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Hussain S, Sedlacek M, Cui R, Zhang-Hooks W, Bergles D, Bum-Shin J, Kindt KS, Kachar B. Spontaneous calcium transients in hair cell stereocilia. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.12.607658. [PMID: 39185174 PMCID: PMC11343103 DOI: 10.1101/2024.08.12.607658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 08/27/2024]
Abstract
The hair bundle of auditory and vestibular hair cells converts mechanical stimuli into electrical signals through mechanoelectrical transduction (MET). The MET apparatus is built around a tip link that connects neighboring stereocilia that are aligned in the direction of mechanosensitivity of the hair bundle. Upon stimulation, the MET channel complex responds to changes in tip-link tension and allows a cation influx into the cell. Ca2+ influx in stereocilia has been used as a signature of MET activity. Using genetically encoded Ca2+ sensors (GCaMP3, GCaMP6s) and high-performance fluorescence confocal microscopy, we detect spontaneous Ca2+ transients in individual stereocilia in developing and fully formed hair bundles. We demonstrate that this activity is abolished by MET channel blockers and thus likely originates from putative MET channels. We observe Ca2+ transients in the stereocilia of mice in tissue explants as well as in vivo in zebrafish hair cells, indicating this activity is functionally conserved. Within stereocilia, the origin of Ca2+ transients is not limited to the canonical MET site at the stereocilia tip but is also present along the stereocilia length. Remarkably, we also observe these Ca2+ transients in the microvilli-like structures on the hair cell surface in the early stages of bundle development, prior to the onset of MET. Ca2+ transients are also present in the tallest rows of stereocilia in auditory hair cells, structures not traditionally thought to contain MET channels. We hypothesize that this newly described activity may reflect stochastic and spontaneous MET channel opening. Localization of these transients to other regions of the stereocilia indicates the presence of a pool of channels or channel precursors. Our work provides insights into MET channel assembly, maturation, function, and turnover.
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Affiliation(s)
- Saman Hussain
- Laboratory of Cell Structure and Dynamics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA
| | - Miloslav Sedlacek
- Laboratory of Cell Structure and Dynamics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA
| | - Runjia Cui
- Laboratory of Cell Structure and Dynamics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA
| | - Wendy Zhang-Hooks
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Dwight Bergles
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Otolaryngology-Head & Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Kavli Neuroscience Discovery Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Jung Bum-Shin
- Department of Neuroscience, University of Virginia, Charlottesville, VA 22908
| | - Katie S. Kindt
- Laboratory of Cellular Biology, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA
| | - Bechara Kachar
- Laboratory of Cell Structure and Dynamics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA
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2
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Rajput SS, Singh SB, Subramanyam D, Patil S. Soft glassy rheology of single cells with pathogenic protein aggregates. SOFT MATTER 2024; 20:6266-6274. [PMID: 39054893 DOI: 10.1039/d4sm00595c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/27/2024]
Abstract
A correlation between the mechanical properties of cells and various diseases has been emerging in recent years. Atomic force microscopy (AFM) has been widely used to measure a single cell's apparent Young's modulus by treating it as a fully elastic object. More recently, quantitative characterization of the complete viscoelasticity of single cells has become possible. We performed AFM-based nano-indentation experiments on hemocytes isolated from third instar larvae to determine their viscoelasticity and found that live hemocytes, like many other cells, follow a scale-free power-law rheology (PLR) akin to soft glasses. Further, we examined the changes in the rheological response of hemocytes in the presence of pathogenic protein aggregates known to cause neurodegenerative diseases such as Huntington's disorder and amyotrophic lateral sclerosis. Our results show that cells lose their fluidity and appear more solid-like in the presence of certain aggregates, in a manner correlated to actin reorganization. More solid-like cells also display reduced intracellular transport through clathrin-mediated endocytosis (CME). However, the cell's rheology remains largely unaffected and is similar to that of wild-type (WT) hemocytes, if aggregates do not perturb the actin organization and CME. Moreover, the fluid-like nature was significantly recovered when actin organization was rescued by overexpressing specific actin interacting proteins or chaperones. Our study, for the first time, underscores a direct correlation between parameters governing glassy dynamics, actin organization and CME.
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Affiliation(s)
- Shatruhan Singh Rajput
- Department of Physics, Indian Institute of Science Education and Research, Pune 411008, India
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, UK
| | - Surya Bansi Singh
- National Centre for Cell Science, SP Pune University Campus, Pune 411007, India.
- SP Pune University, Pune 411007, India
| | - Deepa Subramanyam
- National Centre for Cell Science, SP Pune University Campus, Pune 411007, India.
| | - Shivprasad Patil
- Department of Physics, Indian Institute of Science Education and Research, Pune 411008, India.
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3
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Dieper A, Scheidegger S, Füchslin RM, Veltsista PD, Stein U, Weyland M, Gerster D, Beck M, Bengtsson O, Zips D, Ghadjar P. Literature review: potential non-thermal molecular effects of external radiofrequency electromagnetic fields on cancer. Int J Hyperthermia 2024; 41:2379992. [PMID: 39019469 DOI: 10.1080/02656736.2024.2379992] [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: 02/16/2024] [Accepted: 07/10/2024] [Indexed: 07/19/2024] Open
Abstract
INTRODUCTION There is an ongoing scientific discussion, that anti-cancer effects induced by radiofrequency (RF)-hyperthermia might not be solely attributable to subsequent temperature elevations at the tumor site but also to non-temperature-induced effects. The exact molecular mechanisms behind said potential non-thermal RF effects remain largely elusive, however, limiting their therapeutical targetability. OBJECTIVE Therefore, we aim to provide an overview of the current literature on potential non-temperature-induced molecular effects within cancer cells in response to RF-electromagnetic fields (RF-EMF). MATERIAL AND METHODS This literature review was conducted following the PRISMA guidelines. For this purpose, a MeSH-term-defined literature search on MEDLINE (PubMed) and Scopus (Elsevier) was conducted on March 23rd, 2024. Essential criteria herein included the continuous wave RF-EMF nature (3 kHz - 300 GHz) of the source, the securing of temperature-controlled circumstances within the trials, and the preclinical nature of the trials. RESULTS Analysis of the data processed in this review suggests that RF-EMF radiation of various frequencies seems to be able to induce significant non-temperature-induced anti-cancer effects. These effects span from mitotic arrest and growth inhibition to cancer cell death in the form of autophagy and apoptosis and appear to be mostly exclusive to cancer cells. Several cellular mechanisms were identified through which RF-EMF radiation potentially imposes its anti-cancer effects. Among those, by reviewing the included publications, we identified RF-EMF-induced ion channel activation, altered gene expression, altered membrane potentials, membrane oscillations, and blebbing, as well as changes in cytoskeletal structure and cell morphology. CONCLUSION The existent literature points toward a yet untapped therapeutic potential of RF-EMF treatment, which might aid in damaging cancer cells through bio-electrical and electro-mechanical molecular mechanisms while minimizing adverse effects on healthy tissue cells. Further research is imperative to definitively confirm non-thermal EMF effects as well as to determine optimal cancer-type-specific RF-EMF frequencies, field intensities, and exposure intervals.
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Affiliation(s)
- Anna Dieper
- Department of Radiation Oncology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Stephan Scheidegger
- Institute for Applied Mathematics and Physics, Zurich University of Applied Sciences, Winterthur, Switzerland
| | - Rudolf M Füchslin
- Institute for Applied Mathematics and Physics, Zurich University of Applied Sciences, Winterthur, Switzerland
- Experimental and Clinical Research Center, Charité-Universitätsmedizin Berlin and Max-Delbrück-Centrum (MDC), Berlin, Germany
| | - Paraskevi D Veltsista
- Department of Radiation Oncology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Ulrike Stein
- Experimental and Clinical Research Center, Charité-Universitätsmedizin Berlin and Max-Delbrück-Centrum (MDC), Berlin, Germany
| | - Mathias Weyland
- Institute for Applied Mathematics and Physics, Zurich University of Applied Sciences, Winterthur, Switzerland
| | - Dominik Gerster
- Department of Radiation Oncology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Marcus Beck
- Department of Radiation Oncology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Olof Bengtsson
- Ferdinand-Braun-Institut (FBH), Leibnitz-Institut für Höchstfrequenztechnik, Berlin, Germany
| | - Daniel Zips
- Department of Radiation Oncology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Pirus Ghadjar
- Department of Radiation Oncology, Charité - Universitätsmedizin Berlin, Berlin, Germany
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4
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Wang S, Ma S, Li H, Dao M, Li X, Karniadakis GE. Two-component macrophage model for active phagocytosis with pseudopod formation. Biophys J 2024; 123:1069-1084. [PMID: 38532625 PMCID: PMC11079866 DOI: 10.1016/j.bpj.2024.03.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 11/20/2023] [Accepted: 03/21/2024] [Indexed: 03/28/2024] Open
Abstract
Macrophage phagocytosis is critical for the immune response, homeostasis regulation, and tissue repair. This intricate process involves complex changes in cell morphology, cytoskeletal reorganization, and various receptor-ligand interactions controlled by mechanical constraints. However, there is a lack of comprehensive theoretical and computational models that investigate the mechanical process of phagocytosis in the context of cytoskeletal rearrangement. To address this issue, we propose a novel coarse-grained mesoscopic model that integrates a fluid-like cell membrane and a cytoskeletal network to study the dynamic phagocytosis process. The growth of actin filaments results in the formation of long and thin pseudopods, and the initial cytoskeleton can be disassembled upon target entry and reconstructed after phagocytosis. Through dynamic changes in the cytoskeleton, our macrophage model achieves active phagocytosis by forming a phagocytic cup utilizing pseudopods in two distinct ways. We have developed a new algorithm for modifying membrane area to prevent membrane rupture and ensure sufficient surface area during phagocytosis. In addition, the bending modulus, shear stiffness, and cortical tension of the macrophage model are investigated through computation of the axial force for the tubular structure and micropipette aspiration. With this model, we simulate active phagocytosis at the cytoskeletal level and investigate the mechanical process during the dynamic interplay between macrophage and target particles.
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Affiliation(s)
- Shuo Wang
- Department of Engineering Mechanics and Center for X-Mechanics, Zhejiang University, Hangzhou, Zhejiang, China
| | - Shuhao Ma
- Department of Engineering Mechanics and Center for X-Mechanics, Zhejiang University, Hangzhou, Zhejiang, China
| | - He Li
- School of Chemical, Materials and Biomedical Engineering, University of Georgia, Athens, Georgia
| | - Ming Dao
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Xuejin Li
- Department of Engineering Mechanics and Center for X-Mechanics, Zhejiang University, Hangzhou, Zhejiang, China.
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5
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Erazo-Oliveras A, Muñoz-Vega M, Salinas ML, Wang X, Chapkin RS. Dysregulation of cellular membrane homeostasis as a crucial modulator of cancer risk. FEBS J 2024; 291:1299-1352. [PMID: 36282100 PMCID: PMC10126207 DOI: 10.1111/febs.16665] [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: 06/18/2022] [Revised: 09/09/2022] [Accepted: 10/24/2022] [Indexed: 11/07/2022]
Abstract
Cellular membranes serve as an epicentre combining extracellular and cytosolic components with membranous effectors, which together support numerous fundamental cellular signalling pathways that mediate biological responses. To execute their functions, membrane proteins, lipids and carbohydrates arrange, in a highly coordinated manner, into well-defined assemblies displaying diverse biological and biophysical characteristics that modulate several signalling events. The loss of membrane homeostasis can trigger oncogenic signalling. More recently, it has been documented that select membrane active dietaries (MADs) can reshape biological membranes and subsequently decrease cancer risk. In this review, we emphasize the significance of membrane domain structure, organization and their signalling functionalities as well as how loss of membrane homeostasis can steer aberrant signalling. Moreover, we describe in detail the complexities associated with the examination of these membrane domains and their association with cancer. Finally, we summarize the current literature on MADs and their effects on cellular membranes, including various mechanisms of dietary chemoprevention/interception and the functional links between nutritional bioactives, membrane homeostasis and cancer biology.
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Affiliation(s)
- Alfredo Erazo-Oliveras
- Program in Integrative Nutrition and Complex Diseases; Texas A&M University; College Station, Texas, 77843; USA
- Department of Nutrition; Texas A&M University; College Station, Texas, 77843; USA
| | - Mónica Muñoz-Vega
- Program in Integrative Nutrition and Complex Diseases; Texas A&M University; College Station, Texas, 77843; USA
- Department of Nutrition; Texas A&M University; College Station, Texas, 77843; USA
| | - Michael L. Salinas
- Program in Integrative Nutrition and Complex Diseases; Texas A&M University; College Station, Texas, 77843; USA
- Department of Nutrition; Texas A&M University; College Station, Texas, 77843; USA
| | - Xiaoli Wang
- Program in Integrative Nutrition and Complex Diseases; Texas A&M University; College Station, Texas, 77843; USA
- Department of Nutrition; Texas A&M University; College Station, Texas, 77843; USA
| | - Robert S. Chapkin
- Program in Integrative Nutrition and Complex Diseases; Texas A&M University; College Station, Texas, 77843; USA
- Department of Nutrition; Texas A&M University; College Station, Texas, 77843; USA
- Center for Environmental Health Research; Texas A&M University; College Station, Texas, 77843; USA
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6
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Stilgoe A, Favre-Bulle IA, Watson ML, Gomez-Godinez V, Berns MW, Preece D, Rubinsztein-Dunlop H. Shining Light in Mechanobiology: Optical Tweezers, Scissors, and Beyond. ACS PHOTONICS 2024; 11:917-940. [PMID: 38523746 PMCID: PMC10958612 DOI: 10.1021/acsphotonics.4c00064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 02/22/2024] [Accepted: 02/23/2024] [Indexed: 03/26/2024]
Abstract
Mechanobiology helps us to decipher cell and tissue functions by looking at changes in their mechanical properties that contribute to development, cell differentiation, physiology, and disease. Mechanobiology sits at the interface of biology, physics and engineering. One of the key technologies that enables characterization of properties of cells and tissue is microscopy. Combining microscopy with other quantitative measurement techniques such as optical tweezers and scissors, gives a very powerful tool for unraveling the intricacies of mechanobiology enabling measurement of forces, torques and displacements at play. We review the field of some light based studies of mechanobiology and optical detection of signal transduction ranging from optical micromanipulation-optical tweezers and scissors, advanced fluorescence techniques and optogenentics. In the current perspective paper, we concentrate our efforts on elucidating interesting measurements of forces, torques, positions, viscoelastic properties, and optogenetics inside and outside a cell attained when using structured light in combination with optical tweezers and scissors. We give perspective on the field concentrating on the use of structured light in imaging in combination with tweezers and scissors pointing out how novel developments in quantum imaging in combination with tweezers and scissors can bring to this fast growing field.
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Affiliation(s)
- Alexander
B. Stilgoe
- School of
Mathematics and Physics, The University
of Queensland, Brisbane, 4074, Australia
- ARC
CoE for Engineered Quantum Systems, The
University of Queensland, Brisbane, 4074, Australia
- ARC
CoE in Quantum Biotechnology, The University
of Queensland, 4074, Brisbane, Australia
| | - Itia A. Favre-Bulle
- School of
Mathematics and Physics, The University
of Queensland, Brisbane, 4074, Australia
- Queensland
Brain Institute, The University of Queensland, Brisbane, 4074, Australia
| | - Mark L. Watson
- School of
Mathematics and Physics, The University
of Queensland, Brisbane, 4074, Australia
- ARC
CoE for Engineered Quantum Systems, The
University of Queensland, Brisbane, 4074, Australia
| | - Veronica Gomez-Godinez
- Institute
of Engineering and Medicine, University
of California San Diego, San Diego, California 92093, United States
| | - Michael W. Berns
- Institute
of Engineering and Medicine, University
of California San Diego, San Diego, California 92093, United States
- Beckman
Laser Institute, University of California
Irvine, Irvine, California 92612, United States
| | - Daryl Preece
- Beckman
Laser Institute, University of California
Irvine, Irvine, California 92612, United States
| | - Halina Rubinsztein-Dunlop
- School of
Mathematics and Physics, The University
of Queensland, Brisbane, 4074, Australia
- ARC
CoE for Engineered Quantum Systems, The
University of Queensland, Brisbane, 4074, Australia
- ARC
CoE in Quantum Biotechnology, The University
of Queensland, 4074, Brisbane, Australia
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7
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Bonilla-Quintana M, Rangamani P. Biophysical Modeling of Actin-Mediated Structural Plasticity Reveals Mechanical Adaptation in Dendritic Spines. eNeuro 2024; 11:ENEURO.0497-23.2024. [PMID: 38383589 DOI: 10.1523/eneuro.0497-23.2024] [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: 11/27/2023] [Accepted: 01/13/2024] [Indexed: 02/23/2024] Open
Abstract
Synaptic plasticity is important for learning and memory formation; it describes the strengthening or weakening of connections between synapses. The postsynaptic part of excitatory synapses resides in dendritic spines, which are small protrusions on the dendrites. One of the key features of synaptic plasticity is its correlation with the size of these spines. A long-lasting synaptic strength increase [long-term potentiation (LTP)] is only possible through the reconfiguration of the actin spine cytoskeleton. Here, we develop an experimentally informed three-dimensional computational model in a moving boundary framework to investigate this reconfiguration. Our model describes the reactions between actin and actin-binding proteins leading to the cytoskeleton remodeling and their effect on the spine membrane shape to examine the spine enlargement upon LTP. Moreover, we find that the incorporation of perisynaptic elements enhances spine enlargement upon LTP, exhibiting the importance of accounting for these elements when studying structural LTP. Our model shows adaptation to repeated stimuli resulting from the interactions between spine proteins and mechanical forces.
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Affiliation(s)
- Mayte Bonilla-Quintana
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, California 92093
| | - Padmini Rangamani
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, California 92093
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8
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Yang F, Chen W, Chen Z. Photoacoustic micro-viscoelastography for mapping mechanocellular properties. JOURNAL OF BIOPHOTONICS 2024; 17:e202300262. [PMID: 37738101 DOI: 10.1002/jbio.202300262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Revised: 08/22/2023] [Accepted: 09/19/2023] [Indexed: 09/24/2023]
Abstract
Cellular biomechanical properties provide essential insights into biological functions regarding health and disease. Current measurements of the biomechanical properties of cells require physical contact with cells or pre-loading on the cells. Here, we have developed photoacoustic micro-viscoelastography (PAMVE), which utilizes the phase characteristics of photoacoustic (PA) response, for mapping mechanocellular properties in a load-free manner. PAMVE realizes the local viscoelasticity measurement on the macrophages and red blood cells with micrometer scale. Furthermore, PAMVE can successfully identify the adipose cell and skeletal muscle cell due to the difference in their composition-related biomechanical properties. PAMVE represents an irreplaceable option for interrogating characteristic mechanocellular properties, opening the possibility of studying cellular mechanobiology and pathophysiology.
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Affiliation(s)
- Fen Yang
- Department of Biomedical Engineering, Guangdong Provincial Key Laboratory of Advanced Biomaterials, Southern University of Science and Technology, Shenzhen, Guangdong, China
- MOE Key Laboratory of Laser Life Science and Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou, China
| | - Wei Chen
- Department of Biomedical Engineering, Guangdong Provincial Key Laboratory of Advanced Biomaterials, Southern University of Science and Technology, Shenzhen, Guangdong, China
| | - Zhongjiang Chen
- School of Medical Technology and Engineering, Fujian Medical University, Fuzhou, China
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9
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De Belly H, Yan S, Borja da Rocha H, Ichbiah S, Town JP, Zager PJ, Estrada DC, Meyer K, Turlier H, Bustamante C, Weiner OD. Cell protrusions and contractions generate long-range membrane tension propagation. Cell 2023; 186:3049-3061.e15. [PMID: 37311454 PMCID: PMC10330871 DOI: 10.1016/j.cell.2023.05.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 03/10/2023] [Accepted: 05/11/2023] [Indexed: 06/15/2023]
Abstract
Membrane tension is thought to be a long-range integrator of cell physiology. Membrane tension has been proposed to enable cell polarity during migration through front-back coordination and long-range protrusion competition. These roles necessitate effective tension transmission across the cell. However, conflicting observations have left the field divided as to whether cell membranes support or resist tension propagation. This discrepancy likely originates from the use of exogenous forces that may not accurately mimic endogenous forces. We overcome this complication by leveraging optogenetics to directly control localized actin-based protrusions or actomyosin contractions while simultaneously monitoring the propagation of membrane tension using dual-trap optical tweezers. Surprisingly, actin-driven protrusions and actomyosin contractions both elicit rapid global membrane tension propagation, whereas forces applied to cell membranes alone do not. We present a simple unifying mechanical model in which mechanical forces that engage the actin cortex drive rapid, robust membrane tension propagation through long-range membrane flows.
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Affiliation(s)
- Henry De Belly
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, USA; Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA, USA
| | - Shannon Yan
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Hudson Borja da Rocha
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS, Inserm, Université PSL, Paris, France
| | - Sacha Ichbiah
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS, Inserm, Université PSL, Paris, France
| | - Jason P Town
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, USA; Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA, USA
| | - Patrick J Zager
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, USA; Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA, USA
| | - Dorothy C Estrada
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, USA; Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA, USA
| | - Kirstin Meyer
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, USA; Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA, USA
| | - Hervé Turlier
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS, Inserm, Université PSL, Paris, France.
| | - Carlos Bustamante
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, CA 94720, USA; Jason L. Choy Laboratory of Single-Molecule Biophysics, University of California, Berkeley, Berkeley, CA, USA; Department of Physics, University of California, Berkeley, Berkeley, CA, USA; Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA, USA; Kavli Energy Nanoscience Institute, University of California, Berkeley, Berkeley, CA, USA.
| | - Orion D Weiner
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, USA; Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA, USA.
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10
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Ivan DC, Berve KC, Walthert S, Monaco G, Borst K, Bouillet E, Ferreira F, Lee H, Steudler J, Buch T, Prinz M, Engelhardt B, Locatelli G. Insulin-like growth factor-1 receptor controls the function of CNS-resident macrophages and their contribution to neuroinflammation. Acta Neuropathol Commun 2023; 11:35. [PMID: 36890580 PMCID: PMC9993619 DOI: 10.1186/s40478-023-01535-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 02/20/2023] [Indexed: 03/10/2023] Open
Abstract
Signaling by insulin-like growth factor-1 (IGF-1) is essential for the development of the central nervous system (CNS) and regulates neuronal survival and myelination in the adult CNS. In neuroinflammatory conditions including multiple sclerosis (MS) and its animal model experimental autoimmune encephalomyelitis (EAE), IGF-1 can regulate cellular survival and activation in a context-dependent and cell-specific manner. Notwithstanding its importance, the functional outcome of IGF-1 signaling in microglia/macrophages, which maintain CNS homeostasis and regulate neuroinflammation, remains undefined. As a result, contradictory reports on the disease-ameliorating efficacy of IGF-1 are difficult to interpret, together precluding its potential use as a therapeutic agent. To fill this gap, we here investigated the role of IGF-1 signaling in CNS-resident microglia and border associated macrophages (BAMs) by conditional genetic deletion of the receptor Igf1r in these cell types. Using a series of techniques including histology, bulk RNA sequencing, flow cytometry and intravital imaging, we show that absence of IGF-1R significantly impacted the morphology of both BAMs and microglia. RNA analysis revealed minor changes in microglia. In BAMs however, we detected an upregulation of functional pathways associated with cellular activation and a decreased expression of adhesion molecules. Notably, genetic deletion of Igf1r from CNS-resident macrophages led to a significant weight gain in mice, suggesting that absence of IGF-1R from CNS-resident myeloid cells indirectly impacts the somatotropic axis. Lastly, we observed a more severe EAE disease course upon Igf1r genetic ablation, thus highlighting an important immunomodulatory role of this signaling pathway in BAMs/microglia. Taken together, our work shows that IGF-1R signaling in CNS-resident macrophages regulates the morphology and transcriptome of these cells while significantly decreasing the severity of autoimmune CNS inflammation.
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Affiliation(s)
- Daniela C Ivan
- Theodor Kocher Institute, University of Bern, Freiestrasse 1, CH-3012, Bern, Switzerland
| | - Kristina Carolin Berve
- Theodor Kocher Institute, University of Bern, Freiestrasse 1, CH-3012, Bern, Switzerland
| | - Sabrina Walthert
- Theodor Kocher Institute, University of Bern, Freiestrasse 1, CH-3012, Bern, Switzerland
| | - Gianni Monaco
- Institute of Neuropathology, University of Freiburg, Freiburg, Germany
| | - Katharina Borst
- Institute of Neuropathology, University of Freiburg, Freiburg, Germany
| | - Elisa Bouillet
- Theodor Kocher Institute, University of Bern, Freiestrasse 1, CH-3012, Bern, Switzerland
| | - Filipa Ferreira
- Institute of Laboratory Animal Science, University of Zurich, Zurich, Switzerland
| | - Henry Lee
- Theodor Kocher Institute, University of Bern, Freiestrasse 1, CH-3012, Bern, Switzerland
| | - Jasmin Steudler
- Theodor Kocher Institute, University of Bern, Freiestrasse 1, CH-3012, Bern, Switzerland
| | - Thorsten Buch
- Institute of Laboratory Animal Science, University of Zurich, Zurich, Switzerland
| | - Marco Prinz
- Institute of Neuropathology, University of Freiburg, Freiburg, Germany.,Center for Basics in NeuroModulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany
| | - Britta Engelhardt
- Theodor Kocher Institute, University of Bern, Freiestrasse 1, CH-3012, Bern, Switzerland
| | - Giuseppe Locatelli
- Theodor Kocher Institute, University of Bern, Freiestrasse 1, CH-3012, Bern, Switzerland.
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11
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Daniel M, Eleršič Filipič K, Filová E, Judl T, Fojt J. Modelling the role of membrane mechanics in cell adhesion on titanium oxide nanotubes. Comput Methods Biomech Biomed Engin 2023; 26:281-290. [PMID: 35380071 DOI: 10.1080/10255842.2022.2058875] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Titanium surface treated with titanium oxide nanotubes was used in many studies to quantify the effect of surface topography on cell fate. However, the predicted optimal diameter of nanotubes considerably differs among studies. We propose a model that explains cell adhesion to a nanostructured surface by considering the deformation energy of cell protrusions into titanium nanotubes and the adhesion to the surface. The optimal surface topology is defined as a geometry that gives the membrane a minimum energy shape. A dimensionless parameter, the cell interaction index, was proposed to describe the interplay between the cell membrane bending, the intrinsic curvature, and the strength of cell adhesion. Model simulation shows that an optimal nanotube diameter ranging from 20 nm to 100 nm (cell interaction index between 0.2 and 1, respectively) is feasible within a certain range of parameters describing cell membrane adhesion and bending. The results indicate a possibility to tune the topology of a nanostructural surface in order to enhance the proliferation and differentiation of cells mechanically compatible with the given surface geometry while suppressing the growth of other mechanically incompatible cells.
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Affiliation(s)
- Matej Daniel
- Faculty of Mechanical Engineering, Czech Technical University in Prague, Prague, Czechia
| | | | - Eva Filová
- Institute of Experimental Medicine of the Czech Academy of Sciences, Prague, Czechia
| | | | - Jaroslav Fojt
- Faculty of Chemical Technology, University of Chemistry and Technology Prague, Prague, Czechia
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12
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Shu W, Kaplan CN. A multiscale whole-cell theory for mechanosensitive migration on viscoelastic substrates. Biophys J 2023; 122:114-129. [PMID: 36493781 PMCID: PMC9822805 DOI: 10.1016/j.bpj.2022.11.022] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 09/25/2022] [Accepted: 11/14/2022] [Indexed: 12/13/2022] Open
Abstract
Increasing experimental evidence validates that both the elastic stiffness and viscosity of the extracellular matrix regulate mesenchymal cell behavior, such as the rational switch between durotaxis (cell migration to stiffer regions), anti-durotaxis (migration to softer regions), and adurotaxis (stiffness-insensitive migration). To reveal the mechanisms underlying the crossover between these motility regimes, we have developed a multiscale chemomechanical whole-cell theory for mesenchymal migration. Our framework couples the subcellular focal adhesion dynamics at the cell-substrate interface with the cellular cytoskeletal mechanics and the chemical signaling pathways involving Rho GTPase proteins. Upon polarization by the Rho GTPase gradients, our simulated cell migrates by concerted peripheral protrusions and contractions, a hallmark of the mesenchymal mode. The resulting cell dynamics quantitatively reproduces the experimental migration speed as a function of the uniform substrate stiffness and explains the influence of viscosity on the migration efficiency. In the presence of stiffness gradients and absence of chemical polarization, our simulated cell can exhibit durotaxis, anti-durotaxis, and adurotaxis respectively with increasing substrate stiffness or viscosity. The cell moves toward an optimally stiff region from softer regions during durotaxis and from stiffer regions during anti-durotaxis. We show that cell polarization through steep Rho GTPase gradients can reverse the migration direction dictated by the mechanical cues. Overall, our theory demonstrates that opposing durotactic behaviors emerge via the interplay between intracellular signaling and cell-medium mechanical interactions in agreement with experiments, thereby elucidating complex mechanosensing at the single-cell level.
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Affiliation(s)
- Wenya Shu
- Department of Physics, Virginia Polytechnic Institute and State University, Blacksburg, Virginia; Center for Soft Matter and Biological Physics, Virginia Polytechnic Institute and State University, Blacksburg, Virginia
| | - C Nadir Kaplan
- Department of Physics, Virginia Polytechnic Institute and State University, Blacksburg, Virginia; Center for Soft Matter and Biological Physics, Virginia Polytechnic Institute and State University, Blacksburg, Virginia.
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13
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Stotsky JA, Othmer HG. The effects of internal forces and membrane heterogeneity on three-dimensional cell shapes. J Math Biol 2022; 86:1. [PMID: 36427179 DOI: 10.1007/s00285-022-01836-x] [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: 03/02/2022] [Revised: 11/07/2022] [Accepted: 11/09/2022] [Indexed: 11/27/2022]
Abstract
The shape of cells and the control thereof plays a central role in a variety of cellular processes, including endo- and exocytosis, cell division and cell movement. Intra- and extracellular forces control the shapes, and while the shape changes in some processes such as exocytosis are intracellularly-controlled and localized in the cell, movement requires force transmission to the environment, and the feedback from it can affect the cell shape and mode of movement used. The shape of a cell is determined by its cytoskeleton (CSK), and thus shape changes involved in various processes involve controlled remodeling of the CSK. While much is known about individual components involved in these processes, an integrated understanding of how intra- and extracellular signals are coupled to the control of the mechanical changes involved is not at hand for any of them. As a first step toward understanding the interaction between intracellular forces imposed on the membrane and cell shape, we investigate the role of distributed surrogates for cortical forces in producing the observed three-dimensional shapes. We show how different balances of applied forces lead to such shapes, that there are different routes to the same end state, and that state transitions between axisymmetric shapes need not all be axisymmetric. Examples of the force distributions that lead to protrusions are given, and the shape changes induced by adhesion of a cell to a surface are studied. The results provide a reference framework for developing detailed models of intracellular force distributions observed experimentally, and provide a basis for studying how movement of a cell in a tissue or fluid is influenced by its shape.
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Affiliation(s)
- Jay A Stotsky
- School of Mathematics, University of Minnesota, Minneapolis, MN, 100190, USA.
| | - Hans G Othmer
- School of Mathematics, University of Minnesota, Minneapolis, MN, 100190, USA
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14
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An evaluation of aging measures: from biomarkers to clocks. Biogerontology 2022; 24:303-328. [PMID: 36418661 DOI: 10.1007/s10522-022-09997-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 10/21/2022] [Indexed: 11/25/2022]
Abstract
With the increasing number of aged population and growing burden of healthy aging demands, a rational standard for evaluation aging is in urgent need. The advancement of medical testing technology and the prospering of artificial intelligence make it possible to evaluate the biological status of aging from a more comprehensive view. In this review, we introduced common aging biomarkers and concluded several famous aging clocks. Aging biomarkers reflect changes in the organism at a molecular or cellular level over time while aging clocks tend to be more of a generalization of the overall state of the organism. We expect to construct a framework for aging evaluation measurement from both micro and macro perspectives. Especially, population-specific aging clocks and multi-omics aging clocks may better fit the demands to evaluate aging in a comprehensive and multidimensional manner and make a detailed classification to represent different aging rates at tissue/organ levels. This framework will promisingly provide a crucial basis for disease diagnosis and intervention assessment in geroscience.
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15
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Controlling the shape and topology of two-component colloidal membranes. Proc Natl Acad Sci U S A 2022; 119:e2204453119. [PMID: 35914159 PMCID: PMC9371715 DOI: 10.1073/pnas.2204453119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Changes in the geometry and topology of self-assembled membranes underlie diverse processes across cellular biology and engineering. Similar to lipid bilayers, monolayer colloidal membranes have in-plane fluid-like dynamics and out-of-plane bending elasticity. Their open edges and micrometer-length scale provide a tractable system to study the equilibrium energetics and dynamic pathways of membrane assembly and reconfiguration. Here, we find that doping colloidal membranes with short miscible rods transforms disk-shaped membranes into saddle-shaped surfaces with complex edge structures. The saddle-shaped membranes are well approximated by Enneper's minimal surfaces. Theoretical modeling demonstrates that their formation is driven by increasing the positive Gaussian modulus, which in turn, is controlled by the fraction of short rods. Further coalescence of saddle-shaped surfaces leads to diverse topologically distinct structures, including shapes similar to catenoids, trinoids, four-noids, and higher-order structures. At long timescales, we observe the formation of a system-spanning, sponge-like phase. The unique features of colloidal membranes reveal the topological transformations that accompany coalescence pathways in real time. We enhance the functionality of these membranes by making their shape responsive to external stimuli. Our results demonstrate a pathway toward control of thin elastic sheets' shape and topology-a pathway driven by the emergent elasticity induced by compositional heterogeneity.
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16
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Benedetto A, Kelley EG. Absorption of the [bmim][Cl] Ionic Liquid in DMPC Lipid Bilayers across Their Gel, Ripple, and Fluid Phases. J Phys Chem B 2022; 126:3309-3318. [PMID: 35472281 PMCID: PMC9082605 DOI: 10.1021/acs.jpcb.2c00710] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 04/11/2022] [Indexed: 12/19/2022]
Abstract
Lipid bilayers are a key component of cell membranes and play a crucial role in life and in bio-nanotechnology. As a result, controlling their physicochemical properties holds the promise of effective therapeutic strategies. Ionic liquids (ILs)─a vast class of complex organic electrolytes─have shown a high degree of affinity with lipid bilayers and can be exploited in this context. However, the chemical physics of IL absorption and partitioning into lipid bilayers is yet to be fully understood. This work focuses on the absorption of the model IL [bmim][Cl] into 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) lipid bilayers across their gel, ripple, and fluid phases. Here, by small-angle neutron scattering, we show that (i) the IL cations are absorbed in the lipid bilayer in all its thermodynamic phases and (ii) the amount of IL inserted into the lipid phase increased with increasing temperature, changing from three to four IL cations per 10 lipids with increasing temperature from 10 °C in the gel phase to 40 °C in the liquid phase, respectively. An explicative hypothesis, based on the entropy gain coming from the IL hydration water, is presented to explain the observed temperature trend. The ability to control IL absorption with temperature can be used as a handle to tune the effect of ILs on biomembranes and can be exploited in bio-nanotechnological applications.
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Affiliation(s)
- Antonio Benedetto
- Department
of Science, University of Roma Tre, 00146 Rome, Italy
- School
of Physics, and Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Dublin 4, Ireland
- Laboratory
for Neutron Scattering, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - Elizabeth G. Kelley
- NIST
Center for Neutron Research, National Institute
of Standards and Technology, Gaithersburg, Maryland 20899, United States
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17
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Lu T, Lee CH, Anvari B. Morphological Characteristics, Hemoglobin Content, and Membrane Mechanical Properties of Red Blood Cell Delivery Systems. ACS APPLIED MATERIALS & INTERFACES 2022; 14:18219-18232. [PMID: 35417121 PMCID: PMC9926936 DOI: 10.1021/acsami.2c03472] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Red blood cell (RBC)-based systems are under extensive development as platforms for the delivery of various biomedical agents. While the importance of the membrane biochemical characteristics in relation to circulation kinetics of RBC delivery systems has been recognized, the membrane mechanical properties of such carriers have not been extensively studied. Using optical methods in conjunction with image analysis and mechanical modeling, we have quantified the morphological and membrane mechanical characteristics of RBC-derived microparticles containing the near-infrared cargo indocyanine green (ICG). We find that these particles have a significantly lower surface area, volume, and deformability as compared to normal RBCs. The residual hemoglobin has a spatially distorted distribution in the particles. The membrane bending modulus of the particles is about twofold higher as compared to normal RBCs and exhibits greater resistance to flow. The induced increase in the viscous characteristics of the membrane is dominant over the elastic and entropic effects of ICG. Our results suggest that changes to the membrane mechanical properties are a result of impaired membrane-cytoskeleton attachment in these particles. We provide a mechanistic explanation to suggest that the compromised membrane-cytoskeleton attachment and altered membrane compositional and structural asymmetry induce curvature changes to the membrane, resulting in mechanical remodeling of the membrane. These findings highlight the importance of membrane mechanical properties as an important criterion in the design and engineering of future generations of RBC-based delivery systems to achieve prolonged circulation.
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Affiliation(s)
- Thompson Lu
- Department of Bioengineering, University of California, Riverside, Riverside, California 92521, United States
| | - Chi-Hua Lee
- Department of Biochemistry, University of California, Riverside, Riverside, California 92521, United States
| | - Bahman Anvari
- Department of Bioengineering, University of California, Riverside, Riverside, California 92521, United States
- Department of Biochemistry, University of California, Riverside, Riverside, California 92521, United States
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18
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Filopodia rotate and coil by actively generating twist in their actin shaft. Nat Commun 2022; 13:1636. [PMID: 35347113 PMCID: PMC8960877 DOI: 10.1038/s41467-022-28961-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 02/10/2022] [Indexed: 12/19/2022] Open
Abstract
Filopodia are actin-rich structures, present on the surface of eukaryotic cells. These structures play a pivotal role by allowing cells to explore their environment, generate mechanical forces or perform chemical signaling. Their complex dynamics includes buckling, pulling, length and shape changes. We show that filopodia additionally explore their 3D extracellular space by combining growth and shrinking with axial twisting and buckling. Importantly, the actin core inside filopodia performs a twisting or spinning motion which is observed for a range of cell types spanning from earliest development to highly differentiated tissue cells. Non-equilibrium physical modeling of actin and myosin confirm that twist is an emergent phenomenon of active filaments confined in a narrow channel which is supported by measured traction forces and helical buckles that can be ascribed to accumulation of sufficient twist. These results lead us to conclude that activity induced twisting of the actin shaft is a general mechanism underlying fundamental functions of filopodia. The authors show how tubular surface structures in all cell types, have the ability to twist and perform rotary sweeping motion to explore the extracellular environment. This has implications for migration, sensing and cell communication.
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19
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Zizzi EA, Cavaglià M, Tuszynski JA, Deriu MA. Alteration of lipid bilayer mechanics by volatile anesthetics: Insights from μs-long molecular dynamics simulations. iScience 2022; 25:103946. [PMID: 35265816 PMCID: PMC8898909 DOI: 10.1016/j.isci.2022.103946] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 01/25/2022] [Accepted: 02/15/2022] [Indexed: 11/24/2022] Open
Abstract
Very few drugs in clinical practice feature the chemical diversity, narrow therapeutic window, unique route of administration, and reversible cognitive effects of volatile anesthetics. The correlation between their hydrophobicity and their potency and the increasing amount of evidence suggesting that anesthetics exert their action on transmembrane proteins, justifies the investigation of their effects on phospholipid bilayers at the molecular level, given the strong functional and structural link between transmembrane proteins and the surrounding lipid matrix. Molecular dynamics simulations of a model lipid bilayer in the presence of ethylene, desflurane, methoxyflurane, and the nonimmobilizer 1,2-dichlorohexafluorocyclobutane (also called F6 or 2N) at different concentrations highlight the structural consequences of VA partitioning in the lipid phase, with a decrease of lipid order and bilayer thickness, an increase in overall lipid lateral mobility and area-per-lipid, and a marked reduction in the mechanical stiffness of the membrane, that strongly correlates with the compounds' hydrophobicity.
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Affiliation(s)
- Eric A. Zizzi
- PolitoMed Lab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, 10129 Turin, Italy
| | - Marco Cavaglià
- PolitoMed Lab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, 10129 Turin, Italy
| | - Jack A. Tuszynski
- PolitoMed Lab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, 10129 Turin, Italy
- Department of Physics, University of Alberta, Edmonton, AB, Canada
| | - Marco A. Deriu
- PolitoMed Lab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, 10129 Turin, Italy
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20
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Fanani ML, Nocelli NE, Zulueta Díaz YDLM. What can we learn about amphiphile-membrane interaction from model lipid membranes? BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2022; 1864:183781. [PMID: 34555419 DOI: 10.1016/j.bbamem.2021.183781] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 08/30/2021] [Accepted: 09/14/2021] [Indexed: 10/20/2022]
Abstract
Surface-active amphiphiles find applications in a wide range of areas of industry such as agrochemicals, personal care, and pharmaceuticals. In many of these applications, interaction with cell membranes is a key factor for achieving their purpose. How do amphiphiles interact with lipid membranes? What are their bases for membrane specificity? Which biophysical properties of membranes are susceptible to modulation by amphiphilic membrane-effectors? What aspects of this interaction are important for performing their function? In our work on membrane biophysics over the years, questions like these have arisen and we now share some of our findings and discuss them in this review. This topic was approached focusing on the membrane properties and their alterations rather than on the amphiphile structure requirements for their interaction. Here, we do not aim to provide a comprehensive list of the modes of action of amphiphiles of biological interest but to help in understanding them.
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Affiliation(s)
- Maria Laura Fanani
- Departamento de Química Biológica Ranwel Caputto, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina; Centro de Investigaciones en Química Biológica de Córdoba (CIQUIBIC), CONICET, Córdoba, Argentina.
| | - Natalia E Nocelli
- Departamento de Química Biológica Ranwel Caputto, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina; Centro de Investigaciones en Química Biológica de Córdoba (CIQUIBIC), CONICET, Córdoba, Argentina
| | - Yenisleidy de Las Mercedes Zulueta Díaz
- Departamento de Química Biológica Ranwel Caputto, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina; Centro de Investigaciones en Química Biológica de Córdoba (CIQUIBIC), CONICET, Córdoba, Argentina
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21
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Surface Properties of Synaptosomes in the Presence of L-Glutamic and Kainic Acids: In Vitro Alteration of the ATPase and Acetylcholinesterase Activities. MEMBRANES 2021; 11:membranes11120987. [PMID: 34940488 PMCID: PMC8708669 DOI: 10.3390/membranes11120987] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 12/12/2021] [Accepted: 12/14/2021] [Indexed: 11/23/2022]
Abstract
Morphologically and functionally identical to brain synapses, the nerve ending particles synaptosomes are biochemically derived membrane structures responsible for the transmission of neural information. Their surface and mechanical properties, measured in vitro, provide useful information about the functional activity of synapses in the brain in vivo. Glutamate and kainic acid are of particular interest because of their role in brain pathology (including causing seizure, migraine, ischemic stroke, aneurysmal subarachnoid hemorrhage, intracerebral hematoma, traumatic brain injury and stroke). The effects of the excitatory neurotransmitter L-glutamic acid and its agonist kainic acid are tested on Na+, K+-ATPase and Mg2+-ATPase activities in synaptic membranes prepared from the cerebral cortex of rat brain tissue. The surface parameters of synaptosome preparations from the cerebral cortex in the presence of L-glutamic and kainic acids are studied by microelectrophoresis for the first time. The studied neurotransmitters promote a significant increase in the electrophoretic mobility and surface electrical charge of synaptosomes at 1–4 h after isolation. The measured decrease in the bending modulus of model bimolecular membranes composed of monounsaturated lipid 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine provides evidence for softer membranes in the presence of L-glutamate. Kainic acid does not affect membrane mechanical stability even at ten-fold higher concentrations. Both the L-glutamic and kainic acids reduce acetylcholinesterase activity and deviation from the normal functions of neurotransmission in synapses is presumed. The presented results regarding the modulation of the enzyme activity of synaptic membranes and surface properties of synaptosomes are expected by biochemical and biophysical studies to contribute to the elucidation of the molecular mechanisms of neurotransmitters/agonists’ action on membranes.
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22
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Abstract
The cell membrane serves as a barrier that restricts the rate of exchange of diffusible molecules. Tension in the membrane regulates many crucial cell functions involving shape changes and motility, cell signaling, endocytosis, and mechanosensation. Tension reflects the forces contributed by the lipid bilayer, the cytoskeleton, and the extracellular matrix. With a fluid-like bilayer model, membrane tension is presumed uniform and hence propagated instantaneously. In this review, we discuss techniques to measure the mean membrane tension and how to resolve the stresses in different components and consider the role of bilayer heterogeneity.
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Affiliation(s)
- Pei-Chuan Chao
- Department of Civil, Structural and Environmental Engineering, University at Buffalo, The State University of New York, Buffalo, NY, United States
| | - Frederick Sachs
- Department of Physiology and Biophysics, University at Buffalo, The State University of New York, Buffalo, NY, United States.
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23
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Mishra M, Kapoor S. Modulation of a host's cell membrane nano-environment by mycobacterial glycolipids: involvement of PI(4,5)P 2 signaling lipid? Faraday Discuss 2021; 232:295-316. [PMID: 34542111 DOI: 10.1039/d0fd00051e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Virulence-associated glycolipids from Mycobacterium tuberculosis (Mtb) act as effector molecules during infection-in addition to proteins. Upon insertion, they alter the host cell's membrane properties modifying the host's functions to aid Mtb survival and disease course. Here we combine tether force experiments and microscopy to reveal previously unknown insights on the potential involvement of the phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) lipid in the Mtb lipid-host interaction landscape. Our data shows that Mtb lipids, having different structural and chemical make-up, distinctly alter a host's PI(4,5)P2 membrane abundance/organization and PI(4,5)P2-actin colocalization, thus impacting the plasma membrane-cytoskeletal adhesion forces. Combined with our previous findings that underscore the role of exogenous Mtb lipids in remodeling host plasma membrane organization and mechanics, this work builds upon a lipid-centric view of tubercular infections. Dynamically changing a host's plasma membrane lipid content - in response to virulent lipids - might represent a so far unexplored mechanism invoked by Mtb to modulate the host cell's adhesive properties to escape immune surveillance. These findings will deepen our collective understanding of the functional role of Mtb lipids in hijacking the host cell processes amenable to pharmacological inhibition.
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Affiliation(s)
- Manjari Mishra
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai 400076, India.
| | - Shobhna Kapoor
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai 400076, India.
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24
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Kumari P, Faraone A, Kelley EG, Benedetto A. Stiffening Effect of the [Bmim][Cl] Ionic Liquid on the Bending Dynamics of DMPC Lipid Vesicles. J Phys Chem B 2021; 125:7241-7250. [PMID: 34169716 PMCID: PMC8279542 DOI: 10.1021/acs.jpcb.1c01347] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The elastic properties of the cellular lipid membrane play a crucial role for life. Their alteration can lead to cell malfunction, and in turn, being able to control them holds the promise of effective therapeutic and diagnostic approaches. In this context, due to their proven strong interaction with lipid bilayers, ionic liquids (ILs)-a vast class of organic electrolytes-may play an important role. This work focuses on the effect of the model imidazolium-IL [bmim][Cl] on the bending modulus of DMPC lipid vesicles, a basic model of cellular lipid membranes. Here, by combining small-angle neutron scattering and neutron spin-echo spectroscopy, we show that the IL, dispersed at low concentrations at the bilayer-water interface, (i) diffuses into the lipid region, accounting for five IL-cations for every 11 lipids, and (ii) causes an increase of the lipid bilayer bending modulus, up to 60% compared to the neat lipid bilayer at 40 °C.
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Affiliation(s)
- Pallavi Kumari
- Department of Sciences, University of Roma Tre, 00146 Rome, Italy.,School of Physics and Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Dublin 4, Ireland
| | - Antonio Faraone
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Elizabeth G Kelley
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Antonio Benedetto
- Department of Sciences, University of Roma Tre, 00146 Rome, Italy.,School of Physics and Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Dublin 4, Ireland.,Laboratory for Neutron Scattering, Paul Scherrer Institute, 5232 Villigen, Switzerland
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25
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Alimohamadi H, Bell MK, Halpain S, Rangamani P. Mechanical Principles Governing the Shapes of Dendritic Spines. Front Physiol 2021; 12:657074. [PMID: 34220531 PMCID: PMC8242199 DOI: 10.3389/fphys.2021.657074] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 05/13/2021] [Indexed: 02/04/2023] Open
Abstract
Dendritic spines are small, bulbous protrusions along the dendrites of neurons and are sites of excitatory postsynaptic activity. The morphology of spines has been implicated in their function in synaptic plasticity and their shapes have been well-characterized, but the potential mechanics underlying their shape development and maintenance have not yet been fully understood. In this work, we explore the mechanical principles that could underlie specific shapes using a minimal biophysical model of membrane-actin interactions. Using this model, we first identify the possible force regimes that give rise to the classic spine shapes-stubby, filopodia, thin, and mushroom-shaped spines. We also use this model to investigate how the spine neck might be stabilized using periodic rings of actin or associated proteins. Finally, we use this model to predict that the cooperation between force generation and ring structures can regulate the energy landscape of spine shapes across a wide range of tensions. Thus, our study provides insights into how mechanical aspects of actin-mediated force generation and tension can play critical roles in spine shape maintenance.
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Affiliation(s)
- Haleh Alimohamadi
- Department of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, CA, United States
| | - Miriam K. Bell
- Department of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, CA, United States
| | - Shelley Halpain
- Sanford Consortium for Regenerative Medicine, La Jolla, CA, United States
- Section of Neurobiology, Division of Biological Sciences, University of California, San Diego, La Jolla, CA, United States
| | - Padmini Rangamani
- Department of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, CA, United States
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26
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Biomechanics of Neutrophil Tethers. Life (Basel) 2021; 11:life11060515. [PMID: 34073130 PMCID: PMC8230032 DOI: 10.3390/life11060515] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 05/22/2021] [Accepted: 05/25/2021] [Indexed: 12/11/2022] Open
Abstract
Leukocytes, including neutrophils, propelled by blood flow, can roll on inflamed endothelium using transient bonds between selectins and their ligands, and integrins and their ligands. When such receptor–ligand bonds last long enough, the leukocyte microvilli become extended and eventually form thin, 20 µm long tethers. Tether formation can be observed in blood vessels in vivo and in microfluidic flow chambers. Tethers can also be extracted using micropipette aspiration, biomembrane force probe, optical trap, or atomic force microscopy approaches. Here, we review the biomechanical properties of leukocyte tethers as gleaned from such measurements and discuss the advantages and disadvantages of each approach. We also review and discuss viscoelastic models that describe the dependence of tether formation on time, force, rate of loading, and cell activation. We close by emphasizing the need to combine experimental observations with quantitative models and computer simulations to understand how tether formation is affected by membrane tension, membrane reservoir, and interactions of the membrane with the cytoskeleton.
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27
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Gómez F, Silva LS, Araújo GRDS, Frases S, Pinheiro AAS, Agero U, Pontes B, Viana NB. Effect of cell geometry in the evaluation of erythrocyte viscoelastic properties. Phys Rev E 2021; 101:062403. [PMID: 32688571 DOI: 10.1103/physreve.101.062403] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 05/11/2020] [Indexed: 11/07/2022]
Abstract
The red blood cell membrane-cytoskeleton is a complex structure mainly responsible for giving the cell rigidity and shape. It also provides the erythrocyte with the ability to pass through narrow capillaries of the vertebrate blood circulatory system. Although the red blood cell viscoelastic properties have been extensively studied, reported experimental data differ by up to three orders of magnitude. This could be attributed to the natural cell variability, to the different techniques employed, and also to the models used for the cell response, which are highly dependent on cell geometry. Here, we use two methodologies based on optical tweezers to investigate the viscoelastic behavior of healthy human red blood cells, one applying small cell deformations (microrheology) and another imposing large deformations (tether extraction). We also establish a defocusing microscopy-based method to characterize the cell geometry and thus the erythrocyte form factor, an essential parameter that allows comparisons among the viscoelastic properties at different conditions. Moreover, for small deformations, a soft glassy rheology model is used to discuss the results, while for large deformations two surface shear moduli and one surface viscosity are determined, together with the surface tension and bending modulus of the erythrocyte membrane lipid component. We also show that F-actin is not detected in tethers, although the erythrocyte membrane has physical properties like those of other adherent cells, known to have tethers containing F-actin inside. Altogether, our results show good agreement with the reported literature and we argue that, to properly compare the viscoelastic properties of red blood cells in different situations, the task of cell geometry characterization must be accomplished. This may be especially important when the influence of agents, like the malaria parasite, induces changes in both the geometry and chemical constituents of the erythrocyte membrane. Together, the new methodologies and procedures used in this study would allow the erythrocyte community to better explore the mechanical behavior of red blood cells and may be useful to characterize erythrocyte viscoelasticity changes in several blood diseases.
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Affiliation(s)
- Fran Gómez
- Instituto de Física, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, 21941-972, Brazil.,LPO-COPEA, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, 21941-902, Brazil.,CENABIO - Centro Nacional de Biologia Estrutural e Bioimagem, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, 21941-902, Brazil
| | - Leandro S Silva
- Instituto de Biofísica Carlos Chagas Filho, Rio de Janeiro, Rio de Janeiro, 21941-901, Brazil
| | | | - Susana Frases
- Instituto de Biofísica Carlos Chagas Filho, Rio de Janeiro, Rio de Janeiro, 21941-901, Brazil
| | - Ana Acacia S Pinheiro
- Instituto de Biofísica Carlos Chagas Filho, Rio de Janeiro, Rio de Janeiro, 21941-901, Brazil
| | - Ubirajara Agero
- Instituto de Ciências Exatas, Departamento de Física, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, 31270-901, Brazil
| | - Bruno Pontes
- Instituto de Física, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, 21941-972, Brazil.,LPO-COPEA, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, 21941-902, Brazil.,CENABIO - Centro Nacional de Biologia Estrutural e Bioimagem, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, 21941-902, Brazil
| | - Nathan Bessa Viana
- Instituto de Física, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, 21941-972, Brazil.,LPO-COPEA, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, 21941-902, Brazil.,CENABIO - Centro Nacional de Biologia Estrutural e Bioimagem, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, 21941-902, Brazil
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28
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Dudiki T, Mahajan G, Liu H, Zhevlakova I, Bertagnolli C, Nascimento DW, Kothapalli CR, Byzova TV. Kindlin3 regulates biophysical properties and mechanics of membrane to cortex attachment. Cell Mol Life Sci 2021; 78:4003-4018. [PMID: 33783564 PMCID: PMC11071771 DOI: 10.1007/s00018-021-03817-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 03/01/2021] [Accepted: 03/18/2021] [Indexed: 12/19/2022]
Abstract
Kindlin3 (K3), a FERM domain containing protein expressed in hematopoietic cells controls integrin activation and thus hemostatic and inflammatory responses. However, its role in the mechanics of plasma membrane remains unclear. Here, we show that genetic knockout of K3 in microglia and macrophages resulted in defective plasma membrane tension and membrane blebbing. Atomic force microscopy (AFM) of K3-deficient cells revealed a significant loss in membrane-to-cortex attachment (MCA), and consequently reduced membrane tension. This loss in MCA is amplified by the mislocalization of the cell cortex proteins-ezrin, radixin, and moesin (ERM)-to the plasma membrane of microglia and macrophages. Re-expression of K3 in K3-deficient macrophages rescued the defects and localization of ERMs implying a key role for K3 in MCA. Analysis of two K3 mutants, K3int affecting integrin binding and activation, and K3pxn/act disrupting binding to paxillin and actin but not integrin functions, demonstrated that the role of K3 in membrane mechanics is separate from integrin activation. The K3pxn/act mutant substantially diminished both membrane tension and Yes-associated protein (YAP) translocation to the nucleus, while preserving integrin activation, cell spreading, and migration. Together, our results show that K3 coordinates membrane mechanics, ERM protein recruitment to the membrane, and YAP translocation by linking integrin at the membrane to paxillin and actin of the cytoskeleton. This novel function of K3 is distinct from its role in integrin activation.
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Affiliation(s)
- Tejasvi Dudiki
- Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Gautam Mahajan
- Chemical and Biomedical Engineering Department, Washkewicz College of Engineering, Cleveland State University, Cleveland, OH, 44115, USA
| | - Huan Liu
- Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Irina Zhevlakova
- Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Chase Bertagnolli
- Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44195, USA
| | | | - Chandrasekhar R Kothapalli
- Chemical and Biomedical Engineering Department, Washkewicz College of Engineering, Cleveland State University, Cleveland, OH, 44115, USA.
| | - Tatiana V Byzova
- Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44195, USA.
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29
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Bonilla-Quintana M, Wörgötter F. Exploring new roles for actin upon LTP induction in dendritic spines. Sci Rep 2021; 11:7072. [PMID: 33782451 PMCID: PMC8007616 DOI: 10.1038/s41598-021-86367-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 03/15/2021] [Indexed: 01/21/2023] Open
Abstract
Dendritic spines, small protrusions of the dendrites, enlarge upon LTP induction, linking morphological and functional properties. Although the role of actin in spine enlargement has been well studied, little is known about its relationship with mechanical membrane properties, such as membrane tension, which is involved in many cell processes, like exocytosis. Here, we use a 3D model of the dendritic spine to investigate how polymerization of actin filaments can effectively elevate the membrane tension to trigger exocytosis in a domain close to the tip of the spine. Moreover, we show that the same pool of actin promotes full membrane fusion after exocytosis and spine stabilization.
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30
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Protocol to measure the membrane tension and bending modulus of cells using optical tweezers and scanning electron microscopy. STAR Protoc 2021; 2:100283. [PMID: 33532732 PMCID: PMC7821041 DOI: 10.1016/j.xpro.2020.100283] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The elastic properties of cell membranes, particularly the membrane tension and bending modulus, are known to be key regulators of cellular functions. Here, we present a correlative and integrated tool based on optical tweezers and scanning electron microscopy to accurately determine these properties in a variety of cell types. Although there are intrinsic difficulties associated with correlative experiments, we believe that the methods presented can be considered a suitable protocol for determining the elastic properties of cell membranes. For complete details on the use and execution of this protocol, please refer to Soares et al. (2020). Protocol to obtain the membrane tension and bending modulus of cells Detailed procedures to measure the membrane tether force with optical tweezers Correlative optical tweezers-scanning electron microscopy to measure the tether radius
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31
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Wang JD, Qu CT, Song SF. Temperature-induced changes in the proteome of Pseudomonas aeruginosa during petroleum hydrocarbon degradation. Arch Microbiol 2021; 203:2463-2473. [PMID: 33677632 DOI: 10.1007/s00203-021-02211-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 12/27/2020] [Accepted: 02/09/2021] [Indexed: 10/22/2022]
Abstract
Petroleum hydrocarbon contaminants, which are among the most serious pollutants in the petroleum industry, can be degraded sufficiently by Pseudomonas aeruginosa. However, temperature-induced stress will severely inhibit this biodegradation. In this study, the proteome of P. aeruginosa P6 at 25 °C, 43 °C and 37 °C was used to examine the impact of temperature on the molecular mechanism of biodegradation of petroleum hydrocarbon by P. aeruginosa P6. Differentially expressed proteins were identified by iTRAQ technology, and the functions of these proteins were identified by bioinformatic analysis. The impact of 25 °C and 43 °C on cellular processes has also been discussed. The results showed that the expression of proteins in chemotaxis toward petroleum hydrocarbons, terminal oxidation of aromatic rings in petroleum hydrocarbons and trans-membrane transport of fatty acids and nutriments were clearly inhibited under 25 °C condition. The expression of proteins in chemotaxis, emulsification, adhesion and terminal oxidation of petroleum hydrocarbons; catalysis of fatty alcohols and fatty aldehydes; trans-membrane transport of nutriments and β-oxidation were clearly inhibited under 43 °C condition.
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Affiliation(s)
- Jun-Di Wang
- College of Chemistry and Chemical Engineering, Xi'an Shiyou University, Xi'an, People's Republic of China. .,School of Human Settlements and Civil Engineering, Xi'an Jiaotong University, Xi'an, People's Republic of China. .,Shaanxi Key Laboratory of Environmental Pollution Control Technology and Reservoir Protection of Oilfield, Xi'an Shiyou University, Xi'an, 710065, People's Republic of China. .,State Key Laboratory of Petroleum and Petrochemical Pollution Control and Treatment, Beijing, 102206, People's Republic of China.
| | - Cheng-Tun Qu
- College of Chemistry and Chemical Engineering, Xi'an Shiyou University, Xi'an, People's Republic of China.,Shaanxi Key Laboratory of Environmental Pollution Control Technology and Reservoir Protection of Oilfield, Xi'an Shiyou University, Xi'an, 710065, People's Republic of China.,State Key Laboratory of Petroleum and Petrochemical Pollution Control and Treatment, Beijing, 102206, People's Republic of China
| | - Shao-Fu Song
- College of Chemistry and Chemical Engineering, Xi'an Shiyou University, Xi'an, People's Republic of China.,Shaanxi Key Laboratory of Environmental Pollution Control Technology and Reservoir Protection of Oilfield, Xi'an Shiyou University, Xi'an, 710065, People's Republic of China.,State Key Laboratory of Petroleum and Petrochemical Pollution Control and Treatment, Beijing, 102206, People's Republic of China
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32
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Affiliation(s)
- Chandra Has
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai, India
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33
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Lenton ICD, Scott EK, Rubinsztein-Dunlop H, Favre-Bulle IA. Optical Tweezers Exploring Neuroscience. Front Bioeng Biotechnol 2020; 8:602797. [PMID: 33330435 PMCID: PMC7732537 DOI: 10.3389/fbioe.2020.602797] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 11/04/2020] [Indexed: 12/30/2022] Open
Abstract
Over the past decade, optical tweezers (OT) have been increasingly used in neuroscience for studies of molecules and neuronal dynamics, as well as for the study of model organisms as a whole. Compared to other areas of biology, it has taken much longer for OT to become an established tool in neuroscience. This is, in part, due to the complexity of the brain and the inherent difficulties in trapping individual molecules or manipulating cells located deep within biological tissue. Recent advances in OT, as well as parallel developments in imaging and adaptive optics, have significantly extended the capabilities of OT. In this review, we describe how OT became an established tool in neuroscience and we elaborate on possible future directions for the field. Rather than covering all applications of OT to neurons or related proteins and molecules, we focus our discussions on studies that provide crucial information to neuroscience, such as neuron dynamics, growth, and communication, as these studies have revealed meaningful information and provide direction for the field into the future.
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Affiliation(s)
- Isaac C. D. Lenton
- School of Mathematics and Physics, The University of Queensland, Brisbane, QLD, Australia
| | - Ethan K. Scott
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD, Australia
| | | | - Itia A. Favre-Bulle
- School of Mathematics and Physics, The University of Queensland, Brisbane, QLD, Australia
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD, Australia
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34
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Gensbittel V, Kräter M, Harlepp S, Busnelli I, Guck J, Goetz JG. Mechanical Adaptability of Tumor Cells in Metastasis. Dev Cell 2020; 56:164-179. [PMID: 33238151 DOI: 10.1016/j.devcel.2020.10.011] [Citation(s) in RCA: 94] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 09/18/2020] [Accepted: 10/16/2020] [Indexed: 12/12/2022]
Abstract
The most dangerous aspect of cancer lies in metastatic progression. Tumor cells will successfully form life-threatening metastases when they undergo sequential steps along a journey from the primary tumor to distant organs. From a biomechanics standpoint, growth, invasion, intravasation, circulation, arrest/adhesion, and extravasation of tumor cells demand particular cell-mechanical properties in order to survive and complete the metastatic cascade. With metastatic cells usually being softer than their non-malignant counterparts, high deformability for both the cell and its nucleus is thought to offer a significant advantage for metastatic potential. However, it is still unclear whether there is a finely tuned but fixed mechanical state that accommodates all mechanical features required for survival throughout the cascade or whether tumor cells need to dynamically refine their properties and intracellular components at each new step encountered. Here, we review the various mechanical requirements successful cancer cells might need to fulfill along their journey and speculate on the possibility that they dynamically adapt their properties accordingly. The mechanical signature of a successful cancer cell might actually be its ability to adapt to the successive microenvironmental constraints along the different steps of the journey.
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Affiliation(s)
- Valentin Gensbittel
- INSERM UMR_S1109, Tumor Biomechanics, Strasbourg, France; Université de Strasbourg, Strasbourg, France; Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France
| | - Martin Kräter
- Max Planck Institute for the Science of Light & Max-Planck-Zentrum für Physik und Medizin, Erlangen, Germany
| | - Sébastien Harlepp
- INSERM UMR_S1109, Tumor Biomechanics, Strasbourg, France; Université de Strasbourg, Strasbourg, France; Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France
| | - Ignacio Busnelli
- INSERM UMR_S1109, Tumor Biomechanics, Strasbourg, France; Université de Strasbourg, Strasbourg, France; Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France
| | - Jochen Guck
- Max Planck Institute for the Science of Light & Max-Planck-Zentrum für Physik und Medizin, Erlangen, Germany.
| | - Jacky G Goetz
- INSERM UMR_S1109, Tumor Biomechanics, Strasbourg, France; Université de Strasbourg, Strasbourg, France; Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France.
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35
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Sitarska E, Diz-Muñoz A. Pay attention to membrane tension: Mechanobiology of the cell surface. Curr Opin Cell Biol 2020; 66:11-18. [PMID: 32416466 PMCID: PMC7594640 DOI: 10.1016/j.ceb.2020.04.001] [Citation(s) in RCA: 97] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 04/01/2020] [Accepted: 04/02/2020] [Indexed: 02/09/2023]
Abstract
The cell surface is a mechanobiological unit that encompasses the plasma membrane, its interacting proteins, and the complex underlying cytoskeleton. Recently, attention has been directed to the mechanics of the plasma membrane, and in particular membrane tension, which has been linked to diverse cellular processes such as cell migration and membrane trafficking. However, how tension across the plasma membrane is regulated and propagated is still not completely understood. Here, we review recent efforts to study the interplay between membrane tension and the cytoskeletal machinery and how they control cell form and function. We focus on factors that have been proposed to affect the propagation of membrane tension and as such could determine whether it can act as a global or local regulator of cell behavior. Finally, we discuss the limitations of the available tool kit as new approaches that reveal its dynamics in cells are needed to decipher how membrane tension regulates diverse cellular processes.
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Affiliation(s)
- Ewa Sitarska
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117, Heidelberg, Germany
| | - Alba Diz-Muñoz
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117, Heidelberg, Germany.
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36
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Rong N, Zhang M, Wang Y, Wu H, Qi H, Fu X, Li D, Yang C, Wang Y, Fan Z. Effects of extracellular matrix rigidity on sonoporation facilitated by targeted microbubbles: Bubble attachment, bubble dynamics, and cell membrane permeabilization. ULTRASONICS SONOCHEMISTRY 2020; 67:105125. [PMID: 32298974 DOI: 10.1016/j.ultsonch.2020.105125] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 02/19/2020] [Accepted: 04/07/2020] [Indexed: 06/11/2023]
Abstract
In this study, we investigated the effects of extracellular matrix rigidity, an important physical property of microenvironments regulating cell morphology and functions, on sonoporation facilitated by targeted microbubbles, highlighting the role of microbubbles. We conducted mechanistic studies at the cellular level on physiologically relevant soft and rigid substrates. By developing a unique imaging strategy, we first resolved details of the 3D attachment configurations between targeted microbubbles and cell membrane. High-speed video microscopy then unveiled bubble dynamics driven by a single ultrasound pulse. Finally, we evaluated the cell membrane permeabilization using a small molecule model drug. Our results demonstrate that: (1) stronger targeted microbubble attachment was formed for cells cultured on the rigid substrate, while six different attachment configurations were revealed in total; (2) more violent bubble oscillation was observed for cells cultured on the rigid substrate, while one third of bubbles attached to cells on the soft substrate exhibited deformation shortly after ultrasound was turned off; (3) higher acoustic pressure was needed to permeabilize the cell membrane for cells on the soft substrate, while under the same ultrasound condition, acoustically-activated microbubbles generated larger pores as compared to cells cultured on the soft substrate. The current findings provide new insights to understand the underlying mechanisms of sonoporation in a physiologically relevant context and may be useful for the clinical translation of sonoporation.
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Affiliation(s)
- Ning Rong
- Department of Biomedical Engineering, School of Precision Instruments and Opto-Electronics Engineering, Tianjin University, Tianjin 300072, China
| | - Meiru Zhang
- Department of Biomedical Engineering, School of Precision Instruments and Opto-Electronics Engineering, Tianjin University, Tianjin 300072, China
| | - Yulin Wang
- Department of Biomedical Engineering, School of Precision Instruments and Opto-Electronics Engineering, Tianjin University, Tianjin 300072, China
| | - Hao Wu
- State Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin 300072, China
| | - Hui Qi
- State Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin 300072, China
| | - Xing Fu
- State Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin 300072, China
| | - Dachao Li
- State Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin 300072, China
| | - Chunmei Yang
- Department of Biomedical Engineering, School of Precision Instruments and Opto-Electronics Engineering, Tianjin University, Tianjin 300072, China
| | - Yan Wang
- Department of Biomedical Engineering, School of Precision Instruments and Opto-Electronics Engineering, Tianjin University, Tianjin 300072, China
| | - Zhenzhen Fan
- Department of Biomedical Engineering, School of Precision Instruments and Opto-Electronics Engineering, Tianjin University, Tianjin 300072, China; State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190, China.
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37
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Recent Experiments Support a Microemulsion Origin of Plasma Membrane Domains: Dependence of Domain Size on Physical Parameters. MEMBRANES 2020; 10:membranes10080167. [PMID: 32731358 PMCID: PMC7465459 DOI: 10.3390/membranes10080167] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 07/21/2020] [Accepted: 07/24/2020] [Indexed: 11/17/2022]
Abstract
It is widely, but not universally, believed that the lipids of the plasma membrane are not uniformly distributed, but that “rafts” of sphingolipids and cholesterol float in a “sea” of unsaturated lipids. The physical origin of such heterogeneities is often attributed to a phase coexistence between the two different domains. We argue that this explanation is untenable for several reasons. Further, we note that the results of recent experiments are inconsistent with this picture. However, they are quite consistent with an alternate explanation, namely, that the plasma membrane is a microemulsion of the two kinds of regions. To show this, we briefly review a simplified version of this theory and its phase diagram. We also explicate the dependence of the predicted domain size on four physical parameters. They are the energy cost of gradients in the composition, the spontaneous curvature of the membrane, its bending modulus and its surface tension. Taking values of the latter two from experiment, we obtain domain sizes for several different cell types that vary from 58 to 88 nm.
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38
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Soares J, Araujo GRDS, Santana C, Matias D, Moura-Neto V, Farina M, Frases S, Viana NB, Romão L, Nussenzveig HM, Pontes B. Membrane Elastic Properties During Neural Precursor Cell Differentiation. Cells 2020; 9:E1323. [PMID: 32466390 PMCID: PMC7349228 DOI: 10.3390/cells9061323] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 05/15/2020] [Accepted: 05/17/2020] [Indexed: 02/08/2023] Open
Abstract
Neural precursor cells differentiate into several cell types that display distinct functions. However, little is known about how cell surface mechanics vary during the differentiation process. Here, by precisely measuring membrane tension and bending modulus, we map their variations and correlate them with changes in neural precursor cell morphology along their distinct differentiation fates. Both cells maintained in culture as neural precursors as well as those plated in neurobasal medium reveal a decrease in membrane tension over the first hours of culture followed by stabilization, with no change in bending modulus. During astrocyte differentiation, membrane tension initially decreases and then increases after 72 h, accompanied by consolidation of glial fibrillary acidic protein expression and striking actin reorganization, while bending modulus increases following observed alterations. For oligodendrocytes, the changes in membrane tension are less abrupt over the first hours, but their values subsequently decrease, correlating with a shift from oligodendrocyte marker O4 to myelin basic protein expressions and a remarkable actin reorganization, while bending modulus remains constant. Oligodendrocytes at later differentiation stages show membrane vesicles with similar membrane tension but higher bending modulus as compared to the cell surface. Altogether, our results display an entire spectrum of how membrane elastic properties are varying, thus contributing to a better understanding of neural differentiation from a mechanobiological perspective.
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Affiliation(s)
- Juliana Soares
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil; (J.S.); (C.S.); (D.M.); (V.M.-N.); (M.F.); (L.R.)
- Centro Nacional de Biologia Estrutural e Bioimagem (CENABIO), Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil;
| | - Glauber R. de S. Araujo
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil; (G.R.d.S.A.); (S.F.)
| | - Cintia Santana
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil; (J.S.); (C.S.); (D.M.); (V.M.-N.); (M.F.); (L.R.)
| | - Diana Matias
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil; (J.S.); (C.S.); (D.M.); (V.M.-N.); (M.F.); (L.R.)
- Instituto Estadual do Cérebro Paulo Niemeyer, Secretaria de Estado de Saúde, Rio de Janeiro, RJ 20231-092, Brazil
| | - Vivaldo Moura-Neto
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil; (J.S.); (C.S.); (D.M.); (V.M.-N.); (M.F.); (L.R.)
- Instituto Estadual do Cérebro Paulo Niemeyer, Secretaria de Estado de Saúde, Rio de Janeiro, RJ 20231-092, Brazil
| | - Marcos Farina
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil; (J.S.); (C.S.); (D.M.); (V.M.-N.); (M.F.); (L.R.)
| | - Susana Frases
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil; (G.R.d.S.A.); (S.F.)
| | - Nathan B. Viana
- Centro Nacional de Biologia Estrutural e Bioimagem (CENABIO), Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil;
- Instituto de Física, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-942, Brazil
| | - Luciana Romão
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil; (J.S.); (C.S.); (D.M.); (V.M.-N.); (M.F.); (L.R.)
| | - H. Moysés Nussenzveig
- Centro Nacional de Biologia Estrutural e Bioimagem (CENABIO), Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil;
- Instituto de Física, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-942, Brazil
| | - Bruno Pontes
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil; (J.S.); (C.S.); (D.M.); (V.M.-N.); (M.F.); (L.R.)
- Centro Nacional de Biologia Estrutural e Bioimagem (CENABIO), Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil;
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39
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Li J, Wijeratne SS, Nelson TE, Lin TC, He X, Feng X, Nikoloutsos N, Fang R, Jiang K, Lian I, Kiang CH. Dependence of Membrane Tether Strength on Substrate Rigidity Probed by Single-Cell Force Spectroscopy. J Phys Chem Lett 2020; 11:4173-4178. [PMID: 32356665 DOI: 10.1021/acs.jpclett.0c00730] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Substrate rigidity modulates cell mechanics, which affect cell migration and proliferation. Quantifying the effects of substrate rigidity on cancer cell mechanics requires a quantifiable parameter that can be measured for individual cells, as well as a substrate platform with rigidity being the only variable. Here we used single-cell force spectroscopy to pull cancer cells on substrates varying only in rigidity, and extracted a parameter from the force-distance curves to be used to quantify the properties of membrane tethers. Our results showed that tether force increases with substrate rigidity until it reaches its asymptotic limit. The variations are similar for all three cancer cell lines studied, and the largest change occurs in the rigidity regions of softer tissues, indicating a universal response of cancer cell elasticity to substrate rigidity.
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Affiliation(s)
- Jingqiang Li
- Department of Physics and Astronomy, Rice University, Houston, Texas 77005, United States
| | - Sithara S Wijeratne
- Department of Physics and Astronomy, Rice University, Houston, Texas 77005, United States
| | - Tyler E Nelson
- Department of Physics and Astronomy, Rice University, Houston, Texas 77005, United States
- Department of Biology, Lamar University, Beaumont, Texas 77710, United States
| | - Tsung-Cheng Lin
- Department of Physics and Astronomy, Rice University, Houston, Texas 77005, United States
| | - Xin He
- Department of Physics and Astronomy, Rice University, Houston, Texas 77005, United States
| | - Xuewen Feng
- Department of Physics and Astronomy, Rice University, Houston, Texas 77005, United States
| | - Nicolas Nikoloutsos
- Department of Biology, Lamar University, Beaumont, Texas 77710, United States
| | - Raymond Fang
- Department of Physics and Astronomy, Rice University, Houston, Texas 77005, United States
| | - Kevin Jiang
- Department of Physics and Astronomy, Rice University, Houston, Texas 77005, United States
| | - Ian Lian
- Department of Biology, Lamar University, Beaumont, Texas 77710, United States
| | - Ching-Hwa Kiang
- Department of Physics and Astronomy, Rice University, Houston, Texas 77005, United States
- Department of Bioengineering, Rice University, Houston, Texas 77005, United States
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40
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Anthonisen M, Zhang Y, Hussain Sangji M, Grütter P. Quantifying bio-filament morphology below the diffraction limit of an optical microscope using out-of-focus images. APPLIED OPTICS 2020; 59:2914-2923. [PMID: 32225847 DOI: 10.1364/ao.388265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 02/24/2020] [Indexed: 06/10/2023]
Abstract
A method to measure the dimensions of objects below the optical diffraction limit using diffraction analysis of out-of-focus bright-field images is presented. The method relies on the comparison of the diffraction patterns of an object of unknown size to those of calibration objects of known size. Correlative scanning electron microscope measurements are used to demonstrate the applicability of this method to measure 100 nm microbeads as well as objects with a geometry different from the calibration objects. This technique is important in the context of tethered particle experiments, in which bio-filaments are bound between a substrate and a microbead. This procedure is applied to obtain the diameters of axonal extensions or neurites that are mechanically created in samples of rat hippocampal neurons. The dependence of neurite geometry on mechanical pull speed is investigated, and the diameter is found to be rate independent.
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41
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Shadmani P, Mehrafrooz B, Montazeri A, Naghdabadi R. Protein corona impact on nanoparticle-cell interactions: toward an energy-based model of endocytosis. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:115101. [PMID: 31751982 DOI: 10.1088/1361-648x/ab5a14] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Upon incubation of nanoparticles in biological fluids, a new layer called the protein corona is formed on their surface affecting the interactions between nanoparticles and targeted cells during the endocytosis process. In the present study, a mathematical model based on the diffusion of membrane mobile receptors is proposed. Opposing the endocytosis proceeding, membrane bending and tension energies are named as resistant energy. Also, the binding energy and free-energy associated with the configurational entropy are collectively termed promoter energy. Utilizing this model, endocytosis of gold nanoparticle (GNP) is simulated to explore the biological media effect. The results reveal that there exists a nanoparticle size of 60 nm at which, the endocytosis time is at a minimum. It has been illustrated that, although for sufficiently small particles of diameter 30nm, membrane tension has a negligible contribution (<10%) in the resistant energy, it noticeably increases the endocytosis processing time for large particles. Therefore, we report several parametric studies to provide a better insight into the effects of biological media on the ingestion of nanoparticles. Through a detailed analysis of the engulfment of the nanoparticles, it is shown that the nanoparticle radius corresponding to the quickest possible ingestion time is affected in the presence of corona. Moreover, it is found that the formation of this layer does not only affect the endocytosis time but also can lead to incomplete engulfment by decreasing the ligand density on the nanoparticle surface. Use of the proposed model can play a significant role in advancing the design of nanoparticles in targeted drug delivery applications.
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Affiliation(s)
- P Shadmani
- Department of Mechanical Engineering, Sharif University of Technology, Tehran, Iran
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42
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Bonilla-Quintana M, Wörgötter F, Tetzlaff C, Fauth M. Modeling the Shape of Synaptic Spines by Their Actin Dynamics. Front Synaptic Neurosci 2020; 12:9. [PMID: 32218728 PMCID: PMC7078677 DOI: 10.3389/fnsyn.2020.00009] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Accepted: 02/24/2020] [Indexed: 01/05/2023] Open
Abstract
Dendritic spines are the morphological basis of excitatory synapses in the cortex and their size and shape correlates with functional synaptic properties. Recent experiments show that spines exhibit large shape fluctuations that are not related to activity-dependent plasticity but nonetheless might influence memory storage at their synapses. To investigate the determinants of such spontaneous fluctuations, we propose a mathematical model for the dynamics of the spine shape and analyze it in 2D-related to experimental microscopic imagery-and in 3D. We show that the spine shape is governed by a local imbalance between membrane tension and the expansive force from actin bundles that originates from discrete actin polymerization foci. Experiments have shown that only few such polymerization foci co-exist at any time in a spine, each having limited life time. The model shows that the momentarily existing set of such foci pushes the membrane along certain directions until foci are replaced and other directions may now be affected. We explore these relations in depth and use our model to predict shape and temporal characteristics of spines from the different biophysical parameters involved in actin polymerization. Approximating the model by a single recursive equation we finally demonstrate that the temporal evolution of the number of active foci is sufficient to predict the size of the model-spines. Thus, our model provides the first platform to study the relation between molecular and morphological properties of the spine with a high degree of biophysical detail.
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Affiliation(s)
- Mayte Bonilla-Quintana
- Department for Computational Neuroscience, Third Institute of Physics-Biophysics, Georg-August-University, Göttingen, Germany
| | - Florentin Wörgötter
- Department for Computational Neuroscience, Third Institute of Physics-Biophysics, Georg-August-University, Göttingen, Germany
- Bernstein Center for Computational Neuroscience, Georg-August-University, Göttingen, Germany
| | - Christian Tetzlaff
- Department for Computational Neuroscience, Third Institute of Physics-Biophysics, Georg-August-University, Göttingen, Germany
- Bernstein Center for Computational Neuroscience, Georg-August-University, Göttingen, Germany
| | - Michael Fauth
- Department for Computational Neuroscience, Third Institute of Physics-Biophysics, Georg-August-University, Göttingen, Germany
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43
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Navarro-Hernandez IC, López-Ortega O, Acevedo-Ochoa E, Cervantes-Díaz R, Romero-Ramírez S, Sosa-Hernández VA, Meza-Sánchez DE, Juárez-Vega G, Pérez-Martínez CA, Chávez-Munguía B, Galván-Hernández A, Antillón A, Ortega-Blake I, Santos-Argumedo L, Hernández-Hernández JM, Maravillas-Montero JL. Tetraspanin 33 (TSPAN33) regulates endocytosis and migration of human B lymphocytes by affecting the tension of the plasma membrane. FEBS J 2020; 287:3449-3471. [PMID: 31958362 DOI: 10.1111/febs.15216] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 11/20/2019] [Accepted: 01/16/2020] [Indexed: 12/31/2022]
Abstract
B lymphocytes are a leukocyte subset capable of developing several functions apart from differentiating into antibody-secreting cells. These processes are triggered by external activation signals that induce changes in the plasma membrane properties, regulated by the formation of different lipid-bilayer subdomains that are associated with the underlying cytoskeleton through different linker molecules, thus allowing the functional specialization of regions within the membrane. Among these, there are tetraspanin-enriched domains. Tetraspanins constitute a superfamily of transmembrane proteins that establish lateral associations with other molecules, determining its activity and localization. In this study, we identified TSPAN33 as an active player during B-lymphocyte cytoskeleton and plasma membrane-related phenomena, including protrusion formation, adhesion, phagocytosis, and cell motility. By using an overexpression model of TSPAN33 in human Raji cells, we detected a specific distribution of this protein that includes membrane microvilli, the Golgi apparatus, and extracellular vesicles. Additionally, we identified diminished phagocytic ability and altered cell adhesion properties due to the aberrant expression of integrins. Accordingly, these cells presented an enhanced migratory phenotype, as shown by its augmented chemotaxis and invasion rates. When we evaluated the mechanic response of cells during fibronectin-induced spreading, we found that TSPAN33 expression inhibited changes in roughness and membrane tension. Contrariwise, TSPAN33 knockdown cells displayed opposite phenotypes to those observed in the overexpression model. Altogether, our data indicate that TSPAN33 represents a regulatory element of the adhesion and migration of B lymphocytes, suggesting a novel implication of this tetraspanin in the control of the mechanical properties of their plasma membrane.
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Affiliation(s)
- Itze C Navarro-Hernandez
- Red de Apoyo a la Investigación, Universidad Nacional Autónoma de México e Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico.,Departamento de Biología Celular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - Orestes López-Ortega
- Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - Ernesto Acevedo-Ochoa
- Red de Apoyo a la Investigación, Universidad Nacional Autónoma de México e Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico.,Unidad de Investigación Médica en Inmunoquímica, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, Mexico
| | - Rodrigo Cervantes-Díaz
- Red de Apoyo a la Investigación, Universidad Nacional Autónoma de México e Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico.,Facultad De Medicina, Universidad Nacional Autónoma De México, Mexico
| | - Sandra Romero-Ramírez
- Red de Apoyo a la Investigación, Universidad Nacional Autónoma de México e Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico.,Facultad De Medicina, Universidad Nacional Autónoma De México, Mexico
| | - Víctor A Sosa-Hernández
- Red de Apoyo a la Investigación, Universidad Nacional Autónoma de México e Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico.,Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - David E Meza-Sánchez
- Red de Apoyo a la Investigación, Universidad Nacional Autónoma de México e Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico
| | - Guillermo Juárez-Vega
- Red de Apoyo a la Investigación, Universidad Nacional Autónoma de México e Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico
| | - César A Pérez-Martínez
- Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - Bibiana Chávez-Munguía
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | | | - Armando Antillón
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
| | - Iván Ortega-Blake
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
| | - Leopoldo Santos-Argumedo
- Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - José M Hernández-Hernández
- Departamento de Biología Celular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - José L Maravillas-Montero
- Red de Apoyo a la Investigación, Universidad Nacional Autónoma de México e Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico
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44
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Martinac B, Nikolaev YA, Silvani G, Bavi N, Romanov V, Nakayama Y, Martinac AD, Rohde P, Bavi O, Cox CD. Cell membrane mechanics and mechanosensory transduction. CURRENT TOPICS IN MEMBRANES 2020; 86:83-141. [DOI: 10.1016/bs.ctm.2020.08.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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45
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Cohen AE, Shi Z. Do Cell Membranes Flow Like Honey or Jiggle Like Jello? Bioessays 2019; 42:e1900142. [DOI: 10.1002/bies.201900142] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2019] [Revised: 10/31/2019] [Indexed: 12/24/2022]
Affiliation(s)
- Adam E. Cohen
- Departments of Chemistry and Chemical Biology and PhysicsHarvard University Cambridge MA USA
- Howard Hughes Medical Institute Chevy Chase MD USA
| | - Zheng Shi
- Departments of Chemistry and Chemical Biology and PhysicsHarvard University Cambridge MA USA
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46
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Steinkühler J, Sezgin E, Urbančič I, Eggeling C, Dimova R. Mechanical properties of plasma membrane vesicles correlate with lipid order, viscosity and cell density. Commun Biol 2019; 2:337. [PMID: 31531398 PMCID: PMC6744421 DOI: 10.1038/s42003-019-0583-3] [Citation(s) in RCA: 96] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 08/15/2019] [Indexed: 11/08/2022] Open
Abstract
Regulation of plasma membrane curvature and composition governs essential cellular processes. The material property of bending rigidity describes the energetic cost of membrane deformations and depends on the plasma membrane molecular composition. Because of compositional fluctuations and active processes, it is challenging to measure it in intact cells. Here, we study the plasma membrane using giant plasma membrane vesicles (GPMVs), which largely preserve the plasma membrane lipidome and proteome. We show that the bending rigidity of plasma membranes under varied conditions is correlated to readout from environment-sensitive dyes, which are indicative of membrane order and microviscosity. This correlation holds across different cell lines, upon cholesterol depletion or enrichment of the plasma membrane, and variations in cell density. Thus, polarity- and viscosity-sensitive probes represent a promising indicator of membrane mechanical properties. Additionally, our results allow for identifying synthetic membranes with a few well defined lipids as optimal plasma membrane mimetics.
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Affiliation(s)
- Jan Steinkühler
- Theory and Bio-Systems, Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
| | - Erdinc Sezgin
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Headley Way, Oxford, OX3 9DS UK
| | - Iztok Urbančič
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Headley Way, Oxford, OX3 9DS UK
- Condensed Matter Physics Department, “Jožef Stefan” Institute, Ljubljana, Slovenia
| | - Christian Eggeling
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Headley Way, Oxford, OX3 9DS UK
- Institute of Applied Optics Friedrich‐Schiller‐University Jena, Max-Wien Platz 4, 07743 Jena, Germany
- Leibniz Institute of Photonic Technology e.V., Albert-Einstein-Straße 9, 07745 Jena, Germany
| | - Rumiana Dimova
- Theory and Bio-Systems, Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
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47
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Sunnerberg JP, Moore P, Spedden E, Kaplan DL, Staii C. Variations of Elastic Modulus and Cell Volume with Temperature for Cortical Neurons. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:10965-10976. [PMID: 31380651 PMCID: PMC7306228 DOI: 10.1021/acs.langmuir.9b01651] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Neurons change their growth dynamics and mechanical properties in response to external stimuli such as stiffness of the local microenvironment, ambient temperature, and biochemical or geometrical guidance cues. Here we use combined atomic force microscopy (AFM) and fluorescence microscopy experiments to investigate the relationship between external temperature, soma volume, and elastic modulus for cortical neurons. We measure how changes in ambient temperature affect the volume and the mechanical properties of neuronal cells at both the bulk (elastic modulus) and local (elasticity maps) levels. The experimental data demonstrate that both the volume and the elastic modulus of the neuron soma vary with changes in temperature. Our results show a decrease by a factor of 2 in the soma elastic modulus as the ambient temperature increases from room (25 °C) to physiological (37 °C) temperature, while the volume of the soma increases by a factor of 1.3 during the same temperature sweep. Using high-resolution AFM force mapping, we measure the temperature-induced variations within different regions of the elasticity maps (low and high values of elastic modulus) and correlate these variations with the dynamics of cytoskeleton components and molecular motors. We quantify the change in soma volume with temperature and propose a simple theoretical model that relates this change with variations in soma elastic modulus. These results have significant implications for understanding neuronal development and functions, as ambient temperature, cytoskeletal dynamics, and cellular volume may change with variations in physiological conditions, for example, during tissue compression and infections in vivo as well as during cell manipulation and tissue regeneration ex vivo.
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48
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Studying nucleic envelope and plasma membrane mechanics of eukaryotic cells using confocal reflectance interferometric microscopy. Nat Commun 2019; 10:3652. [PMID: 31409824 PMCID: PMC6692322 DOI: 10.1038/s41467-019-11645-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 07/29/2019] [Indexed: 12/18/2022] Open
Abstract
Mechanical stress on eukaryotic nucleus has been implicated in a diverse range of diseases including muscular dystrophy and cancer metastasis. Today, there are very few non-perturbative methods to quantify nuclear mechanical properties. Interferometric microscopy, also known as quantitative phase microscopy (QPM), is a powerful tool for studying red blood cell biomechanics. The existing QPM tools, however, have not been utilized to study biomechanics of complex eukaryotic cells either due to lack of depth sectioning, limited phase measurement sensitivity, or both. Here, we present depth-resolved confocal reflectance interferometric microscopy as the next generation QPM to study nuclear and plasma membrane biomechanics. The proposed system features multiple confocal scanning foci, affording 1.5 micron depth-resolution and millisecond frame rate. Furthermore, a near common-path interferometer enables quantifying nanometer-scale membrane fluctuations with better than 200 picometers sensitivity. Our results present accurate quantification of nucleic envelope and plasma membrane fluctuations in embryonic stem cells. Biomechanical studies of eukaryotic cells have been limited due to low sensitivity and axial resolution in interferometric imaging. Here, the authors present depth-resolved confocal reflectance interferometric microscopy with high sensitivity and temporal resolution, which enables quantification of nucleic envelope and plasma membrane fluctuations.
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49
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Janusas T, Pilkauskas K, Janusas G, Palevicius A. Active PZT Composite Microfluidic Channel for Bioparticle Manipulation. SENSORS (BASEL, SWITZERLAND) 2019; 19:s19092020. [PMID: 31035737 PMCID: PMC6540313 DOI: 10.3390/s19092020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 04/23/2019] [Accepted: 04/26/2019] [Indexed: 05/07/2023]
Abstract
The concept of active microchannel for precise manipulation of particles in biomedicine is reported in this paper. A novel vibration-assisted thermal imprint method is proposed for effective formation of a microchannel network in the nanocomposite piezo polymer layer. In this method, bulk acoustic waves of different wavelengths excited in an imprinted microstructure enable it to function in trapping-patterning, valve, or free particle passing modes. Acoustic waves are excited using a special pattern of electrodes formed on its top surface and a single electric ground electrode formed on the bottom surface. To develop the microchannel, we first started with lead zirconate titanate (PZT) nanopowder [Pb (Zrx, Ti1-x) O3] synthesis. The PZT was further mixed with three different binding materials-polyvinyl butyral (PVB), poly(methyl methacrylate) (PMMA), and polystyrene (PS)-in benzyl alcohol to prepare a screen-printing paste. Then, using conventional screen printing techniques, three types of PZT coatings on copper foil substrates were obtained. To improve the voltage characteristics, the coatings were polarized. Their structural and chemical composition was analyzed using scanning electron microscope (SEM), while the mechanical and electrical characteristics were determined using the COMSOL Multiphysics model with experimentally obtained parameters of periodic response of the layered copper foil structure. The hydrophobic properties of the PZT composite were analyzed by measuring the contact angle between the distilled water drop and the three different polymer composites: PZT with PVB, PZT with PMMA, and PZT with PS. Finally, the behavior of the microchannel formed in the nanocomposite piezo polymer was simulated by applying electrical excitation signal on the pattern of electrodes and then analyzed experimentally using holographic interferometry. Wave-shaped vibration forms of the microchannel were obtained, thereby enabling particle manipulation.
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Affiliation(s)
- Tomas Janusas
- Faculty of Mechanical Engineering and Design, Kaunas University of Technology, Studentu str. 56, Kaunas LT-51424, Lithuania.
| | - Kestutis Pilkauskas
- Faculty of Mechanical Engineering and Design, Kaunas University of Technology, Studentu str. 56, Kaunas LT-51424, Lithuania.
| | - Giedrius Janusas
- Faculty of Mechanical Engineering and Design, Kaunas University of Technology, Studentu str. 56, Kaunas LT-51424, Lithuania.
| | - Arvydas Palevicius
- Faculty of Mechanical Engineering and Design, Kaunas University of Technology, Studentu str. 56, Kaunas LT-51424, Lithuania.
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50
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Barger SR, Reilly NS, Shutova MS, Li Q, Maiuri P, Heddleston JM, Mooseker MS, Flavell RA, Svitkina T, Oakes PW, Krendel M, Gauthier NC. Membrane-cytoskeletal crosstalk mediated by myosin-I regulates adhesion turnover during phagocytosis. Nat Commun 2019; 10:1249. [PMID: 30890704 PMCID: PMC6425032 DOI: 10.1038/s41467-019-09104-1] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 02/21/2019] [Indexed: 11/09/2022] Open
Abstract
Phagocytosis of invading pathogens or cellular debris requires a dramatic change in cell shape driven by actin polymerization. For antibody-covered targets, phagocytosis is thought to proceed through the sequential engagement of Fc-receptors on the phagocyte with antibodies on the target surface, leading to the extension and closure of the phagocytic cup around the target. We find that two actin-dependent molecular motors, class 1 myosins myosin 1e and myosin 1f, are specifically localized to Fc-receptor adhesions and required for efficient phagocytosis of antibody-opsonized targets. Using primary macrophages lacking both myosin 1e and myosin 1f, we find that without the actin-membrane linkage mediated by these myosins, the organization of individual adhesions is compromised, leading to excessive actin polymerization, slower adhesion turnover, and deficient phagocytic internalization. This work identifies a role for class 1 myosins in coordinated adhesion turnover during phagocytosis and supports a mechanism involving membrane-cytoskeletal crosstalk for phagocytic cup closure.
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Affiliation(s)
- Sarah R Barger
- Cell and Developmental Biology Department, State University of New York Upstate Medical University, Syracuse, 13210, NY, USA
| | - Nicholas S Reilly
- Department of Physics, University of Rochester, Rochester, 14627, NY, USA
| | - Maria S Shutova
- Department of Biology, University of Pennsylvania, Philadelphia, 19104, PA, USA
| | - Qingsen Li
- IFOM, FIRC Institute of Molecular Oncology, Milan, 20139, Italy
| | - Paolo Maiuri
- IFOM, FIRC Institute of Molecular Oncology, Milan, 20139, Italy
| | - John M Heddleston
- Advanced Imaging Center, Howard Hughes Medical Institute Janelia Research Campus, Ashburn, 20147, VA, USA
| | - Mark S Mooseker
- Molecular, Cellular and Developmental Biology, Yale University, New Haven, 06520, CT, USA
| | - Richard A Flavell
- Department of Immunobiology, Yale University School of Medicine, New Haven, 06519, CT, USA
- Howard Hughes Medical Institute, Yale University, New Haven, 06519, CT, USA
| | - Tatyana Svitkina
- Department of Biology, University of Pennsylvania, Philadelphia, 19104, PA, USA
| | - Patrick W Oakes
- Department of Physics, University of Rochester, Rochester, 14627, NY, USA
- Department of Biology, University of Rochester, Rochester, 14627, NY, USA
| | - Mira Krendel
- Cell and Developmental Biology Department, State University of New York Upstate Medical University, Syracuse, 13210, NY, USA.
| | - Nils C Gauthier
- IFOM, FIRC Institute of Molecular Oncology, Milan, 20139, Italy.
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