Mechanobiology & Soft Matter Group, Laboratoire Interfaces et Fluides Complexes, CIRMAP, Faculté des Sciences, Université de Mons, 20, place du Parc, B-7000 Mons, Belgium.
Nat Commun. 2012 Feb 14;3:671. doi: 10.1038/ncomms1668.
Growing evidence suggests that cytoplasmic actin filaments are essential factors in the modulation of nuclear shape and function. However, the mechanistic understanding of the internal orchestration between cell and nuclear shape is still lacking. Here we show that orientation and deformation of the nucleus are regulated by lateral compressive forces driven by tension in central actomyosin fibres. By using a combination of micro-manipulation tools, our study reveals that tension in central stress fibres is gradually generated by anisotropic force contraction dipoles, which expand as the cell elongates and spreads. Our findings indicate that large-scale cell shape changes induce a drastic condensation of chromatin and dramatically affect cell proliferation. On the basis of these findings, we propose a simple mechanical model that quantitatively accounts for our experimental data and provides a conceptual framework for the mechanistic coordination between cell and nuclear shape.
越来越多的证据表明细胞质肌动蛋白丝是调节核形状和功能的重要因素。然而，细胞和核形状之间的内在协调的机制理解仍然缺乏。在这里，我们表明核的取向和变形受由中心肌动球蛋白纤维张力驱动的侧向压缩力调节。通过使用微操作工具的组合，我们的研究表明，中心应力纤维中的张力是由各向异性力收缩偶极子逐渐产生的，随着细胞的伸长和扩散，这些偶极子会展开。我们的发现表明，大规模的细胞形状变化会引起染色质的剧烈浓缩，并显著影响细胞增殖。基于这些发现，我们提出了一个简单的力学模型，该模型定量地解释了我们的实验数据，并为细胞和核形状之间的机械协调提供了一个概念框架。
