51
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Chengappa P, Sao K, Jones TM, Petrie RJ. Intracellular Pressure: A Driver of Cell Morphology and Movement. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2018; 337:185-211. [PMID: 29551161 DOI: 10.1016/bs.ircmb.2017.12.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Intracellular pressure, generated by actomyosin contractility and the directional flow of water across the plasma membrane, can rapidly reprogram cell shape and behavior. Recent work demonstrates that cells can generate intracellular pressure with a range spanning at least two orders of magnitude; significantly, pressure is implicated as an important regulator of cell dynamics, such as cell division and migration. Changes to intracellular pressure can dictate the mechanisms by which single human cells move through three-dimensional environments. In this review, we chronicle the classic as well as recent evidence demonstrating how intracellular pressure is generated and maintained in metazoan cells. Furthermore, we highlight how this potentially ubiquitous physical characteristic is emerging as an important driver of cell morphology and behavior.
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Affiliation(s)
| | - Kimheak Sao
- Drexel University, Philadelphia, PA, United States
| | - Tia M Jones
- Drexel University, Philadelphia, PA, United States
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52
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Sugimoto W, Itoh K, Mitsui Y, Ebata T, Fujita H, Hirata H, Kawauchi K. Substrate rigidity-dependent positive feedback regulation between YAP and ROCK2. Cell Adh Migr 2018; 12:101-108. [PMID: 28686514 DOI: 10.1080/19336918.2017.1338233] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Extracellular matrix (ECM) stiffness influences gene expression, leading to modulation of various cellular functions. While ROCK2 regulates actomyosin activity as well as cell migration and proliferation, expression of ROCK2 is increased in response to stiffening ECM. However, the mechanism underlying rigidity-dependent ROCK2 expression remains elusive. Here, we show that YAP, a mechanically regulated transcription coactivator, upregulates ROCK2 expression in an ECM rigidity-dependent manner. YAP interacted with the ROCK2 promoter region in an actomyosin activity-dependent manner. Knockdown of YAP decreased ROCK2 expression while activity of the ROCK2 promoter was upregulated by expressing constitutively active YAP. Furthermore, we found that ROCK2 expression promotes transcriptional activation by YAP. Our results reveal a novel positive feedback loop between YAP and ROCK2, which is modulated by ECM stiffness.
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Affiliation(s)
- Wataru Sugimoto
- a Frontiers of Innovative Research in Science and Technology , Konan University , Kobe, Hyogo , Japan
| | - Katsuhiko Itoh
- a Frontiers of Innovative Research in Science and Technology , Konan University , Kobe, Hyogo , Japan
| | - Yasumasa Mitsui
- a Frontiers of Innovative Research in Science and Technology , Konan University , Kobe, Hyogo , Japan
| | - Takahiro Ebata
- a Frontiers of Innovative Research in Science and Technology , Konan University , Kobe, Hyogo , Japan
| | - Hideaki Fujita
- b Laboratory for Comprehensive Bioimaging , Riken Qbic , Osaka , Japan.,c Waseda Bioscience Research Institute in Singapore , Singapore , Republic of Singapore
| | - Hiroaki Hirata
- d Mechanobiology Laboratory , Nagoya University Graduate School of Medicine , Nagoya, Aichi , Japan
| | - Keiko Kawauchi
- a Frontiers of Innovative Research in Science and Technology , Konan University , Kobe, Hyogo , Japan.,e Department of Molecular Oncology , Institute for Advanced Medical Sciences, Nippon Medical School , Kawasaki, Kanagawa , Japan
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53
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Sun X, Hourwitz MJ, Baker EM, Schmidt BUS, Losert W, Fourkas JT. Replication of biocompatible, nanotopographic surfaces. Sci Rep 2018; 8:564. [PMID: 29330498 PMCID: PMC5766624 DOI: 10.1038/s41598-017-19008-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Accepted: 12/20/2017] [Indexed: 01/16/2023] Open
Abstract
The ability of cells to sense and respond to nanotopography is being implicated as a key element in many physiological processes such as cell differentiation, immune response, and wound healing, as well as in pathologies such as cancer metastasis. To understand how nanotopography affects cellular behaviors, new techniques are required for the mass production of biocompatible, rigid nanotopographic surfaces. Here we introduce a method for the rapid and reproducible production of biocompatible, rigid, acrylic nanotopographic surfaces, and for the functionalization of the surfaces with adhesion-promoting molecules for cell experiments. The replica surfaces exhibit high optical transparency, which is advantageous for high-resolution, live-cell imaging. As a representative application, we demonstrate that epithelial cells form focal adhesions on surfaces composed of nanoscale ridges and grooves, and that the focal adhesions prefer to localize on the nanoridges. We further demonstrate that both F-actin and microtubules align along the nanoridges, but only F-actin aligns along the nanogrooves. The mass production of nanotopographic surfaces opens the door to the investigation of the effect of physical cues on the spatial distribution and the dynamics of intracellular proteins, and to the study of the mechanism of mechanosensing in processes such as cell migration, phagocytosis, division, and differentiation.
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Affiliation(s)
- Xiaoyu Sun
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD, 20742, USA
| | - Matt J Hourwitz
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD, 20742, USA
| | - Eleni M Baker
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD, 20742, USA
| | - B U Sebastian Schmidt
- Institute for Physical Science and Technology, University of Maryland, College Park, MD, 20742, USA
| | - Wolfgang Losert
- Institute for Physical Science and Technology, University of Maryland, College Park, MD, 20742, USA. .,Department of Physics, University of Maryland, College Park, MD, 20742, USA. .,Maryland NanoCenter, University of Maryland, College Park, MD, 20742, USA.
| | - John T Fourkas
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD, 20742, USA. .,Institute for Physical Science and Technology, University of Maryland, College Park, MD, 20742, USA. .,Center for Nanophysics and Advanced Materials, University of Maryland, College Park, MD, 20742, USA. .,Maryland NanoCenter, University of Maryland, College Park, MD, 20742, USA.
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54
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Ishihara S, Inman DR, Li WJ, Ponik SM, Keely PJ. Mechano-Signal Transduction in Mesenchymal Stem Cells Induces Prosaposin Secretion to Drive the Proliferation of Breast Cancer Cells. Cancer Res 2017; 77:6179-6189. [PMID: 28972074 DOI: 10.1158/0008-5472.can-17-0569] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 06/27/2017] [Accepted: 09/25/2017] [Indexed: 01/15/2023]
Abstract
In response to chemical stimuli from cancer cells, mesenchymal stem cells (MSC) can differentiate into cancer-associated fibroblasts (CAF) and promote tumor progression. How mechanical stimuli such as stiffness of the extracellular matrix (ECM) contribute to MSC phenotype in cancer remains poorly understood. Here, we show that ECM stiffness leads to mechano-signal transduction in MSC, which promotes mammary tumor growth in part through secretion of the signaling protein prosaposin. On a stiff matrix, MSC cultured with conditioned media from mammary cancer cells expressed increased levels of α-smooth muscle actin, a marker of CAF, compared with MSC cultured on a soft matrix. By contrast, MSC cultured on a stiff matrix secreted prosaposin that promoted proliferation and survival of mammary carcinoma cells but inhibited metastasis. Our findings suggest that in addition to chemical stimuli, increased stiffness of the ECM in the tumor microenvironment induces differentiation of MSC to CAF, triggering enhanced proliferation and survival of mammary cancer cells. Cancer Res; 77(22); 6179-89. ©2017 AACR.
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Affiliation(s)
- Seiichiro Ishihara
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, Wisconsin.
| | - David R Inman
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Wan-Ju Li
- Departments of Orthopedics and Rehabilitation, and Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin
| | - Suzanne M Ponik
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Patricia J Keely
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, Wisconsin
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55
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Hörning M, Nakahata M, Linke P, Yamamoto A, Veschgini M, Kaufmann S, Takashima Y, Harada A, Tanaka M. Dynamic Mechano-Regulation of Myoblast Cells on Supramolecular Hydrogels Cross-Linked by Reversible Host-Guest Interactions. Sci Rep 2017; 7:7660. [PMID: 28794475 PMCID: PMC5550483 DOI: 10.1038/s41598-017-07934-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 07/05/2017] [Indexed: 01/09/2023] Open
Abstract
A new class of supramolecular hydrogels, cross-linked by host-guest interactions between β-cyclodextrin (βCD) and adamantane, were designed for the dynamic regulation of cell-substrate interactions. The initial substrate elasticity can be optimized by selecting the molar fraction of host- and guest monomers for the target cells. Moreover, owing to the reversible nature of host-guest interactions, the magnitude of softening and stiffening of the substrate can be modulated by varying the concentrations of free, competing host molecules (βCD) in solutions. By changing the substrate elasticity at a desired time point, it is possible to switch the micromechanical environments of cells. We demonstrated that the Young's modulus of our "host-guest gels", 4-11 kPa, lies in an optimal range not only for static (ex situ) but also for dynamic (in situ) regulation of cell morphology and cytoskeletal ordering of myoblasts. Compared to other stimulus-responsive materials that can either change the elasticity only in one direction or rely on less biocompatible stimuli such as UV light and temperature change, our supramolecular hydrogel enables to reversibly apply mechanical cues to various cell types in vitro without interfering cell viability.
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Affiliation(s)
- Marcel Hörning
- Institute for Integrated Cell-Material Science (WPI iCeMS), Kyoto University, Kyoto, 606-8501, Japan
- Institute of Biomaterials and Biomolecular Systems (IBBS), University of Stuttgart, 70569, Stuttgart, Germany
| | - Masaki Nakahata
- Project Research Center for Fundamental Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka, 560-0043, Japan
- Division of Chemical Engineering, Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka, 560-8531, Japan
| | - Philipp Linke
- Physical Chemistry of Biosystems, University of Heidelberg, D69120, Heidelberg, Germany
| | - Akihisa Yamamoto
- Institute for Integrated Cell-Material Science (WPI iCeMS), Kyoto University, Kyoto, 606-8501, Japan
| | - Mariam Veschgini
- Physical Chemistry of Biosystems, University of Heidelberg, D69120, Heidelberg, Germany
| | - Stefan Kaufmann
- Physical Chemistry of Biosystems, University of Heidelberg, D69120, Heidelberg, Germany
| | - Yoshinori Takashima
- Department of Macromolecular Science, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka, 560-0043, Japan
| | - Akira Harada
- Project Research Center for Fundamental Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka, 560-0043, Japan.
| | - Motomu Tanaka
- Institute for Integrated Cell-Material Science (WPI iCeMS), Kyoto University, Kyoto, 606-8501, Japan.
- Physical Chemistry of Biosystems, University of Heidelberg, D69120, Heidelberg, Germany.
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56
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Könnig D, Herrera A, Duda GN, Petersen A. Mechanosensation across borders: fibroblasts inside a macroporous scaffold sense and respond to the mechanical environment beyond the scaffold walls. J Tissue Eng Regen Med 2017; 12:265-275. [PMID: 28084698 DOI: 10.1002/term.2410] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 12/09/2016] [Accepted: 01/10/2017] [Indexed: 12/17/2022]
Abstract
In tissue defects, cells face distinct mechanical boundary conditions, but how this influences early stages of tissue regeneration remains largely unknown. Biomaterials are used to fill defects but also to provide specific mechanical or geometrical signals. However, they might at the same time shield mechanical information from surrounding tissues that is relevant for tissue functionalisation. This study investigated how fibroblasts in a soft macroporous biomaterial scaffold respond to distinct mechanical environments while they form microtissues. Different boundary stiffnesses counteracting scaffold contraction were provided via a newly developed in vitro setup. Online monitoring over 14 days revealed 3.0 times lower microtissue contraction but 1.6 times higher contraction force for high vs. low stiffness. This difference was significant already after 48 h, a very early stage of microtissue growth. The microtissue's mechanical and geometrical adaptation indicated a collective cellular behaviour and mechanical communication across scaffold pore walls. Surprisingly, the stiffness of the environment influenced cell behaviour even inside macroporous scaffolds where direct cell-cell contacts are hindered. Mechanical communication between cells via traction forces is essential for tissue adaptation to the environment and should not be blocked by rigid biomaterials. Copyright © 2017 John Wiley & Sons, Ltd.
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Affiliation(s)
- D Könnig
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Berlin-Brandenburg School for Regenerative Therapies, Berlin, Germany
| | - A Herrera
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Berlin-Brandenburg School for Regenerative Therapies, Berlin, Germany
| | - G N Duda
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Berlin-Brandenburg School for Regenerative Therapies, Berlin, Germany.,Center for Musculoskeletal Surgery - Universitätsmedizin Berlin, Berlin, Germany.,Berlin-Brandenburg Center for Regenerative Therapies, Berlin, Germany
| | - A Petersen
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Center for Musculoskeletal Surgery - Universitätsmedizin Berlin, Berlin, Germany.,Berlin-Brandenburg Center for Regenerative Therapies, Berlin, Germany
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57
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Šmít D, Fouquet C, Pincet F, Zapotocky M, Trembleau A. Axon tension regulates fasciculation/defasciculation through the control of axon shaft zippering. eLife 2017; 6:19907. [PMID: 28422009 PMCID: PMC5478281 DOI: 10.7554/elife.19907] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 04/04/2017] [Indexed: 01/16/2023] Open
Abstract
While axon fasciculation plays a key role in the development of neural networks, very little is known about its dynamics and the underlying biophysical mechanisms. In a model system composed of neurons grown ex vivo from explants of embryonic mouse olfactory epithelia, we observed that axons dynamically interact with each other through their shafts, leading to zippering and unzippering behavior that regulates their fasciculation. Taking advantage of this new preparation suitable for studying such interactions, we carried out a detailed biophysical analysis of zippering, occurring either spontaneously or induced by micromanipulations and pharmacological treatments. We show that zippering arises from the competition of axon-axon adhesion and mechanical tension in the axons, and provide the first quantification of the force of axon-axon adhesion. Furthermore, we introduce a biophysical model of the zippering dynamics, and we quantitatively relate the individual zipper properties to global characteristics of the developing axon network. Our study uncovers a new role of mechanical tension in neural development: the regulation of axon fasciculation.
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Affiliation(s)
- Daniel Šmít
- Institute of Physiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Coralie Fouquet
- Neuroscience Paris Seine - Institute of Biology Paris Seine, Sorbonne Université, UPMC Univ Paris 06, INSERM, CNRS, Paris, France
| | - Frédéric Pincet
- Laboratoire de Physique Statistique, Ecole Normale Superieure, PSL Research University, Paris, France
| | - Martin Zapotocky
- Institute of Physiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Alain Trembleau
- Neuroscience Paris Seine - Institute of Biology Paris Seine, Sorbonne Université, UPMC Univ Paris 06, INSERM, CNRS, Paris, France
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58
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Hickey R, Pelling AE. The rotation of mouse myoblast nuclei is dependent on substrate elasticity. Cytoskeleton (Hoboken) 2017; 74:184-194. [PMID: 28236372 DOI: 10.1002/cm.21357] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Revised: 02/15/2017] [Accepted: 02/21/2017] [Indexed: 11/09/2022]
Abstract
The complex interplay of biochemical signaling and mechanical traction forces regulate the position of cellular nuclei. Although the phenomenon of nuclear rotation has been observed for many years, the influence of substrate elasticity was unknown. We discovered another layer of complexity to this phenomenon: nuclear rotation is dependent on substrate elasticity. Nuclear rotation is drastically reduced on physiologically relevant stiffnesses. Here, we studied nuclear rotation in mouse C2C12 myoblasts cultured on soft substrates designed to mimic resting tissue (∼26 kPa) and on hard glass substrates. We examined the roles of the actin and microtubule cytoskeleton on the presence and dynamics of nuclear rotation in these two different microenvironments. We demonstrated the clear dependence of nuclear rotation dynamics on matrix stiffness. These results will have important implications for the design of future studies of nuclear rotation and our understanding of the phenomenon as a whole. Unnaturally, hard substrates do not only fail to mimic the in vivo microenvironment, but can also induce cellular processes that would not normally occur in the natural cellular environment.
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Affiliation(s)
- Ryan Hickey
- Centre for Interdisciplinary NanoPhysics, Department of Physics, University of Ottawa, MacDonald Hall, 150 Louis Pasteur, Ottawa, ON, K1N5N5, Canada
| | - Andrew E Pelling
- Centre for Interdisciplinary NanoPhysics, Department of Physics, University of Ottawa, MacDonald Hall, 150 Louis Pasteur, Ottawa, ON, K1N5N5, Canada.,Department of Biology, University of Ottawa, Gendron Hall, 30 Marie Curie, Ottawa, ON, K1N5N5, Canada.,Institute for Science Society and Policy, Simard Hall, 60 University, University of Ottawa, Ottawa, ON, K1N5N5, Canada.,SymbioticA, School of Anatomy, Physiology and Human Biology, University of Western Australia, Perth, WA, 6009
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59
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Center or periphery? Modeling the effects of focal adhesion placement during cell spreading. PLoS One 2017; 12:e0171430. [PMID: 28158263 PMCID: PMC5291721 DOI: 10.1371/journal.pone.0171430] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Accepted: 01/20/2017] [Indexed: 01/06/2023] Open
Abstract
Focal adhesions are often observed at the cell's periphery. We provide an explanation for this observation using a system-level mathematical model of a cell interacting with a two-dimensional substrate. The model describes the biological cell as a hypoelastic continuum material whose behavior is coupled to a deformable, linear elastic substrate via focal adhesions that are represented by collections of linear elastic attachments between the cell and the substrate. The evolution of the focal adhesions is coupled to local intracellular stresses which arise from mechanical cell-substrate interactions. Using this model we show that the cell has at least three mechanisms through which it can control its intracellular stresses: focal adhesion position, size, and attachment strength. We also propose that one reason why focal adhesions are typically located on the cell periphery instead of its center is because peripheral focal adhesions allow the cell to be more sensitive to changes in the microenvironment. This increased sensitivity is caused by the fact that peripherally located focal adhesions allow the cells to modulate its intracellular properties over a much larger portion of the cell area.
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60
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Substrate Stiffness Influences Doxorubicin-Induced p53 Activation via ROCK2 Expression. BIOMED RESEARCH INTERNATIONAL 2017; 2017:5158961. [PMID: 28191463 PMCID: PMC5278210 DOI: 10.1155/2017/5158961] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2016] [Revised: 12/03/2016] [Accepted: 12/12/2016] [Indexed: 01/15/2023]
Abstract
The physical properties of the extracellular matrix (ECM), such as stiffness, are involved in the determination of the characteristics of cancer cells, including chemotherapy sensitivity. Resistance to chemotherapy is often linked to dysfunction of tumor suppressor p53; however, it remains elusive whether the ECM microenvironment interferes with p53 activation in cancer cells. Here, we show that, in MCF-7 breast cancer cells, extracellular stiffness influences p53 activation induced by the antitumor drug doxorubicin. Cell growth inhibition by doxorubicin was increased in response to ECM rigidity in a p53-dependent manner. The expression of Rho-associated coiled coil-containing protein kinase (ROCK) 2, which induces the activation of myosin II, was significantly higher when cells were cultured on stiffer ECM substrates. Knockdown of ROCK2 expression or pharmacological inhibition of ROCK decreased doxorubicin-induced p53 activation. Our results suggest that a soft ECM causes downregulation of ROCK2 expression, which drives resistance to chemotherapy by repressing p53 activation.
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61
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Matrix mechanics controls FHL2 movement to the nucleus to activate p21 expression. Proc Natl Acad Sci U S A 2016; 113:E6813-E6822. [PMID: 27742790 DOI: 10.1073/pnas.1608210113] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Substrate rigidity affects many physiological processes through mechanochemical signals from focal adhesion (FA) complexes that subsequently modulate gene expression. We find that shuttling of the LIM domain (domain discovered in the proteins, Lin11, Isl-1, and Mec-3) protein four-and-a-half LIM domains 2 (FHL2) between FAs and the nucleus depends on matrix mechanics. In particular, on soft surfaces or after the loss of force, FHL2 moves from FAs into the nucleus and concentrates at RNA polymerase (Pol) II sites, where it acts as a transcriptional cofactor, causing an increase in p21 gene expression that will inhibit growth on soft surfaces. At the molecular level, shuttling requires a specific tyrosine in FHL2, as well as phosphorylation by active FA kinase (FAK). Thus, we suggest that FHL2 phosphorylation by FAK is a critical, mechanically dependent step in signaling from soft matrices to the nucleus to inhibit cell proliferation by increasing p21 expression.
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62
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Hirata H, Ku WC, Yip AK, Ursekar CP, Kawauchi K, Roy A, Guo AK, Vedula SRK, Harada I, Chiam KH, Ishihama Y, Lim CT, Sawada Y, Sokabe M. MEKK1-dependent phosphorylation of calponin-3 tunes cell contractility. J Cell Sci 2016; 129:3574-3582. [PMID: 27528401 DOI: 10.1242/jcs.189415] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 08/10/2016] [Indexed: 12/30/2022] Open
Abstract
MEKK1 (also known as MAP3K1), which plays a major role in MAPK signaling, has been implicated in mechanical processes in cells, such as migration. Here, we identify the actin-binding protein calponin-3 as a new MEKK1 substrate in the signaling that regulates actomyosin-based cellular contractility. MEKK1 colocalizes with calponin-3 at the actin cytoskeleton and phosphorylates it, leading to an increase in the cell-generated traction stress. MEKK1-mediated calponin-3 phosphorylation is attenuated by the inhibition of myosin II activity, the disruption of actin cytoskeletal integrity and adhesion to soft extracellular substrates, whereas it is enhanced upon cell stretching. Our results reveal the importance of the MEKK1-calponin-3 signaling pathway to cell contractility.
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Affiliation(s)
- Hiroaki Hirata
- Mechanobiology Institute, National University of Singapore, 117411 Singapore
| | - Wei-Chi Ku
- Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan
| | - Ai Kia Yip
- A*STAR Bioinformatics Institute, 138671 Singapore
| | | | - Keiko Kawauchi
- Mechanobiology Institute, National University of Singapore, 117411 Singapore
| | - Amrita Roy
- Mechanobiology Institute, National University of Singapore, 117411 Singapore
| | - Alvin Kunyao Guo
- Mechanobiology Institute, National University of Singapore, 117411 Singapore
| | | | - Ichiro Harada
- Locomotive Syndrome Research Institute, Nadogaya Hospital, Kashiwa 277-0032, Japan Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama 226-8501, Japan
| | - Keng-Hwee Chiam
- Mechanobiology Institute, National University of Singapore, 117411 Singapore A*STAR Bioinformatics Institute, 138671 Singapore
| | - Yasushi Ishihama
- Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan
| | - Chwee Teck Lim
- Mechanobiology Institute, National University of Singapore, 117411 Singapore Department of Biomedical Engineering, National University of Singapore, 117583 Singapore
| | - Yasuhiro Sawada
- Mechanobiology Institute, National University of Singapore, 117411 Singapore Locomotive Syndrome Research Institute, Nadogaya Hospital, Kashiwa 277-0032, Japan Department of Biological Sciences, National University of Singapore, 117543 Singapore
| | - Masahiro Sokabe
- Mechanobiology Institute, National University of Singapore, 117411 Singapore Mechanobiology Laboratory, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
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63
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Sia J, Yu P, Srivastava D, Li S. Effect of biophysical cues on reprogramming to cardiomyocytes. Biomaterials 2016; 103:1-11. [DOI: 10.1016/j.biomaterials.2016.06.034] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 06/06/2016] [Accepted: 06/15/2016] [Indexed: 01/12/2023]
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64
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Substrate Deformation Predicts Neuronal Growth Cone Advance. Biophys J 2016; 109:1358-71. [PMID: 26445437 DOI: 10.1016/j.bpj.2015.08.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 08/11/2015] [Accepted: 08/12/2015] [Indexed: 11/23/2022] Open
Abstract
Although pulling forces have been observed in axonal growth for several decades, their underlying mechanisms, absolute magnitudes, and exact roles are not well understood. In this study, using two different experimental approaches, we quantified retrograde traction force in Aplysia californica neuronal growth cones as they develop over time in response to a new adhesion substrate. In the first approach, we developed a novel method, to our knowledge, for measuring traction forces using an atomic force microscope (AFM) with a cantilever that was modified with an Aplysia cell adhesion molecule (apCAM)-coated microbead. In the second approach, we used force-calibrated glass microneedles coated with apCAM ligands to guide growth cone advance. The traction force exerted by the growth cone was measured by monitoring the microneedle deflection using an optical microscope. Both approaches showed that Aplysia growth cones can develop traction forces in the 10(0)-10(2) nN range during adhesion-mediated advance. Moreover, our results suggest that the level of traction force is directly correlated to the stiffness of the microneedle, which is consistent with a reinforcement mechanism previously observed in other cell types. Interestingly, the absolute level of traction force did not correlate with growth cone advance toward the adhesion site, but the amount of microneedle deflection did. In cases of adhesion-mediated growth cone advance, the mean needle deflection was 1.05 ± 0.07 μm. By contrast, the mean deflection was significantly lower (0.48 ± 0.06 μm) when the growth cones did not advance. Our data support a hypothesis that adhesion complexes, which can undergo micron-scale elastic deformation, regulate the coupling between the retrogradely flowing actin cytoskeleton and apCAM substrates, stimulating growth cone advance if sufficiently abundant.
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65
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Morita Y, Kawase N, Ju Y, Yamauchi T. Mesenchymal stem cell-induced 3D displacement field of cell-adhesion matrices with differing elasticities. J Mech Behav Biomed Mater 2016; 60:394-400. [DOI: 10.1016/j.jmbbm.2016.02.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 02/15/2016] [Accepted: 02/18/2016] [Indexed: 01/01/2023]
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66
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Fabrication of Elasticity-Tunable Gelatinous Gel for Mesenchymal Stem Cell Culture. Methods Mol Biol 2016. [PMID: 27236687 DOI: 10.1007/978-1-4939-3584-0_25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Surface elasticity or stiffness of an underlying substrate may regulate cellular functions such as adhesion, proliferation, signaling, differentiation, and migration. Recent studies have reported on the development of biomaterials to control stem cell fate determination via the stiffness of the culture substrates. In this chapter, we provide a detailed protocol for fabricating elasticity-tunable gelatinous hydrogels for stem cell culture with photo-induced or thermo-induced crosslinking of well-developed styrenated gelatin (StG). We also include the detailed application of gelatinous gel for mesenchymal stem cell (MSC) culture and sample collection for transcriptional and proteomic analysis.
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67
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Müller C, Pompe T. Distinct impacts of substrate elasticity and ligand affinity on traction force evolution. SOFT MATTER 2016; 12:272-280. [PMID: 26451588 DOI: 10.1039/c5sm01706h] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Cell adhesion is regulated by the mechanical characteristics of the cell environment. The influences of different parameters of the adhesive substrates are convoluted in the cell response leading to questions on the underlying mechanisms, like biochemical signaling on the level of adhesion molecules, or viscoelastic properties of substrates and cell. By a time-resolved analysis of traction force generation during early cell adhesion, we wanted to elucidate the contributions of substrate mechanics to the adhesion process, in particular the impact of substrate elasticity and the molecular friction of adhesion ligands on the substrate surface. Both parameters were independently adjusted by (i) an elastic polyacrylamide hydrogel of variable crosslinking degree and (ii) a thin polymer coating of the hydrogel surface controlling the affinity (and the correlated substrate-ligand friction) of the adhesion ligand fibronectin. Our analysis showed two sequential regimes of considerable force generation, whose occurrence was found to be independent of substrate properties. The first regime is characterized by spreading of the cell and a succeeding force increase. After spreading cells enter the second regime with saturated forces. Substrate elasticity and viscosity, namely hydrogel elasticity and ligand affinity, were both found to affect the kinetics and absolute levels of traction force quantities. A faster increase and a higher saturation level of traction forces were observed for a higher substrate stiffness and a higher ligand affinity. The results complement recent modeling approaches on the evolution of forces in cell spreading and contribute to a better understanding of the dynamics of cell adhesion on viscoelastic substrates.
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Affiliation(s)
- Christina Müller
- Faculty of Biosciences, Pharmacy and Psychology, Universität Leipzig, Johannisallee 21-23, 04103 Leipzig, Germany.
| | - Tilo Pompe
- Faculty of Biosciences, Pharmacy and Psychology, Universität Leipzig, Johannisallee 21-23, 04103 Leipzig, Germany.
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68
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Bidhendi AJ, Geitmann A. Relating the mechanics of the primary plant cell wall to morphogenesis. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:449-61. [PMID: 26689854 DOI: 10.1093/jxb/erv535] [Citation(s) in RCA: 119] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Regulation of the mechanical properties of the cell wall is a key parameter used by plants to control the growth behavior of individual cells and tissues. Modulation of the mechanical properties occurs through the control of the biochemical composition and the degree and nature of interlinking between cell wall polysaccharides. Preferentially oriented cellulose microfibrils restrict cellular expansive growth, but recent evidence suggests that this may not be the trigger for anisotropic growth. Instead, non-uniform softening through the modulation of pectin chemistry may be an initial step that precedes stress-induced stiffening of the wall through cellulose. Here we briefly review the major cell wall polysaccharides and their implication for plant cell wall mechanics that need to be considered in order to study the growth behavior of the primary plant cell wall.
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Affiliation(s)
- Amir J Bidhendi
- Institut de recherche en biologie végétale, Département de sciences biologiques, Université de Montréal, Montreal, Quebec H1X 2B2, Canada
| | - Anja Geitmann
- Institut de recherche en biologie végétale, Département de sciences biologiques, Université de Montréal, Montreal, Quebec H1X 2B2, Canada
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69
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Athamneh AIM, Suter DM. Quantifying mechanical force in axonal growth and guidance. Front Cell Neurosci 2015; 9:359. [PMID: 26441530 PMCID: PMC4584967 DOI: 10.3389/fncel.2015.00359] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 08/27/2015] [Indexed: 11/17/2022] Open
Abstract
Mechanical force plays a fundamental role in neuronal development, physiology, and regeneration. In particular, research has shown that force is involved in growth cone-mediated axonal growth and guidance as well as stretch-induced elongation when an organism increases in size after forming initial synaptic connections. However, much of the details about the exact role of force in these fundamental processes remain unknown. In this review, we highlight: (1) standing questions concerning the role of mechanical force in axonal growth and guidance; and (2) different experimental techniques used to quantify forces in axons and growth cones. We believe that satisfying answers to these questions will require quantitative information about the relationship between elongation, forces, cytoskeletal dynamics, axonal transport, signaling, substrate adhesion, and stiffness contributing to directional growth advance. Furthermore, we address why a wide range of force values have been reported in the literature, and what these values mean in the context of neuronal mechanics. We hope that this review will provide a guide for those interested in studying the role of force in development and regeneration of neuronal networks.
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Affiliation(s)
- Ahmad I M Athamneh
- Bindley Bioscience Center, Birck Nanotechnology Center, Department of Biological Sciences, Purdue University West Lafayette, IN, USA
| | - Daniel M Suter
- Bindley Bioscience Center, Birck Nanotechnology Center, Department of Biological Sciences, Purdue University West Lafayette, IN, USA
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70
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Activation of Yes-Associated Protein in Low-Grade Meningiomas Is Regulated by Merlin, Cell Density, and Extracellular Matrix Stiffness. J Neuropathol Exp Neurol 2015; 74:704-9. [PMID: 26049897 DOI: 10.1097/nen.0000000000000211] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The NF2 gene product Merlin is a protein containing ezrin, radixin, and moesin domains; it is a member of the 4.1 protein superfamily associated with the membrane cytoskeleton and also interacts with cell surface molecules. The mammalian Hippo cascade, a downstream signaling cascade of merlin, inactivates the Yes-associated protein (YAP). Yes-associated protein is activated by loss of the NF2 gene and functions as an oncogene in meningioma cells; however, the factors controlling YAP expression, phosphorylation, and subcellular localization in meningiomas have not been fully elucidated. Here, we demonstrate that merlin expression is heterogeneous in 1 NF2 gene-negative and 3 NF2 gene-positive World Health Organization grade I meningiomas. In the NF2 gene-positive meningiomas, regions with low levels of merlin (tumor rims) had greater numbers of cells with nuclear YAP versus regions with high merlin levels (tumor cores). Merlin expression and YAP phosphorylation were also affected by cell density in the IOMM-Lee and HKBMM human meningioma cell lines; nuclear localization of YAP was regulated by cell density and extracellular matrix (ECM) stiffness in IOMM-Lee cells. These results suggest that cell density and ECM stiffness may contribute to the heterogeneous loss of merlin and increased nuclear YAP expression in human meningiomas.
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71
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Yip AK, Chiam KH, Matsudaira P. Traction stress analysis and modeling reveal that amoeboid migration in confined spaces is accompanied by expansive forces and requires the structural integrity of the membrane-cortex interactions. Integr Biol (Camb) 2015; 7:1196-211. [PMID: 26050549 DOI: 10.1039/c4ib00245h] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Leukocytes and tumor cells migrate via rapid shape changes in an amoeboid-like manner, distinct from mesenchymal cells such as fibroblasts. However, the mechanisms of how rapid shape changes are caused and how they lead to migration in the amoeboid mode are still unclear. In this study, we confined differentiated human promyelocytic leukemia cells between opposing surfaces of two pieces of polyacrylamide gels and characterized the mechanics of fibronectin-dependent mesenchymal versus fibronectin-independent amoeboid migration. On fibronectin-coated gels, the cells form lamellipodia and migrate mesenchymally. Whereas in the absence of cell-substrate adhesions through fibronectin, the same cells migrate by producing blebs and "chimneying" between the gel sheets. To identify the orientation and to quantify the magnitude of the traction forces, we found by traction force microscopy that expanding blebs push into the gels and generate anchoring stresses whose magnitude increases with decreasing gap size while the resulting migration speed is highest at an intermediate gap size. To understand why there exists such an optimal gap size for migration, we developed a computational model and showed that the chimneying speed depends on both the magnitude of intracellular pressure as well as the distribution of blebs around the cell periphery. The model also predicts that the optimal gap size increases with weakening cell membrane to actin cortex adhesion strength. We verified this prediction experimentally, by weakening the membrane-cortex adhesion strength using the ezrin inhibitor, baicalein. Thus, the chimneying mode of amoeboid migration requires a balance between intracellular pressure and membrane-cortex adhesion strength.
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Affiliation(s)
- Ai Kia Yip
- A*STAR Bioinformatics Institute, 30 Biopolis Street, #07-01 Matrix, Singapore 138671, Singapore.
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72
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Jansen KA, Donato DM, Balcioglu HE, Schmidt T, Danen EHJ, Koenderink GH. A guide to mechanobiology: Where biology and physics meet. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:3043-52. [PMID: 25997671 DOI: 10.1016/j.bbamcr.2015.05.007] [Citation(s) in RCA: 176] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 04/28/2015] [Accepted: 05/02/2015] [Indexed: 02/08/2023]
Abstract
Cells actively sense and process mechanical information that is provided by the extracellular environment to make decisions about growth, motility and differentiation. It is important to understand the underlying mechanisms given that deregulation of the mechanical properties of the extracellular matrix (ECM) is implicated in various diseases, such as cancer and fibrosis. Moreover, matrix mechanics can be exploited to program stem cell differentiation for organ-on-chip and regenerative medicine applications. Mechanobiology is an emerging multidisciplinary field that encompasses cell and developmental biology, bioengineering and biophysics. Here we provide an introductory overview of the key players important to cellular mechanobiology, taking a biophysical perspective and focusing on a comparison between flat versus three dimensional substrates. This article is part of a Special Issue entitled: Mechanobiology.
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Affiliation(s)
- Karin A Jansen
- Systems Biophysics Department, FOM Institute AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
| | - Dominique M Donato
- Physics of Life Processes, Huygens-Kamerlingh Onnes Laboratory, Leiden University, Niels Bohrweg 2, 2333 CA Leiden, The Netherlands
| | - Hayri E Balcioglu
- Faculty of Science, Leiden Academic Center for Drug Research, Toxicology, Leiden University, Einsteinweg 55, 2333 CC Leiden, The Netherlands
| | - Thomas Schmidt
- Physics of Life Processes, Huygens-Kamerlingh Onnes Laboratory, Leiden University, Niels Bohrweg 2, 2333 CA Leiden, The Netherlands
| | - Erik H J Danen
- Faculty of Science, Leiden Academic Center for Drug Research, Toxicology, Leiden University, Einsteinweg 55, 2333 CC Leiden, The Netherlands
| | - Gijsje H Koenderink
- Systems Biophysics Department, FOM Institute AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
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73
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Mechanical stimulation induces formin-dependent assembly of a perinuclear actin rim. Proc Natl Acad Sci U S A 2015; 112:E2595-601. [PMID: 25941386 DOI: 10.1073/pnas.1504837112] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Cells constantly sense and respond to mechanical signals by reorganizing their actin cytoskeleton. Although a number of studies have explored the effects of mechanical stimuli on actin dynamics, the immediate response of actin after force application has not been studied. We designed a method to monitor the spatiotemporal reorganization of actin after cell stimulation by local force application. We found that force could induce transient actin accumulation in the perinuclear region within ∼ 2 min. This actin reorganization was triggered by an intracellular Ca(2+) burst induced by force application. Treatment with the calcium ionophore A23187 recapitulated the force-induced perinuclear actin remodeling. Blocking of actin polymerization abolished this process. Overexpression of Klarsicht, ANC-1, Syne Homology (KASH) domain to displace nesprins from the nuclear envelope did not abolish Ca(2+)-dependent perinuclear actin assembly. However, the endoplasmic reticulum- and nuclear membrane-associated inverted formin-2 (INF2), a potent actin polymerization activator (mutations of which are associated with several genetic diseases), was found to be important for perinuclear actin assembly. The perinuclear actin rim structure colocalized with INF2 on stimulation, and INF2 depletion resulted in attenuation of the rim formation. Our study suggests that cells can respond rapidly to external force by remodeling perinuclear actin in a unique Ca(2+)- and INF2-dependent manner.
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74
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Goonoo N, Bhaw-Luximon A, Rodriguez IA, Wesner D, Schönherr H, Bowlin GL, Jhurry D. Poly(ester-ether)s: III. assessment of cell behaviour on nanofibrous scaffolds of PCL, PLLA and PDX blended with amorphous PMeDX. J Mater Chem B 2015; 3:673-687. [DOI: 10.1039/c4tb01350f] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
SEM images of HDF cells on scaffolds: (a) PCL/PMeDX: 93/7-good adhesion and proliferation, (b) PDX/PMeDX: 98/2-good adhesion, proliferation & infiltration and (c) PLLA/PMeDX: 85/15-good proliferation and infiltration.
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Affiliation(s)
- N. Goonoo
- ANDI Centre of Excellence for Biomedical and Biomaterials Research
- University of Mauritius
- Réduit
- Mauritius
| | - A. Bhaw-Luximon
- ANDI Centre of Excellence for Biomedical and Biomaterials Research
- University of Mauritius
- Réduit
- Mauritius
| | - I. A. Rodriguez
- Biomedical Engineering Department
- University of Memphis
- Memphis
- USA
| | - D. Wesner
- Physical Chemistry I
- Department of Chemistry and Biology
- University of Siegen
- 57076 Siegen
- Germany
| | - H. Schönherr
- Physical Chemistry I
- Department of Chemistry and Biology
- University of Siegen
- 57076 Siegen
- Germany
| | - G. L. Bowlin
- Biomedical Engineering Department
- University of Memphis
- Memphis
- USA
| | - D. Jhurry
- ANDI Centre of Excellence for Biomedical and Biomaterials Research
- University of Mauritius
- Réduit
- Mauritius
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75
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Nam KH, Jamilpour N, Mfoumou E, Wang FY, Zhang DD, Wong PK. Probing mechanoregulation of neuronal differentiation by plasma lithography patterned elastomeric substrates. Sci Rep 2014; 4:6965. [PMID: 25376886 PMCID: PMC4223667 DOI: 10.1038/srep06965] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 10/22/2014] [Indexed: 01/14/2023] Open
Abstract
Cells sense and interpret mechanical cues, including cell-cell and cell-substrate interactions, in the microenvironment to collectively regulate various physiological functions. Understanding the influences of these mechanical factors on cell behavior is critical for fundamental cell biology and for the development of novel strategies in regenerative medicine. Here, we demonstrate plasma lithography patterning on elastomeric substrates for elucidating the influences of mechanical cues on neuronal differentiation and neuritogenesis. The neuroblastoma cells form neuronal spheres on plasma-treated regions, which geometrically confine the cells over two weeks. The elastic modulus of the elastomer is controlled simultaneously by the crosslinker concentration. The cell-substrate mechanical interactions are also investigated by controlling the size of neuronal spheres with different cell seeding densities. These physical cues are shown to modulate with the formation of focal adhesions, neurite outgrowth, and the morphology of neuroblastoma. By systematic adjustment of these cues, along with computational biomechanical analysis, we demonstrate the interrelated mechanoregulatory effects of substrate elasticity and cell size. Taken together, our results reveal that the neuronal differentiation and neuritogenesis of neuroblastoma cells are collectively regulated via the cell-substrate mechanical interactions.
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Affiliation(s)
- Ki-Hwan Nam
- 1] Department of Aerospace and Mechanical Engineering, The University of Arizona, Tucson, Arizona 85721, USA [2] Centre for Analytical Instrumentation Development, The Korea Basic Science Institute, Deajeon305-806, Korea
| | - Nima Jamilpour
- Department of Aerospace and Mechanical Engineering, The University of Arizona, Tucson, Arizona 85721, USA
| | - Etienne Mfoumou
- Department of Aerospace and Mechanical Engineering, The University of Arizona, Tucson, Arizona 85721, USA
| | - Fei-Yue Wang
- The Key Laboratory for Complex Systems and Intelligence Science, The Institute of Automation, Chinese Academy of Sciences, Beijing, China
| | - Donna D Zhang
- Department of Pharmacology and Toxicology, The University of Arizona, Tucson, Arizona. 85721, USA
| | - Pak Kin Wong
- Department of Aerospace and Mechanical Engineering, The University of Arizona, Tucson, Arizona 85721, USA
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76
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Zhang QY, Zhang YY, Xie J, Li CX, Chen WY, Liu BL, Wu XA, Li SN, Huo B, Jiang LH, Zhao HC. Stiff substrates enhance cultured neuronal network activity. Sci Rep 2014; 4:6215. [PMID: 25163607 PMCID: PMC4147369 DOI: 10.1038/srep06215] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Accepted: 08/07/2014] [Indexed: 11/09/2022] Open
Abstract
The mechanical property of extracellular matrix and cell-supporting substrates is known to modulate neuronal growth, differentiation, extension and branching. Here we show that substrate stiffness is an important microenvironmental cue, to which mouse hippocampal neurons respond and integrate into synapse formation and transmission in cultured neuronal network. Hippocampal neurons were cultured on polydimethylsiloxane substrates fabricated to have similar surface properties but a 10-fold difference in Young's modulus. Voltage-gated Ca(2+) channel currents determined by patch-clamp recording were greater in neurons on stiff substrates than on soft substrates. Ca(2+) oscillations in cultured neuronal network monitored using time-lapse single cell imaging increased in both amplitude and frequency among neurons on stiff substrates. Consistently, synaptic connectivity recorded by paired recording was enhanced between neurons on stiff substrates. Furthermore, spontaneous excitatory postsynaptic activity became greater and more frequent in neurons on stiff substrates. Evoked excitatory transmitter release and excitatory postsynaptic currents also were heightened at synapses between neurons on stiff substrates. Taken together, our results provide compelling evidence to show that substrate stiffness is an important biophysical factor modulating synapse connectivity and transmission in cultured hippocampal neuronal network. Such information is useful in designing instructive scaffolds or supporting substrates for neural tissue engineering.
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Affiliation(s)
- Quan-You Zhang
- 1] Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, China [2] College of Mechanics, Taiyuan University of Technology, China [3]
| | - Yan-Yan Zhang
- 1] Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, China [2]
| | - Jing Xie
- Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, China
| | - Chen-Xu Li
- Medical School, Datong University, China
| | - Wei-Yi Chen
- College of Mechanics, Taiyuan University of Technology, China
| | - Bai-Lin Liu
- Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, China
| | - Xiao-an Wu
- Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, China
| | - Shu-Na Li
- Biomechanics and Biomaterials Laboratory, Department of Applied Mechanics, School of Aerospace Engineering, Beijing Institute of Technology, China
| | - Bo Huo
- Biomechanics and Biomaterials Laboratory, Department of Applied Mechanics, School of Aerospace Engineering, Beijing Institute of Technology, China
| | - Lin-Hua Jiang
- 1] School of Biomedical Sciences, University of Leeds, United Kingdom [2] Department of Physiology and Neurobiology, School of Basic Medical Sciences, Xinxiang Medical University, China
| | - Hu-Cheng Zhao
- Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, China
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77
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McAndrews KM, McGrail DJ, Quach ND, Dawson MR. Spatially coordinated changes in intracellular rheology and extracellular force exertion during mesenchymal stem cell differentiation. Phys Biol 2014; 11:056004. [PMID: 25156989 DOI: 10.1088/1478-3975/11/5/056004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The mechanical properties within the cell are regulated by the organization of the actin cytoskeleton, which is linked to the extracellular environment through focal adhesion proteins that transmit force. Chemical and mechanical stimuli alter the organization of cytoskeletal actin, which results in changes in cell shape, adhesion, and differentiation. By combining particle-tracking microrheology and traction force cytometry, we can monitor the mechanical properties of the actin meshwork and determine how changes in the intracellular network contribute to force generation. In this study, we investigated the effects of chemical (differentiation factors) and mechanical (substrate rigidity) stimuli important in mesenchymal stem cell (MSC) differentiation on the intracellular mechanics and traction stress generation. We found the presence of adipogenic factors resulted in stiffening of the actin meshwork regardless of substrate rigidity. In contrast, these factors increased traction stresses on hard substrates, which was associated with increased expression of contractility genes. Furthermore, MSCs cultured on hard substrates expressed both adipogenic and osteogenic markers indicative of mixed differentiation. On hard substrates, heterogeneity in the local elastic modulus-traction stress correlation was also increased in response to adipogenic factors, indicating that these mechanical properties may be reflective of differences in the level of MSC differentiation. These results suggest intracellular rheology and traction stress generation are spatially regulated and contribute insight into how single cell mechanical forces contribute to MSC differentiation.
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Affiliation(s)
- Kathleen M McAndrews
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
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78
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Miyoshi H, Adachi T. Topography design concept of a tissue engineering scaffold for controlling cell function and fate through actin cytoskeletal modulation. TISSUE ENGINEERING PART B-REVIEWS 2014; 20:609-27. [PMID: 24720435 DOI: 10.1089/ten.teb.2013.0728] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The physiological role of the actin cytoskeleton is well known: it provides mechanical support and endogenous force generation for formation of a cell shape and for migration. Furthermore, a growing number of studies have demonstrated another significant role of the actin cytoskeleton: it offers dynamic epigenetic memory for guiding cell fate, in particular, proliferation and differentiation. Because instantaneous imbalance in the mechanical homeostasis is adjusted through actin remodeling, a synthetic extracellular matrix (ECM) niche as a source of topographical and mechanical cues is expected to be effective at modulation of the actin cytoskeleton. In this context, the synthetic ECM niche determines cell migration, proliferation, and differentiation, all of which have to be controlled in functional tissue engineering scaffolds to ensure proper regulation of tissue/organ formation, maintenance of tissue integrity and repair, and regeneration. Here, with an emphasis on the epigenetic role of the actin cytoskeletal system, we propose a design concept of micro/nanotopography of a tissue engineering scaffold for control of cell migration, proliferation, and differentiation in a stable and well-defined manner, both in vitro and in vivo.
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Affiliation(s)
- Hiromi Miyoshi
- 1 Ultrahigh Precision Optics Technology Team , RIKEN Center for Advanced Photonics, Saitama, Japan
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79
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Piacentini N, Verkhovsky AB, Gabella C, Meister JJ, Vianay B. Ultra-soft cantilevers and 3-D micro-patterned substrates for contractile bundle tension measurement in living cells. LAB ON A CHIP 2014; 14:2539-2547. [PMID: 24867825 DOI: 10.1039/c4lc00188e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Actin-myosin microfilament bundles or stress-fibers are the principal tension-generating structures in the cell. Their mechanical properties are critical for cell shape, motion, and interaction with other cells and extracellular matrix, but were so far difficult to access in a living cell. Here we propose a micro-fabricated two-component setup for direct tension measurement on a peripheral bundle within an intact cell. We used 3-D substrates made of silicon elastomer to elevate the cell making the filament bundle at its border accessible from the side, and employed an ultra-soft (spring constant 0.78 nN μm(-1)) epoxy-based cantilever for mechanical probing. With this setup we were able for the first time to measure the tension in peripheral actin bundles in living primary fibroblasts spread on a rigid substrate.
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Affiliation(s)
- Niccolò Piacentini
- Laboratory of Cell Biophysics, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
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80
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Guo AK, Hou YY, Hirata H, Yamauchi S, Yip AK, Chiam KH, Tanaka N, Sawada Y, Kawauchi K. Loss of p53 enhances NF-κB-dependent lamellipodia formation. J Cell Physiol 2014; 229:696-704. [PMID: 24647813 DOI: 10.1002/jcp.24505] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Revised: 09/30/2013] [Accepted: 10/23/2013] [Indexed: 12/29/2022]
Abstract
Tumor suppressor p53 prevents tumorigenesis and tumor growth by suppressing the activation of several transcription factors, including nuclear factor-κB (NF-κB) and STAT3. On the other hand, p53 stimulates actin cytoskeleton remodeling and integrin-related signaling cascades. Here, we examined the p53-mediated link between regulation of the actin cytoskeleton and activation of NF-κB and STAT3 in MCF-7 cells and mouse embryonic fibroblasts (MEFs). In the absence of p53, STAT3 was constitutively activated. This activation was attenuated by depleting the expression of p65, a component of NF-κB. Integrin β3 expression and lamellipodia formation were also downregulated by NF-κB depletion. Inhibition of integrin αvβ3, Rac1 or Arp2/3, which diminished lamellipodia formation, suppressed STAT3 activation induced by p53 depletion. These results suggest that loss of p53 leads to STAT3 activation via NF-κB-dependent lamellipodia formation. Our study proposes a novel role for p53 in modulating the actin cytoskeleton through suppression of NF-κB, which restricts STAT3 activation.
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81
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Yamauchi S, Hou YY, Guo AK, Hirata H, Nakajima W, Yip AK, Yu CH, Harada I, Chiam KH, Sawada Y, Tanaka N, Kawauchi K. p53-mediated activation of the mitochondrial protease HtrA2/Omi prevents cell invasion. ACTA ACUST UNITED AC 2014; 204:1191-207. [PMID: 24662565 PMCID: PMC3971739 DOI: 10.1083/jcb.201309107] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Oncogenic Ras induces cell transformation and promotes an invasive phenotype. The tumor suppressor p53 has a suppressive role in Ras-driven invasion. However, its mechanism remains poorly understood. Here we show that p53 induces activation of the mitochondrial protease high-temperature requirement A2 (HtrA2; also known as Omi) and prevents Ras-driven invasion by modulating the actin cytoskeleton. Oncogenic Ras increases accumulation of p53 in the cytoplasm, which promotes the translocation of p38 mitogen-activated protein kinase (MAPK) into mitochondria and induces phosphorylation of HtrA2/Omi. Concurrently, oncogenic Ras also induces mitochondrial fragmentation, irrespective of p53 expression, causing the release of HtrA2/Omi from mitochondria into the cytosol. Phosphorylated HtrA2/Omi therefore cleaves β-actin and decreases the amount of filamentous actin (F-actin) in the cytosol. This ultimately down-regulates p130 Crk-associated substrate (p130Cas)-mediated lamellipodia formation, countering the invasive phenotype initiated by oncogenic Ras. Our novel findings provide insights into the mechanism by which p53 prevents the malignant progression of transformed cells.
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Affiliation(s)
- Shota Yamauchi
- Mechanobiology Institute, Level 10, T-Lab, National University of Singapore, Singapore 117411, Singapore
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Parameswaran H, Lutchen KR, Suki B. A computational model of the response of adherent cells to stretch and changes in substrate stiffness. J Appl Physiol (1985) 2014; 116:825-34. [PMID: 24408996 DOI: 10.1152/japplphysiol.00962.2013] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Cells in the body exist in a dynamic mechanical environment where they are subject to mechanical stretch as well as changes in composition and stiffness of the underlying extracellular matrix (ECM). However, the underlying mechanisms by which cells sense and adapt to their dynamic mechanical environment, in particular to stretch, are not well understood. In this study, we hypothesized that emergent phenomena at the level of the actin network arising from active structural rearrangements driven by nonmuscle myosin II molecular motors play a major role in the cellular response to both stretch and changes in ECM stiffness. To test this hypothesis, we introduce a simple network model of actin-myosin interactions that links active self-organization of the actin network to the stiffness of the network and the traction forces generated by the network. We demonstrate that such a network replicates not only the effect of changes in substrate stiffness on cellular traction and stiffness and the dependence of rate of force development by a cell on the stiffness of its substrate, but also explains the physical response of adherent cells to transient and cyclic stretch. Our results provide strong indication that network phenomena governed by the active reorganization of the actin-myosin structure plays an important role in cellular mechanosensing and response to both changes in ECM stiffness and externally applied mechanical stretch.
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83
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Missirlis D, Spatz JP. Combined effects of PEG hydrogel elasticity and cell-adhesive coating on fibroblast adhesion and persistent migration. Biomacromolecules 2013; 15:195-205. [PMID: 24274760 DOI: 10.1021/bm4014827] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The development and use of synthetic, cross-linked, macromolecular substrates with tunable elasticity has been instrumental in revealing the mechanisms by which cells sense and respond to their mechanical microenvironment. We here describe a hydrogel based on radical-free, cross-linked poly(ethylene glycol) to study the effects of both substrate elasticity and type of adhesive coating on fibroblast adhesion and migration. Hydrogel elasticity was controlled through the structure and concentration of branched precursors, which efficiently react via Michael-type addition to produce the polymer network. We found that cell spreading and focal adhesion characteristics are dependent on elasticity for all types of coatings (RGD peptide, fibronectin, vitronectin), albeit with significant differences in magnitude. Importantly, fibroblasts migrated slower but more persistently on stiffer hydrogels, with the effects being more pronounced on fibronectin-coated substrates. Therefore, our results validate the hydrogels presented in this study as suitable for future mechanosensing studies and indicate that cell adhesion, polarity, and associated migration persistence are tuned by substrate elasticity and biochemical properties.
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Affiliation(s)
- Dimitris Missirlis
- Department of New Materials and Biosystems, Max Planck Institute for Intelligent Systems , Heisenbergstr. 3, 70569 Stuttgart, Germany
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84
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Zhang X, Zhang Y, Chen W, Xu L, Wei S, Zheng Y, Zhai M. Biological behavior of fibroblast on contractile collagen hydrogel crosslinked by γ-irradiation. J Biomed Mater Res A 2013; 102:2669-79. [DOI: 10.1002/jbm.a.34938] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Revised: 08/14/2013] [Accepted: 08/20/2013] [Indexed: 01/16/2023]
Affiliation(s)
- Xiangmei Zhang
- Beijing Key Laboratory for Solid Waste Utilization and Management; College of Engineering, Peking University; Beijing 100871 China
- Center for Biomedical Materials and Tissue Engineering; Academy for Advanced Interdisciplinary Studies, Peking University; Beijing 100871 China
| | - Yaqing Zhang
- Beijing Key Laboratory for Solid Waste Utilization and Management; College of Engineering, Peking University; Beijing 100871 China
- Center for Biomedical Materials and Tissue Engineering; Academy for Advanced Interdisciplinary Studies, Peking University; Beijing 100871 China
| | - Wenqiang Chen
- Center for Biomedical Materials and Tissue Engineering; Academy for Advanced Interdisciplinary Studies, Peking University; Beijing 100871 China
| | - Ling Xu
- Beijing Key Laboratory for Solid Waste Utilization and Management; College of Engineering, Peking University; Beijing 100871 China
- Center for Biomedical Materials and Tissue Engineering; Academy for Advanced Interdisciplinary Studies, Peking University; Beijing 100871 China
- Shenzhen Key Laboratory for Polymer Science; Peking University, ShenZhen Institution; Shenzhen 518057 China
| | - Shicheng Wei
- Center for Biomedical Materials and Tissue Engineering; Academy for Advanced Interdisciplinary Studies, Peking University; Beijing 100871 China
- Department of Oral and Maxillofacial Surgery; School and Hospital of Stomatology, Peking University; Beijing 100081 China
| | - Yufeng Zheng
- Center for Biomedical Materials and Tissue Engineering; Academy for Advanced Interdisciplinary Studies, Peking University; Beijing 100871 China
| | - Maolin Zhai
- Beijing National Laboratory for Molecular Sciences, Department of Applied Chemistry; College of Chemistry and Molecular Engineering, Peking University; Beijing 100871 China
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85
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del Álamo JC, Meili R, Álvarez-González B, Alonso-Latorre B, Bastounis E, Firtel R, Lasheras JC. Three-dimensional quantification of cellular traction forces and mechanosensing of thin substrata by fourier traction force microscopy. PLoS One 2013; 8:e69850. [PMID: 24023712 PMCID: PMC3762859 DOI: 10.1371/journal.pone.0069850] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Accepted: 06/17/2013] [Indexed: 12/02/2022] Open
Abstract
We introduce a novel three-dimensional (3D) traction force microscopy (TFM) method motivated by the recent discovery that cells adhering on plane surfaces exert both in-plane and out-of-plane traction stresses. We measure the 3D deformation of the substratum on a thin layer near its surface, and input this information into an exact analytical solution of the elastic equilibrium equation. These operations are performed in the Fourier domain with high computational efficiency, allowing to obtain the 3D traction stresses from raw microscopy images virtually in real time. We also characterize the error of previous two-dimensional (2D) TFM methods that neglect the out-of-plane component of the traction stresses. This analysis reveals that, under certain combinations of experimental parameters (cell size, substratums' thickness and Poisson's ratio), the accuracy of 2D TFM methods is minimally affected by neglecting the out-of-plane component of the traction stresses. Finally, we consider the cell's mechanosensing of substratum thickness by 3D traction stresses, finding that, when cells adhere on thin substrata, their out-of-plane traction stresses can reach four times deeper into the substratum than their in-plane traction stresses. It is also found that the substratum stiffness sensed by applying out-of-plane traction stresses may be up to 10 times larger than the stiffness sensed by applying in-plane traction stresses.
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Affiliation(s)
- Juan C. del Álamo
- Mechanical and Aerospace Engineering Department, University of California San Diego, La Jolla, California, United States of America
- Institute for Engineering in Medicine, University of California San Diego, La Jolla, California, United States of America
| | - Ruedi Meili
- Mechanical and Aerospace Engineering Department, University of California San Diego, La Jolla, California, United States of America
- Division of Cell and Developmental Biology, University of California San Diego, La Jolla, California, United States of America
| | - Begoña Álvarez-González
- Mechanical and Aerospace Engineering Department, University of California San Diego, La Jolla, California, United States of America
| | - Baldomero Alonso-Latorre
- Mechanical and Aerospace Engineering Department, University of California San Diego, La Jolla, California, United States of America
| | - Effie Bastounis
- Mechanical and Aerospace Engineering Department, University of California San Diego, La Jolla, California, United States of America
- Division of Cell and Developmental Biology, University of California San Diego, La Jolla, California, United States of America
- Bioengineering Department, University of California San Diego, La Jolla, California, United States of America
| | - Richard Firtel
- Division of Cell and Developmental Biology, University of California San Diego, La Jolla, California, United States of America
| | - Juan C. Lasheras
- Mechanical and Aerospace Engineering Department, University of California San Diego, La Jolla, California, United States of America
- Institute for Engineering in Medicine, University of California San Diego, La Jolla, California, United States of America
- Bioengineering Department, University of California San Diego, La Jolla, California, United States of America
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86
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Loosli Y, Labouesse C, Luginbuehl R, Meister JJ, Snedeker JG, Vianay B. An actin length threshold regulates adhesion maturation at the lamellipodium/lamellum interface. Integr Biol (Camb) 2013; 5:865-76. [DOI: 10.1039/c3ib20282h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Y. Loosli
- Department of Orthopedics, University of Zurich, Balgrist University Hospital, Zurich, Switzerland
- Institute for Biomechanics, ETH Zurich, Switzerland
- RMS foundation, Bettlach, Switzerland
| | - C. Labouesse
- Laboratory of Cell Biophysics, Ecole Polytechnique Fédérale de Lausanne - SB - IPSB - LCB, Station 19, 1015 Lausanne, Switzerland. Fax: +41 21 693 83 05; Tel: +41 21 693 83 37
| | | | - J.-J. Meister
- Laboratory of Cell Biophysics, Ecole Polytechnique Fédérale de Lausanne - SB - IPSB - LCB, Station 19, 1015 Lausanne, Switzerland. Fax: +41 21 693 83 05; Tel: +41 21 693 83 37
| | - J. G. Snedeker
- Department of Orthopedics, University of Zurich, Balgrist University Hospital, Zurich, Switzerland
- Institute for Biomechanics, ETH Zurich, Switzerland
| | - B. Vianay
- Laboratory of Cell Biophysics, Ecole Polytechnique Fédérale de Lausanne - SB - IPSB - LCB, Station 19, 1015 Lausanne, Switzerland. Fax: +41 21 693 83 05; Tel: +41 21 693 83 37
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