Université P. et M. Curie/CNRS UMR, Paris, France.
Cell. 2011 Feb 4;144(3):402-13. doi: 10.1016/j.cell.2010.12.031.
The functions of caveolae, the characteristic plasma membrane invaginations, remain debated. Their abundance in cells experiencing mechanical stress led us to investigate their role in membrane-mediated mechanical response. Acute mechanical stress induced by osmotic swelling or by uniaxial stretching results in a rapid disappearance of caveolae, in a reduced caveolin/Cavin1 interaction, and in an increase of free caveolins at the plasma membrane. Tether-pulling force measurements in cells and in plasma membrane spheres demonstrate that caveola flattening and disassembly is the primary actin- and ATP-independent cell response that buffers membrane tension surges during mechanical stress. Conversely, stress release leads to complete caveola reassembly in an actin- and ATP-dependent process. The absence of a functional caveola reservoir in myotubes from muscular dystrophic patients enhanced membrane fragility under mechanical stress. Our findings support a new role for caveolae as a physiological membrane reservoir that quickly accommodates sudden and acute mechanical stresses.
小窝的功能，即特征性的质膜内陷，仍然存在争议。它们在经历机械应激的细胞中丰富，这促使我们研究它们在膜介导的机械反应中的作用。渗透压膨胀或单轴拉伸引起的急性机械应激导致小窝迅速消失，小窝蛋白/ Cavin1 相互作用减少，游离小窝蛋白在质膜上增加。细胞和质膜球体中的系绳拉力测量表明，小窝扁平化和解体是主要的肌动蛋白和 ATP 非依赖性细胞反应，可在机械应激期间缓冲膜张力激增。相反，在肌动蛋白和 ATP 依赖性过程中，应力释放导致小窝完全重新组装。来自肌肉营养不良患者的肌管中缺乏功能性小窝库，增强了它们在机械应激下的膜脆弱性。我们的发现支持小窝作为一种生理膜库的新作用，该膜库可快速适应突然和急性机械应激。
