1
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Miller SG, Hoh M, Ebmeier CC, Tay JW, Ahn NG. Cooperative polarization of MCAM/CD146 and ERM family proteins in melanoma. Mol Biol Cell 2024; 35:ar31. [PMID: 38117590 PMCID: PMC10916866 DOI: 10.1091/mbc.e23-06-0255] [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: 06/28/2023] [Revised: 11/22/2023] [Accepted: 12/15/2023] [Indexed: 12/22/2023] Open
Abstract
The WRAMP structure is a protein network associated with tail-end actomyosin contractility, membrane retraction, and directional persistence during cell migration. A marker of WRAMP structures is melanoma cell adhesion molecule (MCAM) which dynamically polarizes to the cell rear. However, factors that mediate MCAM polarization are still unknown. In this study, BioID using MCAM as bait identifies the ERM family proteins, moesin, ezrin, and radixin, as WRAMP structure components. We also present a novel image analysis pipeline, Protein Polarity by Percentile ("3P"), which classifies protein polarization using machine learning and facilitates quantitative analysis. Using 3P, we find that depletion of moesin, and to a lesser extent ezrin, decreases the proportion of cells with polarized MCAM. Furthermore, although copolarized MCAM and ERM proteins show high spatial overlap, 3P identifies subpopulations with ERM proteins closer to the cell periphery. Live-cell imaging confirms that MCAM and ERM protein polarization is tightly coordinated, but ERM proteins enrich at the cell edge first. Finally, deletion of a juxtamembrane segment in MCAM previously shown to promote ERM protein interactions impedes MCAM polarization. Our findings highlight the requirement for ERM proteins in recruitment of MCAM to WRAMP structures and an advanced computational tool to characterize protein polarization.
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Affiliation(s)
- Suzannah G. Miller
- Department of Biochemistry, University of Colorado Boulder, Boulder CO 80303
| | - Maria Hoh
- Department of Biochemistry, University of Colorado Boulder, Boulder CO 80303
| | | | - Jian Wei Tay
- BioFrontiers Institute, University of Colorado Boulder, Boulder CO 80303
| | - Natalie G. Ahn
- Department of Biochemistry, University of Colorado Boulder, Boulder CO 80303
- BioFrontiers Institute, University of Colorado Boulder, Boulder CO 80303
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2
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Čada Š, Bryja V. Local Wnt signalling in the asymmetric migrating vertebrate cells. Semin Cell Dev Biol 2021; 125:26-36. [PMID: 34896020 DOI: 10.1016/j.semcdb.2021.11.020] [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: 08/25/2021] [Revised: 11/18/2021] [Accepted: 11/19/2021] [Indexed: 11/27/2022]
Abstract
Wnt signalling is known to generate cellular asymmetry via Wnt/planar cell polarity pathway (Wnt/PCP). Wnt/PCP acts locally (i) to orient membrane polarity and asymmetric establishment of intercellular junctions via conserved set of PCP proteins most specifically represented by Vangl and Prickle, and (ii) to asymmetrically rearrange cytoskeletal structures via downstream effectors of Dishevelled (Dvl). This process is best described on stable phenotypes of epithelial cells. Here, however, we review the activity of Wnt signalling in migratory cells which experience the extensive rearrangements of cytoskeleton and consequently dynamic asymmetry, making the localised effects of Wnt signalling easier to distinguish. Firstly, we focused on migration of neuronal axons, which allows to study how the pre-existent cellular asymmetry can influence Wnt signalling outcome. Then, we reviewed the role of Wnt signalling in models of mesenchymal migration including neural crest, melanoma, and breast cancer cells. Last, we collected evidence for local Wnt signalling in amoeboid cells, especially lymphocytes. As the outcome of this review, we identify blank spots in our current understanding of this topic, propose models that synthesise the current observations and allow formulation of testable hypotheses for the future research.
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Affiliation(s)
- Štěpán Čada
- Department of Experimental Biology, Faculty of Science, Masaryk University, Kamenice 5, 62500 Brno, Czech Republic
| | - Vítězslav Bryja
- Department of Experimental Biology, Faculty of Science, Masaryk University, Kamenice 5, 62500 Brno, Czech Republic; Department of Cytokinetics, Institute of Biophysics CAS, Královopolská 135, 61265 Brno, Czech Republic.
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3
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Radaszkiewicz T, Nosková M, Gömöryová K, Vondálová Blanářová O, Radaszkiewicz KA, Picková M, Víchová R, Gybeľ T, Kaiser K, Demková L, Kučerová L, Bárta T, Potěšil D, Zdráhal Z, Souček K, Bryja V. RNF43 inhibits WNT5A-driven signaling and suppresses melanoma invasion and resistance to the targeted therapy. eLife 2021; 10:65759. [PMID: 34702444 PMCID: PMC8550759 DOI: 10.7554/elife.65759] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 09/28/2021] [Indexed: 12/30/2022] Open
Abstract
RNF43 is an E3 ubiquitin ligase and known negative regulator of WNT/β-catenin signaling. We demonstrate that RNF43 is also a regulator of noncanonical WNT5A-induced signaling in human cells. Analysis of the RNF43 interactome using BioID and immunoprecipitation showed that RNF43 can interact with the core receptor complex components dedicated to the noncanonical Wnt pathway such as ROR1, ROR2, VANGL1, and VANGL2. RNF43 triggers VANGL2 ubiquitination and proteasomal degradation and clathrin-dependent internalization of ROR1 receptor and inhibits ROR2 activation. These activities of RNF43 are physiologically relevant and block pro-metastatic WNT5A signaling in melanoma. RNF43 inhibits responses to WNT5A, which results in the suppression of invasive properties of melanoma cells. Furthermore, RNF43 prevented WNT5A-assisted development of resistance to BRAF V600E and MEK inhibitors. Next, RNF43 acted as melanoma suppressor and improved response to targeted therapies in vivo. In line with these findings, RNF43 expression decreases during melanoma progression and RNF43-low patients have a worse prognosis. We conclude that RNF43 is a newly discovered negative regulator of WNT5A-mediated biological responses that desensitizes cells to WNT5A.
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Affiliation(s)
- Tomasz Radaszkiewicz
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Michaela Nosková
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Kristína Gömöryová
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Olga Vondálová Blanářová
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | | | - Markéta Picková
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic.,Department of Cytokinetics, Institute of Biophysics CAS, Brno, Czech Republic.,International Clinical Research Center FNUSA-ICRC, Brno, Czech Republic
| | - Ráchel Víchová
- Department of Cytokinetics, Institute of Biophysics CAS, Brno, Czech Republic
| | - Tomáš Gybeľ
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Karol Kaiser
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Lucia Demková
- Laboratory of Molecular Oncology, Cancer Research Institute, Biomedical Research Center of the Slovak Academy of Sciences, Bratislava, Slovakia
| | - Lucia Kučerová
- Laboratory of Molecular Oncology, Cancer Research Institute, Biomedical Research Center of the Slovak Academy of Sciences, Bratislava, Slovakia
| | - Tomáš Bárta
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic.,Department of Histology and Embryology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - David Potěšil
- Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Zbyněk Zdráhal
- Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Karel Souček
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic.,Department of Cytokinetics, Institute of Biophysics CAS, Brno, Czech Republic.,International Clinical Research Center FNUSA-ICRC, Brno, Czech Republic
| | - Vítězslav Bryja
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic.,Department of Cytokinetics, Institute of Biophysics CAS, Brno, Czech Republic
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4
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Proteomic analysis identifies the E3 ubiquitin ligase Pdzrn3 as a regulatory target of Wnt5a-Ror signaling. Proc Natl Acad Sci U S A 2021; 118:2104944118. [PMID: 34135125 DOI: 10.1073/pnas.2104944118] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Wnt5a-Ror signaling is a conserved pathway that regulates morphogenetic processes during vertebrate development [R. T. Moon et al, Development 119, 97-111 (1993); I. Oishi et al, Genes Cells 8, 645-654 (2003)], but its downstream signaling events remain poorly understood. Through a large-scale proteomic screen in mouse embryonic fibroblasts, we identified the E3 ubiquitin ligase Pdzrn3 as a regulatory target of the Wnt5a-Ror pathway. Upon pathway activation, Pdzrn3 is degraded in a β-catenin-independent, ubiquitin-proteasome system-dependent manner. We developed a flow cytometry-based reporter to monitor Pdzrn3 abundance and delineated a signaling cascade involving Frizzled, Dishevelled, Casein kinase 1, and Glycogen synthase kinase 3 that regulates Pdzrn3 stability. Epistatically, Pdzrn3 is regulated independently of Kif26b, another Wnt5a-Ror effector. Wnt5a-dependent degradation of Pdzrn3 requires phosphorylation of three conserved amino acids within its C-terminal LNX3H domain [M. Flynn, O. Saha, P. Young, BMC Evol. Biol. 11, 235 (2011)], which acts as a bona fide Wnt5a-responsive element. Importantly, this phospho-dependent degradation is essential for Wnt5a-Ror modulation of cell migration. Collectively, this work establishes a Wnt5a-Ror cell morphogenetic cascade involving Pdzrn3 phosphorylation and degradation.
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5
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Cheung SY, Sayeed M, Nakuluri K, Li L, Feldman BJ. MYH9 facilitates autoregulation of adipose tissue depot development. JCI Insight 2021; 6:136233. [PMID: 33986190 PMCID: PMC8262332 DOI: 10.1172/jci.insight.136233] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 03/31/2021] [Indexed: 01/12/2023] Open
Abstract
White adipose tissue not only serves as a reservoir for energy storage but also secretes a variety of hormonal signals and modulates systemic metabolism. A substantial amount of adipose tissue develops in early postnatal life, providing exceptional access to the formation of this important tissue. Although a number of factors have been identified that can modulate the differentiation of progenitor cells into mature adipocytes in cell-autonomous assays, it remains unclear which are connected to physiological extracellular inputs and are most relevant to tissue formation in vivo. Here, we elucidate that mature adipocytes themselves signal to adipose depot–resident progenitor cells to direct depot formation in early postnatal life and gate adipogenesis when the tissue matures. Our studies revealed that as the adipose depot matures, a signal generated in mature adipocytes is produced, converges on progenitor cells to regulate the cytoskeletal protein MYH9, and attenuates the rate of adipogenesis in vivo.
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Affiliation(s)
| | | | | | | | - Brian J Feldman
- Department of Pediatrics.,Nutrition Obesity Research Center.,Diabetes Research Center, and.,Developmental and Stem Cell Biology Program, University of California, San Francisco, San Francisco, California, USA
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6
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Guo S, Meng L, Liu H, Yuan L, Zhao N, Ni J, Zhang Y, Ben J, Li YP, Ma J. Trio cooperates with Myh9 to regulate neural crest-derived craniofacial development. Am J Cancer Res 2021; 11:4316-4334. [PMID: 33754063 PMCID: PMC7977452 DOI: 10.7150/thno.51745] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2020] [Accepted: 02/07/2021] [Indexed: 02/06/2023] Open
Abstract
Trio is a unique member of the Rho-GEF family that has three catalytic domains and is vital for various cellular processes in both physiological and developmental settings. TRIO mutations in humans are involved in craniofacial abnormalities, in which patients present with mandibular retrusion. However, little is known about the molecular mechanisms of Trio in neural crest cell (NCC)-derived craniofacial development, and there is still a lack of direct evidence to assign a functional role to Trio in NCC-induced craniofacial abnormalities. Methods: In vivo, we used zebrafish and NCC-specific knockout mouse models to investigate the phenotype and dynamics of NCC development in Trio morphants. In vitro, iTRAQ, GST pull-down assays, and proximity ligation assay (PLA) were used to explore the role of Trio and its potential downstream mediators in NCC migration and differentiation. Results: In zebrafish and mouse models, disruption of Trio elicited a migration deficit and impaired the differentiation of NCC derivatives, leading to craniofacial growth deficiency and mandibular retrusion. Moreover, Trio positively regulated Myh9 expression and directly interacted with Myh9 to coregulate downstream cellular signaling in NCCs. We further demonstrated that disruption of Trio or Myh9 inhibited Rac1 and Cdc42 activity, specifically affecting the nuclear export of β-catenin and NCC polarization. Remarkably, craniofacial abnormalities caused by trio deficiency in zebrafish could be partially rescued by the injection of mRNA encoding myh9, ca-Rac1, or ca-Cdc42. Conclusions: Here, we identified that Trio, interacting mostly with Myh9, acts as a key regulator of NCC migration and differentiation during craniofacial development. Our results indicate that trio morphant zebrafish and Wnt1-cre;Triofl/fl mice offer potential model systems to facilitate the study of the pathogenic mechanisms of Trio mutations causing craniofacial abnormalities.
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7
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Affiliation(s)
- Valerie Marie Weaver
- Surgery, Bioengineering and Tissue Regeneration, University of California, San Francisco, San Francisco, CA 94143
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8
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Nonmuscle myosin IIA and IIB differentially contribute to intrinsic and directed migration of human embryonic lung fibroblasts. Biochem Biophys Res Commun 2018; 498:25-31. [DOI: 10.1016/j.bbrc.2018.02.171] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Accepted: 02/22/2018] [Indexed: 11/19/2022]
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9
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Moreno-Fortuny A, Bragg L, Cossu G, Roostalu U. MCAM contributes to the establishment of cell autonomous polarity in myogenic and chondrogenic differentiation. Biol Open 2017; 6:1592-1601. [PMID: 28923978 PMCID: PMC5703611 DOI: 10.1242/bio.027771] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Cell polarity has a fundamental role in shaping the morphology of cells and growing tissues. Polarity is commonly thought to be established in response to extracellular signals. Here we used a minimal in vitro assay that enabled us to monitor the determination of cell polarity in myogenic and chondrogenic differentiation in the absence of external signalling gradients. We demonstrate that the initiation of cell polarity is regulated by melanoma cell adhesion molecule (MCAM). We found highly polarized localization of MCAM, Moesin (MSN), Scribble (SCRIB) and Van-Gogh-like 2 (VANGL2) at the distal end of elongating myotubes. Knockout of MCAM or elimination of its endocytosis motif does not impair the initiation of myogenesis or myoblast fusion, but prevents myotube elongation. MSN, SCRIB and VANGL2 remain uniformly distributed in MCAM knockout cells. We show that MCAM is also required at early stages of chondrogenic differentiation. In both myogenic and chondrogenic differentiation MCAM knockout leads to transcriptional downregulation of Scrib and enhanced MAP kinase activity. Our data demonstrates the importance of cell autonomous polarity in differentiation. Summary: CD146/MCAM regulates cell autonomous polarization and asymmetric localization of Scribble, Van-Gogh-like 2 and Moesin, which is required in skeletal muscle myotube elongation and chondrocyte differentiation.
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Affiliation(s)
- Artal Moreno-Fortuny
- Manchester Academic Health Science Centre, Division of Extracellular Matrix and Regenerative Medicine, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PL, UK
| | - Laricia Bragg
- Manchester Academic Health Science Centre, Division of Extracellular Matrix and Regenerative Medicine, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PL, UK
| | - Giulio Cossu
- Manchester Academic Health Science Centre, Division of Extracellular Matrix and Regenerative Medicine, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PL, UK
| | - Urmas Roostalu
- Manchester Academic Health Science Centre, Division of Extracellular Matrix and Regenerative Medicine, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PL, UK
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10
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Susman MW, Karuna EP, Kunz RC, Gujral TS, Cantú AV, Choi SS, Jong BY, Okada K, Scales MK, Hum J, Hu LS, Kirschner MW, Nishinakamura R, Yamada S, Laird DJ, Jao LE, Gygi SP, Greenberg ME, Ho HYH. Kinesin superfamily protein Kif26b links Wnt5a-Ror signaling to the control of cell and tissue behaviors in vertebrates. eLife 2017; 6:e26509. [PMID: 28885975 PMCID: PMC5590807 DOI: 10.7554/elife.26509] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 08/15/2017] [Indexed: 12/20/2022] Open
Abstract
Wnt5a-Ror signaling constitutes a developmental pathway crucial for embryonic tissue morphogenesis, reproduction and adult tissue regeneration, yet the molecular mechanisms by which the Wnt5a-Ror pathway mediates these processes are largely unknown. Using a proteomic screen, we identify the kinesin superfamily protein Kif26b as a downstream target of the Wnt5a-Ror pathway. Wnt5a-Ror, through a process independent of the canonical Wnt/β-catenin-dependent pathway, regulates the cellular stability of Kif26b by inducing its degradation via the ubiquitin-proteasome system. Through this mechanism, Kif26b modulates the migratory behavior of cultured mesenchymal cells in a Wnt5a-dependent manner. Genetic perturbation of Kif26b function in vivo caused embryonic axis malformations and depletion of primordial germ cells in the developing gonad, two phenotypes characteristic of disrupted Wnt5a-Ror signaling. These findings indicate that Kif26b links Wnt5a-Ror signaling to the control of morphogenetic cell and tissue behaviors in vertebrates and reveal a new role for regulated proteolysis in noncanonical Wnt5a-Ror signal transduction.
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Affiliation(s)
- Michael W Susman
- Department of NeurobiologyHarvard Medical SchoolBostonUnited States
| | - Edith P Karuna
- Department of Cell Biology and Human AnatomyUniversity of California, Davis School of MedicineDavisUnited States
| | - Ryan C Kunz
- Department of Cell BiologyHarvard Medical SchoolBostonUnited States
| | - Taranjit S Gujral
- Department of Systems BiologyHarvard Medical SchoolBostonUnited States
- Division of Human BiologyFred Hutchinson Cancer Research CenterSeattleUnited States
| | - Andrea V Cantú
- Department of Obstetrics, Gynecology and Reproductive SciencesCenter for Reproductive Sciences, Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of CaliforniaSan FranciscoUnited States
| | - Shannon S Choi
- Department of Cell Biology and Human AnatomyUniversity of California, Davis School of MedicineDavisUnited States
| | - Brigette Y Jong
- Department of Cell Biology and Human AnatomyUniversity of California, Davis School of MedicineDavisUnited States
| | - Kyoko Okada
- Department of Cell Biology and Human AnatomyUniversity of California, Davis School of MedicineDavisUnited States
| | - Michael K Scales
- Department of Cell Biology and Human AnatomyUniversity of California, Davis School of MedicineDavisUnited States
| | - Jennie Hum
- Department of Cell Biology and Human AnatomyUniversity of California, Davis School of MedicineDavisUnited States
| | - Linda S Hu
- Department of NeurobiologyHarvard Medical SchoolBostonUnited States
| | - Marc W Kirschner
- Department of Systems BiologyHarvard Medical SchoolBostonUnited States
| | - Ryuichi Nishinakamura
- Department of Kidney DevelopmentInstitute of Molecular Embryology and Genetics, Kumamoto UniversityKumamotoJapan
| | - Soichiro Yamada
- Department of Biomedical EngineeringUniversity of CaliforniaDavisUnited States
| | - Diana J Laird
- Department of Obstetrics, Gynecology and Reproductive SciencesCenter for Reproductive Sciences, Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of CaliforniaSan FranciscoUnited States
| | - Li-En Jao
- Department of Cell Biology and Human AnatomyUniversity of California, Davis School of MedicineDavisUnited States
| | - Steven P Gygi
- Department of Cell BiologyHarvard Medical SchoolBostonUnited States
| | | | - Hsin-Yi Henry Ho
- Department of NeurobiologyHarvard Medical SchoolBostonUnited States
- Department of Cell Biology and Human AnatomyUniversity of California, Davis School of MedicineDavisUnited States
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11
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Stires JC, Latz MI. Contribution of the cytoskeleton to mechanosensitivity reported by dinoflagellate bioluminescence. Cytoskeleton (Hoboken) 2017; 75:12-21. [PMID: 28771965 DOI: 10.1002/cm.21392] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 07/12/2017] [Accepted: 08/01/2017] [Indexed: 01/24/2023]
Abstract
The cytoskeleton is crucial to cell mechanics and sensing the extracellular physical environment. The objective of this study was to examine the role of the cortical cytoskeleton in mechanosensitivity in a unicellular protist, the marine dinoflagellate Lingulodinium polyedra, using its intrinsic bioluminescence as a rapid reporter of mechanotransduction. Pharmacological treatments resolved effects due to immediate cytoskeleton disruption from those due to cytoskeletal remodeling during the light to dark phase transition. The cytoskeleton was visualized by confocal laser scanning microscopy of immunohistochemically labeled microtubules and phalloidin labeled F-actin, and mechanosensitivity assessed based on the bioluminescence response to mechanical stimulation measured during the dark phase. Latrunculin B treatment after the transition from the light to dark phase resulted in some disruption of cortical F-actin, no observed effect on the cortical microtubules, and partial inhibition of the bioluminescence response. Treatment with oryzalin, which depolarizes microtubules, completely disrupted the microtubule network and cortical F-actin, and partially inhibited bioluminescence. These results demonstrate that cells retain some mechanosensitivity despite a disrupted cytoskeleton; link mechanosensitivity to intact F-actin; show a close connection between F-actin and microtubules comprising the cortical cytoskeleton; confirm a strong contribution of the actin cytoskeleton to the translocation of scintillons, vesicles containing the luminescent chemistry; and support the role of the actin cytoskeleton in the association of scintillons with the vacuole membrane.
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Affiliation(s)
- J C Stires
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, 92039
| | - M I Latz
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, 92039
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