Almeida Filipe V, Walko Gernot, McMillan James R, McGrath John A, Wiche Gerhard, Barber Asa H, Connelly John T
School of Engineering and Materials Science, Queen Mary, University of London, London, E1 4NS UK Centre for Cell Biology and Cutaneous Research, Barts and the London School of Medicine and Dentistry, Queen Mary, University of London, London, E1 2AT UK.
Centre for Stem Cells and Regenerative Medicine, King's College London, London, SE1 9RT UK.
J Cell Sci. 2015 Dec 15;128(24):4475-86. doi: 10.1242/jcs.173435. Epub 2015 Nov 2.
The transmission of mechanical forces to the nucleus is important for intracellular positioning, mitosis and cell motility, yet the contribution of specific components of the cytoskeleton to nuclear mechanotransduction remains unclear. In this study, we examine how crosstalk between the cytolinker plectin and F-actin controls keratin network organisation and the 3D nuclear morphology of keratinocytes. Using micro-patterned surfaces to precisely manipulate cell shape, we find that cell adhesion and spreading regulate the size and shape of the nucleus. Disruption of the keratin cytoskeleton through loss of plectin facilitated greater nuclear deformation, which depended on acto-myosin contractility. Nuclear morphology did not depend on direct linkage of the keratin cytoskeleton with the nuclear membrane, rather loss of plectin reduced keratin filament density around the nucleus. We further demonstrate that keratinocytes have abnormal nuclear morphologies in the epidermis of plectin-deficient, epidermolysis bullosa simplex patients. Taken together, our data demonstrate that plectin is an essential regulator of nuclear morphology in vitro and in vivo and protects the nucleus from mechanical deformation.
机械力向细胞核的传递对于细胞内定位、有丝分裂和细胞运动很重要，然而细胞骨架的特定成分对核机械转导的贡献仍不清楚。在本研究中，我们研究了细胞连接蛋白网蛋白与F-肌动蛋白之间的相互作用如何控制角质形成细胞的角蛋白网络组织和三维核形态。使用微图案化表面精确操纵细胞形状，我们发现细胞粘附和铺展调节细胞核的大小和形状。通过网蛋白缺失破坏角蛋白细胞骨架促进了更大程度的核变形，这取决于肌动蛋白-肌球蛋白收缩性。核形态并不依赖于角蛋白细胞骨架与核膜的直接连接，相反，网蛋白的缺失降低了细胞核周围角蛋白丝的密度。我们进一步证明，在网蛋白缺陷型单纯性大疱性表皮松解症患者的表皮中，角质形成细胞具有异常的核形态。综上所述，我们的数据表明，网蛋白在体外和体内都是核形态的重要调节因子，并保护细胞核免受机械变形。
