Spontaneous cell polarization through actomyosin-based delivery of the Cdc42 GTPase
Spontaneous cell polarization through actomyosin-based delivery of the Cdc42 GTPase
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DOI：
10.1126/science.1080944
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发表时间：
2003-02-21
期刊：
影响因子：
56.9
通讯作者：
Li, R
中科院分区：
文献类型：
--
作者：
Wedlich-Soldner, R;Altschuler, SJ;Li, R
细胞极化可以在没有任何空间线索的情况下发生。为了研究自发细胞极化的机制，我们在酵母中使用了一种激活形式的CDC42的表达，这是一种细胞极化所需的Rho型鸟苷三磷酸酶(GTPase)，可以在不依赖任何预先建立的物理线索的情况下产生细胞极性。在本实验中，cdc42的极性分布需要肌动蛋白细胞骨架的定向分泌。数学模拟表明，通过一个正反馈回路可以产生一个稳定的极轴，在该回路中，质膜上活化的CdC42的局部浓度的随机增加增加了肌动蛋白聚合的几率，并增加了进一步积累到该位置的几率。
Cell polarization can occur in the absence of any spatial cues. To investigate the mechanism of spontaneous cell polarization, we used an assay in yeast where expression of an activated form of Cdc42, a Rho-type guanosine triphosphatase (GTPase) required for cell polarization, could generate cell polarity without any recourse to a preestablished physical cue. The polar distribution of Cdc42 in this assay required targeted secretion directed by the actin cytoskeleton. A mathematical simulation showed that a stable polarity axis could be generated through a positive feedback loop in which a stochastic increase in the local concentration of activated Cdc42 on the plasma membrane enhanced the probability of actin polymerization and increased the probability of further Cdc42 accumulation to that site.