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Korhonen PK, Wang T, Young ND, Byrne JJ, Campos TL, Chang BC, Taki AC, Gasser RB. Analysis of Haemonchus embryos at single cell resolution identifies two eukaryotic elongation factors as intervention target candidates. Comput Struct Biotechnol J 2024; 23:1026-1035. [PMID: 38435301 PMCID: PMC10907403 DOI: 10.1016/j.csbj.2024.01.008] [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: 10/15/2023] [Revised: 01/14/2024] [Accepted: 01/15/2024] [Indexed: 03/05/2024] Open
Abstract
Advances in single cell technologies are allowing investigations of a wide range of biological processes and pathways in animals, such as the multicellular model organism Caenorhabditis elegans - a free-living nematode. However, there has been limited application of such technology to related parasitic nematodes which cause major diseases of humans and animals worldwide. With no vaccines against the vast majority of parasitic nematodes and treatment failures due to drug resistance or inefficacy, new intervention targets are urgently needed, preferably informed by a deep understanding of these nematodes' cellular and molecular biology - which is presently lacking for most worms. Here, we created the first single cell atlas for an early developmental stage of Haemonchus contortus - a highly pathogenic, C. elegans-related parasitic nematode. We obtained and curated RNA sequence (snRNA-seq) data from single nuclei from embryonating eggs of H. contortus (150,000 droplets), and selected high-quality transcriptomic data for > 14,000 single nuclei for analysis, and identified 19 distinct clusters of cells. Guided by comparative analyses with C. elegans, we were able to reproducibly assign seven cell clusters to body wall muscle, hypodermis, neuronal, intestinal or seam cells, and identified eight genes that were transcribed in all cell clusters/types, three of which were inferred to be essential in H. contortus. Two of these genes (i.e. Hc-eef-1A and Hc-eef1G), coding for eukaryotic elongation factors (called Hc-eEF1A and Hc-eEF1G), were also demonstrated to be transcribed and expressed in all key developmental stages of H. contortus. Together with these findings, sequence- and structure-based comparative analyses indicated the potential of Hc-eEF1A and/or Hc-eEF1G as intervention targets within the protein biosynthesis machinery of H. contortus. Future work will focus on single cell studies of all key developmental stages and tissues of H. contortus, and on evaluating the suitability of the two elongation factor proteins as drug targets in H. contortus and related nematodes, with a view to finding new nematocidal drug candidates.
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Affiliation(s)
- Pasi K. Korhonen
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Tao Wang
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Neil D. Young
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Joseph J. Byrne
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Tulio L. Campos
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Bill C.H. Chang
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Aya C. Taki
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Robin B. Gasser
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia
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2
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Linehan JB, Zampetaki A, Werner ME, Heck B, Maddox PS, Fürthauer S, Maddox AS. Subcellular context-specific tuning of actomyosin ring contractility within a common cytoplasm. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.08.607200. [PMID: 39253424 PMCID: PMC11383051 DOI: 10.1101/2024.08.08.607200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 09/11/2024]
Abstract
The non-muscle actomyosin cytoskeleton generates contractile force through the dynamic rearrangement of its constituent parts. Actomyosin rings are a specialization of the non-muscle actomyosin cytoskeleton that drive cell shape changes during division, wound healing, and other events. Contractile rings throughout phylogeny and in a range of cellular contexts are built from conserved components including non-muscle myosin II (NMMII), actin filaments (F-actin), and crosslinking proteins. However, it is unknown whether diverse actomyosin rings close via a single unifying mechanism. To explore how contractile forces are generated by actomyosin rings, we studied three instances of ring closure within the common cytoplasm of the C. elegans oogenic germline: mitotic cytokinesis of germline stem cells (GSCs), apoptosis of meiotic compartments, and cellularization of oocytes. We found that each ring type closed with unique kinetics, protein density and abundance dynamics. These measurements suggested that the mechanism of contractile force generation varied across the subcellular contexts. Next, we formulated a physical model that related the forces generated by filament-filament interactions to the material properties of these rings that dictate the kinetics of their closure. Using this framework, we related the density of conserved cytoskeletal proteins anillin and NMMII to the kinematics of ring closure. We fitted model rings to in situ measurements to estimate parameters that are currently experimentally inaccessible, such as the asymmetric distribution of protein along the length of F-actin, which occurs naturally due to differences in the dimensions of the crosslinker and NMMII filaments. Our work predicted that the role of NMMII varies across these ring types, due in part to its distribution along F-actin and motoring. Our model also predicted that the degree of contractility and the impact of ring material properties on contractility differs among ring types.
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Affiliation(s)
- John B Linehan
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | | | - Michael E Werner
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Bryan Heck
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Paul S Maddox
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | | | - Amy S Maddox
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
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3
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Kohlbrenner T, Berger S, Laranjeira AC, Aegerter-Wilmsen T, Comi LF, deMello A, Hajnal A. Actomyosin-mediated apical constriction promotes physiological germ cell death in C. elegans. PLoS Biol 2024; 22:e3002775. [PMID: 39178318 PMCID: PMC11376560 DOI: 10.1371/journal.pbio.3002775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 09/05/2024] [Accepted: 07/30/2024] [Indexed: 08/25/2024] Open
Abstract
Germ cell apoptosis in Caenorhabditis elegans hermaphrodites is a physiological process eliminating around 60% of all cells in meiotic prophase to maintain tissue homeostasis. In contrast to programmed cell death in the C. elegans soma, the selection of germ cells undergoing apoptosis is stochastic. By live-tracking individual germ cells at the pachytene stage, we found that germ cells smaller than their neighbors are selectively eliminated through apoptosis before differentiating into oocytes. Thus, cell size is a strong predictor of physiological germ cell death. The RAS/MAPK and ECT/RHO/ROCK pathways together regulate germ cell size by controlling actomyosin constriction at the apical rachis bridges, which are cellular openings connecting the syncytial germ cells to a shared cytoplasmic core. Enhancing apical constriction reduces germ cell size and increases the rate of cell death while inhibiting the actomyosin network in the germ cells prevents their death. We propose that actomyosin contractility at the rachis bridges of the syncytial germ cells amplifies intrinsic disparities in cell size. Through this mechanism, the animals can adjust the balance between physiological germ cell death and oocyte differentiation.
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Affiliation(s)
- Tea Kohlbrenner
- Institute of Molecular Life Sciences, University of Zürich, Zürich, Switzerland
- Molecular Life Science PhD Program, University of Zürich and ETH Zürich, Zürich, Switzerland
| | - Simon Berger
- Institute of Molecular Life Sciences, University of Zürich, Zürich, Switzerland
- Institute for Chemical and Bioengineering, ETH Zürich, Zürich, Switzerland
| | - Ana Cristina Laranjeira
- Institute of Molecular Life Sciences, University of Zürich, Zürich, Switzerland
- Molecular Life Science PhD Program, University of Zürich and ETH Zürich, Zürich, Switzerland
| | | | - Laura Filomena Comi
- Institute of Molecular Life Sciences, University of Zürich, Zürich, Switzerland
- Molecular Life Science PhD Program, University of Zürich and ETH Zürich, Zürich, Switzerland
| | - Andrew deMello
- Institute for Chemical and Bioengineering, ETH Zürich, Zürich, Switzerland
| | - Alex Hajnal
- Institute of Molecular Life Sciences, University of Zürich, Zürich, Switzerland
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4
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Werner ME, Ray DD, Breen C, Staddon MF, Jug F, Banerjee S, Maddox AS. Mechanical and biochemical feedback combine to generate complex contractile oscillations in cytokinesis. Curr Biol 2024; 34:3201-3214.e5. [PMID: 38991614 DOI: 10.1016/j.cub.2024.06.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 04/22/2024] [Accepted: 06/13/2024] [Indexed: 07/13/2024]
Abstract
The actomyosin cortex is an active material that generates force to drive shape changes via cytoskeletal remodeling. Cytokinesis is the essential cell division event during which a cortical actomyosin ring closes to separate two daughter cells. Our active gel theory predicted that actomyosin systems controlled by a biochemical oscillator and experiencing mechanical strain would exhibit complex spatiotemporal behavior. To test whether active materials in vivo exhibit spatiotemporally complex kinetics, we imaged the C. elegans embryo with unprecedented temporal resolution and discovered that sections of the cytokinetic cortex undergo periodic phases of acceleration and deceleration. Contractile oscillations exhibited a range of periodicities, including those much longer periods than the timescale of RhoA pulses, which was shorter in cytokinesis than in any other biological context. Modifying mechanical feedback in vivo or in silico revealed that the period of contractile oscillation is prolonged as a function of the intensity of mechanical feedback. Fast local ring ingression occurs where speed oscillations have long periods, likely due to increased local stresses and, therefore, mechanical feedback. Fast ingression also occurs where material turnover is high, in vivo and in silico. We propose that downstream of initiation by pulsed RhoA activity, mechanical feedback, including but not limited to material advection, extends the timescale of contractility beyond that of biochemical input and, therefore, makes it robust to fluctuations in activation. Circumferential propagation of contractility likely allows for sustained contractility despite cytoskeletal remodeling necessary to recover from compaction. Thus, like biochemical feedback, mechanical feedback affords active materials responsiveness and robustness.
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Affiliation(s)
- Michael E Werner
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Dylan D Ray
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Coleman Breen
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Michael F Staddon
- Center for Systems Biology Dresden, Max Planck Institute for the Physics of Complex Systems, and Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Florian Jug
- Computational Biology Research Centre, Human Technopole, Milan, Italy
| | - Shiladitya Banerjee
- Department of Physics, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Amy Shaub Maddox
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
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Connors CQ, Mauro MS, Wiles JT, Countryman AD, Martin SL, Lacroix B, Shirasu-Hiza M, Dumont J, Kasza KE, Davies TR, Canman JC. Germ fate determinants protect germ precursor cell division by reducing septin and anillin levels at the cell division plane. Mol Biol Cell 2024; 35:ar94. [PMID: 38696255 PMCID: PMC11244169 DOI: 10.1091/mbc.e24-02-0096-t] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Revised: 04/22/2024] [Accepted: 04/26/2024] [Indexed: 05/04/2024] Open
Abstract
Animal cell cytokinesis, or the physical division of one cell into two, is thought to be driven by constriction of an actomyosin contractile ring at the division plane. The mechanisms underlying cell type-specific differences in cytokinesis remain unknown. Germ cells are totipotent cells that pass genetic information to the next generation. Previously, using formincyk-1(ts) mutant Caenorhabditis elegans 4-cell embryos, we found that the P2 germ precursor cell is protected from cytokinesis failure and can divide with greatly reduced F-actin levels at the cell division plane. Here, we identified two canonical germ fate determinants required for P2-specific cytokinetic protection: PIE-1 and POS-1. Neither has been implicated previously in cytokinesis. These germ fate determinants protect P2 cytokinesis by reducing the accumulation of septinUNC-59 and anillinANI-1 at the division plane, which here act as negative regulators of cytokinesis. These findings may provide insight into the regulation of cytokinesis in other cell types, especially in stem cells with high potency.
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Affiliation(s)
- Caroline Q. Connors
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY 10032
| | - Michael S. Mauro
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY 10032
| | - J. Tristian Wiles
- Department of Biological Sciences, Columbia University, New York, NY 10027
| | | | - Sophia L. Martin
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY 10032
| | - Benjamin Lacroix
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013 Paris, France
- Université de Montpellier, CNRS, Centre de Recherche en Biologie Cellulaire de Montpellier, UMR 5237 Montpellier, France
| | - Mimi Shirasu-Hiza
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032
| | - Julien Dumont
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013 Paris, France
| | - Karen E. Kasza
- Department of Mechanical Engineering, Columbia University, New York, NY 10027
| | - Timothy R. Davies
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY 10032
- Department of Biosciences, Durham University, Durham DH1 3LE, UK
| | - Julie C. Canman
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY 10032
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Werner ME, Ray DD, Breen C, Staddon MF, Jug F, Banerjee S, Maddox AS. Mechanical positive feedback and biochemical negative feedback combine to generate complex contractile oscillations in cytokinesis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.01.569672. [PMID: 38076901 PMCID: PMC10705528 DOI: 10.1101/2023.12.01.569672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/23/2024]
Abstract
Contractile force generation by the cortical actomyosin cytoskeleton is essential for a multitude of biological processes. The actomyosin cortex behaves as an active material that drives local and large-scale shape changes via cytoskeletal remodeling in response to biochemical cues and feedback loops. Cytokinesis is the essential cell division event during which a cortical actomyosin ring generates contractile force to change cell shape and separate two daughter cells. Our recent work with active gel theory predicts that actomyosin systems under the control of a biochemical oscillator and experiencing mechanical strain will exhibit complex spatiotemporal behavior, but cytokinetic contractility was thought to be kinetically simple. To test whether active materials in vivo exhibit spatiotemporally complex kinetics, we used 4-dimensional imaging with unprecedented temporal resolution and discovered sections of the cytokinetic cortex undergo periodic phases of acceleration and deceleration. Quantification of ingression speed oscillations revealed wide ranges of oscillation period and amplitude. In the cytokinetic ring, activity of the master regulator RhoA pulsed with a timescale of approximately 20 seconds, shorter than that reported for any other biological context. Contractility oscillated with 20-second periodicity and with much longer periods. A combination of in vivo and in silico approaches to modify mechanical feedback revealed that the period of contractile oscillation is prolonged as a function of the intensity of mechanical feedback. Effective local ring ingression is characterized by slower speed oscillations, likely due to increased local stresses and therefore mechanical feedback. Fast ingression also occurs where material turnover is high, in vivo and in silico . We propose that downstream of initiation by pulsed RhoA activity, mechanical positive feedback, including but not limited to material advection, extends the timescale of contractility beyond that of biochemical input and therefore makes it robust to fluctuations in activation. Circumferential propagation of contractility likely allows sustained contractility despite cytoskeletal remodeling necessary to recover from compaction. Our work demonstrates that while biochemical feedback loops afford systems responsiveness and robustness, mechanical feedback must also be considered to describe and understand the behaviors of active materials in vivo .
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7
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Connors CQ, Mauro MS, Tristian Wiles J, Countryman AD, Martin SL, Lacroix B, Shirasu-Hiza M, Dumont J, Kasza KE, Davies TR, Canman JC. Germ fate determinants protect germ precursor cell division by restricting septin and anillin levels at the division plane. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.17.566773. [PMID: 38014027 PMCID: PMC10680835 DOI: 10.1101/2023.11.17.566773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Animal cell cytokinesis, or the physical division of one cell into two, is thought to be driven by constriction of an actomyosin contractile ring at the division plane. The mechanisms underlying cell type-specific differences in cytokinesis remain unknown. Germ cells are totipotent cells that pass genetic information to the next generation. Previously, using formin cyk-1 (ts) mutant C. elegans embryos, we found that the P2 germ precursor cell is protected from cytokinesis failure and can divide without detectable F-actin at the division plane. Here, we identified two canonical germ fate determinants required for P2-specific cytokinetic protection: PIE-1 and POS-1. Neither has been implicated previously in cytokinesis. These germ fate determinants protect P2 cytokinesis by reducing the accumulation of septin UNC-59 and anillin ANI-1 at the division plane, which here act as negative regulators of cytokinesis. These findings may provide insight into cytokinetic regulation in other cell types, especially in stem cells with high potency.
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8
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Cortes DB, Maddox PS, Nédéléç FJ, Maddox AS. Contractile ring composition dictates kinetics of in silico contractility. Biophys J 2023; 122:3611-3629. [PMID: 36540027 PMCID: PMC10541479 DOI: 10.1016/j.bpj.2022.12.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 11/12/2022] [Accepted: 12/16/2022] [Indexed: 12/24/2022] Open
Abstract
Constriction kinetics of the cytokinetic ring are expected to depend on dynamic adjustment of contractile ring composition, but the impact of ring component abundance dynamics on ring constriction is understudied. Computational models generally assume that contractile networks maintain constant total amounts of components, which is not always true. To test how compositional dynamics affect constriction kinetics, we first measured F-actin, non-muscle myosin II, septin, and anillin during Caenorhabditis elegans zygotic mitosis. A custom microfluidic device that positioned the cell with the division plane parallel to a light sheet allowed even illumination of the cytokinetic ring. Measured component abundances were implemented in a three-dimensional agent-based model of a membrane-associated contractile ring. With constant network component amounts, constriction completed with biologically unrealistic kinetics. However, imposing the measured changes in component quantities allowed this model to elicit realistic constriction kinetics. Simulated networks were more sensitive to changes in motor and filament amounts than those of crosslinkers and tethers. Our findings highlight the importance of network composition for actomyosin contraction kinetics.
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Affiliation(s)
- Daniel B Cortes
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC.
| | - Paul S Maddox
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Francois J Nédéléç
- Sainsbury Laboratory, University of Cambridge, Cambridge, United Kingdom
| | - Amy Shaub Maddox
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC.
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9
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Perry JA, Werner ME, Rivenbark L, Maddox AS. Caenorhabditis elegans septins contribute to the development and structure of the oogenic germline. Cytoskeleton (Hoboken) 2023; 80:215-227. [PMID: 37265173 PMCID: PMC10524836 DOI: 10.1002/cm.21763] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 04/27/2023] [Accepted: 05/04/2023] [Indexed: 06/03/2023]
Abstract
Oocytes must be exceptionally large cells in order to support embryonic development. Throughout animal phylogeny, a specialized cell called a syncytium, wherein many nuclei share a continuous cytoplasm, achieves oogenesis. The syncytial nature of germline architecture is key to its function and depends on conserved components of the cortical cytoskeleton. Septins form non-polar cytoskeletal polymers that associate with membranes. In the syncytial germline of the nematode Caenorhabditis elegans, septins are highly enriched on the cortex and generally required for fertility, but the role of septins in the germline is poorly understood. We report that the C. elegans septins, UNC-59 and UNC-61, are important for germline extension during development, the maintenance of its syncytial architecture, and production of oocytes. While much of our findings substantiate the idea that the two C. elegans septins act together, we also found evidence that they have distinct functions. Loss of UNC-61 perturbed germline extension during germline development, while the loss of UNC-59 function severely affected germline architecture in adult hermaphrodites. Consultation of clustering results from a large-scale high-throughput screen suggested that septins are involved in germ cell proliferation and/or differentiation. In sum, our findings implicate a conserved cytoskeletal component in the complex architecture of a germline syncytium.
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Affiliation(s)
- Jenna A Perry
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Michael E Werner
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Larry Rivenbark
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Amy Shaub Maddox
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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10
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Polyakova N, Kalashnikova M, Belyavsky A. Non-Classical Intercellular Communications: Basic Mechanisms and Roles in Biology and Medicine. Int J Mol Sci 2023; 24:ijms24076455. [PMID: 37047428 PMCID: PMC10095225 DOI: 10.3390/ijms24076455] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 03/27/2023] [Accepted: 03/28/2023] [Indexed: 04/03/2023] Open
Abstract
In multicellular organisms, interactions between cells and intercellular communications form the very basis of the organism’s survival, the functioning of its systems, the maintenance of homeostasis and adequate response to the environment. The accumulated experimental data point to the particular importance of intercellular communications in determining the fate of cells, as well as their differentiation and plasticity. For a long time, it was believed that the properties and behavior of cells were primarily governed by the interactions of secreted or membrane-bound ligands with corresponding receptors, as well as direct intercellular adhesion contacts. In this review, we describe various types of other, non-classical intercellular interactions and communications that have recently come into the limelight—in particular, the broad repertoire of extracellular vesicles and membrane protrusions. These communications are mediated by large macromolecular structural and functional ensembles, and we explore here the mechanisms underlying their formation and present current data that reveal their roles in multiple biological processes. The effects mediated by these new types of intercellular communications in normal and pathological states, as well as therapeutic applications, are also discussed. The in-depth study of novel intercellular interaction mechanisms is required for the establishment of effective approaches for the control and modification of cell properties both for basic research and the development of radically new therapeutic strategies.
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Affiliation(s)
- Natalia Polyakova
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Vavilova 32, 119991 Moscow, Russia
| | - Maria Kalashnikova
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Vavilova 32, 119991 Moscow, Russia
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Butlerova 5A, 117485 Moscow, Russia
| | - Alexander Belyavsky
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Vavilova 32, 119991 Moscow, Russia
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Butlerova 5A, 117485 Moscow, Russia
- Correspondence:
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11
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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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12
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Ozugergin I, Piekny A. Diversity is the spice of life: An overview of how cytokinesis regulation varies with cell type. Front Cell Dev Biol 2022; 10:1007614. [PMID: 36420142 PMCID: PMC9676254 DOI: 10.3389/fcell.2022.1007614] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Accepted: 10/24/2022] [Indexed: 09/01/2023] Open
Abstract
Cytokinesis is required to physically cleave a cell into two daughters at the end of mitosis. Decades of research have led to a comprehensive understanding of the core cytokinesis machinery and how it is regulated in animal cells, however this knowledge was generated using single cells cultured in vitro, or in early embryos before tissues develop. This raises the question of how cytokinesis is regulated in diverse animal cell types and developmental contexts. Recent studies of distinct cell types in the same organism or in similar cell types from different organisms have revealed striking differences in how cytokinesis is regulated, which includes different threshold requirements for the structural components and the mechanisms that regulate them. In this review, we highlight these differences with an emphasis on pathways that are independent of the mitotic spindle, and operate through signals associated with the cortex, kinetochores, or chromatin.
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Affiliation(s)
- Imge Ozugergin
- Department of Biology, McGill University, Montreal, QC, Canada
- Department of Biology, Concordia University, Montreal, QC, Canada
| | - Alisa Piekny
- Department of Biology, Concordia University, Montreal, QC, Canada
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13
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Gerhold AR, Labbé JC, Singh R. Uncoupling cell division and cytokinesis during germline development in metazoans. Front Cell Dev Biol 2022; 10:1001689. [PMID: 36407108 PMCID: PMC9669650 DOI: 10.3389/fcell.2022.1001689] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Accepted: 10/17/2022] [Indexed: 11/06/2022] Open
Abstract
The canonical eukaryotic cell cycle ends with cytokinesis, which physically divides the mother cell in two and allows the cycle to resume in the newly individualized daughter cells. However, during germline development in nearly all metazoans, dividing germ cells undergo incomplete cytokinesis and germ cells stay connected by intercellular bridges which allow the exchange of cytoplasm and organelles between cells. The near ubiquity of incomplete cytokinesis in animal germ lines suggests that this is an ancient feature that is fundamental for the development and function of this tissue. While cytokinesis has been studied for several decades, the mechanisms that enable regulated incomplete cytokinesis in germ cells are only beginning to emerge. Here we review the current knowledge on the regulation of germ cell intercellular bridge formation, focusing on findings made using mouse, Drosophila melanogaster and Caenorhabditis elegans as experimental systems.
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Affiliation(s)
- Abigail R. Gerhold
- Department of Biology, McGill University, Montréal, QC, Canada
- *Correspondence: Abigail R. Gerhold, ; Jean-Claude Labbé,
| | - Jean-Claude Labbé
- Institute for Research in Immunology and Cancer (IRIC), Montréal, QC, Canada
- Department of Pathology and Cell Biology, Université de Montréal, Succ. Centre-ville, Montréal, QC, Canada
- *Correspondence: Abigail R. Gerhold, ; Jean-Claude Labbé,
| | - Ramya Singh
- Department of Biology, McGill University, Montréal, QC, Canada
- Institute for Research in Immunology and Cancer (IRIC), Montréal, QC, Canada
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14
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Daly CA, Hall ET, Ogden SK. Regulatory mechanisms of cytoneme-based morphogen transport. Cell Mol Life Sci 2022; 79:119. [PMID: 35119540 PMCID: PMC8816744 DOI: 10.1007/s00018-022-04148-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 01/05/2022] [Accepted: 01/12/2022] [Indexed: 01/07/2023]
Abstract
During development and tissue homeostasis, cells must communicate with their neighbors to ensure coordinated responses to instructional cues. Cues such as morphogens and growth factors signal at both short and long ranges in temporal- and tissue-specific manners to guide cell fate determination, provide positional information, and to activate growth and survival responses. The precise mechanisms by which such signals traverse the extracellular environment to ensure reliable delivery to their intended cellular targets are not yet clear. One model for how this occurs suggests that specialized filopodia called cytonemes extend between signal-producing and -receiving cells to function as membrane-bound highways along which information flows. A growing body of evidence supports a crucial role for cytonemes in cell-to-cell communication. Despite this, the molecular mechanisms by which cytonemes are initiated, how they grow, and how they deliver specific signals are only starting to be revealed. Herein, we discuss recent advances toward improved understanding of cytoneme biology. We discuss similarities and differences between cytonemes and other types of cellular extensions, summarize what is known about how they originate, and discuss molecular mechanisms by which their activity may be controlled in development and tissue homeostasis. We conclude by highlighting important open questions regarding cytoneme biology, and comment on how a clear understanding of their function may provide opportunities for treating or preventing disease.
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Affiliation(s)
- Christina A Daly
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, 262 Danny Thomas Pl. MS340, Memphis, TN, 38105, USA
- St. Jude Graduate School of Biomedical Sciences, St. Jude Children's Research Hospital, 262 Danny Thomas Pl, MS 1500, Memphis, TN, 38105, USA
| | - Eric T Hall
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, 262 Danny Thomas Pl. MS340, Memphis, TN, 38105, USA
| | - Stacey K Ogden
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, 262 Danny Thomas Pl. MS340, Memphis, TN, 38105, USA.
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15
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From primordial germ cells to spermatids in Caenorhabditis elegans. Semin Cell Dev Biol 2021; 127:110-120. [PMID: 34930663 DOI: 10.1016/j.semcdb.2021.12.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 11/17/2021] [Accepted: 12/07/2021] [Indexed: 12/24/2022]
Abstract
Development of a syncytial germline for gamete formation requires complex regulation of cytokinesis and cytoplasmic remodeling. Recently, several uncovered cellular events have been investigated in the Caenorhabditis elegans (C. elegans) germline. In these cellular processes, the factors involved in contractility are highly conserved with those of mitosis and meiosis. However, the underlying regulatory mechanisms are far more complicated than previously thought, likely due to the single syncytial germline structure. In this review, we highlight how the proteins involved in contractility ensure faithful cell division in different cellular contexts and how they contribute to maintaining intercellular bridge stability. In addition, we discuss the current understanding of the cellular events of cytokinesis and cytoplasmic remodeling during the development of the C. elegans germline, including progenitor germ cells, germ cells, and spermatocytes. Comparisons are made with relevant systems in Drosophila melanogaster (D. melanogaster) and other animal models.
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16
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Bauer J, Poupart V, Goupil E, Nguyen KCQ, Hall DH, Labbé JC. The initial expansion of the C. elegans syncytial germ line is coupled to incomplete primordial germ cell cytokinesis. Development 2021; 148:dev199633. [PMID: 34195824 PMCID: PMC8327289 DOI: 10.1242/dev.199633] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 06/25/2021] [Indexed: 01/06/2023]
Abstract
The C. elegans germline is organized as a syncytium in which each germ cell possesses an intercellular bridge that is maintained by a stable actomyosin ring and connected to a common pool of cytoplasm, termed the rachis. How germ cells undergo cytokinesis while maintaining this syncytial architecture is not completely understood. Here, we use live imaging to characterize primordial germ cell (PGC) division in C. elegans first-stage larvae. We show that each PGC possesses a stable intercellular bridge that connects it to a common pool of cytoplasm, which we term the proto-rachis. We further show that the first PGC cytokinesis is incomplete and that the stabilized cytokinetic ring progressively moves towards the proto-rachis and eventually integrates with it. Our results support a model in which the initial expansion of the C. elegans syncytial germline occurs by incomplete cytokinesis, where one daughter germ cell inherits the actomyosin ring that was newly formed by stabilization of the cytokinetic ring, while the other inherits the pre-existing stable actomyosin ring. We propose that such a mechanism of iterative cytokinesis incompletion underpins C. elegans germline expansion and maintenance.
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Affiliation(s)
- Jack Bauer
- Institute for Research in Immunology and Cancer (IRIC), Université de Montréal, C.P. 6128, Succ. Centre-ville, Montréal, QC H3C 3J7, Canada
| | - Vincent Poupart
- Institute for Research in Immunology and Cancer (IRIC), Université de Montréal, C.P. 6128, Succ. Centre-ville, Montréal, QC H3C 3J7, Canada
| | - Eugénie Goupil
- Institute for Research in Immunology and Cancer (IRIC), Université de Montréal, C.P. 6128, Succ. Centre-ville, Montréal, QC H3C 3J7, Canada
| | - Ken C. Q. Nguyen
- Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - David H. Hall
- Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Jean-Claude Labbé
- Institute for Research in Immunology and Cancer (IRIC), Université de Montréal, C.P. 6128, Succ. Centre-ville, Montréal, QC H3C 3J7, Canada
- Department of Pathology and Cell Biology, Université de Montréal, C.P. 6128, Succ. Centre-ville, Montréal, QC H3C 3J7, Canada
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17
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Chartier NT, Mukherjee A, Pfanzelter J, Fürthauer S, Larson BT, Fritsch AW, Amini R, Kreysing M, Jülicher F, Grill SW. A hydraulic instability drives the cell death decision in the nematode germline. NATURE PHYSICS 2021; 17:920-925. [PMID: 34777551 PMCID: PMC8548275 DOI: 10.1038/s41567-021-01235-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 03/30/2021] [Indexed: 05/02/2023]
Abstract
Oocytes are large cells that develop into an embryo upon fertilization1. As interconnected germ cells mature into oocytes, some of them grow-typically at the expense of others that undergo cell death2-4. We present evidence that in the nematode Caenorhabditis elegans, this cell-fate decision is mechanical and related to tissue hydraulics. An analysis of germ cell volumes and material fluxes identifies a hydraulic instability that amplifies volume differences and causes some germ cells to grow and others to shrink, a phenomenon that is related to the two-balloon instability5. Shrinking germ cells are extruded and they die, as we demonstrate by artificially reducing germ cell volumes via thermoviscous pumping6. Our work reveals a hydraulic symmetry-breaking transition central to the decision between life and death in the nematode germline.
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Affiliation(s)
| | - Arghyadip Mukherjee
- Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), Dresden, Germany
- Max Planck Institute for the Physics of Complex Systems (MPI-PKS), Dresden, Germany
- Center for Systems Biology Dresden, Dresden, Germany
| | - Julia Pfanzelter
- Biotechnology Center, TU Dresden, Dresden, Germany
- Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), Dresden, Germany
| | | | - Ben T. Larson
- Department of Molecular and Cell Biology, University of California, Berkeley, CA USA
- Biophysics Graduate Group, University of California, Berkeley, CA USA
| | - Anatol W. Fritsch
- Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), Dresden, Germany
| | - Rana Amini
- Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), Dresden, Germany
| | - Moritz Kreysing
- Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), Dresden, Germany
- Center for Systems Biology Dresden, Dresden, Germany
- Cluster of Excellence—Physics of Life, TU Dresden, Dresden, Germany
| | - Frank Jülicher
- Max Planck Institute for the Physics of Complex Systems (MPI-PKS), Dresden, Germany
- Center for Systems Biology Dresden, Dresden, Germany
- Cluster of Excellence—Physics of Life, TU Dresden, Dresden, Germany
| | - Stephan W. Grill
- Biotechnology Center, TU Dresden, Dresden, Germany
- Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), Dresden, Germany
- Center for Systems Biology Dresden, Dresden, Germany
- Cluster of Excellence—Physics of Life, TU Dresden, Dresden, Germany
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18
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Sartages M, Floridia E, García-Colomer M, Iglesias C, Macía M, Peñas P, Couraud PO, Romero IA, Weksler B, Pombo CM, Zalvide J. High Levels of Receptor Tyrosine Kinases in CCM3-Deficient Cells Increase Their Susceptibility to Tyrosine Kinase Inhibition. Biomedicines 2020; 8:E624. [PMID: 33348877 PMCID: PMC7766026 DOI: 10.3390/biomedicines8120624] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 12/14/2020] [Accepted: 12/15/2020] [Indexed: 11/25/2022] Open
Abstract
Cerebral cavernous malformations (CCMs) are vascular malformations that can be the result of the deficiency of one of the CCM genes. Their only present treatment is surgical removal, which is not always possible, and an alternative pharmacological strategy to eliminate them is actively sought. We have studied the effect of the lack of one of the CCM genes, CCM3, in endothelial and non-endothelial cells. By comparing protein expression in control and CCM3-silenced cells, we found that the levels of the Epidermal Growth Factor Receptor (EGFR) are higher in CCM3-deficient cells, which adds to the known upregulation of Vascular Endothelial Growth Factor Receptor 2 (VEGFR2) in these cells. Whereas VEGFR2 is upregulated at the mRNA level, EGFR has a prolonged half-life. Inhibition of EGFR family members in CCM3-deficient cells does not revert the known cellular effects of lack of CCM genes, but it induces significantly more apoptosis in CCM3-deficient cells than in control cells. We propose that the susceptibility to tyrosine kinase inhibitors of CCM3-deficient cells can be harnessed to kill the abnormal cells of these lesions and thus treat CCMs pharmacologically.
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Affiliation(s)
- Miriam Sartages
- Department of Physiology, Centro Singular de Medicina Molecular e Enfermedades Crónicas (CiMUS), Instituto Sanitario de Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, 15703 Santiago de Compostela, Spain; (M.S.); (E.F.); (M.G.-C.); (C.I.); (C.M.P.)
| | - Ebel Floridia
- Department of Physiology, Centro Singular de Medicina Molecular e Enfermedades Crónicas (CiMUS), Instituto Sanitario de Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, 15703 Santiago de Compostela, Spain; (M.S.); (E.F.); (M.G.-C.); (C.I.); (C.M.P.)
- IQVIA RDS Ireland Limited, Eastpoint Business Park, Estuary House, Fairview, Dublin 3, D03 K7W7 Leinster, Ireland
| | - Mar García-Colomer
- Department of Physiology, Centro Singular de Medicina Molecular e Enfermedades Crónicas (CiMUS), Instituto Sanitario de Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, 15703 Santiago de Compostela, Spain; (M.S.); (E.F.); (M.G.-C.); (C.I.); (C.M.P.)
| | - Cristina Iglesias
- Department of Physiology, Centro Singular de Medicina Molecular e Enfermedades Crónicas (CiMUS), Instituto Sanitario de Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, 15703 Santiago de Compostela, Spain; (M.S.); (E.F.); (M.G.-C.); (C.I.); (C.M.P.)
| | - Manuel Macía
- Servicio de Obstetricia y Ginecología Hospital Clínico Universitario Santiago, 15703 Santiago de Compostela, Spain; (M.M.); (P.P.)
| | - Patricia Peñas
- Servicio de Obstetricia y Ginecología Hospital Clínico Universitario Santiago, 15703 Santiago de Compostela, Spain; (M.M.); (P.P.)
| | | | - Ignacio A. Romero
- Department of Life, Health and Chemical Sciences, The Open University, Milton Keynes MK7 6AA, UK;
| | - Babette Weksler
- Weill Medical College, Cornell University, 1300 York Ave, New York, NY 10065, USA;
| | - Celia M. Pombo
- Department of Physiology, Centro Singular de Medicina Molecular e Enfermedades Crónicas (CiMUS), Instituto Sanitario de Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, 15703 Santiago de Compostela, Spain; (M.S.); (E.F.); (M.G.-C.); (C.I.); (C.M.P.)
| | - Juan Zalvide
- Department of Physiology, Centro Singular de Medicina Molecular e Enfermedades Crónicas (CiMUS), Instituto Sanitario de Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, 15703 Santiago de Compostela, Spain; (M.S.); (E.F.); (M.G.-C.); (C.I.); (C.M.P.)
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19
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Gordon K. Recent Advances in the Genetic, Anatomical, and Environmental Regulation of the C. elegans Germ Line Progenitor Zone. J Dev Biol 2020; 8:E14. [PMID: 32707774 PMCID: PMC7559772 DOI: 10.3390/jdb8030014] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Revised: 07/13/2020] [Accepted: 07/15/2020] [Indexed: 12/16/2022] Open
Abstract
The C. elegans germ line and its gonadal support cells are well studied from a developmental genetics standpoint and have revealed many foundational principles of stem cell niche biology. Among these are the observations that a niche-like cell supports a self-renewing stem cell population with multipotential, differentiating daughter cells. While genetic features that distinguish stem-like cells from their differentiating progeny have been defined, the mechanisms that structure these populations in the germ line have yet to be explained. The spatial restriction of Notch activation has emerged as an important genetic principle acting in the distal germ line. Synthesizing recent findings, I present a model in which the germ stem cell population of the C. elegans adult hermaphrodite can be recognized as two distinct anatomical and genetic populations. This review describes the recent progress that has been made in characterizing the undifferentiated germ cells and gonad anatomy, and presents open questions in the field and new directions for research to pursue.
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Affiliation(s)
- Kacy Gordon
- Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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20
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Bell KR, Werner ME, Doshi A, Cortes DB, Sattler A, Vuong-Brender T, Labouesse M, Maddox AS. Novel cytokinetic ring components drive negative feedback in cortical contractility. Mol Biol Cell 2020; 31:1623-1636. [PMID: 32491957 PMCID: PMC7521795 DOI: 10.1091/mbc.e20-05-0304] [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: 11/26/2022] Open
Abstract
Actomyosin cortical contractility drives many cell shape changes including cytokinetic furrowing. While positive regulation of contractility is well characterized, counterbalancing negative regulation and mechanical brakes are less well understood. The small GTPase RhoA is a central regulator, activating cortical actomyosin contractility during cytokinesis and other events. Here we report how two novel cytokinetic ring components, GCK-1 (germinal center kinase-1) and CCM-3 (cerebral cavernous malformations-3), participate in a negative feedback loop among RhoA and its cytoskeletal effectors to inhibit contractility. GCK-1 and CCM-3 are recruited by active RhoA and anillin to the cytokinetic ring, where they in turn limit RhoA activity and contractility. This is evidenced by increased RhoA activity, anillin and nonmuscle myosin II in the cytokinetic ring, and faster cytokinetic furrowing, following depletion of GCK-1 or CCM-3. GCK-1 or CCM-3 depletion also reduced RGA-3 levels in pulses and increased baseline RhoA activity and pulsed contractility during zygote polarization. Together, our results suggest that GCK-1 and CCM-3 regulate cortical actomyosin contractility via negative feedback. These findings have implications for the molecular and cellular mechanisms of cerebral cavernous malformation pathologies.
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Affiliation(s)
- Kathryn Rehain Bell
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599.,Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Michael E Werner
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Anusha Doshi
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Daniel B Cortes
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Adam Sattler
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Thanh Vuong-Brender
- Institut de Biologie Paris-Seine, Sorbonne Université, INSERM, 75005 Paris, France
| | - Michel Labouesse
- Institut de Biologie Paris-Seine, Sorbonne Université, INSERM, 75005 Paris, France
| | - Amy Shaub Maddox
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599.,Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
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21
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Peterman E, Valius M, Prekeris R. CLIC4 is a cytokinetic cleavage furrow protein that regulates cortical cytoskeleton stability during cell division. J Cell Sci 2020; 133:jcs241117. [PMID: 32184265 PMCID: PMC7240295 DOI: 10.1242/jcs.241117] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 03/02/2020] [Indexed: 12/31/2022] Open
Abstract
During mitotic cell division, the actomyosin cytoskeleton undergoes several dynamic changes that play key roles in progression through mitosis. Although the regulators of cytokinetic ring formation and contraction are well established, proteins that regulate cortical stability during anaphase and telophase have been understudied. Here, we describe a role for CLIC4 in regulating actin and actin regulators at the cortex and cytokinetic cleavage furrow during cytokinesis. We first describe CLIC4 as a new component of the cytokinetic cleavage furrow that is required for successful completion of mitotic cell division. We also demonstrate that CLIC4 regulates the remodeling of the sub-plasma-membrane actomyosin network within the furrow by recruiting MST4 kinase (also known as STK26) and regulating ezrin phosphorylation. This work identifies and characterizes new molecular players involved in regulating cortex stiffness and blebbing during the late stages of cytokinetic furrowing.
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Affiliation(s)
- Eric Peterman
- Department of Cell and Developmental Biology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Mindaugas Valius
- Proteomics Center, Institute of Biochemistry, Vilnius University Life Sciences Center, Vilnius 10257, Lithuania
| | - Rytis Prekeris
- Department of Cell and Developmental Biology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
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22
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Abstract
The Ran pathway has a well-described function in nucleocytoplasmic transport, where active Ran dissociates importin/karyopherin-bound cargo containing a nuclear localization signal (NLS) in the nucleus. As cells enter mitosis, the nuclear envelope breaks down and a gradient of active Ran forms where levels are highest near chromatin. This gradient plays a crucial role in regulating mitotic spindle assembly, where active Ran binds to and releases importins from NLS-containing spindle assembly factors. An emerging theme is that the Ran gradient also regulates the actomyosin cortex for processes including polar body extrusion during meiosis, and cytokinesis. For these events, active Ran could play an inhibitory role, where importin-binding may help promote or stabilize a conformation or interaction that favours the recruitment and function of cortical regulators. For either spindle assembly or cortical polarity, the gradient of active Ran determines the extent of importin-binding, the effects of which could vary for different proteins.
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Affiliation(s)
- Imge Ozugergin
- Department of Biology, Concordia University, Montreal, QC, Canada
| | - Alisa Piekny
- Department of Biology, Concordia University, Montreal, QC, Canada
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23
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Lan H, Wang X, Jiang L, Wu J, Wan X, Zeng L, Zhang D, Lin Y, Hou C, Wu S, Tse YC. An extracellular matrix protein promotes anillin-dependent processes in the Caenorhabditis elegans germline. Life Sci Alliance 2019; 2:2/2/e201800152. [PMID: 30988161 PMCID: PMC6467243 DOI: 10.26508/lsa.201800152] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 04/04/2019] [Accepted: 04/04/2019] [Indexed: 01/25/2023] Open
Abstract
The extracellular matrix protein Hemicentin (HIM-4) is an extracellular factor that regulates anillin (ANI-1) for germ cell membrane stabilization and contractile ring formation in C.elegans germline cells. Cell division requires constriction of an actomyosin ring to segregate the genetic material equally into two daughter cells. The spatial and temporal regulation of the contractile ring at the division plane primarily depends on intracellular signals mediated by the centralspindlin complex and astral microtubules. Although much investigative work has elucidated intracellular factors and mechanisms controlling this process, the extracellular regulation of cytokinesis remains unclear. Thus far, the extracellular matrix protein Hemicentin (HIM-4) has been proposed to be required for cleavage furrow stabilization. The underlying molecular mechanism, however, has remained largely unknown. Here, we show that HIM-4 and anillin (ANI-1) genetically act in the same pathway to maintain the rachis bridge stability in the germline. Our FRAP experiments further reveal that HIM-4 restricts the motility of ANI-1. In addition, we demonstrate that HIM-4 is recruited to the cleavage site in dividing germ cells and promotes the proper ingression of the cleavage membrane. Collectively, we propose that HIM-4 is an extracellular factor that regulates ANI-1 for germ cell membrane stabilization and contractile ring formation in Caenorhabditis elegans germline cells.
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Affiliation(s)
- Hongxia Lan
- Department of Biology, Southern University of Science and Technology (SUSTech), Shenzhen, China.,State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin, P.R. China
| | - Xinyan Wang
- Department of Biology, Southern University of Science and Technology (SUSTech), Shenzhen, China.,Guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research, Shenzhen Key Laboratory of Cell Microenvironment, SUSTech, Shenzhen, China.,Centre of Reproduction, Development and Aging, Faculty of Health Sciences, University of Macau, Macau, China
| | - Ling Jiang
- Department of Biology, Southern University of Science and Technology (SUSTech), Shenzhen, China.,Guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research, Shenzhen Key Laboratory of Cell Microenvironment, SUSTech, Shenzhen, China
| | - Jianjian Wu
- Department of Biology, Southern University of Science and Technology (SUSTech), Shenzhen, China
| | - Xuan Wan
- Department of Biology, Southern University of Science and Technology (SUSTech), Shenzhen, China.,Guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research, Shenzhen Key Laboratory of Cell Microenvironment, SUSTech, Shenzhen, China
| | - Lidan Zeng
- Department of Biology, Southern University of Science and Technology (SUSTech), Shenzhen, China
| | - Dandan Zhang
- Department of Biology, Southern University of Science and Technology (SUSTech), Shenzhen, China.,Guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research, Shenzhen Key Laboratory of Cell Microenvironment, SUSTech, Shenzhen, China
| | - Yiyan Lin
- Department of Biology, Southern University of Science and Technology (SUSTech), Shenzhen, China
| | - Chunhui Hou
- Department of Biology, Southern University of Science and Technology (SUSTech), Shenzhen, China
| | - Shian Wu
- State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin, P.R. China
| | - Yu Chung Tse
- Department of Biology, Southern University of Science and Technology (SUSTech), Shenzhen, China .,Guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research, Shenzhen Key Laboratory of Cell Microenvironment, SUSTech, Shenzhen, China
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24
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Syncytial germline architecture is actively maintained by contraction of an internal actomyosin corset. Nat Commun 2018; 9:4694. [PMID: 30410005 PMCID: PMC6224597 DOI: 10.1038/s41467-018-07149-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 10/09/2018] [Indexed: 01/13/2023] Open
Abstract
Syncytial architecture is an evolutionarily-conserved feature of the germline of many species and plays a crucial role in their fertility. However, the mechanism supporting syncytial organization is largely unknown. Here, we identify a corset-like actomyosin structure within the syncytial germline of Caenorhabditis elegans, surrounding the common rachis. Using laser microsurgery, we demonstrate that actomyosin contractility within this structure generates tension both in the plane of the rachis surface and perpendicular to it, opposing membrane tension. Genetic and pharmacological perturbations, as well as mathematical modeling, reveal a balance of forces within the gonad and show how changing the tension within the actomyosin corset impinges on syncytial germline structure, leading, in extreme cases, to sterility. Thus, our work highlights a unique tissue-level cytoskeletal structure, and explains the critical role of actomyosin contractility in the preservation of a functional germline. Germline cells in many species are fused to form a syncytium but the mechanics behind the maintenance of these structures are poorly defined. Here, the authors propose an inner contractile actomyosin corset provides a supportive framework to maintain germline architecture in C. elegans.
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Seidel HS, Smith TA, Evans JK, Stamper JQ, Mast TG, Kimble J. C. elegans germ cells divide and differentiate in a folded tissue. Dev Biol 2018; 442:173-187. [DOI: 10.1016/j.ydbio.2018.07.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2018] [Revised: 07/08/2018] [Accepted: 07/16/2018] [Indexed: 12/18/2022]
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Abstract
Cerebral cavernous malformations (CCM) are manifested by microvascular lesions characterized by leaky endothelial cells with minimal intervening parenchyma predominantly in the central nervous system predisposed to hemorrhagic stroke, resulting in focal neurological defects. Till date, three proteins are implicated in this condition: CCM1 (KRIT1), CCM2 (MGC4607), and CCM3 (PDCD10). These multi-domain proteins form a protein complex via CCM2 that function as a docking site for the CCM signaling complex, which modulates many signaling pathways. Defects in the formation of this signaling complex have been shown to affect a wide range of cellular processes including cell-cell contact stability, vascular angiogenesis, oxidative damage protection and multiple biogenic events. In this review we provide an update on recent advances in structure and function of these CCM proteins, especially focusing on the signaling cascades involved in CCM pathogenesis and the resultant CCM cellular phenotypes in the past decade.
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Affiliation(s)
- Akhil Padarti
- Department of Biomedical Sciences, Texas Tech University Health Science Center El Paso, El Paso, TX 79905, USA
| | - Jun Zhang
- Department of Biomedical Sciences, Texas Tech University Health Science Center El Paso, El Paso, TX 79905, USA
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Lee KY, Green RA, Gutierrez E, Gomez-Cavazos JS, Kolotuev I, Wang S, Desai A, Groisman A, Oegema K. CYK-4 functions independently of its centralspindlin partner ZEN-4 to cellularize oocytes in germline syncytia. eLife 2018; 7:36919. [PMID: 29989548 PMCID: PMC6056237 DOI: 10.7554/elife.36919] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 07/09/2018] [Indexed: 12/15/2022] Open
Abstract
Throughout metazoans, germ cells undergo incomplete cytokinesis to form syncytia connected by intercellular bridges. Gamete formation ultimately requires bridge closure, yet how bridges are reactivated to close is not known. The most conserved bridge component is centralspindlin, a complex of the Rho family GTPase-activating protein (GAP) CYK-4/MgcRacGAP and the microtubule motor ZEN-4/kinesin-6. Here, we show that oocyte production by the syncytial Caenorhabditis elegans germline requires CYK-4 but not ZEN-4, which contrasts with cytokinesis, where both are essential. Longitudinal imaging after conditional inactivation revealed that CYK-4 activity is important for oocyte cellularization, but not for the cytokinesis-like events that generate syncytial compartments. CYK-4’s lipid-binding C1 domain and the GTPase-binding interface of its GAP domain were both required to target CYK-4 to intercellular bridges and to cellularize oocytes. These results suggest that the conserved C1-GAP region of CYK-4 constitutes a targeting module required for closure of intercellular bridges in germline syncytia.
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Affiliation(s)
- Kian-Yong Lee
- Ludwig Institute for Cancer Research, Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, United States
| | - Rebecca A Green
- Ludwig Institute for Cancer Research, Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, United States
| | - Edgar Gutierrez
- Department of Physics, University of California, San Diego, La Jolla, United States
| | - J Sebastian Gomez-Cavazos
- Ludwig Institute for Cancer Research, Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, United States
| | - Irina Kolotuev
- Microscopy Rennes Imaging Center and Biosit, University of Rennes 1, Rennes, France
| | - Shaohe Wang
- Ludwig Institute for Cancer Research, Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, United States
| | - Arshad Desai
- Ludwig Institute for Cancer Research, Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, United States
| | - Alex Groisman
- Department of Physics, University of California, San Diego, La Jolla, United States
| | - Karen Oegema
- Ludwig Institute for Cancer Research, Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, United States
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Kline A, Curry T, Lewellyn L. The Misshapen kinase regulates the size and stability of the germline ring canals in the Drosophila egg chamber. Dev Biol 2018; 440:99-112. [PMID: 29753016 DOI: 10.1016/j.ydbio.2018.05.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 04/06/2018] [Accepted: 05/08/2018] [Indexed: 11/30/2022]
Abstract
Intercellular bridges are conserved structures that allow neighboring cells to exchange cytoplasmic material; defects in intercellular bridges can lead to infertility in many organisms. Here, we use the Drosophila egg chamber to study the mechanisms that regulate intercellular bridges. Within the developing egg chamber, the germ cells (15 nurse cells and 1 oocyte) are connected to each other through intercellular bridges called ring canals, which expand over the course of oogenesis to support the transfer of materials from the nurse cells to the oocyte. The ring canals are enriched in actin and actin binding proteins, and many proteins have been identified that localize to the germline ring canals and control their expansion and stability. Here, we demonstrate a novel role for the Ste20 family kinase, Misshapen (Msn), in regulation of the size of the germline ring canals. Msn localizes to ring canals throughout most of oogenesis, and depletion of Msn led to the formation of larger ring canals. Over-expression of Msn decreased ring canal diameter, and expression of a membrane tethered form of Msn caused ring canal detachment and nurse cell fusion. Altering the levels or localization of Msn also led to changes in the actin cytoskeleton and altered the localization of E-cadherin, which suggests that Msn could be indirectly limiting ring canal size by altering the structure or dynamics of the actin cytoskeleton and/or adherens junctions.
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Affiliation(s)
- Ashley Kline
- Department of Biological Sciences, Butler University, Indianapolis, IN 46208, USA
| | - Travis Curry
- Department of Biological Sciences, Butler University, Indianapolis, IN 46208, USA
| | - Lindsay Lewellyn
- Department of Biological Sciences, Butler University, Indianapolis, IN 46208, USA.
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30
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Świątek P, de Wit P, Jarosz N, Chajec Ł, Urbisz AZ. Micromorphology of ovaries and oogenesis in Grania postclitellochaeta (Clitellata: Enchytraeidae). ZOOLOGY 2018; 126:119-127. [DOI: 10.1016/j.zool.2017.11.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 11/13/2017] [Accepted: 11/13/2017] [Indexed: 01/24/2023]
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31
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Descovich CP, Cortes DB, Ryan S, Nash J, Zhang L, Maddox PS, Nedelec F, Maddox AS. Cross-linkers both drive and brake cytoskeletal remodeling and furrowing in cytokinesis. Mol Biol Cell 2017; 29:622-631. [PMID: 29282285 PMCID: PMC6004588 DOI: 10.1091/mbc.e17-06-0392] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 12/14/2017] [Accepted: 12/19/2017] [Indexed: 11/16/2022] Open
Abstract
Cell shape changes such as cytokinesis are driven by the actomyosin contractile cytoskeleton. The molecular rearrangements that bring about contractility in nonmuscle cells are currently debated. Specifically, both filament sliding by myosin motors, as well as cytoskeletal cross-linking by myosins and nonmotor cross-linkers, are thought to promote contractility. Here we examined how the abundance of motor and nonmotor cross-linkers affects the speed of cytokinetic furrowing. We built a minimal model to simulate contractile dynamics in the Caenorhabditis elegans zygote cytokinetic ring. This model predicted that intermediate levels of nonmotor cross-linkers are ideal for contractility; in vivo, intermediate levels of the scaffold protein anillin allowed maximal contraction speed. Our model also demonstrated a nonlinear relationship between the abundance of motor ensembles and contraction speed. In vivo, thorough depletion of nonmuscle myosin II delayed furrow initiation, slowed F-actin alignment, and reduced maximum contraction speed, but partial depletion allowed faster-than-expected kinetics. Thus, cytokinetic ring closure is promoted by moderate levels of both motor and nonmotor cross-linkers but attenuated by an over-abundance of motor and nonmotor cross-linkers. Together, our findings extend the growing appreciation for the roles of cross-linkers in cytokinesis and reveal that they not only drive but also brake cytoskeletal remodeling.
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Affiliation(s)
- Carlos Patino Descovich
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 32377.,Department of Pathology & Laboratory Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 32377
| | - Daniel B Cortes
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 32377
| | - Sean Ryan
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 32377
| | - Jazmine Nash
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 32377
| | - Li Zhang
- Institute for Research in Immunology and Cancer, University of Montréal, Montréal, QC H3C 3T5, Canada
| | - Paul S Maddox
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 32377
| | - Francois Nedelec
- Cell Biology and Biophysics Unit, EMBL, 69117 Heidelberg, Germany
| | - Amy Shaub Maddox
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 32377
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Goupil E, Amini R, Hall DH, Labbé JC. Actomyosin contractility regulators stabilize the cytoplasmic bridge between the two primordial germ cells during Caenorhabditis elegans embryogenesis. Mol Biol Cell 2017; 28:3789-3800. [PMID: 29074566 PMCID: PMC5739295 DOI: 10.1091/mbc.e17-08-0502] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 10/18/2017] [Accepted: 10/20/2017] [Indexed: 01/08/2023] Open
Abstract
The Caenorhabditis elegans germline is syncytial but its formation is not completely understood. During embryogenesis, the germline precursor blastomere does not complete cytokinesis and maintains a stable cytoplasmic bridge between the two primordial germ cells that is enriched in actomyosin contractility regulators. Stable cytoplasmic bridges arise from failed cytokinesis, the last step of cell division, and are a key feature of syncytial architectures in the germline of most metazoans. Whereas the Caenorhabditis elegans germline is syncytial, its formation remains poorly understood. We found that the germline precursor blastomere, P4, fails cytokinesis, leaving a stable cytoplasmic bridge between the two daughter cells, Z2 and Z3. Depletion of several regulators of actomyosin contractility resulted in a regression of the membrane partition between Z2 and Z3, indicating that they are required to stabilize the cytoplasmic bridge. Epistatic analysis revealed a pathway in which Rho regulators promote accumulation of the noncannonical anillin ANI-2 at the stable cytoplasmic bridge, which in turns promotes the accumulation of the nonmuscle myosin II NMY-2 and the midbody component CYK-7 at the bridge, in part by limiting the accumulation of canonical anillin ANI-1. Our results uncover key steps in C. elegans germline formation and define a set of conserved regulators that are enriched at the primordial germ cell cytoplasmic bridge to ensure its stability during embryonic development.
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Affiliation(s)
| | - Rana Amini
- Institute of Research in Immunology and Cancer and
| | - David H Hall
- Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461
| | - Jean-Claude Labbé
- Institute of Research in Immunology and Cancer and .,Department of Pathology and Cell Biology, Université de Montréal, Montréal, QC H3C 3J7, Canada
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Pal S, Lant B, Yu B, Tian R, Tong J, Krieger JR, Moran MF, Gingras AC, Derry WB. CCM-3 Promotes C. elegans Germline Development by Regulating Vesicle Trafficking Cytokinesis and Polarity. Curr Biol 2017; 27:868-876. [DOI: 10.1016/j.cub.2017.02.028] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 02/01/2017] [Accepted: 02/13/2017] [Indexed: 10/20/2022]
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