Asymmetry between pushing and pulling for crawling cells.
Asymmetry between pushing and pulling for crawling cells.
复制标题
爬行细胞的推和拉之间的不对称。
DOI：
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发表时间：
2013
期刊：
影响因子：
--
通讯作者：
L. Truskinovsky
中科院分区：
文献类型：
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作者：
P. Recho;L. Truskinovsky
真核细胞具有运动机制，使它们不仅能够自我推进，而且还能对障碍物施加力（推）和携带货物（拉）。为了研究主动推拉之间固有的不对称性，我们将爬行肌动蛋白细胞提取物建模为受外力作用的一维活性凝胶层。研究表明，推力受突出控制，突出主导运动机制的宏观特征是力-速度关系的凹凸性。相反，拉力只有在较小的拉力值时由突出驱动，当拉力足够大时由收缩取代。这使得力-速度关系的凹凸结构更为复杂；特别是，突出和收缩之间的竞争可在生物学相关范围内产生负活动。该模型说明了力产生机构根据外力偶极子结构的变化进行主动调整。在互补主动机制之间切换的可能性意味着，如有必要，“推动者”可以取代“推动者”，反之亦然。
Eukaryotic cells possess motility mechanisms allowing them not only to self-propel but also to exert forces on obstacles (to push) and to carry cargoes (to pull). To study the inherent asymmetry between active pushing and pulling we model a crawling acto-myosin cell extract as a one-dimensional layer of active gel subjected to external forces. We show that pushing is controlled by protrusion and that the macroscopic signature of the protrusion dominated motility mechanism is concavity of the force-velocity relation. In contrast, pulling is driven by protrusion only at small values of the pulling force and it is replaced by contraction when the pulling force is sufficiently large. This leads to more complex convex-concave structure of the force-velocity relation; in particular, competition between protrusion and contraction can produce negative mobility in a biologically relevant range. The model illustrates active readjustment of the force generating machinery in response to changes in the dipole structure of external forces. The possibility of switching between complementary active mechanisms implies that if necessary "pushers" can replace "pullers" and vice versa.
DOI：
10.1146/annurev.cellbio.011209.122036
发表时间：
2010
影响因子：
11.3
作者：
Gardel ML;Schneider IC;Aratyn-Schaus Y;Waterman CM
通讯作者：
Waterman CM