1
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Denisin AK, Kim H, Riedel-Kruse IH, Pruitt BL. Field Guide to Traction Force Microscopy. Cell Mol Bioeng 2024; 17:87-106. [PMID: 38737454 PMCID: PMC11082129 DOI: 10.1007/s12195-024-00801-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2024] [Accepted: 03/26/2024] [Indexed: 05/14/2024] Open
Abstract
Introduction Traction force microscopy (TFM) is a widely used technique to measure cell contractility on compliant substrates that mimic the stiffness of human tissues. For every step in a TFM workflow, users make choices which impact the quantitative results, yet many times the rationales and consequences for making these decisions are unclear. We have found few papers which show the complete experimental and mathematical steps of TFM, thus obfuscating the full effects of these decisions on the final output. Methods Therefore, we present this "Field Guide" with the goal to explain the mathematical basis of common TFM methods to practitioners in an accessible way. We specifically focus on how errors propagate in TFM workflows given specific experimental design and analytical choices. Results We cover important assumptions and considerations in TFM substrate manufacturing, substrate mechanical properties, imaging techniques, image processing methods, approaches and parameters used in calculating traction stress, and data-reporting strategies. Conclusions By presenting a conceptual review and analysis of TFM-focused research articles published over the last two decades, we provide researchers in the field with a better understanding of their options to make more informed choices when creating TFM workflows depending on the type of cell being studied. With this review, we aim to empower experimentalists to quantify cell contractility with confidence. Supplementary Information The online version contains supplementary material available at 10.1007/s12195-024-00801-6.
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Affiliation(s)
| | - Honesty Kim
- Department of Bioengineering, Stanford University, Stanford, CA 94305 USA
- Present Address: The Department of Pharmaceutical Chemistry, University of California, San Francisco, CA 94158 USA
- Department of Molecular and Cellular Biology, and (by courtesy) Departments of Biomedical Engineering, Applied Mathematics, and Physics, University of Arizona, Tucson, AZ 85721 USA
| | - Ingmar H. Riedel-Kruse
- Department of Molecular and Cellular Biology, and (by courtesy) Departments of Biomedical Engineering, Applied Mathematics, and Physics, University of Arizona, Tucson, AZ 85721 USA
| | - Beth L. Pruitt
- Departments of Bioengineering and Mechanical Engineering, University of California Santa Barbara, Santa Barbara, CA 93106 USA
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2
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Jeffreys N, Brockman JM, Zhai Y, Ingber DE, Mooney DJ. Mechanical forces amplify TCR mechanotransduction in T cell activation and function. APPLIED PHYSICS REVIEWS 2024; 11:011304. [PMID: 38434676 PMCID: PMC10848667 DOI: 10.1063/5.0166848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 12/08/2023] [Indexed: 03/05/2024]
Abstract
Adoptive T cell immunotherapies, including engineered T cell receptor (eTCR) and chimeric antigen receptor (CAR) T cell immunotherapies, have shown efficacy in treating a subset of hematologic malignancies, exhibit promise in solid tumors, and have many other potential applications, such as in fibrosis, autoimmunity, and regenerative medicine. While immunoengineering has focused on designing biomaterials to present biochemical cues to manipulate T cells ex vivo and in vivo, mechanical cues that regulate their biology have been largely underappreciated. This review highlights the contributions of mechanical force to several receptor-ligand interactions critical to T cell function, with central focus on the TCR-peptide-loaded major histocompatibility complex (pMHC). We then emphasize the role of mechanical forces in (i) allosteric strengthening of the TCR-pMHC interaction in amplifying ligand discrimination during T cell antigen recognition prior to activation and (ii) T cell interactions with the extracellular matrix. We then describe approaches to design eTCRs, CARs, and biomaterials to exploit TCR mechanosensitivity in order to potentiate T cell manufacturing and function in adoptive T cell immunotherapy.
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Affiliation(s)
| | | | - Yunhao Zhai
- Wyss Institute for Biologically Inspired Engineering, Boston, Massachusetts 02115, USA
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3
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Singh Y, Hocky GM. Improved Prediction of Molecular Response to Pulling by Combining Force Tempering with Replica Exchange Methods. J Phys Chem B 2024; 128:706-715. [PMID: 38230998 PMCID: PMC10823473 DOI: 10.1021/acs.jpcb.3c07081] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 01/02/2024] [Accepted: 01/03/2024] [Indexed: 01/18/2024]
Abstract
Small mechanical forces play important functional roles in many crucial cellular processes, including in the dynamic behavior of the cytoskeleton and in the regulation of osmotic pressure through membrane-bound proteins. Molecular simulations offer the promise of being able to design the behavior of proteins that sense and respond to these forces. However, it is difficult to predict and identify the effect of the relevant piconewton (pN) scale forces due to their small magnitude. Previously, we introduced the Infinite Switch Simulated Tempering in Force (FISST) method, which allows one to estimate the effect of a range of applied forces from a single molecular dynamics simulation, and also demonstrated that FISST additionally accelerates sampling of a molecule's conformational landscape. For some problems, we find that this acceleration is not sufficient to capture all relevant conformational fluctuations, and hence, here we demonstrate that FISST can be combined with either temperature replica exchange or solute tempering approaches to produce a hybrid method that enables more robust prediction of the effect of small forces on molecular systems.
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Affiliation(s)
- Yuvraj Singh
- Department
of Chemistry, New York University, New York, New York 10003, United States
| | - Glen M. Hocky
- Department
of Chemistry, New York University, New York, New York 10003, United States
- Simons
Center for Computational Physical Chemistry, New York University, New York, New York 10003, United States
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4
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Suga K, Yamakado T, Saito S. Dual Ratiometric Fluorescence Monitoring of Mechanical Polymer Chain Stretching and Subsequent Strain-Induced Crystallization. J Am Chem Soc 2023. [PMID: 38051032 DOI: 10.1021/jacs.3c09175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2023]
Abstract
Tracking the behavior of mechanochromic molecules provides valuable insights into force transmission and associated microstructural changes in soft materials under load. Herein, we report a dual ratiometric fluorescence (FL) analysis for monitoring both mechanical polymer chain stretching and strain-induced crystallization (SIC) of polymers. SIC has recently attracted renewed attention as an effective mechanism for improving the mechanical properties of polymers. A polyurethane (PU) film incorporating a trace of a dual-emissive flapping force probe (N-FLAP, 0.008 wt %) exhibited a blue-to-green FL spectral change in a low-stress region (<20 MPa), resulting from conformational planarization of the probe in mechanically stretched polymer chains. More importantly, at higher probe concentrations (∼0.65 wt %), the PU film showed a second spectral change from green to yellow during the SIC growth (20-65 MPa) due to self-absorption of scattered FL in a short wavelength region. The reversibility of these spectral changes was demonstrated by load-unload cycles. With these results in hand, the degrees of the polymer chain stretching and the SIC were quantitatively mapped and monitored by dual ratiometric imaging based on different FL ratios (I525/I470 and I525/I600). Simultaneous analysis of these two mappings revealed a spatiotemporal gap in the distribution of the polymer chain stretching and the SIC. The combinational use of the dual-emissive force probe and the ratiometric FL imaging is a universal approach for the development of soft matter physics.
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Affiliation(s)
- Kensuke Suga
- Graduate School of Science, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan
| | - Takuya Yamakado
- Graduate School of Science, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan
| | - Shohei Saito
- Graduate School of Science, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan
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5
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Amiri S, Muresan C, Shang X, Huet-Calderwood C, Schwartz MA, Calderwood DA, Murrell M. Intracellular tension sensor reveals mechanical anisotropy of the actin cytoskeleton. Nat Commun 2023; 14:8011. [PMID: 38049429 PMCID: PMC10695988 DOI: 10.1038/s41467-023-43612-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 11/15/2023] [Indexed: 12/06/2023] Open
Abstract
The filamentous actin (F-actin) cytoskeleton is a composite material consisting of cortical actin and bundled F-actin stress fibers, which together mediate the mechanical behaviors of the cell, from cell division to cell migration. However, as mechanical forces are typically measured upon transmission to the extracellular matrix, the internal distribution of forces within the cytoskeleton is unknown. Likewise, how distinct F-actin architectures contribute to the generation and transmission of mechanical forces is unclear. Therefore, we have developed a molecular tension sensor that embeds into the F-actin cytoskeleton. Using this sensor, we measure tension within stress fibers and cortical actin, as the cell is subject to uniaxial stretch. We find that the mechanical response, as measured by FRET, depends on the direction of applied stretch relative to the cell's axis of alignment. When the cell is aligned parallel to the direction of the stretch, stress fibers and cortical actin both accumulate tension. By contrast, when aligned perpendicular to the direction of stretch, stress fibers relax tension while the cortex accumulates tension, indicating mechanical anisotropy within the cytoskeleton. We further show that myosin inhibition regulates this anisotropy. Thus, the mechanical anisotropy of the cell and the coordination between distinct F-actin architectures vary and depend upon applied load.
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Affiliation(s)
- Sorosh Amiri
- Systems Biology Institute, 850 West Campus Drive, Yale University, West Haven, CT, 06516, USA
- Department of Mechanical Engineering and Material Science, 17 Hillhouse Ave, Yale University, New Haven, CT, 06511, USA
| | - Camelia Muresan
- Systems Biology Institute, 850 West Campus Drive, Yale University, West Haven, CT, 06516, USA
- Department of Biomedical Engineering, 17 Hillhouse Ave, Yale University, New Haven, CT, 06511, USA
| | - Xingbo Shang
- Systems Biology Institute, 850 West Campus Drive, Yale University, West Haven, CT, 06516, USA
- Department of Biomedical Engineering, 17 Hillhouse Ave, Yale University, New Haven, CT, 06511, USA
| | | | - Martin A Schwartz
- Department of Biomedical Engineering, 17 Hillhouse Ave, Yale University, New Haven, CT, 06511, USA
- Department of Cell Biology, 333 Cedar St, Yale University, New Haven, CT, 06510, USA
- Yale Cardiovascular Research Center, 300 George St, New Haven, CT, 06511, USA
| | - David A Calderwood
- Department of Pharmacology, 333 Cedar St, Yale University, New Haven, CT, 06510, USA
- Department of Cell Biology, 333 Cedar St, Yale University, New Haven, CT, 06510, USA
| | - Michael Murrell
- Systems Biology Institute, 850 West Campus Drive, Yale University, West Haven, CT, 06516, USA.
- Department of Biomedical Engineering, 17 Hillhouse Ave, Yale University, New Haven, CT, 06511, USA.
- Department of Physics, 217 Prospect Street, Yale University, New Haven, CT, 06511, USA.
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6
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Yaganoglu S, Kalyviotis K, Vagena-Pantoula C, Jülich D, Gaub BM, Welling M, Lopes T, Lachowski D, Tang SS, Del Rio Hernandez A, Salem V, Müller DJ, Holley SA, Vermot J, Shi J, Helassa N, Török K, Pantazis P. Highly specific and non-invasive imaging of Piezo1-dependent activity across scales using GenEPi. Nat Commun 2023; 14:4352. [PMID: 37468521 PMCID: PMC10356793 DOI: 10.1038/s41467-023-40134-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 07/11/2023] [Indexed: 07/21/2023] Open
Abstract
Mechanosensing is a ubiquitous process to translate external mechanical stimuli into biological responses. Piezo1 ion channels are directly gated by mechanical forces and play an essential role in cellular mechanotransduction. However, readouts of Piezo1 activity are mainly examined by invasive or indirect techniques, such as electrophysiological analyses and cytosolic calcium imaging. Here, we introduce GenEPi, a genetically-encoded fluorescent reporter for non-invasive optical monitoring of Piezo1-dependent activity. We demonstrate that GenEPi has high spatiotemporal resolution for Piezo1-dependent stimuli from the single-cell level to that of the entire organism. GenEPi reveals transient, local mechanical stimuli in the plasma membrane of single cells, resolves repetitive contraction-triggered stimulation of beating cardiomyocytes within microtissues, and allows for robust and reliable monitoring of Piezo1-dependent activity in vivo. GenEPi will enable non-invasive optical monitoring of Piezo1 activity in mechanochemical feedback loops during development, homeostatic regulation, and disease.
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Affiliation(s)
- Sine Yaganoglu
- Department of Biosystems Science and Engineering, Eidgenössische Technische Hochschule (ETH) Zurich, Basel, Switzerland
| | | | | | - Dörthe Jülich
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - Benjamin M Gaub
- Department of Biosystems Science and Engineering, Eidgenössische Technische Hochschule (ETH) Zurich, Basel, Switzerland
| | - Maaike Welling
- Department of Biosystems Science and Engineering, Eidgenössische Technische Hochschule (ETH) Zurich, Basel, Switzerland
- Department of Bioengineering, Imperial College London, London, UK
| | - Tatiana Lopes
- Section of Investigative Medicine, Department of Metabolism, Digestion, and Reproduction, Imperial College London, London, UK
| | | | - See Swee Tang
- Department of Bioengineering, Imperial College London, London, UK
| | | | - Victoria Salem
- Department of Bioengineering, Imperial College London, London, UK
| | - Daniel J Müller
- Department of Biosystems Science and Engineering, Eidgenössische Technische Hochschule (ETH) Zurich, Basel, Switzerland
| | - Scott A Holley
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - Julien Vermot
- Department of Bioengineering, Imperial College London, London, UK
| | - Jian Shi
- Leeds Institute of Cardiovascular and Metabolic Medicine, LIGHT Laboratories, University of Leeds, Leeds, UK
| | - Nordine Helassa
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, UK
- Department of Biochemistry, Cell and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK
| | - Katalin Török
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, UK
| | - Periklis Pantazis
- Department of Biosystems Science and Engineering, Eidgenössische Technische Hochschule (ETH) Zurich, Basel, Switzerland.
- Department of Bioengineering, Imperial College London, London, UK.
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7
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Windgasse L, Grashoff C. Multiplexed Molecular Tension Sensor Measurements Using PIE-FLIM. Methods Mol Biol 2023; 2600:221-237. [PMID: 36587101 DOI: 10.1007/978-1-0716-2851-5_15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Genetically encoded Förster Resonance Energy Transfer (FRET)-based tension sensors were developed to enable the quantification of piconewton (pN)-scale forces that act across distinct proteins in living cells and organisms. An important extension of this technology is the multiplexing of tension sensors to monitor several independent FRET probes in parallel. Here we describe how pulsed interleaved excitation (PIE)-fluorescence lifetime imaging microscopy (FLIM) can be implemented to enable the analysis of two co-expressed tension sensor constructs. Our protocol covers all essential steps from biosensor expression and live cell PIE image acquisition to lifetime calculations.
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Affiliation(s)
- Lukas Windgasse
- Department of Quantitative Cell Biology, Institute of Integrative Cell Biology and Physiology, University of Münster, Münster, Germany
| | - Carsten Grashoff
- Department of Quantitative Cell Biology, Institute of Integrative Cell Biology and Physiology, University of Münster, Münster, Germany.
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8
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Tan M, Xu Y, Gao Z, Yuan T, Liu Q, Yang R, Zhang B, Peng L. Recent Advances in Intelligent Wearable Medical Devices Integrating Biosensing and Drug Delivery. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2108491. [PMID: 35008128 DOI: 10.1002/adma.202108491] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 12/28/2021] [Indexed: 05/27/2023]
Abstract
The primary roles of precision medicine are to perform real-time examination, administer on-demand medication, and apply instruments continuously. However, most current therapeutic systems implement these processes separately, leading to treatment interruption and limited recovery in patients. Personalized healthcare and smart medical treatment have greatly promoted research on and development of biosensing and drug-delivery integrated systems, with intelligent wearable medical devices (IWMDs) as typical systems, which have received increasing attention because of their non-invasive and customizable nature. Here, the latest progress in research on IWMDs is reviewed, including their mechanisms of integrating biosensing and on-demand drug delivery. The current challenges and future development directions of IWMDs are also discussed.
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Affiliation(s)
- Minhong Tan
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, 310058, P. R. China
- School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Yang Xu
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, 310058, P. R. China
| | - Ziqi Gao
- School of Mechanical Engineering, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Tiejun Yuan
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, 310058, P. R. China
| | - Qingjun Liu
- College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Rusen Yang
- School of Advanced Materials and Nanotechnology, Xidian University, Xian, 710126, P. R. China
| | - Bin Zhang
- School of Mechanical Engineering, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Lihua Peng
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, 310058, P. R. China
- State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau, P. R. China
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9
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Ding X, Li M, Cheng B, Wei Z, Dong Y, Xu F. Microsphere sensors for characterizing stress fields within three-dimensional extracellular matrix. Acta Biomater 2022; 141:1-13. [PMID: 34979325 DOI: 10.1016/j.actbio.2021.12.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 12/11/2021] [Accepted: 12/27/2021] [Indexed: 11/16/2022]
Abstract
Stress in the three-dimensional extracellular matrix is one of the key cues in regulating multiscale biological processes. Thus far, noticeable progress in methods and techniques (e.g., micropipette aspiration, AFM, and molecule probes) has been made to quantify stress in cell microenvironment at different length scales. Among them, the microsphere sensor-based method (MSS-based method) has emerged as an advantageous approach over conventional techniques in quantifying stress in situ and in vivo at cellular and supra-cellular scales. This method is implemented by seven sequential steps, including fabrication, modification, characterization, cell adhesion, imaging, displacement field extraction and stress calculation. Precise control of each step and inter-tunning between steps can provide quantitative characterization of stress field. However, detailed procedural information associated with each step and process has been scattered. This review aims to provide a comprehensive overview of MSS-based method, systematically summarizing the principles and research progresses. Firstly, the basic principles are introduced, and the specific experiment and calculation processes of MSS-based method are presented in detail. Then, recent advances and applications of this method are summarized. Finally, perspectives of the limitations and development trends of MSS-based method are discussed. This specific and comprehensive review would provide a guideline for the widespread application of MSS-based method as an advantageous method for in situ and in vivo stress characterization at cellular and supra-cellular scale within three-dimensional extracellular matrix. STATEMENT OF SIGNIFICANCE: In this review, a method based on a microsphere sensor (MSS-based method) as an advantageous approach over conventional techniques in quantifying stress in situ and in vivo at cellular and supra-cellular scales is introduced and discussed. This technique is implemented by seven sequential steps, including fabrication, modification, characterization, cell junction, imaging, displacement field extraction, and stress calculation. Precise control of each step and inter-tunning between steps can provide quantitative stress field. However, detailed procedural information associated with each step has been scattered. Thus, a comprehensive review collating recent advances and perspective discussions is a necessity to introduce a better option for quantifying the stress field in biological processes at the cellular and supra-cellular scales.
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Affiliation(s)
- Xin Ding
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, PR China; Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University, Xi'an 710049, PR China
| | - Moxiao Li
- State Key Laboratory of Mechanics and Control of Mechanical Structures, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, PR China
| | - Bo Cheng
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, PR China; Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University, Xi'an 710049, PR China
| | - Zhao Wei
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, PR China; Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University, Xi'an 710049, PR China
| | - Yuqing Dong
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, PR China; Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University, Xi'an 710049, PR China.
| | - Feng Xu
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, PR China; Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University, Xi'an 710049, PR China.
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10
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Stirnemann G. Recent Advances and Emerging Challenges in the Molecular Modeling of Mechanobiological Processes. J Phys Chem B 2022; 126:1365-1374. [PMID: 35143190 DOI: 10.1021/acs.jpcb.1c10715] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Many biological processes result from the effect of mechanical forces on macromolecular structures and on their interactions. In particular, the cell shape, motion, and differentiation directly depend on mechanical stimuli from the extracellular matrix or from neighboring cells. The development of experimental techniques that can measure and characterize the tiny forces acting at the cellular scale and down to the single-molecule, biomolecular level has enabled access to unprecedented details about the involved mechanisms. However, because the experimental observables often do not provide a direct atomistic picture of the corresponding phenomena, particle-based simulations performed at various scales are instrumental in complementing these experiments and in providing a molecular interpretation. Here, we will review the recent key achievements in the field, and we will highlight and discuss the many technical challenges these simulations are facing, as well as suggest future directions for improvement.
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Affiliation(s)
- Guillaume Stirnemann
- CNRS Laboratoire de Biochimie Théorique, Institut de Biologie Physico-Chimique, PSL University, Université de Paris, 13 rue Pierre et Marie Curie, 75005 Paris, France
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11
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Yamakado T, Saito S. Ratiometric Flapping Force Probe That Works in Polymer Gels. J Am Chem Soc 2022; 144:2804-2815. [PMID: 35108003 DOI: 10.1021/jacs.1c12955] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Polymer gels have recently attracted attention for their application in flexible devices, where mechanically robust gels are required. While there are many strategies to produce tough gels by suppressing nanoscale stress concentration on specific polymer chains, it is still challenging to directly verify the toughening mechanism at the molecular level. To solve this problem, the use of the flapping molecular force probe (FLAP) is promising because it can evaluate the nanoscale forces transmitted in the polymer chain network by ratiometric analysis of a stress-dependent dual fluorescence. A flexible conformational change of FLAP enables real-time and reversible responses to the nanoscale forces at the low force threshold, which is suitable for quantifying the percentage of the stressed polymer chains before structural damage. However, the previously reported FLAP only showed a negligible response in solvated environments because undesirable spontaneous planarization occurs in the excited state, even without mechanical force. Here, we have developed a new ratiometric force probe that functions in common organogels. Replacement of the anthraceneimide units in the flapping wings with pyreneimide units largely suppresses the excited-state planarization, leading to the force probe function under wet conditions. The FLAP-doped polyurethane organogel reversibly shows a dual-fluorescence response under sub-MPa compression. Moreover, the structurally modified FLAP is also advantageous in the wide dynamic range of its fluorescence response in solvent-free elastomers, enabling clearer ratiometric fluorescence imaging of the molecular-level stress concentration during crack growth in a stretched polyurethane film.
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Affiliation(s)
- Takuya Yamakado
- Graduate School of Science, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan
| | - Shohei Saito
- Graduate School of Science, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan
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12
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Carvalho E, Morais M, Ferreira H, Silva M, Guimarães S, Pêgo A. A paradigm shift: Bioengineering meets mechanobiology towards overcoming remyelination failure. Biomaterials 2022; 283:121427. [DOI: 10.1016/j.biomaterials.2022.121427] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 01/31/2022] [Accepted: 02/17/2022] [Indexed: 12/14/2022]
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13
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Kotani R, Yokoyama S, Nobusue S, Yamaguchi S, Osuka A, Yabu H, Saito S. Bridging pico-to-nanonewtons with a ratiometric force probe for monitoring nanoscale polymer physics before damage. Nat Commun 2022; 13:303. [PMID: 35027559 PMCID: PMC8758707 DOI: 10.1038/s41467-022-27972-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 12/15/2021] [Indexed: 02/07/2023] Open
Abstract
Understanding the transmission of nanoscale forces in the pico-to-nanonewton range is important in polymer physics. While physical approaches have limitations in analyzing the local force distribution in condensed environments, chemical analysis using force probes is promising. However, there are stringent requirements for probing the local forces generated before structural damage. The magnitude of those forces corresponds to the range below covalent bond scission (from 200 pN to several nN) and above thermal fluctuation (several pN). Here, we report a conformationally flexible dual-fluorescence force probe with a theoretically estimated threshold of approximately 100 pN. This probe enables ratiometric analysis of the distribution of local forces in a stretched polymer chain network. Without changing the intrinsic properties of the polymer, the force distribution was reversibly monitored in real time. Chemical control of the probe location demonstrated that the local stress concentration is twice as biased at crosslinkers than at main chains, particularly in a strain-hardening region. Due to the high sensitivity, the percentage of the stressed force probes was estimated to be more than 1000 times higher than the activation rate of a conventional mechanophore.
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Affiliation(s)
- Ryota Kotani
- Graduate School of Science, Kyoto University, Kyoto, 606-8502, Japan
| | - Soichi Yokoyama
- Graduate School of Science, Kyoto University, Kyoto, 606-8502, Japan
| | - Shunpei Nobusue
- Institute of Advanced Energy, Kyoto University, Uji, 611-0011, Japan
| | | | - Atsuhiro Osuka
- Graduate School of Science, Kyoto University, Kyoto, 606-8502, Japan
| | - Hiroshi Yabu
- WPI-Advanced Institute for Materials Research (AIMR), Tohoku University, Sendai, 980-8577, Japan.
| | - Shohei Saito
- Graduate School of Science, Kyoto University, Kyoto, 606-8502, Japan.
- PRESTO, Japan Science and Technology Agency, Kyoto, 606-8502, Japan.
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14
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Pan J, Kmieciak T, Liu YT, Wildenradt M, Chen YS, Zhao Y. Quantifying molecular- to cellular-level forces in living cells. JOURNAL OF PHYSICS D: APPLIED PHYSICS 2021; 54:483001. [PMID: 34866655 PMCID: PMC8635116 DOI: 10.1088/1361-6463/ac2170] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Mechanical cues have been suggested to play an important role in cell functions and cell fate determination, however, such physical quantities are challenging to directly measure in living cells with single molecule sensitivity and resolution. In this review, we focus on two main technologies that are promising in probing forces at the single molecule level. We review their theoretical fundamentals, recent technical advancements, and future directions, tailored specifically for interrogating mechanosensitive molecules in live cells.
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Affiliation(s)
- Jason Pan
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States of America
| | - Tommy Kmieciak
- Department of Engineering Physics, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States of America
| | - Yen-Ting Liu
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States of America
| | - Matthew Wildenradt
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States of America
| | - Yun-Sheng Chen
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States of America
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States of America
| | - Yang Zhao
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States of America
- Holonyak Micro and Nanotechnology Laboratory, University of Illinois at Urbana-Champaign, 208 N. Wright Street, Urbana, IL 61801, United States of America
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15
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Pandey S, Xiang Y, Friedrich D, Leng Y, Mao H. Direct Measurement of Intermolecular Mechanical Force for Nonspecific Interactions between Small Molecules. J Phys Chem Lett 2021; 12:11316-11322. [PMID: 34780182 PMCID: PMC8778946 DOI: 10.1021/acs.jpclett.1c03142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Mechanical force can evaluate intramolecular interactions in macromolecules. Because of the rapid motion of small molecules, it is extremely challenging to measure mechanical forces of nonspecific intermolecular interactions. Here, we used optical tweezers to directly examine the intermolecular mechanical force (IMMF) of nonspecific interactions between two cholesterols. We found that IMMFs of dimeric cholesterol complexes were dependent on the orientation of the interaction. The surprisingly high IMMF in cholesterol dimers (∼30 pN) is comparable to the mechanical stability of DNA secondary structures. Using Hess-like cycles, we quantified that changes in free energy of solubilizing cholesterol (ΔGsolubility) by β-cyclodextrin (βCD) and methylated βCD (Me-βCD) were as low as -16 and -27 kcal/mol, respectively. Compared to the ΔGsolubility of cholesterols in water (5.1 kcal/mol), these values indicated that cyclodextrins can easily solubilize cholesterols. Our results demonstrated that the IMMF can serve as a generic and multipurpose variable to dissect nonspecific intermolecular interactions among small molecules into orientational components.
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Affiliation(s)
- Shankar Pandey
- Department of Chemistry and Biochemistry, Kent State University, Kent, OH, 44242, USA
| | - Yuan Xiang
- Department of Mechanical and Aerospace Engineering, The George Washington University, Washington, DC 20052, USA
| | - Dirk Friedrich
- Department of Chemistry and Biochemistry, Kent State University, Kent, OH, 44242, USA
| | - Yongsheng Leng
- Department of Mechanical and Aerospace Engineering, The George Washington University, Washington, DC 20052, USA
| | - Hanbin Mao
- Department of Chemistry and Biochemistry, Kent State University, Kent, OH, 44242, USA
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16
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Gomez D, Peña Ccoa WJ, Singh Y, Rojas E, Hocky GM. Molecular Paradigms for Biological Mechanosensing. J Phys Chem B 2021; 125:12115-12124. [PMID: 34709040 DOI: 10.1021/acs.jpcb.1c06330] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Many proteins in living cells are subject to mechanical forces, which can be generated internally by molecular machines, or externally, e.g., by pressure gradients. In general, these forces fall in the piconewton range, which is similar in magnitude to forces experienced by a molecule due to thermal fluctuations. While we would naively expect such moderate forces to produce only minimal changes, a wide variety of "mechanosensing" proteins have evolved with functions that are responsive to forces in this regime. The goal of this article is to provide a physical chemistry perspective on protein-based molecular mechanosensing paradigms used in living systems, and how these paradigms can be explored using novel computational methods.
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Affiliation(s)
- David Gomez
- Department of Biology, New York University, New York, New York 10003, United States.,Department of Chemistry, New York University, New York, New York 10003, United States
| | - Willmor J Peña Ccoa
- Department of Chemistry, New York University, New York, New York 10003, United States
| | - Yuvraj Singh
- Department of Chemistry, New York University, New York, New York 10003, United States
| | - Enrique Rojas
- Department of Biology, New York University, New York, New York 10003, United States
| | - Glen M Hocky
- Department of Chemistry, New York University, New York, New York 10003, United States
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17
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Motz CT, Kabat V, Saxena T, Bellamkonda RV, Zhu C. Neuromechanobiology: An Expanding Field Driven by the Force of Greater Focus. Adv Healthc Mater 2021; 10:e2100102. [PMID: 34342167 PMCID: PMC8497434 DOI: 10.1002/adhm.202100102] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 07/06/2021] [Indexed: 12/14/2022]
Abstract
The brain processes information by transmitting signals through highly connected and dynamic networks of neurons. Neurons use specific cellular structures, including axons, dendrites and synapses, and specific molecules, including cell adhesion molecules, ion channels and chemical receptors to form, maintain and communicate among cells in the networks. These cellular and molecular processes take place in environments rich of mechanical cues, thus offering ample opportunities for mechanical regulation of neural development and function. Recent studies have suggested the importance of mechanical cues and their potential regulatory roles in the development and maintenance of these neuronal structures. Also suggested are the importance of mechanical cues and their potential regulatory roles in the interaction and function of molecules mediating the interneuronal communications. In this review, the current understanding is integrated and promising future directions of neuromechanobiology are suggested at the cellular and molecular levels. Several neuronal processes where mechanics likely plays a role are examined and how forces affect ligand binding, conformational change, and signal induction of molecules key to these neuronal processes are indicated, especially at the synapse. The disease relevance of neuromechanobiology as well as therapies and engineering solutions to neurological disorders stemmed from this emergent field of study are also discussed.
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Affiliation(s)
- Cara T Motz
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
- Parker H. Petit Institute for Bioengineering and Biosciences, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
| | - Victoria Kabat
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
| | - Tarun Saxena
- Department of Biomedical Engineering, Duke University, Durham, NC, 27709, USA
| | - Ravi V Bellamkonda
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, 27708, USA
| | - Cheng Zhu
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
- Parker H. Petit Institute for Bioengineering and Biosciences, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
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18
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Kolb P, Schundner A, Frick M, Gottschalk KE. In Vitro Measurements of Cellular Forces and their Importance in the Lung-From the Sub- to the Multicellular Scale. Life (Basel) 2021; 11:691. [PMID: 34357063 PMCID: PMC8307149 DOI: 10.3390/life11070691] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 07/09/2021] [Accepted: 07/09/2021] [Indexed: 02/07/2023] Open
Abstract
Throughout life, the body is subjected to various mechanical forces on the organ, tissue, and cellular level. Mechanical stimuli are essential for organ development and function. One organ whose function depends on the tightly connected interplay between mechanical cell properties, biochemical signaling, and external forces is the lung. However, altered mechanical properties or excessive mechanical forces can also drive the onset and progression of severe pulmonary diseases. Characterizing the mechanical properties and forces that affect cell and tissue function is therefore necessary for understanding physiological and pathophysiological mechanisms. In recent years, multiple methods have been developed for cellular force measurements at multiple length scales, from subcellular forces to measuring the collective behavior of heterogeneous cellular networks. In this short review, we give a brief overview of the mechanical forces at play on the cellular level in the lung. We then focus on the technological aspects of measuring cellular forces at many length scales. We describe tools with a subcellular resolution and elaborate measurement techniques for collective multicellular units. Many of the technologies described are by no means restricted to lung research and have already been applied successfully to cells from various other tissues. However, integrating the knowledge gained from these multi-scale measurements in a unifying framework is still a major future challenge.
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Affiliation(s)
- Peter Kolb
- Institute of Experimental Physics, Ulm University, 89069 Ulm, Germany;
| | - Annika Schundner
- Institute of General Physiology, Ulm University, 89069 Ulm, Germany;
| | - Manfred Frick
- Institute of General Physiology, Ulm University, 89069 Ulm, Germany;
| | - Kay-E. Gottschalk
- Institute of Experimental Physics, Ulm University, 89069 Ulm, Germany;
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19
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Hang X, He S, Dong Z, Minnick G, Rosenbohm J, Chen Z, Yang R, Chang L. Nanosensors for single cell mechanical interrogation. Biosens Bioelectron 2021; 179:113086. [DOI: 10.1016/j.bios.2021.113086] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 02/07/2021] [Accepted: 02/09/2021] [Indexed: 02/08/2023]
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20
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Fischer LS, Rangarajan S, Sadhanasatish T, Grashoff C. Molecular Force Measurement with Tension Sensors. Annu Rev Biophys 2021; 50:595-616. [PMID: 33710908 DOI: 10.1146/annurev-biophys-101920-064756] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The ability of cells to generate mechanical forces, but also to sense, adapt to, and respond to mechanical signals, is crucial for many developmental, postnatal homeostatic, and pathophysiological processes. However, the molecular mechanisms underlying cellular mechanotransduction have remained elusive for many decades, as techniques to visualize and quantify molecular forces across individual proteins in cells were missing. The development of genetically encoded molecular tension sensors now allows the quantification of piconewton-scale forces that act upon distinct molecules in living cells and even whole organisms. In this review, we discuss the physical principles, advantages, and limitations of this increasingly popular method. By highlighting current examples from the literature, we demonstrate how molecular tension sensors can be utilized to obtain access to previously unappreciated biophysical parameters that define the propagation of mechanical forces on molecular scales. We discuss how the methodology can be further developed and provide a perspective on how the technique could be applied to uncover entirely novel aspects of mechanobiology in the future.
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Affiliation(s)
- Lisa S Fischer
- Department of Quantitative Cell Biology, Institute of Molecular Cell Biology, University of Münster, Münster D-48149, Germany;
| | - Srishti Rangarajan
- Department of Quantitative Cell Biology, Institute of Molecular Cell Biology, University of Münster, Münster D-48149, Germany;
| | - Tanmay Sadhanasatish
- Department of Quantitative Cell Biology, Institute of Molecular Cell Biology, University of Münster, Münster D-48149, Germany;
| | - Carsten Grashoff
- Department of Quantitative Cell Biology, Institute of Molecular Cell Biology, University of Münster, Münster D-48149, Germany;
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21
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Kanoldt V, Kluger C, Barz C, Schweizer AL, Ramanujam D, Windgasse L, Engelhardt S, Chrostek-Grashoff A, Grashoff C. Metavinculin modulates force transduction in cell adhesion sites. Nat Commun 2020; 11:6403. [PMID: 33335089 PMCID: PMC7747745 DOI: 10.1038/s41467-020-20125-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 11/13/2020] [Indexed: 12/15/2022] Open
Abstract
Vinculin is a ubiquitously expressed protein, crucial for the regulation of force transduction in cells. Muscle cells express a vinculin splice-isoform called metavinculin, which has been associated with cardiomyopathies. However, the molecular function of metavinculin has remained unclear and its role for heart muscle disorders undefined. Here, we have employed a set of piconewton-sensitive tension sensors to probe metavinculin mechanics in cells. Our experiments reveal that metavinculin bears higher molecular forces but is less frequently engaged as compared to vinculin, leading to altered force propagation in cell adhesions. In addition, we have generated knockout mice to investigate the consequences of metavinculin loss in vivo. Unexpectedly, these animals display an unaltered tissue response in a cardiac hypertrophy model. Together, the data reveal that the transduction of cell adhesion forces is modulated by expression of metavinculin, yet its role for heart muscle function seems more subtle than previously thought.
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Affiliation(s)
- Verena Kanoldt
- Department of Quantitative Cell Biology, Institute of Molecular Cell Biology, University of Münster, 48149, Münster, Germany
- Max Planck Institute of Biochemistry, Group of Molecular Mechanotransduction, 82152, Martinsried, Germany
| | - Carleen Kluger
- Max Planck Institute of Biochemistry, Group of Molecular Mechanotransduction, 82152, Martinsried, Germany
| | - Christiane Barz
- Max Planck Institute of Biochemistry, Group of Molecular Mechanotransduction, 82152, Martinsried, Germany
| | - Anna-Lena Schweizer
- Department of Quantitative Cell Biology, Institute of Molecular Cell Biology, University of Münster, 48149, Münster, Germany
- Max Planck Institute of Biochemistry, Group of Molecular Mechanotransduction, 82152, Martinsried, Germany
| | - Deepak Ramanujam
- Institute of Pharmacology and Toxicology, Technical University of Munich, 80802, Munich, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Munich Heart Alliance, 80802, Munich, Germany
| | - Lukas Windgasse
- Department of Quantitative Cell Biology, Institute of Molecular Cell Biology, University of Münster, 48149, Münster, Germany
| | - Stefan Engelhardt
- Institute of Pharmacology and Toxicology, Technical University of Munich, 80802, Munich, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Munich Heart Alliance, 80802, Munich, Germany
| | - Anna Chrostek-Grashoff
- Department of Quantitative Cell Biology, Institute of Molecular Cell Biology, University of Münster, 48149, Münster, Germany
- Max Planck Institute of Biochemistry, Group of Molecular Mechanotransduction, 82152, Martinsried, Germany
| | - Carsten Grashoff
- Department of Quantitative Cell Biology, Institute of Molecular Cell Biology, University of Münster, 48149, Münster, Germany.
- Max Planck Institute of Biochemistry, Group of Molecular Mechanotransduction, 82152, Martinsried, Germany.
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22
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An insight on Drosophila myogenesis and its assessment techniques. Mol Biol Rep 2020; 47:9849-9863. [PMID: 33263930 DOI: 10.1007/s11033-020-06006-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 11/16/2020] [Indexed: 10/22/2022]
Abstract
Movement assisted by muscles forms the basis of various behavioural traits seen in Drosophila. Myogenesis involves developmental processes like cellular specification, differentiation, migration, fusion, adherence to tendons and neuronal innervation in a series of coordinated event well defined in body space and time. Gene regulatory networks are switched on-off, fine tuning at the right developmental stage to assist each cellular event. Drosophila is a holometabolous organism that undergoes myogenesis waves at two developmental stages, and is ideal for comparative analysis of the role of genes and genetic pathways conserved across phyla. In this review we have summarized myogenic events from the embryo to adult focussing on the somatic muscle development during the early embryonic stage and then on indirect flight muscles (IFM) formation required for adult life, emphasizing on recent trends of analysing muscle mutants and advances in Drosophila muscle biology.
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23
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Belardi B, Son S, Felce JH, Dustin ML, Fletcher DA. Cell-cell interfaces as specialized compartments directing cell function. Nat Rev Mol Cell Biol 2020; 21:750-764. [PMID: 33093672 DOI: 10.1038/s41580-020-00298-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/09/2020] [Indexed: 12/14/2022]
Abstract
Cell-cell interfaces are found throughout multicellular organisms, from transient interactions between motile immune cells to long-lived cell-cell contacts in epithelia. Studies of immune cell interactions, epithelial cell barriers, neuronal contacts and sites of cell-cell fusion have identified a core set of features shared by cell-cell interfaces that critically control their function. Data from diverse cell types also show that cells actively and passively regulate the localization, strength, duration and cytoskeletal coupling of receptor interactions governing cell-cell signalling and physical connections between cells, indicating that cell-cell interfaces have a unique membrane organization that emerges from local molecular and cellular mechanics. In this Review, we discuss recent findings that support the emerging view of cell-cell interfaces as specialized compartments that biophysically constrain the arrangement and activity of their protein, lipid and glycan components. We also review how these biophysical features of cell-cell interfaces allow cells to respond with high selectivity and sensitivity to multiple inputs, serving as the basis for wide-ranging cellular functions. Finally, we consider how the unique properties of cell-cell interfaces present opportunities for therapeutic intervention.
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Affiliation(s)
- Brian Belardi
- Department of Bioengineering & Biophysics Program, UC Berkeley, Berkeley, CA, USA
| | - Sungmin Son
- Department of Bioengineering & Biophysics Program, UC Berkeley, Berkeley, CA, USA
| | | | | | - Daniel A Fletcher
- Department of Bioengineering & Biophysics Program, UC Berkeley, Berkeley, CA, USA. .,Division of Biological Systems & Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA, USA. .,Chan Zuckerberg Biohub, San Francisco, CA, USA.
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24
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Saqr KM, Tupin S, Rashad S, Endo T, Niizuma K, Tominaga T, Ohta M. Physiologic blood flow is turbulent. Sci Rep 2020; 10:15492. [PMID: 32968087 PMCID: PMC7512016 DOI: 10.1038/s41598-020-72309-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 08/27/2020] [Indexed: 12/18/2022] Open
Abstract
Contemporary paradigm of peripheral and intracranial vascular hemodynamics considers physiologic blood flow to be laminar. Transition to turbulence is considered as a driving factor for numerous diseases such as atherosclerosis, stenosis and aneurysm. Recently, turbulent flow patterns were detected in intracranial aneurysm at Reynolds number below 400 both in vitro and in silico. Blood flow is multiharmonic with considerable frequency spectra and its transition to turbulence cannot be characterized by the current transition theory of monoharmonic pulsatile flow. Thus, we decided to explore the origins of such long-standing assumption of physiologic blood flow laminarity. Here, we hypothesize that the inherited dynamics of blood flow in main arteries dictate the existence of turbulence in physiologic conditions. To illustrate our hypothesis, we have used methods and tools from chaos theory, hydrodynamic stability theory and fluid dynamics to explore the existence of turbulence in physiologic blood flow. Our investigation shows that blood flow, both as described by the Navier–Stokes equation and in vivo, exhibits three major characteristics of turbulence. Womersley’s exact solution of the Navier–Stokes equation has been used with the flow waveforms from HaeMod database, to offer reproducible evidence for our findings, as well as evidence from Doppler ultrasound measurements from healthy volunteers who are some of the authors. We evidently show that physiologic blood flow is: (1) sensitive to initial conditions, (2) in global hydrodynamic instability and (3) undergoes kinetic energy cascade of non-Kolmogorov type. We propose a novel modification of the theory of vascular hemodynamics that calls for rethinking the hemodynamic–biologic links that govern physiologic and pathologic processes.
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Affiliation(s)
- Khalid M Saqr
- Biomedical Flow Dynamics Laboratory (Ohta-Lab), Institute of Fluid Science, Tohoku University, Sendai, Miyagi, 980-8577, Japan.
| | - Simon Tupin
- Biomedical Flow Dynamics Laboratory (Ohta-Lab), Institute of Fluid Science, Tohoku University, Sendai, Miyagi, 980-8577, Japan
| | - Sherif Rashad
- Department of Neurosurgical Engineering and Translational Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Miyagi, 980-8574, Japan.,Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, 980-8574, Japan
| | - Toshiki Endo
- Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, 980-8574, Japan
| | - Kuniyasu Niizuma
- Department of Neurosurgical Engineering and Translational Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Miyagi, 980-8574, Japan.,Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, 980-8574, Japan.,Department of Neurosurgical Engineering and Translational Neuroscience, Graduate School of Biomedical Engineering, Tohoku University, Sendai, Miyagi, 980-8574, Japan
| | - Teiji Tominaga
- Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, 980-8574, Japan
| | - Makoto Ohta
- Biomedical Flow Dynamics Laboratory (Ohta-Lab), Institute of Fluid Science, Tohoku University, Sendai, Miyagi, 980-8577, Japan
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25
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Hartmann MJ, Singh Y, Vanden-Eijnden E, Hocky GM. Infinite switch simulated tempering in force (FISST). J Chem Phys 2020; 152:244120. [DOI: 10.1063/5.0009280] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Affiliation(s)
| | - Yuvraj Singh
- Department of Chemistry, New York University, New York, New York 10003, USA
| | - Eric Vanden-Eijnden
- Courant Institute of Mathematical Sciences, New York University, New York, New York 10012, USA
| | - Glen M. Hocky
- Department of Chemistry, New York University, New York, New York 10003, USA
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26
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Baillie AL, Falz AL, Müller-Schüssele SJ, Sparkes I. It Started With a Kiss: Monitoring Organelle Interactions and Identifying Membrane Contact Site Components in Plants. FRONTIERS IN PLANT SCIENCE 2020; 11:517. [PMID: 32435254 PMCID: PMC7218140 DOI: 10.3389/fpls.2020.00517] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 04/06/2020] [Indexed: 05/10/2023]
Abstract
Organelle movement and interaction are dynamic processes. Interpreting the functional role and mechanistic detail of interactions at membrane contact sites requires careful quantification of parameters such as duration, frequency, proximity, and surface area of contact, and identification of molecular components. We provide an overview of current methods used to quantify organelle interactions in plants and other organisms and propose novel applications of existing technologies to tackle this emerging topic in plant cell biology.
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Affiliation(s)
- Alice L. Baillie
- School of Biological Sciences, University of Bristol, Bristol, United Kingdom
| | - Anna-Lena Falz
- Institut für Nutzpflanzenforschung und Ressourcenschutz (INRES), Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| | - Stefanie J. Müller-Schüssele
- Institut für Nutzpflanzenforschung und Ressourcenschutz (INRES), Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| | - Imogen Sparkes
- School of Biological Sciences, University of Bristol, Bristol, United Kingdom
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27
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Rivas-Pardo JA, Li Y, Mártonfalvi Z, Tapia-Rojo R, Unger A, Fernández-Trasancos Á, Herrero-Galán E, Velázquez-Carreras D, Fernández JM, Linke WA, Alegre-Cebollada J. A HaloTag-TEV genetic cassette for mechanical phenotyping of proteins from tissues. Nat Commun 2020; 11:2060. [PMID: 32345978 PMCID: PMC7189229 DOI: 10.1038/s41467-020-15465-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Accepted: 03/09/2020] [Indexed: 11/09/2022] Open
Abstract
Single-molecule methods using recombinant proteins have generated transformative hypotheses on how mechanical forces are generated and sensed in biological tissues. However, testing these mechanical hypotheses on proteins in their natural environment remains inaccesible to conventional tools. To address this limitation, here we demonstrate a mouse model carrying a HaloTag-TEV insertion in the protein titin, the main determinant of myocyte stiffness. Using our system, we specifically sever titin by digestion with TEV protease, and find that the response of muscle fibers to length changes requires mechanical transduction through titin's intact polypeptide chain. In addition, HaloTag-based covalent tethering enables examination of titin dynamics under force using magnetic tweezers. At pulling forces < 10 pN, titin domains are recruited to the unfolded state, and produce 41.5 zJ mechanical work during refolding. Insertion of the HaloTag-TEV cassette in mechanical proteins opens opportunities to explore the molecular basis of cellular force generation, mechanosensing and mechanotransduction.
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Affiliation(s)
- Jaime Andrés Rivas-Pardo
- Department of Biological Sciences, Columbia University, New York, NY, 10027, USA
- Center for Genomics and Bioinformatics, Facultad de Ciencias, Universidad Mayor, Santiago, Chile
| | - Yong Li
- Institute of Physiology II, University of Muenster, Muenster, Germany
| | - Zsolt Mártonfalvi
- Department of Biophysics and Radiation Biology, Semmelweis University, Budapest, Hungary
| | - Rafael Tapia-Rojo
- Department of Biological Sciences, Columbia University, New York, NY, 10027, USA
| | - Andreas Unger
- Institute of Physiology II, University of Muenster, Muenster, Germany
| | | | | | | | - Julio M Fernández
- Department of Biological Sciences, Columbia University, New York, NY, 10027, USA
| | - Wolfgang A Linke
- Institute of Physiology II, University of Muenster, Muenster, Germany.
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28
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Zhang K, Oldenhof S, Wang Y, Esch JH, Mendes E. Spatial Manipulation and Integration of Supramolecular Filaments on Hydrogel Substrates towards Advanced Soft Devices. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201915100] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Kai Zhang
- Department of Chemical Engineering Deflt University of Technology van der Maasweg 9 2629 HZ Delft The Netherlands
| | - Sander Oldenhof
- Department of Chemical Engineering Deflt University of Technology van der Maasweg 9 2629 HZ Delft The Netherlands
- Netherlands Forensic Institute Laan van Ypenburg 6 2497 GB Den Haag The Netherlands
| | - Yiming Wang
- Department of Chemical Engineering Deflt University of Technology van der Maasweg 9 2629 HZ Delft The Netherlands
- State Key Laboratory of Chemical Engineering East China University of Science and Technology Meilong Road 130 200237 Shanghai China
| | - Jan H. Esch
- Department of Chemical Engineering Deflt University of Technology van der Maasweg 9 2629 HZ Delft The Netherlands
| | - Eduardo Mendes
- Department of Chemical Engineering Deflt University of Technology van der Maasweg 9 2629 HZ Delft The Netherlands
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Zhang K, Oldenhof S, Wang Y, Esch JH, Mendes E. Spatial Manipulation and Integration of Supramolecular Filaments on Hydrogel Substrates towards Advanced Soft Devices. Angew Chem Int Ed Engl 2020; 59:8601-8607. [DOI: 10.1002/anie.201915100] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Indexed: 02/03/2023]
Affiliation(s)
- Kai Zhang
- Department of Chemical Engineering Deflt University of Technology van der Maasweg 9 2629 HZ Delft The Netherlands
| | - Sander Oldenhof
- Department of Chemical Engineering Deflt University of Technology van der Maasweg 9 2629 HZ Delft The Netherlands
- Netherlands Forensic Institute Laan van Ypenburg 6 2497 GB Den Haag The Netherlands
| | - Yiming Wang
- Department of Chemical Engineering Deflt University of Technology van der Maasweg 9 2629 HZ Delft The Netherlands
- State Key Laboratory of Chemical Engineering East China University of Science and Technology Meilong Road 130 200237 Shanghai China
| | - Jan H. Esch
- Department of Chemical Engineering Deflt University of Technology van der Maasweg 9 2629 HZ Delft The Netherlands
| | - Eduardo Mendes
- Department of Chemical Engineering Deflt University of Technology van der Maasweg 9 2629 HZ Delft The Netherlands
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30
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Aird EJ, Tompkins KJ, Ramirez MP, Gordon WR. Enhanced Molecular Tension Sensor Based on Bioluminescence Resonance Energy Transfer (BRET). ACS Sens 2020; 5:34-39. [PMID: 31872754 DOI: 10.1021/acssensors.9b00796] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Molecular tension sensors measure piconewton forces experienced by individual proteins in the context of the cellular microenvironment. Current genetically encoded tension sensors use FRET to report on extension of a deformable peptide encoded in a cellular protein of interest. Here, we present the development and characterization of a new type of molecular tension sensor based on bioluminescence resonance energy transfer (BRET), which exhibits more desirable spectral properties and an enhanced dynamic range compared to other molecular tension sensors. Moreover, it avoids many disadvantages of FRET measurements in cells, including autofluorescence, photobleaching, and corrections of direct acceptor excitation. We benchmark the sensor by inserting it into the canonical mechanosensing focal adhesion protein vinculin, observing highly resolved gradients of tensional changes across focal adhesions. We anticipate that the BRET tension sensor will expand the toolkit available to study mechanotransduction at a molecular level and allow potential extension to an in vivo context.
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Affiliation(s)
- Eric J. Aird
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Kassidy J. Tompkins
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Maria Paz Ramirez
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Wendy R. Gordon
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, United States
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31
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Zhang J, Chada NC, Reinhart-King CA. Microscale Interrogation of 3D Tissue Mechanics. Front Bioeng Biotechnol 2019; 7:412. [PMID: 31921816 PMCID: PMC6927918 DOI: 10.3389/fbioe.2019.00412] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Accepted: 11/28/2019] [Indexed: 01/02/2023] Open
Abstract
Cells in vivo live in a complex microenvironment composed of the extracellular matrix (ECM) and other cells. Growing evidence suggests that the mechanical interaction between the cells and their microenvironment is of critical importance to their behaviors under both normal and diseased conditions, such as migration, differentiation, and proliferation. The study of tissue mechanics in the past two decades, including the assessment of both mechanical properties and mechanical stresses of the extracellular microenvironment, has greatly enriched our knowledge about how cells interact with their mechanical environment. Tissue mechanical properties are often heterogeneous and sometimes anisotropic, which makes them difficult to obtain from macroscale bulk measurements. Mechanical stresses were first measured for cells cultured on two-dimensional (2D) surfaces with well-defined mechanical properties. While 2D measurements are relatively straightforward and efficient, and they have provided us with valuable knowledge on cell-ECM interactions, that knowledge may not be directly applicable to in vivo systems. Hence, the measurement of tissue stresses in a more physiologically relevant three-dimensional (3D) environment is required. In this mini review, we will summarize and discuss recent developments in using optical, magnetic, genetic, and mechanical approaches to interrogate 3D tissue stresses and mechanical properties at the microscale.
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Ham TR, Collins KL, Hoffman BD. Molecular Tension Sensors: Moving Beyond Force. CURRENT OPINION IN BIOMEDICAL ENGINEERING 2019; 12:83-94. [PMID: 32864525 DOI: 10.1016/j.cobme.2019.10.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Nearly all cellular processes are sensitive to mechanical inputs, and this plays a major role in diverse physiological processes. Mechanical stimuli are thought to be primarily detected through force-induced changes in protein structure. Approximately a decade ago, molecular tension sensors were created to measure forces across proteins within cells. Since then, an impressive assortment of sensors has been created and provided key insights into mechanotransduction, but comparisons of measurements between various sensors are challenging. In this review, we discuss the different types of molecular tension sensors, provide a system of classification based on their molecular-scale mechanical properties, and highlight how new applications of these sensors are enabling measurements beyond the magnitude of tensile load. We suggest that an expanded understanding of the functionality of these sensors, as well as integration with other techniques, will lead to consensus amongst measurements as well as critical insights into the underlying mechanisms of mechanotransduction.
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Affiliation(s)
- Trevor R Ham
- Duke University, Room 1379 CIEMAS, 101 Science Drive, 27710, United States
| | - Kasie L Collins
- Duke University, Room 1379 CIEMAS, 101 Science Drive, 27710, United States
| | - Brenton D Hoffman
- Duke University, Room 1379 CIEMAS, 101 Science Drive, 27710, United States
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Skruzny M, Pohl E, Abella M. FRET Microscopy in Yeast. BIOSENSORS 2019; 9:E122. [PMID: 31614546 PMCID: PMC6956097 DOI: 10.3390/bios9040122] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 09/19/2019] [Accepted: 09/30/2019] [Indexed: 02/06/2023]
Abstract
Förster resonance energy transfer (FRET) microscopy is a powerful fluorescence microscopy method to study the nanoscale organization of multiprotein assemblies in vivo. Moreover, many biochemical and biophysical processes can be followed by employing sophisticated FRET biosensors directly in living cells. Here, we summarize existing FRET experiments and biosensors applied in yeasts Saccharomyces cerevisiae and Schizosaccharomyces pombe, two important models of fundamental biomedical research and efficient platforms for analyses of bioactive molecules. We aim to provide a practical guide on suitable FRET techniques, fluorescent proteins, and experimental setups available for successful FRET experiments in yeasts.
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Affiliation(s)
- Michal Skruzny
- Department of Systems and Synthetic Microbiology, Max Planck Institute for Terrestrial Microbiology, 35043 Marburg, Germany.
- LOEWE Center for Synthetic Microbiology (SYNMIKRO), 35043 Marburg, Germany.
| | - Emma Pohl
- Department of Systems and Synthetic Microbiology, Max Planck Institute for Terrestrial Microbiology, 35043 Marburg, Germany
- LOEWE Center for Synthetic Microbiology (SYNMIKRO), 35043 Marburg, Germany
| | - Marc Abella
- Department of Systems and Synthetic Microbiology, Max Planck Institute for Terrestrial Microbiology, 35043 Marburg, Germany
- LOEWE Center for Synthetic Microbiology (SYNMIKRO), 35043 Marburg, Germany
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34
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Zuela-Sopilniak N, Lammerding J. Engineering approaches to studying cancer cell migration in three-dimensional environments. Philos Trans R Soc Lond B Biol Sci 2019; 374:20180219. [PMID: 31431175 PMCID: PMC6627017 DOI: 10.1098/rstb.2018.0219] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/15/2019] [Indexed: 12/24/2022] Open
Abstract
Cancer is one of the most devastating diseases of our time, with 17 million new cancer cases and 9.5 million cancer deaths in 2018 worldwide. The mortality associated with cancer results primarily from metastasis, i.e. the spreading of cancer cells from the primary tumour to other organs. The invasion and migration of cells through basement membranes, tight interstitial spaces and endothelial cell layers are key steps in the metastatic cascade. Recent studies demonstrated that cell migration through three-dimensional environments that mimic the in vivo conditions significantly differs from their migration on two-dimensional surfaces. Here, we review recent technological advances made in the field of cancer research that provide more 'true to the source' experimental platforms and measurements for the study of cancer cell invasion and migration in three-dimensional environments. These include microfabrication, three-dimensional bioprinting and intravital imaging tools, along with force and stiffness measurements of cells and their environments. These techniques will enable new studies that better reflect the physiological environment found in vivo, thereby producing more robust results. The knowledge achieved through these studies will aid in the development of new treatment options with the potential to ultimately lighten the devastating cost cancer inflicts on patients and their families. This article is part of a discussion meeting issue 'Forces in cancer: interdisciplinary approaches in tumour mechanobiology'.
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Affiliation(s)
| | - Jan Lammerding
- Nancy E. and Peter C. Meinig School of Biomedical Engineering, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
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35
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Feng Q, Lee SS, Kornmann B. A Toolbox for Organelle Mechanobiology Research-Current Needs and Challenges. MICROMACHINES 2019; 10:E538. [PMID: 31426349 PMCID: PMC6723503 DOI: 10.3390/mi10080538] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 08/04/2019] [Accepted: 08/09/2019] [Indexed: 02/07/2023]
Abstract
Mechanobiology studies from the last decades have brought significant insights into many domains of biological research, from development to cellular signaling. However, mechano-regulation of subcellular components, especially membranous organelles, are only beginning to be unraveled. In this paper, we take mitochondrial mechanobiology as an example to discuss recent advances and current technical challenges in this field. In addition, we discuss the needs for future toolbox development for mechanobiological research of intracellular organelles.
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Affiliation(s)
- Qian Feng
- Institute of Biochemistry, ETH Zurich, 8093 Zurich, Switzerland.
- Institute of Molecular Health Sciences, ETH Zurich, 8093 Zurich, Switzerland.
| | - Sung Sik Lee
- Institute of Biochemistry, ETH Zurich, 8093 Zurich, Switzerland.
- Scientific Center for Optical and Electron Microscopy (ScopeM), ETH Zurich, 8093 Zurich, Switzerland.
| | - Benoît Kornmann
- Institute of Biochemistry, ETH Zurich, 8093 Zurich, Switzerland
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK
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36
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Eckels EC, Tapia-Rojo R, Rivas-Pardo JA, Fernández JM. The Work of Titin Protein Folding as a Major Driver in Muscle Contraction. Annu Rev Physiol 2019; 80:327-351. [PMID: 29433413 DOI: 10.1146/annurev-physiol-021317-121254] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Single-molecule atomic force microscopy and magnetic tweezers experiments have demonstrated that titin immunoglobulin (Ig) domains are capable of folding against a pulling force, generating mechanical work that exceeds that produced by a myosin motor. We hypothesize that upon muscle activation, formation of actomyosin cross bridges reduces the force on titin, causing entropic recoil of the titin polymer and triggering the folding of the titin Ig domains. In the physiological force range of 4-15 pN under which titin operates in muscle, the folding contraction of a single Ig domain can generate 200% of the work of entropic recoil and occurs at forces that exceed the maximum stalling force of single myosin motors. Thus, titin operates like a mechanical battery, storing elastic energy efficiently by unfolding Ig domains and delivering the charge back by folding when the motors are activated during a contraction. We advance the hypothesis that titin folding and myosin activation act as inextricable partners during muscle contraction.
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Affiliation(s)
- Edward C Eckels
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA; , .,Integrated Program in Cellular, Molecular, and Biomedical Studies, Columbia University Medical Center, New York, NY 10032, USA
| | - Rafael Tapia-Rojo
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA; ,
| | | | - Julio M Fernández
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA; ,
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37
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Lemke SB, Weidemann T, Cost AL, Grashoff C, Schnorrer F. A small proportion of Talin molecules transmit forces at developing muscle attachments in vivo. PLoS Biol 2019; 17:e3000057. [PMID: 30917109 PMCID: PMC6453563 DOI: 10.1371/journal.pbio.3000057] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 04/08/2019] [Accepted: 03/08/2019] [Indexed: 11/19/2022] Open
Abstract
Cells in developing organisms are subjected to particular mechanical forces that shape tissues and instruct cell fate decisions. How these forces are sensed and transmitted at the molecular level is therefore an important question, one that has mainly been investigated in cultured cells in vitro. Here, we elucidate how mechanical forces are transmitted in an intact organism. We studied Drosophila muscle attachment sites, which experience high mechanical forces during development and require integrin-mediated adhesion for stable attachment to tendons. Therefore, we quantified molecular forces across the essential integrin-binding protein Talin, which links integrin to the actin cytoskeleton. Generating flies expressing 3 Förster resonance energy transfer (FRET)-based Talin tension sensors reporting different force levels between 1 and 11 piconewton (pN) enabled us to quantify physiologically relevant molecular forces. By measuring primary Drosophila muscle cells, we demonstrate that Drosophila Talin experiences mechanical forces in cell culture that are similar to those previously reported for Talin in mammalian cell lines. However, in vivo force measurements at developing flight muscle attachment sites revealed that average forces across Talin are comparatively low and decrease even further while attachments mature and tissue-level tension remains high. Concomitantly, the Talin concentration at attachment sites increases 5-fold as quantified by fluorescence correlation spectroscopy (FCS), suggesting that only a small proportion of Talin molecules are mechanically engaged at any given time. Reducing Talin levels at late stages of muscle development results in muscle–tendon rupture in the adult fly, likely as a result of active muscle contractions. We therefore propose that a large pool of adhesion molecules is required to share high tissue forces. As a result, less than 15% of the molecules experience detectable forces at developing muscle attachment sites at the same time. Our findings define an important new concept of how cells can adapt to changes in tissue mechanics to prevent mechanical failure in vivo. The protein Talin links the transmembrane cell adhesion molecule integrin to the actin cytoskeleton. Quantitative FRET-based force measurements across Talin in vivo reveal that only few Talin molecules are under force during the development of muscle attachment sites. Cells in our body are constantly exposed to mechanical forces, which they need to sense and react to. In previous studies, fluorescent force sensors were developed to demonstrate that individual proteins in adhesion structures of a cell experience forces in the piconewton (pN) range. However, these cells were analyzed in isolation in an artificial plastic or glass environment. Here, we explored forces on adhesion proteins in their natural environment within a developing animal and used the muscle–tendon tissue in the fruit fly Drosophila as a model system. We made genetically modified fly lines with force sensors or controls inserted into the gene that produces the essential adhesion protein Talin. Using these force sensor flies, we found that only a small proportion of all the Talin proteins (<15%) present at developing muscle–tendon attachments experience detectable forces at the same time. Nevertheless, a large amount of Talin is accumulated at these attachments during fly development. We found that this large Talin pool is important to prevent rupture of the muscle–tendon connection in adult flies that produce high muscle forces during flight. In conclusion, we demonstrated that a large pool of Talin proteins is required for stable muscle–tendon attachment, likely with the individual Talin molecules dynamically sharing the mechanical load.
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Affiliation(s)
- Sandra B. Lemke
- Max Planck Institute of Biochemistry, Martinsried, Germany
- * E-mail: (FS); (CG); (SBL)
| | | | - Anna-Lena Cost
- Max Planck Institute of Biochemistry, Martinsried, Germany
- University of Münster, Institute for Molecular Cell Biology, Münster, Germany
| | - Carsten Grashoff
- Max Planck Institute of Biochemistry, Martinsried, Germany
- University of Münster, Institute for Molecular Cell Biology, Münster, Germany
- * E-mail: (FS); (CG); (SBL)
| | - Frank Schnorrer
- Max Planck Institute of Biochemistry, Martinsried, Germany
- Aix Marseille University, CNRS, IBDM, Marseille, France
- * E-mail: (FS); (CG); (SBL)
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38
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Cost A, Khalaji S, Grashoff C. Genetically Encoded FRET‐Based Tension Sensors. ACTA ACUST UNITED AC 2019; 83:e85. [DOI: 10.1002/cpcb.85] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Anna‐Lena Cost
- Group of Molecular Mechanotransduction, Max Planck Institute of Biochemistry Martinsried Germany
- Department of Quantitative Cell Biology, Institute of Molecular Cell BiologyUniversity of Münster Münster Germany
| | - Samira Khalaji
- Group of Molecular Mechanotransduction, Max Planck Institute of Biochemistry Martinsried Germany
- Department of Quantitative Cell Biology, Institute of Molecular Cell BiologyUniversity of Münster Münster Germany
| | - Carsten Grashoff
- Group of Molecular Mechanotransduction, Max Planck Institute of Biochemistry Martinsried Germany
- Department of Quantitative Cell Biology, Institute of Molecular Cell BiologyUniversity of Münster Münster Germany
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39
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Greenwald EC, Mehta S, Zhang J. Genetically Encoded Fluorescent Biosensors Illuminate the Spatiotemporal Regulation of Signaling Networks. Chem Rev 2018; 118:11707-11794. [PMID: 30550275 PMCID: PMC7462118 DOI: 10.1021/acs.chemrev.8b00333] [Citation(s) in RCA: 302] [Impact Index Per Article: 50.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Cellular signaling networks are the foundation which determines the fate and function of cells as they respond to various cues and stimuli. The discovery of fluorescent proteins over 25 years ago enabled the development of a diverse array of genetically encodable fluorescent biosensors that are capable of measuring the spatiotemporal dynamics of signal transduction pathways in live cells. In an effort to encapsulate the breadth over which fluorescent biosensors have expanded, we endeavored to assemble a comprehensive list of published engineered biosensors, and we discuss many of the molecular designs utilized in their development. Then, we review how the high temporal and spatial resolution afforded by fluorescent biosensors has aided our understanding of the spatiotemporal regulation of signaling networks at the cellular and subcellular level. Finally, we highlight some emerging areas of research in both biosensor design and applications that are on the forefront of biosensor development.
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Affiliation(s)
- Eric C Greenwald
- University of California , San Diego, 9500 Gilman Drive, BRFII , La Jolla , CA 92093-0702 , United States
| | - Sohum Mehta
- University of California , San Diego, 9500 Gilman Drive, BRFII , La Jolla , CA 92093-0702 , United States
| | - Jin Zhang
- University of California , San Diego, 9500 Gilman Drive, BRFII , La Jolla , CA 92093-0702 , United States
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40
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Gates EM, LaCroix AS, Rothenberg KE, Hoffman BD. Improving Quality, Reproducibility, and Usability of FRET-Based Tension Sensors. Cytometry A 2018; 95:201-213. [PMID: 30523675 DOI: 10.1002/cyto.a.23688] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 10/30/2018] [Accepted: 11/05/2018] [Indexed: 02/07/2023]
Abstract
Mechanobiology, the study of how mechanical forces affect cellular behavior, is an emerging field of study that has garnered broad and significant interest. Researchers are currently seeking to better understand how mechanical signals are transmitted, detected, and integrated at a subcellular level. One tool for addressing these questions is a Förster resonance energy transfer (FRET)-based tension sensor, which enables the measurement of molecular-scale forces across proteins based on changes in emitted light. However, the reliability and reproducibility of measurements made with these sensors has not been thoroughly examined. To address these concerns, we developed numerical methods that improve the accuracy of measurements made using sensitized emission-based imaging. To establish that FRET-based tension sensors are versatile tools that provide consistent measurements, we used these methods, and demonstrated that a vinculin tension sensor is unperturbed by cell fixation, permeabilization, and immunolabeling. This suggests FRET-based tension sensors could be coupled with a variety of immuno-fluorescent labeling techniques. Additionally, as tension sensors are frequently employed in complex biological samples where large experimental repeats may be challenging, we examined how sample size affects the uncertainty of FRET measurements. In total, this work establishes guidelines to improve FRET-based tension sensor measurements, validate novel implementations of these sensors, and ensure that results are precise and reproducible. © 2018 International Society for Advancement of Cytometry.
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Affiliation(s)
- Evan M Gates
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, 27708
| | - Andrew S LaCroix
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, 27708
| | - Katheryn E Rothenberg
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, 27708
| | - Brenton D Hoffman
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, 27708
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41
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Teunissen AJP, Pérez-Medina C, Meijerink A, Mulder WJM. Investigating supramolecular systems using Förster resonance energy transfer. Chem Soc Rev 2018; 47:7027-7044. [PMID: 30091770 PMCID: PMC6441672 DOI: 10.1039/c8cs00278a] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Supramolecular systems have applications in areas as diverse as materials science, biochemistry, analytical chemistry, and nanomedicine. However, analyzing such systems can be challenging due to the wide range of time scales, binding strengths, distances, and concentrations at which non-covalent phenomena take place. Due to their versatility and sensitivity, Förster resonance energy transfer (FRET)-based techniques are excellently suited to meet such challenges. Here, we detail the ways in which FRET has been used to study non-covalent interactions in both synthetic and biological supramolecular systems. Among other topics, we examine methods to measure molecular forces, determine protein conformations, monitor assembly kinetics, and visualize in vivo drug release from nanoparticles. Furthermore, we highlight multiplex FRET techniques, discuss the field's limitations, and provide a perspective on new developments.
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Affiliation(s)
- Abraham J. P. Teunissen
- Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, New York, NY 10029, USA
| | - Carlos Pérez-Medina
- Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, New York, NY 10029, USA
| | - Andries Meijerink
- Department of Chemistry, Utrecht University, Princetonplein 1, 3584 CC Utrecht, The Netherlands
| | - Willem J. M. Mulder
- Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, New York, NY 10029, USA
- Department of Medical Biochemistry, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
- Laboratory of Chemical biology, Department of Biomedical Engineering and Institute for Complex Molecular systems, Eindhoven University of Technology, P.O. Box 513, 5600 MB, The Netherlands
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42
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Yap AS, Duszyc K, Viasnoff V. Mechanosensing and Mechanotransduction at Cell-Cell Junctions. Cold Spring Harb Perspect Biol 2018; 10:cshperspect.a028761. [PMID: 28778874 DOI: 10.1101/cshperspect.a028761] [Citation(s) in RCA: 93] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Cell adhesion systems are defined by their ability to resist detachment force. Our understanding of the biology of cell-cell adhesions has recently been transformed by the realization that many of the forces that act on those adhesions are generated by the cells that they couple together; and that force at adhesive junctions can be sensed to regulate cell behavior. Here, we consider the mechanisms responsible for applying force to cell-cell junctions and the mechanosensory pathways that detect those forces. We focus on cadherins, as these are the best-studied examples to date, but it is likely that similar principles will apply to other molecular systems that can engage with force-generators within cells and physically couple those cells together.
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Affiliation(s)
- Alpha S Yap
- Institute for Molecular Bioscience, Division of Cell Biology and Molecular Medicine, The University of Queensland, St. Lucia, Brisbane 4072, Australia
| | - Kinga Duszyc
- Institute for Molecular Bioscience, Division of Cell Biology and Molecular Medicine, The University of Queensland, St. Lucia, Brisbane 4072, Australia
| | - Virgile Viasnoff
- Mechanobiology Institute, National University of Singapore, Singapore 117411.,CNRS, Singapore 117411
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LaCroix AS, Lynch AD, Berginski ME, Hoffman BD. Tunable molecular tension sensors reveal extension-based control of vinculin loading. eLife 2018; 7:33927. [PMID: 30024378 PMCID: PMC6053308 DOI: 10.7554/elife.33927] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 06/03/2018] [Indexed: 01/03/2023] Open
Abstract
Molecular tension sensors have contributed to a growing understanding of mechanobiology. However, the limited dynamic range and inability to specify the mechanical sensitivity of these sensors has hindered their widespread use in diverse contexts. Here, we systematically examine the components of tension sensors that can be altered to improve their functionality. Guided by the development of a first principles model describing the mechanical behavior of these sensors, we create a collection of sensors that exhibit predictable sensitivities and significantly improved performance in cellulo. Utilized in the context of vinculin mechanobiology, a trio of these new biosensors with distinct force- and extension-sensitivities reveal that an extension-based control paradigm regulates vinculin loading in a variety of mechanical contexts. To enable the rational design of molecular tension sensors appropriate for diverse applications, we predict the mechanical behavior, in terms of force and extension, of additional 1020 distinct designs. Cells must sense signals from their surroundings to play their roles within the body. These signals can be biochemical, such as growth-promoting substances, or mechanical, for example the stiffness or softness of the environment. Mechanical signals can be detected by load-bearing proteins, which stretch like tiny springs in response to forces. In animals, these proteins span the membrane separating the interior of the cell from the exterior. Externally, the proteins attach to structures around the cell; internally, they connect to the machinery that both generates forces and allows cells to respond to signals from outside. As such, load-bearing proteins form a direct mechanical link between cell and environment. Scientists use tools called molecular tension sensors to measure how much a load-bearing protein stretches in response to changes, and the force that is being applied to it. However, just like any other type of scale, these sensors only work over a certain range, which happens to be limited. This means that, for example, they cannot measure forces in tissues that are too soft (like the brain), or too stiff (such as bones). New sensors that can assess forces in these contexts are therefore needed, but so far research in this area has been slow due to a reliance on ‘trial-and-error’ approaches. Here, LaCroix et al. developed a new method to predict the sensitivity of molecular tension sensors inside cells. This was accomplished by examining several existing sensors, and identifying which components could be altered to change the properties of the sensors. Then, this information was used to create a computer model that could predict how new sensors would behave, and which range of forces they could measure. Finally, the sensors designed following this method were tested in mouse cells grown in the laboratory, and they worked better than their predecessors. The next step was for LaCroix et al. to use a trio of new sensors with different sensitivities to study the load-bearing protein vinculin in mouse cells. The goal was to figure out exactly how cells manage their load-bearing proteins. Indeed, it was widely assumed that a cell acts on a load-bearing protein by applying a force on it. In response, the protein would stretch by a certain amount, which can change depending on its properties – a ‘stiffer’ protein would stretch less. Unexpectedly, the new sensors showed that cells instead manipulate how much vinculin stretches, applying varying forces to achieve the same length of the protein in different environments. Improved molecular tension sensors will give scientists a better insight into how cells respond to their mechanical environment, which could help to direct cell behavior in tissues engineered in the laboratory. This knowledge is also directly relevant to human health, as the mechanical properties of many tissues change during disease, such as tumors stiffening during cancer.
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Affiliation(s)
- Andrew S LaCroix
- Department of Biomedical Engineering, Duke University, Durham, United States
| | - Andrew D Lynch
- Department of Biomedical Engineering, Duke University, Durham, United States
| | - Matthew E Berginski
- Department of Biomedical Engineering, Duke University, Durham, United States
| | - Brenton D Hoffman
- Department of Biomedical Engineering, Duke University, Durham, United States
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Abstract
Productive chromosome movements require that a large multiprotein complex called the kinetochore assemble on sister centromeres. The kinetochore fulfills two critical functions as (1) the physical linkage between chromosomes and spindle microtubules and (2) a mechanomolecular sensor that relays a spindle assembly checkpoint signal delaying anaphase onset until chromosomes are attached to spindle microtubules and bioriented. Given its central roles in such a vital process, the kinetochore is one of the most important force-transducing structures in cells; yet it has been technically challenging to measure kinetochore forces. Barriers to measuring cellular forces have begun to be broken by the development of fluorescence-based tension sensors. In this chapter, two methods will be described for measuring kinetochore forces in living cells and strategies for applying these sensors to other force-transducing processes and molecules will be discussed.
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Ringer P, Colo G, Fässler R, Grashoff C. Sensing the mechano-chemical properties of the extracellular matrix. Matrix Biol 2017; 64:6-16. [DOI: 10.1016/j.matbio.2017.03.004] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Revised: 03/29/2017] [Accepted: 03/30/2017] [Indexed: 12/13/2022]
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46
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Fine N, Dimitriou ID, Rottapel R. Go with the flow: GEF-H1 mediated shear stress mechanotransduction in neutrophils. Small GTPases 2017; 11:23-31. [PMID: 29188751 DOI: 10.1080/21541248.2017.1332505] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Neutrophils in circulation experience significant shear forces due to blood flow when they tether to the vascular endothelium. Biochemical and biophysical responses of neutrophils to the physical force of flowing blood modulate their behavior and promote tissue recruitment under pro-inflammatory conditions. Neutrophil mechanotransduction responses occur through mechanisms that are not yet fully understood. In our recent work, we showed that GEF-H1, a RhoA specific guanine nucleotide exchange factor (GEF), is required to maintain neutrophil motility and migration in response to shear stress. GEF-H1 re-localizes to flottilin-rich uropods in neutrophils in response to fluid shear stress and promotes spreading and crawling on activated endothelial cells. GEF-H1 drives cellular contractility through myosin light chain (MLC) phosphorylation downstream of the Rho-ROCK signaling axis. We propose that GEF-H1-dependent cell spreading and crawling in shear stress-dependent neutrophil recruitment from the vasculature are due to the specific localization of Rho-induced contractility in the uropod.
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Affiliation(s)
- Noah Fine
- Matrix Dynamics Group, University of Toronto, Toronto, Ontario, Canada
| | - Ioannis D Dimitriou
- Princess Margaret Cancer Center, Toronto Medical Discovery Tower, Toronto, Ontario, Canada
| | - Robert Rottapel
- Princess Margaret Cancer Center, Toronto Medical Discovery Tower, Toronto, Ontario, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada.,Department of Immunology, University of Toronto, Toronto, Ontario, Canada.,Department of Medicine, University of Toronto, Toronto, Ontario, Canada
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47
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Multiplexing molecular tension sensors reveals piconewton force gradient across talin-1. Nat Methods 2017; 14:1090-1096. [DOI: 10.1038/nmeth.4431] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 08/18/2017] [Indexed: 01/09/2023]
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48
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Mooney P, Sulerud T, Pelletier J, Dilsaver M, Tomschik M, Geisler C, Gatlin JC. Tau-based fluorescent protein fusions to visualize microtubules. Cytoskeleton (Hoboken) 2017; 74:221-232. [PMID: 28407416 PMCID: PMC5592782 DOI: 10.1002/cm.21368] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 04/03/2017] [Accepted: 04/10/2017] [Indexed: 01/10/2023]
Abstract
The ability to visualize cytoskeletal proteins and their dynamics in living cells has been critically important in advancing our understanding of numerous cellular processes, including actin- and microtubule (MT)-dependent phenomena such as cell motility, cell division, and mitosis. Here, we describe a novel set of fluorescent protein (FP) fusions designed specifically to visualize MTs in living systems using fluorescence microscopy. Each fusion contains a FP module linked in frame to a modified phospho-deficient version of the MT-binding domain of Tau (mTMBD). We found that expressed and purified constructs containing a single mTMBD decorated Xenopus egg extract spindles more homogenously than similar constructs containing the MT-binding domain of Ensconsin, suggesting that the binding affinity of mTMBD is minimally affected by localized signaling gradients generated during mitosis. Furthermore, MT dynamics were not grossly perturbed by the presence of Tau-based FP fusions. Interestingly, the addition of a second mTMBD to the opposite terminus of our construct caused dramatic changes to the spatial localization of probes within spindles. These results support the use of Tau-based FP fusions as minimally perturbing tools to accurately visualize MTs in living systems.
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Affiliation(s)
- Paul Mooney
- Department of Molecular Biology, University of Wyoming, Laramie, WY,
82071, USA
- Molecular & Cellular Life Sciences Program, University of
Wyoming, Laramie, WY, 82071, USA
- Cell Organization and Division Group, Marine Biological
Laboratories, Woods Hole, MA, 02543, USA
| | - Taylor Sulerud
- Department of Molecular Biology, University of Wyoming, Laramie, WY,
82071, USA
- Molecular & Cellular Life Sciences Program, University of
Wyoming, Laramie, WY, 82071, USA
- Cell Organization and Division Group, Marine Biological
Laboratories, Woods Hole, MA, 02543, USA
| | - James Pelletier
- Cell Organization and Division Group, Marine Biological
Laboratories, Woods Hole, MA, 02543, USA
- Department of Systems Biology, Harvard Medical School, Boston, MA,
02115, USA
| | - Matthew Dilsaver
- Department of Molecular Biology, University of Wyoming, Laramie, WY,
82071, USA
| | - Miroslav Tomschik
- Department of Molecular Biology, University of Wyoming, Laramie, WY,
82071, USA
| | | | - Jesse C. Gatlin
- Department of Molecular Biology, University of Wyoming, Laramie, WY,
82071, USA
- Molecular & Cellular Life Sciences Program, University of
Wyoming, Laramie, WY, 82071, USA
- Cell Organization and Division Group, Marine Biological
Laboratories, Woods Hole, MA, 02543, USA
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49
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Mechanical forces during muscle development. Mech Dev 2017; 144:92-101. [DOI: 10.1016/j.mod.2016.11.003] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2016] [Revised: 11/20/2016] [Accepted: 11/21/2016] [Indexed: 01/09/2023]
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50
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Coltharp C, Xiao J. Beyond force generation: Why is a dynamic ring of FtsZ polymers essential for bacterial cytokinesis? Bioessays 2016; 39:1-11. [PMID: 28004447 DOI: 10.1002/bies.201600179] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
We propose that the essential function of the most highly conserved protein in bacterial cytokinesis, FtsZ, is not to generate a mechanical force to drive cell division. Rather, we suggest that FtsZ acts as a signal-processing hub to coordinate cell wall synthesis at the division septum with a diverse array of cellular processes, ensuring that the cell divides smoothly at the correct time and place, and with the correct septum morphology. Here, we explore how the polymerization properties of FtsZ, which have been widely attributed to force generation, can also be advantageous in this signal processing role. We suggest mechanisms by which FtsZ senses and integrates both mechanical and biochemical signals, and conclude by proposing experiments to investigate how FtsZ contributes to the remarkable spatial and temporal precision of bacterial cytokinesis.
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Affiliation(s)
- Carla Coltharp
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Jie Xiao
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, MD, USA
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