1
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Aguilar G, Bauer M, Vigano MA, Schnider ST, Brügger L, Jiménez-Jiménez C, Guerrero I, Affolter M. Seamless knockins in Drosophila via CRISPR-triggered single-strand annealing. Dev Cell 2024; 59:2672-2686.e5. [PMID: 38971155 DOI: 10.1016/j.devcel.2024.06.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 12/06/2023] [Accepted: 06/07/2024] [Indexed: 07/08/2024]
Abstract
CRISPR-Cas greatly facilitated the integration of exogenous sequences into specific loci. However, knockin generation in multicellular animals remains challenging, partially due to the complexity of insertion screening. Here, we describe SEED/Harvest, a method to generate knockins in Drosophila, based on CRISPR-Cas and the single-strand annealing (SSA) repair pathway. In SEED (from "scarless editing by element deletion"), a switchable cassette is first integrated into the target locus. In a subsequent CRISPR-triggered repair event, resolved by SSA, the cassette is seamlessly removed. Germline excision of SEED cassettes allows for fast and robust knockin generation of both fluorescent proteins and short protein tags in tandem. Tissue-specific expression of Cas9 results in somatic cassette excision, conferring spatiotemporal control of protein labeling and the conditional rescue of mutants. Finally, to achieve conditional protein labeling and manipulation of short tag knockins, we developed a genetic toolbox by functionalizing the ALFA nanobody.
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Affiliation(s)
- Gustavo Aguilar
- Growth & Development, Biozentrum, University of Basel, Spitalstrasse 41, 4056 Basel, Switzerland
| | - Milena Bauer
- Growth & Development, Biozentrum, University of Basel, Spitalstrasse 41, 4056 Basel, Switzerland
| | - M Alessandra Vigano
- Growth & Development, Biozentrum, University of Basel, Spitalstrasse 41, 4056 Basel, Switzerland
| | - Sophie T Schnider
- Growth & Development, Biozentrum, University of Basel, Spitalstrasse 41, 4056 Basel, Switzerland
| | - Lukas Brügger
- Growth & Development, Biozentrum, University of Basel, Spitalstrasse 41, 4056 Basel, Switzerland
| | - Carlos Jiménez-Jiménez
- Tissue and Organ Homeostasis, Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Universidad Autónoma de Madrid, Nicolás Cabrera 1, Madrid, Spain
| | - Isabel Guerrero
- Tissue and Organ Homeostasis, Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Universidad Autónoma de Madrid, Nicolás Cabrera 1, Madrid, Spain
| | - Markus Affolter
- Growth & Development, Biozentrum, University of Basel, Spitalstrasse 41, 4056 Basel, Switzerland.
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2
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Inaki M, Higashi T, Okuda S, Matsuno K. Distinct cellular and junctional dynamics independently regulate the rotation and elongation of the embryonic gut in Drosophila. PLoS Genet 2024; 20:e1011422. [PMID: 39374304 DOI: 10.1371/journal.pgen.1011422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Accepted: 09/06/2024] [Indexed: 10/09/2024] Open
Abstract
Complex organ structures are formed with high reproducibility. To achieve such intricate morphologies, the responsible epithelium undergoes multiple simultaneous shape changes, such as elongation and folding. However, these changes have typically been assessed separately. In this study, we revealed how distinct shape changes are controlled during internal organ morphogenesis. The Drosophila embryonic hindgut undergoes left-right asymmetric rotation and anteroposterior elongation in a tissue-autonomous manner driven by cell sliding and convergent extension, respectively, in the hindgut epithelia. However, the regulation of these processes remains unclear. Through genetic analysis and live imaging, we demonstrated that cell sliding and convergent extension are independently regulated by Myosin1D and E-cadherin, and Par-3, respectively, whereas both require MyosinII activity. Using a mathematical model, we demonstrated that independently regulated cellular dynamics can simultaneously cause shape changes in a single mechanical system using anisotropic edge contraction. Our findings indicate that distinct cellular dynamics sharing a common apparatus can be independently and simultaneously controlled to form complex organ shapes. This suggests that such a mechanism may be a general strategy during complex tissue morphogenesis.
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Affiliation(s)
- Mikiko Inaki
- Department of Life Sciences, Graduate School of Science, University of Hyogo, Hyogo, Japan
- Department of Biological Sciences, Graduate School of Science, The University of Osaka, Toyonaka, Osaka, Japan
| | - Takamasa Higashi
- Department of Biological Sciences, Graduate School of Science, The University of Osaka, Toyonaka, Osaka, Japan
| | - Satoru Okuda
- Nano Life Science Institute, Kanazawa University, Kanazawa, Japan
| | - Kenji Matsuno
- Department of Biological Sciences, Graduate School of Science, The University of Osaka, Toyonaka, Osaka, Japan
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3
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Warder BN, Nelson KA, Sui J, Anllo L, DiNardo S. An actomyosin network organizes niche morphology and responds to feedback from recruited stem cells. Curr Biol 2024; 34:3917-3930.e6. [PMID: 39137785 PMCID: PMC11387155 DOI: 10.1016/j.cub.2024.07.041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 04/18/2024] [Accepted: 07/10/2024] [Indexed: 08/15/2024]
Abstract
Stem cells often rely on signals from a niche, which in many tissues adopts a precise morphology. What remains elusive is how niches are formed and how morphology impacts function. To address this, we leverage the Drosophila gonadal niche, which affords genetic tractability and live-imaging. We have previously shown mechanisms dictating niche cell migration to their appropriate position within the gonad and the resultant consequences on niche function. Here, we show that once positioned, niche cells robustly polarize filamentous actin (F-actin) and non-muscle myosin II (MyoII) toward neighboring germ cells. Actomyosin tension along the niche periphery generates a highly reproducible smoothened contour. Without contractility, niches are misshapen and exhibit defects in their ability to regulate germline stem cell behavior. We additionally show that germ cells aid in polarizing MyoII within niche cells and that extrinsic input is required for niche morphogenesis and function. Our work reveals a feedback mechanism where stem cells shape the niche that guides their behavior.
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Affiliation(s)
- Bailey N Warder
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Kara A Nelson
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Justin Sui
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Lauren Anllo
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Stephen DiNardo
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Institute for Regenerative Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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4
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Warder BN, Nelson KA, Sui J, Anllo L, DiNardo S. An actomyosin network organizes niche morphology and responds to feedback from recruited stem cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.09.08.556877. [PMID: 38746236 PMCID: PMC11092431 DOI: 10.1101/2023.09.08.556877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Stem cells often rely on signals from a niche, which in many tissues adopts a precise morphology. What remains elusive is how niches are formed, and how morphology impacts function. To address this, we leverage the Drosophila gonadal niche, which affords genetic tractability and live-imaging. We have previously shown mechanisms dictating niche cell migration to their appropriate position within the gonad, and the resultant consequences on niche function. Here, we show that once positioned, niche cells robustly polarize filamentous actin (F-actin) and Non-muscle Myosin II (MyoII) towards neighboring germ cells. Actomyosin tension along the niche periphery generates a highly reproducible smoothened contour. Without contractility, niches are misshapen and exhibit defects in their ability to regulate germline stem cell behavior. We additionally show that germ cells aid in polarizing MyoII within niche cells, and that extrinsic input is required for niche morphogenesis and function. Our work reveals a feedback mechanism where stem cells shape the niche that guides their behavior.
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Affiliation(s)
- Bailey N. Warder
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Kara A. Nelson
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Justin Sui
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Lauren Anllo
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Stephen DiNardo
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Institute for Regenerative Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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5
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Luciano M, Versaevel M, Kalukula Y, Gabriele S. Mechanoresponse of Curved Epithelial Monolayers Lining Bowl-Shaped 3D Microwells. Adv Healthc Mater 2024; 13:e2203377. [PMID: 37820698 DOI: 10.1002/adhm.202203377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Indexed: 10/13/2023]
Abstract
The optimal functioning of many organs relies on the curved architecture of their epithelial tissues. However, the mechanoresponse of epithelia to changes in curvature remains misunderstood. Here, bowl-shaped microwells in hydrogels are designed via photopolymerization to faithfully replicate the shape and dimensions of lobular structures. Leveraging these hydrogel-based microwells, curved epithelial monolayers are engineered, and how in-plane and Gaussian curvatures at the microwell entrance influence epithelial behavior is investigated. Cells and nuclei around the microwell edge display a more pronounced centripetal orientation as the in-plane curvature decreases, and enhanced cell straightness and speed. Moreover, cells reorganize their actin cytoskeleton by forming a supracellular actin cable at the microwell edge, with its size becoming more pronounced as the in-plane curvature decreases. The Gaussian curvature at the microwell entrance enhances the maturation of the supracellular actin cable architecture and leads to a vertical orientation of nuclei toward the bottom of the microwell. Increasing Gaussian curvature results in flattened and elongated nuclear morphologies characterized by highly compacted chromatin states. This approach provides better understanding of the mechanoresponse of curved epithelial monolayers curvatures lining lobular structures. In addition, bowl-shaped microwells offer a powerful platform to study curvature-dependent mechanotransduction pathways in anatomically relevant 3D structures.
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Affiliation(s)
- Marine Luciano
- Mechanobiology & Biomaterials Group, Research Institute for Biosciences, University of Mons, 20 Place du Parc, Mons, B-7000, Belgium
| | - Marie Versaevel
- Mechanobiology & Biomaterials Group, Research Institute for Biosciences, University of Mons, 20 Place du Parc, Mons, B-7000, Belgium
| | - Yohalie Kalukula
- Mechanobiology & Biomaterials Group, Research Institute for Biosciences, University of Mons, 20 Place du Parc, Mons, B-7000, Belgium
| | - Sylvain Gabriele
- Mechanobiology & Biomaterials Group, Research Institute for Biosciences, University of Mons, 20 Place du Parc, Mons, B-7000, Belgium
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6
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Clements R, Smith T, Cowart L, Zhumi J, Sherrod A, Cahill A, Hunter GL. Myosin XV is a negative regulator of signaling filopodia during long-range lateral inhibition. Dev Biol 2024; 505:110-121. [PMID: 37956923 PMCID: PMC10767839 DOI: 10.1016/j.ydbio.2023.11.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 10/30/2023] [Accepted: 11/06/2023] [Indexed: 11/20/2023]
Abstract
The self-organization of cells during development is essential for the formation of healthy tissues and requires the coordination of cell activities at local scales. Cytonemes, or signaling filopodia, are dynamic actin-based cellular protrusions that allow cells to engage in contact mediated signaling at a distance. While signaling filopodia have been shown to support several signaling paradigms during development, less is understood about how these protrusions are regulated. We investigated the role of the plus-end directed, unconventional MyTH4-FERM myosins in regulating signaling filopodia during sensory bristle patterning on the dorsal thorax of the fruit fly Drosophila melanogaster. We found that Myosin XV is required for regulating signaling filopodia dynamics and, as a consequence, lateral inhibition more broadly throughout the patterning epithelium. We found that Myosin XV is required for limiting the length and number of signaling filopodia generated by bristle precursor cells. Cells with additional and longer signaling filopodia due to loss of Myosin XV are not signaling competent, due to altered levels of Delta ligand and Notch receptor along their lengths. We conclude that Myosin XV acts to negatively regulate signaling filopodia, as well as promote the ability of signaling filopodia to engage in long-range Notch signaling. Since Myosin XV isoforms are present across several vertebrate and invertebrate systems, this may have significance for other long-range signaling mechanisms.
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Affiliation(s)
- Rhiannon Clements
- Department of Biology, Clarkson University, Potsdam, NY, 13699, United States
| | - Tyler Smith
- Department of Biology, Clarkson University, Potsdam, NY, 13699, United States
| | - Luke Cowart
- Department of Biology, Clarkson University, Potsdam, NY, 13699, United States
| | - Jennifer Zhumi
- Department of Biology, Clarkson University, Potsdam, NY, 13699, United States
| | - Alan Sherrod
- Department of Biology, Clarkson University, Potsdam, NY, 13699, United States
| | - Aidan Cahill
- Department of Biology, Clarkson University, Potsdam, NY, 13699, United States
| | - Ginger L Hunter
- Department of Biology, Clarkson University, Potsdam, NY, 13699, United States.
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7
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Tah I, Haertter D, Crawford JM, Kiehart DP, Schmidt CF, Liu AJ. Minimal vertex model explains how the amnioserosa avoids fluidization during Drosophila dorsal closure. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.20.572544. [PMID: 38187730 PMCID: PMC10769242 DOI: 10.1101/2023.12.20.572544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Dorsal closure is a process that occurs during embryogenesis of Drosophila melanogaster . During dorsal closure, the amnioserosa (AS), a one-cell thick epithelial tissue that fills the dorsal opening, shrinks as the lateral epidermis sheets converge and eventually merge. During this process, the aspect ratio of amnioserosa cells increases markedly. The standard 2-dimensional vertex model, which successfully describes tissue sheet mechanics in multiple contexts, would in this case predict that the tissue should fluidize via cell neighbor changes. Surprisingly, however, the amnioserosa remains an elastic solid with no such events. We here present a minimal extension to the vertex model that explains how the amnioserosa can achieve this unexpected behavior. We show that continuous shrinkage of the preferred cell perimeter and cell perimeter polydispersity lead to the retention of the solid state of the amnioserosa. Our model accurately captures measured cell shape and orientation changes and predicts non-monotonic junction tension that we confirm with laser ablation experiments. Significance Statement During embryogenesis, cells in tissues can undergo significant shape changes. Many epithelial tissues fluidize, i.e. cells exchange neighbors, when the average cell aspect ratio increases above a threshold value, consistent with the standard vertex model. During dorsal closure in Drosophila melanogaster , however, the amnioserosa tissue remains solid even as the average cell aspect ratio increases well above threshold. We introduce perimeter polydispersity and allow the preferred cell perimeters, usually held fixed in vertex models, to decrease linearly with time as seen experimentally. With these extensions to the standard vertex model, we capture experimental observations quantitatively. Our results demonstrate that vertex models can describe the behavior of the amnioserosa in dorsal closure by allowing normally fixed parameters to vary with time.
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8
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Clements R, Smith T, Cowart L, Zhumi J, Sherrod A, Cahill A, Hunter GL. Myosin XV is a negative regulator of signaling filopodia during long-range lateral inhibition. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.07.547992. [PMID: 37461640 PMCID: PMC10350058 DOI: 10.1101/2023.07.07.547992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
The self-organization of cells during development is essential for the formation of healthy tissues, and requires the coordination of cell activities at local scales. Cytonemes, or signaling filopodia, are dynamic actin-based cellular protrusions that allow cells to engage in contact mediated signaling at a distance. While signaling filopodia have been shown to support several signaling paradigms during development, less is understood about how these protrusions are regulated. We investigated the role of the plus-end directed, unconventional MyTH4-FERM myosins in regulating signaling filopodia during sensory bristle patterning on the dorsal thorax of the fruit fly Drosophila melanogaster. We found that Myosin XV is required for regulating signaling filopodia dynamics and, as a consequence, lateral inhibition more broadly throughout the patterning epithelium. We found that Myosin XV is required for limiting the length and number of signaling filopodia generated by bristle precursor cells. Cells with additional and longer signaling filopodia due to loss of Myosin XV are not signaling competent, due to altered levels of Delta ligand and Notch receptor along their lengths. We conclude that Myosin XV acts to negatively regulate signaling filopodia, as well as promote the ability of signaling filopodia to engage in long-range Notch signaling. Since Myosin XV is present across several vertebrate and invertebrate systems, this may have significance for other long-range signaling mechanisms.
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Affiliation(s)
| | - Tyler Smith
- Department of Biology, Clarkson University, Potsdam, NY, 13699, USA
| | - Luke Cowart
- Department of Biology, Clarkson University, Potsdam, NY, 13699, USA
| | - Jennifer Zhumi
- Department of Biology, Clarkson University, Potsdam, NY, 13699, USA
| | - Alan Sherrod
- Department of Biology, Clarkson University, Potsdam, NY, 13699, USA
| | - Aidan Cahill
- Department of Biology, Clarkson University, Potsdam, NY, 13699, USA
| | - Ginger L Hunter
- Department of Biology, Clarkson University, Potsdam, NY, 13699, USA
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9
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Balaghi N, Erdemci-Tandogan G, McFaul C, Fernandez-Gonzalez R. Myosin waves and a mechanical asymmetry guide the oscillatory migration of Drosophila cardiac progenitors. Dev Cell 2023:S1534-5807(23)00238-1. [PMID: 37295436 DOI: 10.1016/j.devcel.2023.05.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 02/27/2023] [Accepted: 05/16/2023] [Indexed: 06/12/2023]
Abstract
Heart development begins with the formation of a tube as cardiac progenitors migrate from opposite sides of the embryo. Abnormal cardiac progenitor movements cause congenital heart defects. However, the mechanisms of cell migration during early heart development remain poorly understood. Using quantitative microscopy, we found that in Drosophila embryos, cardiac progenitors (cardioblasts) migrated through a sequence of forward and backward steps. Cardioblast steps were associated with oscillatory non-muscle myosin II waves that induced periodic shape changes and were necessary for timely heart tube formation. Mathematical modeling predicted that forward cardioblast migration required a stiff boundary at the trailing edge. Consistent with this, we found a supracellular actin cable at the trailing edge of the cardioblasts that limited the amplitude of the backward steps, thus biasing the direction of cell movement. Our results indicate that periodic shape changes coupled with a polarized actin cable produce asymmetrical forces that promote cardioblast migration.
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Affiliation(s)
- Negar Balaghi
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada; Translational Biology and Engineering Program, Ted Rogers Centre for Heart Research, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Gonca Erdemci-Tandogan
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada; Translational Biology and Engineering Program, Ted Rogers Centre for Heart Research, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Christopher McFaul
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada; Translational Biology and Engineering Program, Ted Rogers Centre for Heart Research, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Rodrigo Fernandez-Gonzalez
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada; Translational Biology and Engineering Program, 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 M5G 1X8, Canada.
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10
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Van Essen DC. Biomechanical models and mechanisms of cellular morphogenesis and cerebral cortical expansion and folding. Semin Cell Dev Biol 2023; 140:90-104. [PMID: 35840524 PMCID: PMC9942585 DOI: 10.1016/j.semcdb.2022.06.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Revised: 05/31/2022] [Accepted: 06/16/2022] [Indexed: 01/28/2023]
Abstract
Morphogenesis of the nervous system involves a highly complex spatio-temporal pattern of physical forces (mainly tension and pressure) acting on cells and tissues that are pliable but have an intricately organized cytoskeletal infrastructure. This review begins by covering basic principles of biomechanics and the core cytoskeletal toolkit used to regulate the shapes of cells and tissues during embryogenesis and neural development. It illustrates how the principle of 'tensegrity' provides a useful conceptual framework for understanding how cells dynamically respond to forces that are generated internally or applied externally. The latter part of the review builds on this foundation in considering the development of mammalian cerebral cortex. The main focus is on cortical expansion and folding - processes that take place over an extended period of prenatal and postnatal development. Cortical expansion and folding are likely to involve many complementary mechanisms, some related to regulating cell proliferation and migration and others related to specific types and patterns of mechanical tension and pressure. Three distinct multi-mechanism models are evaluated in relation to a set of 18 key experimental observations and findings. The Composite Tension Plus (CT+) model is introduced as an updated version of a previous multi-component Differential Expansion Sandwich Plus (DES+) model (Van Essen, 2020); the new CT+ model includes 10 distinct mechanisms and has the greatest explanatory power among published models to date. Much needs to be done in order to validate specific mechanistic components and to assess their relative importance in different species, and important directions for future research are suggested.
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11
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Serna-Morales E, Sánchez-Sánchez BJ, Marcotti S, Nichols A, Bhargava A, Dragu A, Hirvonen LM, Díaz-de-la-Loza MDC, Mink M, Cox S, Rayfield E, Lee RM, Hobson CM, Chew TL, Stramer BM. Extracellular matrix assembly stress initiates Drosophila central nervous system morphogenesis. Dev Cell 2023; 58:825-835.e6. [PMID: 37086718 PMCID: PMC10390342 DOI: 10.1016/j.devcel.2023.03.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 12/12/2022] [Accepted: 03/05/2023] [Indexed: 04/24/2023]
Abstract
Forces controlling tissue morphogenesis are attributed to cellular-driven activities, and any role for extracellular matrix (ECM) is assumed to be passive. However, all polymer networks, including ECM, can develop autonomous stresses during their assembly. Here, we examine the morphogenetic function of an ECM before reaching homeostatic equilibrium by analyzing de novo ECM assembly during Drosophila ventral nerve cord (VNC) condensation. Asymmetric VNC shortening and a rapid decrease in surface area correlate with the exponential assembly of collagen IV (Col4) surrounding the tissue. Concomitantly, a transient developmentally induced Col4 gradient leads to coherent long-range flow of ECM, which equilibrates the Col4 network. Finite element analysis and perturbation of Col4 network formation through the generation of dominant Col4 mutations that affect assembly reveal that VNC morphodynamics is partially driven by a sudden increase in ECM-driven surface tension. These data suggest that ECM assembly stress and associated network instabilities can actively participate in tissue morphogenesis.
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Affiliation(s)
- Eduardo Serna-Morales
- Randall Centre for Cell and Molecular Biophysics, King's College London, SE1 1UL London, UK
| | | | - Stefania Marcotti
- Randall Centre for Cell and Molecular Biophysics, King's College London, SE1 1UL London, UK
| | - Angus Nichols
- Randall Centre for Cell and Molecular Biophysics, King's College London, SE1 1UL London, UK
| | - Anushka Bhargava
- Randall Centre for Cell and Molecular Biophysics, King's College London, SE1 1UL London, UK
| | - Anca Dragu
- Randall Centre for Cell and Molecular Biophysics, King's College London, SE1 1UL London, UK
| | - Liisa M Hirvonen
- Randall Centre for Cell and Molecular Biophysics, King's College London, SE1 1UL London, UK
| | | | - Matyas Mink
- Institute of Medical Biology, University of Szeged, 6720 Szeged, Hungary
| | - Susan Cox
- Randall Centre for Cell and Molecular Biophysics, King's College London, SE1 1UL London, UK
| | - Emily Rayfield
- School of Earth Sciences, University of Bristol, BS8 1QU Bristol, UK
| | - Rachel M Lee
- Advanced Imaging Center, Howard Hughes Medical Institute Janelia Research Campus, Ashburn, VA 20147, USA
| | - Chad M Hobson
- Advanced Imaging Center, Howard Hughes Medical Institute Janelia Research Campus, Ashburn, VA 20147, USA
| | - Teng-Leong Chew
- Advanced Imaging Center, Howard Hughes Medical Institute Janelia Research Campus, Ashburn, VA 20147, USA
| | - Brian M Stramer
- Randall Centre for Cell and Molecular Biophysics, King's College London, SE1 1UL London, UK.
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12
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Baldwin AT, Kim JH, Wallingford JB. In vivo high-content imaging and regression analysis reveal non-cell autonomous functions of Shroom3 during neural tube closure. Dev Biol 2022; 491:105-112. [PMID: 36113571 PMCID: PMC10118288 DOI: 10.1016/j.ydbio.2022.08.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Revised: 08/02/2022] [Accepted: 08/28/2022] [Indexed: 11/24/2022]
Abstract
During neural tube closure, neural ectoderm cells constrict their apical surfaces to bend and fold the tissue into a tube that will become the central nervous system. Recent data from mice and humans with neural tube defects suggest that key genes required for neural tube closure can exert non-cell autonomous effects on cell behavior, but the nature of these effects remains obscure. Here, we coupled tissue-scale, high-resolution time-lapse imaging of the closing neural tube of Xenopus to multivariate regression modeling, and we show that medial actin accumulation drives apical constriction non-autonomously in neighborhoods of cells, rather than solely in individual cells. To further explore this effect, we examined mosaic crispant embryos and identified both autonomous and non-autonomous effects of the apical constriction protein Shroom3.
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Affiliation(s)
- Austin T Baldwin
- Dept. of Molecular Biosciences, University of Texas at Austin, United States
| | - Juliana H Kim
- Dept. of Molecular Biosciences, University of Texas at Austin, United States
| | - John B Wallingford
- Dept. of Molecular Biosciences, University of Texas at Austin, United States.
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13
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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].
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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
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14
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Johnson SL, Prifti MV, Sujkowski A, Libohova K, Blount JR, Hong L, Tsou WL, Todi SV. Drosophila as a Model of Unconventional Translation in Spinocerebellar Ataxia Type 3. Cells 2022; 11:cells11071223. [PMID: 35406787 PMCID: PMC8997593 DOI: 10.3390/cells11071223] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Revised: 03/29/2022] [Accepted: 03/31/2022] [Indexed: 12/21/2022] Open
Abstract
RNA toxicity contributes to diseases caused by anomalous nucleotide repeat expansions. Recent work demonstrated RNA-based toxicity from repeat-associated, non-AUG-initiated translation (RAN translation). RAN translation occurs around long nucleotide repeats that form hairpin loops, allowing for translation initiation in the absence of a start codon that results in potentially toxic, poly-amino acid repeat-containing proteins. Discovered in Spinocerebellar Ataxia Type (SCA) 8, RAN translation has been documented in several repeat-expansion diseases, including in the CAG repeat-dependent polyglutamine (polyQ) disorders. The ATXN3 gene, which causes SCA3, also known as Machado–Joseph Disease (MJD), contains a CAG repeat that is expanded in disease. ATXN3 mRNA possesses features linked to RAN translation. In this paper, we examined the potential contribution of RAN translation to SCA3/MJD in Drosophila by using isogenic lines that contain homomeric or interrupted CAG repeats. We did not observe unconventional translation in fly neurons or glia. However, our investigations indicate differential toxicity from ATXN3 protein-encoding mRNA that contains pure versus interrupted CAG repeats. Additional work suggests that this difference may be due in part to toxicity from homomeric CAG mRNA. We conclude that Drosophila is not suitable to model RAN translation for SCA3/MJD, but offers clues into the potential pathogenesis stemming from CAG repeat-containing mRNA in this disorder.
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Affiliation(s)
- Sean L. Johnson
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI 48201, USA; (S.L.J.); (M.V.P.); (A.S.); (K.L.); (J.R.B.); (L.H.); (W.-L.T.)
| | - Matthew V. Prifti
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI 48201, USA; (S.L.J.); (M.V.P.); (A.S.); (K.L.); (J.R.B.); (L.H.); (W.-L.T.)
| | - Alyson Sujkowski
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI 48201, USA; (S.L.J.); (M.V.P.); (A.S.); (K.L.); (J.R.B.); (L.H.); (W.-L.T.)
| | - Kozeta Libohova
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI 48201, USA; (S.L.J.); (M.V.P.); (A.S.); (K.L.); (J.R.B.); (L.H.); (W.-L.T.)
| | - Jessica R. Blount
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI 48201, USA; (S.L.J.); (M.V.P.); (A.S.); (K.L.); (J.R.B.); (L.H.); (W.-L.T.)
| | - Luke Hong
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI 48201, USA; (S.L.J.); (M.V.P.); (A.S.); (K.L.); (J.R.B.); (L.H.); (W.-L.T.)
- Department of Neurology, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Wei-Ling Tsou
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI 48201, USA; (S.L.J.); (M.V.P.); (A.S.); (K.L.); (J.R.B.); (L.H.); (W.-L.T.)
| | - Sokol V. Todi
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI 48201, USA; (S.L.J.); (M.V.P.); (A.S.); (K.L.); (J.R.B.); (L.H.); (W.-L.T.)
- Department of Neurology, Wayne State University School of Medicine, Detroit, MI 48201, USA
- Correspondence:
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15
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Luciano M, Versaevel M, Vercruysse E, Procès A, Kalukula Y, Remson A, Deridoux A, Gabriele S. Appreciating the role of cell shape changes in the mechanobiology of epithelial tissues. BIOPHYSICS REVIEWS 2022; 3:011305. [PMID: 38505223 PMCID: PMC10903419 DOI: 10.1063/5.0074317] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 02/23/2022] [Indexed: 03/21/2024]
Abstract
The wide range of epithelial cell shapes reveals the complexity and diversity of the intracellular mechanisms that serve to construct their morphology and regulate their functions. Using mechanosensitive steps, epithelial cells can sense a variety of different mechanochemical stimuli and adapt their behavior by reshaping their morphology. These changes of cell shape rely on a structural reorganization in space and time that generates modifications of the tensional state and activates biochemical cascades. Recent studies have started to unveil how the cell shape maintenance is involved in mechanical homeostatic tasks to sustain epithelial tissue folding, identity, and self-renewal. Here, we review relevant works that integrated mechanobiology to elucidate some of the core principles of how cell shape may be conveyed into spatial information to guide collective processes such as epithelial morphogenesis. Among many other parameters, we show that the regulation of the cell shape can be understood as the result of the interplay between two counteracting mechanisms: actomyosin contractility and intercellular adhesions, and that both do not act independently but are functionally integrated to operate on molecular, cellular, and tissue scales. We highlight the role of cadherin-based adhesions in force-sensing and mechanotransduction, and we report recent developments that exploit physics of liquid crystals to connect cell shape changes to orientational order in cell aggregates. Finally, we emphasize that the further intermingling of different disciplines to develop new mechanobiology assays will lead the way toward a unified picture of the contribution of cell shape to the pathophysiological behavior of epithelial tissues.
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Affiliation(s)
- Marine Luciano
- University of Mons, Interfaces and Complex Fluids Laboratory, Mechanobiology and Biomaterials Group, Research Institute for Biosciences, CIRMAP, 20 Place du Parc, B-7000 Mons, Belgium
| | - Marie Versaevel
- University of Mons, Interfaces and Complex Fluids Laboratory, Mechanobiology and Biomaterials Group, Research Institute for Biosciences, CIRMAP, 20 Place du Parc, B-7000 Mons, Belgium
| | - Eléonore Vercruysse
- University of Mons, Interfaces and Complex Fluids Laboratory, Mechanobiology and Biomaterials Group, Research Institute for Biosciences, CIRMAP, 20 Place du Parc, B-7000 Mons, Belgium
| | - Anthony Procès
- University of Mons, Interfaces and Complex Fluids Laboratory, Mechanobiology and Biomaterials Group, Research Institute for Biosciences, CIRMAP, 20 Place du Parc, B-7000 Mons, Belgium
| | - Yohalie Kalukula
- University of Mons, Interfaces and Complex Fluids Laboratory, Mechanobiology and Biomaterials Group, Research Institute for Biosciences, CIRMAP, 20 Place du Parc, B-7000 Mons, Belgium
| | - Alexandre Remson
- University of Mons, Interfaces and Complex Fluids Laboratory, Mechanobiology and Biomaterials Group, Research Institute for Biosciences, CIRMAP, 20 Place du Parc, B-7000 Mons, Belgium
| | - Amandine Deridoux
- University of Mons, Interfaces and Complex Fluids Laboratory, Mechanobiology and Biomaterials Group, Research Institute for Biosciences, CIRMAP, 20 Place du Parc, B-7000 Mons, Belgium
| | - Sylvain Gabriele
- University of Mons, Interfaces and Complex Fluids Laboratory, Mechanobiology and Biomaterials Group, Research Institute for Biosciences, CIRMAP, 20 Place du Parc, B-7000 Mons, Belgium
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16
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Athilingam T, Parihar SS, Bhattacharya R, Rizvi MS, Kumar A, Sinha P. Proximate larval epidermal cell layer generates forces for Pupal thorax closure in Drosophila. Genetics 2022; 221:6528854. [PMID: 35166774 PMCID: PMC9071563 DOI: 10.1093/genetics/iyac030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 02/01/2022] [Indexed: 11/14/2022] Open
Abstract
During tissue closures, such as embryonic dorsal closure in Drosophila melanogaster, a proximate extra-embryonic layer, amnioserosa, generates forces that drive migration of the flanking lateral embryonic epidermis, thereby zip-shutting the embryo. Arguably, this paradigm of tissue closure is also recapitulated in mammalian wound healing wherein proximate fibroblasts transform into contractile myofibroblasts, develop cell junctions, and form a tissue layer de novo: contraction of the latter then aids in wound closure. Given this parallelism between disparate exemplars, we posit a general principle of tissue closure via proximate cell layer-generated forces. Here, we have tested this hypothesis in pupal thorax closure wherein 2 halves of the presumptive adult thorax of Drosophila, the contralateral heminotal epithelia, migrate over an underlying larval epidermal cell layer. We show that the proximate larval epidermal cell layer promotes thorax closure by its active contraction, orchestrated by its elaborate actomyosin network-driven epithelial cell dynamics, cell delamination, and death-the latter being prefigured by the activation of caspases. Larval epidermal cell dynamics generate contraction forces, which when relayed to the flanking heminota-via their mutual integrin-based adhesions-mediate thorax closure. Compromising any of these contraction force-generating mechanisms in the larval epidermal cell layer slows down heminotal migration, while loss of its relay to the flanking heminota abrogates the thorax closure altogether. Mathematical modeling further reconciles the biophysical underpinning of this emergent mechanism of thorax closure. Revealing mechanism of thorax closure apart, these findings show conservation of an essential principle of a proximate cell layer-driven tissue closure.
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Affiliation(s)
- Thamarailingam Athilingam
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Saurabh S Parihar
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Rachita Bhattacharya
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Mohd S Rizvi
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Amit Kumar
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Pradip Sinha
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur 208016, India,Corresponding author: Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur, 208016, India.
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17
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Pérez-Verdugo F, Reig G, Cerda M, Concha ML, Soto R. Geometrical characterization of active contraction pulses in epithelial cells using the two-dimensional vertex model. J R Soc Interface 2022; 19:20210851. [PMID: 35078339 PMCID: PMC8790349 DOI: 10.1098/rsif.2021.0851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 12/16/2021] [Indexed: 01/28/2023] Open
Abstract
Several models have been proposed to describe the dynamics of epithelial tissues undergoing morphogenetic changes driven by apical constriction pulses, which differ in where the constriction is applied, either at the perimeter or in the medial regions. To help discriminate between these models, we analyse the impact of where constriction is applied on the final geometry of the active contracted cell, using the two-dimensional vertex model. We find that medial activity, characterized by a reduction in the reference area, generates anisotropic cell shapes, whereas isotropic cell shapes are produced when the reference perimeter is reduced. When plasticity is included, sufficiently slow processes of medial contractile activity, compared with the characteristic times of elasticity and plasticity, cells can achieve less elongated shapes. Similarly, for perimeter activity, the highest level of contraction is achieved. Finally, we apply the model to describe the apical contractile pulses observed within the epithelial enveloping cell layer during the pre-epiboly of the annual killifish Austrolebias nigripinnis. The analysis of the cell shape changes allowed a global fit of all parameters of the vertex model, with the pulses being quantitatively captured using perimeter activity and area plasticity.
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Affiliation(s)
| | - Germán Reig
- Escuela de Tecnología Médica y del Centro Integrativo de Biología y Química Aplicada (CIBQA), Universidad Bernardo O’Higgins, Santiago, Chile
| | - Mauricio Cerda
- Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, PO Box 70031, Santiago, Chile
- Biomedical Neuroscience Institute, Independencia 1027, Santiago, Chile
- Center for Medical Informatics and Telemedicine (CIMT), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Miguel L. Concha
- Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, PO Box 70031, Santiago, Chile
- Biomedical Neuroscience Institute, Independencia 1027, Santiago, Chile
- Center for Geroscience, Brain Health and Metabolism, Santiago, Chile
| | - Rodrigo Soto
- Departamento de Física, FCFM, Universidad de Chile, Santiago, Chile
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18
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Mechano-chemical feedback mediated competition for BMP signalling leads to pattern formation. Dev Biol 2021; 481:43-51. [PMID: 34555363 DOI: 10.1016/j.ydbio.2021.09.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 09/01/2021] [Accepted: 09/15/2021] [Indexed: 11/22/2022]
Abstract
Developmental patterning is thought to be regulated by conserved signalling pathways. Initial patterns are often broad before refining to only those cells that commit to a particular fate. However, the mechanisms by which pattern refinement takes place remain to be addressed. Using the posterior crossvein (PCV) of the Drosophila pupal wing as a model, into which bone morphogenetic protein (BMP) ligand is extracellularly transported to instruct vein patterning, we investigate how pattern refinement is regulated. We found that BMP signalling induces apical enrichment of Myosin II in developing crossvein cells to regulate apical constriction. Live imaging of cellular behaviour indicates that changes in cell shape are dynamic and transient, only being maintained in those cells that retain vein fate competence after refinement. Disrupting cell shape changes throughout the PCV inhibits pattern refinement. In contrast, disrupting cell shape in only a subset of vein cells can result in a loss of BMP signalling. We propose that mechano-chemical feedback leads to competition for the developmental signal which plays a critical role in pattern refinement.
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19
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Yoo B, Kim HY, Chen X, Shen W, Jang JS, Stein SN, Cormier O, Pereira L, Shih CRY, Krieger C, Reed B, Harden N, Wang SJH. 20-hydroxyecdysone (20E) signaling regulates amnioserosa morphogenesis during Drosophila dorsal closure: EcR modulates gene expression in a complex with the AP-1 subunit, Jun. Biol Open 2021; 10:271855. [PMID: 34296248 PMCID: PMC8411571 DOI: 10.1242/bio.058605] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 07/06/2021] [Indexed: 11/25/2022] Open
Abstract
Steroid hormones influence diverse biological processes throughout the animal life cycle, including metabolism, stress resistance, reproduction, and lifespan. In insects, the steroid hormone, 20-hydroxyecdysone (20E), is the central hormone regulator of molting and metamorphosis, and plays roles in tissue morphogenesis. For example, amnioserosa contraction, which is a major driving force in Drosophila dorsal closure (DC), is defective in embryos mutant for 20E biosynthesis. Here, we show that 20E signaling modulates the transcription of several DC participants in the amnioserosa and other dorsal tissues during late embryonic development, including zipper, which encodes for non-muscle myosin. Canonical ecdysone signaling typically involves the binding of Ecdysone receptor (EcR) and Ultraspiracle heterodimers to ecdysone-response elements (EcREs) within the promoters of responsive genes to drive expression. During DC, however, we provide evidence that 20E signaling instead acts in parallel to the JNK cascade via a direct interaction between EcR and the AP-1 transcription factor subunit, Jun, which together binds to genomic regions containing AP-1 binding sites but no EcREs to control gene expression. Our work demonstrates a novel mode of action for 20E signaling in Drosophila that likely functions beyond DC, and may provide further insights into mammalian steroid hormone receptor interactions with AP-1. Summary: During Drosophila dorsal closure, 20E signaling acts non-canonically through an interaction between EcR and the AP-1 subunit, Jun, to control gene expression at regions containing AP-1 motifs but no EcREs.
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Affiliation(s)
- Byoungjoo Yoo
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Hae-Yoon Kim
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Xi Chen
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Weiping Shen
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Ji Sun Jang
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Shaianne N Stein
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Olga Cormier
- Department of Biology, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1, Canada
| | - Lionel Pereira
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Claire R Y Shih
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Charles Krieger
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Bruce Reed
- Department of Biology, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1, Canada
| | - Nicholas Harden
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Simon J H Wang
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.,Department of Biomedical Physiology and Kinesiology, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
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20
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Biehler C, Rothenberg KE, Jette A, Gaude HM, Fernandez-Gonzalez R, Laprise P. Pak1 and PP2A antagonize aPKC function to support cortical tension induced by the Crumbs-Yurt complex. eLife 2021; 10:67999. [PMID: 34212861 PMCID: PMC8282337 DOI: 10.7554/elife.67999] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 06/30/2021] [Indexed: 12/26/2022] Open
Abstract
The Drosophila polarity protein Crumbs is essential for the establishment and growth of the apical domain in epithelial cells. The protein Yurt limits the ability of Crumbs to promote apical membrane growth, thereby defining proper apical/lateral membrane ratio that is crucial for forming and maintaining complex epithelial structures such as tubes or acini. Here, we show that Yurt also increases Myosin-dependent cortical tension downstream of Crumbs. Yurt overexpression thus induces apical constriction in epithelial cells. The kinase aPKC phosphorylates Yurt, thereby dislodging the latter from the apical domain and releasing apical tension. In contrast, the kinase Pak1 promotes Yurt dephosphorylation through activation of the phosphatase PP2A. The Pak1–PP2A module thus opposes aPKC function and supports Yurt-induced apical constriction. Hence, the complex interplay between Yurt, aPKC, Pak1, and PP2A contributes to the functional plasticity of Crumbs. Overall, our data increase our understanding of how proteins sustaining epithelial cell polarization and Myosin-dependent cell contractility interact with one another to control epithelial tissue architecture.
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Affiliation(s)
- Cornelia Biehler
- Centre de Recherche sur le Cancer, Université Laval, Québec, Canada.,axe oncologie du Centre de Recherche du Centre Hospitalier Universitaire de Québec-UL, Québec, Canada
| | - Katheryn E Rothenberg
- Institute of Biomedical Engineering, University of Toronto, Toronto, Canada.,Ted Rogers Centre for Heart Research, University of Toronto, Toronto, Canada
| | - Alexandra Jette
- Centre de Recherche sur le Cancer, Université Laval, Québec, Canada.,axe oncologie du Centre de Recherche du Centre Hospitalier Universitaire de Québec-UL, Québec, Canada
| | - Helori-Mael Gaude
- Centre de Recherche sur le Cancer, Université Laval, Québec, Canada.,axe oncologie du Centre de Recherche du Centre Hospitalier Universitaire de Québec-UL, Québec, Canada
| | - Rodrigo Fernandez-Gonzalez
- Institute of Biomedical Engineering, University of Toronto, Toronto, Canada.,Ted Rogers Centre for Heart Research, University of Toronto, Toronto, Canada.,Department of Cell and Systems Biology, University of Toronto, Toronto, Canada.,Developmental and Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Canada
| | - Patrick Laprise
- Centre de Recherche sur le Cancer, Université Laval, Québec, Canada.,axe oncologie du Centre de Recherche du Centre Hospitalier Universitaire de Québec-UL, Québec, Canada
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21
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Holcomb MC, Gao GJJ, Servati M, Schneider D, McNeely PK, Thomas JH, Blawzdziewicz J. Mechanical feedback and robustness of apical constrictions in Drosophila embryo ventral furrow formation. PLoS Comput Biol 2021; 17:e1009173. [PMID: 34228708 PMCID: PMC8284804 DOI: 10.1371/journal.pcbi.1009173] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 07/16/2021] [Accepted: 06/10/2021] [Indexed: 11/19/2022] Open
Abstract
Formation of the ventral furrow in the Drosophila embryo relies on the apical constriction of cells in the ventral region to produce bending forces that drive tissue invagination. In our recent paper we observed that apical constrictions during the initial phase of ventral furrow formation produce elongated patterns of cellular constriction chains prior to invagination and argued that these are indicative of tensile stress feedback. Here, we quantitatively analyze the constriction patterns preceding ventral furrow formation and find that they are consistent with the predictions of our active-granular-fluid model of a monolayer of mechanically coupled stress-sensitive constricting particles. Our model shows that tensile feedback causes constriction chains to develop along underlying precursor tensile stress chains that gradually strengthen with subsequent cellular constrictions. As seen in both our model and available optogenetic experiments, this mechanism allows constriction chains to penetrate or circumvent zones of reduced cell contractility, thus increasing the robustness of ventral furrow formation to spatial variation of cell contractility by rescuing cellular constrictions in the disrupted regions.
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Affiliation(s)
- Michael C. Holcomb
- Department of Physics and Astronomy, Texas Tech University, Lubbock, Texas, United States of America
| | - Guo-Jie Jason Gao
- Department of Mathematical and Systems Engineering, Shizuoka University, Hamamatsu, Japan
| | - Mahsa Servati
- Department of Physics and Astronomy, Texas Tech University, Lubbock, Texas, United States of America
| | - Dylan Schneider
- Department of Mechanical Engineering, Texas Tech University, Lubbock, Texas, United States of America
| | - Presley K. McNeely
- Department of Physics and Astronomy, Texas Tech University, Lubbock, Texas, United States of America
| | - Jeffrey H. Thomas
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, Texas, United States of America
| | - Jerzy Blawzdziewicz
- Department of Physics and Astronomy, Texas Tech University, Lubbock, Texas, United States of America
- Department of Mechanical Engineering, Texas Tech University, Lubbock, Texas, United States of America
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22
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Rice C, De O, Alhadyian H, Hall S, Ward RE. Expanding the Junction: New Insights into Non-Occluding Roles for Septate Junction Proteins during Development. J Dev Biol 2021; 9:11. [PMID: 33801162 PMCID: PMC8006247 DOI: 10.3390/jdb9010011] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 03/15/2021] [Accepted: 03/17/2021] [Indexed: 12/17/2022] Open
Abstract
The septate junction (SJ) provides an occluding function for epithelial tissues in invertebrate organisms. This ability to seal the paracellular route between cells allows internal tissues to create unique compartments for organ function and endows the epidermis with a barrier function to restrict the passage of pathogens. Over the past twenty-five years, numerous investigators have identified more than 30 proteins that are required for the formation or maintenance of the SJs in Drosophila melanogaster, and have determined many of the steps involved in the biogenesis of the junction. Along the way, it has become clear that SJ proteins are also required for a number of developmental events that occur throughout the life of the organism. Many of these developmental events occur prior to the formation of the occluding junction, suggesting that SJ proteins possess non-occluding functions. In this review, we will describe the composition of SJs, taking note of which proteins are core components of the junction versus resident or accessory proteins, and the steps involved in the biogenesis of the junction. We will then elaborate on the functions that core SJ proteins likely play outside of their role in forming the occluding junction and describe studies that provide some cell biological perspectives that are beginning to provide mechanistic understanding of how these proteins function in developmental contexts.
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Affiliation(s)
- Clinton Rice
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045, USA; (C.R.); (H.A.)
| | - Oindrila De
- Department of Biology, Case Western Reserve University, Cleveland, OH 44106, USA;
| | - Haifa Alhadyian
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045, USA; (C.R.); (H.A.)
| | | | - Robert E. Ward
- Department of Biology, Case Western Reserve University, Cleveland, OH 44106, USA;
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Identifying Key Genetic Regions for Cell Sheet Morphogenesis on Chromosome 2L Using a Drosophila Deficiency Screen in Dorsal Closure. G3-GENES GENOMES GENETICS 2020; 10:4249-4269. [PMID: 32978263 PMCID: PMC7642946 DOI: 10.1534/g3.120.401386] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Cell sheet morphogenesis is essential for metazoan development and homeostasis of animal form - it contributes to developmental milestones including gastrulation, neural tube closure, heart and palate formation and to tissue maintenance during wound healing. Dorsal closure, a well-characterized stage in Drosophila embryogenesis and a model for cell sheet morphogenesis, is a remarkably robust process during which coordination of conserved gene expression patterns and signaling cascades regulate the cellular shape changes and movements. New 'dorsal closure genes' continue to be discovered due to advances in imaging and genetics. Here, we extend our previous study of the right arm of the 2nd chromosome to the left arm of the 2nd chromosome using the Bloomington deficiency kit's set of large deletions, which collectively remove 98.9% of the genes on the left arm of chromosome two (2L) to identify 'dorsal closure deficiencies'. We successfully screened 87.2% of the genes and identified diverse dorsal closure defects in embryos homozygous for 49 deficiencies, 27 of which delete no known dorsal closure gene. These homozygous deficiencies cause defects in cell shape, canthus formation and tissue dynamics. Within these deficiencies, we have identified pimples, odd-skipped, paired, and sloppy-paired 1 as dorsal closure genes on 2L that affect lateral epidermal cells. We will continue to identify novel 'dorsal closure genes' with further analysis. These forward genetic screens are expected to identify new processes and pathways that contribute to closure and links between pathways and structures already known to coordinate various aspects of closure.
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24
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Edwards-Jorquera SS, Bosveld F, Bellaïche YA, Lennon-Duménil AM, Glavic Á. Trpml controls actomyosin contractility and couples migration to phagocytosis in fly macrophages. J Cell Biol 2020; 219:133603. [PMID: 31940424 PMCID: PMC7055000 DOI: 10.1083/jcb.201905228] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 11/13/2019] [Accepted: 12/07/2019] [Indexed: 12/29/2022] Open
Abstract
Phagocytes use their actomyosin cytoskeleton to migrate as well as to probe their environment by phagocytosis or macropinocytosis. Although migration and extracellular material uptake have been shown to be coupled in some immune cells, the mechanisms involved in such coupling are largely unknown. By combining time-lapse imaging with genetics, we here identify the lysosomal Ca2+ channel Trpml as an essential player in the coupling of cell locomotion and phagocytosis in hemocytes, the Drosophila macrophage-like immune cells. Trpml is needed for both hemocyte migration and phagocytic processing at distinct subcellular localizations: Trpml regulates hemocyte migration by controlling actomyosin contractility at the cell rear, whereas its role in phagocytic processing lies near the phagocytic cup in a myosin-independent fashion. We further highlight that Vamp7 also regulates phagocytic processing and locomotion but uses pathways distinct from those of Trpml. Our results suggest that multiple mechanisms may have emerged during evolution to couple phagocytic processing to cell migration and facilitate space exploration by immune cells.
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Affiliation(s)
| | - Floris Bosveld
- Institut Curie, PSL Research University, Sorbonne Universités, UPMC Univ Paris 06, Centre National de la Recherche Scientifique UMR 3215, Institut National de la Santé et de la Recherche Médicale U934, Paris, France
| | - Yohanns A Bellaïche
- Institut Curie, PSL Research University, Sorbonne Universités, UPMC Univ Paris 06, Centre National de la Recherche Scientifique UMR 3215, Institut National de la Santé et de la Recherche Médicale U934, Paris, France
| | - Ana-María Lennon-Duménil
- Institut Curie, PSL Research University, Institut National de la Santé et de la Recherche Médicale U932 Immunité et Cancer, Paris, France
| | - Álvaro Glavic
- Centro de Regulación del Genoma, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
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25
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Gubieda AG, Packer JR, Squires I, Martin J, Rodriguez J. Going with the flow: insights from Caenorhabditis elegans zygote polarization. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190555. [PMID: 32829680 PMCID: PMC7482210 DOI: 10.1098/rstb.2019.0555] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/09/2020] [Indexed: 12/12/2022] Open
Abstract
Cell polarity is the asymmetric distribution of cellular components along a defined axis. Polarity relies on complex signalling networks between conserved patterning proteins, including the PAR (partitioning defective) proteins, which become segregated in response to upstream symmetry breaking cues. Although the mechanisms that drive the asymmetric localization of these proteins are dependent upon cell type and context, in many cases the regulation of actomyosin cytoskeleton dynamics is central to the transport, recruitment and/or stabilization of these polarity effectors into defined subcellular domains. The transport or advection of PAR proteins by an actomyosin flow was first observed in the Caenorhabditis elegans zygote more than a decade ago. Since then a multifaceted approach, using molecular methods, high-throughput screens, and biophysical and computational models, has revealed further aspects of this flow and how polarity regulators respond to and modulate it. Here, we review recent findings on the interplay between actomyosin flow and the PAR patterning networks in the polarization of the C. elegans zygote. We also discuss how these discoveries and developed methods are shaping our understanding of other flow-dependent polarizing systems. This article is part of a discussion meeting issue 'Contemporary morphogenesis'.
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Affiliation(s)
| | | | | | | | - Josana Rodriguez
- Biosciences Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
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26
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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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27
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Ozdowski EF, Wentzell JS, Engert SM, Abbott H, Sherwood NT. Suppression of spastin Mutant Phenotypes by Pak3 Loss Implicates a Role for Reactive Glia in AD-HSP. Front Neurosci 2020; 14:912. [PMID: 33013303 PMCID: PMC7499821 DOI: 10.3389/fnins.2020.00912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 08/06/2020] [Indexed: 11/13/2022] Open
Abstract
Neurodegenerative mechanisms due to mutations in spastin currently center on neuronal defects, primarily in microtubule and endomembrane regulation. Spastin loss in Drosophila larvae compromises neuronal microtubule distribution, alters synaptic bouton morphology, and weakens synaptic transmission at glutamatergic neuromuscular junction (NMJ) synapses. Pak3, a p21-activated kinase that promotes actin polymerization and filopodial projections, is required for these spastin mutant defects; animals lacking both genes have normal NMJs. Here we show that Pak3 is expressed in central and peripheral glial populations, and reduction of Pak3 specifically in subperineurial glial cells is sufficient to suppress the phenotypes associated with spastin loss. Subperineurial glia in the periphery ensheathe motor neuron axons and have been shown to extend actin-based projections that regulate synaptic terminals during normal NMJ development. We find that these subperineurial glial projections are Pak3-dependent and nearly twice as frequent in spastin mutants, while in Pak3, spastin double mutants, neither glial projections nor synaptic defects are observed. Spastin deficiency thus increases Pak3-dependent subperineurial glia activity, which is in turn required for neuronal defects. Our results demonstrate a central role for Pak3-mediated, altered glial behavior in the neuronal defects due to spastin loss, and suggest that a similar reactive glia-mediated mechanism may underlie human AD-HSP pathogenesis.
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Affiliation(s)
| | | | | | | | - Nina T. Sherwood
- Department of Biology, Duke University, Durham, NC, United States
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28
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Miao H, Blankenship JT. The pulse of morphogenesis: actomyosin dynamics and regulation in epithelia. Development 2020; 147:dev186502. [PMID: 32878903 PMCID: PMC7490518 DOI: 10.1242/dev.186502] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Actomyosin networks are some of the most crucial force-generating components present in developing tissues. The contractile forces generated by these networks are harnessed during morphogenesis to drive various cell and tissue reshaping events. Recent studies of these processes have advanced rapidly, providing us with insights into how these networks are initiated, positioned and regulated, and how they act via individual contractile pulses and/or the formation of supracellular cables. Here, we review these studies and discuss the mechanisms that underlie the construction and turnover of such networks and structures. Furthermore, we provide an overview of how ratcheted processivity emerges from pulsed events, and how tissue-level mechanics are the coordinated output of many individual cellular behaviors.
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Affiliation(s)
- Hui Miao
- Department of Biological Sciences, Molecular and Cellular Biophysics Program, University of Denver, Denver, CO 80208, USA
| | - J Todd Blankenship
- Department of Biological Sciences, Molecular and Cellular Biophysics Program, University of Denver, Denver, CO 80208, USA
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29
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Periodic Oscillations of Myosin-II Mechanically Proofread Cell-Cell Connections to Ensure Robust Formation of the Cardiac Vessel. Curr Biol 2020; 30:3364-3377.e4. [DOI: 10.1016/j.cub.2020.06.041] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 05/14/2020] [Accepted: 06/12/2020] [Indexed: 01/08/2023]
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30
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Wei Q, Young J, Holle A, Li J, Bieback K, Inman G, Spatz JP, Cavalcanti-Adam EA. Soft Hydrogels for Balancing Cell Proliferation and Differentiation. ACS Biomater Sci Eng 2020; 6:4687-4701. [PMID: 33455192 DOI: 10.1021/acsbiomaterials.0c00854] [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
Hydrogels have been widely explored for the delivery of cells in a variety of regenerative medicine applications due to their ability to mimic both the biochemical and physical cues of cell microniches. For bone regeneration, in particular, stiff hydrogels mimicking osteoid stiffness have been utilized due to the fact that stiff substrates favor stem cell osteogenic differentiation. Unlike cell adhesion in two dimensions, three-dimensional hydrogels offer mechanical stimulation but limit the cell spreading and growth due to the dense matrix network. Therefore, we designed degradable, soft hydrogels (∼0.5 kPa) mimicking the soft bone marrow stiffness, with incorporated matrix metalloproteinase (MMP)-cleavable sites and RGD-based adhesive sites, to enhance the spreading and proliferation of the encapsulated cells, which are commonly inhibited in nondegradable and/or stiff implants. When the hydrogels were cultured on rigid surfaces to mirror the microenvironment of bone defects in vivo, the cells were shown to migrate toward the interface and differentiate down the osteogenic lineage, enhanced by the codelivery of bone morphogenetic protein-2 (BMP-2). Furthermore, this soft hydrogel might find applications in therapeutic interventions since it is easily injectable and cost-efficient. Taken together, we have designed a new system to balance cell growth and differentiation for improving hydrogel-based bone regenerative medicine strategies.
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Affiliation(s)
- Qiang Wei
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials and Engineering, Sichuan University, 610065 Chengdu, China
- Department of Cellular Biophysics, Max Planck Institute for Medical Research, Jahnstraße 29, 69120 Heidelberg, Germany
- Department of Biophysical Chemistry, Heidelberg University, INF 253, 69120 Heidelberg, Germany
| | - Jennifer Young
- Department of Cellular Biophysics, Max Planck Institute for Medical Research, Jahnstraße 29, 69120 Heidelberg, Germany
- Department of Biophysical Chemistry, Heidelberg University, INF 253, 69120 Heidelberg, Germany
| | - Andrew Holle
- Department of Cellular Biophysics, Max Planck Institute for Medical Research, Jahnstraße 29, 69120 Heidelberg, Germany
- Department of Biophysical Chemistry, Heidelberg University, INF 253, 69120 Heidelberg, Germany
| | - Jie Li
- Department of Cellular Biophysics, Max Planck Institute for Medical Research, Jahnstraße 29, 69120 Heidelberg, Germany
- Department of Biophysical Chemistry, Heidelberg University, INF 253, 69120 Heidelberg, Germany
| | - Karen Bieback
- Institute of Transfusion Medicine and Immunology, Medical Faculty Mannheim, Heidelberg University and German Red Cross Blood Service Baden-Württemberg-Hessen, 68167 Mannheim, Germany
| | - Gareth Inman
- Cancer Research UK, Beatson Institute, Garscube Estate, Switchback Road, Glasgow G61 1BD, U.K
- Institute of Cancer Sciences, University of Glasgow, Glasgow G61 1QH, U.K
| | - Joachim P Spatz
- Department of Cellular Biophysics, Max Planck Institute for Medical Research, Jahnstraße 29, 69120 Heidelberg, Germany
- Department of Biophysical Chemistry, Heidelberg University, INF 253, 69120 Heidelberg, Germany
| | - Elisabetta A Cavalcanti-Adam
- Department of Cellular Biophysics, Max Planck Institute for Medical Research, Jahnstraße 29, 69120 Heidelberg, Germany
- Department of Biophysical Chemistry, Heidelberg University, INF 253, 69120 Heidelberg, Germany
- Central Scientific Facility "Cellular Biotechnology", MPI for Medical Research, Jahnstr. 29, 69120 Heidelberg, Germany
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31
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Herrera-Perez RM, Kasza KE. Manipulating the Patterns of Mechanical Forces That Shape Multicellular Tissues. Physiology (Bethesda) 2020; 34:381-391. [PMID: 31577169 DOI: 10.1152/physiol.00018.2019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
During embryonic development, spatial and temporal patterns of mechanical forces help to transform unstructured groups of cells into complex, functional tissue architectures. Here, we review emerging approaches to manipulate these patterns of forces to investigate the mechanical mechanisms that shape multicellular tissues, with a focus on recent experimental studies of epithelial tissue sheets in the embryo of the model organism Drosophila melanogaster.
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Affiliation(s)
| | - Karen E Kasza
- Department of Mechanical Engineering, Columbia University, New York, New York
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32
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Santa-Cruz Mateos C, Valencia-Expósito A, Palacios IM, Martín-Bermudo MD. Integrins regulate epithelial cell shape by controlling the architecture and mechanical properties of basal actomyosin networks. PLoS Genet 2020; 16:e1008717. [PMID: 32479493 PMCID: PMC7263567 DOI: 10.1371/journal.pgen.1008717] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 03/16/2020] [Indexed: 01/01/2023] Open
Abstract
Forces generated by the actomyosin cytoskeleton are key contributors to many morphogenetic processes. The actomyosin cytoskeleton organises in different types of networks depending on intracellular signals and on cell-cell and cell-extracellular matrix (ECM) interactions. However, actomyosin networks are not static and transitions between them have been proposed to drive morphogenesis. Still, little is known about the mechanisms that regulate the dynamics of actomyosin networks during morphogenesis. This work uses the Drosophila follicular epithelium, real-time imaging, laser ablation and quantitative analysis to study the role of integrins on the regulation of basal actomyosin networks organisation and dynamics and the potential contribution of this role to cell shape. We find that elimination of integrins from follicle cells impairs F-actin recruitment to basal medial actomyosin stress fibers. The available F-actin redistributes to the so-called whip-like structures, present at tricellular junctions, and into a new type of actin-rich protrusions that emanate from the basal cortex and project towards the medial region. These F-actin protrusions are dynamic and changes in total protrusion area correlate with periodic cycles of basal myosin accumulation and constriction pulses of the cell membrane. Finally, we find that follicle cells lacking integrin function show increased membrane tension and reduced basal surface. Furthermore, the actin-rich protrusions are responsible for these phenotypes as their elimination in integrin mutant follicle cells rescues both tension and basal surface defects. We thus propose that the role of integrins as regulators of stress fibers plays a key role on controlling epithelial cell shape, as integrin disruption promotes reorganisation into other types of actomyosin networks, in a manner that interferes with proper expansion of epithelial basal surfaces. Morphogenesis involves global changes in tissue architecture driven by cell shape changes. Mechanical forces generated by actomyosin networks and force transmission through adhesive complexes power these changes. The actomyosin cytoskeleton organises in different types of networks, which localise to precise regions and perform distinct roles. However, they are rarely independent and, often, reorganisation of a given structure can promote the formation of another, conversions proposed to underlie many morphogenetic processes. Nonetheless, the mechanisms controlling actomyosin network dynamics during morphogenesis remain poorly characterised. Here, using the Drosophila follicular epithelium, we show that cell-ECM interactions mediated by integrins are required for the correct distribution of actin in the different actin networks. Elimination of integrins results in redistribution of actin from stress fibers into a new type of protrusions that dynamically emanate from the cortex and extend into the stress fibers. Changes in area protrusions correlate with bursts of myosin accumulated in stress fibers and constriction pulses of the cell membrane. We also found that integrin mutant cells show increased membrane tension and reduced basal cell surface. As these defects are rescued by eliminating the F-actin protrusions, we believe these structures prevent proper basal surface growth. Thus, we propose that integrin function as regulators of stress fibers assembly and maintenance controls epithelial cell shape, as its disruption promotes reorganisation into other actomyosin networks, conversions that interfere with proper epithelial basal surface expansion.
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Affiliation(s)
- Carmen Santa-Cruz Mateos
- Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide/CSIC/JA, Carretera de Utrera,Sevilla, Spain
| | - Andrea Valencia-Expósito
- Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide/CSIC/JA, Carretera de Utrera,Sevilla, Spain
| | - Isabel M. Palacios
- School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom
| | - María D. Martín-Bermudo
- Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide/CSIC/JA, Carretera de Utrera,Sevilla, Spain
- * E-mail:
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33
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Martin AC. The Physical Mechanisms of Drosophila Gastrulation: Mesoderm and Endoderm Invagination. Genetics 2020; 214:543-560. [PMID: 32132154 PMCID: PMC7054018 DOI: 10.1534/genetics.119.301292] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 11/21/2019] [Indexed: 12/14/2022] Open
Abstract
A critical juncture in early development is the partitioning of cells that will adopt different fates into three germ layers: the ectoderm, the mesoderm, and the endoderm. This step is achieved through the internalization of specified cells from the outermost surface layer, through a process called gastrulation. In Drosophila, gastrulation is achieved through cell shape changes (i.e., apical constriction) that change tissue curvature and lead to the folding of a surface epithelium. Folding of embryonic tissue results in mesoderm and endoderm invagination, not as individual cells, but as collective tissue units. The tractability of Drosophila as a model system is best exemplified by how much we know about Drosophila gastrulation, from the signals that pattern the embryo to the molecular components that generate force, and how these components are organized to promote cell and tissue shape changes. For mesoderm invagination, graded signaling by the morphogen, Spätzle, sets up a gradient in transcriptional activity that leads to the expression of a secreted ligand (Folded gastrulation) and a transmembrane protein (T48). Together with the GPCR Mist, which is expressed in the mesoderm, and the GPCR Smog, which is expressed uniformly, these signals activate heterotrimeric G-protein and small Rho-family G-protein signaling to promote apical contractility and changes in cell and tissue shape. A notable feature of this signaling pathway is its intricate organization in both space and time. At the cellular level, signaling components and the cytoskeleton exhibit striking polarity, not only along the apical-basal cell axis, but also within the apical domain. Furthermore, gene expression controls a highly choreographed chain of events, the dynamics of which are critical for primordium invagination; it does not simply throw the cytoskeletal "on" switch. Finally, studies of Drosophila gastrulation have provided insight into how global tissue mechanics and movements are intertwined as multiple tissues simultaneously change shape. Overall, these studies have contributed to the view that cells respond to forces that propagate over great distances, demonstrating that cellular decisions, and, ultimately, tissue shape changes, proceed by integrating cues across an entire embryo.
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Affiliation(s)
- Adam C Martin
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142
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34
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Abstract
Cell and tissue shape changes are the fundamental elements of morphogenesis that drive normal development of embryos into fully functional organisms. This requires a variety of cellular processes including establishment and maintenance of polarity, tissue growth and apoptosis, and cell differentiation, rearrangement, and migration. It is widely appreciated that the cytoskeletal networks play an important role in regulating many of these processes and, in particular, that pulsed actomyosin contractions are a core cellular mechanism driving cell shape changes and cell rearrangement. In this review, we discuss the role of pulsed actomyosin contractions during developmental morphogenesis, advances in our understanding of the mechanisms regulating actomyosin pulsing, and novel techniques to probe the role of pulsed actomyosin processes in
in vivo model systems.
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Affiliation(s)
- Ann Sutherland
- Department of Cell Biology, University of Virginia Health System, Charlottesville, VA, USA
| | - Alyssa Lesko
- Department of Cell Biology, University of Virginia Health System, Charlottesville, VA, USA
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35
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Yang B, Liu H, Bi Y, Cheng C, Li G, Kong P, Zhang L, Shi R, Zhang Y, Zhang R, Cheng X. MYH9 promotes cell metastasis via inducing Angiogenesis and Epithelial Mesenchymal Transition in Esophageal Squamous Cell Carcinoma. Int J Med Sci 2020; 17:2013-2023. [PMID: 32788880 PMCID: PMC7415390 DOI: 10.7150/ijms.46234] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Accepted: 07/10/2020] [Indexed: 12/18/2022] Open
Abstract
Non-muscle myosin heavy chain 9 (MYH9) is one novel low frequency mutated gene identified in esophageal squamous cell carcinoma (ESCC) using next-generation sequencing. However, its clinical relevance, potential function and mechanisms remain elusive. Methods: Genomic sequencing datas from 104 esophageal squamous cell carcinoma (ESCC) cases were screened a series of low frequency mutant genes. MYH9 was selected to further analyze its clinical significance, function and PCR-array was performed to explore its potential mechanism. Results: MHY9 is a low frequency mutant gene with a mutation frequency of 2.88% in ESCC. Immunohistochemical analysis showed that MYH9 expression was significantly higher in ESCC tumor tissues, and the expression levels were associated with lymph node metastasis of ESCC patients. Moreover, we found that MYH9 knock-down led to inhibition of cell migration and invasion. PCR-array showed MYH9 knockdown led to a significant change of genes expression associated with angiogenesis and epithelial-to-mesenchymal transition (EMT). This observation is further confirmed in TCGA database of LUSC (lung squamous cell carcinoma), CESC (cervical squamous cell carcinomas) and HNSC (head and neck squamous cell carcinoma). Conclusions: Collectively, our study identifies a novel role and mechanism of MYH9, highlights a significance of MYH9 as a metastatic biomarker, and offers potential therapeutic targets for ESCC patients harboring MYH9 mutations.
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Affiliation(s)
- Bin Yang
- The Department of Thoracic Surgery (Ⅲ), Shanxi Cancer Hospital, Taiyuan, Shanxi 030013, P.R. China.,Department of Pathology & Shanxi Key Laboratory of Carcinogenesis and Translational Research of Esophageal Cancer, Shanxi Medical University, Taiyuan, Shanxi 030001, P.R. China
| | - Huijuan Liu
- Department of Pathology & Shanxi Key Laboratory of Carcinogenesis and Translational Research of Esophageal Cancer, Shanxi Medical University, Taiyuan, Shanxi 030001, P.R. China
| | - Yanghui Bi
- Department of Pathology & Shanxi Key Laboratory of Carcinogenesis and Translational Research of Esophageal Cancer, Shanxi Medical University, Taiyuan, Shanxi 030001, P.R. China
| | - Caixia Cheng
- Department of Pathology & Shanxi Key Laboratory of Carcinogenesis and Translational Research of Esophageal Cancer, Shanxi Medical University, Taiyuan, Shanxi 030001, P.R. China.,Department of Pathology, The First Hospital, Shanxi Medical University, Taiyuan, Shanxi 030001, P.R. China
| | - Guodong Li
- Department of Otorhinolaryngology, Shanxi Provincial People's Hospital Affiliated to Shanxi Medical University, Taiyuan, Shanxi 030012, P.R. China.,Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital Affiliated to Shandong University, Jinan, Shandong 250000, P.R. China
| | - Pengzhou Kong
- Department of Pathology & Shanxi Key Laboratory of Carcinogenesis and Translational Research of Esophageal Cancer, Shanxi Medical University, Taiyuan, Shanxi 030001, P.R. China
| | - Ling Zhang
- Department of Pathology & Shanxi Key Laboratory of Carcinogenesis and Translational Research of Esophageal Cancer, Shanxi Medical University, Taiyuan, Shanxi 030001, P.R. China
| | - Ruyi Shi
- Department of Pathology & Shanxi Key Laboratory of Carcinogenesis and Translational Research of Esophageal Cancer, Shanxi Medical University, Taiyuan, Shanxi 030001, P.R. China
| | - Yunkui Zhang
- The Department of Thoracic Surgery (Ⅲ), Shanxi Cancer Hospital, Taiyuan, Shanxi 030013, P.R. China
| | - Rongsheng Zhang
- The Department of Thoracic Surgery (Ⅲ), Shanxi Cancer Hospital, Taiyuan, Shanxi 030013, P.R. China
| | - Xiaolong Cheng
- Department of Pathology & Shanxi Key Laboratory of Carcinogenesis and Translational Research of Esophageal Cancer, Shanxi Medical University, Taiyuan, Shanxi 030001, P.R. China
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36
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Noll N, Streichan SJ, Shraiman BI. A variational method for image-based inference of internal stress in epithelial tissues. PHYSICAL REVIEW. X 2020; 10:011072. [PMID: 33767909 PMCID: PMC7989596 DOI: 10.1103/physrevx.10.011072] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Cellular mechanics drives epithelial morphogenesis, the process wherein cells collectively rearrange to produce tissue-scale deformations that determine organismal shape. However, quantitative understanding of tissue mechanics is impaired by the difficulty of direct measurement of stress in-vivo. This difficulty has spurred the development of image-based inference algorithms that estimate stress from snapshots of epithelial geometry. Such methods are challenged by sensitivity to measurement error and thus require accurate geometric segmentation for practical use. We overcome this difficulty by introducing a novel approach - the Variational Method of Stress Inference (VMSI) - which exploits the fundamental duality between stress and geometry at equilibrium of discrete mechanical networks that model confluent cellular layers. We approximate the apical geometry of an epithelial tissue by a 2D tiling with Circular Arc Polygons (CAP) in which arcs represent intercellular interfaces defined by the balance of local line tension and pressure differentials between adjacent cells. The mechanical equilibrium of such networks imposes extensive local constraints on CAP geometry. These constraints provide the foundation of VMSI which, starting with images of epithelial monolayers, simultaneously approximates both tissue geometry and internal forces, subject to the constraint of equilibrium. We find VMSI to be more robust than previous methods. Specifically, the VMSI performance is validated by the comparison of the predicted cellular and mesoscopic scale stress with the measured myosin II patterns during early Drosophila embryogenesis. VMSI prediction of mesoscopic stress tensor correlates at the 80% level with the measured myosin distribution and reveals that most of the myosin activity in that case is involved in a static internal force balance within the epithelial layer. In addition to insight into cell mechanics, this study provides a practical method for non-destructive estimation of stress in live epithelial tissue.
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Affiliation(s)
- Nicholas Noll
- Department of Physics, University of California Santa Barbara
- Biozentrum, University of Basel
- Swiss Institute of Bioinformatics
| | - Sebastian J Streichan
- Department of Physics, University of California Santa Barbara
- Kavli Institute for Theoretical Physics
| | - Boris I Shraiman
- Department of Physics, University of California Santa Barbara
- Kavli Institute for Theoretical Physics
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37
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The cellular and molecular mechanisms that establish the mechanics of Drosophila gastrulation. Curr Top Dev Biol 2020; 136:141-165. [DOI: 10.1016/bs.ctdb.2019.08.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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38
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Interplay between integrins and PI4P5K Sktl is crucial for cell polarization and reepithelialisation during Drosophila wound healing. Sci Rep 2019; 9:16331. [PMID: 31704968 PMCID: PMC6842001 DOI: 10.1038/s41598-019-52743-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Accepted: 10/22/2019] [Indexed: 11/08/2022] Open
Abstract
Phosphatidylinositol(4,5)-bisphosphate [PI(4,5)P2] regulates cell adhesion and actin dynamics during cell migration. PI(4,5)P2 binds various components of the cell adhesion machinery, but how these processes affect migration of the epithelial cell sheet is not well understood. Here, we report that PI(4,5)P2 and Sktl, the kinase that converts PI4P to PI(4,5)P2, are both localized to the rear side of cells during wound healing of the Drosophila larval epidermis. The Sktl localization requires JNK pathway activation and integrins, but not PVR. The sktl knockdown epidermis displays strong defects in would closure, reminiscent of the JNK-depleted epidermis, and shows severe disruption of cell polarity, as determined by myosin II localization. Sktl and βPS integrin colocalize at the rear side of cells forming the trailing edge during wound healing and the two are inter-dependent in that the absence of one severely disrupts the rear localization of the other. These results strongly suggest that the JNK pathway regulates the rear localization of Sktl and integrins and the interplay between Sktl and integrins sets up cell polarity, which is crucial for reepithelialisation during wound healing.
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39
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Yolland L, Burki M, Marcotti S, Luchici A, Kenny FN, Davis JR, Serna-Morales E, Müller J, Sixt M, Davidson A, Wood W, Schumacher LJ, Endres RG, Miodownik M, Stramer BM. Persistent and polarized global actin flow is essential for directionality during cell migration. Nat Cell Biol 2019; 21:1370-1381. [PMID: 31685997 PMCID: PMC7025891 DOI: 10.1038/s41556-019-0411-5] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 09/23/2019] [Indexed: 12/11/2022]
Abstract
Cell migration is hypothesized to involve a cycle of behaviours beginning with leading edge extension. However, recent evidence suggests that the leading edge may be dispensable for migration, raising the question of what actually controls cell directionality. Here, we exploit the embryonic migration of Drosophila macrophages to bridge the different temporal scales of the behaviours controlling motility. This approach reveals that edge fluctuations during random motility are not persistent and are weakly correlated with motion. In contrast, flow of the actin network behind the leading edge is highly persistent. Quantification of actin flow structure during migration reveals a stable organization and asymmetry in the cell-wide flowfield that strongly correlates with cell directionality. This organization is regulated by a gradient of actin network compression and destruction, which is controlled by myosin contraction and cofilin-mediated disassembly. It is this stable actin-flow polarity, which integrates rapid fluctuations of the leading edge, that controls inherent cellular persistence.
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Affiliation(s)
- Lawrence Yolland
- Randall Centre for Cell and Molecular Biophysics, King's College London, London, UK
- Department of Mechanical Engineering, University College London, London, UK
| | - Mubarik Burki
- Randall Centre for Cell and Molecular Biophysics, King's College London, London, UK
| | - Stefania Marcotti
- Randall Centre for Cell and Molecular Biophysics, King's College London, London, UK
| | - Andrei Luchici
- Randall Centre for Cell and Molecular Biophysics, King's College London, London, UK
- Dacian Consulting, London, UK
| | - Fiona N Kenny
- Randall Centre for Cell and Molecular Biophysics, King's College London, London, UK
| | - John Robert Davis
- Randall Centre for Cell and Molecular Biophysics, King's College London, London, UK
- The Francis Crick Institute, London, UK
| | | | - Jan Müller
- Institute of Science and Technology Austria (IST Austria), Am Campus 1, Klosterneuburg, Austria
| | - Michael Sixt
- Institute of Science and Technology Austria (IST Austria), Am Campus 1, Klosterneuburg, Austria
| | - Andrew Davidson
- Centre for Inflammation Research, University of Edinburgh, Edinburgh, UK
| | - Will Wood
- Centre for Inflammation Research, University of Edinburgh, Edinburgh, UK
| | - Linus J Schumacher
- Centre for Regenerative Medicine, University of Edinburgh, Edinburgh, UK
| | - Robert G Endres
- Department of Life Sciences, Centre for Integrative Systems Biology and Bioinformatics, Imperial College London, London, UK
| | - Mark Miodownik
- Department of Mechanical Engineering, University College London, London, UK
| | - Brian M Stramer
- Randall Centre for Cell and Molecular Biophysics, King's College London, London, UK.
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40
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Cellular defects resulting from disease-related myosin II mutations in Drosophila. Proc Natl Acad Sci U S A 2019; 116:22205-22211. [PMID: 31615886 DOI: 10.1073/pnas.1909227116] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
The nonmuscle myosin II motor protein produces forces that are essential to driving the cell movements and cell shape changes that generate tissue structure. Mutations in myosin II that are associated with human diseases are predicted to disrupt critical aspects of myosin function, but the mechanisms that translate altered myosin activity into specific changes in tissue organization and physiology are not well understood. Here we use the Drosophila embryo to model human disease mutations that affect myosin motor activity. Using in vivo imaging and biophysical analysis, we show that engineering human MYH9-related disease mutations into Drosophila myosin II produces motors with altered organization and dynamics that fail to drive rapid cell movements, resulting in defects in epithelial morphogenesis. In embryos that express the Drosophila myosin motor variants R707C or N98K and have reduced levels of wild-type myosin, myosin motors are correctly planar polarized and generate anisotropic contractile tension in the tissue. However, expression of these motor variants is associated with a cellular-scale reduction in the speed of cell intercalation, resulting in a failure to promote full elongation of the body axis. In addition, these myosin motor variants display slowed turnover and aberrant aggregation at the cell cortex, indicating that mutations in the motor domain influence mesoscale properties of myosin organization and dynamics. These results demonstrate that disease-associated mutations in the myosin II motor domain disrupt specific aspects of myosin localization and activity during cell intercalation, linking molecular changes in myosin activity to defects in tissue morphogenesis.
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41
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Lee CW, Kwon YC, Lee Y, Park MY, Choe KM. cdc37 is essential for JNK pathway activation and wound closure in Drosophila. Mol Biol Cell 2019; 30:2651-2658. [PMID: 31483695 PMCID: PMC6761768 DOI: 10.1091/mbc.e18-12-0822] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Wound closure in the Drosophila larval epidermis mainly involves nonproliferative, endocyling epithelial cells. Consequently, it is largely mediated by cell growth and migration. We discovered that both cell growth and migration in Drosophila require the cochaperone-encoding gene cdc37. Larvae lacking cdc37 in the epidermis failed to close wounds, and the cells of the epidermis failed to change cell shape and polarize. Likewise, wound-induced cell growth was significantly reduced, and correlated with a reduction in the size of the cell nucleus. The c-Jun N-terminal kinase (JNK) pathway, which is essential for wound closure, was not typically activated in injured cdc37 knockdown larvae. In addition, JNK, Hep, Mkk4, and Tak1 protein levels were reduced, consistent with previous reports showing that Cdc37 is important for the stability of various client kinases. Protein levels of the integrin β subunit and its wound-induced protein expression were also reduced, reflecting the disruption of JNK activation, which is crucial for expression of integrin β during wound closure. These results are consistent with a role of Cdc37 in maintaining the stability of the JNK pathway kinases, thus mediating cell growth and migration during Drosophila wound healing.
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Affiliation(s)
- Chan-Wool Lee
- Department of Systems Biology, Yonsei University, Seodaemun-gu, Seoul 03722, South Korea
| | - Young-Chang Kwon
- Department of Systems Biology, Yonsei University, Seodaemun-gu, Seoul 03722, South Korea
| | - Youngbin Lee
- Department of Systems Biology, Yonsei University, Seodaemun-gu, Seoul 03722, South Korea
| | - Min-Yoon Park
- Department of Systems Biology, Yonsei University, Seodaemun-gu, Seoul 03722, South Korea
| | - Kwang-Min Choe
- Department of Systems Biology, Yonsei University, Seodaemun-gu, Seoul 03722, South Korea
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42
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Manning LA, Perez-Vale KZ, Schaefer KN, Sewell MT, Peifer M. The Drosophila Afadin and ZO-1 homologues Canoe and Polychaetoid act in parallel to maintain epithelial integrity when challenged by adherens junction remodeling. Mol Biol Cell 2019; 30:1938-1960. [PMID: 31188739 PMCID: PMC6727765 DOI: 10.1091/mbc.e19-04-0209] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
During morphogenesis, cells must change shape and move without disrupting tissue integrity. This requires cell-cell junctions to allow dynamic remodeling while resisting forces generated by the actomyosin cytoskeleton. Multiple proteins play roles in junctional-cytoskeletal linkage, but the mechanisms by which they act remain unclear. Drosophila Canoe maintains adherens junction-cytoskeletal linkage during gastrulation. Canoe's mammalian homologue Afadin plays similar roles in cultured cells, working in parallel with ZO-1 proteins, particularly at multicellular junctions. We take these insights back to the fly embryo, exploring how cells maintain epithelial integrity when challenged by adherens junction remodeling during germband extension and dorsal closure. We found that Canoe helps cells maintain junctional-cytoskeletal linkage when challenged by the junctional remodeling inherent in mitosis, cell intercalation, and neuroblast invagination or by forces generated by the actomyosin cable at the leading edge. However, even in the absence of Canoe, many cells retain epithelial integrity. This is explained by a parallel role played by the ZO-1 homologue Polychaetoid. In embryos lacking both Canoe and Polychaetoid, cell junctions fail early, with multicellular junctions especially sensitive, leading to widespread loss of epithelial integrity. Our data suggest that Canoe and Polychaetoid stabilize Bazooka/Par3 at cell-cell junctions, helping maintain balanced apical contractility and tissue integrity.
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Affiliation(s)
- Lathiena A Manning
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Kia Z Perez-Vale
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Kristina N Schaefer
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Mycah T Sewell
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Mark Peifer
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599.,Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599.,Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
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43
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Blount JR, Meyer DN, Akemann C, Johnson SL, Gurdziel K, Baker TR, Todi SV. Unanchored ubiquitin chains do not lead to marked alterations in gene expression in Drosophila melanogaster. Biol Open 2019; 8:bio.043372. [PMID: 31097444 PMCID: PMC6550069 DOI: 10.1242/bio.043372] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The small protein modifier ubiquitin regulates various aspects of cellular biology through its chemical conjugation onto proteins. Ubiquitination of proteins presents itself in numerous iterations, from a single mono-ubiquitination event to chains of poly-ubiquitin. Ubiquitin chains can be attached onto other proteins or can exist as unanchored species, i.e. free from another protein. Unanchored ubiquitin chains are thought to be deleterious to the cell and rapidly disassembled into mono-ubiquitin. We recently examined the toxicity and utilization of unanchored poly-ubiquitin in Drosophila melanogaster. We found that free poly-ubiquitin species are largely innocuous to flies and that free poly-ubiquitin can be controlled by being degraded by the proteasome or by being conjugated onto another protein as a single unit. Here, to explore whether an organismal defense is mounted against unanchored chains, we conducted RNA-Seq analyses to examine the transcriptomic impact of free poly-ubiquitin in the fly. We found ∼90 transcripts whose expression is altered in the presence of different types of unanchored poly-ubiquitin. The set of genes identified was essentially devoid of ubiquitin-, proteasome-, or autophagy-related components. The seeming absence of a large and multipronged response to unanchored poly-ubiquitin supports the conclusion that these species need not be toxic in vivo and underscores the need to re-examine the role of free ubiquitin chains in the cell. Summary: Our Drosophila studies indicate the lack of a marked, coordinated response towards unanchored poly-ubiquitin in flies, suggesting that untethered ubiquitin chains are not necessarily problematic in intact organisms.
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Affiliation(s)
- Jessica R Blount
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Danielle N Meyer
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Camille Akemann
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Sean L Johnson
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Katherine Gurdziel
- Department of Obstetrics and Gynecology, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Tracie R Baker
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI 48201, USA .,Institute of Environmental Health Sciences, Wayne State University, Detroit, MI 48201, USA
| | - Sokol V Todi
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI 48201, USA .,Department of Neurology, Wayne State University School of Medicine, Detroit, MI 48201, USA
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44
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Das Gupta PT, Narasimha M. Cytoskeletal tension and Bazooka tune interface geometry to ensure fusion fidelity and sheet integrity during dorsal closure. eLife 2019; 8:41091. [PMID: 30995201 PMCID: PMC6469929 DOI: 10.7554/elife.41091] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 04/03/2019] [Indexed: 01/09/2023] Open
Abstract
Epithelial fusion establishes continuity between the separated flanks of epithelial sheets. Despite its importance in creating resilient barriers, the mechanisms that ensure stable continuity and preserve morphological and molecular symmetry upon fusion remain unclear. Using the segmented embryonic epidermis whose flanks fuse during Drosophila dorsal closure, we demonstrate that epidermal flanks modulate cell numbers and geometry of their fusing fronts to achieve fusion fidelity. While fusing flanks become more matched for both parameters before fusion, differences persisting at fusion are corrected by modulating fusing front width within each segment to ensure alignment of segment boundaries. We show that fusing cell interfaces are remodelled from en-face contacts at fusion to an interlocking arrangement after fusion, and demonstrate that changes in interface length and geometry are dependent on the spatiotemporal regulation of cytoskeletal tension and Bazooka/Par3. Our work uncovers genetically constrained and mechanically triggered adaptive mechanisms contributing to fusion fidelity and epithelial continuity.
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Affiliation(s)
- Piyal Taru Das Gupta
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Maithreyi Narasimha
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
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45
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Shellard A, Mayor R. Supracellular migration - beyond collective cell migration. J Cell Sci 2019; 132:132/8/jcs226142. [PMID: 30988138 DOI: 10.1242/jcs.226142] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Collective cell migration is a highly complex process in which groups of cells move together. A fundamental question is how cell ensembles can migrate efficiently. In some cases, the group is no more than a collection of individual cells. In others, the group behaves as a supracellular unit, whereby the cell group could be considered as a giant 'supracell', the concept of which was conceived over a century ago. The development of recent tools has provided considerable evidence that cell collectives are highly cooperative, and their migration can better be understood at the tissue level, rather than at the cell level. In this Review, we will define supracellular migration as a type of collective cell migration that operates at a scale higher than the individual cells. We will discuss key concepts of supracellular migration, review recent evidence of collectives exhibiting supracellular features and argue that many seemingly complex collective movements could be better explained by considering the participating cells as supracellular entities.
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Affiliation(s)
- Adam Shellard
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Roberto Mayor
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
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46
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Rauskolb C, Cervantes E, Madere F, Irvine KD. Organization and function of tension-dependent complexes at adherens junctions. J Cell Sci 2019; 132:jcs.224063. [PMID: 30837288 DOI: 10.1242/jcs.224063] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Accepted: 02/22/2019] [Indexed: 12/17/2022] Open
Abstract
Adherens junctions provide attachments between neighboring epithelial cells and a physical link to the cytoskeleton, which enables them to sense and transmit forces and to initiate biomechanical signaling. Examination of the Ajuba LIM protein Jub in Drosophila embryos revealed that it is recruited to adherens junctions in tissues experiencing high levels of myosin activity, and that the pattern of Jub recruitment varies depending upon how tension is organized. In cells with high junctional myosin, Jub is recruited to puncta near intercellular vertices, which are distinct from Ena-containing puncta, but can overlap Vinc-containing puncta. We identify roles for Jub in modulating tension and cellular organization, which are shared with the cytohesin Step, and the cytohesin adapter Sstn, and show that Jub and Sstn together recruit Step to adherens junctions under tension. Our observations establish Jub as a reporter of tension experienced at adherens junctions, and identify distinct types of tension-dependent and tension-independent junctional complexes. They also identify a role for Jub in mediating a feedback loop that modulates the distribution of tension and cellular organization in epithelia.
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Affiliation(s)
- Cordelia Rauskolb
- Waksman Institute and Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, NJ 08854, USA
| | - Estelle Cervantes
- Waksman Institute and Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, NJ 08854, USA
| | - Ferralita Madere
- Waksman Institute and Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, NJ 08854, USA
| | - Kenneth D Irvine
- Waksman Institute and Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, NJ 08854, USA
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47
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Hunter GL, He L, Perrimon N, Charras G, Giniger E, Baum B. A role for actomyosin contractility in Notch signaling. BMC Biol 2019; 17:12. [PMID: 30744634 PMCID: PMC6369551 DOI: 10.1186/s12915-019-0625-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 01/04/2019] [Indexed: 12/24/2022] Open
Abstract
Background Notch-Delta signaling functions across a wide array of animal systems to break symmetry in a sheet of undifferentiated cells and generate cells with different fates, a process known as lateral inhibition. Unlike many other signaling systems, however, since both the ligand and receptor are transmembrane proteins, the activation of Notch by Delta depends strictly on cell-cell contact. Furthermore, the binding of the ligand to the receptor may not be sufficient to induce signaling, since recent work in cell culture suggests that ligand-induced Notch signaling also requires a mechanical pulling force. This tension exposes a cleavage site in Notch that, when cut, activates signaling. Although it is not known if mechanical tension contributes to signaling in vivo, others have suggested that this is how endocytosis of the receptor-ligand complex contributes to the cleavage and activation of Notch. In a similar way, since Notch-mediated lateral inhibition at a distance in the dorsal thorax of the pupal fly is mediated via actin-rich protrusions, it is possible that cytoskeletal forces generated by networks of filamentous actin and non-muscle myosin during cycles of protrusion extension and retraction also contribute to Notch signaling. Results To test this hypothesis, we carried out a detailed analysis of the role of myosin II-dependent tension in Notch signaling in the developing fly and in cell culture. Using dynamic fluorescence-based reporters of Notch, we found that myosin II is important for signaling in signal sending and receiving cells in both systems—as expected if myosin II-dependent tension across the Notch-Delta complex contributes to Notch activation. While myosin II was found to contribute most to signaling at a distance, it was also required for maximal signaling between adjacent cells that share lateral contacts and for signaling between cells in culture. Conclusions Together these results reveal a previously unappreciated role for non-muscle myosin II contractility in Notch signaling, providing further support for the idea that force contributes to the cleavage and activation of Notch in the context of ligand-dependent signaling, and a new paradigm for actomyosin-based mechanosensation. Electronic supplementary material The online version of this article (10.1186/s12915-019-0625-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ginger L Hunter
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, MD, 20892, USA. .,MRC-LMCB, University College London, London, WC1E6BT, UK. .,Institute for the Physics of Living Systems, University College London, London, WC1E6BT, UK. .,Present Address: Department of Biology, Clarkson University, Potsdam, NY, 13699, USA.
| | - Li He
- Department of Genetics, Harvard Medical School, Howard Hughes Medical Institute, Boston, MA, 02115, USA
| | - Norbert Perrimon
- Department of Genetics, Harvard Medical School, Howard Hughes Medical Institute, Boston, MA, 02115, USA
| | - Guillaume Charras
- London Centre for Nanotechnology, University College London, London, WC1E6BT, UK.,Department of Cell and Developmental Biology, University College London, London, WC1E6BT, UK
| | - Edward Giniger
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, MD, 20892, USA.
| | - Buzz Baum
- MRC-LMCB, University College London, London, WC1E6BT, UK.,Institute for the Physics of Living Systems, University College London, London, WC1E6BT, UK
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48
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Scarpa E, Finet C, Blanchard GB, Sanson B. Actomyosin-Driven Tension at Compartmental Boundaries Orients Cell Division Independently of Cell Geometry In Vivo. Dev Cell 2018; 47:727-740.e6. [PMID: 30503752 PMCID: PMC6302072 DOI: 10.1016/j.devcel.2018.10.029] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 09/07/2018] [Accepted: 10/30/2018] [Indexed: 11/29/2022]
Abstract
Cell shape is known to influence the plane of cell division. In vitro, mechanical constraints can also orient mitoses; however, in vivo it is not clear whether tension can orient the mitotic spindle directly, because tissue-scale forces can change cell shape. During segmentation of the Drosophila embryo, actomyosin is enriched along compartment boundaries forming supracellular cables that keep cells segregated into distinct compartments. Here, we show that these actomyosin cables orient the planar division of boundary cells perpendicular to the boundaries. This bias overrides the influence of cell shape, when cells are mildly elongated. By decreasing actomyosin cable tension with laser ablation or, conversely, ectopically increasing tension with laser wounding, we demonstrate that local tension is necessary and sufficient to orient mitoses in vivo. This involves capture of the spindle pole by the actomyosin cortex. These findings highlight the importance of actomyosin-mediated tension in spindle orientation in vivo.
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Affiliation(s)
- Elena Scarpa
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | - Cédric Finet
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | - Guy B Blanchard
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | - Bénédicte Sanson
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK.
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49
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Sánchez-Corrales YE, Röper K. Alignment of cytoskeletal structures across cell boundaries generates tissue cohesion during organ formation. Curr Opin Cell Biol 2018; 55:104-110. [DOI: 10.1016/j.ceb.2018.07.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 06/20/2018] [Accepted: 07/03/2018] [Indexed: 10/28/2022]
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50
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Agarwal P, Zaidel-Bar R. Principles of Actomyosin Regulation In Vivo. Trends Cell Biol 2018; 29:150-163. [PMID: 30385150 DOI: 10.1016/j.tcb.2018.09.006] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 09/22/2018] [Accepted: 09/25/2018] [Indexed: 12/22/2022]
Abstract
The actomyosin cytoskeleton is responsible for most force-driven processes in cells and tissues. How it assembles into the necessary structures at the right time and place is an important question. Here, we focus on molecular mechanisms of actomyosin regulation recently elucidated in animal models, and highlight several common principles that emerge. The architecture of the actomyosin network - an important determinant of its function - results from actin polymerization, crosslinking and turnover, localized myosin activation, and contractility-driven self-organization. Spatiotemporal regulation is achieved by tissue-specific expression and subcellular localization of Rho GTPase regulators. Subcellular anchor points of actomyosin structures control the outcome of their contraction, and molecular feedback mechanisms dictate whether they are transient, cyclic, or persistent.
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Affiliation(s)
- Priti Agarwal
- Mechanobiology Institute, National University of Singapore, Singapore
| | - Ronen Zaidel-Bar
- Mechanobiology Institute, National University of Singapore, Singapore; Department of Cell and Developmental Biology, Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
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