Shape oscillations of non-adhering fibroblast cells
Shape oscillations of non-adhering fibroblast cells
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DOI：
10.1088/1478-3975/4/4/004
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发表时间：
2007-12-01
期刊：
影响因子：
2
通讯作者：
Pullarkat, P.
中科院分区：
文献类型：
--
作者：
Salbreux, G.;Joanny, J. F.;Pullarkat, P.
我们证明，3T3 成纤维细胞在细胞与基质粘附丧失后可以表现出周期性形状振荡。振荡行为可以以恒定频率持续数小时，并且可以使用化学试剂关闭和打开。我们发现振荡频率随着肌动球蛋白收缩性的增加而增加。当细胞外钙耗尽或引入钙通道阻滞剂时，振荡也会停止。我们提出了基于皮质肌动蛋白层不稳定性的振荡的理论描述。使用活性凝胶的流体动力学理论描述皮质肌动蛋白层。我们假设钙通过机械门控通道进入细胞，并且钙密度的增加会增加皮质层中的肌动球蛋白的收缩性。该理论提供了肌动蛋白皮质层的稳定性图，显示了振荡不稳定性，并给出了振荡周期的良好描述。我们还讨论了这些振荡与微管解聚后观察到的其他振荡以及气泡形成之间的联系。
We demonstrate that 3T3 fibroblast cells can exhibit periodic shape oscillations following a loss of cell-substrate adhesion. The oscillatory behavior can last many hours at a constant frequency, and can be switched off and on using chemical agents. We show that the oscillation frequency increases with increasing acto-myosin contractility. The oscillations also cease when extracellular calcium is depleted or when a blocker of calcium channels is introduced. We propose a theoretical description of the oscillations based on an instability of the cortical actin layer. The cortical actin layer is described using the hydrodynamic theory of active gels. We assume that calcium enters the cell via mechanically gated channels and that an increase of the calcium density increases the acto-myosin contractility in the cortical layer. The theory provides a stability diagram for the actin cortical layer showing an oscillatory instability and gives a good description of the oscillation period. We also discuss the connections between these oscillations and other oscillations observed after depolymerization of the microtubules and with the formation of blebs.