Lemière Joël, Carvalho Kevin, Sykes Cécile
Institut Curie, Centre de Recherche, Paris, France; CNRS, UMR168, Paris, France; UPMC Univ Paris 06, UMR 168, Paris, France; Univ. Paris Diderot, Sorbonne Paris Cité, Paris, France; Current address: Department of Molecular Biophysics and Biochemistry, Nanobiology Institute, Yale University, New Haven, CT, USA.
Institut Curie, Centre de Recherche, Paris, France; CNRS, UMR168, Paris, France; UPMC Univ Paris 06, UMR 168, Paris, France; Univ. Paris Diderot, Sorbonne Paris Cité, Paris, France.
Methods Cell Biol. 2015;128:271-85. doi: 10.1016/bs.mcb.2015.01.013. Epub 2015 Apr 8.
Cells move and change shape by dynamically reorganizing their cytoskeleton next to the plasma membrane. In particular, actin assembly generates forces and stresses that deform the cell membrane. Cell-sized liposomes are designed to mimic this function. The activation of actin polymerization at their membrane is able to push the membrane forward, thus reproducing the mechanism of lamellipodium extension at the cell front. Moreover, the cell cortex, a submicrometer-thick actin shell right beneath the cell membrane can be reproduced; it contributes to cell tension with the action of molecular motors. We will describe experimental methods to prepare liposomes that mimic the inside geometry of a cell, and that reproduce actin-based propulsion of the liposome using an outside geometry. Such systems allow to study how actin-related proteins control and affect actin cortex assembly and can produce forces that drive cell shape changes.
细胞通过在质膜附近动态重组其细胞骨架来移动和改变形状。特别是，肌动蛋白组装产生使细胞膜变形的力和应力。细胞大小的脂质体旨在模拟这种功能。其膜上肌动蛋白聚合的激活能够推动膜向前，从而重现细胞前端片状伪足延伸的机制。此外，细胞膜下方亚微米厚的肌动蛋白壳层即细胞皮层也能够被重现；分子马达的作用使其对细胞张力有贡献。我们将描述制备模拟细胞内部几何结构以及利用外部几何结构重现基于肌动蛋白的脂质体推进的脂质体的实验方法。此类系统有助于研究肌动蛋白相关蛋白如何控制和影响肌动蛋白皮层组装，以及如何产生驱动细胞形状变化的力。
