Multidimensional traction force microscopy reveals out-of-plane rotational moments about focal adhesions

• DOI: 10.1073/pnas.1207997110
• Publication Date: 2013-01-01T03:18:40Z
• Authors: Wesley R. Legant; Colin K. Choi; Jordan S. Miller; Lin Shao; Liang Gao; Eric Betzig; Christopher S. Chen
• Keywords: 0301 basic medicine; Focal Adhesions; Rotation; Finite Element Analysis; Green Fluorescent Proteins; Fibroblasts; Mechanotransduction, Cellular; Models, Biological; Biophysical Phenomena; Recombinant Proteins; Mice; 03 medical and health sciences; Microscopy, Fluorescence; Animals

Recent methods have revealed that cells on planar substrates exert both shear (in-plane) and normal (out-of-plane) tractions against the extracellular matrix (ECM). However, location origin of with respect to adhesive cytoskeletal elements not been elucidated. We developed a high-spatiotemporal-resolution, multidimensional (2.5D) traction force microscopy measure model full 3D nature cellular forces 2D surfaces. show are centered under elongated focal adhesions whereas upward downward detected distal (toward cell edge) proximal body) ends adhesions, respectively. Together, these produce significant rotational moments about in protruding retracting peripheral regions. Temporal 2.5D analysis migrating spreading shows highly dynamic, propagating outward leading edge cell. Finally, we finite element examine how could be generated thin lamella. Our suggests can largely via lag transfer underlying ECM from actomyosin contractility applied at intracellular surface rigid adhesion thickness. data demonstrate probe previously unappreciated stress profile associated highlight importance new approaches characterize forces.