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Naganathan SR. An emerging role for tissue plasticity in developmental precision. Biochem Soc Trans 2024; 52:987-995. [PMID: 38716859 DOI: 10.1042/bst20230173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 03/21/2024] [Accepted: 04/23/2024] [Indexed: 06/27/2024]
Abstract
Reproducible tissue morphology is a fundamental feature of embryonic development. To ensure such robustness during tissue morphogenesis, inherent noise in biological processes must be buffered. While redundant genes, parallel signaling pathways and intricate network topologies are known to reduce noise, over the last few years, mechanical properties of tissues have been shown to play a vital role. Here, taking the example of somite shape changes, I will discuss how tissues are highly plastic in their ability to change shapes leading to increased precision and reproducibility.
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Affiliation(s)
- Sundar Ram Naganathan
- Department of Biological Sciences, Tata Institute of Fundamental Research, 1, Dr. Homi Bhabha Road, Colaba, Mumbai 400005, India
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2
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Dalaka E, Hill JS, Booth JHH, Popczyk A, Pulver SR, Gather MC, Schubert M. Deformable microlaser force sensing. LIGHT, SCIENCE & APPLICATIONS 2024; 13:129. [PMID: 38834554 DOI: 10.1038/s41377-024-01471-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 04/30/2024] [Accepted: 05/08/2024] [Indexed: 06/06/2024]
Abstract
Mechanical forces are key regulators of cellular behavior and function, affecting many fundamental biological processes such as cell migration, embryogenesis, immunological responses, and pathological states. Specialized force sensors and imaging techniques have been developed to quantify these otherwise invisible forces in single cells and in vivo. However, current techniques rely heavily on high-resolution microscopy and do not allow interrogation of optically dense tissue, reducing their application to 2D cell cultures and highly transparent biological tissue. Here, we introduce DEFORM, deformable microlaser force sensing, a spectroscopic technique that detects sub-nanonewton forces with unprecedented spatio-temporal resolution. DEFORM is based on the spectral analysis of laser emission from dye-doped oil microdroplets and uses the force-induced lifting of laser mode degeneracy in these droplets to detect nanometer deformations. Following validation by atomic force microscopy and development of a model that links changes in laser spectrum to applied force, DEFORM is used to measure forces in 3D and at depths of hundreds of microns within tumor spheroids and late-stage Drosophila larva. We furthermore show continuous force sensing with single-cell spatial and millisecond temporal resolution, thus paving the way for non-invasive studies of biomechanical forces in advanced stages of embryogenesis, tissue remodeling, and tumor invasion.
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Affiliation(s)
- Eleni Dalaka
- Centre of Biophotonics, SUPA, School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, UK
- Institute for Bioengineering of Catalonia, Barcelona, Spain
| | - Joseph S Hill
- Centre of Biophotonics, SUPA, School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, UK
- Humboldt Centre for Nano- and Biophotonics, Department of Chemistry, University of Cologne, Köln, Germany
| | - Jonathan H H Booth
- Humboldt Centre for Nano- and Biophotonics, Department of Chemistry, University of Cologne, Köln, Germany
- School of Psychology and Neuroscience, University of St Andrews, St Mary's Quad, South Street, St Andrews, UK
| | - Anna Popczyk
- Humboldt Centre for Nano- and Biophotonics, Department of Chemistry, University of Cologne, Köln, Germany
| | - Stefan R Pulver
- School of Psychology and Neuroscience, University of St Andrews, St Mary's Quad, South Street, St Andrews, UK
| | - Malte C Gather
- Centre of Biophotonics, SUPA, School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, UK.
- Humboldt Centre for Nano- and Biophotonics, Department of Chemistry, University of Cologne, Köln, Germany.
| | - Marcel Schubert
- Humboldt Centre for Nano- and Biophotonics, Department of Chemistry, University of Cologne, Köln, Germany.
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3
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Uechi H, Kuranaga E. Underlying mechanisms that ensure actomyosin-mediated directional remodeling of cell-cell contacts for multicellular movement: Tricellular junctions and negative feedback as new aspects underlying actomyosin-mediated directional epithelial morphogenesis: Tricellular junctions and negative feedback as new aspects underlying actomyosin-mediated directional epithelial morphogenesis. Bioessays 2023; 45:e2200211. [PMID: 36929512 DOI: 10.1002/bies.202200211] [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: 10/31/2022] [Revised: 02/27/2023] [Accepted: 03/01/2023] [Indexed: 03/18/2023]
Abstract
Actomyosin (actin-myosin II complex)-mediated contractile forces are central to the generation of multifaceted uni- and multi-cellular material properties and dynamics such as cell division, migration, and tissue morphogenesis. In the present article, we summarize our recent researches addressing molecular mechanisms that ensure actomyosin-mediated directional cell-cell junction remodeling, either shortening or extension, driving cell rearrangement for epithelial morphogenesis. Genetic perturbation clarified two points concerning cell-cell junction remodeling: an inhibitory mechanism against negative feedback in which actomyosin contractile forces, which are well known to induce cell-cell junction shortening, can concomitantly alter actin dynamics, oppositely leading to perturbation of the shortening; and tricellular junctions as a point that organizes extension of new cell-cell junctions after shortening. These findings highlight the notion that cells develop underpinning mechanisms to transform the multi-tasking property of actomyosin contractile forces into specific and proper cellular dynamics in space and time.
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Affiliation(s)
- Hiroyuki Uechi
- Laboratory for Histogenetic Dynamics, Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Erina Kuranaga
- Laboratory for Histogenetic Dynamics, Graduate School of Life Sciences, Tohoku University, Sendai, Japan
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4
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Wang J, Michel M, Bialas L, Pierini G, Dahmann C. Preferential recruitment and stabilization of Myosin II at compartment boundaries in Drosophila. J Cell Sci 2023; 136:286802. [PMID: 36718636 PMCID: PMC10022687 DOI: 10.1242/jcs.260447] [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: 07/21/2022] [Accepted: 01/23/2023] [Indexed: 02/01/2023] Open
Abstract
The regulation of mechanical tension exerted at cell junctions guides cell behavior during tissue formation and homeostasis. Cell junctions along compartment boundaries, which are lineage restrictions separating cells with different fates and functions within tissues, are characterized by increased mechanical tension compared to that of cell junctions in the bulk of the tissue. Mechanical tension depends on the actomyosin cytoskeleton; however, the mechanisms by which mechanical tension is locally increased at cell junctions along compartment boundaries remain elusive. Here, we show that non-muscle Myosin II and F-actin transiently accumulate and mechanical tension is increased at cell junctions along the forming anteroposterior compartment boundary in the Drosophila melanogaster pupal abdominal epidermis. Fluorescence recovery after photobleaching experiments showed that Myosin II accumulation correlated with its increased stabilization at these junctions. Moreover, photoconversion experiments indicated that Myosin II is preferentially recruited within cells to junctions along the compartment boundary. Our results indicate that the preferential recruitment and stabilization of Myosin II contribute to the initial build-up of mechanical tension at compartment boundaries.
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Affiliation(s)
- Jing Wang
- School of Science, Technische Universität Dresden, 01062 Dresden, Germany
| | - Marcus Michel
- School of Science, Technische Universität Dresden, 01062 Dresden, Germany
| | - Lisa Bialas
- School of Science, Technische Universität Dresden, 01062 Dresden, Germany
| | - Giulia Pierini
- School of Science, Technische Universität Dresden, 01062 Dresden, Germany
| | - Christian Dahmann
- School of Science, Technische Universität Dresden, 01062 Dresden, Germany.,Cluster of Excellence Physics of Life, Technische Universität Dresden, 01062 Dresden, Germany
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5
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Cell polarity and extrusion: How to polarize extrusion and extrude misspolarized cells? Curr Top Dev Biol 2023; 154:131-167. [PMID: 37100516 DOI: 10.1016/bs.ctdb.2023.02.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
Abstract
The barrier function of epithelia is one of the cornerstones of the body plan organization of metazoans. It relies on the polarity of epithelial cells which organizes along the apico-basal axis the mechanical properties, signaling as well as transport. This barrier function is however constantly challenged by the fast turnover of epithelia occurring during morphogenesis or adult tissue homeostasis. Yet, the sealing property of the tissue can be maintained thanks to cell extrusion: a series of remodeling steps involving the dying cell and its neighbors leading to seamless cell expulsion. Alternatively, the tissue architecture can also be challenged by local damages or the emergence of mutant cells that may alter its organization. This includes mutants of the polarity complexes which can generate neoplastic overgrowths or be eliminated by cell competition when surrounded by wild type cells. In this review, we will provide an overview of the regulation of cell extrusion in various tissues focusing on the relationship between cell polarity, cell organization and the direction of cell expulsion. We will then describe how local perturbations of polarity can also trigger cell elimination either by apoptosis or by cell exclusion, focusing specifically on how polarity defects can be directly causal to cell elimination. Overall, we propose a general framework connecting the influence of polarity on cell extrusion and its contribution to aberrant cell elimination.
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6
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Inhibition of negative feedback for persistent epithelial cell-cell junction contraction by p21-activated kinase 3. Nat Commun 2022; 13:3520. [PMID: 35725726 PMCID: PMC9209458 DOI: 10.1038/s41467-022-31252-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 06/12/2022] [Indexed: 11/25/2022] Open
Abstract
Actin-mediated mechanical forces are central drivers of cellular dynamics. They generate protrusive and contractile dynamics, the latter of which are induced in concert with myosin II bundled at the site of contraction. These dynamics emerge concomitantly in tissues and even each cell; thus, the tight regulation of such bidirectional forces is important for proper cellular deformation. Here, we show that contractile dynamics can eventually disturb cell–cell junction contraction in the absence of p21-activated kinase 3 (Pak3). Upon Pak3 depletion, contractility induces the formation of abnormal actin protrusions at the shortening junctions, which causes decrease in E-cadherin levels at the adherens junctions and mislocalization of myosin II at the junctions before they enough shorten, compromising completion of junction shortening. Overexpressing E-cadherin restores myosin II distribution closely placed at the junctions and junction contraction. Our results suggest that contractility both induces and perturbs junction contraction and that the attenuation of such perturbations by Pak3 facilitates persistent junction shortening. Actin and myosin operate at cell–cell junctions during junctional shortening. Here the authors show that prolonged actomyosin contractility can compromise junctional shortening, and that Pak3 is required for attenuation of abnormal active protrusive structure and thus keeps junction contraction, appropriate E-cadherin distribution, and junction shortening in Drosophila.
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7
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Mierke CT. Viscoelasticity, Like Forces, Plays a Role in Mechanotransduction. Front Cell Dev Biol 2022; 10:789841. [PMID: 35223831 PMCID: PMC8864183 DOI: 10.3389/fcell.2022.789841] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 01/11/2022] [Indexed: 12/13/2022] Open
Abstract
Viscoelasticity and its alteration in time and space has turned out to act as a key element in fundamental biological processes in living systems, such as morphogenesis and motility. Based on experimental and theoretical findings it can be proposed that viscoelasticity of cells, spheroids and tissues seems to be a collective characteristic that demands macromolecular, intracellular component and intercellular interactions. A major challenge is to couple the alterations in the macroscopic structural or material characteristics of cells, spheroids and tissues, such as cell and tissue phase transitions, to the microscopic interferences of their elements. Therefore, the biophysical technologies need to be improved, advanced and connected to classical biological assays. In this review, the viscoelastic nature of cytoskeletal, extracellular and cellular networks is presented and discussed. Viscoelasticity is conceptualized as a major contributor to cell migration and invasion and it is discussed whether it can serve as a biomarker for the cells’ migratory capacity in several biological contexts. It can be hypothesized that the statistical mechanics of intra- and extracellular networks may be applied in the future as a powerful tool to explore quantitatively the biomechanical foundation of viscoelasticity over a broad range of time and length scales. Finally, the importance of the cellular viscoelasticity is illustrated in identifying and characterizing multiple disorders, such as cancer, tissue injuries, acute or chronic inflammations or fibrotic diseases.
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8
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Nestor-Bergmann A, Blanchard GB, Hervieux N, Fletcher AG, Étienne J, Sanson B. Adhesion-regulated junction slippage controls cell intercalation dynamics in an Apposed-Cortex Adhesion Model. PLoS Comput Biol 2022; 18:e1009812. [PMID: 35089922 PMCID: PMC8887740 DOI: 10.1371/journal.pcbi.1009812] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 03/01/2022] [Accepted: 01/06/2022] [Indexed: 02/02/2023] Open
Abstract
Cell intercalation is a key cell behaviour of morphogenesis and wound healing, where local cell neighbour exchanges can cause dramatic tissue deformations such as body axis extension. Substantial experimental work has identified the key molecular players facilitating intercalation, but there remains a lack of consensus and understanding of their physical roles. Existing biophysical models that represent cell-cell contacts with single edges cannot study cell neighbour exchange as a continuous process, where neighbouring cell cortices must uncouple. Here, we develop an Apposed-Cortex Adhesion Model (ACAM) to understand active cell intercalation behaviours in the context of a 2D epithelial tissue. The junctional actomyosin cortex of every cell is modelled as a continuous viscoelastic rope-loop, explicitly representing cortices facing each other at bicellular junctions and the adhesion molecules that couple them. The model parameters relate directly to the properties of the key subcellular players that drive dynamics, providing a multi-scale understanding of cell behaviours. We show that active cell neighbour exchanges can be driven by purely junctional mechanisms. Active contractility and cortical turnover in a single bicellular junction are sufficient to shrink and remove a junction. Next, a new, orthogonal junction extends passively. The ACAM reveals how the turnover of adhesion molecules regulates tension transmission and junction deformation rates by controlling slippage between apposed cell cortices. The model additionally predicts that rosettes, which form when a vertex becomes common to many cells, are more likely to occur in actively intercalating tissues with strong friction from adhesion molecules.
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Affiliation(s)
- Alexander Nestor-Bergmann
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
- * E-mail: (AN-B); (JE)
| | - Guy B. Blanchard
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Nathan Hervieux
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Alexander G. Fletcher
- School of Mathematics and Statistics and Bateson Centre, University of Sheffield, Sheffield, United Kingdom
| | - Jocelyn Étienne
- LIPHY, CNRS, Univ. Grenoble Alpes, CNRS, LIPhy, 38000 Grenoble, France
- * E-mail: (AN-B); (JE)
| | - Bénédicte Sanson
- School of Mathematics and Statistics and Bateson Centre, University of Sheffield, Sheffield, United Kingdom
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9
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Trubuil E, D'Angelo A, Solon J. Tissue mechanics in morphogenesis: Active control of tissue material properties to shape living organisms. Cells Dev 2021; 168:203777. [DOI: 10.1016/j.cdev.2022.203777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 03/01/2022] [Accepted: 03/29/2022] [Indexed: 11/17/2022]
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10
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Arslan FN, Eckert J, Schmidt T, Heisenberg CP. Holding it together: when cadherin meets cadherin. Biophys J 2021; 120:4182-4192. [PMID: 33794149 PMCID: PMC8516678 DOI: 10.1016/j.bpj.2021.03.025] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 02/12/2021] [Accepted: 03/17/2021] [Indexed: 12/21/2022] Open
Abstract
Intercellular adhesion is the key to multicellularity, and its malfunction plays an important role in various developmental and disease-related processes. Although it has been intensively studied by both biologists and physicists, a commonly accepted definition of cell-cell adhesion is still being debated. Cell-cell adhesion has been described at the molecular scale as a function of adhesion receptors controlling binding affinity, at the cellular scale as resistance to detachment forces or modulation of surface tension, and at the tissue scale as a regulator of cellular rearrangements and morphogenesis. In this review, we aim to summarize and discuss recent advances in the molecular, cellular, and theoretical description of cell-cell adhesion, ranging from biomimetic models to the complexity of cells and tissues in an organismal context. In particular, we will focus on cadherin-mediated cell-cell adhesion and the role of adhesion signaling and mechanosensation therein, two processes central for understanding the biological and physical basis of cell-cell adhesion.
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Affiliation(s)
- Feyza Nur Arslan
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Julia Eckert
- Physics of Life Processes, Leiden Institute of Physics, Leiden University, Leiden, the Netherlands
| | - Thomas Schmidt
- Physics of Life Processes, Leiden Institute of Physics, Leiden University, Leiden, the Netherlands
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11
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Casani S, Casanova J, Llimargas M. Unravelling the distinct contribution of cell shape changes and cell intercalation to tissue morphogenesis: the case of the Drosophila trachea. Open Biol 2020; 10:200329. [PMID: 33234070 PMCID: PMC7729023 DOI: 10.1098/rsob.200329] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Intercalation allows cells to exchange positions in a spatially oriented manner in an array of diverse processes, spanning convergent extension in embryonic gastrulation to the formation of tubular organs. However, given the co-occurrence of cell intercalation and changes in cell shape, it is sometimes difficult to ascertain their respective contribution to morphogenesis. A well-established model to analyse intercalation, particularly in tubular organs, is the Drosophila tracheal system. There, fibroblast growth factor (FGF) signalling at the tip of the dorsal branches generates a ‘pulling’ force believed to promote cell elongation and cell intercalation, which account for the final branch extension. Here, we used a variety of experimental conditions to study the contribution of cell elongation and cell intercalation to morphogenesis and analysed their mutual requirements. We provide evidence that cell intercalation does not require cell elongation and vice versa. We also show that the two cell behaviours are controlled by independent but simultaneous mechanisms, and that cell elongation is sufficient to account for full extension of the dorsal branch, while cell intercalation has a specific role in setting the diameter of this structure. Thus, rather than viewing changes in cell shape and cell intercalation as just redundant events that add robustness to a given morphogenetic process, we find that they can also act by contributing to different features of tissue architecture.
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Affiliation(s)
- Sandra Casani
- Institut de Biologia Molecular de Barcelona, CSIC, Parc Científic de Barcelona, Baldiri Reixac, 10-12, 08028 Barcelona, Catalonia, Spain.,Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Baldiri Reixac 10, 08028 Barcelona, Catalonia, Spain
| | - Jordi Casanova
- Institut de Biologia Molecular de Barcelona, CSIC, Parc Científic de Barcelona, Baldiri Reixac, 10-12, 08028 Barcelona, Catalonia, Spain.,Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Baldiri Reixac 10, 08028 Barcelona, Catalonia, Spain
| | - Marta Llimargas
- Institut de Biologia Molecular de Barcelona, CSIC, Parc Científic de Barcelona, Baldiri Reixac, 10-12, 08028 Barcelona, Catalonia, Spain
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12
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Tlili S, Durande M, Gay C, Ladoux B, Graner F, Delanoë-Ayari H. Migrating Epithelial Monolayer Flows Like a Maxwell Viscoelastic Liquid. PHYSICAL REVIEW LETTERS 2020; 125:088102. [PMID: 32909763 DOI: 10.1103/physrevlett.125.088102] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 07/16/2020] [Indexed: 06/11/2023]
Abstract
We perform a bidimensional Stokes experiment in an active cellular material: an autonomously migrating monolayer of Madin-Darby canine kidney epithelial cells flows around a circular obstacle within a long and narrow channel, involving an interplay between cell shape changes and neighbor rearrangements. Based on image analysis of tissue flow and coarse-grained cell anisotropy, we determine the tissue strain rate, cell deformation, and rearrangement rate fields, which are spatially heterogeneous. We find that the cell deformation and rearrangement rate fields correlate strongly, which is compatible with a Maxwell viscoelastic liquid behavior (and not with a Kelvin-Voigt viscoelastic solid behavior). The value of the associated relaxation time is measured as τ=70±15 min, is observed to be independent of obstacle size and division rate, and is increased by inhibiting myosin activity. In this experiment, the monolayer behaves as a flowing material with a Weissenberg number close to one which shows that both elastic and viscous effects can have comparable contributions in the process of collective cell migration.
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Affiliation(s)
- S Tlili
- Laboratoire Matière et Systèmes Complexes, Université de Paris-Diderot, CNRS UMR 7057, 10 rue Alice Domon et Léonie Duquet, F-75205 Paris Cedex 13, France
- Mechanobiology Institute, Department of Biological Sciences, National University of Singapore, 5A Engineering Drive, 1, 117411 Singapore
| | - M Durande
- Laboratoire Matière et Systèmes Complexes, Université de Paris-Diderot, CNRS UMR 7057, 10 rue Alice Domon et Léonie Duquet, F-75205 Paris Cedex 13, France
| | - C Gay
- Laboratoire Matière et Systèmes Complexes, Université de Paris-Diderot, CNRS UMR 7057, 10 rue Alice Domon et Léonie Duquet, F-75205 Paris Cedex 13, France
| | - B Ladoux
- Mechanobiology Institute, Department of Biological Sciences, National University of Singapore, 5A Engineering Drive, 1, 117411 Singapore
- Institut Jacques Monod, Université de Paris-Diderot, CNRS UMR 7592, 15 rue Hélène Brion, 75205 Paris Cedex 13, France
| | - F Graner
- Laboratoire Matière et Systèmes Complexes, Université de Paris-Diderot, CNRS UMR 7057, 10 rue Alice Domon et Léonie Duquet, F-75205 Paris Cedex 13, France
| | - H Delanoë-Ayari
- Univ. Lyon, Université Claude Bernard Lyon 1, CNRS UMR 5306, Institut Lumière Matière, Campus LyonTech-La Doua, Kastler building, 10 rue Ada Byron, F-69622 Villeurbanne Cedex, France
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13
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Gillard G, Röper K. Control of cell shape during epithelial morphogenesis: recent advances. Curr Opin Genet Dev 2020; 63:1-8. [PMID: 32092616 DOI: 10.1016/j.gde.2020.01.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 01/15/2020] [Accepted: 01/20/2020] [Indexed: 01/07/2023]
Abstract
Morphogenesis is an essential process by which a given tissue, organ or organism acquires its final shape. A select number of mechanisms are used in order to drive epithelial morphogenesis, including cell shape changes as well as cell death or cell division. A cell's shape results from the combination of intrinsic properties of the actomyosin and microtubule (MTs) cytoskeletons, and extrinsic properties due to physical interactions with the neighbouring environment. While we now have a good understanding of the genetic pathways and some of the signalling pathways controlling cell shape changes, the mechanical properties of cells and their role in morphogenesis remain largely unexplored. Recent improvements in microscopy techniques and the development of modelling and quantitative methods have enabled a better understanding of the bio-mechanical events controlling cell shape during morphogenesis. This review aims to highlight recent findings elegantly unravelling and quantifying the contribution of mechanical forces during morphogenesis.
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Affiliation(s)
- Ghislain Gillard
- MRC-Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH, UK.
| | - Katja Röper
- MRC-Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH, UK.
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14
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Fonseca CG, Barbacena P, Franco CA. Endothelial cells on the move: dynamics in vascular morphogenesis and disease. VASCULAR BIOLOGY 2020; 2:H29-H43. [PMID: 32935077 PMCID: PMC7487603 DOI: 10.1530/vb-20-0007] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 07/02/2020] [Indexed: 12/11/2022]
Abstract
The vascular system is a hierarchically organized network of blood vessels that play crucial roles in embryogenesis, homeostasis and disease. Blood vessels are built by endothelial cells – the cells lining the interior of blood vessels – through a process named vascular morphogenesis. Endothelial cells react to different biomechanical signals in their environment by adjusting their behavior to: (1) invade, proliferate and fuse to form new vessels (angiogenesis); (2) remodel, regress and establish a hierarchy in the network (patterning); and (3) maintain network stability (quiescence). Each step involves the coordination of endothelial cell differentiation, proliferation, polarity, migration, rearrangements and shape changes to ensure network integrity and an efficient barrier between blood and tissues. In this review, we highlighted the relevance and the mechanisms involving endothelial cell migration during different steps of vascular morphogenesis. We further present evidence on how impaired endothelial cell dynamics can contribute to pathology.
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Affiliation(s)
- Catarina G Fonseca
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.,Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal
| | - Pedro Barbacena
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Claudio A Franco
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.,Instituto de Histologia e Biologia do Desenvolvimento, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
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15
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Smith SJ, Davidson LA, Rebeiz M. Evolutionary expansion of apical extracellular matrix is required for the elongation of cells in a novel structure. eLife 2020; 9:55965. [PMID: 32338602 PMCID: PMC7266619 DOI: 10.7554/elife.55965] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 04/06/2020] [Indexed: 12/13/2022] Open
Abstract
One of the fundamental gaps in our knowledge of how novel anatomical structures evolve is understanding the origins of the morphogenetic processes that form these features. Here, we traced the cellular development of a recently evolved morphological novelty, the posterior lobe of D. melanogaster. We found that this genital outgrowth forms through extreme increases in epithelial cell height. By examining the apical extracellular matrix (aECM), we also uncovered a vast matrix associated with the developing genitalia of lobed and non-lobed species. Expression of the aECM protein Dumpy is spatially expanded in lobe-forming species, connecting the posterior lobe to the ancestrally derived aECM network. Further analysis demonstrated that Dumpy attachments are necessary for cell height increases during posterior lobe development. We propose that the aECM presents a rich reservoir for generating morphological novelty and highlights a yet unseen role for aECM in regulating extreme cell height.
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Affiliation(s)
- Sarah Jacquelyn Smith
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, United States
| | - Lance A Davidson
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, United States
| | - Mark Rebeiz
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, United States
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16
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Nonuniform growth and surface friction determine bacterial biofilm morphology on soft substrates. Proc Natl Acad Sci U S A 2020; 117:7622-7632. [PMID: 32193350 DOI: 10.1073/pnas.1919607117] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
During development, organisms acquire three-dimensional (3D) shapes with important physiological consequences. While basic mechanisms underlying morphogenesis are known in eukaryotes, it is often difficult to manipulate them in vivo. To circumvent this issue, here we present a study of developing Vibrio cholerae biofilms grown on agar substrates in which the spatiotemporal morphological patterns were altered by varying the agar concentration. Expanding biofilms are initially flat but later undergo a mechanical instability and become wrinkled. To gain mechanistic insights into this dynamic pattern-formation process, we developed a model that considers diffusion of nutrients and their uptake by bacteria, bacterial growth/biofilm matrix production, mechanical deformation of both the biofilm and the substrate, and the friction between them. Our model shows quantitative agreement with experimental measurements of biofilm expansion dynamics, and it accurately predicts two distinct spatiotemporal patterns observed in the experiments-the wrinkles initially appear either in the peripheral region and propagate inward (soft substrate/low friction) or in the central region and propagate outward (stiff substrate/high friction). Our results, which establish that nonuniform growth and friction are fundamental determinants of stress anisotropy and hence biofilm morphology, are broadly applicable to bacterial biofilms with similar morphologies and also provide insight into how other bacterial biofilms form distinct wrinkle patterns. We discuss the implications of forming undulated biofilm morphologies, which may enhance the availability of nutrients and signaling molecules and serve as a "bet hedging" strategy.
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Ferro V, Chuai M, McGloin D, Weijer CJ. Measurement of junctional tension in epithelial cells at the onset of primitive streak formation in the chick embryo via non-destructive optical manipulation. Development 2020; 147:dev.175109. [PMID: 31964776 PMCID: PMC7033729 DOI: 10.1242/dev.175109] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Accepted: 01/13/2020] [Indexed: 12/23/2022]
Abstract
Directional cell intercalations of epithelial cells during gastrulation has, in several organisms, been shown to be associated with a planar cell polarity in the organisation of the actin-myosin cytoskeleton and is postulated to reflect directional tension that drives oriented cell intercalations. We have characterised and applied a recently introduced non-destructive optical manipulation technique to measure the tension in individual epithelial cell junctions of cells in various locations and orientations in the epiblast of chick embryos in the early stages of primitive streak formation. Junctional tension of mesendoderm precursors in the epiblast is higher in junctions oriented in the direction of intercalation than in junctions oriented perpendicular to the direction of intercalation and higher than in junctions of other cells in the epiblast. The kinetic data fit best with a simple viscoelastic Maxwell model, and we find that junctional tension, and to a lesser extent viscoelastic relaxation time, are dependent on myosin activity.
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Affiliation(s)
- Valentina Ferro
- Department of Physics, School of Science and Engineering, University of Dundee, Dundee DD1 4HN, UK
| | - Manli Chuai
- School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - David McGloin
- Department of Physics, School of Science and Engineering, University of Dundee, Dundee DD1 4HN, UK
- School of Electrical and Data Engineering, University of Technology Sydney, Ultimo, NSW 2007, Australia
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18
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Cell-Size Pleomorphism Drives Aberrant Clone Dispersal in Proliferating Epithelia. Dev Cell 2019; 51:49-61.e4. [PMID: 31495693 DOI: 10.1016/j.devcel.2019.08.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Revised: 06/18/2019] [Accepted: 08/06/2019] [Indexed: 11/22/2022]
Abstract
As epithelial tissues develop, groups of cells related by descent tend to associate in clonal populations rather than dispersing within the cell layer. While this is frequently assumed to be a result of differential adhesion, precise mechanisms controlling clonal cohesiveness remain unknown. Here we employ computational simulations to modulate epithelial cell size in silico and show that junctions between small cells frequently collapse, resulting in clone-cell dispersal among larger neighbors. Consistent with similar dynamics in vivo, we further demonstrate that mosaic disruption of Drosophila Tor generates small cells and results in aberrant clone dispersal in developing wing disc epithelia. We propose a geometric basis for this phenomenon, supported in part by the observation that soap-foam cells exhibit similar size-dependent junctional rearrangements. Combined, these results establish a link between cell-size pleomorphism and the control of epithelial cell packing, with potential implications for understanding tumor cell dispersal in human disease.
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19
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Matamoro-Vidal A, Levayer R. Multiple Influences of Mechanical Forces on Cell Competition. Curr Biol 2019; 29:R762-R774. [DOI: 10.1016/j.cub.2019.06.030] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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20
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Extracellular matrix stiffness cues junctional remodeling for 3D tissue elongation. Nat Commun 2019; 10:3339. [PMID: 31350387 PMCID: PMC6659696 DOI: 10.1038/s41467-019-10874-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Accepted: 05/25/2019] [Indexed: 12/12/2022] Open
Abstract
Organs are sculpted by extracellular as well as cell-intrinsic forces, but how collective cell dynamics are orchestrated in response to environmental cues is poorly understood. Here we apply advanced image analysis to reveal extracellular matrix-responsive cell behaviors that drive elongation of the Drosophila follicle, a model system in which basement membrane stiffness instructs three-dimensional tissue morphogenesis. Through in toto morphometric analyses of wild type and round egg mutants, we find that neither changes in average cell shape nor oriented cell division are required for appropriate organ shape. Instead, a major element is the reorientation of elongated cells at the follicle anterior. Polarized reorientation is regulated by mechanical cues from the basement membrane, which are transduced by the Src tyrosine kinase to alter junctional E-cadherin trafficking. This mechanosensitive cellular behavior represents a conserved mechanism that can elongate edgeless tubular epithelia in a process distinct from those that elongate bounded, planar epithelia. The extracellular matrix can shape developing organs, but how external forces direct intercellular morphogenesis is unclear. Here, the authors use 3D imaging to show that elongation of the Drosophila egg chamber involves polarized cell reorientation signalled by changes in stiffness of the surrounding extracellular matrix.
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21
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Uechi H, Kuranaga E. The Tricellular Junction Protein Sidekick Regulates Vertex Dynamics to Promote Bicellular Junction Extension. Dev Cell 2019; 50:327-338.e5. [PMID: 31353316 DOI: 10.1016/j.devcel.2019.06.017] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 03/20/2019] [Accepted: 06/22/2019] [Indexed: 01/23/2023]
Abstract
Remodeling of cell-cell junctions drives cell intercalation that causes tissue movement during morphogenesis through the shortening and growth of bicellular junctions. The growth of new junctions is essential for continuing and then completing cellular dynamics and tissue shape sculpting; however, the mechanism underlying junction growth remains obscure. We investigated Drosophila genitalia rotation where continuous cell intercalation occurs to show that myosin II accumulating at the vertices of a new junction is required for the junction growth. This myosin II accumulation requires the adhesive transmembrane protein Sidekick (Sdk), which localizes to the adherens junctions (AJs) of tricellular contacts (tAJs). Sdk also localizes to and blocks the accumulation of E-Cadherin at newly formed growing junctions, which maintains the growth rate. We propose that Sdk facilitates tAJ movement by mediating myosin II-driven contraction and altering the adhesive properties at the tAJs, leading to cell-cell junction extension during persistent junction remodeling.
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Affiliation(s)
- Hiroyuki Uechi
- Laboratory for Histogenetic Dynamics, Graduate School of Life Sciences, Tohoku University, 6-3 Aramaki Aza-Aoba, Aoba-ku, Sendai 980-8578, Japan
| | - Erina Kuranaga
- Laboratory for Histogenetic Dynamics, Graduate School of Life Sciences, Tohoku University, 6-3 Aramaki Aza-Aoba, Aoba-ku, Sendai 980-8578, Japan.
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22
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Biocompatible Cantilevers for Mechanical Characterization of Zebrafish Embryos using Image Analysis. SENSORS 2019; 19:s19071506. [PMID: 30925721 PMCID: PMC6479902 DOI: 10.3390/s19071506] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 03/15/2019] [Accepted: 03/22/2019] [Indexed: 12/13/2022]
Abstract
We have developed a force sensing system to continuously evaluate the mechanical elasticity of micrometer-scale (a few hundred micrometers to a millimeter) live tissues. The sensing is achieved by measuring the deflection of force sensitive cantilevers through microscopic image analysis, which does not require electrical strain gauges. Cantilevers made of biocompatible polydimethylsiloxane (PDMS) were actuated by a piezoelectric actuator and functioned as a pair of chopsticks to measure the stiffness of the specimen. The dimensions of the cantilevers were easily adjusted to match the size, range, and stiffness of the zebrafish samples. In this paper, we demonstrated the versatility of this technique by measuring the mechanical elasticity of zebrafish embryos at different stages of development. The stiffness of zebrafish embryos was measured once per hour for 9 h. From the experimental results, we successfully quantified the stiffness change of zebrafish embryos during embryonic development.
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Epithelial Viscoelasticity Is Regulated by Mechanosensitive E-cadherin Turnover. Curr Biol 2019; 29:578-591.e5. [PMID: 30744966 DOI: 10.1016/j.cub.2019.01.021] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 11/14/2018] [Accepted: 01/09/2019] [Indexed: 11/24/2022]
Abstract
Studying how epithelia respond to mechanical stresses is key to understanding tissue shape changes during morphogenesis. Here, we study the viscoelastic properties of the Drosophila wing epithelium during pupal morphogenesis by quantifying mechanical stress and cell shape as a function of time. We find a delay of 8 h between maximal tissue stress and maximal cell elongation, indicating a viscoelastic deformation of the tissue. We show that this viscoelastic behavior emerges from the mechanosensitivity of endocytic E-cadherin turnover. The increase in E-cadherin turnover in response to stress is mediated by mechanosensitive relocalization of the E-cadherin binding protein p120-catenin (p120) from cell junctions to cytoplasm. Mechanosensitivity of E-cadherin turnover is lost in p120 mutant wings, where E-cadherin turnover is constitutively high. In this mutant, the relationship between mechanical stress and stress-dependent cell dynamics is altered. Cells in p120 mutant deform and undergo cell rearrangements oriented along the stress axis more rapidly in response to mechanical stress. These changes imply a lower viscosity of wing epithelium. Taken together, our findings reveal that p120-dependent mechanosensitive E-cadherin turnover regulates viscoelastic behavior of epithelial tissues.
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Bosveld F, Wang Z, Bellaïche Y. Tricellular junctions: a hot corner of epithelial biology. Curr Opin Cell Biol 2018; 54:80-88. [DOI: 10.1016/j.ceb.2018.05.002] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 04/09/2018] [Accepted: 05/08/2018] [Indexed: 02/07/2023]
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25
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AIP1 and cofilin ensure a resistance to tissue tension and promote directional cell rearrangement. Nat Commun 2018; 9:3295. [PMID: 30202062 PMCID: PMC6131156 DOI: 10.1038/s41467-018-05605-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 07/14/2018] [Indexed: 01/30/2023] Open
Abstract
In order to understand how tissue mechanics shapes animal body, it is critical to clarify how cells respond to and resist tissue stress when undergoing morphogenetic processes, such as cell rearrangement. Here, we address the question in the Drosophila wing epithelium, where anisotropic tissue tension orients cell rearrangements. We found that anisotropic tissue tension localizes actin interacting protein 1 (AIP1), a cofactor of cofilin, on the remodeling junction via cooperative binding of cofilin to F-actin. AIP1 and cofilin promote actin turnover and locally regulate the Canoe-mediated linkage between actomyosin and the junction. This mechanism is essential for cells to resist the mechanical load imposed on the remodeling junction perpendicular to the direction of tissue stretching. Thus, the present study delineates how AIP1 and cofilin achieve an optimal balance between resistance to tissue tension and morphogenesis.
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26
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Huebner RJ, Wallingford JB. Coming to Consensus: A Unifying Model Emerges for Convergent Extension. Dev Cell 2018; 46:389-396. [PMID: 30130529 PMCID: PMC6140352 DOI: 10.1016/j.devcel.2018.08.003] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 08/01/2018] [Accepted: 08/01/2018] [Indexed: 12/31/2022]
Abstract
Cell motility is a widespread biological property that is best understood in the context of individual cell migration. Indeed, studies of migration in culture have provided tremendous insight into the signals and mechanics involved and have laid the foundation for our understanding of similar migrations by larger cellular collectives. By contrast, our understanding of another flavor of movement, cell intercalation during convergent extension, is only now emerging. Here, we integrate divergent findings related to intercalation in different settings into a unifying model, paying attention to how this model does and does not resemble current models for directed cell migration.
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Affiliation(s)
- Robert J Huebner
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA
| | - John B Wallingford
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA.
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27
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Herrera-Perez RM, Kasza KE. Biophysical control of the cell rearrangements and cell shape changes that build epithelial tissues. Curr Opin Genet Dev 2018; 51:88-95. [DOI: 10.1016/j.gde.2018.07.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 06/22/2018] [Accepted: 07/16/2018] [Indexed: 11/26/2022]
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28
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Tsuboi A, Ohsawa S, Umetsu D, Sando Y, Kuranaga E, Igaki T, Fujimoto K. Competition for Space Is Controlled by Apoptosis-Induced Change of Local Epithelial Topology. Curr Biol 2018; 28:2115-2128.e5. [DOI: 10.1016/j.cub.2018.05.029] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 04/09/2018] [Accepted: 05/11/2018] [Indexed: 10/14/2022]
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29
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Graner F, Riveline D. 'The Forms of Tissues, or Cell-aggregates': D'Arcy Thompson's influence and its limits. Development 2017; 144:4226-4237. [PMID: 29183936 DOI: 10.1242/dev.151233] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In two chapters of his book On Growth and Form, D'Arcy Thompson used numerous biological and physical observations to show how principles from mathematics and physics - such as pressure differences, surface tension and viscosity - could explain cell shapes and packing within tissues. In this Review, we depict influences that enabled the genesis of his ideas, report examples of his visionary observations and trace his impact over the past 100 years. Recently, his ideas have been revisited as a new field of research emerged, linking cell-level physics with epithelial tissue structure and development. We critically discuss the potential and the limitations of both Thompson's and the modern approaches.
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Affiliation(s)
- François Graner
- Laboratoire Matière et Systèmes Complexes, Université Denis Diderot - Paris 7, CNRS UMR 7057, 75205 Paris Cedex 13, France
| | - Daniel Riveline
- Laboratory of Cell Physics ISIS/IGBMC, CNRS and University of Strasbourg, 67000 Strasbourg, France .,Institut de Génétique et de Biologie Moléculaire et Cellulaire, 67404 Illkirch, France.,Centre National de la Recherche Scientifique, UMR7104, 67404 Illkirch, France.,Institut National de la Santé et de la Recherche Médicale, U964, 67404 Illkirch, France.,Physics Department, Université de Strasbourg, 67000 Strasbourg, France
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