1
|
Hertaeg MJ, Fielding SM, Bi D. Discontinuous Shear Thickening in Biological Tissue Rheology. PHYSICAL REVIEW. X 2024; 14:011027. [PMID: 38994232 PMCID: PMC11238743 DOI: 10.1103/physrevx.14.011027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 07/13/2024]
Abstract
During embryonic morphogenesis, tissues undergo dramatic deformations in order to form functional organs. Similarly, in adult animals, living cells and tissues are continually subjected to forces and deformations. Therefore, the success of embryonic development and the proper maintenance of physiological functions rely on the ability of cells to withstand mechanical stresses as well as their ability to flow in a collective manner. During these events, mechanical perturbations can originate from active processes at the single-cell level, competing with external stresses exerted by surrounding tissues and organs. However, the study of tissue mechanics has been somewhat limited to either the response to external forces or to intrinsic ones. In this work, we use an active vertex model of a 2D confluent tissue to study the interplay of external deformations that are applied globally to a tissue with internal active stresses that arise locally at the cellular level due to cell motility. We elucidate, in particular, the way in which this interplay between globally external and locally internal active driving determines the emergent mechanical properties of the tissue as a whole. For a tissue in the vicinity of a solid-fluid jamming or unjamming transition, we uncover a host of fascinating rheological phenomena, including yielding, shear thinning, continuous shear thickening, and discontinuous shear thickening. These model predictions provide a framework for understanding the recently observed nonlinear rheological behaviors in vivo.
Collapse
Affiliation(s)
- Michael J Hertaeg
- Department of Physics, Durham University, Science Laboratories, South Road, Durham DH1 3LE, United Kingdom
| | - Suzanne M Fielding
- Department of Physics, Durham University, Science Laboratories, South Road, Durham DH1 3LE, United Kingdom
| | - Dapeng Bi
- Department of Physics, Northeastern University, Massachusetts 02115, USA
| |
Collapse
|
2
|
Gou J, Zhang T, Othmer HG. The Interaction of Mechanics and the Hippo Pathway in Drosophila melanogaster. Cancers (Basel) 2023; 15:4840. [PMID: 37835534 PMCID: PMC10571775 DOI: 10.3390/cancers15194840] [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: 08/17/2023] [Revised: 09/10/2023] [Accepted: 09/15/2023] [Indexed: 10/15/2023] Open
Abstract
Drosophila melanogaster has emerged as an ideal system for studying the networks that control tissue development and homeostasis and, given the similarity of the pathways involved, controlled and uncontrolled growth in mammalian systems. The signaling pathways used in patterning the Drosophila wing disc are well known and result in the emergence of interaction of these pathways with the Hippo signaling pathway, which plays a central role in controlling cell proliferation and apoptosis. Mechanical effects are another major factor in the control of growth, but far less is known about how they exert their control. Herein, we develop a mathematical model that integrates the mechanical interactions between cells, which occur via adherens and tight junctions, with the intracellular actin network and the Hippo pathway so as to better understand cell-autonomous and non-autonomous control of growth in response to mechanical forces.
Collapse
Affiliation(s)
- Jia Gou
- Department of Mathematics, University of California, Riverside, CA 92507, USA;
| | - Tianhao Zhang
- School of Mathematics, University of Minnesota, Minneapolis, MN 55455, USA;
| | - Hans G. Othmer
- School of Mathematics, University of Minnesota, Minneapolis, MN 55455, USA;
| |
Collapse
|
3
|
Yamaguchi N, Knaut H. Focal adhesion-mediated cell anchoring and migration: from in vitro to in vivo. Development 2022; 149:275460. [PMID: 35587444 DOI: 10.1242/dev.200647] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Cell-extracellular matrix interactions have been studied extensively using cells cultured in vitro. These studies indicate that focal adhesion (FA)-based cell-extracellular matrix interactions are essential for cell anchoring and cell migration. Whether FAs play a similarly important role in vivo is less clear. Here, we summarize the formation and function of FAs in cultured cells and review how FAs transmit and sense force in vitro. Using examples from animal studies, we also describe the role of FAs in cell anchoring during morphogenetic movements and cell migration in vivo. Finally, we conclude by discussing similarities and differences in how FAs function in vitro and in vivo.
Collapse
Affiliation(s)
- Naoya Yamaguchi
- Skirball Institute of Biomolecular Medicine, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Holger Knaut
- Skirball Institute of Biomolecular Medicine, New York University Grossman School of Medicine, New York, NY 10016, USA
| |
Collapse
|
4
|
Moore RP, Fogerson SM, Tulu US, Yu JW, Cox AH, Sican MA, Li D, Legant WR, Weigel AV, Crawford JM, Betzig E, Kiehart DP. Super-resolution microscopy reveals actomyosin dynamics in medioapical arrays. Mol Biol Cell 2022; 33:ar94. [PMID: 35544300 DOI: 10.1091/mbc.e21-11-0537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Arrays of actin filaments (F-actin) near the apical surface of epithelial cells (medioapical arrays) contribute to apical constriction and morphogenesis throughout phylogeny. Here, super-resolution approaches (grazing incidence structured illumination, GI-SIM and lattice light sheet, LLSM) microscopy resolve individual, fluorescently labeled F-actin and bipolar myosin filaments that drive amnioserosa cell shape changes during dorsal closure in Drosophila. In expanded cells, F-actin and myosin form loose, apically domed meshworks at the plasma membrane. The arrays condense as cells contract, drawing the domes into the plane of the junctional belts. As condensation continues, individual filaments are no longer uniformly apparent. As cells expand, arrays of actomyosin are again resolved - some F-actin turnover likely occurs, but a large fraction of existing filaments rearrange. In morphologically isotropic cells, actin filaments are randomly oriented and during contraction, are drawn together but remain essentially randomly oriented. In anisotropic cells, largely parallel actin filaments are drawn closer to one another. Our images offer unparalleled resolution of F-actin in embryonic tissue show that medioapical arrays are tightly apposed to the plasma membrane, are continuous with meshworks of lamellar F-actin and thereby constitute modified cell cortex. In concert with other tagged array components, super-resolution imaging of live specimens will offer new understanding of cortical architecture and function. [Media: see text] [Media: see text] [Media: see text] [Media: see text] [Media: see text] [Media: see text] [Media: see text] [Media: see text] [Media: see text] [Media: see text].
Collapse
Affiliation(s)
- Regan P Moore
- Biology Department, Duke University, Durham, NC, 27708, USA.,Department of Pharmacology, University of North Carolina, Chapel Hill, NC, 27599, USA.,Joint Department of Biomedical Engineering, University of North Carolina, Chapel Hill, 27599, USA and North Carolina State University, Raleigh, NC, 27695, USA
| | | | - U Serdar Tulu
- Biology Department, Duke University, Durham, NC, 27708, USA
| | - Jason W Yu
- Biology Department, Duke University, Durham, NC, 27708, USA
| | - Amanda H Cox
- Biology Department, Duke University, Durham, NC, 27708, USA
| | | | - Dong Li
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Wesley R Legant
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC, 27599, USA.,Joint Department of Biomedical Engineering, University of North Carolina, Chapel Hill, 27599, USA and North Carolina State University, Raleigh, NC, 27695, USA
| | - Aubrey V Weigel
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, 20147, USA
| | | | - Eric Betzig
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, 20147, USA.,Departments of Physics and Molecular and Cell Biology, University of California, Berkeley, CA, 94720, USA
| | | |
Collapse
|
5
|
Smit HJ, Strong P. Structural Elements of the Biomechanical System of Soft Tissue. Cureus 2020; 12:e7895. [PMID: 32368430 PMCID: PMC7193180 DOI: 10.7759/cureus.7895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
In living organisms, forces are constantly generated and transmitted throughout tissue. Such forces are generated through interaction with the environment and as a result of the body’s endogenous movement. If these internally or externally originating forces exceed the ability of tissues to cope with the applied forces, (i.e. “tissue thresholds”), they will cause force-related tissue harm. However, biotensegrity systems act to prevent these forces from causing structural damage to cells and tissues. The mechanism and structure of soft tissues that enable them to maintain their integrity and prevent damage under constantly changing forces is still not fully understood. The current anatomical and physical knowledge is insufficient to assess and predict how, why, where, and when to expect force-related tissue harm. When including the concept of tensegrity and the related principles of the hierarchical organisation of the elements of the subcellular tensional homeostatic structure into current biomechanical concepts, it increases our understanding of the events in force handling in relation to the onset of force-related tissue harm: Reducing incident forces in tissue to a level that is not harmful to the involved structures is achieved by dissipation, transduction and transferring the force in multiple dimensions. To enable this, the biomechanical systems must function in a continuous and consistent way from the cellular level to the entire body to prevent local peak forces from causing harm. In this article, we explore the biomechanical system with a focus on biotensegrity concepts across several organisational levels, describing in detail how it may function and reflecting on how this might be applied to patient management.
Collapse
Affiliation(s)
- Harm Jaap Smit
- Molecular Biology, Independent Researcher, Amersfoort, NLD
| | - Phil Strong
- Independent Researcher, Oldbury-on-Severn, GBR
| |
Collapse
|
6
|
Pulido Companys P, Norris A, Bischoff M. Coordination of cytoskeletal dynamics and cell behaviour during Drosophila abdominal morphogenesis. J Cell Sci 2020; 133:jcs235325. [PMID: 32229579 PMCID: PMC7132776 DOI: 10.1242/jcs.235325] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 01/20/2020] [Indexed: 12/20/2022] Open
Abstract
During morphogenesis, cells exhibit various behaviours, such as migration and constriction, which need to be coordinated. How this is achieved remains elusive. During morphogenesis of the Drosophila adult abdominal epidermis, larval epithelial cells (LECs) migrate directedly before constricting apically and undergoing apoptosis. Here, we study the mechanisms underlying the transition from migration to constriction. We show that LECs possess a pulsatile apical actomyosin network, and that a change in network polarity correlates with behavioural change. Exploring the properties of the contractile network, we find that cell contractility, as determined by myosin activity, has an impact on the behaviour of the network, as well as on cytoskeletal architecture and cell behaviour. Pulsed contractions occur only in cells with intermediate levels of contractility. Furthermore, increasing levels of the small Rho GTPase Rho1 disrupts pulsing, leading to cells that cycle between two states, characterised by a junctional cortical and an apicomedial actin network. Our results highlight that behavioural change relies on tightly controlled cellular contractility. Moreover, we show that constriction can occur without pulsing, raising questions why constricting cells pulse in some contexts but not in others.
Collapse
Affiliation(s)
- Pau Pulido Companys
- Biomedical Sciences Research Complex, University of St Andrews, North Haugh, St Andrews KY16 9ST, UK
| | - Anneliese Norris
- Biomedical Sciences Research Complex, University of St Andrews, North Haugh, St Andrews KY16 9ST, UK
| | - Marcus Bischoff
- Biomedical Sciences Research Complex, University of St Andrews, North Haugh, St Andrews KY16 9ST, UK
| |
Collapse
|
7
|
Letizia A, He D, Astigarraga S, Colombelli J, Hatini V, Llimargas M, Treisman JE. Sidekick Is a Key Component of Tricellular Adherens Junctions that Acts to Resolve Cell Rearrangements. Dev Cell 2019; 50:313-326.e5. [PMID: 31353315 DOI: 10.1016/j.devcel.2019.07.007] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 05/03/2019] [Accepted: 07/02/2019] [Indexed: 11/27/2022]
Abstract
Tricellular adherens junctions are points of high tension that are central to the rearrangement of epithelial cells. However, the molecular composition of these junctions is unknown, making it difficult to assess their role in morphogenesis. Here, we show that Sidekick, an immunoglobulin family cell adhesion protein, is highly enriched at tricellular adherens junctions in Drosophila. This localization is modulated by tension, and Sidekick is itself necessary to maintain normal levels of cell bond tension. Loss of Sidekick causes defects in cell and junctional rearrangements in actively remodeling epithelial tissues like the retina and tracheal system. The adaptor proteins Polychaetoid and Canoe are enriched at tricellular adherens junctions in a Sidekick-dependent manner; Sidekick functionally interacts with both proteins and directly binds to Polychaetoid. We suggest that Polychaetoid and Canoe link Sidekick to the actin cytoskeleton to enable tricellular adherens junctions to maintain or transmit cell bond tension during epithelial cell rearrangements.
Collapse
Affiliation(s)
- Annalisa Letizia
- Institut de Biologia Molecular de Barcelona, CSIC, Parc Científic de Barcelona, Baldiri Reixac, 10-12, Barcelona 08028, Spain
| | - DanQing He
- Kimmel Center for Biology and Medicine at the Skirball Institute and Department of Cell Biology, NYU School of Medicine, 540 First Avenue, New York, NY 10016, USA
| | - Sergio Astigarraga
- Kimmel Center for Biology and Medicine at the Skirball Institute and Department of Cell Biology, NYU School of Medicine, 540 First Avenue, New York, NY 10016, USA
| | - Julien Colombelli
- Institute for Research in Biomedicine, The Barcelona Institute of Science and Technology, Parc Científic de Barcelona, Baldiri Reixac, 10, Barcelona 08028, Spain
| | - Victor Hatini
- Department of Developmental, Molecular & Chemical Biology, Program in Cell, Molecular and Developmental Biology and Program in Genetics, Tufts University School of Medicine, 150 Harrison Avenue, Jaharis 322, Boston, MA 02111, USA
| | - Marta Llimargas
- Institut de Biologia Molecular de Barcelona, CSIC, Parc Científic de Barcelona, Baldiri Reixac, 10-12, Barcelona 08028, Spain.
| | - Jessica E Treisman
- Kimmel Center for Biology and Medicine at the Skirball Institute and Department of Cell Biology, NYU School of Medicine, 540 First Avenue, New York, NY 10016, USA.
| |
Collapse
|
8
|
McCleery WT, Veldhuis J, Bennett ME, Lynch HE, Ma X, Brodland GW, Hutson MS. Elongated Cells Drive Morphogenesis in a Surface-Wrapped Finite-Element Model of Germband Retraction. Biophys J 2019; 117:157-169. [PMID: 31229244 DOI: 10.1016/j.bpj.2019.05.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 05/13/2019] [Accepted: 05/20/2019] [Indexed: 10/26/2022] Open
Abstract
During Drosophila embryogenesis, the germband first extends to curl around the posterior end of the embryo and then retracts back; however, retraction is not simply the reversal of extension. At a tissue level, extension is coincident with ventral furrow formation, and at a cellular level, extension occurs via convergent cell neighbor exchanges in the germband, whereas retraction involves only changes in cell shape. To understand how cell shapes, tissue organization, and cellular forces drive germband retraction, we investigate this process using a whole-embryo, surface-wrapped cellular finite-element model. This model represents two key epithelial tissues-amnioserosa and germband-as adjacent sheets of two-dimensional cellular finite elements that are wrapped around an ellipsoidal three-dimensional approximation of an embryo. The model reproduces the detailed kinematics of in vivo retraction by fitting just one free model parameter, the tension along germband cell interfaces; all other cellular forces are constrained to follow ratios inferred from experimental observations. With no additional parameter adjustments, the model also reproduces quantitative assessments of mechanical stress using laser dissection and failures of retraction when amnioserosa cells are removed via mutations or microsurgery. Surprisingly, retraction in the model is robust to changes in cellular force values but is critically dependent on starting from a configuration with highly elongated amnioserosa cells. Their extreme cellular elongation is established during the prior process of germband extension and is then used to drive retraction. The amnioserosa is the one tissue whose cellular morphogenesis is reversed from germband extension to retraction, and this reversal coordinates the forces needed to retract the germband back to its pre-extension position and shape. In this case, cellular force strengths are less important than the carefully established cell shapes that direct them. VIDEO ABSTRACT.
Collapse
Affiliation(s)
- W Tyler McCleery
- Department of Physics & Astronomy, Vanderbilt University, Nashville, Tennessee
| | - Jim Veldhuis
- Department of Civil & Environmental Engineering, University of Waterloo, Waterloo, Ontario, Canada
| | - Monica E Bennett
- Department of Physics & Astronomy, Vanderbilt University, Nashville, Tennessee
| | - Holley E Lynch
- Department of Physics, Stetson University, DeLand, Florida
| | - Xiaoyan Ma
- Department of Physics & Astronomy, Vanderbilt University, Nashville, Tennessee
| | - G Wayne Brodland
- Department of Civil & Environmental Engineering, University of Waterloo, Waterloo, Ontario, Canada
| | - M Shane Hutson
- Department of Physics & Astronomy, Vanderbilt University, Nashville, Tennessee; Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee.
| |
Collapse
|
9
|
Blanchard GB, Étienne J, Gorfinkiel N. From pulsatile apicomedial contractility to effective epithelial mechanics. Curr Opin Genet Dev 2018; 51:78-87. [DOI: 10.1016/j.gde.2018.07.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 06/25/2018] [Accepted: 07/16/2018] [Indexed: 10/28/2022]
|
10
|
Lo WC, Madrak C, Kiehart DP, Edwards GS. Unified biophysical mechanism for cell-shape oscillations and cell ingression. Phys Rev E 2018; 97:062414. [PMID: 30011599 PMCID: PMC6440536 DOI: 10.1103/physreve.97.062414] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Indexed: 12/31/2022]
Abstract
We describe a mechanochemical and percolation cascade that augments myosin's regulatory network to tune cytoskeletal forces. Actomyosin forces collectively generate cytoskeletal forces during cell oscillations and ingression, which we quantify by elastic percolation of the internally driven, cross-linked actin network. Contractile units can produce relatively large, oscillatory forces that disrupt crosslinks to reduce cytoskeletal forces. A (reverse) Hopf bifurcation switches contractile units to produce smaller, steady forces that enhance crosslinking and consequently boost cytoskeletal forces to promote ingression. We describe cell-shape changes and cell ingression in terms of intercellular force imbalances along common cell junctions.
Collapse
Affiliation(s)
- Wei-Chang Lo
- Physics Department, Duke University, Durham, North Carolina 27708, USA
| | - Craig Madrak
- Physics Department, Duke University, Durham, North Carolina 27708, USA
| | - Daniel P Kiehart
- Biology Department, Duke University, Durham, North Carolina 27708, USA
| | - Glenn S Edwards
- Physics Department, Duke University, Durham, North Carolina 27708, USA
| |
Collapse
|
11
|
Kiehart DP, Crawford JM, Aristotelous A, Venakides S, Edwards GS. Cell Sheet Morphogenesis: Dorsal Closure in Drosophila melanogaster as a Model System. Annu Rev Cell Dev Biol 2018; 33:169-202. [PMID: 28992442 DOI: 10.1146/annurev-cellbio-111315-125357] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Dorsal closure is a key process during Drosophila morphogenesis that models cell sheet movements in chordates, including neural tube closure, palate formation, and wound healing. Closure occurs midway through embryogenesis and entails circumferential elongation of lateral epidermal cell sheets that close a dorsal hole filled with amnioserosa cells. Signaling pathways regulate the function of cellular structures and processes, including Actomyosin and microtubule cytoskeletons, cell-cell/cell-matrix adhesion complexes, and endocytosis/vesicle trafficking. These orchestrate complex shape changes and movements that entail interactions between five distinct cell types. Genetic and laser perturbation studies establish that closure is robust, resilient, and the consequence of redundancy that contributes to four distinct biophysical processes: contraction of the amnioserosa, contraction of supracellular Actomyosin cables, elongation (stretching?) of the lateral epidermis, and zipping together of two converging cell sheets. What triggers closure and what the emergent properties are that give rise to its extraordinary resilience and fidelity remain key, extant questions.
Collapse
Affiliation(s)
- Daniel P Kiehart
- Department of Biology, Duke University, Durham, North Carolina 27708;
| | - Janice M Crawford
- Department of Biology, Duke University, Durham, North Carolina 27708;
| | - Andreas Aristotelous
- Department of Mathematics, West Chester University, West Chester, Pennsylvania 19383
| | | | - Glenn S Edwards
- Physics Department, Duke University, Durham, North Carolina 27708
| |
Collapse
|
12
|
Blanchard GB. Taking the strain: quantifying the contributions of all cell behaviours to changes in epithelial shape. Philos Trans R Soc Lond B Biol Sci 2017; 372:rstb.2015.0513. [PMID: 28348250 DOI: 10.1098/rstb.2015.0513] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/05/2016] [Indexed: 11/12/2022] Open
Abstract
Computer-assisted tracking of the shapes of many cells over long periods of development has driven the exploration of novel ways to quantify the contributions of different cell behaviours to morphogenesis. A handful of similar methods have now been published that are used to calculate tissue deformations (strain rates) in epithelia. These methods are further used to quantify strain rates attributable to each of the cell behaviours in the tissue, such as cell shape change, cell rearrangement and cell division, that together sum to the tissue strain rates. In this review, aimed at developmental biologists, I will introduce the general approach, characterize differences in current approaches and highlight extensions of these methods that remain to be fully explored. The methods will make a major contribution to the emerging field of tissue mechanics. Precisely quantified strain rates are an essential first step towards exploring constitutive equations relating stress to strain via tissue mechanical properties.This article is part of the themed issue 'Systems morphodynamics: understanding the development of tissue hardware'.
Collapse
Affiliation(s)
- Guy B Blanchard
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| |
Collapse
|
13
|
Dureau M, Alessandri A, Bagnerini P, Vincent S. Modeling and Identification of Amnioserosa Cell Mechanical Behavior by Using Mass-Spring Lattices. IEEE/ACM TRANSACTIONS ON COMPUTATIONAL BIOLOGY AND BIOINFORMATICS 2017; 14:1476-1481. [PMID: 27362988 DOI: 10.1109/tcbb.2016.2586063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Various mechanical models of live amnioserosa cells during Drosophila melanogaster's dorsal closure are proposed. Such models account for specific biomechanical oscillating behaviors and depend on a different set of parameters. The identification of the parameters for each of the proposed models is accomplished according to a least-squares approach in such a way to best fit the cellular dynamics extracted from live images. For the purpose of comparison, the resulting models after identification are validated to allow for the selection of the most appropriate description of such a cell dynamics. The proposed methodology is general and it may be applied to other planar biological processes.
Collapse
|
14
|
Svensson CM, Medyukhina A, Belyaev I, Al-Zaben N, Figge MT. Untangling cell tracks: Quantifying cell migration by time lapse image data analysis. Cytometry A 2017; 93:357-370. [DOI: 10.1002/cyto.a.23249] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Carl-Magnus Svensson
- Applied Systems Biology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute (HKI); Jena Germany
| | - Anna Medyukhina
- Applied Systems Biology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute (HKI); Jena Germany
| | - Ivan Belyaev
- Applied Systems Biology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute (HKI); Jena Germany
- Friedrich Schiller University; Jena Germany
| | - Naim Al-Zaben
- Applied Systems Biology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute (HKI); Jena Germany
- Friedrich Schiller University; Jena Germany
| | - Marc Thilo Figge
- Applied Systems Biology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute (HKI); Jena Germany
- Friedrich Schiller University; Jena Germany
| |
Collapse
|
15
|
Ochoa-Espinosa A, Harmansa S, Caussinus E, Affolter M. Myosin II is not required for Drosophila tracheal branch elongation and cell intercalation. Development 2017; 144:2961-2968. [PMID: 28811312 DOI: 10.1242/dev.148940] [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] [Received: 01/06/2017] [Accepted: 07/05/2017] [Indexed: 01/04/2023]
Abstract
The Drosophila tracheal system consists of an interconnected network of monolayered epithelial tubes that ensures oxygen transport in the larval and adult body. During tracheal dorsal branch (DB) development, individual DBs elongate as a cluster of cells, led by tip cells at the front and trailing cells in the rear. Branch elongation is accompanied by extensive cell intercalation and cell lengthening of the trailing stalk cells. Although cell intercalation is governed by Myosin II (MyoII)-dependent forces during tissue elongation in the Drosophila embryo that lead to germ-band extension, it remained unclear whether MyoII plays a similar active role during tracheal branch elongation and intercalation. Here, we have used a nanobody-based approach to selectively knock down MyoII in tracheal cells. Our data show that, despite the depletion of MyoII function, tip cell migration and stalk cell intercalation (SCI) proceed at a normal rate. This confirms a model in which DB elongation and SCI in the trachea occur as a consequence of tip cell migration, which produces the necessary forces for the branching process.
Collapse
Affiliation(s)
| | - Stefan Harmansa
- Biozentrum, University of Basel, Klingelbergstr. 50/70, 4056 Basel, Switzerland
| | - Emmanuel Caussinus
- Institute of Molecular Life Sciences (IMLS), University of Zurich, 8057 Zurich, Switzerland
| | - Markus Affolter
- Biozentrum, University of Basel, Klingelbergstr. 50/70, 4056 Basel, Switzerland
| |
Collapse
|
16
|
Okuda S, Unoki K, Eiraku M, Tsubota KI. Contractile actin belt and mesh structures provide the opposite dependence of epithelial stiffness on the spontaneous curvature of constituent cells. Dev Growth Differ 2017; 59:455-464. [PMID: 28707721 DOI: 10.1111/dgd.12373] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 05/10/2017] [Accepted: 05/14/2017] [Indexed: 12/31/2022]
Abstract
Actomyosin generates contractile forces within cells, which have a crucial role in determining the macroscopic mechanical properties of epithelial tissues. Importantly, actin cytoskeleton, which propagates actomyosin contractile forces, forms several characteristic structures in a 3D intracellular space, such as a circumferential actin belt lining adherence junctions and an actin mesh beneath the apical membrane. However, little is known about how epithelial mechanical property depends on the intracellular contractile structures. We performed computational simulations using a 3D vertex model, and demonstrated the longitudinal tensile test of an epithelial tube, whose inside and outside are defined as the apical and basal surfaces, respectively. As a result, these subcellular structures provide the contrary dependence of epithelial stiffness and fracture force on the spontaneous curvature of constituent cells; the epithelial stiffness increases with increasing the spontaneous curvature in the case of belt, meanwhile it decreases in the case of mesh. This qualitative difference emerges from the different anisotropic deformability of apical cell surfaces; while belt preserves isotropic apical cell shapes, mesh does not. Moreover, the difference in the anisotropic deformability determines the frequency of cell rearrangements, which in turn effectively decrease the tube stiffness. These results illustrate the importance of the intracellular contractile structures, which may be regulated to optimize mechanical functions of individual epithelial tissues.
Collapse
Affiliation(s)
- Satoru Okuda
- Laboratory for in vitro Histogenesis, RIKEN Center for Developmental Biology (CDB), 2-2-3 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan.,PRESTO, Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama, 332-0012, Japan
| | - Katsuyuki Unoki
- Department of Mechanical Engineering, Graduate School of Engineering, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba, 263-8552, Japan
| | - Mototsugu Eiraku
- Laboratory for in vitro Histogenesis, RIKEN Center for Developmental Biology (CDB), 2-2-3 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan
| | - Ken-Ichi Tsubota
- Department of Mechanical Engineering, Graduate School of Engineering, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba, 263-8552, Japan
| |
Collapse
|
17
|
Goodwin K, Ellis SJ, Lostchuck E, Zulueta-Coarasa T, Fernandez-Gonzalez R, Tanentzapf G. Basal Cell-Extracellular Matrix Adhesion Regulates Force Transmission during Tissue Morphogenesis. Dev Cell 2017; 39:611-625. [PMID: 27923121 DOI: 10.1016/j.devcel.2016.11.003] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Revised: 07/21/2016] [Accepted: 11/07/2016] [Indexed: 10/20/2022]
Abstract
Tissue morphogenesis requires force-generating mechanisms to organize cells into complex structures. Although many such mechanisms have been characterized, we know little about how forces are integrated across developing tissues. We provide evidence that integrin-mediated cell-extracellular matrix (ECM) adhesion modulates the transmission of apically generated tension during dorsal closure (DC) in Drosophila. Integrin-containing adhesive structures resembling focal adhesions were identified on the basal surface of the amnioserosa (AS), an extraembryonic epithelium essential for DC. Genetic modulation of integrin-mediated adhesion results in defective DC. Quantitative image analysis and laser ablation experiments reveal that basal cell-ECM adhesions provide resistance to apical cell displacements and force transmission between neighboring cells in the AS. Finally, we provide evidence for integrin-dependent force transmission to the AS substrate. Overall, we find that integrins regulate force transmission within and between cells, thereby playing an essential role in transmitting tension in developing tissues.
Collapse
Affiliation(s)
- Katharine Goodwin
- Department of Cellular and Physiological Sciences, University of British Columbia, Life Sciences Centre, 2350 Health Science Mall, Vancouver, BC V6T 1Z3, Canada
| | - Stephanie J Ellis
- Department of Cellular and Physiological Sciences, University of British Columbia, Life Sciences Centre, 2350 Health Science Mall, Vancouver, BC V6T 1Z3, Canada
| | - Emily Lostchuck
- Department of Cellular and Physiological Sciences, University of British Columbia, Life Sciences Centre, 2350 Health Science Mall, Vancouver, BC V6T 1Z3, Canada
| | - Teresa Zulueta-Coarasa
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada
| | - Rodrigo Fernandez-Gonzalez
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada; Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada; Developmental and Stem Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5S 1X8, Canada
| | - Guy Tanentzapf
- Department of Cellular and Physiological Sciences, University of British Columbia, Life Sciences Centre, 2350 Health Science Mall, Vancouver, BC V6T 1Z3, Canada.
| |
Collapse
|
18
|
Goodwin K, Lostchuck EE, Cramb KML, Zulueta-Coarasa T, Fernandez-Gonzalez R, Tanentzapf G. Cell-cell and cell-extracellular matrix adhesions cooperate to organize actomyosin networks and maintain force transmission during dorsal closure. Mol Biol Cell 2017; 28:1301-1310. [PMID: 28331071 PMCID: PMC5426845 DOI: 10.1091/mbc.e17-01-0033] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 03/15/2017] [Accepted: 03/17/2017] [Indexed: 11/13/2022] Open
Abstract
Cell–extracellular matrix (ECM) and cell–cell adhesion are interdependent during dorsal closure in the fly. Cell–ECM adhesion is required for normal myosin dynamics and organization of both cell–cell adhesions and actin networks during dorsal closure. Loss of cell–cell adhesion affects cell–ECM adhesion and tissue biomechanics. Tissue morphogenesis relies on the coordinated action of actin networks, cell–cell adhesions, and cell–extracellular matrix (ECM) adhesions. Such coordination can be achieved through cross-talk between cell–cell and cell–ECM adhesions. Drosophila dorsal closure (DC), a morphogenetic process in which an extraembryonic tissue called the amnioserosa contracts and ingresses to close a discontinuity in the dorsal epidermis of the embryo, requires both cell–cell and cell–ECM adhesions. However, whether the functions of these two types of adhesions are coordinated during DC is not known. Here we analyzed possible interdependence between cell–cell and cell–ECM adhesions during DC and its effect on the actomyosin network. We find that loss of cell–ECM adhesion results in aberrant distributions of cadherin-mediated adhesions and actin networks in the amnioserosa and subsequent disruption of myosin recruitment and dynamics. Moreover, loss of cell–cell adhesion caused up-regulation of cell–ECM adhesion, leading to reduced cell deformation and force transmission across amnioserosa cells. Our results show how interdependence between cell–cell and cell–ECM adhesions is important in regulating cell behaviors, force generation, and force transmission critical for tissue morphogenesis.
Collapse
Affiliation(s)
- Katharine Goodwin
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Emily E Lostchuck
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Kaitlyn M L Cramb
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Teresa Zulueta-Coarasa
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada.,Ted Rogers Centre for Heart Research, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Rodrigo Fernandez-Gonzalez
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada.,Ted Rogers Centre for Heart Research, University of Toronto, Toronto, ON M5G 1M1, Canada.,Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada.,Developmental and Stem Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5S 1X8, Canada
| | - Guy Tanentzapf
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| |
Collapse
|
19
|
Vasquez CG, Heissler SM, Billington N, Sellers JR, Martin AC. Drosophila non-muscle myosin II motor activity determines the rate of tissue folding. eLife 2016; 5. [PMID: 28035903 PMCID: PMC5201417 DOI: 10.7554/elife.20828] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2016] [Accepted: 12/08/2016] [Indexed: 12/15/2022] Open
Abstract
Non-muscle cell contractility is critical for tissues to adopt shape changes. Although, the non-muscle myosin II holoenzyme (myosin) is a molecular motor that powers contraction of actin cytoskeleton networks, recent studies have questioned the importance of myosin motor activity cell and tissue shape changes. Here, combining the biochemical analysis of enzymatic and motile properties for purified myosin mutants with in vivo measurements of apical constriction for the same mutants, we show that in vivo constriction rate scales with myosin motor activity. We show that so-called phosphomimetic mutants of the Drosophila regulatory light chain (RLC) do not mimic the phosphorylated RLC state in vitro. The defect in the myosin motor activity in these mutants is evident in developing Drosophila embryos where tissue recoil following laser ablation is decreased compared to wild-type tissue. Overall, our data highlights that myosin activity is required for rapid cell contraction and tissue folding in developing Drosophila embryos. DOI:http://dx.doi.org/10.7554/eLife.20828.001
Collapse
Affiliation(s)
- Claudia G Vasquez
- Department of Biology, Massachusetts Institute of Technology, Cambridge, United States
| | - Sarah M Heissler
- Laboratory of Molecular Physiology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, United States
| | - Neil Billington
- Laboratory of Molecular Physiology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, United States
| | - James R Sellers
- Laboratory of Molecular Physiology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, United States
| | - Adam C Martin
- Department of Biology, Massachusetts Institute of Technology, Cambridge, United States
| |
Collapse
|
20
|
Duque J, Gorfinkiel N. Integration of actomyosin contractility with cell-cell adhesion during dorsal closure. Development 2016; 143:4676-4686. [PMID: 27836966 DOI: 10.1242/dev.136127] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 10/27/2016] [Indexed: 02/01/2023]
Abstract
In this work, we combine genetic perturbation, time-lapse imaging and quantitative image analysis to investigate how pulsatile actomyosin contractility drives cell oscillations, apical cell contraction and tissue closure during morphogenesis of the amnioserosa, the main force-generating tissue during the dorsal closure in Drosophila We show that Myosin activity determines the oscillatory and contractile behaviour of amnioserosa cells. Reducing Myosin activity prevents cell shape oscillations and reduces cell contractility. By contrast, increasing Myosin activity increases the amplitude of cell shape oscillations and the time cells spend in the contracted phase relative to the expanded phase during an oscillatory cycle, promoting cell contractility and tissue closure. Furthermore, we show that in AS cells, Rok controls Myosin foci formation and Mbs regulates not only Myosin phosphorylation but also adhesion dynamics through control of Moesin phosphorylation, showing that Mbs coordinates actomyosin contractility with cell-cell adhesion during amnioserosa morphogenesis.
Collapse
Affiliation(s)
- Julia Duque
- Centro de Biología Molecular 'Severo Ochoa', CSIC-UAM, Cantoblanco, Madrid 28049, Spain
| | - Nicole Gorfinkiel
- Centro de Biología Molecular 'Severo Ochoa', CSIC-UAM, Cantoblanco, Madrid 28049, Spain
| |
Collapse
|
21
|
Jurado J, de Navascués J, Gorfinkiel N. α-Catenin stabilises Cadherin-Catenin complexes and modulates actomyosin dynamics to allow pulsatile apical contraction. J Cell Sci 2016; 129:4496-4508. [PMID: 27831494 DOI: 10.1242/jcs.193268] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 11/02/2016] [Indexed: 01/07/2023] Open
Abstract
We have investigated how cell contractility and adhesion are functionally integrated during epithelial morphogenesis. To this end, we have analysed the role of α-Catenin, a key molecule linking E-Cadherin-based adhesion and the actomyosin cytoskeleton, during Drosophila embryonic dorsal closure, by studying a newly developed allelic series. We find that α-Catenin regulates pulsatile apical contraction in the amnioserosa, the main force-generating tissue driving closure of the embryonic epidermis. α-Catenin controls actomyosin dynamics by stabilising and promoting the formation of actomyosin foci, and also stabilises DE-Cadherin (Drosophila E-Cadherin, also known as Shotgun) at the cell membrane, suggesting that medioapical actomyosin contractility regulates junction stability. Furthermore, we uncover a genetic interaction between α-Catenin and Vinculin, and a tension-dependent recruitment of Vinculin to amniosersoa apical cell membranes, suggesting the existence of a mechano-sensitive module operating in this tissue.
Collapse
Affiliation(s)
- Jaime Jurado
- Centro de Biología Molecular "Severo Ochoa", CSIC-UAM, Cantoblanco, Madrid 28049, Spain
| | - Joaquín de Navascués
- European Cancer Stem Cell Research Institute, School of Biosciences, Cardiff University, Cardiff CF24 4HQ, UK
| | - Nicole Gorfinkiel
- Centro de Biología Molecular "Severo Ochoa", CSIC-UAM, Cantoblanco, Madrid 28049, Spain
| |
Collapse
|
22
|
Amnioserosa cell constriction but not epidermal actin cable tension autonomously drives dorsal closure. Nat Cell Biol 2016; 18:1161-1172. [PMID: 27749821 DOI: 10.1038/ncb3420] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 09/08/2016] [Indexed: 12/15/2022]
Abstract
Tissue morphogenesis requires coordination of multiple force-producing components. During dorsal closure in fly embryogenesis, an epidermis opening closes. A tensioned epidermal actin/MyosinII cable, which surrounds the opening, produces a force that is thought to combine with another MyosinII force mediating apical constriction of the amnioserosa cells that fill the opening. A model proposing that each force could autonomously drive dorsal closure was recently challenged by a model in which the two forces combine in a ratchet mechanism. Acute force elimination via selective MyosinII depletion in one or the other tissue shows that the amnioserosa tissue autonomously drives dorsal closure while the actin/MyosinII cable cannot. These findings exclude both previous models, although a contribution of the ratchet mechanism at dorsal closure onset remains likely. This shifts the current view of dorsal closure being a combinatorial force-component system to a single tissue-driven closure event.
Collapse
|
23
|
Lacy ME, Hutson MS. Amnioserosa development and function in Drosophila embryogenesis: Critical mechanical roles for an extraembryonic tissue. Dev Dyn 2016; 245:558-68. [PMID: 26878336 DOI: 10.1002/dvdy.24395] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Revised: 02/08/2016] [Accepted: 02/09/2016] [Indexed: 11/07/2022] Open
Abstract
Despite being a short-lived, extraembryonic tissue, the amnioserosa plays critical roles in the major morphogenetic events of Drosophila embryogenesis. These roles involve both cellular mechanics and biochemical signaling. Its best-known role is in dorsal closure-well studied by both developmental biologists and biophysicists-but the amnioserosa is also important during earlier developmental stages. Here, we provide an overview of amnioserosa specification and its role in several key developmental stages: germ band extension, germ band retraction, and dorsal closure. We also compare embryonic development in Drosophila and its relative Megaselia to highlight how the amnioserosa and its roles have evolved. Placed in context, the amnioserosa provides a fascinating example of how signaling, mechanics, and morphogen patterns govern cell-type specification and subsequent morphogenetic changes in cell shape, orientation, and movement. Developmental Dynamics 245:558-568, 2016. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Monica E Lacy
- Department of Physics & Astronomy, Vanderbilt University, Nashville, Tennessee
| | - M Shane Hutson
- Department of Physics & Astronomy, Vanderbilt University, Nashville, Tennessee.,Vanderbilt Institute for Integrative Biosystems Research & Education, Vanderbilt University, Nashville, Tennessee
| |
Collapse
|
24
|
Kannan N, Tang VW. Synaptopodin couples epithelial contractility to α-actinin-4-dependent junction maturation. J Cell Biol 2016; 211:407-34. [PMID: 26504173 PMCID: PMC4621826 DOI: 10.1083/jcb.201412003] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
A novel tension-sensitive junctional protein, synaptopodin, can relay biophysical input from cellular actomyosin contractility to induce biochemical changes at cell–cell contacts, resulting in structural reorganization of the junctional complex and epithelial barrier maturation. The epithelial junction experiences mechanical force exerted by endogenous actomyosin activities and from interactions with neighboring cells. We hypothesize that tension generated at cell–cell adhesive contacts contributes to the maturation and assembly of the junctional complex. To test our hypothesis, we used a hydraulic apparatus that can apply mechanical force to intercellular junction in a confluent monolayer of cells. We found that mechanical force induces α-actinin-4 and actin accumulation at the cell junction in a time- and tension-dependent manner during junction development. Intercellular tension also induces α-actinin-4–dependent recruitment of vinculin to the cell junction. In addition, we have identified a tension-sensitive upstream regulator of α-actinin-4 as synaptopodin. Synaptopodin forms a complex containing α-actinin-4 and β-catenin and interacts with myosin II, indicating that it can physically link adhesion molecules to the cellular contractile apparatus. Synaptopodin depletion prevents junctional accumulation of α-actinin-4, vinculin, and actin. Knockdown of synaptopodin and α-actinin-4 decreases the strength of cell–cell adhesion, reduces the monolayer permeability barrier, and compromises cellular contractility. Our findings underscore the complexity of junction development and implicate a control process via tension-induced sequential incorporation of junctional components.
Collapse
Affiliation(s)
- Nivetha Kannan
- Program in Global Public Health, University of Illinois, Urbana-Champaign, Champaign, IL 61801
| | - Vivian W Tang
- Department of Cell and Developmental Biology, University of Illinois, Urbana-Champaign, Champaign, IL 61801
| |
Collapse
|
25
|
Gorfinkiel N. From actomyosin oscillations to tissue-level deformations. Dev Dyn 2015; 245:268-75. [DOI: 10.1002/dvdy.24363] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Revised: 10/26/2015] [Accepted: 10/26/2015] [Indexed: 12/13/2022] Open
|
26
|
Machado PF, Duque J, Étienne J, Martinez-Arias A, Blanchard GB, Gorfinkiel N. Emergent material properties of developing epithelial tissues. BMC Biol 2015; 13:98. [PMID: 26596771 PMCID: PMC4656187 DOI: 10.1186/s12915-015-0200-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 10/13/2015] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Force generation and the material properties of cells and tissues are central to morphogenesis but remain difficult to measure in vivo. Insight is often limited to the ratios of mechanical properties obtained through disruptive manipulation, and the appropriate models relating stress and strain are unknown. The Drosophila amnioserosa epithelium progressively contracts over 3 hours of dorsal closure, during which cell apices exhibit area fluctuations driven by medial myosin pulses with periods of 1.5-6 min. Linking these two timescales and understanding how pulsatile contractions drive morphogenetic movements is an urgent challenge. RESULTS We present a novel framework to measure in a continuous manner the mechanical properties of epithelial cells in the natural context of a tissue undergoing morphogenesis. We show that the relationship between apicomedial myosin fluorescence intensity and strain during fluctuations is consistent with a linear behaviour, although with a lag. We thus used myosin fluorescence intensity as a proxy for active force generation and treated cells as natural experiments of mechanical response under cyclic loading, revealing unambiguous mechanical properties from the hysteresis loop relating stress to strain. Amnioserosa cells can be described as a contractile viscoelastic fluid. We show that their emergent mechanical behaviour can be described by a linear viscoelastic rheology at timescales relevant for tissue morphogenesis. For the first time, we establish relative changes in separate effective mechanical properties in vivo. Over the course of dorsal closure, the tissue solidifies and effective stiffness doubles as net contraction of the tissue commences. Combining our findings with those from previous laser ablation experiments, we show that both apicomedial and junctional stress also increase over time, with the relative increase in apicomedial stress approximately twice that of other obtained measures. CONCLUSIONS Our results show that in an epithelial tissue undergoing net contraction, stiffness and stress are coupled. Dorsal closure cell apical contraction is driven by the medial region where the relative increase in stress is greater than that of stiffness. At junctions, by contrast, the relative increase in the mechanical properties is the same, so the junctional contribution to tissue deformation is constant over time. An increase in myosin activity is likely to underlie, at least in part, the change in medioapical properties and we suggest that its greater effect on stress relative to stiffness is fundamental to actomyosin systems and confers on tissues the ability to regulate contraction rates in response to changes in external mechanics.
Collapse
Affiliation(s)
- Pedro F Machado
- Department of Genetics, University of Cambridge, Downing Street, Cambridge, CB2 3EH, UK
| | - Julia Duque
- Centro de Biología Molecular Severo Ochoa, CSIC, C/ Nicolás Cabrera 1, Madrid, 28049, Spain
| | - Jocelyn Étienne
- Université Grenoble Alpes, Laboratoire Interdisciplinaire de Physique, BP 53, Cedex 9, Grenoble, 38041, France.,CNRS, Laboratoire Interdisciplinaire de Physique, BP 53, Cedex 9, Grenoble, 38041, France
| | | | - Guy B Blanchard
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge, CB2 3DY, UK.
| | - Nicole Gorfinkiel
- Centro de Biología Molecular Severo Ochoa, CSIC, C/ Nicolás Cabrera 1, Madrid, 28049, Spain.
| |
Collapse
|
27
|
Flores-Benitez D, Knust E. Crumbs is an essential regulator of cytoskeletal dynamics and cell-cell adhesion during dorsal closure in Drosophila. eLife 2015; 4. [PMID: 26544546 PMCID: PMC4718732 DOI: 10.7554/elife.07398] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 11/06/2015] [Indexed: 12/12/2022] Open
Abstract
The evolutionarily conserved Crumbs protein is required for epithelial polarity and morphogenesis. Here we identify a novel role of Crumbs as a negative regulator of actomyosin dynamics during dorsal closure in the Drosophila embryo. Embryos carrying a mutation in the FERM (protein 4.1/ezrin/radixin/moesin) domain-binding motif of Crumbs die due to an overactive actomyosin network associated with disrupted adherens junctions. This phenotype is restricted to the amnioserosa and does not affect other embryonic epithelia. This function of Crumbs requires DMoesin, the Rho1-GTPase, class-I p21-activated kinases and the Arp2/3 complex. Data presented here point to a critical role of Crumbs in regulating actomyosin dynamics, cell junctions and morphogenesis. DOI:http://dx.doi.org/10.7554/eLife.07398.001 A layer of epithelial cells covers the body surface of animals. Epithelial cells have a property known as polarity; this means that they have two different poles, one of which is in contact with the environment. Midway through embryonic development, the Drosophila embryo is covered by two kinds of epithelial sheets; the epidermis on the front, the belly and the sides of the embryo, and the amnioserosa on the back. In the second half of embryonic development, the amnioserosa is brought into the embryo in a process called dorsal closure, while the epidermis expands around the back of the embryo to encompass it. One of the major activities driving dorsal closure is the contraction of amnioserosa cells. This contraction depends on the highly dynamic activity of the protein network that helps give cells their shape, known as the actomyosin cytoskeleton. One major question in the field is how changes in the actomyosin cytoskeleton are controlled as tissues take shape (a process known as “morphogenesis”) and how the integrity of epithelial tissues is maintained during these processes. A key regulator of epidermal and amnioserosa polarity is an evolutionarily conserved protein called Crumbs. The epithelial tissues of mutant embryos that do not produce Crumbs lose polarity and integrity, and the embryos fail to develop properly. Flores-Benitez and Knust have now studied the role of Crumbs in the morphogenesis of the amnioserosa during dorsal closure. This revealed that fly embryos that produce a mutant Crumbs protein that cannot interact with a protein called Moesin (which links the cell membrane and the actomyosin cytoskeleton) are unable to complete dorsal closure. Detailed analyses showed that this failure of dorsal closure is due to the over-activity of the actomyosin cytoskeleton in the amnioserosa. This results in increased and uncoordinated contractions of the cells, and is accompanied by defects in cell-cell adhesion that ultimately cause the amnioserosa to lose integrity. Flores-Benitez and Knust’s genetic analyses further showed that several different signalling systems participate in this process. Flores-Benitez and Knust’s results reveal an unexpected role of Crumbs in coordinating polarity, actomyosin activity and cell-cell adhesion. Further work is now needed to understand the molecular mechanisms and interactions that enable Crumbs to coordinate these processes; in particular, to unravel how Crumbs influences the periodic contractions that drive changes in cell shape. It will also be important to investigate whether Crumbs is involved in similar mechanisms that operate in other developmental events in which actomyosin oscillations have been linked to tissue morphogenesis. DOI:http://dx.doi.org/10.7554/eLife.07398.002
Collapse
Affiliation(s)
| | - Elisabeth Knust
- Max-Planck-Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| |
Collapse
|
28
|
Saias L, Swoger J, D’Angelo A, Hayes P, Colombelli J, Sharpe J, Salbreux G, Solon J. Decrease in Cell Volume Generates Contractile Forces Driving Dorsal Closure. Dev Cell 2015; 33:611-21. [DOI: 10.1016/j.devcel.2015.03.016] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Revised: 08/18/2014] [Accepted: 03/16/2015] [Indexed: 01/06/2023]
|
29
|
Siedlik MJ, Nelson CM. Regulation of tissue morphodynamics: an important role for actomyosin contractility. Curr Opin Genet Dev 2015; 32:80-5. [PMID: 25748251 DOI: 10.1016/j.gde.2015.01.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 01/19/2015] [Accepted: 01/21/2015] [Indexed: 01/13/2023]
Abstract
Forces arising from contractile actomyosin filaments help shape tissue form during morphogenesis. Developmental events that result from actomyosin contractility include tissue elongation, bending, budding, and collective migration. Here, we highlight recent insights into these morphogenetic processes from the perspective of actomyosin contractility as a key regulator. Emphasis is placed on a range of results obtained through live imaging, culture, and computational methods. Combining these approaches in the future has the potential to generate a robust, quantitative understanding of tissue morphodynamics.
Collapse
Affiliation(s)
- Michael J Siedlik
- Department of Chemical & Biological Engineering, Princeton University, Princeton, NJ 08544, United States
| | - Celeste M Nelson
- Department of Chemical & Biological Engineering, Princeton University, Princeton, NJ 08544, United States; Department of Molecular Biology, Princeton University, Princeton, NJ 08544, United States.
| |
Collapse
|
30
|
Vasquez CG, Tworoger M, Martin AC. Dynamic myosin phosphorylation regulates contractile pulses and tissue integrity during epithelial morphogenesis. ACTA ACUST UNITED AC 2014; 206:435-50. [PMID: 25092658 PMCID: PMC4121972 DOI: 10.1083/jcb.201402004] [Citation(s) in RCA: 114] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Apical constriction is a cell shape change that promotes epithelial bending. Activation of nonmuscle myosin II (Myo-II) by kinases such as Rho-associated kinase (Rok) is important to generate contractile force during apical constriction. Cycles of Myo-II assembly and disassembly, or pulses, are associated with apical constriction during Drosophila melanogaster gastrulation. It is not understood whether Myo-II phosphoregulation organizes contractile pulses or whether pulses are important for tissue morphogenesis. Here, we show that Myo-II pulses are associated with pulses of apical Rok. Mutants that mimic Myo-II light chain phosphorylation or depletion of myosin phosphatase inhibit Myo-II contractile pulses, disrupting both actomyosin coalescence into apical foci and cycles of Myo-II assembly/disassembly. Thus, coupling dynamic Myo-II phosphorylation to upstream signals organizes contractile Myo-II pulses in both space and time. Mutants that mimic Myo-II phosphorylation undergo continuous, rather than incremental, apical constriction. These mutants fail to maintain intercellular actomyosin network connections during tissue invagination, suggesting that Myo-II pulses are required for tissue integrity during morphogenesis.
Collapse
Affiliation(s)
- Claudia G Vasquez
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142
| | - Mike Tworoger
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142
| | - Adam C Martin
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142
| |
Collapse
|
31
|
Wells AR, Zou RS, Tulu US, Sokolow AC, Crawford JM, Edwards GS, Kiehart DP. Complete canthi removal reveals that forces from the amnioserosa alone are sufficient to drive dorsal closure in Drosophila. Mol Biol Cell 2014; 25:3552-68. [PMID: 25253724 PMCID: PMC4230616 DOI: 10.1091/mbc.e14-07-1190] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Drosophila's dorsal closure provides an excellent model system with which to analyze biomechanical processes during morphogenesis. During native closure, the amnioserosa, flanked by two lateral epidermal sheets, forms an eye-shaped opening with canthi at each corner. The dynamics of amnioserosa cells and actomyosin purse strings in the leading edges of epidermal cells promote closure, whereas the bulk of the lateral epidermis opposes closure. Canthi maintain purse string curvature (necessary for their dorsalward forces), and zipping at the canthi shortens leading edges, ensuring a continuous epithelium at closure completion. We investigated the requirement for intact canthi during closure with laser dissection approaches. Dissection of one or both canthi resulted in tissue recoil and flattening of each purse string. After recoil and a temporary pause, closure resumed at approximately native rates until slowing near the completion of closure. Thus the amnioserosa alone can drive closure after dissection of one or both canthi, requiring neither substantial purse string curvature nor zipping during the bulk of closure. How the embryo coordinates multiple, large forces (each of which is orders of magnitude greater than the net force) during native closure and is also resilient to multiple perturbations are key extant questions.
Collapse
Affiliation(s)
| | - Roger S Zou
- Department of Biology, Duke University, Durham, NC 27708
| | - U Serdar Tulu
- Department of Biology, Duke University, Durham, NC 27708
| | - Adam C Sokolow
- Department of Physics, Duke University, Durham, NC 27708
| | | | | | | |
Collapse
|
32
|
Spatiotemporal control of epithelial remodeling by regulated myosin phosphorylation. Proc Natl Acad Sci U S A 2014; 111:11732-7. [PMID: 25071215 DOI: 10.1073/pnas.1400520111] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Spatiotemporally regulated actomyosin contractility generates the forces that drive epithelial cell rearrangements and tissue remodeling. Phosphorylation of the myosin II regulatory light chain (RLC) promotes the assembly of myosin monomers into active contractile filaments and is an essential mechanism regulating the level of myosin activity. However, the effects of phosphorylation on myosin localization, dynamics, and function during epithelial remodeling are not well understood. In Drosophila, planar polarized myosin contractility is required for oriented cell rearrangements during elongation of the body axis. We show that regulated myosin phosphorylation influences spatial and temporal properties of contractile behavior at molecular, cellular, and tissue length scales. Expression of myosin RLC variants that prevent or mimic phosphorylation both disrupt axis elongation, but have distinct effects at the molecular and cellular levels. Unphosphorylatable RLC produces fewer, slower cell rearrangements, whereas phosphomimetic RLC accelerates rearrangement and promotes higher-order cell interactions. Quantitative live imaging and biophysical approaches reveal that both phosphovariants reduce myosin planar polarity and mechanical anisotropy, altering the orientation of cell rearrangements during axis elongation. Moreover, the localized myosin activator Rho-kinase is required for spatially regulated myosin activity, even when the requirement for phosphorylation is bypassed by the expression of phosphomimetic myosin RLC. These results indicate that myosin phosphorylation influences both the level and the spatiotemporal regulation of myosin activity, linking molecular properties of myosin activity to tissue morphogenesis.
Collapse
|