Jannie Karry M, Ellerbroek Shawn M, Zhou Dennis W, Chen Sophia, Crompton David J, García Andrés J, DeMali Kris A
*Department of Biochemistry, University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, IA 52242, U.S.A.
†Woodruff School of Mechanical Engineering, Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30332, U.S.A.
Biochem J. 2015 Feb 1;465(3):383-93. doi: 10.1042/BJ20140872.
Vinculin binding to actin filaments is thought to be critical for force transduction within a cell, but direct experimental evidence to support this conclusion has been limited. In the present study, we found mutation (R1049E) of the vinculin tail impairs its ability to bind F-actin, stimulate actin polymerization, and bundle F-actin in vitro. Further, mutant (R1049E) vinculin expressing cells are altered in cell migration, which is accompanied by changes in cell adhesion, cell spreading and cell generation of traction forces, providing direct evidence for the critical role of vinculin in mechanotransduction at adhesion sites. Lastly, we discuss the viability of models detailing the F-actin-binding surface on vinculin in the context of our mutational analysis.
纽蛋白与肌动蛋白丝的结合被认为对细胞内的力转导至关重要，但支持这一结论的直接实验证据一直有限。在本研究中，我们发现纽蛋白尾部的突变（R1049E）损害了其在体外结合F-肌动蛋白、刺激肌动蛋白聚合以及使F-肌动蛋白成束的能力。此外，表达突变型（R1049E）纽蛋白的细胞在细胞迁移方面发生改变，这伴随着细胞黏附、细胞铺展和细胞产生牵引力的变化，为纽蛋白在黏附位点的机械转导中的关键作用提供了直接证据。最后，我们在突变分析的背景下讨论了详细描述纽蛋白上F-肌动蛋白结合表面的模型的可行性。
