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Lim SE, Vicente-Munuera P, Mao Y. Forced back into shape: Mechanics of epithelial wound repair. Curr Opin Cell Biol 2024; 87:102324. [PMID: 38290420 DOI: 10.1016/j.ceb.2024.102324] [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: 10/06/2023] [Revised: 12/20/2023] [Accepted: 01/03/2024] [Indexed: 02/01/2024]
Abstract
Wound repair, the closing of a hole, is inherently a physical process that requires the change of shape of materials, in this case, cells and tissues. Not only is efficient and accurate wound repair critical for restoring barrier function and reducing infection, but it is also critical for restoring the complex three-dimensional architecture of an organ. This re-sculpting of tissues requires the complex coordination of cell behaviours in multiple dimensions, in space and time, to ensure that the repaired structure can continue functioning optimally. Recent evidence highlights the importance of cell and tissue mechanics in 2D and 3D to achieve such seamless wound repair.
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Affiliation(s)
- Shu En Lim
- Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK; Institute for the Physics of Living Systems, University College London, Gower Street, London WC1E 6BT, UK
| | - Pablo Vicente-Munuera
- Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK; Institute for the Physics of Living Systems, University College London, Gower Street, London WC1E 6BT, UK
| | - Yanlan Mao
- Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK; Institute for the Physics of Living Systems, University College London, Gower Street, London WC1E 6BT, UK.
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2
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Islam ST, Cheheltani S, Cheng C, Fowler VM. Disease-related non-muscle myosin IIA D1424N rod domain mutation, but not R702C motor domain mutation, disrupts mouse ocular lens fiber cell alignment and hexagonal packing. Cytoskeleton (Hoboken) 2024. [PMID: 38516850 DOI: 10.1002/cm.21853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2024] [Revised: 02/28/2024] [Accepted: 03/01/2024] [Indexed: 03/23/2024]
Abstract
The mouse ocular lens is an excellent vertebrate model system for studying hexagonal cell packing and shape changes during tissue morphogenesis and differentiation. The lens is composed of two types of cells, epithelial and fiber cells. During the initiation of fiber cell differentiation, lens epithelial cells transform from randomly packed cells to hexagonally shaped and packed cells to form meridional row cells. The meridional row cells further differentiate and elongate into newly formed fiber cells that maintain hexagonal cell shape and ordered packing. In other tissues, actomyosin contractility regulates cell hexagonal packing geometry during epithelial tissue morphogenesis. Here, we use the mouse lens as a model to study the effect of two human disease-related non-muscle myosin IIA (NMIIA) mutations on lens cellular organization during fiber cell morphogenesis and differentiation. We studied genetic knock-in heterozygous mice with NMIIA-R702C motor domain or NMIIA-D1424N rod domain mutations. We observed that while one allele of NMIIA-R702C has no impact on lens meridional row epithelial cell shape and packing, one allele of the NMIIA-D1424N mutation can cause localized defects in cell hexagonal packing. Similarly, one allele of NMIIA-R702C motor domain mutation does not affect lens fiber cell organization while the NMIIA-D1424N mutant proteins disrupt fiber cell organization and packing. Our work demonstrates that disease-related NMIIA rod domain mutations (D1424N or E1841K) disrupt mouse lens fiber cell morphogenesis and differentiation.
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Affiliation(s)
- Sadia T Islam
- Department of Biological Sciences, University of Delaware, Newark, Delaware, USA
| | - Sepideh Cheheltani
- Department of Biological Sciences, University of Delaware, Newark, Delaware, USA
| | - Catherine Cheng
- School of Optometry and Vision Science Program, Indiana University, Bloomington, Indiana, USA
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, USA
| | - Velia M Fowler
- Department of Biological Sciences, University of Delaware, Newark, Delaware, USA
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, USA
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3
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Mizoguchi Y, Nakashima K, Sato A, Shindo A. β-adrenergic receptor regulates embryonic epithelial extensibility through actomyosin inhibition. iScience 2023; 26:108469. [PMID: 38213788 PMCID: PMC10783608 DOI: 10.1016/j.isci.2023.108469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 10/30/2023] [Accepted: 11/13/2023] [Indexed: 01/13/2024] Open
Abstract
During morphogenesis, epithelial tissues reshape and expand to cover the body and organs. The molecular mechanisms of this deformability remain elusive. Here, we investigate the role of the β-adrenergic receptor (ADRB) in orchestrating actomyosin contractility, pivotal for epithelial extensibility. Chemical screens on Xenopus laevis embryos pinpointed ADRB2 as a principal regulator. ADRB2 promotes actomyosin relaxation, facilitating apical cell area expansion during body elongation. In contrast, ADRB2 knockdown results in heightened cell contraction, marked by synchronous oscillation of F-actin and myosin, impeding body elongation. ADRB2 mutants with reduced affinity for ligand binding lack the function to induce cellular relaxation, highlighting the ligand's essential roles even in the developing epidermis. Our findings unveil ADRB2's critical contribution to extensibility of the epidermis and subsequent body elongation during development. This study also offers insights into the physiology of mature epithelial organs deformed by the smooth muscle response to the adrenergic autonomic nervous system.
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Affiliation(s)
- Yohei Mizoguchi
- Division of Biological Sciences, Department of Molecular Biology, Nagoya University Graduate School of Science, Nagoya 464-8602, Japan
| | - Kaoru Nakashima
- Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto 860-0811, Japan
| | - Ayato Sato
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Nagoya 464-8601, Japan
| | - Asako Shindo
- Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto 860-0811, Japan
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4
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Islam ST, Cheng C, Parreno J, Fowler VM. Nonmuscle Myosin IIA Regulates the Precise Alignment of Hexagonal Eye Lens Epithelial Cells During Fiber Cell Formation and Differentiation. Invest Ophthalmol Vis Sci 2023; 64:20. [PMID: 37070941 PMCID: PMC10123325 DOI: 10.1167/iovs.64.4.20] [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: 10/21/2022] [Accepted: 03/27/2023] [Indexed: 04/19/2023] Open
Abstract
Purpose Epithelial cells in the equatorial region of the ocular lens undergo a remarkable transition from randomly packed cells into precisely aligned and hexagon-shaped cells organized into meridional rows. We investigated the function of nonmuscle myosin IIA (encoded by Myh9) in regulating equatorial epithelial cell alignment to form meridional rows during secondary fiber cell morphogenesis. Methods We used genetic knock-in mice to study a common human Myh9 mutation, E1841K, in the rod domain. The E1841K mutation disrupts bipolar filament assembly. Lens shape, clarity, and stiffness were evaluated, and Western blots were used to determine the level of normal and mutant myosins. Cryosections and lens whole mounts were stained and imaged by confocal microscopy to investigate cell shape and organization. Results We observed no obvious changes in lens size, shape, and biomechanical properties (stiffness and resilience) between the control and nonmuscle myosin IIA-E1841K mutant mice at 2 months of age. Surprisingly, we found misalignment and disorder of fiber cells in heterozygous and homozygous mutant lenses. Further analysis revealed misshapen equatorial epithelial cells that cause disorientation of the meridional rows before fiber cell differentiation in homozygous mutant lenses. Conclusions Our data indicate that nonmuscle myosin IIA bipolar filament assembly is required for the precise alignment of the meridional rows at the lens equator and that the organization of lens fiber cells depends on the proper patterning of meridional row epithelial cells. These data also suggest that lens fiber cell organization and a hexagonal shape are not required for normal lens size, shape transparency, or biomechanical properties.
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Affiliation(s)
- Sadia T. Islam
- Department of Biological Sciences, University of Delaware, Newark, Delaware, United States
| | - Catherine Cheng
- School of Optometry and Vision Science Program, Indiana University, Bloomington, Indiana, United States
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States
| | - Justin Parreno
- Department of Biological Sciences, University of Delaware, Newark, Delaware, United States
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States
| | - Velia M. Fowler
- Department of Biological Sciences, University of Delaware, Newark, Delaware, United States
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States
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5
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Ray S, Agarwal P, Nitzan A, Nédélec F, Zaidel-Bar R. Actin-capping protein regulates actomyosin contractility to maintain germline architecture in C. elegans. Development 2023; 150:dev201099. [PMID: 36897576 PMCID: PMC10112912 DOI: 10.1242/dev.201099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 02/22/2023] [Indexed: 03/11/2023]
Abstract
Actin dynamics play an important role in tissue morphogenesis, yet the control of actin filament growth takes place at the molecular level. A challenge in the field is to link the molecular function of actin regulators with their physiological function. Here, we report an in vivo role of the actin-capping protein CAP-1 in the Caenorhabditis elegans germline. We show that CAP-1 is associated with actomyosin structures in the cortex and rachis, and its depletion or overexpression led to severe structural defects in the syncytial germline and oocytes. A 60% reduction in the level of CAP-1 caused a twofold increase in F-actin and non-muscle myosin II activity, and laser incision experiments revealed an increase in rachis contractility. Cytosim simulations pointed to increased myosin as the main driver of increased contractility following loss of actin-capping protein. Double depletion of CAP-1 and myosin or Rho kinase demonstrated that the rachis architecture defects associated with CAP-1 depletion require contractility of the rachis actomyosin corset. Thus, we uncovered a physiological role for actin-capping protein in regulating actomyosin contractility to maintain reproductive tissue architecture.
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Affiliation(s)
- Shinjini Ray
- Department of Cell and Developmental Biology, Faculty of Medicine, Tel Aviv University, 6997801 Tel Aviv, Israel
- Graduate Program, Mechanobiology Institute, National University of Singapore,117411, Singapore
| | - Priti Agarwal
- Department of Cell and Developmental Biology, Faculty of Medicine, Tel Aviv University, 6997801 Tel Aviv, Israel
| | - Anat Nitzan
- Department of Cell and Developmental Biology, Faculty of Medicine, Tel Aviv University, 6997801 Tel Aviv, Israel
| | - François Nédélec
- Sainsbury Laboratory, University of Cambridge, 47 Bateman Street, Cambridge CB2 1LR, UK
| | - Ronen Zaidel-Bar
- Department of Cell and Developmental Biology, Faculty of Medicine, Tel Aviv University, 6997801 Tel Aviv, Israel
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6
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Lefebvre MF, Claussen NH, Mitchell NP, Gustafson HJ, Streichan SJ. Geometric control of myosin II orientation during axis elongation. eLife 2023; 12:78787. [PMID: 36715100 PMCID: PMC9940909 DOI: 10.7554/elife.78787] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Accepted: 12/13/2022] [Indexed: 01/31/2023] Open
Abstract
The actomyosin cytoskeleton is a crucial driver of morphogenesis. Yet how the behavior of large-scale cytoskeletal patterns in deforming tissues emerges from the interplay of geometry, genetics, and mechanics remains incompletely understood. Convergent extension in Drosophila melanogaster embryos provides the opportunity to establish a quantitative understanding of the dynamics of anisotropic non-muscle myosin II. Cell-scale analysis of protein localization in fixed embryos suggests that gene expression patterns govern myosin anisotropy via complex rules. However, technical limitations have impeded quantitative and dynamic studies of this process at the whole embryo level, leaving the role of geometry open. Here, we combine in toto live imaging with quantitative analysis of molecular dynamics to characterize the distribution of myosin anisotropy and the corresponding genetic patterning. We found pair rule gene expression continuously deformed, flowing with the tissue frame. In contrast, myosin anisotropy orientation remained approximately static and was only weakly deflected from the stationary dorsal-ventral axis of the embryo. We propose that myosin is recruited by a geometrically defined static source, potentially related to the embryo-scale epithelial tension, and account for transient deflections by cytoskeletal turnover and junction reorientation by flow. With only one parameter, this model quantitatively accounts for the time course of myosin anisotropy orientation in wild-type, twist, and even-skipped embryos, as well as embryos with perturbed egg geometry. Geometric patterning of the cytoskeleton suggests a simple physical strategy to ensure a robust flow and formation of shape.
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Affiliation(s)
- Matthew F Lefebvre
- Department of Physics, University of California, Santa BarbaraSanta BarbaraUnited States
| | - Nikolas H Claussen
- Department of Physics, University of California, Santa BarbaraSanta BarbaraUnited States
| | - Noah P Mitchell
- Department of Physics, University of California, Santa BarbaraSanta BarbaraUnited States
- Kavli Institute for Theoretical Physics, University of California, Santa BarbaraSanta BarbaraUnited States
| | - Hannah J Gustafson
- Department of Physics, University of California, Santa BarbaraSanta BarbaraUnited States
- Biomolecular Science and Engineering, University of California, Santa BarbaraSanta BarbaraUnited States
| | - Sebastian J Streichan
- Department of Physics, University of California, Santa BarbaraSanta BarbaraUnited States
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7
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Sokac AM, Biel N, De Renzis S. Membrane-actin interactions in morphogenesis: Lessons learned from Drosophila cellularization. Semin Cell Dev Biol 2023; 133:107-122. [PMID: 35396167 PMCID: PMC9532467 DOI: 10.1016/j.semcdb.2022.03.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 03/18/2022] [Accepted: 03/21/2022] [Indexed: 01/12/2023]
Abstract
During morphogenesis, changes in the shapes of individual cells are harnessed to mold an entire tissue. These changes in cell shapes require the coupled remodeling of the plasma membrane and underlying actin cytoskeleton. In this review, we highlight cellularization of the Drosophila embryo as a model system to uncover principles of how membrane and actin dynamics are co-regulated in space and time to drive morphogenesis.
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Affiliation(s)
- Anna Marie Sokac
- Department of Cell and Developmental Biology, University of Illinois at Urbana Champaign, Urbana, IL 61801, USA; Graduate Program in Integrative and Molecular Biomedical Sciences, Baylor College of Medicine, Houston, TX 77030, USA.
| | - Natalie Biel
- Department of Cell and Developmental Biology, University of Illinois at Urbana Champaign, Urbana, IL 61801, USA; Graduate Program in Integrative and Molecular Biomedical Sciences, Baylor College of Medicine, Houston, TX 77030, USA
| | - Stefano De Renzis
- European Molecular Biology Laboratory Heidelberg, 69117 Heidelberg, Germany
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8
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Sakakibara S, Abdellatef SA, Yamamoto S, Kamimura M, Nakanishi J. Photoactivatable surfaces resolve the impact of gravity vector on collective cell migratory characteristics. SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS 2023; 24:2206525. [PMID: 37151805 PMCID: PMC10158565 DOI: 10.1080/14686996.2023.2206525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Despite considerable interest in the impact of space travel on human health, the influence of the gravity vector on collective cell migration remains unclear. This is primarily because of the difficulty in inducing collective migration, where cell clusters appear in an inverted position against gravity, without cellular damage. In this study, photoactivatable surfaces were used to overcome this challenge. Photoactivatable surfaces enable the formation of geometry-controlled cellular clusters and the remote induction of cellular migration via photoirradiation, thereby maintaining the cells in the inverted position. Substrate inversion preserved the circularity of cellular clusters compared to cells in the normal upright position, with less leader cell appearance. Furthermore, the inversion of cells against the gravity vector resulted in the remodeling of the cytoskeletal system via the strengthening of external actin bundles. Within the 3D cluster architecture, enhanced accumulation of active myosin was observed in the upper cell-cell junction, with a flattened apical surface. Depending on the gravity vector, attenuating actomyosin activity correlates with an increase in the number of leader cells, indicating the importance of cell contractility in collective migration phenotypes and cytoskeletal remodeling.
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Affiliation(s)
- Shinya Sakakibara
- Research Center for Macromolecules and Biomaterials, National Institute for Materials Science (NIMS), Tsukuba, Japan
- Graduate School of Advanced Engineering, Tokyo University of Science, Tokyo, Japan
| | - Shimaa A. Abdellatef
- Research Center for Macromolecules and Biomaterials, National Institute for Materials Science (NIMS), Tsukuba, Japan
- CONTACT Shimaa A. Abdellatef
| | - Shota Yamamoto
- Research Center for Macromolecules and Biomaterials, National Institute for Materials Science (NIMS), Tsukuba, Japan
| | - Masao Kamimura
- Graduate School of Advanced Engineering, Tokyo University of Science, Tokyo, Japan
| | - Jun Nakanishi
- Research Center for Macromolecules and Biomaterials, National Institute for Materials Science (NIMS), Tsukuba, Japan
- Graduate School of Advanced Engineering, Tokyo University of Science, Tokyo, Japan
- Graduate school of Advanced Science and Engineering, Waseda University, Tokyo, Japan
- Jun Nakanishi Research Center for Macromolecules and Biomaterials, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba305-0044, Japan
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9
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Wen FL. Expansion of ring-shaped supracellular contractile cables induces epithelial sheet folding. Phys Rev E 2022; 106:064403. [PMID: 36671152 DOI: 10.1103/physreve.106.064403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 10/05/2022] [Indexed: 06/17/2023]
Abstract
The folding of epithelial cell sheets is a fundamental process that sculpts developing tissues and organs into their proper shapes required for normal physiological functions. In the absence of detailed biochemical regulations, the epithelial sheet folding may simply proceed through buckling due to mechanical compression arising extrinsically from the surroundings or intrinsically within the sheets. Previous studies hypothesized that the formation of an expanding supracellular actomyosin ring within epithelial sheets could result in compression that ultimately leads to epithelial folding during tracheal development in the Drosophila (fruit fly) embryo. However, the exact mechanism by which the formation of epithelial folds is coordinated by the ring expansion remains unclear. Using a vertex-based mechanical model, here I systematically study the dependence of epithelial fold formation on the physical properties of expanding supracellular contractile rings. The simulations show that depending on the contractile strength, epithelial cell sheets can undergo distinct patterns of folding during ring expansion. The formation of folds in particular is robust against fluctuations in the ring properties such as ring numbers and tensions. These findings provide a systematic view to understand how the expansion of supracellular contractile rings in epithelial sheets mediates epithelial folding morphogenesis.
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Affiliation(s)
- Fu-Lai Wen
- International Center for Wound Repair and Regeneration, National Cheng Kung University, Tainan 70101, Taiwan and RIKEN Center for Biosystems Dynamics Research, Kobe 650-0047, Japan
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10
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Alexandrova A, Lomakina M. How does plasticity of migration help tumor cells to avoid treatment: Cytoskeletal regulators and potential markers. Front Pharmacol 2022; 13:962652. [PMID: 36278174 PMCID: PMC9582651 DOI: 10.3389/fphar.2022.962652] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 09/16/2022] [Indexed: 11/13/2022] Open
Abstract
Tumor shrinkage as a result of antitumor therapy is not the only and sufficient indicator of treatment success. Cancer progression leads to dissemination of tumor cells and formation of metastases - secondary tumor lesions in distant organs. Metastasis is associated with acquisition of mobile phenotype by tumor cells as a result of epithelial-to-mesenchymal transition and further cell migration based on cytoskeleton reorganization. The main mechanisms of individual cell migration are either mesenchymal, which depends on the activity of small GTPase Rac, actin polymerization, formation of adhesions with extracellular matrix and activity of proteolytic enzymes or amoeboid, which is based on the increase in intracellular pressure caused by the enhancement of actin cortex contractility regulated by Rho-ROCK-MLCKII pathway, and does not depend on the formation of adhesive structures with the matrix, nor on the activity of proteases. The ability of tumor cells to switch from one motility mode to another depending on cell context and environmental conditions, termed migratory plasticity, contributes to the efficiency of dissemination and often allows the cells to avoid the applied treatment. The search for new therapeutic targets among cytoskeletal proteins offers an opportunity to directly influence cell migration. For successful treatment it is important to assess the likelihood of migratory plasticity in a particular tumor. Therefore, the search for specific markers that can indicate a high probability of migratory plasticity is very important.
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Lamtyugina A, Qiu Y, Fodor É, Dinner AR, Vaikuntanathan S. Thermodynamic Control of Activity Patterns in Cytoskeletal Networks. PHYSICAL REVIEW LETTERS 2022; 129:128002. [PMID: 36179154 PMCID: PMC10014041 DOI: 10.1103/physrevlett.129.128002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 07/26/2022] [Indexed: 06/16/2023]
Abstract
Biological materials, such as the actin cytoskeleton, exhibit remarkable structural adaptability to various external stimuli by consuming different amounts of energy. In this Letter, we use methods from large deviation theory to identify a thermodynamic control principle for structural transitions in a model cytoskeletal network. Specifically, we demonstrate that biasing the dynamics with respect to the work done by nonequilibrium components effectively renormalizes the interaction strength between such components, which can eventually result in a morphological transition. Our work demonstrates how a thermodynamic quantity can be used to renormalize effective interactions, which in turn can tune structure in a predictable manner, suggesting a thermodynamic principle for the control of cytoskeletal structure and dynamics.
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Affiliation(s)
| | - Yuqing Qiu
- Department of Chemistry, University of Chicago, Chicago, IL 60637
- James Franck Institute, University of Chicago, Chicago, IL 60637
| | - Étienne Fodor
- Department of Physics and Materials Science, University of Luxembourg, L-1511 Luxembourg
| | - Aaron R. Dinner
- Department of Chemistry, University of Chicago, Chicago, IL 60637
- James Franck Institute, University of Chicago, Chicago, IL 60637
| | - Suriyanarayanan Vaikuntanathan
- Department of Chemistry, University of Chicago, Chicago, IL 60637
- James Franck Institute, University of Chicago, Chicago, IL 60637
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Da Costa ADS, Subbiah R, Oh SJ, Jeong H, Na JI, Park K, Choi IS, Shin JH. Fibroblasts Close a Void in Free Space by a Purse-String Mechanism. ACS APPLIED MATERIALS & INTERFACES 2022; 14:40522-40534. [PMID: 36036800 DOI: 10.1021/acsami.2c07952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The mechanism by which stromal cells fill voids in injured tissue remains a fundamental question in regenerative medicine. While it is well-established that fibroblasts fill voids by depositing extracellular matrix (ECM) proteins as they migrate toward the wound site, little is known about their ability to adopt an epithelial-like purse-string behavior. To investigate fibroblast behavior during gap closure, we created an artificial wound with a large void space. We discovered that fibroblasts could form a free-standing bridge over deep microvoids, closing the void via purse-string contraction, a mechanism previously thought to be unique to epithelial wound closure. The findings also revealed that myosin II mediated contractility and intercellular adherent junctions were required for the closure of the fibroblast gap in our fabricated three-dimensional artificial wound. To fulfill their repair function under the specific microenvironmental conditions of wounds, fibroblasts appeared to acquire the structural features of epithelial cells, namely, contractile actin bundles that span over multiple cells along the boundary. These findings shed light on a novel mechanism by which stromal cells bridge the 3D gap during physiological processes such as morphogenesis and wound healing.
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Affiliation(s)
- Avelino Dos Santos Da Costa
- Center for Biomaterials, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
- Division of Bio-Medical Science and Technology, KIST School, University of Science and Technology (UST), Seoul 02792, Republic of Korea
- Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Republic of Korea
| | - Ramesh Subbiah
- Center for Biomaterials, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
- Division of Biomaterials and Biomechanics, Department of Restorative Dentistry, School of Dentistry, Oregon Health and Science University (OHSU), Portland, Oregon 97201, United States
| | - Seung Ja Oh
- Center for Biomaterials, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
- Division of Bio-Medical Science and Technology, KIST School, University of Science and Technology (UST), Seoul 02792, Republic of Korea
| | - Hyuntae Jeong
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Jung-Im Na
- Department of Dermatology, Seoul National University Bundang Hospital, Seongnam 13620, Republic of Korea
| | - Kwideok Park
- Center for Biomaterials, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
- Division of Bio-Medical Science and Technology, KIST School, University of Science and Technology (UST), Seoul 02792, Republic of Korea
| | - In-Suk Choi
- Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Republic of Korea
| | - Jennifer H Shin
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
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13
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Ogita G, Kondo T, Ikawa K, Uemura T, Ishihara S, Sugimura K. Image-based parameter inference for epithelial mechanics. PLoS Comput Biol 2022; 18:e1010209. [PMID: 35737656 PMCID: PMC9223404 DOI: 10.1371/journal.pcbi.1010209] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 05/17/2022] [Indexed: 11/19/2022] Open
Abstract
Measuring mechanical parameters in tissues, such as the elastic modulus of cell-cell junctions, is essential to decipher the mechanical control of morphogenesis. However, their in vivo measurement is technically challenging. Here, we formulated an image-based statistical approach to estimate the mechanical parameters of epithelial cells. Candidate mechanical models are constructed based on force-cell shape correlations obtained from image data. Substitution of the model functions into force-balance equations at the cell vertex leads to an equation with respect to the parameters of the model, by which one can estimate the parameter values using a least-squares method. A test using synthetic data confirmed the accuracy of parameter estimation and model selection. By applying this method to Drosophila epithelial tissues, we found that the magnitude and orientation of feedback between the junction tension and shrinkage, which are determined by the spring constant of the junction, were correlated with the elevation of tension and myosin-II on shrinking junctions during cell rearrangement. Further, this method clarified how alterations in tissue polarity and stretching affect the anisotropy in tension parameters. Thus, our method provides a novel approach to uncovering the mechanisms governing epithelial morphogenesis.
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Affiliation(s)
- Goshi Ogita
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
- Graduate School of Biostudies, Kyoto University, Kyoto, Japan
| | - Takefumi Kondo
- Graduate School of Biostudies, Kyoto University, Kyoto, Japan
| | - Keisuke Ikawa
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
- Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University, Kyoto, Japan
| | - Tadashi Uemura
- Graduate School of Biostudies, Kyoto University, Kyoto, Japan
| | - Shuji Ishihara
- Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
- Universal Biology Institute, The University of Tokyo, Tokyo, Japan
- * E-mail: (SI); (KS)
| | - Kaoru Sugimura
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
- Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University, Kyoto, Japan
- Universal Biology Institute, The University of Tokyo, Tokyo, Japan
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, University of Tokyo, Chiba, Japan
- * E-mail: (SI); (KS)
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14
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Gomes de Almeida P, Rifes P, Martins-Jesus AP, Pinheiro GG, Andrade RP, Thorsteinsdóttir S. Cell–Fibronectin Interactions and Actomyosin Contractility Regulate the Segmentation Clock and Spatio-Temporal Somite Cleft Formation during Chick Embryo Somitogenesis. Cells 2022; 11:cells11132003. [PMID: 35805087 PMCID: PMC9266262 DOI: 10.3390/cells11132003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Revised: 06/15/2022] [Accepted: 06/21/2022] [Indexed: 12/19/2022] Open
Abstract
Fibronectin is essential for somite formation in the vertebrate embryo. Fibronectin matrix assembly starts as cells emerge from the primitive streak and ingress in the unsegmented presomitic mesoderm (PSM). PSM cells undergo cyclic waves of segmentation clock gene expression, followed by Notch-dependent upregulation of meso1 in the rostral PSM which induces somite cleft formation. However, the relevance of the fibronectin matrix for these molecular processes remains unknown. Here, we assessed the role of the PSM fibronectin matrix in the spatio-temporal regulation of chick embryo somitogenesis by perturbing (1) extracellular fibronectin matrix assembly, (2) integrin–fibronectin binding, (3) Rho-associated protein kinase (ROCK) activity and (4) non-muscle myosin II (NM II) function. We found that integrin–fibronectin engagement and NM II activity are required for cell polarization in the nascent somite. All treatments resulted in defective somitic clefts and significantly perturbed meso1 and segmentation clock gene expression in the PSM. Importantly, inhibition of actomyosin-mediated contractility increased the period of hairy1/hes4 oscillations from 90 to 120 min. Together, our work strongly suggests that the fibronectin–integrin–ROCK–NM II axis regulates segmentation clock dynamics and dictates the spatio-temporal localization of somitic clefts.
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Affiliation(s)
- Patrícia Gomes de Almeida
- cE3c—CHANGE, Departmento de Biologia Animal, Faculdade de Ciências, Universidade de Lisboa, 1740-016 Lisboa, Portugal; (P.G.d.A.); (P.R.); (G.G.P.)
- ABC-RI, Algarve Biomedical Center Research Institute, 8005-139 Faro, Portugal; (A.P.M.-J.); (R.P.A.)
- Faculdade de Medicina e Ciências Biomédicas (FMCB), Universidade do Algarve, Campus de Gambelas, 8005-139 Faro, Portugal
| | - Pedro Rifes
- cE3c—CHANGE, Departmento de Biologia Animal, Faculdade de Ciências, Universidade de Lisboa, 1740-016 Lisboa, Portugal; (P.G.d.A.); (P.R.); (G.G.P.)
| | - Ana P. Martins-Jesus
- ABC-RI, Algarve Biomedical Center Research Institute, 8005-139 Faro, Portugal; (A.P.M.-J.); (R.P.A.)
- Faculdade de Medicina e Ciências Biomédicas (FMCB), Universidade do Algarve, Campus de Gambelas, 8005-139 Faro, Portugal
| | - Gonçalo G. Pinheiro
- cE3c—CHANGE, Departmento de Biologia Animal, Faculdade de Ciências, Universidade de Lisboa, 1740-016 Lisboa, Portugal; (P.G.d.A.); (P.R.); (G.G.P.)
- ABC-RI, Algarve Biomedical Center Research Institute, 8005-139 Faro, Portugal; (A.P.M.-J.); (R.P.A.)
- Faculdade de Medicina e Ciências Biomédicas (FMCB), Universidade do Algarve, Campus de Gambelas, 8005-139 Faro, Portugal
| | - Raquel P. Andrade
- ABC-RI, Algarve Biomedical Center Research Institute, 8005-139 Faro, Portugal; (A.P.M.-J.); (R.P.A.)
- Faculdade de Medicina e Ciências Biomédicas (FMCB), Universidade do Algarve, Campus de Gambelas, 8005-139 Faro, Portugal
- Champalimaud Research Program, Champalimaud Center for the Unknown, 1400-038 Lisboa, Portugal
| | - Sólveig Thorsteinsdóttir
- cE3c—CHANGE, Departmento de Biologia Animal, Faculdade de Ciências, Universidade de Lisboa, 1740-016 Lisboa, Portugal; (P.G.d.A.); (P.R.); (G.G.P.)
- Correspondence:
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15
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Costache V, Prigent Garcia S, Plancke CN, Li J, Begnaud S, Suman SK, Reymann AC, Kim T, Robin FB. Rapid assembly of a polar network architecture drives efficient actomyosin contractility. Cell Rep 2022; 39:110868. [PMID: 35649363 PMCID: PMC9210446 DOI: 10.1016/j.celrep.2022.110868] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 03/13/2022] [Accepted: 05/05/2022] [Indexed: 11/30/2022] Open
Abstract
Actin network architecture and dynamics play a central role in cell contractility and tissue morphogenesis. RhoA-driven pulsed contractions are a generic mode of actomyosin contractility, but the mechanisms underlying how their specific architecture emerges and how this architecture supports the contractile function of the network remain unclear. Here we show that, during pulsed contractions, the actin network is assembled by two subpopulations of formins: a functionally inactive population (recruited) and formins actively participating in actin filament elongation (elongating). We then show that elongating formins assemble a polar actin network, with barbed ends pointing out of the pulse. Numerical simulations demonstrate that this geometry favors rapid network contraction. Our results show that formins convert a local RhoA activity gradient into a polar network architecture, causing efficient network contractility, underlying the key function of kinetic controls in the assembly and mechanics of cortical network architectures. RhoA-driven actomyosin contractility plays a key role in driving cell and tissue contractility during morphogenesis. Tracking individual formins, Costache et al. show that the network assembled downstream of RhoA displays a polar architecture, barbed ends pointing outward, a feature that supports efficient contractility and force transmission during pulsed contractions.
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Affiliation(s)
- Vlad Costache
- Sorbonne Université, CNRS, INSERM, Institut de Biologie Paris-Seine IBPS, Laboratoire de Biologie du Développement, Paris, France
| | - Serena Prigent Garcia
- Sorbonne Université, CNRS, INSERM, Institut de Biologie Paris-Seine IBPS, Laboratoire de Biologie du Développement, Paris, France
| | - Camille N Plancke
- Sorbonne Université, CNRS, INSERM, Institut de Biologie Paris-Seine IBPS, Laboratoire de Biologie du Développement, Paris, France
| | - Jing Li
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
| | - Simon Begnaud
- Sorbonne Université, CNRS, INSERM, Institut de Biologie Paris-Seine IBPS, Laboratoire de Biologie du Développement, Paris, France
| | - Shashi Kumar Suman
- Sorbonne Université, CNRS, INSERM, Institut de Biologie Paris-Seine IBPS, Laboratoire de Biologie du Développement, Paris, France
| | - Anne-Cécile Reymann
- IGBMC, CNRS UMR7104, INSERM U1258, and Université de Strasbourg, Illkirch, France
| | - Taeyoon Kim
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA.
| | - François B Robin
- Sorbonne Université, CNRS, INSERM, Institut de Biologie Paris-Seine IBPS, Laboratoire de Biologie du Développement, Paris, France.
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16
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Liu Y, Hu YJ, Fan WX, Quan X, Xu B, Li SZ. O-GlcNAcylation: The Underestimated Emerging Regulators of Skeletal Muscle Physiology. Cells 2022; 11:cells11111789. [PMID: 35681484 PMCID: PMC9180116 DOI: 10.3390/cells11111789] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 05/13/2022] [Accepted: 05/17/2022] [Indexed: 02/04/2023] Open
Abstract
O-GlcNAcylation is a highly dynamic, reversible and atypical glycosylation that regulates the activity, biological function, stability, sublocation and interaction of target proteins. O-GlcNAcylation receives and coordinates different signal inputs as an intracellular integrator similar to the nutrient sensor and stress receptor, which target multiple substrates with spatio-temporal analysis specifically to maintain cellular homeostasis and normal physiological functions. Our review gives a brief description of O-GlcNAcylation and its only two processing enzymes and HBP flux, which will help to better understand its physiological characteristics of sensing nutrition and environmental cues. This nutritional and stress-sensitive properties of O-GlcNAcylation allow it to participate in the precise regulation of skeletal muscle metabolism. This review discusses the mechanism of O-GlcNAcylation to alleviate metabolic disorders and the controversy about the insulin resistance of skeletal muscle. The level of global O-GlcNAcylation is precisely controlled and maintained in the “optimal zone”, and its abnormal changes is a potential factor in the pathogenesis of cancer, neurodegeneration, diabetes and diabetic complications. Although the essential role of O-GlcNAcylation in skeletal muscle physiology has been widely studied and recognized, it still is underestimated and overlooked. This review highlights the latest progress and potential mechanisms of O-GlcNAcylation in the regulation of skeletal muscle contraction and structural properties.
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Affiliation(s)
| | | | | | | | - Bin Xu
- Correspondence: (B.X.); (S.-Z.L.)
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17
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Matsuda M, Chu CW, Sokol SY. Lmo7 recruits myosin II heavy chain to regulate actomyosin contractility and apical domain size in Xenopus ectoderm. Development 2022; 149:275389. [PMID: 35451459 PMCID: PMC9188752 DOI: 10.1242/dev.200236] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 03/30/2022] [Indexed: 11/20/2022]
Abstract
ABSTRACT
Apical constriction, or a reduction in size of the apical domain, underlies many morphogenetic events during development. Actomyosin complexes play an essential role in apical constriction; however, the detailed analysis of molecular mechanisms is still pending. Here, we show that Lim domain only protein 7 (Lmo7), a multidomain adaptor at apical junctions, promotes apical constriction in the Xenopus superficial ectoderm, whereas apical domain size increases in Lmo7-depleted cells. Lmo7 is primarily localized at apical junctions and promotes the formation of the dense circumferential actomyosin belt. Strikingly, Lmo7 binds non-muscle myosin II (NMII) and recruits it to apical junctions and the apical cortex. This NMII recruitment is essential for Lmo7-mediated apical constriction. Lmo7 knockdown decreases NMIIA localization at apical junctions and delays neural tube closure in Xenopus embryos. Our findings suggest that Lmo7 serves as a scaffold that regulates actomyosin contractility and apical domain size.
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Affiliation(s)
- Miho Matsuda
- Department of Cell, Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Chih-Wen Chu
- Department of Cell, Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Sergei Y. Sokol
- Department of Cell, Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
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18
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Liu X, Huan P, Liu B. Nonmuscle Myosin II is Required for Larval Shell Formation in a Patellogastropod. Front Cell Dev Biol 2022; 10:813741. [PMID: 35186928 PMCID: PMC8851382 DOI: 10.3389/fcell.2022.813741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 01/11/2022] [Indexed: 11/13/2022] Open
Abstract
The molecular mechanisms underlying larval shell development in mollusks remain largely elusive. We previously found evident filamentous actin (F-actin) aggregations in the developing shell field of the patellogastropod Lottia goshimai, indicating roles of actomyosin networks in the process. In the present study, we functionally characterized nonmuscle myosin II (NM II), the key molecule in actomyosin networks, in the larval shell development of L. goshimai. Immunostaining revealed general colocalization of phosphorylated NM II and F-actin in the shell field. When inhibiting the phosphorylation of NM II using the specific inhibitor blebbistatin in one- or 2-h periods during shell field morphogenesis (6–8 h post-fertilization, hpf), the larval shell plate was completely lost in the veliger larva (24 hpf). Scanning electron microscopy revealed that the nascent larval shell plate could not be developed in the manipulated larvae (10 hpf). Further investigations revealed that key events in shell field morphogenesis were inhibited by blebbistatin pulses, including invagination of the shell field and cell shape changes and cell rearrangements during shell field morphogenesis. These factors caused the changed morphology of the shell field, despite the roughly retained “rosette” organization. To explore whether the specification of related cells was affected by blebbistatin treatments, we investigated the expression of four potential shell formation genes (bmp2/4, gata2/3, hox1 and engrailed). The four genes did not show evident changes in expression level, indicating unaffected cell specification in the shell field, while the gene expression patterns showed variations according to the altered morphology of the shell field. Together, our results reveal that NM II contributes to the morphogenesis of the shell field and is crucial for the formation of the larval shell plate in L. goshimai. These results add to the knowledge of the mechanisms of molluskan shell development.
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Affiliation(s)
- Xinyu Liu
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, China
- Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Pin Huan
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, China
- Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, China
| | - Baozhong Liu
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, China
- Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, China
- University of Chinese Academy of Sciences, Beijing, China
- *Correspondence: Baozhong Liu,
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19
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Abstract
Optogenetics is a powerful technique that allows the control of protein function with high spatiotemporal precision using light. Here, we describe the application of this method to control tissue mechanics during Drosophila embryonic development. We detail optogenetic protocols to either increase or decrease cell contractility and analyze the interplay between cell-cell interaction, tissue geometry, and force transmission during gastrulation.
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Affiliation(s)
- Daniel Krueger
- European Molecular Biology Laboratory (EMBL), Developmental Biology Unit, Heidelberg, Germany
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences (KNAW), Utrecht, The Netherlands
| | - Stefano De Renzis
- European Molecular Biology Laboratory (EMBL), Developmental Biology Unit, Heidelberg, Germany.
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20
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Li Y, Munro E. Filament-guided filament assembly provides structural memory of filament alignment during cytokinesis. Dev Cell 2021; 56:2486-2500.e6. [PMID: 34480876 DOI: 10.1016/j.devcel.2021.08.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 05/30/2021] [Accepted: 08/13/2021] [Indexed: 10/24/2022]
Abstract
During cytokinesis, animal cells rapidly remodel the equatorial cortex to build an aligned array of actin filaments called the contractile ring. Local reorientation of filaments by active equatorial compression is thought to underlie the emergence of filament alignment during ring assembly. Here, combining single molecule analysis and modeling in one-cell C. elegans embryos, we show that filaments turnover is far too fast for reorientation of individual filaments by equatorial compression to explain the observed alignment, even if favorably oriented filaments are selectively stabilized. By tracking single formin/CYK-1::GFP particles to monitor local filament assembly, we identify a mechanism that we call filament-guided filament assembly (FGFA), in which existing filaments serve as templates to orient the growth of new filaments. FGFA sharply increases the effective lifetime of filament orientation, providing structural memory that allows cells to build highly aligned filament arrays in response to equatorial compression, despite rapid turnover of individual filaments.
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Affiliation(s)
- Younan Li
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA
| | - Edwin Munro
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA; Committee on Development, Regeneration and Stem Cell Biology, University of Chicago, Chicago, IL 60637, USA; Institute for Biophysical Dynamics, University of Chicago, Chicago, IL 60637, USA.
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21
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Kollimada S, Senger F, Vignaud T, Théry M, Blanchoin L, Kurzawa L. The biochemical composition of the actomyosin network sets the magnitude of cellular traction forces. Mol Biol Cell 2021; 32:1737-1748. [PMID: 34410837 PMCID: PMC8684728 DOI: 10.1091/mbc.e21-03-0109] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The regulation of cellular force production relies on the complex interplay between a well-conserved set of proteins of the cytoskeleton: actin, myosin, and α-actinin. Despite our deep knowledge of the role of these proteins in force production at the molecular scale, our understanding of the biochemical regulation of the magnitude of traction forces generated at the entire-cell level has been limited, notably by the technical challenge of measuring traction forces and the endogenous biochemical composition in the same cell. In this study, we developed an alternative Traction-Force Microscopy (TFM) assay, which used a combination of hydrogel micropatterning to define cell adhesion and shape and an intermediate fixation/immunolabeling step to characterize strain energies and the endogenous protein contents in single epithelial cells. Our results demonstrated that both the signal intensity and the area of the Focal Adhesion (FA)–associated protein vinculin showed a strong positive correlation with strain energy in mature FAs. Individual contents from actin filament and phospho-myosin displayed broader deviation in their linear relationship to strain energies. Instead, our quantitative analyzes demonstrated that their relative amount exhibited an optimum ratio of phospho-myosin to actin, allowing maximum force production by cells. By contrast, although no correlation was identified between individual α-actinin content and strain energy, the ratio of α-actinin to actin filaments was inversely related to strain energy. Hence, our results suggest that, in the cellular model studied, traction-force magnitude is dictated by the relative numbers of molecular motors and cross-linkers per actin filament, rather than the amounts of an individual component in the cytoskeletal network. This assay offers new perspectives to study in more detail the complex interplay between the endogenous biochemical composition of individual cells and the force they produce.
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Affiliation(s)
- Somanna Kollimada
- Interdisciplinary Research Institute of Grenoble, Laboratoire de Physiologie Cellulaire & Végétale, CytoMorpho Lab, University of Grenoble-Alpes, CEA, CNRS, INRA, Grenoble, France
| | - Fabrice Senger
- Interdisciplinary Research Institute of Grenoble, Laboratoire de Physiologie Cellulaire & Végétale, CytoMorpho Lab, University of Grenoble-Alpes, CEA, CNRS, INRA, Grenoble, France
| | - Timothée Vignaud
- Interdisciplinary Research Institute of Grenoble, Laboratoire de Physiologie Cellulaire & Végétale, CytoMorpho Lab, University of Grenoble-Alpes, CEA, CNRS, INRA, Grenoble, France.,Clinique de chirurgie digestive et endocrinienne, Hôtel Dieu, Nantes, 44093, France
| | - Manuel Théry
- Interdisciplinary Research Institute of Grenoble, Laboratoire de Physiologie Cellulaire & Végétale, CytoMorpho Lab, University of Grenoble-Alpes, CEA, CNRS, INRA, Grenoble, France.,Institut de Recherche Saint Louis, U976 Human Immunology Pathophysiology Immunotherapy (HIPI), CytoMorpho Lab, University of Paris, INSERM, CEA, Paris, France
| | - Laurent Blanchoin
- Interdisciplinary Research Institute of Grenoble, Laboratoire de Physiologie Cellulaire & Végétale, CytoMorpho Lab, University of Grenoble-Alpes, CEA, CNRS, INRA, Grenoble, France.,Institut de Recherche Saint Louis, U976 Human Immunology Pathophysiology Immunotherapy (HIPI), CytoMorpho Lab, University of Paris, INSERM, CEA, Paris, France
| | - Laëtitia Kurzawa
- Interdisciplinary Research Institute of Grenoble, Laboratoire de Physiologie Cellulaire & Végétale, CytoMorpho Lab, University of Grenoble-Alpes, CEA, CNRS, INRA, Grenoble, France
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22
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Inman A, Smutny M. Feeling the force: Multiscale force sensing and transduction at the cell-cell interface. Semin Cell Dev Biol 2021; 120:53-65. [PMID: 34238674 DOI: 10.1016/j.semcdb.2021.06.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 06/11/2021] [Accepted: 06/13/2021] [Indexed: 12/13/2022]
Abstract
A universal principle of all living cells is the ability to sense and respond to mechanical stimuli which is essential for many biological processes. Recent efforts have identified critical mechanosensitive molecules and response pathways involved in mechanotransduction during development and tissue homeostasis. Tissue-wide force transmission and local force sensing need to be spatiotemporally coordinated to precisely regulate essential processes during development such as tissue morphogenesis, patterning, cell migration and organogenesis. Understanding how cells identify and interpret extrinsic forces and integrate a specific response on cell and tissue level remains a major challenge. In this review we consider important cellular and physical factors in control of cell-cell mechanotransduction and discuss their significance for cell and developmental processes. We further highlight mechanosensitive macromolecules that are known to respond to external forces and present examples of how force responses can be integrated into cell and developmental programs.
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Affiliation(s)
- Angus Inman
- Centre for Mechanochemical Cell Biology and Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry CV47AL, UK
| | - Michael Smutny
- Centre for Mechanochemical Cell Biology and Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry CV47AL, UK.
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23
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Nishimura Y, Shi S, Zhang F, Liu R, Takagi Y, Bershadsky AD, Viasnoff V, Sellers JR. The formin inhibitor SMIFH2 inhibits members of the myosin superfamily. J Cell Sci 2021; 134:237818. [PMID: 33589498 PMCID: PMC8121067 DOI: 10.1242/jcs.253708] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 02/03/2021] [Indexed: 12/31/2022] Open
Abstract
The small molecular inhibitor of formin FH2 domains, SMIFH2, is widely used in cell biological studies. It inhibits formin-driven actin polymerization in vitro, but not polymerization of pure actin. It is active against several types of formin from different species. Here, we found that SMIFH2 inhibits retrograde flow of myosin 2 filaments and contraction of stress fibers. We further checked the effect of SMIFH2 on non-muscle myosin 2A and skeletal muscle myosin 2 in vitro, and found that SMIFH2 inhibits activity of myosin ATPase and the ability to translocate actin filaments in the gliding actin in vitro motility assay. Inhibition of non-muscle myosin 2A in vitro required a higher concentration of SMIFH2 compared with that needed to inhibit retrograde flow and stress fiber contraction in cells. We also found that SMIFH2 inhibits several other non-muscle myosin types, including bovine myosin 10, Drosophila myosin 7a and Drosophila myosin 5, more efficiently than it inhibits formins. These off-target inhibitions demand additional careful analysis in each case when solely SMIFH2 is used to probe formin functions. This article has an associated First Person interview with Yukako Nishimura, joint first author of the paper.
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Affiliation(s)
- Yukako Nishimura
- Mechanobiology Institute (MBI), National University of Singapore, Singapore 117411, Singapore
| | - Shidong Shi
- Mechanobiology Institute (MBI), National University of Singapore, Singapore 117411, Singapore
| | - Fang Zhang
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Rong Liu
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yasuharu Takagi
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Alexander D Bershadsky
- Mechanobiology Institute (MBI), National University of Singapore, Singapore 117411, Singapore.,Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Virgile Viasnoff
- Mechanobiology Institute (MBI), National University of Singapore, Singapore 117411, Singapore.,CNRS UMI 3639 BMC, Singapore 117411, Singapore.,Department of Biological Sciences, National university of Singapore, Singapore 117558, Singapore
| | - James R Sellers
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
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24
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Gaston C, De Beco S, Doss B, Pan M, Gauquelin E, D'Alessandro J, Lim CT, Ladoux B, Delacour D. EpCAM promotes endosomal modulation of the cortical RhoA zone for epithelial organization. Nat Commun 2021; 12:2226. [PMID: 33850145 PMCID: PMC8044225 DOI: 10.1038/s41467-021-22482-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Accepted: 03/11/2021] [Indexed: 01/13/2023] Open
Abstract
At the basis of cell shape and behavior, the organization of actomyosin and its ability to generate forces are widely studied. However, the precise regulation of this contractile network in space and time is unclear. Here, we study the role of the epithelial-specific protein EpCAM, a contractility modulator, in cell shape and motility. We show that EpCAM is required for stress fiber generation and front-rear polarity acquisition at the single cell level. In fact, EpCAM participates in the remodeling of a transient zone of active RhoA at the cortex of spreading epithelial cells. EpCAM and RhoA route together through the Rab35/EHD1 fast recycling pathway. This endosomal pathway spatially organizes GTP-RhoA to fine tune the activity of actomyosin resulting in polarized cell shape and development of intracellular stiffness and traction forces. Impairment of GTP-RhoA endosomal trafficking either by silencing EpCAM or by expressing Rab35/EHD1 mutants prevents proper myosin-II activity, stress fiber formation and ultimately cell polarization. Collectively, this work shows that the coupling between co-trafficking of EpCAM and RhoA, and actomyosin rearrangement is pivotal for cell spreading, and advances our understanding of how biochemical and mechanical properties promote cell plasticity.
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Affiliation(s)
- Cécile Gaston
- Cell Adhesion and Mechanics, Institut Jacques Monod, CNRS UMR7592, Paris Diderot University, Paris, France
| | - Simon De Beco
- Cell Adhesion and Mechanics, Institut Jacques Monod, CNRS UMR7592, Paris Diderot University, Paris, France
| | - Bryant Doss
- Mechanobiology Institute, T-lab, Singapore, Singapore
| | - Meng Pan
- Mechanobiology Institute, T-lab, Singapore, Singapore
| | - Estelle Gauquelin
- Cell Adhesion and Mechanics, Institut Jacques Monod, CNRS UMR7592, Paris Diderot University, Paris, France
| | - Joseph D'Alessandro
- Cell Adhesion and Mechanics, Institut Jacques Monod, CNRS UMR7592, Paris Diderot University, Paris, France
| | | | - Benoit Ladoux
- Cell Adhesion and Mechanics, Institut Jacques Monod, CNRS UMR7592, Paris Diderot University, Paris, France
| | - Delphine Delacour
- Cell Adhesion and Mechanics, Institut Jacques Monod, CNRS UMR7592, Paris Diderot University, Paris, France.
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25
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Sharma S, Rikhy R. Spatiotemporal recruitment of RhoGTPase protein GRAF inhibits actomyosin ring constriction in Drosophila cellularization. eLife 2021; 10:63535. [PMID: 33835025 PMCID: PMC8081525 DOI: 10.7554/elife.63535] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 03/31/2021] [Indexed: 11/18/2022] Open
Abstract
Actomyosin contractility is regulated by Rho-GTP in cell migration, cytokinesis and morphogenesis in embryo development. Whereas Rho activation by Rho-GTP exchange factor (GEF), RhoGEF2, is well known in actomyosin contractility during cytokinesis at the base of invaginating membranes in Drosophila cellularization, Rho inhibition by RhoGTPase-activating proteins (GAPs) remains to be studied. We have found that the RhoGAP, GRAF, inhibits actomyosin contractility during cellularization. GRAF is enriched at the cleavage furrow tip during actomyosin assembly and initiation of ring constriction. Graf depletion shows increased Rho-GTP, increased Myosin II and ring hyper constriction dependent upon the loss of the RhoGTPase domain. GRAF and RhoGEF2 are present in a balance for appropriate activation of actomyosin ring constriction. RhoGEF2 depletion and abrogation of Myosin II activation in Rho kinase mutants suppress the Graf hyper constriction defect. Therefore, GRAF recruitment restricts Rho-GTP levels in a spatiotemporal manner for inhibiting actomyosin contractility during cellularization.
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Affiliation(s)
- Swati Sharma
- Biology, Indian Institute of Science Education and Research, Pune, India
| | - Richa Rikhy
- Biology, Indian Institute of Science Education and Research, Pune, India
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26
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Weirich KL, Stam S, Munro E, Gardel ML. Actin bundle architecture and mechanics regulate myosin II force generation. Biophys J 2021; 120:1957-1970. [PMID: 33798565 DOI: 10.1016/j.bpj.2021.03.026] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 03/01/2021] [Accepted: 03/12/2021] [Indexed: 10/21/2022] Open
Abstract
The actin cytoskeleton is a soft, structural material that underlies biological processes such as cell division, motility, and cargo transport. The cross-linked actin filaments self-organize into a myriad of architectures, from disordered meshworks to ordered bundles, which are hypothesized to control the actomyosin force generation that regulates cell migration, shape, and adhesion. Here, we use fluorescence microscopy and simulations to investigate how actin bundle architectures with varying polarity, spacing, and rigidity impact myosin II dynamics and force generation. Microscopy reveals that mixed-polarity bundles formed by rigid cross-linkers support slow, bidirectional myosin II filament motion, punctuated by periods of stalled motion. Simulations reveal that these locations of stalled myosin motion correspond to sustained, high forces in regions of balanced actin filament polarity. By contrast, mixed-polarity bundles formed by compliant, large cross-linkers support fast, bidirectional motion with no traps. Simulations indicate that trap duration is directly related to force magnitude and that the observed increased velocity corresponds to lower forces resulting from both the increased bundle compliance and filament spacing. Our results indicate that the microstructures of actin assemblies regulate the dynamics and magnitude of myosin II forces, highlighting the importance of architecture and mechanics in regulating forces in biological materials.
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Affiliation(s)
- Kimberly L Weirich
- James Franck Institute, University of Chicago, Chicago, Illinois; Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois; Department of Materials Science and Engineering, Clemson University, Clemson, South Carolina
| | - Samantha Stam
- Biophysical Sciences Graduate Program, University of Chicago, Chicago, Illinois; Institute for Biophysical Dynamics, University of Chicago, Chicago, Illinois; Department of Molecular and Cellular Biology, University of California, Davis, Davis, California
| | - Edwin Munro
- Institute for Biophysical Dynamics, University of Chicago, Chicago, Illinois; Department of Molecular Genetics and Cellular Biology, University of Chicago, Chicago, Illinois
| | - Margaret L Gardel
- James Franck Institute, University of Chicago, Chicago, Illinois; Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois; Institute for Biophysical Dynamics, University of Chicago, Chicago, Illinois; Department of Physics, University of Chicago, Chicago, Illinois.
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27
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Nakamura M, Verboon JM, Prentiss CL, Parkhurst SM. The kinesin-like protein Pavarotti functions noncanonically to regulate actin dynamics. J Cell Biol 2021; 219:151940. [PMID: 32673395 PMCID: PMC7480107 DOI: 10.1083/jcb.201912117] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 05/07/2020] [Accepted: 06/09/2020] [Indexed: 01/03/2023] Open
Abstract
Pavarotti, the Drosophila MKLP1 orthologue, is a kinesin-like protein that works with Tumbleweed (MgcRacGAP) as the centralspindlin complex. This complex is essential for cytokinesis, where it helps to organize the contractile actomyosin ring at the equator of dividing cells by activating the RhoGEF Pebble. Actomyosin rings also function as the driving force during cell wound repair. We previously showed that Tumbleweed and Pebble are required for the cell wound repair process. Here, we show that Pavarotti also functions during wound repair and confirm that while Pavarotti, Tumbleweed, and Pebble are all used during this cellular repair, each has a unique localization pattern and knockdown phenotype, demonstrating centralspindlin-independent functions. Surprisingly, we find that the classically microtubule-associated Pavarotti binds directly to actin in vitro and in vivo and has a noncanonical role directly regulating actin dynamics. Finally, we demonstrate that this actin regulation by Pavarotti is not specific to cellular wound repair but is also used in normal development.
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Affiliation(s)
- Mitsutoshi Nakamura
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA
| | - Jeffrey M Verboon
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA
| | - Clara L Prentiss
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA
| | - Susan M Parkhurst
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA
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28
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Du W, Bhojwani A, Hu JK. FACEts of mechanical regulation in the morphogenesis of craniofacial structures. Int J Oral Sci 2021; 13:4. [PMID: 33547271 PMCID: PMC7865003 DOI: 10.1038/s41368-020-00110-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Revised: 12/03/2020] [Accepted: 12/07/2020] [Indexed: 02/07/2023] Open
Abstract
During embryonic development, organs undergo distinct and programmed morphological changes as they develop into their functional forms. While genetics and biochemical signals are well recognized regulators of morphogenesis, mechanical forces and the physical properties of tissues are now emerging as integral parts of this process as well. These physical factors drive coordinated cell movements and reorganizations, shape and size changes, proliferation and differentiation, as well as gene expression changes, and ultimately sculpt any developing structure by guiding correct cellular architectures and compositions. In this review we focus on several craniofacial structures, including the tooth, the mandible, the palate, and the cranium. We discuss the spatiotemporal regulation of different mechanical cues at both the cellular and tissue scales during craniofacial development and examine how tissue mechanics control various aspects of cell biology and signaling to shape a developing craniofacial organ.
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Affiliation(s)
- Wei Du
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China
- School of Dentistry, University of California Los Angeles, Los Angeles, CA, USA
| | - Arshia Bhojwani
- School of Dentistry, University of California Los Angeles, Los Angeles, CA, USA
| | - Jimmy K Hu
- School of Dentistry, University of California Los Angeles, Los Angeles, CA, USA.
- Molecular Biology Institute, University of California Los Angeles, Los Angeles, CA, USA.
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29
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The Actomyosin Cortex of Cells: A Thin Film of Active Matter. J Indian Inst Sci 2021. [DOI: 10.1007/s41745-020-00220-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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30
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Gan WJ, Motegi F. Mechanochemical Control of Symmetry Breaking in the Caenorhabditis elegans Zygote. Front Cell Dev Biol 2021; 8:619869. [PMID: 33537308 PMCID: PMC7848089 DOI: 10.3389/fcell.2020.619869] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 12/08/2020] [Indexed: 12/14/2022] Open
Abstract
Cell polarity is the asymmetric organization of cellular components along defined axes. A key requirement for polarization is the ability of the cell to break symmetry and achieve a spatially biased organization. Despite different triggering cues in various systems, symmetry breaking (SB) usually relies on mechanochemical modulation of the actin cytoskeleton, which allows for advected movement and reorganization of cellular components. Here, the mechanisms underlying SB in Caenorhabditis elegans zygote, one of the most popular models to study cell polarity, are reviewed. A zygote initiates SB through the centrosome, which modulates mechanics of the cell cortex to establish advective flow of cortical proteins including the actin cytoskeleton and partitioning defective (PAR) proteins. The chemical signaling underlying centrosomal control of the Aurora A kinase–mediated cascade to convert the organization of the contractile actomyosin network from an apolar to polar state is also discussed.
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Affiliation(s)
- Wan Jun Gan
- Temasek Life-Sciences Laboratory, Singapore, Singapore
| | - Fumio Motegi
- Temasek Life-Sciences Laboratory, Singapore, Singapore.,Department of Biological Sciences, National University of Singapore, Singapore, Singapore.,Mechanobiology Institute, National University of Singapore, Singapore, Singapore.,Institute of Genetic Medicine, Hokkaido University, Sapporo, Japan
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31
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Vemula V, Huber T, Ušaj M, Bugyi B, Månsson A. Myosin and gelsolin cooperate in actin filament severing and actomyosin motor activity. J Biol Chem 2020; 296:100181. [PMID: 33303625 PMCID: PMC7948409 DOI: 10.1074/jbc.ra120.015863] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 12/05/2020] [Accepted: 12/10/2020] [Indexed: 01/06/2023] Open
Abstract
Actin is a major intracellular protein with key functions in cellular motility, signaling, and structural rearrangements. Its dynamic behavior, such as polymerization and depolymerization of actin filaments in response to intracellular and extracellular cues, is regulated by an abundance of actin binding proteins. Out of these, gelsolin is one of the most potent for filament severing. However, myosin motor activity also fragments actin filaments through motor-induced forces, suggesting that these two proteins could cooperate to regulate filament dynamics and motility. To test this idea, we used an in vitro motility assay, where actin filaments are propelled by surface-adsorbed heavy meromyosin (HMM) motor fragments. This allows studies of both motility and filament dynamics using isolated proteins. Gelsolin, at both nanomolar and micromolar Ca2+ concentration, appreciably enhanced actin filament severing caused by HMM-induced forces at 1 mM MgATP, an effect that was increased at higher HMM motor density. This finding is consistent with cooperativity between actin filament severing by myosin-induced forces and by gelsolin. We also observed reduced sliding velocity of the HMM-propelled filaments in the presence of gelsolin, providing further support of myosin-gelsolin cooperativity. Total internal reflection fluorescence microscopy–based single molecule studies corroborated that the velocity reduction was a direct effect of gelsolin binding to the filament and revealed different filament severing pattern of stationary and HMM propelled filaments. Overall, the results corroborate cooperative effects between gelsolin-induced alterations in the actin filaments and changes due to myosin motor activity leading to enhanced F-actin severing of possible physiological relevance.
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Affiliation(s)
- Venukumar Vemula
- Department of Chemistry and Biomedical Sciences, Linnaeus University, Kalmar, Sweden
| | - Tamás Huber
- Department of Biophysics, Medical School, University of Pécs, Pécs, Hungary
| | - Marko Ušaj
- Department of Chemistry and Biomedical Sciences, Linnaeus University, Kalmar, Sweden
| | - Beáta Bugyi
- Department of Biophysics, Medical School, University of Pécs, Pécs, Hungary.
| | - Alf Månsson
- Department of Chemistry and Biomedical Sciences, Linnaeus University, Kalmar, Sweden.
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32
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Sui L, Dahmann C. Increased lateral tension is sufficient for epithelial folding in Drosophila. Development 2020; 147:147/23/dev194316. [DOI: 10.1242/dev.194316] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 10/16/2020] [Indexed: 11/20/2022]
Abstract
ABSTRACT
The folding of epithelial sheets is important for tissues, organs and embryos to attain their proper shapes. Epithelial folding requires subcellular modulations of mechanical forces in cells. Fold formation has mainly been attributed to mechanical force generation at apical cell sides, but several studies indicate a role of mechanical tension at lateral cell sides in this process. However, whether lateral tension increase is sufficient to drive epithelial folding remains unclear. Here, we have used optogenetics to locally increase mechanical force generation at apical, lateral or basal sides of epithelial Drosophila wing disc cells, an important model for studying morphogenesis. We show that optogenetic recruitment of RhoGEF2 to apical, lateral or basal cell sides leads to local accumulation of F-actin and increase in mechanical tension. Increased lateral tension, but not increased apical or basal tension, results in sizeable fold formation. Our results stress the diversification of folding mechanisms between different tissues and highlight the importance of lateral tension increase for epithelial folding.
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Affiliation(s)
- Liyuan Sui
- Institute of Genetics, Technische Universität Dresden, 01062 Dresden, Germany
| | - Christian Dahmann
- Institute of Genetics, Technische Universität Dresden, 01062 Dresden, Germany
- Cluster of Excellence Physics of Life, Technische Universität Dresden, 01062 Dresden, Germany
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33
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The Arf-GEF Steppke promotes F-actin accumulation, cell protrusions and tissue sealing during Drosophila dorsal closure. PLoS One 2020; 15:e0239357. [PMID: 33186390 PMCID: PMC7665897 DOI: 10.1371/journal.pone.0239357] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 11/02/2020] [Indexed: 01/05/2023] Open
Abstract
Cytohesin Arf-GEFs promote actin polymerization and protrusions of cultured cells, whereas the Drosophila cytohesin, Steppke, antagonizes actomyosin networks in several developmental contexts. To reconcile these findings, we analyzed epidermal leading edge actin networks during Drosophila embryo dorsal closure. Here, Steppke is required for F-actin of the actomyosin cable and for actin-based protrusions. steppke mutant defects in the leading edge actin networks are associated with improper sealing of the dorsal midline, but are distinguishable from effects of myosin mis-regulation. Steppke localizes to leading edge cell-cell junctions with accumulations of the F-actin regulator Enabled emanating from either side. Enabled requires Steppke for full leading edge recruitment, and genetic interaction shows the proteins cooperate for dorsal closure. Inversely, Steppke over-expression induces ectopic, actin-rich, lamellar cell protrusions, an effect dependent on the Arf-GEF activity and PH domain of Steppke, but independent of Steppke recruitment to myosin-rich AJs via its coiled-coil domain. Thus, Steppke promotes actin polymerization and cell protrusions, effects that occur in conjunction with Steppke's previously reported regulation of myosin contractility during dorsal closure.
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34
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Kelley CA, Triplett O, Mallick S, Burkewitz K, Mair WB, Cram EJ. FLN-1/filamin is required to anchor the actomyosin cytoskeleton and for global organization of sub-cellular organelles in a contractile tissue. Cytoskeleton (Hoboken) 2020; 77:379-398. [PMID: 32969593 DOI: 10.1002/cm.21633] [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] [Received: 07/28/2020] [Revised: 09/11/2020] [Accepted: 09/17/2020] [Indexed: 01/01/2023]
Abstract
Actomyosin networks are organized in space, direction, size, and connectivity to produce coordinated contractions across cells. We use the C. elegans spermatheca, a tube composed of contractile myoepithelial cells, to study how actomyosin structures are organized. FLN-1/filamin is required for the formation and stabilization of a regular array of parallel, contractile, actomyosin fibers in this tissue. Loss of fln-1 results in the detachment of actin fibers from the basal surface, which then accumulate along the cell junctions and are stabilized by spectrin. In addition, actin and myosin are captured at the nucleus by the linker of nucleoskeleton and cytoskeleton complex (LINC) complex, where they form large foci. Nuclear positioning and morphology, distribution of the endoplasmic reticulum and the mitochondrial network are also disrupted. These results demonstrate that filamin is required to prevent large actin bundle formation and detachment, to prevent excess nuclear localization of actin and myosin, and to ensure correct positioning of organelles.
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Affiliation(s)
- Charlotte A Kelley
- Department of Biology, Northeastern University, Boston, Massachusetts, USA
| | - Olivia Triplett
- Department of Biology, Northeastern University, Boston, Massachusetts, USA
| | - Samyukta Mallick
- Department of Biology, Northeastern University, Boston, Massachusetts, USA
| | - Kristopher Burkewitz
- Department of Genetics and Complex Diseases, Harvard School of Public Health, Boston, Massachusetts, USA.,Department of Cell and Developmental Biology, Vanderbilt School of Medicine, Nashville, Tennessee, USA
| | - William B Mair
- Department of Genetics and Complex Diseases, Harvard School of Public Health, Boston, Massachusetts, USA
| | - Erin J Cram
- Department of Biology, Northeastern University, Boston, Massachusetts, USA
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35
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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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36
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AimB Is a Small Protein Regulator of Cell Size and MreB Assembly. Biophys J 2020; 119:593-604. [PMID: 32416080 DOI: 10.1016/j.bpj.2020.04.029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 04/17/2020] [Accepted: 04/27/2020] [Indexed: 12/27/2022] Open
Abstract
The MreB actin-like cytoskeleton assembles into dynamic polymers that coordinate cell shape in many bacteria. In contrast to most other cytoskeleton systems, few MreB-interacting proteins have been well characterized. Here, we identify a small protein from Caulobacter crescentus, an assembly inhibitor of MreB (AimB). AimB overexpression mimics inhibition of MreB polymerization, leading to increased cell width and MreB delocalization. Furthermore, aimB appears to be essential, and its depletion results in decreased cell width and increased resistance to A22, a small-molecule inhibitor of MreB assembly. Molecular dynamics simulations suggest that AimB binds MreB at its monomer-monomer protofilament interaction cleft and that this interaction is favored for C. crescentus MreB over Escherichia coli MreB because of a closer match in the degree of opening with AimB size, suggesting coevolution of AimB with MreB conformational dynamics in C. crescentus. We support this model through functional analysis of point mutants in both AimB and MreB, photo-cross-linking studies with site-specific unnatural amino acids, and species-specific activity of AimB. Together, our findings are consistent with AimB promoting MreB dynamics by inhibiting monomer-monomer assembly interactions, representing a new mechanism for regulating actin-like polymers and the first identification of a non-toxin MreB assembly inhibitor. Because AimB has only 104 amino acids and small proteins are often poorly characterized, our work suggests the possibility of more bacterial cytoskeletal regulators to be found in this class. Thus, like FtsZ and eukaryotic actin, MreB may have a rich repertoire of regulators to tune its precise assembly and dynamics.
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37
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Zhao C, Zhou Q, Duan H, Wang X, Jia Y, Gong Y, Li W, Dong C, Li Z, Shi W. Laminin 511 Precoating Promotes the Functional Recovery of Transplanted Corneal Endothelial Cells. Tissue Eng Part A 2020; 26:1158-1168. [PMID: 32495687 DOI: 10.1089/ten.tea.2020.0047] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Corneal endothelial dysfunction is a major cause of corneal blindness and is mainly treated by corneal transplantation. However, the global shortage of donor cornea hampers its application. Intracameral injection of cultured primary corneal endothelial cells (CECs) was recently confirmed in clinical trials. However, abnormal adhesion of the grafted CECs affects the application of this strategy. In this study, we explored if laminin 511 (LN511) improves the therapeutic function of the intracameral CEC injection for corneal endothelial dysfunction. To mimic the late stage of corneal endothelial diseases, intense scraping was developed to remove CECs and extracellular matrix of the posterior Descemet's membrane (DM) without DM removal in rabbits. Then, Dulbecco's phosphate-buffered saline (DPBS) and LN511 were intracamerally injected as the control and intervention groups, respectively. We found that the injected LN511 could settle and form a coating on the posterior surface of DM. After CEC transplantation, corneal clarity of rabbits in the LN511 group was rapidly recovered within 7 days, whereas the corneal recovery took 14 days in the DPBS group. Corneal thickness of LN511 group decreased to 413.3 ± 20.8 μm 7 days after operation, which was significantly lower than 1086.3 ± 78.6 μm of DPBS group (p < 0.01). Moreover, for the grafted CECs, LN511 promoted the rapid adhesion, tight junction formation, and expression of Na+/K+-ATPase and ZO-1. In vitro analysis revealed that the functions of LN511 on the cultured human CECs mechanistically depended on the cell density and the nuclear-cytoplasmic translocation of the Yes-associated protein. Our study demonstrated that LN511 precoating promoted the adhesion of the transplanted CECs and enhanced the functional regeneration of the corneal endothelium. Thus, our data suggested that the strategy of LN511 precoating and CECs' intracameral injection could be a potential method for the therapy of corneal endothelial dysfunction. Impact statement Intracameral injection of cultured corneal endothelial cells (CECs) is a potential alternative therapy for corneal endothelial dysfunction and has been proven to be effective in clinical trials. However, abnormal adhesion of the grafted CECs affects its application. In this study, intense scraping was developed to remove CECs and extracellular matrix of the posterior Descemet's membrane (DM) without DM removal for the therapy of late stage of corneal endothelial diseases. Laminin 511 was intracamerally injected to form a coating, improve the posterior DM, enhance the adhesion of the grafted CECs, and promote the functional regeneration of CEC transplantation through Yes-associated protein signaling.
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Affiliation(s)
- Can Zhao
- Department of Medicine, Qingdao University, Qingdao, China.,Qingdao Eye Hospital of Shandong First Medical University, Qingdao, China.,State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University & Shandong Academy of Medical Sciences, Qingdao, China
| | - Qingjun Zhou
- Qingdao Eye Hospital of Shandong First Medical University, Qingdao, China.,State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University & Shandong Academy of Medical Sciences, Qingdao, China
| | - Haoyun Duan
- Qingdao Eye Hospital of Shandong First Medical University, Qingdao, China.,State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University & Shandong Academy of Medical Sciences, Qingdao, China
| | - Xin Wang
- Department of Medicine, Qingdao University, Qingdao, China.,Qingdao Eye Hospital of Shandong First Medical University, Qingdao, China.,State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University & Shandong Academy of Medical Sciences, Qingdao, China
| | - Yanni Jia
- State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University & Shandong Academy of Medical Sciences, Qingdao, China.,Eye Hospital of Shandong First Medical University, Shandong Eye Hospital, Jinan, China
| | - Yajie Gong
- Qingdao Eye Hospital of Shandong First Medical University, Qingdao, China.,State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University & Shandong Academy of Medical Sciences, Qingdao, China
| | - Wenjing Li
- Qingdao Eye Hospital of Shandong First Medical University, Qingdao, China.,State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University & Shandong Academy of Medical Sciences, Qingdao, China
| | - Chunxiao Dong
- Department of Medicine, Qingdao University, Qingdao, China.,Qingdao Eye Hospital of Shandong First Medical University, Qingdao, China.,State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University & Shandong Academy of Medical Sciences, Qingdao, China
| | - Zongyi Li
- Qingdao Eye Hospital of Shandong First Medical University, Qingdao, China.,State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University & Shandong Academy of Medical Sciences, Qingdao, China
| | - Weiyun Shi
- Qingdao Eye Hospital of Shandong First Medical University, Qingdao, China.,State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University & Shandong Academy of Medical Sciences, Qingdao, China.,Eye Hospital of Shandong First Medical University, Shandong Eye Hospital, Jinan, China
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38
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Alexandrova AY, Chikina AS, Svitkina TM. Actin cytoskeleton in mesenchymal-to-amoeboid transition of cancer cells. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2020; 356:197-256. [PMID: 33066874 DOI: 10.1016/bs.ircmb.2020.06.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
During development of metastasis, tumor cells migrate through different tissues and encounter different extracellular matrices. An ability of cells to adapt mechanisms of their migration to these diverse environmental conditions, called migration plasticity, gives tumor cells an advantage over normal cells for long distant dissemination. Different modes of individual cell motility-mesenchymal and amoeboid-are driven by different molecular mechanisms, which largely depend on functions of the actin cytoskeleton that can be modulated in a wide range by cellular signaling mechanisms in response to environmental conditions. Various triggers can switch one motility mode to another, but regulations of these transitions are incompletely understood. However, understanding of the mechanisms driving migration plasticity is instrumental for finding anti-cancer treatment capable to stop cancer metastasis. In this review, we discuss cytoskeletal features, which allow the individually migrating cells to switch between mesenchymal and amoeboid migrating modes, called mesenchymal-to-amoeboid transition (MAT). We briefly describe main characteristics of different cell migration modes, and then discuss the triggering factors that initiate MAT with special attention to cytoskeletal features essential for migration plasticity.
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Affiliation(s)
- Antonina Y Alexandrova
- Laboratory of Mechanisms of Carcinogenesis, N.N. Blokhin Russian Cancer Research Center, Moscow, Russia.
| | - Aleksandra S Chikina
- Cell Migration and Invasion and Spatio-Temporal Regulation of Antigen Presentation teams, UMR144/U932 Institut Curie, Paris, France
| | - Tatyana M Svitkina
- Department of Biology, University of Pennsylvania, Philadelphia, PA, United States
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39
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Coelho NM, Wang A, Petrovic P, Wang Y, Lee W, McCulloch CA. MRIP Regulates the Myosin IIA Activity and DDR1 Function to Enable Collagen Tractional Remodeling. Cells 2020; 9:cells9071672. [PMID: 32664526 PMCID: PMC7407560 DOI: 10.3390/cells9071672] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 07/08/2020] [Accepted: 07/09/2020] [Indexed: 12/18/2022] Open
Abstract
DDR1 is a collagen adhesion-mechanoreceptor expressed in fibrotic lesions. DDR1 mediates non-muscle myosin IIA (NMIIA)-dependent collagen remodeling. We discovered that the myosin phosphatase Rho-interacting protein (MRIP), is enriched in DDR1-NMIIA adhesions on collagen. MRIP regulates RhoA- and myosin phosphatase-dependent myosin activity. We hypothesized that MRIP regulates DDR1-NMIIA interactions to enable cell migration and collagen tractional remodeling. After deletion of MRIP in β1-integrin null cells expressing DDR1, in vitro wound closure, collagen realignment, and contraction were reduced. Cells expressing DDR1 and MRIP formed larger and more abundant DDR1 clusters on collagen than cells cultured on fibronectin or cells expressing DDR1 but null for MRIP or cells expressing a non-activating DDR1 mutant. Deletion of MRIP reduced DDR1 autophosphorylation and blocked myosin light chain-dependent contraction. Deletion of MRIP did not disrupt the association of DDR1 with NMIIA. We conclude that MRIP regulates NMIIA-dependent DDR1 cluster growth and activation. Accordingly, MRIP may provide a novel drug target for dysfunctional DDR1-related collagen tractional remodeling in fibrosis.
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Lechuga S, Ivanov AI. Actin cytoskeleton dynamics during mucosal inflammation: a view from broken epithelial barriers. CURRENT OPINION IN PHYSIOLOGY 2020; 19:10-16. [PMID: 32728653 DOI: 10.1016/j.cophys.2020.06.012] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Disruption of epithelial barriers is a key pathogenic event of mucosal inflammation: It ignites the exaggerated immune response and accelerates tissue damage. Loss of barrier function is attributed to the abnormal structure and permeability of epithelial adherens junctions and tight junctions, driven by inflammatory stimuli through a variety of cellular mechanisms. This review focuses on roles of the actin cytoskeleton in mediating disruption of epithelial junctions and creation of leaky barriers in inflamed tissues. We summarize recent advances in understanding the role of cytoskeletal remodeling driven by actin filament turnover and myosin II-dependent contractility in the homeostatic regulation of epithelial barriers and barrier disruption during mucosal inflammation. We also discuss how the altered biochemical and physical environment of the inflamed tissues could affect the dynamics of the junction-associated actomyosin cytoskeleton, leading to the disruption of epithelial barriers.
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Affiliation(s)
- Susana Lechuga
- Department of Inflammation and Immunity, Lerner Research Institute of Cleveland Clinic Foundation, Cleveland, OH 44195
| | - Andrei I Ivanov
- Department of Inflammation and Immunity, Lerner Research Institute of Cleveland Clinic Foundation, Cleveland, OH 44195
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Alimohamadi H, Smith AS, Nowak RB, Fowler VM, Rangamani P. Non-uniform distribution of myosin-mediated forces governs red blood cell membrane curvature through tension modulation. PLoS Comput Biol 2020; 16:e1007890. [PMID: 32453720 PMCID: PMC7274484 DOI: 10.1371/journal.pcbi.1007890] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 06/05/2020] [Accepted: 04/21/2020] [Indexed: 12/11/2022] Open
Abstract
The biconcave disk shape of the mammalian red blood cell (RBC) is unique to the RBC and is vital for its circulatory function. Due to the absence of a transcellular cytoskeleton, RBC shape is determined by the membrane skeleton, a network of actin filaments cross-linked by spectrin and attached to membrane proteins. While the physical properties of a uniformly distributed actin network interacting with the lipid bilayer membrane have been assumed to control RBC shape, recent experiments reveal that RBC biconcave shape also depends on the contractile activity of nonmuscle myosin IIA (NMIIA) motor proteins. Here, we use the classical Helfrich-Canham model for the RBC membrane to test the role of heterogeneous force distributions along the membrane and mimic the contractile activity of sparsely distributed NMIIA filaments. By incorporating this additional contribution to the Helfrich-Canham energy, we find that the RBC biconcave shape depends on the ratio of forces per unit volume in the dimple and rim regions of the RBC. Experimental measurements of NMIIA densities at the dimple and rim validate our prediction that (a) membrane forces must be non-uniform along the RBC membrane and (b) the force density must be larger in the dimple than the rim to produce the observed membrane curvatures. Furthermore, we predict that RBC membrane tension and the orientation of the applied forces play important roles in regulating this force-shape landscape. Our findings of heterogeneous force distributions on the plasma membrane for RBC shape maintenance may also have implications for shape maintenance in different cell types. The spectrin-actin network of the membrane skeleton plays an important role in controlling specialized cell membrane morphology. In the paradigmatic red blood cell (RBC), where actin filaments are present exclusively in the membrane skeleton, recent experiments reveal that nonmuscle myosin IIA (NMIIA) motor contractility maintains the RBC biconcave disk shape. In this study, we have identified criteria for micron-scale distributions of NMIIA forces at the membrane required to maintain the biconcave disk shape of an RBC in the resting condition. Supported by experimental measurements of RBC NMIIA distribution, we showed that a heterogeneous force distribution with a larger force density at the dimple is able to capture the experimentally observed biconcave morphology of an RBC with better accuracy compared to previous models that did not consider the heterogeneity in the force distribution. Furthermore, we showed that the biconcave geometry of the RBC is closely regulated by the effective membrane tension and the direction of applied forces on the membrane. These findings can be generalized to any force-mediated membrane shape, providing insight into the role of actomyosin forces in prescribing and maintaining the morphology of different cell types.
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Affiliation(s)
- Haleh Alimohamadi
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, California, United States of America
| | - Alyson S. Smith
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States of America
| | - Roberta B. Nowak
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States of America
| | - Velia M. Fowler
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States of America
- Department of Biological Sciences, University of Delaware, Newark, Delaware, United States of America
| | - Padmini Rangamani
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, California, United States of America
- * E-mail:
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Samandar Eweis D, Plastino J. Roles of Actin in the Morphogenesis of the Early Caenorhabditis elegans Embryo. Int J Mol Sci 2020; 21:ijms21103652. [PMID: 32455793 PMCID: PMC7279410 DOI: 10.3390/ijms21103652] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 05/18/2020] [Accepted: 05/19/2020] [Indexed: 12/23/2022] Open
Abstract
The cell shape changes that ensure asymmetric cell divisions are crucial for correct development, as asymmetric divisions allow for the formation of different cell types and therefore different tissues. The first division of the Caenorhabditis elegans embryo has emerged as a powerful model for understanding asymmetric cell division. The dynamics of microtubules, polarity proteins, and the actin cytoskeleton are all key for this process. In this review, we highlight studies from the last five years revealing new insights about the role of actin dynamics in the first asymmetric cell division of the early C. elegans embryo. Recent results concerning the roles of actin and actin binding proteins in symmetry breaking, cortical flows, cortical integrity, and cleavage furrow formation are described.
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Affiliation(s)
- Dureen Samandar Eweis
- Laboratoire Physico-Chimie Curie, Institut Curie, PSL Research University, CNRS, 75005 Paris, France;
- Sorbonne Université, 75005 Paris, France
| | - Julie Plastino
- Laboratoire Physico-Chimie Curie, Institut Curie, PSL Research University, CNRS, 75005 Paris, France;
- Sorbonne Université, 75005 Paris, France
- Correspondence:
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Rodríguez-Fernández JL, Criado-García O. The Chemokine Receptor CCR7 Uses Distinct Signaling Modules With Biased Functionality to Regulate Dendritic Cells. Front Immunol 2020; 11:528. [PMID: 32351499 PMCID: PMC7174648 DOI: 10.3389/fimmu.2020.00528] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 03/09/2020] [Indexed: 12/22/2022] Open
Abstract
Chemotaxis is a molecular mechanism that confers leukocytes the ability to detect gradients of chemoattractants. Chemokine receptors are well-known regulators of chemotaxis in leukocytes; however, they can regulate several other activities in these cells. This information has been often neglected, probably due to the paramount role of chemotaxis in the immune system and in biology. Therefore, the experimental data available on the mechanisms used by chemokine receptors to regulate other functions of leukocytes is sparse. The results obtained in the study of the chemokine receptor CCR7 in dendritic cells (DCs) provide interesting information on this issue. CCR7 guides the DCs from the peripheral tissues to the lymph nodes, where these cells control T cell activation. CCR7 can regulate DC chemotaxis, survival, migratory speed, cytoarchitecture, and endocytosis. Biochemical and functional analyses show: first, that CCR7 uses in DCs the PI3K/Akt pathway to control survival, the MAPK pathway to control chemotaxis, and the RhoA pathways to regulate actin dynamics, which in turn controls migratory speed, cytoarchitecture, and endocytosis; second, that these three signaling pathways behave as modules with a high degree of independence; and third, that although each one of these routes can regulate several functions in different settings, CCR7 promotes in DCs a functional bias in each pathway. The data uncover an interesting mechanism used by CCR7 to regulate the DCs, entailing multifunctional signaling pathways organized in modules with biased functionality. A similar mechanism could be used by other chemoattractant receptors to regulate the functions of leukocytes.
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Affiliation(s)
- José Luis Rodríguez-Fernández
- Centro de Investigaciones Biológicas Margarita Salas, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Olga Criado-García
- Centro de Investigaciones Biológicas Margarita Salas, Consejo Superior de Investigaciones Científicas, Madrid, Spain
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44
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Álvarez-Salamero C, Castillo-González R, Pastor-Fernández G, Mariblanca IR, Pino J, Cibrian D, Navarro MN. IL-23 signaling regulation of pro-inflammatory T-cell migration uncovered by phosphoproteomics. PLoS Biol 2020; 18:e3000646. [PMID: 32203518 PMCID: PMC7117768 DOI: 10.1371/journal.pbio.3000646] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 04/02/2020] [Accepted: 02/28/2020] [Indexed: 01/22/2023] Open
Abstract
Interleukin 23 (IL-23) triggers pathogenic features in pro-inflammatory, IL-17-secreting T cells (Th17 and Tγδ17) that play a key role in the development of inflammatory diseases. However, the IL-23 signaling cascade remains largely undefined. Here, we used quantitative phosphoproteomics to characterize IL-23 signaling in primary murine Th17 cells. We quantified 6,888 phosphorylation sites in Th17 cells and found 168 phosphorylations regulated upon IL-23 stimulation. IL-23 increased the phosphorylation of the myosin regulatory light chain (RLC), an actomyosin contractibility marker, in Th17 and Tγδ17 cells. IL-23-induced RLC phosphorylation required Janus kinase 2 (JAK2) and Rho-associated protein kinase (ROCK) catalytic activity, and further study of the IL-23/ROCK connection revealed an unexpected role of IL-23 in the migration of Tγδ17 and Th17 cells through ROCK activation. In addition, pharmacological inhibition of ROCK reduced Tγδ17 recruitment to inflamed skin upon challenge with inflammatory agent Imiquimod. This work (i) provides new insights into phosphorylation networks that control Th17 cells, (ii) widely expands the current knowledge on IL-23 signaling, and (iii) contributes to the increasing list of immune cells subsets characterized by global phosphoproteomic approaches. Phosphoproteomics of interleukin-17-secreting T cells (Th17 cells) identifies more than 100 phosphorylation events in response to interleukin-23 stimulation, revealing increased phosphorylation of myosin regulatory light chain (RLC) and a role for an IL-23/ROCK pathway in controlling migration of Th17 and Tγδ17 cells.
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Affiliation(s)
- Candelas Álvarez-Salamero
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid (CSIC/UAM), Madrid, Spain
- Departamento de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
- Instituto de Investigación Sanitaria del Hospital Universitario de La Princesa, Universidad Autonoma de Madrid, Madrid, Spain
| | - Raquel Castillo-González
- Instituto de Investigación Sanitaria del Hospital Universitario de La Princesa, Universidad Autonoma de Madrid, Madrid, Spain
| | - Gloria Pastor-Fernández
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid (CSIC/UAM), Madrid, Spain
| | - Isabel R. Mariblanca
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid (CSIC/UAM), Madrid, Spain
| | - Jesús Pino
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid (CSIC/UAM), Madrid, Spain
| | - Danay Cibrian
- Instituto de Investigación Sanitaria del Hospital Universitario de La Princesa, Universidad Autonoma de Madrid, Madrid, Spain
| | - María N. Navarro
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid (CSIC/UAM), Madrid, Spain
- Departamento de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
- Instituto de Investigación Sanitaria del Hospital Universitario de La Princesa, Universidad Autonoma de Madrid, Madrid, Spain
- * E-mail:
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Chen X, Deng Z, He Y, Lu F, Yuan Y. Mechanical Strain Promotes Proliferation of Adipose-Derived Stem Cells Through the Integrin β1-Mediated RhoA/Myosin Light Chain Pathway. Tissue Eng Part A 2020; 26:939-952. [PMID: 32066340 DOI: 10.1089/ten.tea.2019.0266] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
External volume expansion (EVE) promotes proliferation of adipose-derived stem cells (ADSCs) during adipose tissue regeneration. However, the mechanism by which EVE is translated into biochemical signals and subsequently induces proliferation of ADSCs is poorly understood. Here, we investigated the strain in adipose tissue and mechanochemical signaling upon EVE in rats. In addition, the effect of mechanical strain on proliferation of ADSCs was assessed using a custom-built Flexcell device. The level of strain in adipose tissue upon EVE peaked at week 1 and then decreased over time, and the cell proliferation rate was similarly affected. Mechanical strain-dependent activation of integrin β1 and the RhoA/myosin light chain (MLC) pathway was involved in cell proliferation. The proliferation rate of ADSCs was higher under 12% mechanical strain than under 6% and 0% mechanical strain in vitro. Mechanical strain-dependent activation of integrin β1 promoted activation of the small GTPase RhoA and phosphorylation of MLC. Furthermore, knockdown of integrin β1 attenuated activation of the RhoA/MLC pathway and proliferation of ADSCs in response to mechanical strain. Taken together, this study provides the first evidence of mechanochemical signaling in response to EVE. These data may help elucidate the effects of different strain levels on adipose tissue regeneration. Impact statement External volume expansion (EVE) induces adipose tissue regeneration and has great therapeutic potential to correct soft tissue defects. This study showed that EVE promotes proliferation of adipose-derived stem cells by activating integrin β1 and its crucial downstream signaling molecules, namely the small GTPase RhoA and p-myosin light chain. The findings of this study may assist clinical tissue engineering applications and provide new insights into the regulation of adipose tissue regeneration in clinical practice.
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Affiliation(s)
- Xihang Chen
- Department of Plastic and Reconstructive Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, People's Republic of China
| | - Zilong Deng
- Department of Stomatology, Nanfang Hospital, Southern Medical University, Guangzhou, People's Republic of China.,College of Stomatology, Southern Medical University, Guangzhou, People's Republic of China
| | - Yunfan He
- Department of Plastic and Reconstructive Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, People's Republic of China
| | - Feng Lu
- Department of Plastic and Reconstructive Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, People's Republic of China
| | - Yi Yuan
- Department of Plastic and Reconstructive Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, People's Republic of China
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Ko CS, Kalakuntla P, Martin AC. Apical Constriction Reversal upon Mitotic Entry Underlies Different Morphogenetic Outcomes of Cell Division. Mol Biol Cell 2020; 31:1663-1674. [PMID: 32129704 PMCID: PMC7521848 DOI: 10.1091/mbc.e19-12-0673] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
During development, coordinated cell shape changes and cell divisions sculpt tissues. While these individual cell behaviors have been extensively studied, how cell shape changes and cell divisions that occur concurrently in epithelia influence tissue shape is less understood. We addressed this question in two contexts of the early Drosophila embryo: premature cell division during mesoderm invagination, and native ectodermal cell divisions with ectopic activation of apical contractility. Using quantitative live-cell imaging, we demonstrated that mitotic entry reverses apical contractility by interfering with medioapical RhoA signaling. While premature mitotic entry inhibits mesoderm invagination, which relies on apical constriction, mitotic entry in an artificially contractile ectoderm induced ectopic tissue invaginations. Ectopic invaginations resulted from medioapical myosin loss in neighboring mitotic cells. This myosin loss enabled nonmitotic cells to apically constrict through mitotic cell stretching. Thus, the spatial pattern of mitotic entry can differentially regulate tissue shape through signal interference between apical contractility and mitosis.
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Affiliation(s)
- Clint S Ko
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142
| | - Prateek Kalakuntla
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142
| | - Adam C Martin
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142
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Houssin NS, Martin JB, Coppola V, Yoon SO, Plageman TF. Formation and contraction of multicellular actomyosin cables facilitate lens placode invagination. Dev Biol 2020; 462:36-49. [PMID: 32113830 DOI: 10.1016/j.ydbio.2020.02.014] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 02/06/2020] [Accepted: 02/25/2020] [Indexed: 01/23/2023]
Abstract
Embryonic morphogenesis relies on the intrinsic ability of cells, often through remodeling the cytoskeleton, to shape epithelial tissues during development. Epithelial invagination is an example of morphogenesis that depends on this remodeling but the cellular mechanisms driving arrangement of cytoskeletal elements needed for tissue deformation remain incompletely characterized. To elucidate these mechanisms, live fluorescent microscopy and immunohistochemistry on fixed specimens were performed on chick and mouse lens placodes. This analysis revealed the formation of peripherally localized, circumferentially orientated and aligned junctions enriched in F-actin and MyoIIB. Once formed, the aligned junctions contract in a Rho-kinase and non-muscle myosin dependent manner. Further molecular characterization of these junctions revealed a Rho-kinase dependent accumulation of Arhgef11, a RhoA-specific guanine exchange factor known to regulate the formation of actomyosin cables and junctional contraction. In contrast, the localization of the Par-complex protein Par3, was reduced in these circumferentially orientated junctions. In an effort to determine if Par3 plays a negative role in MyoIIB accumulation, Par3-deficient mouse embryos were analyzed which not only revealed an increase in bicellular junctional accumulation of MyoIIB, but also a reduction of Arhgef11. Together, these results highlight the importance of the formation of the multicellular actomyosin cables that appear essential to the initiation of epithelial invagination and implicate the potential role of Arhgef11 and Par3 in their contraction and formation.
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Affiliation(s)
| | - Jessica B Martin
- College of Optometry, The Ohio State University, Columbus, OH, USA
| | - Vincenzo Coppola
- Department of Cancer Biology and Genetics, The Ohio State University, Columbus, OH, USA
| | - Sung Ok Yoon
- Department of Biological Chemistry and Pharmacology, Ohio State University, Columbus, OH, USA
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48
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Zeng C, Zeng B, Dong C, Liu J, Xing F. Rho-ROCK signaling mediates entotic cell death in tumor. Cell Death Discov 2020; 6:4. [PMID: 32123580 PMCID: PMC7026421 DOI: 10.1038/s41420-020-0238-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 10/18/2019] [Accepted: 11/11/2019] [Indexed: 02/06/2023] Open
Affiliation(s)
- Chong Zeng
- Institute of Tissue Transplantation and Immunology, Department of Immunobiology, Jinan University, Guangzhou, China
- MOE Key Laboratory of Tumor Molecular Biology, Key Laboratory of Functional Protein Research of Guangdong, Higher Education Institutes, Jinan University, Guangzhou, China
| | - Boning Zeng
- Institute of Tissue Transplantation and Immunology, Department of Immunobiology, Jinan University, Guangzhou, China
| | - Changjiang Dong
- BioMedical Research Centre, University of East Anglia, NR4 7TJ Norwich, UK
| | - Jing Liu
- School of Stomatology, Jinan University, Guangzhou, China
| | - Feiyue Xing
- Institute of Tissue Transplantation and Immunology, Department of Immunobiology, Jinan University, Guangzhou, China
- MOE Key Laboratory of Tumor Molecular Biology, Key Laboratory of Functional Protein Research of Guangdong, Higher Education Institutes, Jinan University, Guangzhou, China
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49
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Wang A, Kolhe JA, Gioacchini N, Baade I, Brieher WM, Peterson CL, Freeman BC. Mechanism of Long-Range Chromosome Motion Triggered by Gene Activation. Dev Cell 2020; 52:309-320.e5. [PMID: 31902656 DOI: 10.1016/j.devcel.2019.12.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2018] [Revised: 11/18/2019] [Accepted: 12/12/2019] [Indexed: 12/18/2022]
Abstract
Movement of chromosome sites within interphase cells is critical for numerous pathways including RNA transcription and genome organization. Yet, a mechanism for reorganizing chromatin in response to these events had not been reported. Here, we delineate a molecular chaperone-dependent pathway for relocating activated gene loci in yeast. Our presented data support a model in which a two-authentication system mobilizes a gene promoter through a dynamic network of polymeric nuclear actin. Transcription factor-dependent nucleation of a myosin motor propels the gene locus through the actin matrix, and fidelity of the actin association was ensured by ARP-containing chromatin remodelers. Motor activity of nuclear myosin was dependent on the Hsp90 chaperone. Hsp90 further contributed by biasing the remodeler-actin interaction toward nucleosomes with the non-canonical histone H2A.Z, thereby focusing the pathway on select sites such as transcriptionally active genes. Together, the system provides a rapid and effective means to broadly yet selectively mobilize chromatin sites.
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Affiliation(s)
- Anqi Wang
- Department of Cell and Developmental Biology, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
| | - Janhavi A Kolhe
- Department of Cell and Developmental Biology, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
| | - Nate Gioacchini
- Program of Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Imke Baade
- Department of Cell and Developmental Biology, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
| | - William M Brieher
- Department of Cell and Developmental Biology, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
| | - Craig L Peterson
- Program of Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Brian C Freeman
- Department of Cell and Developmental Biology, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA.
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50
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Bryce NS, Failes TW, Stehn JR, Baker K, Zahler S, Arzhaeva Y, Bischof L, Lyons C, Dedova I, Arndt GM, Gaus K, Goult BT, Hardeman EC, Gunning PW, Lock JG. High-Content Imaging of Unbiased Chemical Perturbations Reveals that the Phenotypic Plasticity of the Actin Cytoskeleton Is Constrained. Cell Syst 2019; 9:496-507.e5. [PMID: 31606369 DOI: 10.1016/j.cels.2019.09.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 07/08/2019] [Accepted: 09/06/2019] [Indexed: 12/27/2022]
Abstract
Although F-actin has a large number of binding partners and regulators, the number of phenotypic states available to the actin cytoskeleton is unknown. Here, we quantified 74 features defining filamentous actin (F-actin) and cellular morphology in >25 million cells after treatment with a library of 114,400 structurally diverse compounds. After reducing the dimensionality of these data, only ∼25 recurrent F-actin phenotypes emerged, each defined by distinct quantitative features that could be machine learned. We identified 2,003 unknown compounds as inducers of actin-related phenotypes, including two that directly bind the focal adhesion protein, talin. Moreover, we observed that compounds with distinct molecular mechanisms could induce equivalent phenotypes and that initially divergent cellular responses could converge over time. These findings suggest a conceptual parallel between the actin cytoskeleton and gene regulatory networks, where the theoretical plasticity of interactions is nearly infinite, yet phenotypes in vivo are constrained into a limited subset of practicable configurations.
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Affiliation(s)
- Nicole S Bryce
- School of Medical Sciences, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Tim W Failes
- Australian Cancer Research Foundation Drug Discovery Centre, Children's Cancer Institute, Lowy Cancer Research Centre, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Justine R Stehn
- School of Medical Sciences, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Karen Baker
- School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, UK
| | - Stefan Zahler
- Department of Pharmacy, Ludwig-Maximilians-University, Munich, Germany
| | - Yulia Arzhaeva
- Quantitative Imaging Research Team, CSIRO Data 61, Marsfield, NSW, Australia
| | - Leanne Bischof
- Quantitative Imaging Research Team, CSIRO Data 61, Marsfield, NSW, Australia
| | - Ciaran Lyons
- School of Medical Sciences, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Irina Dedova
- School of Medical Sciences, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Greg M Arndt
- Australian Cancer Research Foundation Drug Discovery Centre, Children's Cancer Institute, Lowy Cancer Research Centre, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Katharina Gaus
- School of Medical Sciences, UNSW Sydney, Sydney, NSW 2052, Australia; EMBL Australia Node in Single Molecule Science, UNSW Sydney, Sydney, NSW 2052, Australia; ARC Centre of Excellence in Advanced Molecular Imaging, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Benjamin T Goult
- School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, UK
| | - Edna C Hardeman
- School of Medical Sciences, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Peter W Gunning
- School of Medical Sciences, UNSW Sydney, Sydney, NSW 2052, Australia
| | - John G Lock
- School of Medical Sciences, UNSW Sydney, Sydney, NSW 2052, Australia.
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