例如，皮质肌动蛋白）或从细胞质中心（例如，微管星状体）成核的细胞骨架细丝的组织几何形状决定了系统是否能够自发极化，或者是否仅响应外部不对称信号而极化。我们的模型还捕捉到了两个截然不同的生物系统中细胞极化近期实验的主要特征，即交配出芽酵母和神经元生长锥。
