Integrin activation and internalization mediated by extracellular matrix elasticity: a biomechanical model.
Cells sense and respond to the elasticity of extracellular matrix (ECM) via integrin-mediated adhesion. As a class of well-documented mechanosenors in cells, integrins switch among inactive, bound, and dissociated states, depending upon the variation of forces acting on them. However, it remains unclear how the ECM elasticity directs and affects the states of integrins and, in turn, their cellular functions. On the basis of our recent experiments, a biomechanical model is proposed to reveal the role of ECM elasticity in the state-switching of integrins. It is demonstrated that a soft ECM can increase the activation level of integrins while a stiff ECM has a tendency to prevent the dissociation and internalization of bound integrins. In addition, it is found that more stable focal adhesions can form on stiffer and thinner ECMs. The theoretical results agree well with relevant experiments and shed light on the ECM elasticity-sensing mechanisms of cells.
Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China.
Guang-Kui
GK
Xu
Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China.
Chun
C
Yang
Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China.
Jing
J
Du
Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China. Electronic address: fengxq@tsinghua.edu.cn.
Xi-Qiao
XQ
Feng
D001696:Biomechanical Phenomena; D002448:Cell Adhesion; D002462:Cell Membrane; D004548:Elasticity; D005109:Extracellular Matrix / Q000502:physiology*; D022001:Focal Adhesions / Q000737:chemistry; D006801:Humans; D016023:Integrins / Q000737:chemistry*; D008954:Models, Biological; D033081:Shear Strength
D016023:Integrins
Cell adhesion; Elasticity; Extracellular matrix; Integrin activation; Integrin internalization