Patch coalescence as a mechanism for eukaryotic directional sensing
Patch coalescence as a mechanism for eukaryotic directional sensing
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DOI：
10.1103/physrevlett.99.158101
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发表时间：
2007-10-12
影响因子：
8.6
通讯作者：
Ortenzi, G.
中科院分区：
文献类型：
--
作者：
Gamba, A.;Kolokolov, I.;Ortenzi, G.
真核细胞拥有一个敏感的化学指南针，使它们能够定向到可溶性化学物质的来源。细胞外化学信号触发细胞膜分离成两个结构域，这两个结构域由不同的磷脂分子组成，并沿着信号各向异性取向。我们提出了一个理论，这个极化过程，这是阐明成后续阶段的胚芽成核，补丁粗化，并合并成一个单一的域。我们发现，极化时间t（th）依赖于各向异性程度，满足t（th）与各向异性程度成正比的幂律关系，并且在半径为R的单元中，对于最小的可检测各向异性，应该存在一个与R-1成正比的阈值。
Eukaryotic cells possess a sensible chemical compass allowing them to orient toward sources of soluble chemicals. The extracellular chemical signal triggers separation of the cell membrane into two domains populated by different phospholipid molecules and oriented along the signal anisotropy. We propose a theory of this polarization process, which is articulated into subsequent stages of germ nucleation, patch coarsening, and merging into a single domain. We find that the polarization time, t(epsilon), depends on the anisotropy degree epsilon through the power law t(epsilon)proportional to epsilon(-2), and that in a cell of radius R there should exist a threshold value epsilon(th)proportional to R-1 for the smallest detectable anisotropy.