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Boutillon A, Banavar SP, Campàs O. Conserved physical mechanisms of cell and tissue elongation. Development 2024; 151:dev202687. [PMID: 38767601 PMCID: PMC11190436 DOI: 10.1242/dev.202687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Living organisms have the ability to self-shape into complex structures appropriate for their function. The genetic and molecular mechanisms that enable cells to do this have been extensively studied in several model and non-model organisms. In contrast, the physical mechanisms that shape cells and tissues have only recently started to emerge, in part thanks to new quantitative in vivo measurements of the physical quantities guiding morphogenesis. These data, combined with indirect inferences of physical characteristics, are starting to reveal similarities in the physical mechanisms underlying morphogenesis across different organisms. Here, we review how physics contributes to shape cells and tissues in a simple, yet ubiquitous, morphogenetic transformation: elongation. Drawing from observed similarities across species, we propose the existence of conserved physical mechanisms of morphogenesis.
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Affiliation(s)
- Arthur Boutillon
- Cluster of Excellence Physics of Life, TU Dresden, 01062 Dresden, Germany
| | - Samhita P. Banavar
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08540, USA
| | - Otger Campàs
- Cluster of Excellence Physics of Life, TU Dresden, 01062 Dresden, Germany
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
- Center for Systems Biology Dresden, 01307 Dresden, Germany
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2
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Rangarajan ES, Smith EW, Izard T. The nematode α-catenin ortholog, HMP1, has an extended α-helix when bound to actin filaments. J Biol Chem 2023; 299:102817. [PMID: 36539037 PMCID: PMC9860117 DOI: 10.1016/j.jbc.2022.102817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 12/09/2022] [Accepted: 12/11/2022] [Indexed: 12/23/2022] Open
Abstract
The regulation of cell-cell junctions during epidermal morphogenesis ensures tissue integrity, a process regulated by α-catenin. This cytoskeletal protein connects the cadherin complex to filamentous actin at cell-cell junctions. The cadherin-catenin complex plays key roles in cell physiology, organism development, and disease. While mutagenesis of Caenorhabditis elegans cadherin and catenin shows that these proteins are key for embryonic morphogenesis, we know surprisingly little about their structure and attachment to the cytoskeleton. In contrast to mammalian α-catenin that functions as a dimer or monomer, the α-catenin ortholog from C. elegans, HMP1 for humpback, is a monomer. Our cryogenic electron microscopy (cryoEM) structure of HMP1/α-catenin reveals that the amino- and carboxy-terminal domains of HMP1/α-catenin are disordered and not in contact with the remaining HMP1/α-catenin middle domain. Since the carboxy-terminal HMP1/α-catenin domain is the F-actin-binding domain (FABD), this interdomain constellation suggests that HMP1/α-catenin is constitutively active, which we confirm biochemically. Our perhaps most surprising finding, given the high sequence similarity between the mammalian and nematode proteins, is our cryoEM structure of HMP1/α-catenin bound to F-actin. Unlike the structure of mammalian α-catenin bound to F-actin, binding to F-actin seems to allosterically convert a loop region of the HMP1/α-catenin FABD to extend an HMP1/α-catenin FABD α-helix. We use cryoEM and bundling assays to show for the first time how the FABD of HMP1/α-catenin bundles actin in the absence of force. Collectively, our data advance our understanding of α-catenin regulation of cell-cell contacts and additionally aid our understanding of the evolution of multicellularity in metazoans.
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Affiliation(s)
| | | | - Tina Izard
- Cell Adhesion Laboratory, UF Scripps, Jupiter, Florida, USA; The Skaggs Graduate School, The Scripps Research Institute, Jupiter, Florida, USA.
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3
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Sanfeliu-Cerdán N, Lin LC, Dunn AR, Goodman MB, Krieg M. Visualizing Neurons Under Tension In Vivo with Optogenetic Molecular Force Sensors. Methods Mol Biol 2023; 2600:239-266. [PMID: 36587102 DOI: 10.1007/978-1-0716-2851-5_16] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The visualization of mechanical stress distribution in specific molecular networks within a living and physiologically active cell or animal remains a formidable challenge in mechanobiology. The advent of fluorescence-resonance energy transfer (FRET)-based molecular tension sensors overcame a significant hurdle that now enables us to address previously technically limited questions. Here, we describe a method that uses genetically encoded FRET tension sensors to visualize the mechanics of cytoskeletal networks in neurons of living animals with sensitized emission FRET and confocal scanning light microscopy. This method uses noninvasive immobilization of living animals to image neuronal β-spectrin cytoskeleton at the diffraction limit, and leverages multiple imaging controls to verify and underline the quality of the measurements. In combination with a semiautomated machine-vision algorithm to identify and trace individual neurites, our analysis performs simultaneous calculation of FRET efficiencies and visualizes statistical uncertainty on a pixel by pixel basis. Our approach is not limited to genetically encoded spectrin tension sensors, but can also be used for any kind of ratiometric imaging in neuronal cells both in vivo and in vitro.
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Affiliation(s)
- Neus Sanfeliu-Cerdán
- Neurophotonics and Mechanical Systems Biology, ICFO, Institut de Ciències Fotòniques, ICFO, Castelldefels, Spain
| | - Li-Chun Lin
- Neurophotonics and Mechanical Systems Biology, ICFO, Institut de Ciències Fotòniques, ICFO, Castelldefels, Spain
| | - Alexander R Dunn
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA
| | - Miriam B Goodman
- Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA
| | - Michael Krieg
- Neurophotonics and Mechanical Systems Biology, ICFO, Institut de Ciències Fotòniques, ICFO, Castelldefels, Spain.
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Serre JM, Lucas B, Martin SCT, Heier JA, Shao X, Hardin J. C. elegans srGAP is an α-catenin M domain-binding protein that strengthens cadherin-dependent adhesion during morphogenesis. Development 2022; 149:dev200775. [PMID: 36125129 PMCID: PMC10655919 DOI: 10.1242/dev.200775] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 08/23/2022] [Indexed: 11/20/2022]
Abstract
The cadherin-catenin complex (CCC) is central to embryonic development and tissue repair, yet how CCC binding partners function alongside core CCC components remains poorly understood. Here, we establish a previously unappreciated role for an evolutionarily conserved protein, the slit-robo GTPase-activating protein SRGP-1/srGAP, in cadherin-dependent morphogenetic processes in the Caenorhabditis elegans embryo. SRGP-1 binds to the M domain of the core CCC component, HMP-1/α-catenin, via its C terminus. The SRGP-1 C terminus is sufficient to target it to adherens junctions, but only during later embryonic morphogenesis, when junctional tension is known to increase. Surprisingly, mutations that disrupt stabilizing salt bridges in the M domain block this recruitment. Loss of SRGP-1 leads to an increase in mobility and decrease of junctional HMP-1. In sensitized genetic backgrounds with weakened adherens junctions, loss of SRGP-1 leads to late embryonic failure. Rescue of these phenotypes requires the C terminus of SRGP-1 but also other domains of the protein. Taken together, these data establish a role for an srGAP in stabilizing and organizing the CCC during epithelial morphogenesis by binding to a partially closed conformation of α-catenin at junctions.
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Affiliation(s)
- Joel M. Serre
- Program in Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Bethany Lucas
- Department of Biology, Regis University, 3333 Regis Blvd., Denver, CO 80221, USA
| | - Sterling C. T. Martin
- Biophysics Graduate Program, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Jonathon A. Heier
- Department of Integrative Biology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Xiangqiang Shao
- Wisconsin State Laboratory of Hygiene, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Jeff Hardin
- Program in Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA
- Biophysics Graduate Program, University of Wisconsin-Madison, Madison, WI 53706, USA
- Department of Integrative Biology, University of Wisconsin-Madison, Madison, WI 53706, USA
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5
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Sutlive J, Xiu H, Chen Y, Gou K, Xiong F, Guo M, Chen Z. Generation, Transmission, and Regulation of Mechanical Forces in Embryonic Morphogenesis. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2103466. [PMID: 34837328 PMCID: PMC8831476 DOI: 10.1002/smll.202103466] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 08/19/2021] [Indexed: 05/02/2023]
Abstract
Embryonic morphogenesis is a biological process which depicts shape forming of tissues and organs during development. Unveiling the roles of mechanical forces generated, transmitted, and regulated in cells and tissues through these processes is key to understanding the biophysical mechanisms governing morphogenesis. To this end, it is imperative to measure, simulate, and predict the regulation and control of these mechanical forces during morphogenesis. This article aims to provide a comprehensive review of the recent advances on mechanical properties of cells and tissues, generation of mechanical forces in cells and tissues, the transmission processes of these generated forces during cells and tissues, the tools and methods used to measure and predict these mechanical forces in vivo, in vitro, or in silico, and to better understand the corresponding regulation and control of generated forces. Understanding the biomechanics and mechanobiology of morphogenesis will not only shed light on the fundamental physical mechanisms underlying these concerted biological processes during normal development, but also uncover new information that will benefit biomedical research in preventing and treating congenital defects or tissue engineering and regeneration.
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Affiliation(s)
- Joseph Sutlive
- Department of Surgery, Brigham and Women’s Hospital/Harvard Medical School, Boston, MA 02115
| | - Haning Xiu
- Department of Surgery, Brigham and Women’s Hospital/Harvard Medical School, Boston, MA 02115
| | - Yunfeng Chen
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA 92037
| | - Kun Gou
- Department of Mathematical, Physical, and Engineering Sciences, Texas A&M University-San Antonio, San Antonio, TX 78224
| | - Fengzhu Xiong
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, UK
| | - Ming Guo
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Zi Chen
- Department of Surgery, Brigham and Women’s Hospital/Harvard Medical School, Boston, MA 02115
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Lehmann C, Pohl C. A Maternal-Effect Toxin Affects Epithelial Differentiation and Tissue Mechanics in Caenorhabditis elegans. Front Cell Dev Biol 2021; 9:743496. [PMID: 34722524 PMCID: PMC8551626 DOI: 10.3389/fcell.2021.743496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Accepted: 09/21/2021] [Indexed: 11/13/2022] Open
Abstract
Selfish genetic elements that act as post-segregation distorters cause lethality in non-carrier individuals after fertilization. Two post-segregation distorters have been previously identified in Caenorhabditis elegans, the peel-1/zeel-1 and the sup-35/pha-1 elements. These elements seem to act as modification-rescue systems, also called toxin/antidote pairs. Here we show that the maternal-effect toxin/zygotic antidote pair sup-35/pha-1 is required for proper expression of apical junction (AJ) components in epithelia and that sup-35 toxicity increases when pathways that establish and maintain basal epithelial characteristics, die-1, elt-1, lin-26, and vab-10, are compromised. We demonstrate that pha-1(e2123) embryos, which lack the antidote, are defective in epidermal morphogenesis and frequently fail to elongate. Moreover, seam cells are frequently misshaped and mispositioned and cell bond tension is reduced in pha-1(e2123) embryos, suggesting altered tissue material properties in the epidermis. Several aspects of this phenotype can also be induced in wild-type embryos by exerting mechanical stress through uniaxial loading. Seam cell shape, tissue mechanics, and elongation can be restored in pha-1(e2123) embryos if expression of the AJ molecule DLG-1/Discs large is reduced. Thus, our experiments suggest that maternal-effect toxicity disrupts proper development of the epidermis which involves distinct transcriptional regulators and AJ components.
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Affiliation(s)
- Christina Lehmann
- Buchmann Institute for Molecular Life Sciences and Institute of Biochemistry II, Medical Faculty, Goethe University, Frankfurt, Germany
| | - Christian Pohl
- Buchmann Institute for Molecular Life Sciences and Institute of Biochemistry II, Medical Faculty, Goethe University, Frankfurt, Germany
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7
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Murphy KJ, Reed DA, Trpceski M, Herrmann D, Timpson P. Quantifying and visualising the nuances of cellular dynamics in vivo using intravital imaging. Curr Opin Cell Biol 2021; 72:41-53. [PMID: 34091131 DOI: 10.1016/j.ceb.2021.04.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 04/23/2021] [Accepted: 04/28/2021] [Indexed: 12/14/2022]
Abstract
Intravital imaging is a powerful technology used to quantify and track dynamic changes in live cells and tissues within an intact environment. The ability to watch cell biology in real-time 'as it happens' has provided novel insight into tissue homeostasis, as well as disease initiation, progression and response to treatment. In this minireview, we highlight recent advances in the field of intravital microscopy, touching upon advances in awake versus anaesthesia-based approaches, as well as the integration of biosensors into intravital imaging. We also discuss current challenges that, in our opinion, need to be overcome to further advance the field of intravital imaging at the single-cell, subcellular and molecular resolution to reveal nuances of cell behaviour that can be targeted in complex disease settings.
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Affiliation(s)
- Kendelle J Murphy
- Garvan Institute of Medical Research & The Kinghorn Cancer Centre, Cancer Theme, Sydney, NSW, 2010, Australia; St Vincent's Clinical School, Faculty of Medicine, UNSW Sydney, Sydney, NSW, 2010, Australia
| | - Daniel A Reed
- Garvan Institute of Medical Research & The Kinghorn Cancer Centre, Cancer Theme, Sydney, NSW, 2010, Australia; St Vincent's Clinical School, Faculty of Medicine, UNSW Sydney, Sydney, NSW, 2010, Australia
| | - Michael Trpceski
- Garvan Institute of Medical Research & The Kinghorn Cancer Centre, Cancer Theme, Sydney, NSW, 2010, Australia
| | - David Herrmann
- Garvan Institute of Medical Research & The Kinghorn Cancer Centre, Cancer Theme, Sydney, NSW, 2010, Australia; St Vincent's Clinical School, Faculty of Medicine, UNSW Sydney, Sydney, NSW, 2010, Australia.
| | - Paul Timpson
- Garvan Institute of Medical Research & The Kinghorn Cancer Centre, Cancer Theme, Sydney, NSW, 2010, Australia; St Vincent's Clinical School, Faculty of Medicine, UNSW Sydney, Sydney, NSW, 2010, Australia.
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8
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Drewnik ED, Wiesenfahrt T, Smit RB, Park YJ, Pallotto LM, Mains PE. Tissue-specific regulation of epidermal contraction during C. elegans embryonic morphogenesis. G3-GENES GENOMES GENETICS 2021; 11:6273666. [PMID: 33974063 PMCID: PMC8495928 DOI: 10.1093/g3journal/jkab164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 05/05/2021] [Indexed: 11/17/2022]
Abstract
Actin and myosin mediate the epidermal cell contractions that elongate the Caenorhabditis elegans embryo from an ovoid to a tubular-shaped worm. Contraction occurs mainly in the lateral epidermal cells, while the dorsoventral epidermis plays a more passive role. Two parallel pathways trigger actinomyosin contraction, one mediated by LET-502/Rho kinase and the other by PAK-1/p21 activated kinase. A number of genes mediating morphogenesis have been shown to be sufficient when expressed either laterally or dorsoventrally. Additional genes show either lateral or dorsoventral phenotypes. This led us to a model where contractile genes have discrete functions in one or the other cell type. We tested this by examining several genes for either lateral or dorsoventral sufficiency. LET-502 expression in the lateral cells was sufficient to drive elongation. MEL-11/Myosin phosphatase, which antagonizes contraction, and PAK-1 were expected to function dorsoventrally, but we could not detect tissue-specific sufficiency. Double mutants of lethal alleles predicted to decrease lateral contraction with those thought to increase dorsoventral force were previously shown to be viable. We hypothesized that these mutant combinations shifted the contractile force from the lateral to the dorsoventral cells and so the embryos would elongate with less lateral cell contraction. This was tested by examining 10 single and double mutant strains. In most cases, elongation proceeded without a noticeable alteration in lateral contraction. We suggest that many embryonic elongation genes likely act in both lateral and dorsoventral cells, even though they may have their primary focus in one or the other cell type.
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Affiliation(s)
- Elizabeth D Drewnik
- Department of Biochemistry and Molecular Biology, Alberta Children’s Hospital Research Institute, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Tobias Wiesenfahrt
- Department of Biochemistry and Molecular Biology, Alberta Children’s Hospital Research Institute, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Ryan B Smit
- Department of Biochemistry and Molecular Biology, Alberta Children’s Hospital Research Institute, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Ye-Jean Park
- Department of Biochemistry and Molecular Biology, Alberta Children’s Hospital Research Institute, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Linda M Pallotto
- Department of Biochemistry and Molecular Biology, Alberta Children’s Hospital Research Institute, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Paul E Mains
- Department of Biochemistry and Molecular Biology, Alberta Children’s Hospital Research Institute, University of Calgary, Calgary, AB T2N 4N1, Canada
- Corresponding author: Department of Biochemistry and Molecular Biology, University of Calgary, 3330 Hospital Dr. NW, Calgary, AB T2N 4N1, Canada.
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9
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Perez-Vale KZ, Peifer M. Orchestrating morphogenesis: building the body plan by cell shape changes and movements. Development 2020; 147:dev191049. [PMID: 32917667 PMCID: PMC7502592 DOI: 10.1242/dev.191049] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
During embryonic development, a simple ball of cells re-shapes itself into the elaborate body plan of an animal. This requires dramatic cell shape changes and cell movements, powered by the contractile force generated by actin and myosin linked to the plasma membrane at cell-cell and cell-matrix junctions. Here, we review three morphogenetic events common to most animals: apical constriction, convergent extension and collective cell migration. Using the fruit fly Drosophila as an example, we discuss recent work that has revealed exciting new insights into the molecular mechanisms that allow cells to change shape and move without tearing tissues apart. We also point out parallel events at work in other animals, which suggest that the mechanisms underlying these morphogenetic processes are conserved.
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Affiliation(s)
- Kia Z Perez-Vale
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Mark Peifer
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Department of Biology, University of North Carolina at Chapel Hill, CB#3280, Chapel Hill, NC 27599-3280, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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10
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Game of Tissues: How the Epidermis Thrones C. elegans Shape. J Dev Biol 2020; 8:jdb8010007. [PMID: 32182901 PMCID: PMC7151205 DOI: 10.3390/jdb8010007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 03/05/2020] [Accepted: 03/06/2020] [Indexed: 12/14/2022] Open
Abstract
The versatility of epithelial cell structure is universally exploited by organisms in multiple contexts. Epithelial cells can establish diverse polarized axes within their tridimensional structure which enables them to flexibly communicate with their neighbors in a 360° range. Hence, these cells are central to multicellularity, and participate in diverse biological processes such as organismal development, growth or immune response and their misfunction ultimately impacts disease. During the development of an organism, the first task epidermal cells must complete is the formation of a continuous sheet, which initiates its own morphogenic process. In this review, we will focus on the C. elegans embryonic epithelial morphogenesis. We will describe how its formation, maturation, and spatial arrangements set the final shape of the nematode C. elegans. Special importance will be given to the tissue-tissue interactions, regulatory tissue-tissue feedback mechanisms and the players orchestrating the process.
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11
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Parreno J, Fowler VM. Multifunctional roles of tropomodulin-3 in regulating actin dynamics. Biophys Rev 2018; 10:1605-1615. [PMID: 30430457 DOI: 10.1007/s12551-018-0481-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 11/08/2018] [Indexed: 12/12/2022] Open
Abstract
Tropomodulins (Tmods) are proteins that cap the slow-growing (pointed) ends of actin filaments (F-actin). The basis for our current understanding of Tmod function comes from studies in cells with relatively stable and highly organized F-actin networks, leading to the view that Tmod capping functions principally to preserve F-actin stability. However, not only is Tmod capping dynamic, but it also can play major roles in regulating diverse cellular processes involving F-actin remodeling. Here, we highlight the multifunctional roles of Tmod with a focus on Tmod3. Like other Tmods, Tmod3 binds tropomyosin (Tpm) and actin, capping pure F-actin at submicromolar and Tpm-coated F-actin at nanomolar concentrations. Unlike other Tmods, Tmod3 can also bind actin monomers and its ability to bind actin is inhibited by phosphorylation of Tmod3 by Akt2. Tmod3 is ubiquitously expressed and is present in a diverse array of cytoskeletal structures, including contractile structures such as sarcomere-like units of actomyosin stress fibers and in the F-actin network encompassing adherens junctions. Tmod3 participates in F-actin network remodeling in lamellipodia during cell migration and in the assembly of specialized F-actin networks during exocytosis. Furthermore, Tmod3 is required for development, regulating F-actin mesh formation during meiosis I of mouse oocytes, erythroblast enucleation in definitive erythropoiesis, and megakaryocyte morphogenesis in the mouse fetal liver. Thus, Tmod3 plays vital roles in dynamic and stable F-actin networks in cell physiology and development, with further research required to delineate the mechanistic details of Tmod3 regulation in the aforementioned processes, or in other yet to be discovered processes.
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Affiliation(s)
- Justin Parreno
- Department of Molecular Medicine, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Velia M Fowler
- Department of Molecular Medicine, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA, 92037, USA.
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12
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Markwardt ML, Snell NE, Guo M, Wu Y, Christensen R, Liu H, Shroff H, Rizzo MA. A Genetically Encoded Biosensor Strategy for Quantifying Non-muscle Myosin II Phosphorylation Dynamics in Living Cells and Organisms. Cell Rep 2018; 24:1060-1070.e4. [PMID: 30044973 PMCID: PMC6117825 DOI: 10.1016/j.celrep.2018.06.088] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 05/25/2018] [Accepted: 06/20/2018] [Indexed: 02/06/2023] Open
Abstract
Complex cell behaviors require dynamic control over non-muscle myosin II (NMMII) regulatory light chain (RLC) phosphorylation. Here, we report that RLC phosphorylation can be tracked in living cells and organisms using a homotransfer fluorescence resonance energy transfer (FRET) approach. Fluorescent protein-tagged RLCs exhibit FRET in the dephosphorylated conformation, permitting identification and quantification of RLC phosphorylation in living cells. This approach is versatile and can accommodate several different fluorescent protein colors, thus enabling multiplexed imaging with complementary biosensors. In fibroblasts, dynamic myosin phosphorylation was observed at the leading edge of migrating cells and retracting structures where it persistently colocalized with activated myosin light chain kinase. Changes in myosin phosphorylation during C. elegans embryonic development were tracked using polarization inverted selective-plane illumination microscopy (piSPIM), revealing a shift in phosphorylated myosin localization to a longitudinal orientation following the onset of twitching. Quantitative analyses further suggested that RLC phosphorylation dynamics occur independently from changes in protein expression.
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Affiliation(s)
- Michele L Markwardt
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Nicole E Snell
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Min Guo
- Section on High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, US NIH, Bethesda, MD 20814, USA
| | - Yicong Wu
- Section on High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, US NIH, Bethesda, MD 20814, USA
| | - Ryan Christensen
- Section on High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, US NIH, Bethesda, MD 20814, USA
| | - Huafeng Liu
- State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Hari Shroff
- Section on High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, US NIH, Bethesda, MD 20814, USA
| | - M A Rizzo
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
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13
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Correction: HMP-1/α-catenin promotes junctional mechanical integrity during morphogenesis. PLoS One 2018; 13:e0195419. [PMID: 29596525 PMCID: PMC5875882 DOI: 10.1371/journal.pone.0195419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
[This corrects the article DOI: 10.1371/journal.pone.0193279.].
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