1
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Zeitzschel N, Lechner SG. The activation thresholds and inactivation kinetics of poking-evoked PIEZO1 and PIEZO2 currents are sensitive to subtle variations in mechanical stimulation parameters. Channels (Austin) 2024; 18:2355123. [PMID: 38754025 DOI: 10.1080/19336950.2024.2355123] [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: 03/27/2024] [Accepted: 05/10/2024] [Indexed: 05/18/2024] Open
Abstract
PIEZO1 and PIEZO2 are mechanically activated ion channels that confer mechanosensitivity to various cell types. PIEZO channels are commonly examined using the so-called poking technique, where currents are recorded in the whole-cell configuration of the patch-clamp technique, while the cell surface is mechanically stimulated with a small fire-polished patch pipette. Currently, there is no gold standard for mechanical stimulation, and therefore, stimulation protocols differ significantly between laboratories with regard to stimulation velocity, angle, and size of the stimulation probe. Here, we systematically examined the impact of variations in these three stimulation parameters on the outcomes of patch-clamp recordings of PIEZO1 and PIEZO2. We show that the inactivation kinetics of PIEZO1 and, to a lesser extent, of PIEZO2 change with the angle at which the probe that is used for mechanical stimulation is positioned and, even more prominently, with the size of its tip. Moreover, we found that the mechanical activation threshold of PIEZO2, but not PIEZO1, decreased with increasing stimulation speeds. Thus, our data show that two key outcome parameters of PIEZO-related patch-clamp studies are significantly affected by common variations in the mechanical stimulation protocols, which calls for caution when comparing data from different laboratories and highlights the need to establish a gold standard for mechanical stimulation to improve comparability and reproducibility of data obtained with the poking technique.
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Affiliation(s)
- Nadja Zeitzschel
- Department of Anesthesiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Stefan G Lechner
- Department of Anesthesiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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2
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Yan Q, Gomis Perez C, Karatekin E. Cell Membrane Tension Gradients, Membrane Flows, and Cellular Processes. Physiology (Bethesda) 2024; 39:0. [PMID: 38501962 DOI: 10.1152/physiol.00007.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 03/18/2024] [Accepted: 03/18/2024] [Indexed: 03/20/2024] Open
Abstract
Cell membrane tension affects and is affected by many fundamental cellular processes, yet it is poorly understood. Recent experiments show that membrane tension can propagate at vastly different speeds in different cell types, reflecting physiological adaptations. Here we briefly review the current knowledge about membrane tension gradients, membrane flows, and their physiological context.
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Affiliation(s)
- Qi Yan
- Cellular and Molecular Physiology, Yale University, New Haven, Connecticut, United States
- Nanobiology Institute, Yale University, West Haven, Connecticut, United States
| | - Carolina Gomis Perez
- Cellular and Molecular Physiology, Yale University, New Haven, Connecticut, United States
- Nanobiology Institute, Yale University, West Haven, Connecticut, United States
| | - Erdem Karatekin
- Cellular and Molecular Physiology, Yale University, New Haven, Connecticut, United States
- Nanobiology Institute, Yale University, West Haven, Connecticut, United States
- Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, United States
- Wu Tsai Institute, Yale University, New Haven, Connecticut, United States
- Saints-Pères Paris Institute for the Neurosciences (SPPIN), Centre National de la Recherche Scientifique (CNRS), Paris, France
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3
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Flaum E, Prakash M. Curved crease origami and topological singularities enable hyperextensibility of L. olor. Science 2024; 384:eadk5511. [PMID: 38843314 DOI: 10.1126/science.adk5511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 04/12/2024] [Indexed: 06/15/2024]
Abstract
Fundamental limits of cellular deformations, such as hyperextension of a living cell, remain poorly understood. Here, we describe how the single-celled protist Lacrymaria olor, a 40-micrometer cell, is capable of reversibly and repeatably extending its necklike protrusion up to 1200 micrometers in 30 seconds. We discovered a layered cortical cytoskeleton and membrane architecture that enables hyperextensions through the folding and unfolding of cellular-scale origami. Physical models of this curved crease origami display topological singularities, including traveling developable cones and cytoskeletal twisted domain walls, which provide geometric control of hyperextension. Our work unravels how cell geometry encodes behavior in single cells and provides inspiration for geometric control in microrobotics and deployable architectures.
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Affiliation(s)
- Eliott Flaum
- Graduate Program in Biophysics, Stanford University, Stanford, CA, USA
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | - Manu Prakash
- Graduate Program in Biophysics, Stanford University, Stanford, CA, USA
- Department of Bioengineering, Stanford University, Stanford, CA, USA
- Department of Biology (courtesy), Stanford University, Stanford, CA, USA
- Department of Oceans (courtesy), Stanford University, Stanford, CA, USA
- Woods Institute for the Environment, Stanford University, Stanford, CA, USA
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4
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Kasuba KC, Buccino AP, Bartram J, Gaub BM, Fauser FJ, Ronchi S, Kumar SS, Geissler S, Nava MM, Hierlemann A, Müller DJ. Mechanical stimulation and electrophysiological monitoring at subcellular resolution reveals differential mechanosensation of neurons within networks. NATURE NANOTECHNOLOGY 2024; 19:825-833. [PMID: 38378885 PMCID: PMC11186759 DOI: 10.1038/s41565-024-01609-1] [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: 04/09/2023] [Accepted: 01/12/2024] [Indexed: 02/22/2024]
Abstract
A growing consensus that the brain is a mechanosensitive organ is driving the need for tools that mechanically stimulate and simultaneously record the electrophysiological response of neurons within neuronal networks. Here we introduce a synchronized combination of atomic force microscopy, high-density microelectrode array and fluorescence microscopy to monitor neuronal networks and to mechanically characterize and stimulate individual neurons at piconewton force sensitivity and nanometre precision while monitoring their electrophysiological activity at subcellular spatial and millisecond temporal resolution. No correlation is found between mechanical stiffness and electrophysiological activity of neuronal compartments. Furthermore, spontaneously active neurons show exceptional functional resilience to static mechanical compression of their soma. However, application of fast transient (∼500 ms) mechanical stimuli to the neuronal soma can evoke action potentials, which depend on the anchoring of neuronal membrane and actin cytoskeleton. Neurons show higher responsivity, including bursts of action potentials, to slower transient mechanical stimuli (∼60 s). Moreover, transient and repetitive application of the same compression modulates the neuronal firing rate. Seemingly, neuronal networks can differentiate and respond to specific characteristics of mechanical stimulation. Ultimately, the developed multiparametric tool opens the door to explore manifold nanomechanobiological responses of neuronal systems and new ways of mechanical control.
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Affiliation(s)
| | | | - Julian Bartram
- Department of Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland
| | - Benjamin M Gaub
- Department of Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland
| | - Felix J Fauser
- Department of Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland
| | | | | | - Sydney Geissler
- Department of Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland
| | - Michele M Nava
- Department of Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland
| | - Andreas Hierlemann
- Department of Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland.
| | - Daniel J Müller
- Department of Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland.
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5
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Lüchtefeld I, Pivkin IV, Gardini L, Zare-Eelanjegh E, Gäbelein C, Ihle SJ, Reichmuth AM, Capitanio M, Martinac B, Zambelli T, Vassalli M. Dissecting cell membrane tension dynamics and its effect on Piezo1-mediated cellular mechanosensitivity using force-controlled nanopipettes. Nat Methods 2024; 21:1063-1073. [PMID: 38802520 PMCID: PMC11166569 DOI: 10.1038/s41592-024-02277-8] [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: 03/21/2022] [Accepted: 04/10/2024] [Indexed: 05/29/2024]
Abstract
The dynamics of cellular membrane tension and its role in mechanosensing, which is the ability of cells to respond to physical stimuli, remain incompletely understood, mainly due to the lack of appropriate tools. Here, we report a force-controlled nanopipette-based method that combines fluidic force microscopy with fluorescence imaging for precise manipulation of the cellular membrane tension while monitoring the impact on single-cell mechanosensitivity. The force-controlled nanopipette enables control of the indentation force imposed on the cell cortex as well as of the aspiration pressure applied to the plasma membrane. We show that this setup can be used to concurrently monitor the activation of Piezo1 mechanosensitive ion channels via calcium imaging. Moreover, the spatiotemporal behavior of the tension propagation is assessed with the fluorescent membrane tension probe Flipper-TR, and further dissected using molecular dynamics modeling. Finally, we demonstrate that aspiration and indentation act independently on the cellular mechanobiological machinery, that indentation induces a local pre-tension in the membrane, and that membrane tension stays confined by links to the cytoskeleton.
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Affiliation(s)
- Ines Lüchtefeld
- Laboratory for Biosensors and Bioelectronics, ETH Zürich, Zurich, Switzerland.
| | - Igor V Pivkin
- Institute of Computing, Università della Svizzera Italiana, Lugano, Switzerland.
- Swiss Institute of Bioinformatics, Lausanne, Switzerland.
| | - Lucia Gardini
- National Institute of Optics, National Research Council, Florence, Italy
- European Laboratory for Non-Linear Spectroscopy, University of Florence, Florence, Italy
| | | | | | - Stephan J Ihle
- Laboratory for Biosensors and Bioelectronics, ETH Zürich, Zurich, Switzerland
| | - Andreas M Reichmuth
- Laboratory for Biosensors and Bioelectronics, ETH Zürich, Zurich, Switzerland
| | - Marco Capitanio
- European Laboratory for Non-Linear Spectroscopy, University of Florence, Florence, Italy
- Physics and Astronomy Department, University of Florence, Florence, Italy
| | - Boris Martinac
- Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia
| | - Tomaso Zambelli
- Laboratory for Biosensors and Bioelectronics, ETH Zürich, Zurich, Switzerland.
| | - Massimo Vassalli
- James Watt School of Engineering, University of Glasgow, Glasgow, UK.
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6
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Zhang Y, Lin C. Lipid osmosis, membrane tension, and other mechanochemical driving forces of lipid flow. Curr Opin Cell Biol 2024; 88:102377. [PMID: 38823338 DOI: 10.1016/j.ceb.2024.102377] [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: 01/10/2024] [Revised: 05/12/2024] [Accepted: 05/13/2024] [Indexed: 06/03/2024]
Abstract
Nonvesicular lipid transport among different membranes or membrane domains plays crucial roles in lipid homeostasis and organelle biogenesis. However, the forces that drive such lipid transport are not well understood. We propose that lipids tend to flow towards the membrane area with a higher membrane protein density in a process termed lipid osmosis. This process lowers the membrane tension in the area, resulting in a membrane tension difference called osmotic membrane tension. We examine the thermodynamic basis and experimental evidence of lipid osmosis and osmotic membrane tension. We predict that lipid osmosis can drive bulk lipid flows between different membrane regions through lipid transfer proteins, scramblases, or similar barriers that selectively pass lipids but not membrane proteins. We also speculate on the biological functions of lipid osmosis. Finally, we explore other driving forces for lipid transfer and describe potential methods and systems to further test our theory.
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Affiliation(s)
- Yongli Zhang
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA.
| | - Chenxiang Lin
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510, USA; Nanobiology Institute, Yale University, West Haven, CT 06516, USA; Department of Biomedical Engineering, Yale University, New Haven, CT 06520, USA.
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7
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Klenow MB, Vigsø MS, Pezeshkian W, Nylandsted J, Lomholt MA, Simonsen AC. Shape of the membrane neck around a hole during plasma membrane repair. Biophys J 2024:S0006-3495(24)00374-6. [PMID: 38824389 DOI: 10.1016/j.bpj.2024.05.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2023] [Revised: 04/05/2024] [Accepted: 05/28/2024] [Indexed: 06/03/2024] Open
Abstract
Plasma membrane damage and rupture occurs frequently in cells, and holes must be sealed rapidly to ensure homeostasis and cell survival. The membrane repair machinery is known to involve recruitment of curvature-inducing annexin proteins, but the connection between membrane remodeling and hole closure is poorly described. The induction of curvature by repair proteins leads to the possible formation of a membrane neck around the hole as a key intermediate structure before sealing. We formulate a theoretical model of equilibrium neck shapes to examine the potential connection to a repair mechanism. Using variational calculus, the shape equations for the membrane near a hole are formulated and solved numerically. The system is described under a condition of fixed area, and a shooting approach is applied to fulfill the boundary conditions at the free membrane edge. A state diagram of neck shapes is produced describing the variation in neck morphology with respect to the membrane area. Two distinct types of necks are predicted, one with conformations curved beyond π existing at positive excess area, whereas flat neck conformations (curved below π) have negative excess area. The results indicate that in cells, the supply of additional membrane area and a change in edge tension is linked to the formation of narrow and curved necks. Such necks may be susceptible to passive or actively induced membrane fission as a possible mechanism for hole sealing during membrane repair in cells.
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Affiliation(s)
- Martin Berg Klenow
- PhyLife - Physical LifeScience, Department of Physics Chemistry and Pharmacy, University of Southern Denmark (SDU), Campusvej 55, Odense M, Denmark
| | - Magnus Staal Vigsø
- PhyLife - Physical LifeScience, Department of Physics Chemistry and Pharmacy, University of Southern Denmark (SDU), Campusvej 55, Odense M, Denmark
| | - Weria Pezeshkian
- Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Jesper Nylandsted
- Danish Cancer Institute (DCI), Copenhagen Ø, Denmark; Department of Molecular Medicine, University of Southern Denmark, Odense C, Denmark
| | - Michael Andersen Lomholt
- PhyLife - Physical LifeScience, Department of Physics Chemistry and Pharmacy, University of Southern Denmark (SDU), Campusvej 55, Odense M, Denmark
| | - Adam Cohen Simonsen
- PhyLife - Physical LifeScience, Department of Physics Chemistry and Pharmacy, University of Southern Denmark (SDU), Campusvej 55, Odense M, Denmark.
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8
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Mukhopadhyay U, Mandal T, Chakraborty M, Sinha B. The Plasma Membrane and Mechanoregulation in Cells. ACS OMEGA 2024; 9:21780-21797. [PMID: 38799362 PMCID: PMC11112598 DOI: 10.1021/acsomega.4c01962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 04/26/2024] [Accepted: 04/30/2024] [Indexed: 05/29/2024]
Abstract
Cells inhabit a mechanical microenvironment that they continuously sense and adapt to. The plasma membrane (PM), serving as the boundary of the cell, plays a pivotal role in this process of adaptation. In this Review, we begin by examining well-studied processes where mechanoregulation proves significant. Specifically, we highlight examples from the immune system and stem cells, besides discussing processes involving fibroblasts and other cell types. Subsequently, we discuss the common molecular players that facilitate the sensing of the mechanical signal and transform it into a chemical response covering integrins YAP/TAZ and Piezo. We then review how this understanding of molecular elements is leveraged in drug discovery and tissue engineering alongside a discussion of the methodologies used to measure mechanical properties. Focusing on the processes of endocytosis, we discuss how cells may respond to altered membrane mechanics using endo- and exocytosis. Through the process of depleting/adding the membrane area, these could also impact membrane mechanics. We compare pathways from studies illustrating the involvement of endocytosis in mechanoregulation, including clathrin-mediated endocytosis (CME) and the CLIC/GEEC (CG) pathway as central examples. Lastly, we review studies on cell-cell fusion during myogenesis, the mechanical integrity of muscle fibers, and the reported and anticipated roles of various molecular players and processes like endocytosis, thereby emphasizing the significance of mechanoregulation at the PM.
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Affiliation(s)
- Upasana Mukhopadhyay
- Department of Biological
Sciences, Indian Institute of Science Education
and Research Kolkata, Mohanpur, West Bengal 741246, India
| | - Tithi Mandal
- Department of Biological
Sciences, Indian Institute of Science Education
and Research Kolkata, Mohanpur, West Bengal 741246, India
| | | | - Bidisha Sinha
- Department of Biological
Sciences, Indian Institute of Science Education
and Research Kolkata, Mohanpur, West Bengal 741246, India
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9
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Fitz GN, Tyska MJ. Molecular counting of myosin force generators in growing filopodia. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.14.593924. [PMID: 38798618 PMCID: PMC11118519 DOI: 10.1101/2024.05.14.593924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Animal cells build actin-based surface protrusions to enable biological activities ranging from cell motility to mechanosensation to solute uptake. Long-standing models of protrusion growth suggest that actin filament polymerization provides the primary mechanical force for "pushing" the plasma membrane outward at the distal tip. Expanding on these actin-centric models, our recent studies used a chemically inducible system to establish that plasma membrane-bound myosin motors, which are abundant in protrusions and accumulate at the distal tips, can also power robust filopodial growth. How protrusion resident myosins coordinate with actin polymerization to drive elongation remains unclear, in part because the number of force generators and thus, the scale of their mechanical contributions remain undefined. To address this gap, we leveraged the SunTag system to count membrane-bound myosin motors in actively growing filopodia. Using this approach, we found that the number of myosins is log-normally distributed with a mean of 12.0 ± 2.5 motors [GeoMean ± GeoSD] per filopodium. Together with unitary force values and duty ratio estimates derived from biophysical studies for the motor used in these experiments, we calculate that a distal tip population of myosins could generate a time averaged force of ∼tens of pN to elongate filopodia. This range is comparable to the expected force production of actin polymerization in this system, a point that necessitates revision of popular physical models for protrusion growth. SIGNIFICANCE STATEMENT This study describes the results of in-cell molecular counting experiments to define the number of myosin motors that are mechanically active in growing filopodia. This data should be used to constrain future physical models of the formation of actin-based protrusions.
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10
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Li M, Xing X, Yuan J, Zeng Z. Research progress on the regulatory role of cell membrane surface tension in cell behavior. Heliyon 2024; 10:e29923. [PMID: 38720730 PMCID: PMC11076917 DOI: 10.1016/j.heliyon.2024.e29923] [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] [Received: 12/05/2023] [Revised: 04/17/2024] [Accepted: 04/17/2024] [Indexed: 05/12/2024] Open
Abstract
Cell membrane surface tension has emerged as a pivotal biophysical factor governing cell behavior and fate. This review systematically delineates recent advances in techniques for cell membrane surface tension quantification, mechanosensing mechanisms, and regulatory roles of cell membrane surface tension in modulating major cellular processes. Micropipette aspiration, tether pulling, and newly developed fluorescent probes enable the measurement of cell membrane surface tension with spatiotemporal precision. Cells perceive cell membrane surface tension via conduits including mechanosensitive ion channels, curvature-sensing proteins (e.g. BAR domain proteins), and cortex-membrane attachment proteins (e.g. ERM proteins). Through membrane receptors like integrins, cells convert mechanical cues into biochemical signals. This conversion triggers cytoskeletal remodeling and extracellular matrix interactions in response to environmental changes. Elevated cell membrane surface tension suppresses cell spreading, migration, and endocytosis while facilitating exocytosis. Moreover, reduced cell membrane surface tension promotes embryonic stem cell differentiation and cancer cell invasion, underscoring cell membrane surface tension as a regulator of cell plasticity. Outstanding questions remain regarding cell membrane surface tension regulatory mechanisms and roles in tissue development/disease in vivo. Emerging tools to manipulate cell membrane surface tension with high spatiotemporal control in combination with omics approaches will facilitate the elucidation of cell membrane surface tension-mediated effects on signaling networks across various cell types/states. This will accelerate the development of cell membrane surface tension-based biomarkers and therapeutics for regenerative medicine and cancer. Overall, this review provides critical insights into cell membrane surface tension as a potent orchestrator of cell function, with broader impacts across mechanobiology.
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Affiliation(s)
- Manqing Li
- School of Public Health, Sun Yat-sen University, Guangzhou, 5180080, China
| | - Xiumei Xing
- School of Public Health, Sun Yat-sen University, Guangzhou, 5180080, China
| | - Jianhui Yuan
- Nanshan District Center for Disease Control and Prevention, Shenzhen, 518054, China
| | - Zhuoying Zeng
- The First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital, Shenzhen University, Shenzhen, 518035, China
- Chemical Analysis & Physical Testing Institute, Shenzhen Center for Disease Control and Prevention, Shenzhen, 518055, China
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11
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Jaganathan A, Toth J, Chen X, Pieuchot L, Shen Y, Reinhart-King C, Shenoy VB. Mechano-metabolism of adherent cells in 2D and 3D microenvironments. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.30.591879. [PMID: 38746096 PMCID: PMC11092625 DOI: 10.1101/2024.04.30.591879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Cells regulate their shape and metabolic activity in response to the mechano-chemical properties of their microenvironment. To elucidate the impact of matrix stiffness and ligand density on a cell's bioenergetics, we developed a non-equilibrium, active chemo-mechanical model that accounts for mechanical energy of the cell and matrix, chemical energy from ATP hydrolysis, interfacial energy, and mechano-sensitive regulation of stress fiber assembly through signaling. By integrating the kinetics and energetics of these processes we introduce the concept of the metabolic potential of the cell that, when minimized, gives experimentally testable predictions of the cell contractility, shape, and the ATP consumption. Specifically, we show that MDA-MB-231 breast cancer cells in 3D collagen gels follow a spherical to spindle to spherical change in morphology with increasing matrix stiffness consistent with experimental observations. This biphasic transition in cell shape emerges from a competition between increased contractility accompanied by ATP hydrolysis enabled by mechano-sensitive signaling, which lowers the volumetric contribution to the metabolic potential of elongated cells and the interfacial energy which is lower for spherical shapes. On 2D hydrogels, our model predicts a hemispherical to spindle to disc shape transition with increasing gel stiffness. In both cases, we show that increasing matrix stiffness monotonically increases the cell's contractility as well as ATP consumption. Our model also predicts how the increased energy demand in stiffer microenvironments is met by AMPK activation, which is confirmed through experimental measurement of activated AMPK levels as a function of matrix stiffness carried out here in both 2D and 3D micro-environments. Further, model predictions of increased AMPK activation on stiffer micro-environments are found to correlate strongly with experimentally measured upregulation of mitochondrial potential, glucose uptake and ATP levels. The insights from our model can be used to understand mechanosensitive regulation of metabolism in physiological events such as metastasis and tumor progression during which cells experience dynamic changes in their microenvironment and metabolic state.
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12
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Di Meo D, Kundu T, Ravindran P, Shah B, Püschel AW. Pip5k1γ regulates axon formation by limiting Rap1 activity. Life Sci Alliance 2024; 7:e202302383. [PMID: 38438249 PMCID: PMC10912816 DOI: 10.26508/lsa.202302383] [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: 09/19/2023] [Revised: 02/26/2024] [Accepted: 02/26/2024] [Indexed: 03/06/2024] Open
Abstract
During their differentiation, neurons establish a highly polarized morphology by forming axons and dendrites. Cortical and hippocampal neurons initially extend several short neurites that all have the potential to become an axon. One of these neurites is then selected as the axon by a combination of positive and negative feedback signals that promote axon formation and prevent the remaining neurites from developing into axons. Here, we show that Pip5k1γ is required for the formation of a single axon as a negative feedback signal that regulates C3G and Rap1 through the generation of phosphatidylinositol-4,5-bisphosphate (PI(4,5)P2). Impairing the function of Pip5k1γ results in a hyper-activation of the Fyn/C3G/Rap1 pathway, which induces the formation of supernumerary axons. Application of a hyper-osmotic shock to modulate membrane tension has a similar effect, increasing Rap1 activity and inducing the formation of supernumerary axons. In both cases, the induction of supernumerary axons can be reverted by expressing constitutively active Pip5k. Our results show that PI(4,5)P2-dependent membrane properties limit the activity of C3G and Rap1 to ensure the extension of a single axon.
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Affiliation(s)
- Danila Di Meo
- https://ror.org/00pd74e08 Institut für Integrative Zellbiologie und Physiologie, Universität Münster, Münster, Germany
- https://ror.org/00pd74e08 Cells-in-Motion Interfaculty Center, University of Münster, Münster, Germany
| | - Trisha Kundu
- https://ror.org/00pd74e08 Institut für Integrative Zellbiologie und Physiologie, Universität Münster, Münster, Germany
- https://ror.org/00pd74e08 Cells-in-Motion Interfaculty Center, University of Münster, Münster, Germany
| | - Priyadarshini Ravindran
- https://ror.org/00pd74e08 Institut für Integrative Zellbiologie und Physiologie, Universität Münster, Münster, Germany
| | - Bhavin Shah
- https://ror.org/00pd74e08 Institut für Integrative Zellbiologie und Physiologie, Universität Münster, Münster, Germany
| | - Andreas W Püschel
- https://ror.org/00pd74e08 Institut für Integrative Zellbiologie und Physiologie, Universität Münster, Münster, Germany
- https://ror.org/00pd74e08 Cells-in-Motion Interfaculty Center, University of Münster, Münster, Germany
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13
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Zhang Y, Lin C. Lipid osmosis, membrane tension, and other mechanochemical driving forces of lipid flow. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.08.574656. [PMID: 38260424 PMCID: PMC10802412 DOI: 10.1101/2024.01.08.574656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Nonvesicular lipid transport among different membranes or membrane domains plays crucial roles in lipid homeostasis and organelle biogenesis. However, the forces that drive such lipid transport are not well understood. We propose that lipids tend to flow towards the membrane area with a higher membrane protein density in a process termed lipid osmosis. This process lowers the membrane tension in the area, resulting in a membrane tension difference called osmotic membrane tension. We examine the thermodynamic basis and experimental evidence of lipid osmosis and osmotic membrane tension. We predict that lipid osmosis can drive bulk lipid flows between different membrane regions through lipid transfer proteins, scramblases, or other similar barriers that selectively pass lipids but not membrane proteins. We also speculate on the biological functions of lipid osmosis. Finally, we explore other driving forces for lipid transfer and describe potential methods and systems to further test our theory.
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Affiliation(s)
- Yongli Zhang
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510, USA
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA
| | - Chenxiang Lin
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510, USA
- Nanobiology Institute, Yale University, West Haven, CT 06516, USA
- Department of Biomedical Engineering, Yale University, New Haven, CT 06520, USA
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14
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Devitt CC, Weng S, Bejar-Padilla VD, Alvarado J, Wallingford JB. PCP and Septins govern the polarized organization of the actin cytoskeleton during convergent extension. Curr Biol 2024; 34:615-622.e4. [PMID: 38199065 PMCID: PMC10887425 DOI: 10.1016/j.cub.2023.12.025] [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: 06/07/2022] [Revised: 09/25/2023] [Accepted: 12/08/2023] [Indexed: 01/12/2024]
Abstract
Convergent extension (CE) requires the coordinated action of the planar cell polarity (PCP) proteins1,2 and the actin cytoskeleton,3,4,5,6 but this relationship remains incompletely understood. For example, PCP signaling orients actomyosin contractions, yet actomyosin is also required for the polarized localization of PCP proteins.7,8 Moreover, the actin-regulating Septins play key roles in actin organization9 and are implicated in PCP and CE in frogs, mice, and fish5,6,10,11,12 but execute only a subset of PCP-dependent cell behaviors. Septin loss recapitulates the severe tissue-level CE defects seen after core PCP disruption yet leaves overt cell polarity intact.5 Together, these results highlight the general fact that cell movement requires coordinated action by distinct but integrated actin populations, such as lamella and lamellipodia in migrating cells13 or medial and junctional actin populations in cells engaged in apical constriction.14,15 In the context of Xenopus mesoderm CE, three such actin populations are important, a superficial meshwork known as the "node-and-cable" system,4,16,17,18 a contractile network at deep cell-cell junctions,6,19 and mediolaterally oriented actin-rich protrusions, which are present both superficially and deeply.4,19,20,21 Here, we exploited the amenability of the uniquely "two-dimensional" node and cable system to probe the relationship between PCP proteins, Septins, and the polarization of this actin network. We find that the PCP proteins Vangl2 and Prickle2 and Septins co-localize at nodes, and that the node and cable system displays a cryptic, PCP- and Septin-dependent anteroposterior (AP) polarity in its organization and dynamics.
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Affiliation(s)
- Caitlin C Devitt
- Department of Molecular Biosciences, University of Texas, Austin, TX 78712, USA
| | - Shinuo Weng
- Department of Molecular Biosciences, University of Texas, Austin, TX 78712, USA
| | | | - José Alvarado
- Department of Physics, University of Texas, Austin, TX 78712, USA
| | - John B Wallingford
- Department of Molecular Biosciences, University of Texas, Austin, TX 78712, USA.
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15
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Ghisleni A, Gauthier NC. Mechanotransduction through membrane tension: It's all about propagation? Curr Opin Cell Biol 2024; 86:102294. [PMID: 38101114 DOI: 10.1016/j.ceb.2023.102294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 11/20/2023] [Accepted: 11/21/2023] [Indexed: 12/17/2023]
Abstract
Over the past 25 years, membrane tension has emerged as a primary mechanical factor influencing cell behavior. Although supporting evidences are accumulating, the integration of this parameter in the lifecycle of cells, organs, and tissues is complex. The plasma membrane is envisioned as a bilayer continuum acting as a 2D fluid. However, it possesses almost infinite combinations of proteins, lipids, and glycans that establish interactions with the extracellular or intracellular environments. This results in a tridimensional composite material with non-trivial dynamics and physics, and the task of integrating membrane mechanics and cellular outcome is a daunting chore for biologists. In light of the most recent discoveries, we aim in this review to provide non-specialist readers some tips on how to solve this conundrum.
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Affiliation(s)
- Andrea Ghisleni
- IFOM ETS, The AIRC Institute of Molecular Oncology, Via Adamello 16, 20139, Milan, Italy
| | - Nils C Gauthier
- IFOM ETS, The AIRC Institute of Molecular Oncology, Via Adamello 16, 20139, Milan, Italy.
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16
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Sabri E, Brosseau C. Electromechanical interactions between cell membrane and nuclear envelope: Beyond the standard Schwan's model of biological cells. Bioelectrochemistry 2024; 155:108583. [PMID: 37883860 DOI: 10.1016/j.bioelechem.2023.108583] [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: 08/28/2023] [Revised: 10/02/2023] [Accepted: 10/02/2023] [Indexed: 10/28/2023]
Abstract
We investigate little-appreciated features of the hierarchical core-shell (CS) models of the electrical, mechanical, and electromechanical interactions between the cell membrane (CM) and nuclear envelope (NE). We first consider a simple model of an individual cell based on a coupled resistor-capacitor (Schwan model (SM)) network and show that the CM, when exposed to ac electric fields, acts as a low pass filter while the NE acts as a wide and asymmetric bandpass filter. We provide a simplified calculation for characteristic time associated with the capacitive charging of the NE and parameterize its range of behavior. We furthermore observe several new features dealing with mechanical analogs of the SM based on elementary spring-damper combinations. The chief merit of these models is that they can predict creep compliance responses of an individual cell under static stress and their effective retardation time constants. Next, we use an alternative and a more accurate CS physical model solved by finite element simulations for which geometrical cell reshaping under electromechanical stress (electrodeformation (ED)) is included in a continuum approach with spatial resolution. We show that under an electric field excitation, the elongated nucleus scales differently compared to the electrodeformed cell.
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Affiliation(s)
- Elias Sabri
- Univ Brest, CNRS, Lab-STICC, CS 93837, 6 avenue Le Gorgeu, 29238 Brest Cedex 3, France
| | - Christian Brosseau
- Univ Brest, CNRS, Lab-STICC, CS 93837, 6 avenue Le Gorgeu, 29238 Brest Cedex 3, France.
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17
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Mandal T, Biswas A, Ghosh T, Manikandan S, Kundu A, Banerjee A, Mitra D, Sinha B. Mechano-regulation by clathrin pit-formation and passive cholesterol-dependent tubules during de-adhesion. Cell Mol Life Sci 2024; 81:43. [PMID: 38217571 PMCID: PMC10787898 DOI: 10.1007/s00018-023-05072-4] [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: 07/08/2023] [Revised: 11/10/2023] [Accepted: 11/30/2023] [Indexed: 01/15/2024]
Abstract
Adherent cells ensure membrane homeostasis during de-adhesion by various mechanisms, including endocytosis. Although mechano-chemical feedbacks involved in this process have been studied, the step-by-step build-up and resolution of the mechanical changes by endocytosis are poorly understood. To investigate this, we studied the de-adhesion of HeLa cells using a combination of interference reflection microscopy, optical trapping and fluorescence experiments. We found that de-adhesion enhanced membrane height fluctuations of the basal membrane in the presence of an intact cortex. A reduction in the tether force was also noted at the apical side. However, membrane fluctuations reveal phases of an initial drop in effective tension followed by saturation. The area fractions of early (Rab5-labelled) and recycling (Rab4-labelled) endosomes, as well as transferrin-labelled pits close to the basal plasma membrane, also transiently increased. On blocking dynamin-dependent scission of endocytic pits, the regulation of fluctuations was not blocked, but knocking down AP2-dependent pit formation stopped the tension recovery. Interestingly, the regulation could not be suppressed by ATP or cholesterol depletion individually but was arrested by depleting both. The data strongly supports Clathrin and AP2-dependent pit-formation to be central to the reduction in fluctuations confirmed by super-resolution microscopy. Furthermore, we propose that cholesterol-dependent pits spontaneously regulate tension under ATP-depleted conditions.
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Affiliation(s)
- Tithi Mandal
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Nadia, Mohanpur, 741246, India
| | - Arikta Biswas
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Nadia, Mohanpur, 741246, India
- Mechanobiology Institute, National University of Singapore, 5A Engineering Drive 1, Singapore, 117411, Singapore
| | - Tanmoy Ghosh
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Nadia, Mohanpur, 741246, India
| | - Sreekanth Manikandan
- NORDITA, KTH Royal Institute of Technology and Stockholm University, Roslagstullsbacken 23, 10691, Stockholm, Sweden
| | - Avijit Kundu
- Department of Physical Sciences, Indian Institute of Science Education and Research Kolkata, Nadia, Mohanpur, 741246, India
- Experimental Physics I, Universität Bayreuth, Universitätsstraße 30, 95447, Bayreuth, Germany
| | - Ayan Banerjee
- Department of Physical Sciences, Indian Institute of Science Education and Research Kolkata, Nadia, Mohanpur, 741246, India
| | - Dhrubaditya Mitra
- NORDITA, KTH Royal Institute of Technology and Stockholm University, Roslagstullsbacken 23, 10691, Stockholm, Sweden
| | - Bidisha Sinha
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Nadia, Mohanpur, 741246, India.
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18
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Mierke CT. Magnetic tweezers in cell mechanics. Methods Enzymol 2024; 694:321-354. [PMID: 38492957 DOI: 10.1016/bs.mie.2023.12.007] [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] [Indexed: 03/18/2024]
Abstract
The chapter provides an overview of the applications of magnetic tweezers in living cells. It discusses the advantages and disadvantages of magnetic tweezers technology with a focus on individual magnetic tweezers configurations, such as electromagnetic tweezers. Solutions to the disadvantages identified are also outlined. The specific role of magnetic tweezers in the field of mechanobiology, such as mechanosensitivity, mechano-allostery and mechanotransduction are also emphasized. The specific usage of magnetic tweezers in mechanically probing cells via specific cell surface receptors, such as mechanosensitive channels is discussed and why mechanical probing has revealed the opening and closing of the channels. Finally, the future direction of magnetic tweezers is presented.
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Affiliation(s)
- Claudia Tanja Mierke
- Faculty of Physics and Earth System Sciences, Peter Debye Institute for Soft Matter Physics, Biological Physics Division, Leipzig University, Leipzig, Germany.
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19
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Honerkamp-Smith AR. Forces and Flows at Cell Surfaces. J Membr Biol 2023; 256:331-340. [PMID: 37773346 PMCID: PMC10947748 DOI: 10.1007/s00232-023-00293-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 09/08/2023] [Indexed: 10/01/2023]
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20
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Dinet C, Torres-Sánchez A, Lanfranco R, Di Michele L, Arroyo M, Staykova M. Patterning and dynamics of membrane adhesion under hydraulic stress. Nat Commun 2023; 14:7445. [PMID: 37978292 PMCID: PMC10656516 DOI: 10.1038/s41467-023-43246-7] [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: 04/30/2023] [Accepted: 11/02/2023] [Indexed: 11/19/2023] Open
Abstract
Hydraulic fracturing plays a major role in cavity formation during embryonic development, when pressurized fluid opens microlumens at cell-cell contacts, which evolve to form a single large lumen. However, the fundamental physical mechanisms behind these processes remain masked by the complexity and specificity of biological systems. Here, we show that adhered lipid vesicles subjected to osmotic stress form hydraulic microlumens similar to those in cells. Combining vesicle experiments with theoretical modelling and numerical simulations, we provide a physical framework for the hydraulic reconfiguration of cell-cell adhesions. We map the conditions for microlumen formation from a pristine adhesion, the emerging dynamical patterns and their subsequent maturation. We demonstrate control of the fracturing process depending on the applied pressure gradients and the type and density of membrane bonds. Our experiments further reveal an unexpected, passive transition of microlumens to closed buds that suggests a physical route to adhesion remodeling by endocytosis.
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Affiliation(s)
- Céline Dinet
- Department of Physics, Durham University, Durham, UK
- Laboratoire de Chimie Bactérienne, Institut de Microbiologie de la Méditerranée, CNRS-Aix-Marseille University, 31 Chemin Joseph Aiguier, 13009, Marseille, France
| | - Alejandro Torres-Sánchez
- Universitat Politècnica de Catalunya-BarcelonaTech, 08034, Barcelona, Spain
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, 08028, Barcelona, Spain
- European Molecular Biology Laboratory (EMBL-Barcelona), 08003, Barcelona, Spain
| | - Roberta Lanfranco
- Department of Physics, Cavendish Laboratory, University of Cambridge, Cambridge, UK
| | - Lorenzo Di Michele
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK
- Department of Chemistry, Imperial College of London, London, UK
| | - Marino Arroyo
- Universitat Politècnica de Catalunya-BarcelonaTech, 08034, Barcelona, Spain.
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, 08028, Barcelona, Spain.
- Centre Internacional de Mètodes Numèrics en Enginyeria (CIMNE), 08034, Barcelona, Spain.
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21
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Weng S, Devitt CC, Nyaoga BM, Havnen AE, Alvarado J, Wallingford JB. New tools reveal PCP-dependent polarized mechanics in the cortex and cytoplasm of single cells during convergent extension. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.07.566066. [PMID: 37986924 PMCID: PMC10659385 DOI: 10.1101/2023.11.07.566066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
Understanding biomechanics of biological systems is crucial for unraveling complex processes like tissue morphogenesis. However, current methods for studying cellular mechanics in vivo are limited by the need for specialized equipment and often provide limited spatiotemporal resolution. Here we introduce two new techniques, Tension by Transverse Fluctuation (TFlux) and in vivo microrheology, that overcome these limitations. They both offer time-resolved, subcellular biomechanical analysis using only fluorescent reporters and widely available microscopes. Employing these two techniques, we have revealed a planar cell polarity (PCP)-dependent mechanical gradient both in the cell cortex and the cytoplasm of individual cells engaged in convergent extension. Importantly, the non-invasive nature of these methods holds great promise for its application for uncovering subcellular mechanical variations across a wide array of biological contexts. Summary Non-invasive imaging-based techniques providing time-resolved biomechanical analysis at subcellular scales in developing vertebrate embryos.
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22
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Melo S, Guerrero P, Moreira Soares M, Bordin JR, Carneiro F, Carneiro P, Dias MB, Carvalho J, Figueiredo J, Seruca R, Travasso RDM. The ECM and tissue architecture are major determinants of early invasion mediated by E-cadherin dysfunction. Commun Biol 2023; 6:1132. [PMID: 37938268 PMCID: PMC10632478 DOI: 10.1038/s42003-023-05482-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: 01/20/2023] [Accepted: 10/18/2023] [Indexed: 11/09/2023] Open
Abstract
Germline mutations of E-cadherin cause Hereditary Diffuse Gastric Cancer (HDGC), a highly invasive cancer syndrome characterised by the occurrence of diffuse-type gastric carcinoma and lobular breast cancer. In this disease, E-cadherin-defective cells are detected invading the adjacent stroma since very early stages. Although E-cadherin loss is well established as a triggering event, other determinants of the invasive process persist largely unknown. Herein, we develop an experimental strategy that comprises in vitro extrusion assays using E-cadherin mutants associated to HDGC, as well as mathematical models epitomising epithelial dynamics and its interaction with the extracellular matrix (ECM). In vitro, we verify that E-cadherin dysfunctional cells detach from the epithelial monolayer and extrude basally into the ECM. Through phase-field modelling we demonstrate that, aside from loss of cell-cell adhesion, increased ECM attachment further raises basal extrusion efficiency. Importantly, by combining phase-field and vertex model simulations, we show that the cylindrical structure of gastric glands strongly promotes the cell's invasive ability. Moreover, we validate our findings using a dissipative particle dynamics simulation of epithelial extrusion. Overall, we provide the first evidence that cancer cell invasion is the outcome of defective cell-cell linkages, abnormal interplay with the ECM, and a favourable 3D tissue structure.
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Affiliation(s)
- Soraia Melo
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- Ipatimup - Institute of Molecular Pathology and Immunology of the University of Porto, University of Porto, Porto, Portugal
| | - Pilar Guerrero
- Departamento de Matemáticas and Grupo Interdisciplinar de Sistemas Complejos (GISC), Universidad Carlos III de Madrid, Leganés, Spain
| | - Maurício Moreira Soares
- Oslo Center for Biostatistics and Epidemiology, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - José Rafael Bordin
- Department of Physics, Institute of Physics and Mathematics, Federal University of Pelotas, Capão do Leão, Rio Grande do Sul, Brazil
| | - Fátima Carneiro
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- Ipatimup - Institute of Molecular Pathology and Immunology of the University of Porto, University of Porto, Porto, Portugal
- Department of Pathology, Faculty of Medicine, University of Porto, Porto, Portugal
| | - Patrícia Carneiro
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- Ipatimup - Institute of Molecular Pathology and Immunology of the University of Porto, University of Porto, Porto, Portugal
| | - Maria Beatriz Dias
- CISUC, Department of Informatics Engineering, University of Coimbra, Coimbra, Portugal
| | - João Carvalho
- CFisUC, Department of Physics, University of Coimbra, Coimbra, Portugal
| | - Joana Figueiredo
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.
- Ipatimup - Institute of Molecular Pathology and Immunology of the University of Porto, University of Porto, Porto, Portugal.
- Department of Pathology, Faculty of Medicine, University of Porto, Porto, Portugal.
| | - Raquel Seruca
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- Ipatimup - Institute of Molecular Pathology and Immunology of the University of Porto, University of Porto, Porto, Portugal
- Department of Pathology, Faculty of Medicine, University of Porto, Porto, Portugal
| | - Rui D M Travasso
- CFisUC, Department of Physics, University of Coimbra, Coimbra, Portugal.
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23
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Efremov YM, Shimolina L, Gulin A, Ignatova N, Gubina M, Kuimova MK, Timashev PS, Shirmanova MV. Correlation of Plasma Membrane Microviscosity and Cell Stiffness Revealed via Fluorescence-Lifetime Imaging and Atomic Force Microscopy. Cells 2023; 12:2583. [PMID: 37947661 PMCID: PMC10650173 DOI: 10.3390/cells12212583] [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: 09/17/2023] [Revised: 10/23/2023] [Accepted: 10/31/2023] [Indexed: 11/12/2023] Open
Abstract
The biophysical properties of cells described at the level of whole cells or their membranes have many consequences for their biological behavior. However, our understanding of the relationships between mechanical parameters at the level of cell (stiffness, viscoelasticity) and at the level of the plasma membrane (fluidity) remains quite limited, especially in the context of pathologies, such as cancer. Here, we investigated the correlations between cells' stiffness and viscoelastic parameters, mainly determined via the actin cortex, and plasma membrane microviscosity, mainly determined via its lipid profile, in cancer cells, as these are the keys to their migratory capacity. The mechanical properties of cells were assessed using atomic force microscopy (AFM). The microviscosity of membranes was visualized using fluorescence-lifetime imaging microscopy (FLIM) with the viscosity-sensitive probe BODIPY 2. Measurements were performed for five human colorectal cancer cell lines that have different migratory activity (HT29, Caco-2, HCT116, SW 837, and SW 480) and their chemoresistant counterparts. The actin cytoskeleton and the membrane lipid composition were also analyzed to verify the results. The cell stiffness (Young's modulus), measured via AFM, correlated well (Pearson r = 0.93) with membrane microviscosity, measured via FLIM, and both metrics were elevated in more motile cells. The associations between stiffness and microviscosity were preserved upon acquisition of chemoresistance to one of two chemotherapeutic drugs. These data clearly indicate that mechanical parameters, determined by two different cellular structures, are interconnected in cells and play a role in their intrinsic migratory potential.
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Affiliation(s)
- Yuri M. Efremov
- Institute for Regenerative Medicine, Sechenov First Moscow State Medical University (Sechenov University), 119991 Moscow, Russia;
| | - Liubov Shimolina
- Institute of Experimental Oncology and Biomedical Technologies, Privolzhsky Research Medical University, 603005 Nizhny Novgorod, Russia; (L.S.); (N.I.); (M.V.S.)
| | - Alexander Gulin
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russia; (A.G.); (M.G.)
| | - Nadezhda Ignatova
- Institute of Experimental Oncology and Biomedical Technologies, Privolzhsky Research Medical University, 603005 Nizhny Novgorod, Russia; (L.S.); (N.I.); (M.V.S.)
| | - Margarita Gubina
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russia; (A.G.); (M.G.)
| | - Marina K. Kuimova
- Department of Chemistry, Imperial College London, White City Campus, London W12 0BZ, UK;
| | - Peter S. Timashev
- Institute for Regenerative Medicine, Sechenov First Moscow State Medical University (Sechenov University), 119991 Moscow, Russia;
- World-Class Research Center “Digital Biodesign and Personalized Healthcare”, Sechenov University, 119991 Moscow, Russia
| | - Marina V. Shirmanova
- Institute of Experimental Oncology and Biomedical Technologies, Privolzhsky Research Medical University, 603005 Nizhny Novgorod, Russia; (L.S.); (N.I.); (M.V.S.)
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24
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Riedl M, Sixt M. The excitable nature of polymerizing actin and the Belousov-Zhabotinsky reaction. Front Cell Dev Biol 2023; 11:1287420. [PMID: 38020899 PMCID: PMC10643615 DOI: 10.3389/fcell.2023.1287420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 10/16/2023] [Indexed: 12/01/2023] Open
Abstract
The intricate regulatory processes behind actin polymerization play a crucial role in cellular biology, including essential mechanisms such as cell migration or cell division. However, the self-organizing principles governing actin polymerization are still poorly understood. In this perspective article, we compare the Belousov-Zhabotinsky (BZ) reaction, a classic and well understood chemical oscillator known for its self-organizing spatiotemporal dynamics, with the excitable dynamics of polymerizing actin. While the BZ reaction originates from the domain of inorganic chemistry, it shares remarkable similarities with actin polymerization, including the characteristic propagating waves, which are influenced by geometry and external fields, and the emergent collective behavior. Starting with a general description of emerging patterns, we elaborate on single droplets or cell-level dynamics, the influence of geometric confinements and conclude with collective interactions. Comparing these two systems sheds light on the universal nature of self-organization principles in both living and inanimate systems.
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Affiliation(s)
- Michael Riedl
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
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25
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Su R, Wang S, McDargh Z, O'Shaughnessy B. Three membrane fusion pore families determine the pathway to pore dilation. Biophys J 2023; 122:3986-3998. [PMID: 37644721 PMCID: PMC10560699 DOI: 10.1016/j.bpj.2023.08.021] [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: 12/20/2022] [Revised: 06/19/2023] [Accepted: 08/25/2023] [Indexed: 08/31/2023] Open
Abstract
During exocytosis secretory vesicles fuse with a target membrane and release neurotransmitters, hormones, or other bioactive molecules through a membrane fusion pore. The initially small pore may subsequently dilate for full contents release, as commonly observed in amperometric traces. The size, shape, and evolution of the pore is critical to the course of contents release, but exact fusion pore solutions accounting for membrane tension and bending energy constraints have not been available. Here, we obtained exact solutions for fusion pores between two membranes. We find three families: a narrow pore, a wide pore, and an intermediate tether-like pore. For high tensions these are close to the catenoidal and tether solutions recently reported for freely hinged membrane boundaries. We suggest membrane fusion initially generates a stable narrow pore, and the dilation pathway is a transition to the stable wide pore family. The unstable intermediate pore is the transition state that sets the energy barrier for this dilation pathway. Pore dilation is mechanosensitive, as the energy barrier is lowered by increased membrane tension. Finally, we study fusion pores in nanodiscs, powerful systems for the study of individual pores. We show that nanodiscs stabilize fusion pores by locking them into the narrow pore family.
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Affiliation(s)
- Rui Su
- Department of Chemical Engineering, Columbia University, New York City, New York
| | - Shuyuan Wang
- Department of Chemical Engineering, Columbia University, New York City, New York; Department of Physics, Columbia University, New York City, New York
| | - Zachary McDargh
- Department of Chemical Engineering, Columbia University, New York City, New York
| | - Ben O'Shaughnessy
- Department of Chemical Engineering, Columbia University, New York City, New York.
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26
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Xu D, Yang Y, Emmerich L, Wang Y, Zhang K. Divergent Deborah number-dependent transition from homogeneity to heterogeneity. Nat Commun 2023; 14:6003. [PMID: 37752163 PMCID: PMC10522598 DOI: 10.1038/s41467-023-41738-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 09/18/2023] [Indexed: 09/28/2023] Open
Abstract
Heterogeneous structures are ubiquitous in natural organisms. Native heterogeneous structures inspire many artificial structures that are playing important roles in modern society, while it is challenging to identify the relevant factors in forming these structures due to the complexity of living systems. Here, hybrid hydrogels consisting of flexible polymer networks with embedded stiff cellulose nanocrystals (CNCs) are considered an open system to simulate the generalized formation of heterogeneous core-sheath structures. As the result of the modified air drying process of hybrid hydrogels, the formation of heterogeneous core-sheath structure is found to be correlated to the relative evaporation speed. Specifically, the formation of such heterogeneity in xerogel fibers is found to be correlated with the divergence of Deborah number (De). During the transition of De from large to small values with accompanying morphologies, the turning point is around De = 1. The mechanism can be considered a relative humidity-dependent glass transition behavior. These unique heterogeneous structures play a key role in tuning water permeation and water sorption capacity. Insights into these aspects can prospectively contribute to a better understanding of the native heterogeneous structures for bionics design.
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Affiliation(s)
- Dan Xu
- Sustainable Materials and Chemistry, Department of Wood Technology and Wood-based Composites, University of Göttingen, Büsgenweg 4, D-37077, Göttingen, Germany
| | - Yang Yang
- Sustainable Materials and Chemistry, Department of Wood Technology and Wood-based Composites, University of Göttingen, Büsgenweg 4, D-37077, Göttingen, Germany
| | - Lukas Emmerich
- Department of Wood Biology and Wood Products, University of Göttingen, Büsgenweg 4, D-37077, Göttingen, Germany
| | - Yong Wang
- Laboratory for Fluid Physics, Pattern Formation and Biocomplexity, Max Planck Institute for Dynamics and Self-Organization, Am Faßberg 17, D-37077, Göttingen, Germany
| | - Kai Zhang
- Sustainable Materials and Chemistry, Department of Wood Technology and Wood-based Composites, University of Göttingen, Büsgenweg 4, D-37077, Göttingen, Germany.
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Quiroga X, Walani N, Disanza A, Chavero A, Mittens A, Tebar F, Trepat X, Parton RG, Geli MI, Scita G, Arroyo M, Le Roux AL, Roca-Cusachs P. A mechanosensing mechanism controls plasma membrane shape homeostasis at the nanoscale. eLife 2023; 12:e72316. [PMID: 37747150 PMCID: PMC10569792 DOI: 10.7554/elife.72316] [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: 07/19/2021] [Accepted: 09/24/2023] [Indexed: 09/26/2023] Open
Abstract
As cells migrate and experience forces from their surroundings, they constantly undergo mechanical deformations which reshape their plasma membrane (PM). To maintain homeostasis, cells need to detect and restore such changes, not only in terms of overall PM area and tension as previously described, but also in terms of local, nanoscale topography. Here, we describe a novel phenomenon, by which cells sense and restore mechanically induced PM nanoscale deformations. We show that cell stretch and subsequent compression reshape the PM in a way that generates local membrane evaginations in the 100 nm scale. These evaginations are recognized by I-BAR proteins, which triggers a burst of actin polymerization mediated by Rac1 and Arp2/3. The actin polymerization burst subsequently re-flattens the evagination, completing the mechanochemical feedback loop. Our results demonstrate a new mechanosensing mechanism for PM shape homeostasis, with potential applicability in different physiological scenarios.
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Affiliation(s)
- Xarxa Quiroga
- Institute for Bioengineering of Catalonia, the Barcelona Institute of Technology (BIST)BarcelonaSpain
- Departament de Biomedicina, Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de BarcelonaBarcelonaSpain
| | - Nikhil Walani
- Department of Applied Mechanics, IIT DelhiNew DelhiIndia
| | - Andrea Disanza
- IFOM ETS - The AIRC Institute of Molecular OncologyMilanItaly
| | - Albert Chavero
- Departament de Biomedicina, Unitat de Biologia Cel·lular, Facultat de Medicina i Ciències de la Salut, Centre de Recerca Biomèdica CELLEX, Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Universitat de BarcelonaBarcelonaSpain
| | - Alexandra Mittens
- Institute for Bioengineering of Catalonia, the Barcelona Institute of Technology (BIST)BarcelonaSpain
| | - Francesc Tebar
- Departament de Biomedicina, Unitat de Biologia Cel·lular, Facultat de Medicina i Ciències de la Salut, Centre de Recerca Biomèdica CELLEX, Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Universitat de BarcelonaBarcelonaSpain
| | - Xavier Trepat
- Institute for Bioengineering of Catalonia, the Barcelona Institute of Technology (BIST)BarcelonaSpain
| | - Robert G Parton
- Institute for Molecular Bioscience and Centre for Microscopy and Microanalysis, University of QueenslandBrisbaneAustralia
| | | | - Giorgio Scita
- IFOM ETS - The AIRC Institute of Molecular OncologyMilanItaly
- Department of Oncology and Haemato-Oncology, University of MilanMilanItaly
| | - Marino Arroyo
- Institute for Bioengineering of Catalonia, the Barcelona Institute of Technology (BIST)BarcelonaSpain
- Universitat Politècnica de Catalunya (UPC), Campus Nord, Carrer de Jordi GironaBarcelonaSpain
- Centre Internacional de Mètodes Numèrics en Enginyeria (CIMNE)BarcelonaSpain
| | - Anabel-Lise Le Roux
- Institute for Bioengineering of Catalonia, the Barcelona Institute of Technology (BIST)BarcelonaSpain
| | - Pere Roca-Cusachs
- Institute for Bioengineering of Catalonia, the Barcelona Institute of Technology (BIST)BarcelonaSpain
- Departament de Biomedicina, Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de BarcelonaBarcelonaSpain
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28
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Flaum E, Prakash M. Curved crease origami and topological singularities at a cellular scale enable hyper-extensibility of Lacrymaria olor. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.04.551915. [PMID: 37577489 PMCID: PMC10418517 DOI: 10.1101/2023.08.04.551915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
Eukaryotic cells undergo dramatic morphological changes during cell division, phagocytosis and motility. Fundamental limits of cellular morphodynamics such as how fast or how much cellular shapes can change without harm to a living cell remain poorly understood. Here we describe hyper-extensibility in the single-celled protist Lacrymaria olor, a 40 μm cell which is capable of reversible and repeatable extensions (neck-like protrusions) up to 1500 μm in 30 seconds. We discover that a unique and intricate organization of cortical cytoskeleton and membrane enables these hyper-extensions that can be described as the first cellular scale curved crease origami. Furthermore, we show how these topological singularities including d-cones and twisted domain walls provide a geometrical control mechanism for the deployment of membrane and microtubule sheets as they repeatably spool thousands of time from the cell body. We lastly build physical origami models to understand how these topological singularities provide a mechanism for the cell to control the hyper-extensile deployable structure. This new geometrical motif where a cell employs curved crease origami to perform a physiological function has wide ranging implications in understanding cellular morphodynamics and direct applications in deployable micro-robotics.
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Affiliation(s)
- Eliott Flaum
- Graduate Program in Biophysics
- Department of Bioengineering
- Stanford University
| | - Manu Prakash
- Graduate Program in Biophysics
- Department of Bioengineering
- Department of Biology (courtesy)
- Department of Oceans (courtesy)
- Stanford University
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29
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Rutkowski DM, Vincenzetti V, Vavylonis D, Martin SG. Cdc42 mobility and membrane flows regulate fission yeast cell shape and survival. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.21.550042. [PMID: 37503115 PMCID: PMC10370159 DOI: 10.1101/2023.07.21.550042] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Local Cdc42 GTPase activation promotes polarized exocytosis, resulting in membrane flows that deplete low-mobility membrane-associated proteins from the growth region. To investigate the self-organizing properties of the Cdc42 secretion-polarization system under membrane flow, we developed a reaction-diffusion particle model. The model includes positive feedback activation of Cdc42, hydrolysis by GTPase-activating proteins (GAPs), and flow-induced displacement by exo/endocytosis. Simulations show how polarization relies on flow-induced depletion of low mobility GAPs. To probe the role of Cdc42 mobility in the fission yeast Schizosaccharomyces pombe, we changed its membrane binding properties by replacing its prenylation site with 1, 2 or 3 repeats of the Rit1 C terminal membrane binding domain (ritC), yielding alleles with progressively lower unbinding and diffusion rates. Concordant modelling predictions and experimental observations show that lower Cdc42 mobility results in lower Cdc42 activation level and wider patches. Indeed, while Cdc42-1ritC cells are viable and polarized, Cdc42-2ritC polarize poorly and Cdc42-3ritC is inviable. The model further predicts that GAP depletion increases Cdc42 activity at the expense of loss of polarization. Experiments confirm this prediction, as deletion of Cdc42 GAPs restores viability to Cdc42-3ritC cells. Our combined experimental and modelling studies demonstrate how membrane flows are an integral part of Cdc42-driven pattern formation.
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Affiliation(s)
| | | | | | - Sophie G. Martin
- Department of Fundamental Microbiology, University of Lausanne, Switzerland
- Department of Molecular and Cellular Biology, University of Geneva, Quai Ernest-Ansermet 30, 1205 Geneva
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30
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Yuan W, Zhang X, Fan X. The Role of the Piezo1 Mechanosensitive Channel in Heart Failure. Curr Issues Mol Biol 2023; 45:5830-5848. [PMID: 37504285 PMCID: PMC10378680 DOI: 10.3390/cimb45070369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 07/02/2023] [Accepted: 07/08/2023] [Indexed: 07/29/2023] Open
Abstract
Mechanotransduction (MT) is inseparable from the pathobiology of heart failure (HF). However, the effects of mechanical forces on HF remain unclear. This review briefly describes how Piezo1 functions in HF-affected cells, including endothelial cells (ECs), cardiac fibroblasts (CFs), cardiomyocytes (CMs), and immune cells. Piezo1 is a mechanosensitive ion channel that has been extensively studied in recent years. Piezo1 responds to different mechanical forces and converts them into intracellular signals. The pathways that modulate the Piezo1 switch have also been briefly described. Experimental drugs that specifically activate Piezo1-like proteins, such as Yoda1, Jedi1, and Jedi2, are available for clinical studies to treat Piezo1-related diseases. The only mechanosensitive ion-channel-specific inhibitor available is GsMTx4, which can turn off Piezo1 by modulating the local membrane tension. Ultrasound waves can modulate Piezo1 switching in vitro with the assistance of microbubbles. This review provides new possible targets for heart failure therapy by exploring the cellular functions of Piezo1 that are involved in the progression of the disease. Modulation of Piezo1 activity may, therefore, effectively delay the progression of heart failure.
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Affiliation(s)
- Weihua Yuan
- National Clinical Research Center for Child Health, Children's Hospital, Zhejiang University School of Medicine, 3333 Binsheng Rd, Hangzhou 310052, China
| | - Xicheng Zhang
- National Clinical Research Center for Child Health, Department of Cardiac Surgery, Children's Hospital, Zhejiang University School of Medicine, 3333 Binsheng Rd, Hangzhou 310052, China
| | - Xiangming Fan
- National Clinical Research Center for Child Health, Department of Cardiac Surgery, Children's Hospital, Zhejiang University School of Medicine, 3333 Binsheng Rd, Hangzhou 310052, China
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31
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Keren K. Effective membrane tension: A long-range integrator of cellular dynamics. Cell 2023; 186:2956-2958. [PMID: 37419084 DOI: 10.1016/j.cell.2023.05.033] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 05/22/2023] [Accepted: 05/22/2023] [Indexed: 07/09/2023]
Abstract
Membrane tension has been proposed to mechanically couple processes along the cell's boundary. In this issue of Cell, De Belly et al. show that local protrusion or contraction elicit a global membrane tension increase within seconds, whereas tension perturbations that engage only the membrane remain localized.
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Affiliation(s)
- Kinneret Keren
- Department of Physics, Network Biology Research Laboratories and Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 32000, Israel.
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32
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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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33
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Wang X, Li N, Zhang Z, Qin K, Zhang H, Shao S, Liu B. Visualization of Cell Membrane Tension Regulated by the Microfilaments as a "Shock Absorber" in Micropatterned Cells. BIOLOGY 2023; 12:889. [PMID: 37372173 DOI: 10.3390/biology12060889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 06/17/2023] [Indexed: 06/29/2023]
Abstract
The extracellular stress signal transmits along the cell membrane-cytoskeleton-focal adhesions (FAs) complex, regulating the cell function through membrane tension. However, the mechanism of the complex regulating membrane tension is still unclear. This study designed polydimethylsiloxane stamps with specific shapes to change the actin filaments' arrangement and FAs' distribution artificially in live cells, visualized the membrane tension in real time, and introduced the concept of information entropy to describe the order degree of the actin filaments and plasma membrane tension. The results showed that the actin filaments' arrangement and FAs' distribution in the patterned cells were changed significantly. The hypertonic solution resulted in the plasma membrane tension of the pattern cell changing more evenly and slowly in the zone rich in cytoskeletal filaments than in the zone lacking filaments. In addition, the membrane tension changed less in the adhesive area than in the non-adhesive area when destroying the cytoskeletal microfilaments. This suggested that patterned cells accumulated more actin filaments in the zone where FAs were difficult to generate to maintain the stability of the overall membrane tension. The actin filaments act as shock absorbers to cushion the alternation in membrane tension without changing the final value of membrane tension.
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Affiliation(s)
- Xianmeng Wang
- School of Biomedical Engineering, Faculty of Medicine, Dalian University of Technology, Dalian 116024, China
| | - Na Li
- School of Biomedical Engineering, Faculty of Medicine, Dalian University of Technology, Dalian 116024, China
- Liaoning Key Laboratory of Integrated Circuit and Biomedical Electronic System, Dalian University of Technology, Dalian 116024, China
| | - Zhengyao Zhang
- School of Life and Pharmaceutical Sciences, Dalian University of Technology, Panjin 124221, China
| | - Kairong Qin
- School of Biomedical Engineering, Faculty of Medicine, Dalian University of Technology, Dalian 116024, China
| | - Hangyu Zhang
- School of Biomedical Engineering, Faculty of Medicine, Dalian University of Technology, Dalian 116024, China
- Liaoning Key Laboratory of Integrated Circuit and Biomedical Electronic System, Dalian University of Technology, Dalian 116024, China
| | - Shuai Shao
- School of Biomedical Engineering, Faculty of Medicine, Dalian University of Technology, Dalian 116024, China
- Liaoning Key Laboratory of Integrated Circuit and Biomedical Electronic System, Dalian University of Technology, Dalian 116024, China
| | - Bo Liu
- School of Biomedical Engineering, Faculty of Medicine, Dalian University of Technology, Dalian 116024, China
- Liaoning Key Laboratory of Integrated Circuit and Biomedical Electronic System, Dalian University of Technology, Dalian 116024, China
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34
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Mahapatra A, Rangamani P. Formation of protein-mediated bilayer tubes is governed by a snapthrough transition. SOFT MATTER 2023; 19:4345-4359. [PMID: 37255421 PMCID: PMC10330560 DOI: 10.1039/d2sm01676a] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Plasma membrane tubes are ubiquitous in cellular membranes and in the membranes of intracellular organelles. They play crucial roles in trafficking, ion transport, and cellular motility. These tubes can be formed due to localized forces acting on the membrane or by the curvature induced by membrane-bound proteins. Here, we present a mathematical framework to model cylindrical tubular protrusions formed by proteins that induce anisotropic spontaneous curvature. Our analysis revealed that the tube radius depends on an effective tension that includes contributions from the bare membrane tension and the protein-induced curvature. We also found that the length of the tube undergoes an abrupt transition from a short, dome-shaped membrane to a long cylinder and this transition is characteristic of a snapthrough instability. Finally, we show that the snapthrough instability depends on the different parameters including coat area, bending modulus, and extent of protein-induced curvature. Our findings have implications for tube formation due to BAR-domain proteins in processes such as endocytosis, t-tubule formation in myocytes, and cristae formation in mitochondria.
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Affiliation(s)
- Arijit Mahapatra
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, CA 92093, USA.
| | - Padmini Rangamani
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, CA 92093, USA.
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35
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Ogunmowo TH, Jing H, Raychaudhuri S, Kusick GF, Imoto Y, Li S, Itoh K, Ma Y, Jafri H, Dalva MB, Chapman ER, Ha T, Watanabe S, Liu J. Membrane compression by synaptic vesicle exocytosis triggers ultrafast endocytosis. Nat Commun 2023; 14:2888. [PMID: 37210439 PMCID: PMC10199930 DOI: 10.1038/s41467-023-38595-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Accepted: 05/09/2023] [Indexed: 05/22/2023] Open
Abstract
Compensatory endocytosis keeps the membrane surface area of secretory cells constant following exocytosis. At chemical synapses, clathrin-independent ultrafast endocytosis maintains such homeostasis. This endocytic pathway is temporally and spatially coupled to exocytosis; it initiates within 50 ms at the region immediately next to the active zone where vesicles fuse. However, the coupling mechanism is unknown. Here, we demonstrate that filamentous actin is organized as a ring, surrounding the active zone at mouse hippocampal synapses. Assuming the membrane area conservation is due to this actin ring, our theoretical model suggests that flattening of fused vesicles exerts lateral compression in the plasma membrane, resulting in rapid formation of endocytic pits at the border between the active zone and the surrounding actin-enriched region. Consistent with model predictions, our data show that ultrafast endocytosis requires sufficient compression by exocytosis of multiple vesicles and does not initiate when actin organization is disrupted, either pharmacologically or by ablation of the actin-binding protein Epsin1. Our work suggests that membrane mechanics underlie the rapid coupling of exocytosis to endocytosis at synapses.
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Affiliation(s)
- Tyler H Ogunmowo
- Department of Cell Biology, School of Medicine, Johns Hopkins University, Baltimore, MD, US
- Center for Cell Dynamics, School of Medicine, Johns Hopkins University, Baltimore, MD, US
- Biochemistry, Cellular and Molecular Biology graduate program, Johns Hopkins University, Baltimore, MD, US
| | - Haoyuan Jing
- Department of Cell Biology, School of Medicine, Johns Hopkins University, Baltimore, MD, US
- Center for Cell Dynamics, School of Medicine, Johns Hopkins University, Baltimore, MD, US
| | - Sumana Raychaudhuri
- Department of Cell Biology, School of Medicine, Johns Hopkins University, Baltimore, MD, US
- Center for Cell Dynamics, School of Medicine, Johns Hopkins University, Baltimore, MD, US
| | - Grant F Kusick
- Department of Cell Biology, School of Medicine, Johns Hopkins University, Baltimore, MD, US
- Center for Cell Dynamics, School of Medicine, Johns Hopkins University, Baltimore, MD, US
- Biochemistry, Cellular and Molecular Biology graduate program, Johns Hopkins University, Baltimore, MD, US
| | - Yuuta Imoto
- Department of Cell Biology, School of Medicine, Johns Hopkins University, Baltimore, MD, US
- Center for Cell Dynamics, School of Medicine, Johns Hopkins University, Baltimore, MD, US
| | - Shuo Li
- Department of Cell Biology, School of Medicine, Johns Hopkins University, Baltimore, MD, US
- Center for Cell Dynamics, School of Medicine, Johns Hopkins University, Baltimore, MD, US
- Department of Ophthalmology, School of Medicine, Stanford University, Palo Alto, CA, US
| | - Kie Itoh
- Department of Cell Biology, School of Medicine, Johns Hopkins University, Baltimore, MD, US
- Center for Cell Dynamics, School of Medicine, Johns Hopkins University, Baltimore, MD, US
| | - Ye Ma
- Department of Biomedical Engineering, School of Medicine, Johns Hopkins University, Baltimore, MD, US
| | - Haani Jafri
- Department of Neuroscience and Jefferson Synaptic Biology Center, Thomas Jefferson University, Philadelphia, PA, US
| | - Matthew B Dalva
- Department of Neuroscience and Jefferson Synaptic Biology Center, Thomas Jefferson University, Philadelphia, PA, US
- Department of Cell and Molecular Biology and the Tulane Brain Institute, Tulane University, New Orleans, LA, US
| | - Edwin R Chapman
- Department of Neuroscience, University of Wisconsin-Madison, Madison, WI, US
- Howard Hughes Medical Institute, Madison, WI, US
| | - Taekjip Ha
- Department of Biomedical Engineering, School of Medicine, Johns Hopkins University, Baltimore, MD, US
- Department of Biophysics and Biophysical Chemistry, School of Medicine, Johns Hopkins University, Baltimore, MD, US
- Department of Biophysics, Johns Hopkins University, Baltimore, MD, US
- Howard Hughes Medical Institute, Baltimore, MD, US
| | - Shigeki Watanabe
- Department of Cell Biology, School of Medicine, Johns Hopkins University, Baltimore, MD, US.
- Center for Cell Dynamics, School of Medicine, Johns Hopkins University, Baltimore, MD, US.
- Solomon H. Snyder Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, MD, US.
| | - Jian Liu
- Department of Cell Biology, School of Medicine, Johns Hopkins University, Baltimore, MD, US.
- Center for Cell Dynamics, School of Medicine, Johns Hopkins University, Baltimore, MD, US.
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36
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Ghose A, Pullarkat P. The role of mechanics in axonal stability and development. Semin Cell Dev Biol 2023; 140:22-34. [PMID: 35786351 PMCID: PMC7615100 DOI: 10.1016/j.semcdb.2022.06.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 06/05/2022] [Accepted: 06/13/2022] [Indexed: 01/28/2023]
Abstract
Much of the focus of neuronal cell biology has been devoted to growth cone guidance, synaptogenesis, synaptic activity, plasticity, etc. The axonal shaft too has received much attention, mainly for its astounding ability to transmit action potentials and the transport of material over long distances. For these functions, the axonal cytoskeleton and membrane have been often assumed to play static structural roles. Recent experiments have changed this view by revealing an ultrastructure much richer in features than previously perceived and one that seems to be maintained at a dynamic steady state. The role of mechanics in this is only beginning to be broadly appreciated and appears to involve passive and active modes of coupling different biopolymer filaments, filament turnover dynamics and membrane biophysics. Axons, being unique cellular processes in terms of high aspect ratios and often extreme lengths, also exhibit unique passive mechanical properties that might have evolved to stabilize them under mechanical stress. In this review, we summarize the experiments that have exposed some of these features. It is our view that axonal mechanics deserves much more attention not only due to its significance in the development and maintenance of the nervous system but also due to the susceptibility of axons to injury and neurodegeneration.
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Affiliation(s)
- Aurnab Ghose
- Indian Institute of Science Education and Research, Pune 411 008, India.
| | - Pramod Pullarkat
- Raman Research Institute, C. V. Raman Avenue, Bengaluru 560 080, India.
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37
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Ratajczak AM, Sasidharan S, Rivera Gonzalez XI, Miller EJ, Socrier L, Anthony AA, Honerkamp-Smith AR. Measuring flow-mediated protein drift across stationary supported lipid bilayers. Biophys J 2023; 122:1720-1731. [PMID: 37020419 PMCID: PMC10183372 DOI: 10.1016/j.bpj.2023.03.042] [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: 11/11/2022] [Revised: 03/13/2023] [Accepted: 03/29/2023] [Indexed: 04/07/2023] Open
Abstract
Fluid flow near biological membranes influences cell functions such as development, motility, and environmental sensing. Flow can laterally transport extracellular membrane proteins located at the cell-fluid interface. To determine whether this transport contributes to flow signaling in cells, quantitative knowledge of the forces acting on membrane proteins is required. Here, we demonstrate a method for measuring flow-mediated lateral transport of lipid-anchored proteins. We rupture giant unilamellar vesicles to form discrete patches of supported membrane inside rectangular microchannels and then allow proteins to bind to the upper surface of the membrane. While applying flow, we observe the formation of protein concentration gradients that span the membrane patch. By observing how these gradients dynamically respond to changes in applied shear stress, we determine the flow mobility of the lipid-anchored protein. We use simplified model membranes and proteins to demonstrate our method's sensitivity and reproducibility. Our intention was to design a quantitative, reliable method and analysis for protein mobility that we will use to compare flow transport for a variety of proteins, lipid anchors, and membranes in model systems and on living cells.
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Affiliation(s)
| | | | | | - Ethan J Miller
- Department of Physics, Lehigh University, Bethlehem, Pennsylvania
| | - Larissa Socrier
- Department of Physics, Lehigh University, Bethlehem, Pennsylvania
| | - Autumn A Anthony
- Department of Physics, Lehigh University, Bethlehem, Pennsylvania
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38
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Day CA, Kang M. The Utility of Fluorescence Recovery after Photobleaching (FRAP) to Study the Plasma Membrane. MEMBRANES 2023; 13:membranes13050492. [PMID: 37233553 DOI: 10.3390/membranes13050492] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 04/01/2023] [Accepted: 04/27/2023] [Indexed: 05/27/2023]
Abstract
The plasma membrane of mammalian cells is involved in a wide variety of cellular processes, including, but not limited to, endocytosis and exocytosis, adhesion and migration, and signaling. The regulation of these processes requires the plasma membrane to be highly organized and dynamic. Much of the plasma membrane organization exists at temporal and spatial scales that cannot be directly observed with fluorescence microscopy. Therefore, approaches that report on the membrane's physical parameters must often be utilized to infer membrane organization. As discussed here, diffusion measurements are one such approach that has allowed researchers to understand the subresolution organization of the plasma membrane. Fluorescence recovery after photobleaching (or FRAP) is the most widely accessible method for measuring diffusion in a living cell and has proven to be a powerful tool in cell biology research. Here, we discuss the theoretical underpinnings that allow diffusion measurements to be used in elucidating the organization of the plasma membrane. We also discuss the basic FRAP methodology and the mathematical approaches for deriving quantitative measurements from FRAP recovery curves. FRAP is one of many methods used to measure diffusion in live cell membranes; thus, we compare FRAP with two other popular methods: fluorescence correlation microscopy and single-particle tracking. Lastly, we discuss various plasma membrane organization models developed and tested using diffusion measurements.
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Affiliation(s)
- Charles A Day
- Hormel Institute, University of Minnesota, Austin, MN 55912, USA
- Mayo Clinic, Rochester, MN 55902, USA
| | - Minchul Kang
- Department of Mathematics, Texas A&M-Commerce, Commerce, TX 75428, USA
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39
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Sáez P, Venturini C. Positive, negative and controlled durotaxis. SOFT MATTER 2023; 19:2993-3001. [PMID: 37016959 DOI: 10.1039/d2sm01326f] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Cell migration is a physical process central to life. Among others, it regulates embryogenesis, tissue regeneration, and tumor growth. Therefore, understanding and controlling cell migration represent fundamental challenges in science. Specifically, the ability of cells to follow stiffness gradients, known as durotaxis, is ubiquitous across most cell types. Even so, certain cells follow positive stiffness gradients while others move along negative gradients. How the physical mechanisms involved in cell migration work to enable a wide range of durotactic responses is still poorly understood. Here, we provide a mechanistic rationale for durotaxis by integrating stochastic clutch models for cell adhesion with an active gel theory of cell migration. We show that positive and negative durotaxis found across cell types are explained by asymmetries in the cell adhesion dynamics. We rationalize durotaxis by asymmetric mechanotransduction in the cell adhesion behavior that further polarizes the intracellular retrograde flow and the protruding velocity at the cell membrane. Our theoretical framework confirms previous experimental observations and explains positive and negative durotaxis. Moreover, we show how durotaxis can be engineered to manipulate cell migration, which has important implications in biology, medicine, and bioengineering.
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Affiliation(s)
- P Sáez
- Laboratori de Càlcul Numèric (LaCaN), Universitat Politècnica de Catalunya, Barcelona, Spain.
- E.T.S. de Ingeniería de Caminos, Universitat Politècnica de Catalunya, Barcelona, Spain
- Institut de Matemàtiques de la UPC-BarcelonaTech (IMTech), Universitat Politècnica de Catalunya, Barcelona, Spain
| | - C Venturini
- Laboratori de Càlcul Numèric (LaCaN), Universitat Politècnica de Catalunya, Barcelona, Spain.
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40
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Deng Y, Yang X, Yan T, Xu W, Li J, Niu R, Zhao R, Wang H, Wang H, Chen T, Guo M, Wang W, Liu D. Ultrasound-induced cell disintegration and its ultrastructure characterization for the valorisation of Chlorella pyrenoidosa protein. BIORESOURCE TECHNOLOGY 2023; 381:129046. [PMID: 37044154 DOI: 10.1016/j.biortech.2023.129046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 04/06/2023] [Accepted: 04/09/2023] [Indexed: 05/08/2023]
Abstract
Chlorella pyrenoidosa (CP) has great potential for feeding future demands in food, environment, energy, and pharmaceuticals. To achieve this goal, the exploitation of emerging efficient technique such as ultrasound-assisted extraction (UAE) for CP nutrient enrichment is crucial. Here, UAE is deployed for high-efficient CP protein (CPP) valorisation. Compared to conventional solvent extraction (CSE), remarkable mass transfer enhancements with 9-time protein yields and 3-time extraction rate are achieved by ultrasonic cavitation in UAE, indicating UAE can drastically shift intracellular nutrients including proteins and pigments to solvent. Cell morphology and ultrastructure show the different responses of cell wall and membrane, indicating that the cell membrane may play a role in the extraction process, based on which the extremely-low efficiency of CSE and high efficiency of UAE are highlighted. This study provides a solution for future food crisis by extracting CPP and may open a new discussion field in ultrasonic extraction.
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Affiliation(s)
- Yong Deng
- College of Biosystems Engineering and Food Science, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang Engineering Laboratory of Food Technology and Equipment, Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China
| | - Xiaoling Yang
- College of Biosystems Engineering and Food Science, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang Engineering Laboratory of Food Technology and Equipment, Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China
| | - Tianyi Yan
- College of Biosystems Engineering and Food Science, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang Engineering Laboratory of Food Technology and Equipment, Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China
| | - Weidong Xu
- College of Biosystems Engineering and Food Science, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang Engineering Laboratory of Food Technology and Equipment, Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China
| | - Jiaheng Li
- College of Biosystems Engineering and Food Science, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang Engineering Laboratory of Food Technology and Equipment, Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China
| | - Ruihao Niu
- College of Biosystems Engineering and Food Science, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang Engineering Laboratory of Food Technology and Equipment, Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China
| | - Runan Zhao
- College of Biosystems Engineering and Food Science, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang Engineering Laboratory of Food Technology and Equipment, Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China
| | - Han Wang
- College of Biosystems Engineering and Food Science, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang Engineering Laboratory of Food Technology and Equipment, Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China
| | - Hao Wang
- College of Biosystems Engineering and Food Science, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang Engineering Laboratory of Food Technology and Equipment, Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China
| | - Tingting Chen
- College of Biosystems Engineering and Food Science, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang Engineering Laboratory of Food Technology and Equipment, Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China
| | - Mingming Guo
- College of Biosystems Engineering and Food Science, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang Engineering Laboratory of Food Technology and Equipment, Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China; Innovation Center of Yangtze River Delta, Zhejiang University, Jiashan 314100, China; Ningbo Research Institute, Zhejiang University, Ningbo 315100, China
| | - Wenjun Wang
- College of Biosystems Engineering and Food Science, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang Engineering Laboratory of Food Technology and Equipment, Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China; Innovation Center of Yangtze River Delta, Zhejiang University, Jiashan 314100, China; Ningbo Research Institute, Zhejiang University, Ningbo 315100, China
| | - Donghong Liu
- College of Biosystems Engineering and Food Science, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang Engineering Laboratory of Food Technology and Equipment, Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China; Innovation Center of Yangtze River Delta, Zhejiang University, Jiashan 314100, China; Ningbo Research Institute, Zhejiang University, Ningbo 315100, China.
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41
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Itoh T, Tsujita K. Exploring membrane mechanics: The role of membrane-cortex attachment in cell dynamics. Curr Opin Cell Biol 2023; 81:102173. [PMID: 37224683 DOI: 10.1016/j.ceb.2023.102173] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/03/2023] [Accepted: 04/24/2023] [Indexed: 05/26/2023]
Abstract
The role of plasma membrane (PM) tension in cell dynamics has gained increasing interest in recent years to understand the mechanism by which individual cells regulate their dynamic behavior. Membrane-to-cortex attachment (MCA) is a component of apparent PM tension, and its assembly and disassembly determine the direction of cell motility, controlling the driving forces of migration. There is also evidence that membrane tension plays a role in malignant cancer cell metastasis and stem cell differentiation. Here, we review recent important discoveries that explore the role of membrane tension in the regulation of diverse cellular processes, and discuss the mechanisms of cell dynamics regulated by this physical parameter.
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Affiliation(s)
- Toshiki Itoh
- Biosignal Research Center, Kobe University, Kobe, Hyogo, 657-8501, Japan; Division of Membrane Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe, Hyogo, 650-0017, Japan.
| | - Kazuya Tsujita
- Biosignal Research Center, Kobe University, Kobe, Hyogo, 657-8501, Japan; Division of Membrane Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe, Hyogo, 650-0017, Japan.
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42
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Zuo J, Zhu E, Yin W, Yao C, Liao J, Ping X, Zhu Y, Cai X, Rao Y, Feng H, Zhang K, Qian Z. Long-term spatiotemporal and highly specific imaging of the plasma membrane of diverse plant cells using a near-infrared AIE probe. Chem Sci 2023; 14:2139-2148. [PMID: 36845931 PMCID: PMC9945320 DOI: 10.1039/d2sc05727a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Accepted: 01/19/2023] [Indexed: 01/21/2023] Open
Abstract
Fluorescent probes are valuable tools to visualize plasma membranes intuitively and clearly and their related physiological processes in a spatiotemporal manner. However, most existing probes have only realized the specific staining of the plasma membranes of animal/human cells within a very short time period, while almost no fluorescent probes have been developed for the long-term imaging of the plasma membranes of plant cells. Herein, we designed an AIE-active probe with NIR emission to achieve four-dimensional spatiotemporal imaging of the plasma membranes of plant cells based on a collaboration approach involving multiple strategies, demonstrated long-term real-time monitoring of morphological changes of plasma membranes for the first time, and further proved its wide applicability to plant cells of different types and diverse plant species. In the design concept, three effective strategies including the similarity and intermiscibility principle, antipermeability strategy and strong electrostatic interactions were combined to allow the probe to specifically target and anchor the plasma membrane for an ultralong amount of time on the premise of guaranteeing its sufficiently high aqueous solubility. The designed APMem-1 can quickly penetrate cell walls to specifically stain the plasma membranes of all plant cells in a very short time with advanced features (ultrafast staining, wash-free, and desirable biocompatibility) and the probe shows excellent plasma membrane specificity without staining other areas of the cell in comparison to commercial FM dyes. The longest imaging time of APMem-1 can be up to 10 h with comparable performance in both imaging contrast and imaging integrity. The validation experiments on different types of plant cells and diverse plants convincingly proved the universality of APMem-1. The development of plasma membrane probes with four-dimensional spatial and ultralong-term imaging ability provides a valuable tool to monitor the dynamic processes of plasma membrane-related events in an intuitive and real-time manner.
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Affiliation(s)
- Jiaqi Zuo
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Material Sciences, Zhejiang Normal University Yingbin Road 688 Jinhua 321004 China
| | - Engao Zhu
- College of Life Sciences, Zhejiang Normal University Yingbin Road 688 Jinhua 321004 China
| | - Wenjing Yin
- College of Life Sciences, Zhejiang Normal University Yingbin Road 688 Jinhua 321004 China
| | - Chuangye Yao
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Material Sciences, Zhejiang Normal University Yingbin Road 688 Jinhua 321004 China
| | - Jiajia Liao
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Material Sciences, Zhejiang Normal University Yingbin Road 688 Jinhua 321004 China
| | - Xinni Ping
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Material Sciences, Zhejiang Normal University Yingbin Road 688 Jinhua 321004 China
| | - Yuqing Zhu
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Material Sciences, Zhejiang Normal University Yingbin Road 688 Jinhua 321004 China
| | - Xuting Cai
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Material Sciences, Zhejiang Normal University Yingbin Road 688 Jinhua 321004 China
| | - Yuchun Rao
- College of Life Sciences, Zhejiang Normal University Yingbin Road 688 Jinhua 321004 China
| | - Hui Feng
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Material Sciences, Zhejiang Normal University Yingbin Road 688 Jinhua 321004 China
| | - Kewei Zhang
- College of Life Sciences, Zhejiang Normal University Yingbin Road 688 Jinhua 321004 China
| | - Zhaosheng Qian
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Material Sciences, Zhejiang Normal University Yingbin Road 688 Jinhua 321004 China
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43
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Lachuer H, Le L, Lévêque-Fort S, Goud B, Schauer K. Spatial organization of lysosomal exocytosis relies on membrane tension gradients. Proc Natl Acad Sci U S A 2023; 120:e2207425120. [PMID: 36800388 PMCID: PMC9974462 DOI: 10.1073/pnas.2207425120] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 12/17/2022] [Indexed: 02/18/2023] Open
Abstract
Lysosomal exocytosis is involved in many key cellular processes but its spatiotemporal regulation is poorly known. Using total internal reflection fluorescence microscopy (TIRFM) and spatial statistics, we observed that lysosomal exocytosis is not random at the adhesive part of the plasma membrane of RPE1 cells but clustered at different scales. Although the rate of exocytosis is regulated by the actin cytoskeleton, neither interfering with actin or microtubule dynamics by drug treatments alters its spatial organization. Exocytosis events partially co-appear at focal adhesions (FAs) and their clustering is reduced upon removal of FAs. Changes in membrane tension following a hypo-osmotic shock or treatment with methyl-β-cyclodextrin were found to increase clustering. To investigate the link between FAs and membrane tension, cells were cultured on adhesive ring-shaped micropatterns, which allow to control the spatial organization of FAs. By using a combination of TIRFM and fluorescence lifetime imaging microscopy (FLIM), we revealed the existence of a radial gradient in membrane tension. By changing the diameter of micropatterned substrates, we further showed that this gradient as well as the extent of exocytosis clustering can be controlled. Together, our data indicate that the spatial clustering of lysosomal exocytosis relies on membrane tension patterning controlled by the spatial organization of FAs.
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Affiliation(s)
- Hugo Lachuer
- Institut Curie, Paris Sciences et Lettres Research University, CNRS UMR 144 Cell Biology and Cancer, 75005Paris, France
| | - Laurent Le
- Université Paris-Saclay, CNRS, Institut des Sciences Moléculaires d'Orsay91405, Orsay, France
| | - Sandrine Lévêque-Fort
- Université Paris-Saclay, CNRS, Institut des Sciences Moléculaires d'Orsay91405, Orsay, France
| | - Bruno Goud
- Institut Curie, Paris Sciences et Lettres Research University, CNRS UMR 144 Cell Biology and Cancer, 75005Paris, France
| | - Kristine Schauer
- Institut Curie, Paris Sciences et Lettres Research University, CNRS UMR 144 Cell Biology and Cancer, 75005Paris, France
- Tumor Cell Dynamics Unit, Inserm U1279 Gustave Roussy Institute, Université Paris-Saclay, Villejuif94800, France
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44
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Young MN, Sindoni MJ, Lewis AH, Zauscher S, Grandl J. The energetics of rapid cellular mechanotransduction. Proc Natl Acad Sci U S A 2023; 120:e2215747120. [PMID: 36795747 PMCID: PMC9974467 DOI: 10.1073/pnas.2215747120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Accepted: 01/18/2023] [Indexed: 02/17/2023] Open
Abstract
Cells throughout the human body detect mechanical forces. While it is known that the rapid (millisecond) detection of mechanical forces is mediated by force-gated ion channels, a detailed quantitative understanding of cells as sensors of mechanical energy is still lacking. Here, we combine atomic force microscopy with patch-clamp electrophysiology to determine the physical limits of cells expressing the force-gated ion channels (FGICs) Piezo1, Piezo2, TREK1, and TRAAK. We find that, depending on the ion channel expressed, cells can function either as proportional or nonlinear transducers of mechanical energy and detect mechanical energies as little as ~100 fJ, with a resolution of up to ~1 fJ. These specific energetic values depend on cell size, channel density, and cytoskeletal architecture. We also make the surprising discovery that cells can transduce forces either nearly instantaneously (<1 ms) or with a substantial time delay (~10 ms). Using a chimeric experimental approach and simulations, we show how such delays can emerge from channel-intrinsic properties and the slow diffusion of tension in the membrane. Overall, our experiments reveal the capabilities and limits of cellular mechanosensing and provide insights into molecular mechanisms that different cell types may employ to specialize for their distinct physiological roles.
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Affiliation(s)
- Michael N. Young
- Department of Neurobiology, Duke University Medical Center, Durham, NC27710
| | - Michael J. Sindoni
- Department of Neurobiology, Duke University Medical Center, Durham, NC27710
| | - Amanda H. Lewis
- Department of Neurobiology, Duke University Medical Center, Durham, NC27710
| | - Stefan Zauscher
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC27710
| | - Jörg Grandl
- Department of Neurobiology, Duke University Medical Center, Durham, NC27710
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45
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Saha T, Heuer A, Galic M. Systematic analysis of curvature-dependent lipid dynamics in a stochastic 3D membrane model. SOFT MATTER 2023; 19:1330-1341. [PMID: 36692259 DOI: 10.1039/d2sm01260j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
To minimize the free energy of the system, lipid membranes display curvature-dependent rearrangements at the local and global scale. The optimal membrane shape is generally approximated by averaging the curvature preference of individual lipids across the whole surface. Potential stress due to imperfections in lipid packing caused by local lipid inhomogeneities, however, is frequently neglected. Here, we developed a stochastic 3D membrane model to investigate the relevance of this parameter for shape-dependent lipid and membrane dynamics. A systematic analysis of the discretized Helfrich type Hamiltonian indicates that stress-energy arising from imperfections in packing is analogous to van der Waals interactions, jointly determining membrane shape and localization of curvature-sensitive lipids based on their relative strengths. Insights from this work can be used to characterize natural and design synthetic agents for membrane-shape changes.
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Affiliation(s)
- Tanumoy Saha
- Institute of Medical Physics and Biophysics, University of Muenster, Germany.
- Cells in Motion' Interfaculty Centre, University of Muenster, Germany.
- CIM-IMPRS Graduate School, Muenster, Germany
| | - Andreas Heuer
- Cells in Motion' Interfaculty Centre, University of Muenster, Germany.
- Institute of Physical Chemistry, University of Muenster, Germany
| | - Milos Galic
- Institute of Medical Physics and Biophysics, University of Muenster, Germany.
- Cells in Motion' Interfaculty Centre, University of Muenster, Germany.
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46
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Gerganova V, Martin SG. Going with the membrane flow: the impact of polarized secretion on bulk plasma membrane flows. FEBS J 2023; 290:669-676. [PMID: 34797957 PMCID: PMC10078680 DOI: 10.1111/febs.16287] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 11/07/2021] [Accepted: 11/18/2021] [Indexed: 02/04/2023]
Abstract
Even the simplest cells show a remarkable degree of intracellular patterning. Like developing multicellular organisms, single cells break symmetry to establish polarity axes, pattern their cortex and interior, and undergo morphogenesis to acquire sometimes complex shapes. Symmetry-breaking and molecular patterns can be established through coupling of negative and positive feedback reactions in biochemical reaction-diffusion systems. Physical forces, perhaps best studied in the contraction of the metazoan acto-myosin cortex, which induces cortical and cytoplasmic flows, also serve to pattern-associated components. A less investigated physical perturbation is the in-plane flow of plasma membrane material caused by membrane trafficking. In this review, we discuss how bulk membrane flows can be generated at sites of active polarized secretion and growth, how they affect the distribution of membrane-associated proteins, and how they may be harnessed for patterning and directional movement in cells across the tree of life.
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Affiliation(s)
- Veneta Gerganova
- Department of Fundamental Microbiology, University of Lausanne, Switzerland
| | - Sophie G Martin
- Department of Fundamental Microbiology, University of Lausanne, Switzerland
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47
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Abstract
Plasma membrane tension functions as a global physical organizer of cellular activities. Technical limitations of current membrane tension measurement techniques have hampered in-depth investigation of cellular membrane biophysics and the role of plasma membrane tension in regulating cellular processes. Here, we develop an optical membrane tension reporter by repurposing an E. coli mechanosensitive channel via insertion of circularly permuted GFP (cpGFP), which undergoes a large conformational rearrangement associated with channel activation and thus fluorescence intensity changes under increased membrane tension.
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Affiliation(s)
- Yen-Yu Hsu
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Agnes M Resto Irizarry
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Jianping Fu
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Cell & Developmental Biology, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Allen P Liu
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109, United States
- Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, Michigan 48109, United States
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48
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Li JH, Trivedi V, Diz-Muñoz A. Understanding the interplay of membrane trafficking, cell surface mechanics, and stem cell differentiation. Semin Cell Dev Biol 2023; 133:123-134. [PMID: 35641408 PMCID: PMC9703995 DOI: 10.1016/j.semcdb.2022.05.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 04/08/2022] [Accepted: 05/14/2022] [Indexed: 01/17/2023]
Abstract
Stem cells can generate a diversity of cell types during development, regeneration and adult tissue homeostasis. Differentiation changes not only the cell fate in terms of gene expression but also the physical properties and functions of cells, e.g. the secretory activity, cell shape, or mechanics. Conversely, these activities and properties can also regulate differentiation itself. Membrane trafficking is known to modulate signal transduction and thus has the potential to control stem cell differentiation. On the other hand, membrane trafficking, particularly from and to the plasma membrane, depends on the mechanical properties of the cell surface such as tension within the plasma membrane or the cortex. Indeed, recent findings demonstrate that cell surface mechanics can also control cell fate. Here, we review the bidirectional relationships between these three fundamental cellular functions, i.e. membrane trafficking, cell surface mechanics, and stem cell differentiation. Furthermore, we discuss commonly used methods in each field and how combining them with new tools will enhance our understanding of their interplay. Understanding how membrane trafficking and cell surface mechanics can guide stem cell fate holds great potential as these concepts could be exploited for directed differentiation of stem cells for the fields of tissue engineering and regenerative medicine.
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Affiliation(s)
- Jia Hui Li
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstraße 1, Heidelberg 69117, Germany
| | - Vikas Trivedi
- EMBL, PRBB, Dr. Aiguader, 88, Barcelona 08003, Spain,Developmental Biology Unit, EMBL, Meyerhofstraße 1, Heidelberg 69117, Germany
| | - Alba Diz-Muñoz
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstraße 1, Heidelberg 69117, Germany.
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49
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Caveolin-1 dolines form a distinct and rapid caveolae-independent mechanoadaptation system. Nat Cell Biol 2023; 25:120-133. [PMID: 36543981 PMCID: PMC9859760 DOI: 10.1038/s41556-022-01034-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 10/21/2022] [Indexed: 12/24/2022]
Abstract
In response to different types and intensities of mechanical force, cells modulate their physical properties and adapt their plasma membrane (PM). Caveolae are PM nano-invaginations that contribute to mechanoadaptation, buffering tension changes. However, whether core caveolar proteins contribute to PM tension accommodation independently from the caveolar assembly is unknown. Here we provide experimental and computational evidence supporting that caveolin-1 confers deformability and mechanoprotection independently from caveolae, through modulation of PM curvature. Freeze-fracture electron microscopy reveals that caveolin-1 stabilizes non-caveolar invaginations-dolines-capable of responding to low-medium mechanical forces, impacting downstream mechanotransduction and conferring mechanoprotection to cells devoid of caveolae. Upon cavin-1/PTRF binding, doline size is restricted and membrane buffering is limited to relatively high forces, capable of flattening caveolae. Thus, caveolae and dolines constitute two distinct albeit complementary components of a buffering system that allows cells to adapt efficiently to a broad range of mechanical stimuli.
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50
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Cairoli A, Spenlehauer A, Overby DR, Lee CF. Model of inverse bleb growth explains giant vacuole dynamics during cell mechanoadaptation. PNAS NEXUS 2022; 2:pgac304. [PMID: 36845355 PMCID: PMC9944300 DOI: 10.1093/pnasnexus/pgac304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 12/22/2022] [Indexed: 12/25/2022]
Abstract
Cells can withstand hostile environmental conditions manifest as large mechanical forces such as pressure gradients and/or shear stresses by dynamically changing their shape. Such conditions are realized in the Schlemm's canal of the eye where endothelial cells that cover the inner vessel wall are subjected to the hydrodynamic pressure gradients exerted by the aqueous humor outflow. These cells form fluid-filled dynamic outpouchings of their basal membrane called giant vacuoles. The inverses of giant vacuoles are reminiscent of cellular blebs, extracellular cytoplasmic protrusions triggered by local temporary disruption of the contractile actomyosin cortex. Inverse blebbing has also been first observed experimentally during sprouting angiogenesis, but its underlying physical mechanisms are poorly understood. Here, we hypothesize that giant vacuole formation can be described as inverse blebbing and formulate a biophysical model of this process. Our model elucidates how cell membrane mechanical properties affect the morphology and dynamics of giant vacuoles and predicts coarsening akin to Ostwald ripening between multiple invaginating vacuoles. Our results are in qualitative agreement with observations from the formation of giant vacuoles during perfusion experiments. Our model not only elucidates the biophysical mechanisms driving inverse blebbing and giant vacuole dynamics, but also identifies universal features of the cellular response to pressure loads that are relevant to many experimental contexts.
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Affiliation(s)
| | - Alice Spenlehauer
- Department of Bioengineering, Imperial College London, London SW7 2AZ, UK
| | - Darryl R Overby
- Department of Bioengineering, Imperial College London, London SW7 2AZ, UK
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