Chapter 19 Mechanical Response of Cytoskeletal Networks

Department of Physics and Institute for Biophysical Dynamics, University of Chicago, Illinois 60637, USA.
Methods in cell biology (Impact Factor: 1.42). 02/2008; 89:487-519. DOI: 10.1016/S0091-679X(08)00619-5
Source: PubMed


The cellular cytoskeleton is a dynamic network of filamentous proteins, consisting of filamentous actin (F-actin), microtubules, and intermediate filaments. However, these networks are not simple linear, elastic solids; they can exhibit highly nonlinear elasticity and a thermal dynamics driven by ATP-dependent processes. To build quantitative mechanical models describing complex cellular behaviors, it is necessary to understand the underlying physical principles that regulate force transmission and dynamics within these networks. In this chapter, we review our current understanding of the physics of networks of cytoskeletal proteins formed in vitro. We introduce rheology, the technique used to measure mechanical response. We discuss our current understanding of the mechanical response of F-actin networks, and how the biophysical properties of F-actin and actin cross-linking proteins can dramatically impact the network mechanical response. We discuss how incorporating dynamic and rigid microtubules into F-actin networks can affect the contours of growing microtubules and composite network rigidity. Finally, we discuss the mechanical behaviors of intermediate filaments.

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Available from: Margaret L Gardel, Aug 15, 2014
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    • "The molecular nature of the contribution of tubulin to cell nanomechanics has been investigated in detail (Gardel et al. 2008). So far, the microtubule network is supposed to represent a compressive load-bearing component that counteracts the tensile forces generated by the cortical actimyosin web (Ingber 2003). "
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    ABSTRACT: The mechanical characteristics of endothelial cells reveal four distinct compartments, namely glycocalyx, cell cortex, cytoplasm and nucleus. There is accumulating evidence that endothelial nanomechanics of these individual compartments control vascular physiology. Depending on protein composition, filament formation and interaction with cross-linker proteins, these four compartments determine endothelial stiffness. Structural organization and mechanical properties directly influence physiological processes such as endothelial barrier function, nitric oxide release and gene expression. This review will focus on endothelial nanomechanics and its impact on vascular function.
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    • "Cytoskeleton is required for many biological processes, such as embryonic morphogenesis, immune surveillance, tissue repair, and regeneration. Aberrant regulation of cytoskeleton dynamics drives progression of cancer invasion and metastasis [1, 2]. Cancer cell metastasis is a multistage process involving invasion into surrounding tissue, intravasation, transit in the blood or lymph, extravasation, and growth at a new site. "
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    • "First, it is proposed to be an important component of sensing mechanisms, which translate the mechanical cues into biochemical signals [3], [4]. Second, the cytoskeleton is a stress-bearing structure that maintains cellular integrity and morphology and it serves as an actuator through adaption of its architecture [5], [6]. Due to these important properties, particular emphasis in cellular biomechanics has been given to the acto-myosin system [2], [7]. "
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