1
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Sakamuri SSVP, Sure VN, Oruganti L, Wisen W, Chandra PK, Liu N, Fonseca VA, Wang X, Klein J, Katakam PVG. Acute severe hypoglycemia alters mouse brain microvascular proteome. J Cereb Blood Flow Metab 2024; 44:556-572. [PMID: 37944245 PMCID: PMC10981402 DOI: 10.1177/0271678x231212961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 09/12/2023] [Accepted: 10/05/2023] [Indexed: 11/12/2023]
Abstract
Hypoglycemia increases the risk related to stroke and neurodegenerative diseases, however, the underlying mechanisms are unclear. For the first time, we studied the effect of a single episode (acute) of severe (ASH) and mild (AMH) hypoglycemia on mouse brain microvascular proteome. After four-hour fasting, insulin was administered (i.p) to lower mean blood glucose in mice and induce ∼30 minutes of ASH (∼30 mg/dL) or AMH (∼75 mg/dL), whereas a similar volume of saline was given to control mice (∼130 mg/dL). Blood glucose was allowed to recover over 60 minutes either spontaneously or by 20% dextrose administration (i.p). Twenty-four hours later, the brain microvessels (BMVs) were isolated, and tandem mass tag (TMT)-based quantitative proteomics was performed using liquid chromatography-mass spectrometry (LC/MS). When compared to control, ASH significantly downregulated 13 proteins (p ≤ 0.05) whereas 23 proteins showed a strong trend toward decrease (p ≤ 0.10). When compared to AMH, ASH significantly induced the expression of 35 proteins with 13 proteins showing an increasing trend. AMH downregulated only 3 proteins. ASH-induced downregulated proteins are involved in actin cytoskeleton maintenance needed for cell shape and migration which are critical for blood-brain barrier maintenance and angiogenesis. In contrast, ASH-induced upregulated proteins are RNA-binding proteins involved in RNA splicing, transport, and stability. Thus, ASH alters BMV proteomics to impair cytoskeletal integrity and RNA processing which are critical for cerebrovascular function.
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Affiliation(s)
- Siva SVP Sakamuri
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Venkata N Sure
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Lokanatha Oruganti
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA
| | - William Wisen
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Partha K Chandra
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA
- Neuroscience Program, Tulane Brain Institute, Tulane University, New Orleans, LA, USA
| | - Ning Liu
- Neuroscience Program, Tulane Brain Institute, Tulane University, New Orleans, LA, USA
- Clinical Neuroscience Research Center, New Orleans, LA, USA
- Department of Neurosurgery, Tulane University School of Medicine, New Orleans, LA, USA
| | - Vivian A Fonseca
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA
- Department of Medicine, Tulane University School of Medicine, New Orleans, LA, USA
| | - Xiaoying Wang
- Neuroscience Program, Tulane Brain Institute, Tulane University, New Orleans, LA, USA
- Clinical Neuroscience Research Center, New Orleans, LA, USA
- Department of Neurosurgery, Tulane University School of Medicine, New Orleans, LA, USA
| | - Jennifer Klein
- Department of Biochemistry & Molecular Biology, Louisiana State University School of Medicine, New Orleans, LA, USA
| | - Prasad VG Katakam
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA
- Neuroscience Program, Tulane Brain Institute, Tulane University, New Orleans, LA, USA
- Clinical Neuroscience Research Center, New Orleans, LA, USA
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2
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Henderson JM, Ljubojevic N, Belian S, Chaze T, Castaneda D, Battistella A, Giai Gianetto Q, Matondo M, Descroix S, Bassereau P, Zurzolo C. Tunnelling nanotube formation is driven by Eps8/IRSp53-dependent linear actin polymerization. EMBO J 2023; 42:e113761. [PMID: 38009333 PMCID: PMC10711657 DOI: 10.15252/embj.2023113761] [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: 02/13/2023] [Revised: 10/27/2023] [Accepted: 11/02/2023] [Indexed: 11/28/2023] Open
Abstract
Tunnelling nanotubes (TNTs) connect distant cells and mediate cargo transfer for intercellular communication in physiological and pathological contexts. How cells generate these actin-mediated protrusions to span lengths beyond those attainable by canonical filopodia remains unknown. Through a combination of micropatterning, microscopy, and optical tweezer-based approaches, we demonstrate that TNTs formed through the outward extension of actin achieve distances greater than the mean length of filopodia and that branched Arp2/3-dependent pathways attenuate the extent to which actin polymerizes in nanotubes, thus limiting their occurrence. Proteomic analysis using epidermal growth factor receptor kinase substrate 8 (Eps8) as a positive effector of TNTs showed that, upon Arp2/3 inhibition, proteins enhancing filament turnover and depolymerization were reduced and Eps8 instead exhibited heightened interactions with the inverted Bin/Amphiphysin/Rvs (I-BAR) domain protein IRSp53 that provides a direct connection with linear actin polymerases. Our data reveals how common protrusion players (Eps8 and IRSp53) form tunnelling nanotubes, and that when competing pathways overutilizing such proteins and monomeric actin in Arp2/3 networks are inhibited, processes promoting linear actin growth dominate to favour tunnelling nanotube formation.
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Affiliation(s)
- J Michael Henderson
- Membrane Traffic and Pathogenesis Unit, Department of Cell Biology and InfectionCNRS UMR 3691, Université de Paris, Institut PasteurParisFrance
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR 168, Laboratoire Physico‐Chimie CurieParisFrance
- Present address:
Department of ChemistryBowdoin CollegeBrunswickMEUSA
| | - Nina Ljubojevic
- Membrane Traffic and Pathogenesis Unit, Department of Cell Biology and InfectionCNRS UMR 3691, Université de Paris, Institut PasteurParisFrance
- Sorbonne UniversitéParisFrance
| | - Sevan Belian
- Membrane Traffic and Pathogenesis Unit, Department of Cell Biology and InfectionCNRS UMR 3691, Université de Paris, Institut PasteurParisFrance
- Université Paris‐SaclayGif‐sur‐YvetteFrance
| | - Thibault Chaze
- Proteomics Platform, Mass Spectrometry for Biology Unit, CNRS USR 2000, Institut PasteurParisFrance
| | - Daryl Castaneda
- Membrane Traffic and Pathogenesis Unit, Department of Cell Biology and InfectionCNRS UMR 3691, Université de Paris, Institut PasteurParisFrance
- Keele UniversityKeeleUK
| | - Aude Battistella
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR 168, Laboratoire Physico‐Chimie CurieParisFrance
| | - Quentin Giai Gianetto
- Proteomics Platform, Mass Spectrometry for Biology Unit, CNRS USR 2000, Institut PasteurParisFrance
- Bioinformatics and Biostatistics Hub, Computational Biology DepartmentCNRS USR 3756, Institut PasteurParisFrance
| | - Mariette Matondo
- Proteomics Platform, Mass Spectrometry for Biology Unit, CNRS USR 2000, Institut PasteurParisFrance
| | - Stéphanie Descroix
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR 168, Laboratoire Physico‐Chimie CurieParisFrance
- Institut Pierre‐Gilles de GennesParisFrance
| | - Patricia Bassereau
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR 168, Laboratoire Physico‐Chimie CurieParisFrance
| | - Chiara Zurzolo
- Membrane Traffic and Pathogenesis Unit, Department of Cell Biology and InfectionCNRS UMR 3691, Université de Paris, Institut PasteurParisFrance
- Department of Molecular Medicine and Medical BiotechnologyUniversity of Naples Federico IINaplesItaly
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3
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Li LY, Kreye J, Burek M, Cordero-Gomez C, Barthel PC, Sánchez-Sendín E, Kornau HC, Schmitz D, Scharf M, Meybohm P, Reincke SM, Prüss H, Höltje M. Brain blood vessel autoantibodies in patients with NMDA and GABA A receptor encephalitis: identification of unconventional Myosin-X as target antigen. Front Cell Neurosci 2023; 17:1077204. [PMID: 36794262 PMCID: PMC9922905 DOI: 10.3389/fncel.2023.1077204] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Accepted: 01/09/2023] [Indexed: 02/03/2023] Open
Abstract
Introduction: The antibody repertoire from CSF-derived antibody-secreting cells and memory B-cells in patients with encephalitis contains a considerable number of antibodies that do not target the disease-defining autoantigen such as the GABA or NMDA receptors. This study focuses on the functional relevance of autoantibodies to brain blood vessels in patients with GABAA and NMDA receptor encephalitis. Methods: We tested 149 human monoclonal IgG antibodies from the cerebrospinal fluid of six patients with different forms of autoimmune encephalitis on murine brain sections for reactivity to blood vessels using immunohistochemistry. Positive candidates were tested for reactivity with purified brain blood vessels, effects on transendothelial electrical resistance (TEER), and expression of tight junction proteins as well as gene regulation using human brain microvascular endothelial hCMEC/D3 cells as in vitro blood-brain barrier model. One blood-vessel reactive antibody was infused intrathecally by pump injection in mice to study in vivo binding and effects on tight junction proteins such as Occludin. Target protein identification was addressed using transfected HEK293 cells. Results: Six antibodies reacted with brain blood vessels, three were from the same patient with GABAAR encephalitis, and the other three were from different patients with NMDAR encephalitis. One antibody from an NMDAR encephalitis patient, mAb 011-138, also reacted with cerebellar Purkinje cells. In this case, treatment of hCMEC/D3 cells resulted in decreased TEER, reduced Occludin expression, and mRNA levels. Functional relevance in vivo was confirmed as Occludin downregulation was observed in mAb 011-138-infused animals. Unconventional Myosin-X was identified as a novel autoimmune target for this antibody. Discussion: We conclude that autoantibodies to blood vessels occur in autoimmune encephalitis patients and might contribute to a disruption of the blood-brain barrier thereby suggesting a potential pathophysiological relevance of these antibodies.
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Affiliation(s)
- Lucie Y. Li
- Institute of Integrative Neuroanatomy Berlin, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Jakob Kreye
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany,Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität Berlin and Berlin Institute of Health, Berlin, Germany,Department of Pediatric Neurology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Malgorzata Burek
- Department of Anaesthesiology, Intensive Care, Emergency and Pain Medicine, University Hospital Würzburg, Würzburg, Germany
| | - César Cordero-Gomez
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany,Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität Berlin and Berlin Institute of Health, Berlin, Germany
| | - Paula C. Barthel
- Institute of Integrative Neuroanatomy Berlin, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Elisa Sánchez-Sendín
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany,Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität Berlin and Berlin Institute of Health, Berlin, Germany
| | - Hans-Christian Kornau
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany,Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt- Universität zu Berlin and Berlin Institute of Health, Neuroscience Research Center, Berlin, Germany
| | - Dietmar Schmitz
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany,Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt- Universität zu Berlin and Berlin Institute of Health, Neuroscience Research Center, Berlin, Germany,Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany,Einstein Center for Neurosciences Berlin, Berlin, Germany,Bernstein Center for Computational Neuroscience Berlin, Berlin, Germany
| | - Madeleine Scharf
- Institute of Experimental Immunology, EUROIMMUN AG, Lübeck, Germany
| | - Patrick Meybohm
- Department of Anaesthesiology, Intensive Care, Emergency and Pain Medicine, University Hospital Würzburg, Würzburg, Germany
| | - S. Momsen Reincke
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany,Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität Berlin and Berlin Institute of Health, Berlin, Germany
| | - Harald Prüss
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany,Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität Berlin and Berlin Institute of Health, Berlin, Germany
| | - Markus Höltje
- Institute of Integrative Neuroanatomy Berlin, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany,*Correspondence: Markus Höltje
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4
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Brunet T, Booth DS. Cell polarity in the protist-to-animal transition. Curr Top Dev Biol 2023; 154:1-36. [PMID: 37100515 DOI: 10.1016/bs.ctdb.2023.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023]
Abstract
A signature feature of the animal kingdom is the presence of epithelia: sheets of polarized cells that both insulate the organism from its environment and mediate interactions with it. Epithelial cells display a marked apico-basal polarity, which is highly conserved across the animal kingdom, both in terms of morphology and of molecular regulators. How did this architecture first evolve? Although the last eukaryotic common ancestor almost certainly possessed a simple form of apico-basal polarity (marked by the presence of one or several flagella at a single cellular pole), comparative genomics and evolutionary cell biology reveal that the polarity regulators of animal epithelial cells have a surprisingly complex and stepwise evolutionary history. Here, we retrace their evolutionary assembly. We suggest that the "polarity network" that polarized animal epithelial cells evolved by integration of initially independent cellular modules that evolved at distinct steps of our evolutionary ancestry. The first module dates back to the last common ancestor of animals and amoebozoans and involved Par1, extracellular matrix proteins, and the integrin-mediated adhesion complex. Other regulators, such as Cdc42, Dlg, Par6 and cadherins evolved in ancient unicellular opisthokonts, and might have first been involved in F-actin remodeling and filopodial dynamics. Finally, the bulk of "polarity proteins" as well as specialized adhesion complexes evolved in the metazoan stem-line, in concert with the newly evolved intercellular junctional belts. Thus, the polarized architecture of epithelia can be understood as a palimpsest of components of distinct histories and ancestral functions, which have become tightly integrated in animal tissues.
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5
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Kim SJ, Sun EG, Bae JA, Park S, Hong CS, Park ZY, Kim H, Kim KK. A peptide interfering with the dimerization of oncogenic KITENIN protein and its stability suppresses colorectal tumour progression. Clin Transl Med 2022; 12:e871. [PMID: 35853101 PMCID: PMC9296036 DOI: 10.1002/ctm2.871] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 04/20/2022] [Accepted: 04/26/2022] [Indexed: 12/22/2022] Open
Abstract
The stability of a protein, as well as its function and versatility, can be enhanced through oligomerization. KITENIN (KAI1 C‐terminal interacting tetraspanin) is known to promote the malignant progression of colorectal cancer (CRC). How KITENIN maintains its structural integrity and stability are largely unknown, however. Here we investigated the mechanisms regulating the stability of KITENIN with the aim of developing therapeutics blocking its oncogenic functions. We found that KITENIN formed a homo‐oligomeric complex and that the intracellular C‐terminal domain (KITENIN‐CTD) was needed for this oligomerization. Expression of the KITENIN‐CTD alone interfered with the formation of the KITENIN homodimer, and the amino acid sequence from 463 to 471 within the KITENIN‐CTD was the most effective. This sequence coupled with a cell‐penetrating peptide was named a KITENIN dimerization‐interfering peptide (KDIP). We next studied the mechanisms by which KDIP affected the stability of KITENIN. The KITENIN‐interacting protein myosin‐X (Myo10), which has oncogenic activity in several cancers, functioned as an effector to stabilize the KITENIN homodimer in the cis formation. Treatment with KDIP resulted in the disintegration of the homodimer via downregulation of Myo10, which led to increased binding of RACK1 to the exposed RACK1‐interacting motif (463–471 aa), and subsequent autophagy‐dependent degradation of KITENIN and reduced CRC cell invasion. Intravenous injection of KDIP significantly reduced the tumour burden in a syngeneic mouse tumour model and colorectal liver metastasis in an intrasplenic hepatic metastasis model. Collectively, our present results provide a new cancer therapeutic peptide for blocking colorectal liver metastasis, which acts by inducing the downregulation of Myo10 and specifically targeting the stability of the oncogenic KITENIN protein.
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Affiliation(s)
- Sung Jin Kim
- Department of Pharmacology, Chonnam National University Medical School, Gwangju, Republic of Korea.,College of Pharmacy, Sunchon National University, Suncheon, Republic of Korea
| | - Eun Gene Sun
- Department of Pharmacology, Chonnam National University Medical School, Gwangju, Republic of Korea
| | - Jeong A Bae
- Department of Pharmacology, Chonnam National University Medical School, Gwangju, Republic of Korea
| | - Sehoon Park
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, Republic of Korea
| | - Chang-Soo Hong
- Department of Pharmacology, Chonnam National University Medical School, Gwangju, Republic of Korea
| | - Zee-Yong Park
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, Republic of Korea
| | - Hangun Kim
- College of Pharmacy, Sunchon National University, Suncheon, Republic of Korea
| | - Kyung Keun Kim
- Department of Pharmacology, Chonnam National University Medical School, Gwangju, Republic of Korea
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6
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Yang YF, Sun YY, Peters DM, Keller KE. The Effects of Mechanical Stretch on Integrins and Filopodial-Associated Proteins in Normal and Glaucomatous Trabecular Meshwork Cells. Front Cell Dev Biol 2022; 10:886706. [PMID: 35573666 PMCID: PMC9100841 DOI: 10.3389/fcell.2022.886706] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 04/11/2022] [Indexed: 01/29/2023] Open
Abstract
The trabecular meshwork (TM) is the tissue responsible for regulating aqueous humor fluid egress from the anterior eye. If drainage is impaired, intraocular pressure (IOP) becomes elevated, which is a primary risk factor for primary open angle glaucoma. TM cells sense elevated IOP via changes in their biomechanical environment. Filopodia cellular protrusions and integrin transmembrane proteins may play roles in detecting IOP elevation, yet this has not been studied in detail in the TM. Here, we investigate integrins and filopodial proteins, such as myosin-X (Myo10), in response to mechanical stretch, an in vitro technique that produces mechanical alterations mimicking elevated IOP. Pull-down assays showed Myo10 binding to α5 but not the β1 subunit, αvβ3, and αvβ5 integrins. Several of these integrins colocalized in nascent adhesions in the filopodial tip and shaft. Using conformation-specific antibodies, we found that β1 integrin, but not α5 or αvβ3 integrins, were activated following 1-h mechanical stretch. Cadherin -11 (CDH11), a cell adhesion molecule, did not bind to Myo10, but was associated with filopodia. Interestingly, CDH11 was downregulated on the TM cell surface following 1-h mechanical stretch. In glaucoma cells, CDH11 protein levels were increased. Finally, mechanical stretch caused a small, yet significant increase in Myo10 protein levels in glaucoma cells, but did not affect cellular communication of fluorescent vesicles via filopodia-like tunneling nanotubes. Together, these data suggest that TM cell adhesion proteins, β1 integrin and CDH11, have relatively rapid responses to mechanical stretch, which suggests a central role in sensing changes in IOP elevation in situ.
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Affiliation(s)
- Yong-Feng Yang
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, United States
| | - Ying Ying Sun
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, United States
| | - Donna M. Peters
- Department of Pathology and Laboratory Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Kate E. Keller
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, United States,Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR, United States,*Correspondence: Kate E. Keller,
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7
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Granados-Aparici S, Volodarsky-Perel A, Yang Q, Anam S, Tulandi T, Buckett W, Son WY, Younes G, Chung JT, Jin S, Terret MÉ, Clarke HJ. MYO10 promotes transzonal projection (TZP)-dependent germ line-somatic contact during mammalian folliculogenesis. Biol Reprod 2022; 107:474-487. [PMID: 35470858 PMCID: PMC9382396 DOI: 10.1093/biolre/ioac078] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 02/17/2022] [Accepted: 04/15/2022] [Indexed: 11/12/2022] Open
Abstract
Granulosa cells of growing ovarian follicles elaborate filopodia-like structures termed transzonal projections (TZPs) that supply the enclosed oocyte with factors essential for its development. Little is known, however, of the mechanisms underlying the generation of TZPs. We show in mouse and human that filopodia, defined by an actin backbone, emerge from granulosa cells in early-stage primary follicles and that actin-rich TZPs become detectable as soon as a space corresponding to the zona pellucida appears. mRNA encoding Myosin10 (MYO10), a motor protein that accumulates at the base and tips of filopodia and has been implicated in their initiation and elongation, is present in granulosa cells and oocytes of growing follicles. MYO10 protein accumulates in foci located mainly between the oocyte and innermost layer of granulosa cells, where it co-localizes with actin. In both mouse and human, the number of MYO10 foci increases as oocytes grow, corresponding to the increase in the number of actin-TZPs. RNAi-mediated depletion of MYO10 in cultured mouse granulosa cell-oocyte complexes is associated with a 52% reduction in the number of MYO10 foci and a 28% reduction in the number of actin-TZPs. Moreover, incubation of cumulus-oocyte complexes in the presence of epidermal growth factor, which triggers a 93% reduction in the number of actin-TZPs, is associated with a 55% reduction in the number of MYO10 foci. These results suggest that granulosa cells possess an ability to elaborate filopodia, which when directed towards the oocyte become actin-TZPs, and that MYO10 increases the efficiency of formation or maintenance of actin-TZPs.
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Affiliation(s)
- Sofia Granados-Aparici
- Department of Obstetrics and Gynecology, McGill University, Montreal, Canada.,Research Institute of the McGill University Health Center, Montreal, Canada
| | - Alexander Volodarsky-Perel
- Department of Obstetrics and Gynecology, McGill University, Montreal, Canada.,Research Institute of the McGill University Health Center, Montreal, Canada
| | - Qin Yang
- Research Institute of the McGill University Health Center, Montreal, Canada
| | - Sibat Anam
- Division of Experimental Medicine, McGill University, Montreal, Canada
| | - Togas Tulandi
- Department of Obstetrics and Gynecology, McGill University, Montreal, Canada.,Research Institute of the McGill University Health Center, Montreal, Canada
| | - William Buckett
- Department of Obstetrics and Gynecology, McGill University, Montreal, Canada.,Research Institute of the McGill University Health Center, Montreal, Canada
| | - Weon-Young Son
- Department of Obstetrics and Gynecology, McGill University, Montreal, Canada
| | - Grace Younes
- Department of Obstetrics and Gynecology, McGill University, Montreal, Canada.,Research Institute of the McGill University Health Center, Montreal, Canada
| | - Jin-Tae Chung
- Department of Obstetrics and Gynecology, McGill University, Montreal, Canada
| | - Shaoguang Jin
- Department of Obstetrics and Gynecology, McGill University, Montreal, Canada
| | | | - Hugh J Clarke
- Department of Obstetrics and Gynecology, McGill University, Montreal, Canada.,Research Institute of the McGill University Health Center, Montreal, Canada.,Division of Experimental Medicine, McGill University, Montreal, Canada
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8
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Abstract
Filopodia, microvilli and stereocilia represent an important group of plasma membrane protrusions. These specialized projections are supported by parallel bundles of actin filaments and have critical roles in sensing the external environment, increasing cell surface area, and acting as mechanosensors. While actin-associated proteins are essential for actin-filament elongation and bundling in these protrusions, myosin motors have a surprising role in the formation and extension of filopodia and stereocilia and in the organization of microvilli. Actin regulators and specific myosins collaborate in controlling the length of these structures. Myosins can transport cargoes along the length of these protrusions, and, in the case of stereocilia and microvilli, interactions with adaptors and cargoes can also serve to anchor adhesion receptors to the actin-rich core via functionally conserved motor-adaptor complexes. This review highlights recent progress in understanding the diverse roles myosins play in filopodia, microvilli and stereocilia.
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Affiliation(s)
- Anne Houdusse
- Structural Motility, Institut Curie, Paris Université Sciences et Lettres, Sorbonne Université, CNRS UMR144, 75005 Paris, France.
| | - Margaret A Titus
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA.
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9
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Chen YY, Syed AM, MacMillan P, Rocheleau JV, Chan WCW. Flow Rate Affects Nanoparticle Uptake into Endothelial Cells. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e1906274. [PMID: 32383233 DOI: 10.1002/adma.201906274] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 04/04/2020] [Accepted: 04/09/2020] [Indexed: 05/12/2023]
Abstract
Nanoparticles are commonly administered through systemic injection, which exposes them to the dynamic environment of the bloodstream. Injected nanoparticles travel within the blood and experience a wide range of flow velocities that induce varying shear rates to the blood vessels. Endothelial cells line these vessels, and have been shown to uptake nanoparticles during circulation, but it is difficult to characterize the flow-dependence of this interaction in vivo. Here, a microfluidic system is developed to control the flow rates of nanoparticles as they interact with endothelial cells. Gold nanoparticle uptake into endothelial cells is quantified at varying flow rates, and it is found that increased flow rates lead to decreased nanoparticle uptake. Endothelial cells respond to increased flow shear with decreased ability to uptake the nanoparticles. If cells are sheared the same way, nanoparticle uptake decreases as their flow velocity increases. Modifying nanoparticle surfaces with endothelial-cell-binding ligands partially restores uptake to nonflow levels, suggesting that functionalizing nanoparticles to bind to endothelial cells enables nanoparticles to resist flow effects. In the future, this microfluidic system can be used to test other nanoparticle-endothelial cell interactions under flow. The results of these studies can guide the engineering of nanoparticles for in vivo medical applications.
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Affiliation(s)
- Yih Yang Chen
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, M5S 3G9, Canada
- Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, M5S 3E1, Canada
| | - Abdullah Muhammad Syed
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, M5S 3G9, Canada
- Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, M5S 3E1, Canada
| | - Presley MacMillan
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, M5S 3G9, Canada
- Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, M5S 3E1, Canada
- Department of Chemistry, University of Toronto, Toronto, Ontario, M5S 3H6, Canada
| | - Jonathan V Rocheleau
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, M5S 3G9, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, M5S 1A8, Canada
- Toronto General Research Institute, University Health Network, Toronto, Ontario, M5G 2M9, Canada
| | - Warren C W Chan
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, M5S 3G9, Canada
- Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, M5S 3E1, Canada
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario, M5S 3E5, Canada
- Department of Material Science and Engineering, University of Toronto, Toronto, Ontario, M5S 1A1, Canada
- Department of Chemistry, University of Toronto, Toronto, Ontario, M5S 3H6, Canada
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10
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11
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Tunneling Nanotubes and the Eye: Intercellular Communication and Implications for Ocular Health and Disease. BIOMED RESEARCH INTERNATIONAL 2020; 2020:7246785. [PMID: 32352005 PMCID: PMC7171654 DOI: 10.1155/2020/7246785] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 03/10/2020] [Indexed: 12/31/2022]
Abstract
Cellular communication is an essential process for the development and maintenance of all tissues including the eye. Recently, a new method of cellular communication has been described, which relies on formation of tubules, called tunneling nanotubes (TNTs). These structures connect the cytoplasm of adjacent cells and allow the direct transport of cellular cargo between cells without the need for secretion into the extracellular milieu. TNTs may be an important mechanism for signaling between cells that reside long distances from each other or for cells in aqueous environments, where diffusion-based signaling is challenging. Given the wide range of cargoes transported, such as lysosomes, endosomes, mitochondria, viruses, and miRNAs, TNTs may play a role in normal homeostatic processes in the eye as well as function in ocular disease. This review will describe TNT cellular communication in ocular cell cultures and the mammalian eye in vivo, the role of TNTs in mitochondrial transport with an emphasis on mitochondrial eye diseases, and molecules involved in TNT biogenesis and their function in eyes, and finally, we will describe TNT formation in inflammation, cancer, and stem cells, focusing on pathological processes of particular interest to vision scientists.
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12
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Gudbergsson JM, Duroux M. Cripto-1 localizes to dynamic and shed filopodia associated with cellular migration in glioblastoma cells. Eur J Cell Biol 2019; 98:151044. [PMID: 31543278 DOI: 10.1016/j.ejcb.2019.151044] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 07/22/2019] [Accepted: 07/24/2019] [Indexed: 12/17/2022] Open
Abstract
Cripto-1 is a protein participating in tissue orientation during embryogenesis but has also been implicated in a wide variety of cancers, such as colon, lung and breast cancer. Cripto-1 plays a role in the regulation of different pathways, including TGF-β/Smad and Wnt/β-catenin, which are highly associated with cell migration both during embryonal development and cancer progression. Little is known about the detailed subcellular localization of cripto-1 and how it participates in the directional movement of cells. In this study, the subcellular localization of cripto-1 in glioblastoma cells was investigated in vitro with high-resolution microscopy techniques. Cripto-1 was found to be localized to dynamic and shed filopodia and transported between cells through tunneling nanotubes. Our results connect the refined subcellular localization of cripto-1 to its functions in cellular orientation and migration.
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Affiliation(s)
- Johann Mar Gudbergsson
- Laboratory of Immunology and Cancer Biology, Department of Health Science and Technology, Faculty of Medicine, Aalborg University, Fredrik Bajers Vej 3B, 9220 Aalborg Ø, Denmark.
| | - Meg Duroux
- Laboratory of Immunology and Cancer Biology, Department of Health Science and Technology, Faculty of Medicine, Aalborg University, Fredrik Bajers Vej 3B, 9220 Aalborg Ø, Denmark.
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13
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Boardman R, Pang V, Malhi N, Lynch AP, Leach L, Benest AV, Bates DO, Machado MJC. Activation of Notch signaling by soluble Dll4 decreases vascular permeability via a cAMP/PKA-dependent pathway. Am J Physiol Heart Circ Physiol 2019; 316:H1065-H1075. [PMID: 30681366 DOI: 10.1152/ajpheart.00610.2018] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The Notch ligand delta-like ligand 4 (Dll4), upregulated by VEGF, is a key regulator of vessel morphogenesis and function, controlling tip and stalk cell selection during sprouting angiogenesis. Inhibition of Dll4 results in hypersprouting, nonfunctional, poorly perfused vessels, suggesting a role for Dll4 in the formation of mature, reactive, functional vessels, with low permeability and able to restrict fluid and solute exchange. We tested the hypothesis that Dll4 controls transvascular fluid exchange. A recombinant protein expressing only the extracellular portion of Dll4 [soluble Dll4 (sDll4)] induced Notch signaling in endothelial cells (ECs), resulting in increased expression of vascular-endothelial cadherin, but not the tight junctional protein zonula occludens 1, at intercellular junctions. sDll4 decreased the permeability of FITC-labeled albumin across EC monolayers, and this effect was abrogated by coculture with the γ-secretase inhibitor N-[N-(3,5-difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butyl ester. One of the known molecular effectors responsible for strengthening EC-EC contacts is PKA, so we tested the effect of modulation of PKA on the sDll4-mediated reduction of permeability. Inhibition of PKA reversed the sDll4-mediated reduction in permeability and reduced expression of the Notch target gene Hey1. Knockdown of PKA reduced sDLL4-mediated vascular-endothelial cadherin junctional expression. sDll4 also caused a significant decrease in the hydraulic conductivity of rat mesenteric microvessels in vivo. This reduction was abolished upon coperfusion with the PKA inhibitor H89 dihydrochloride. These results indicate that Dll4 signaling through Notch activation acts through a cAMP/PKA pathway upon intercellular adherens junctions, but not tight junctions, to regulate endothelial barrier function. NEW & NOTEWORTHY Notch signaling reduces vascular permeability through stimulation of cAMP-dependent protein kinase A.
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Affiliation(s)
- Rachel Boardman
- Cancer Biology, Division of Cancer and Stem Cells, School of Medicine, Queen's Medical Centre, University of Nottingham , Nottingham , United Kingdom
| | - Vincent Pang
- Cancer Biology, Division of Cancer and Stem Cells, School of Medicine, Queen's Medical Centre, University of Nottingham , Nottingham , United Kingdom
| | - Naseeb Malhi
- Cancer Biology, Division of Cancer and Stem Cells, School of Medicine, Queen's Medical Centre, University of Nottingham , Nottingham , United Kingdom
| | - Amy P Lynch
- Cancer Biology, Division of Cancer and Stem Cells, School of Medicine, Queen's Medical Centre, University of Nottingham , Nottingham , United Kingdom
| | - Lopa Leach
- Division of Physiology Pharmacology and Neuroscience, School of Life Sciences, The Medical School , Nottingham , United Kingdom
| | - Andrew V Benest
- Cancer Biology, Division of Cancer and Stem Cells, School of Medicine, Queen's Medical Centre, University of Nottingham , Nottingham , United Kingdom.,The Centre of Membrane Proteins and Receptors, University of Birmingham and University of Nottingham, Midlands, United Kingdom
| | - David O Bates
- Cancer Biology, Division of Cancer and Stem Cells, School of Medicine, Queen's Medical Centre, University of Nottingham , Nottingham , United Kingdom.,The Centre of Membrane Proteins and Receptors, University of Birmingham and University of Nottingham, Midlands, United Kingdom
| | - Maria J C Machado
- Cancer Biology, Division of Cancer and Stem Cells, School of Medicine, Queen's Medical Centre, University of Nottingham , Nottingham , United Kingdom
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14
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Bachg AC, Horsthemke M, Skryabin BV, Klasen T, Nagelmann N, Faber C, Woodham E, Machesky LM, Bachg S, Stange R, Jeong HW, Adams RH, Bähler M, Hanley PJ. Phenotypic analysis of Myo10 knockout (Myo10 tm2/tm2) mice lacking full-length (motorized) but not brain-specific headless myosin X. Sci Rep 2019; 9:597. [PMID: 30679680 PMCID: PMC6345916 DOI: 10.1038/s41598-018-37160-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 12/04/2018] [Indexed: 01/04/2023] Open
Abstract
We investigated the physiological functions of Myo10 (myosin X) using Myo10 reporter knockout (Myo10tm2) mice. Full-length (motorized) Myo10 protein was deleted, but the brain-specific headless (Hdl) isoform (Hdl-Myo10) was still expressed in homozygous mutants. In vitro, we confirmed that Hdl-Myo10 does not induce filopodia, but it strongly localized to the plasma membrane independent of the MyTH4-FERM domain. Filopodia-inducing Myo10 is implicated in axon guidance and mice lacking the Myo10 cargo protein DCC (deleted in colorectal cancer) have severe commissural defects, whereas MRI (magnetic resonance imaging) of isolated brains revealed intact commissures in Myo10tm2/tm2 mice. However, reminiscent of Waardenburg syndrome, a neural crest disorder, Myo10tm2/tm2 mice exhibited pigmentation defects (white belly spots) and simple syndactyly with high penetrance (>95%), and 24% of mutant embryos developed exencephalus, a neural tube closure defect. Furthermore, Myo10tm2/tm2 mice consistently displayed bilateral persistence of the hyaloid vasculature, revealed by MRI and retinal whole-mount preparations. In principle, impaired tissue clearance could contribute to persistence of hyaloid vasculature and syndactyly. However, Myo10-deficient macrophages exhibited no defects in the phagocytosis of apoptotic or IgG-opsonized cells. RNA sequence analysis showed that Myo10 was the most strongly expressed unconventional myosin in retinal vascular endothelial cells and expression levels increased 4-fold between P6 and P15, when vertical sprouting angiogenesis gives rise to deeper layers. Nevertheless, imaging of isolated adult mutant retinas did not reveal vascularization defects. In summary, Myo10 is important for both prenatal (neural tube closure and digit formation) and postnatal development (hyaloid regression, but not retinal vascularization).
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Affiliation(s)
- Anne C Bachg
- Institut für Molekulare Zellbiologie, Westfälische Wilhelms-Universität Münster, 48149, Münster, Germany
| | - Markus Horsthemke
- Institut für Molekulare Zellbiologie, Westfälische Wilhelms-Universität Münster, 48149, Münster, Germany
| | - Boris V Skryabin
- Department of Medicine, Transgenic Animal and Genetic Engineering Models (TRAM), Westfälische Wilhelms-Universität Münster, 48149, Münster, Germany
| | - Tim Klasen
- Department of Clinical Radiology, Westfälische Wilhelms-Universität Münster, 48149, Münster, Germany
| | - Nina Nagelmann
- Department of Clinical Radiology, Westfälische Wilhelms-Universität Münster, 48149, Münster, Germany
| | - Cornelius Faber
- Department of Clinical Radiology, Westfälische Wilhelms-Universität Münster, 48149, Münster, Germany
| | - Emma Woodham
- Cancer Research UK Beatson Institute, Glasgow University College of Medical, Veterinary and Life Sciences Garscube Estate, Glasgow, G61 1BD, United Kingdom
| | - Laura M Machesky
- Cancer Research UK Beatson Institute, Glasgow University College of Medical, Veterinary and Life Sciences Garscube Estate, Glasgow, G61 1BD, United Kingdom
| | - Sandra Bachg
- Department of Regenerative Musculoskeletal Medicine, Institute of Musculoskeletal Medicine (IMM), University Hospital Münster, 48149, Münster, Germany
| | - Richard Stange
- Department of Regenerative Musculoskeletal Medicine, Institute of Musculoskeletal Medicine (IMM), University Hospital Münster, 48149, Münster, Germany
| | - Hyun-Woo Jeong
- Max Planck Institute for Molecular Biomedicine, Department of Tissue Morphogenesis, and University of Münster, Faculty of Medicine, 48149, Münster, Germany
| | - Ralf H Adams
- Max Planck Institute for Molecular Biomedicine, Department of Tissue Morphogenesis, and University of Münster, Faculty of Medicine, 48149, Münster, Germany
| | - Martin Bähler
- Institut für Molekulare Zellbiologie, Westfälische Wilhelms-Universität Münster, 48149, Münster, Germany
| | - Peter J Hanley
- Institut für Molekulare Zellbiologie, Westfälische Wilhelms-Universität Münster, 48149, Münster, Germany.
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15
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Fischer RS, Lam PY, Huttenlocher A, Waterman CM. Filopodia and focal adhesions: An integrated system driving branching morphogenesis in neuronal pathfinding and angiogenesis. Dev Biol 2018; 451:86-95. [PMID: 30193787 DOI: 10.1016/j.ydbio.2018.08.015] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 08/08/2018] [Accepted: 08/29/2018] [Indexed: 12/31/2022]
Abstract
Single cell branching during development in vertebrates is typified by neuronal branching to form neurites and vascular branches formed by sprouting angiogenesis. Neurons and endothelial tip cells possess subcellular protrusions that share many common features from the morphological to the molecular level. Both systems utilize filopodia as their cellular protrusion organelles and depend on specific integrin-mediated adhesions to the local extracellular matrix for guidance in their pathfinding. We discuss the similar molecular machineries involved in these two types of cell branch formation and use their analogy to propose a new mechanism for angiogenic filopodia function, namely as adhesion assembly sites. In support of this model we provide primary data of angiogenesis in zebrafish in vivo showing that the actin assembly factor VASP participates in both filopodia formation and adhesion assembly at the base of the filopodia, enabling forward progress of the tip cell. The use of filopodia and their associated adhesions provide a common mechanism for neuronal and endothelial pathfinding during development in response to extracellular matrix cues.
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Affiliation(s)
- Robert S Fischer
- Cell and Developmental Biology Center, National Heart Lung and Blood Institute, National Institutes of Health, United States
| | - Pui-Ying Lam
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Utah, United States
| | - Anna Huttenlocher
- Departments of Pediatrics and Medical Microbiology and Immunology, School of Medicine and Public Health, University of Wisconsin, United States
| | - Clare M Waterman
- Cell and Developmental Biology Center, National Heart Lung and Blood Institute, National Institutes of Health, United States.
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16
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Tokuo H, Bhawan J, Coluccio LM. Myosin X is required for efficient melanoblast migration and melanoma initiation and metastasis. Sci Rep 2018; 8:10449. [PMID: 29993000 PMCID: PMC6041326 DOI: 10.1038/s41598-018-28717-y] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 06/15/2018] [Indexed: 12/20/2022] Open
Abstract
Myosin X (Myo10), an actin-associated molecular motor, has a clear role in filopodia induction and cell migration in vitro, but its role in vivo in mammals is not well understood. Here, we investigate the role of Myo10 in melanocyte lineage and melanoma induction. We found that Myo10 knockout (Myo10KO) mice exhibit a white spot on their belly caused by reduced melanoblast migration. Myo10KO mice crossed with available mice that conditionally express in melanocytes the BRAFV600E mutation combined with Pten silencing exhibited reduced melanoma development and metastasis, which extended medial survival time. Knockdown of Myo10 (Myo10kd) in B16F1 mouse melanoma cell lines decreased lung colonization after tail-vein injection. Myo10kd also inhibited long protrusion (LP) formation by reducing the transportation of its cargo molecule vasodilator-stimulated phosphoprotein (VASP) to the leading edge of migrating cells. These findings provide the first genetic evidence for the involvement of Myo10 not only in melanoblast migration, but also in melanoma development and metastasis.
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Affiliation(s)
- Hiroshi Tokuo
- Department of Physiology & Biophysics, Boston University School of Medicine, Boston, MA, 02118, USA.
| | - Jag Bhawan
- Department of Dermatology, Boston University School of Medicine, Boston, MA, 02118, USA
| | - Lynne M Coluccio
- Department of Physiology & Biophysics, Boston University School of Medicine, Boston, MA, 02118, USA
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17
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18
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Angiogenic Factors produced by Hypoxic Cells are a leading driver of Anastomoses in Sprouting Angiogenesis-a computational study. Sci Rep 2018; 8:8726. [PMID: 29880828 PMCID: PMC5992150 DOI: 10.1038/s41598-018-27034-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 05/29/2018] [Indexed: 12/21/2022] Open
Abstract
Angiogenesis - the growth of new blood vessels from a pre-existing vasculature - is key in both physiological processes and on several pathological scenarios such as cancer progression or diabetic retinopathy. For the new vascular networks to be functional, it is required that the growing sprouts merge either with an existing functional mature vessel or with another growing sprout. This process is called anastomosis. We present a systematic 2D and 3D computational study of vessel growth in a tissue to address the capability of angiogenic factor gradients to drive anastomosis formation. We consider that these growth factors are produced only by tissue cells in hypoxia, i.e. until nearby vessels merge and become capable of carrying blood and irrigating their vicinity. We demonstrate that this increased production of angiogenic factors by hypoxic cells is able to promote vessel anastomoses events in both 2D and 3D. The simulations also verify that the morphology of these networks has an increased resilience toward variations in the endothelial cell's proliferation and chemotactic response. The distribution of tissue cells and the concentration of the growth factors they produce are the major factors in determining the final morphology of the network.
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19
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Liakath-Ali K, Vancollie VE, Sequeira I, Lelliott CJ, Watt FM. Myosin 10 is involved in murine pigmentation. Exp Dermatol 2018; 28:391-394. [PMID: 29509981 PMCID: PMC6519374 DOI: 10.1111/exd.13528] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/27/2018] [Indexed: 12/25/2022]
Abstract
Myosins are molecular motors that are well known for their role in cell movement and contractile functions. Although extensively studied in muscle physiology, little is known about the function of myosins in mammalian skin. As part of the Sanger Institute Mouse Genetics Project, we have identified a role for Myo10 in pigmentation, with a phenotype unlike those of Myo5a or Myo7a. Adult mice homozygous for a disrupted Myo10 allele on a C57BL/6N background displayed a high degree of penetrance for white patches on their abdomen and dorsal surface. Forepaw syndactyly and hind paw syndactyly were also observed in these mice. Tail epidermal wholemounts showed a complete lack of melanocytes in the hair follicles and interfollicular epidermis. Myo10 has previously been implicated in human pigmentation. Our current study reveals involvement of Myo10 in murine skin pigmentation.
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Affiliation(s)
| | | | - Inês Sequeira
- Centre for Stem Cells & Regenerative Medicine, King's College London, London, UK
| | | | - Fiona M Watt
- Centre for Stem Cells & Regenerative Medicine, King's College London, London, UK
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20
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Heimsath EG, Yim YI, Mustapha M, Hammer JA, Cheney RE. Myosin-X knockout is semi-lethal and demonstrates that myosin-X functions in neural tube closure, pigmentation, hyaloid vasculature regression, and filopodia formation. Sci Rep 2017; 7:17354. [PMID: 29229982 PMCID: PMC5725431 DOI: 10.1038/s41598-017-17638-x] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Accepted: 11/28/2017] [Indexed: 01/07/2023] Open
Abstract
Myosin-X (Myo10) is an unconventional myosin best known for its striking localization to the tips of filopodia. Despite the broad expression of Myo10 in vertebrate tissues, its functions at the organismal level remain largely unknown. We report here the generation of KO-first (Myo10tm1a/tm1a), floxed (Myo10tm1c/tm1c), and KO mice (Myo10tm1d/tm1d). Complete knockout of Myo10 is semi-lethal, with over half of homozygous KO embryos exhibiting exencephaly, a severe defect in neural tube closure. All Myo10 KO mice that survive birth exhibit a white belly spot, all have persistent fetal vasculature in the eye, and ~50% have webbed digits. Myo10 KO mice that survive birth can breed and produce litters of KO embryos, demonstrating that Myo10 is not absolutely essential for mitosis, meiosis, adult survival, or fertility. KO-first mice and an independent spontaneous deletion (Myo10m1J/m1J) exhibit the same core phenotypes. During retinal angiogenesis, KO mice exhibit a ~50% decrease in endothelial filopodia, demonstrating that Myo10 is required to form normal numbers of filopodia in vivo. The Myo10 mice generated here demonstrate that Myo10 has important functions in mammalian development and provide key tools for defining the functions of Myo10 in vivo.
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Affiliation(s)
- Ernest G Heimsath
- Department of Cell Biology and Physiology and Lineberger Comprehensive Cancer Center, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Yang-In Yim
- Cell Biology and Physiology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Mirna Mustapha
- Department of Otolaryngology, Stanford University School of Medicine, Palo Alto, CA, 94305, USA
| | - John A Hammer
- Cell Biology and Physiology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Richard E Cheney
- Department of Cell Biology and Physiology and Lineberger Comprehensive Cancer Center, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA. .,Cell Biology and Physiology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA.
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21
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ROS induced distribution of mitochondria to filopodia by Myo19 depends on a class specific tryptophan in the motor domain. Sci Rep 2017; 7:11577. [PMID: 28912530 PMCID: PMC5599611 DOI: 10.1038/s41598-017-11002-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Accepted: 08/17/2017] [Indexed: 01/08/2023] Open
Abstract
The role of the actin cytoskeleton in relation to mitochondria function and dynamics is only recently beginning to be recognized. Myo19 is an actin-based motor that is bound to the outer mitochondrial membrane and promotes the localization of mitochondria to filopodia in response to glucose starvation. However, how glucose starvation induces mitochondria localization to filopodia, what are the dynamics of this process and which enzymatic adaptation allows the translocation of mitochondria to filopodia are not known. Here we show that reactive oxygen species (ROS) mimic and mediate the glucose starvation induced phenotype. In addition, time-lapse fluorescent microscopy reveals that ROS-induced Myo19 motility is a highly dynamic process which is coupled to filopodia elongation and retraction. Interestingly, Myo19 motility is inhibited by back-to-consensus-mutation of a unique residue of class XIX myosins in the motor domain. Kinetic analysis of the purified mutant Myo19 motor domain reveals that the duty ratio (time spent strongly bound to actin) is highly compromised in comparison to that of the WT motor domain, indicating that Myo19 unique motor properties are necessary to propel mitochondria to filopodia tips. In summary, our study demonstrates the contribution of actin-based motility to the mitochondrial localization to filopodia by specific cellular cues.
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22
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Ronca R, Benkheil M, Mitola S, Struyf S, Liekens S. Tumor angiogenesis revisited: Regulators and clinical implications. Med Res Rev 2017. [PMID: 28643862 DOI: 10.1002/med.21452] [Citation(s) in RCA: 124] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Since Judah Folkman hypothesized in 1971 that angiogenesis is required for solid tumor growth, numerous studies have been conducted to unravel the angiogenesis process, analyze its role in primary tumor growth, metastasis and angiogenic diseases, and to develop inhibitors of proangiogenic factors. These studies have led in 2004 to the approval of the first antiangiogenic agent (bevacizumab, a humanized antibody targeting vascular endothelial growth factor) for the treatment of patients with metastatic colorectal cancer. This approval launched great expectations for the use of antiangiogenic therapy for malignant diseases. However, these expectations have not been met and, as knowledge of blood vessel formation accumulates, many of the original paradigms no longer hold. Therefore, the regulators and clinical implications of angiogenesis need to be revisited. In this review, we discuss recently identified angiogenesis mediators and pathways, new concepts that have emerged over the past 10 years, tumor resistance and toxicity associated with the use of currently available antiangiogenic treatment and potentially new targets and/or approaches for malignant and nonmalignant neovascular diseases.
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Affiliation(s)
- Roberto Ronca
- Experimental Oncology and Immunology, Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Mohammed Benkheil
- Laboratory of Virology and Chemotherapy, Rega Institute for Medical Research, Leuven, Belgium
| | - Stefania Mitola
- Experimental Oncology and Immunology, Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Sofie Struyf
- Laboratory of Molecular Immunology, Rega Institute for Medical Research, Leuven, Belgium
| | - Sandra Liekens
- Laboratory of Virology and Chemotherapy, Rega Institute for Medical Research, Leuven, Belgium
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23
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Cavalheiro RP, Lima MA, Jarrouge-Bouças TR, Viana GM, Lopes CC, Coulson-Thomas VJ, Dreyfuss JL, Yates EA, Tersariol ILS, Nader HB. Coupling of vinculin to F-actin demands Syndecan-4 proteoglycan. Matrix Biol 2017; 63:23-37. [PMID: 28062282 DOI: 10.1016/j.matbio.2016.12.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 11/04/2016] [Accepted: 12/04/2016] [Indexed: 01/18/2023]
Abstract
Syndecans are heparan sulfate proteoglycans characterized as transmembrane receptors that act cooperatively with the cell surface and extracellular matrix proteins. Syn4 knockdown was performed in order to address its role in endothelial cells (EC) behavior. Normal EC and shRNA-Syn4-EC cells were studied comparatively using complementary confocal, super-resolution and non-linear microscopic techniques. Confocal and super-resolution microscopy revealed that Syn4 knockdown alters the level and arrangement of essential proteins for focal adhesion, evidenced by the decoupling of vinculin from F-actin filaments. Furthermore, Syn4 knockdown alters the actin network leading to filopodial protrusions connected by VE-cadherin-rich junction. shRNA-Syn4-EC showed reduced adhesion and increased migration. Also, Syn4 silencing alters cell cycle as well as cell proliferation. Moreover, the ability of EC to form tube-like structures in matrigel is reduced when Syn4 is silenced. Together, the results suggest a mechanism in which Syndecan-4 acts as a central mediator that bridges fibronectin, integrin and intracellular components (actin and vinculin) and once silenced, the cytoskeleton protein network is disrupted. Ultimately, the results highlight Syn4 relevance for balanced cell behavior.
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Affiliation(s)
- R P Cavalheiro
- Disciplina de Biologia Molecular, Departamento de Bioquímica, Escola Paulista de Medicina, Universidade Federal de São Paulo, SP, Brazil
| | - M A Lima
- Disciplina de Biologia Molecular, Departamento de Bioquímica, Escola Paulista de Medicina, Universidade Federal de São Paulo, SP, Brazil; Institute of Integrative Biology, Department of Biochemistry, University of Liverpool, Liverpool, UK
| | - T R Jarrouge-Bouças
- Disciplina de Biologia Molecular, Departamento de Bioquímica, Escola Paulista de Medicina, Universidade Federal de São Paulo, SP, Brazil
| | - G M Viana
- Disciplina de Biologia Molecular, Departamento de Bioquímica, Escola Paulista de Medicina, Universidade Federal de São Paulo, SP, Brazil
| | - C C Lopes
- Disciplina de Biologia Molecular, Departamento de Bioquímica, Escola Paulista de Medicina, Universidade Federal de São Paulo, SP, Brazil; Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Universidade Federal de São Paulo, Diadema, SP, Brazil
| | - V J Coulson-Thomas
- Disciplina de Biologia Molecular, Departamento de Bioquímica, Escola Paulista de Medicina, Universidade Federal de São Paulo, SP, Brazil; University of Houston, College of Optometry, The Ocular Surface Institute (TOSI), Houston, USA
| | - J L Dreyfuss
- Disciplina de Biologia Molecular, Departamento de Bioquímica, Escola Paulista de Medicina, Universidade Federal de São Paulo, SP, Brazil; Grupo Interdisciplinar de Ciências Exatas em Saúde, Universidade Federal de São Paulo, SP, Brazil
| | - E A Yates
- Disciplina de Biologia Molecular, Departamento de Bioquímica, Escola Paulista de Medicina, Universidade Federal de São Paulo, SP, Brazil; Institute of Integrative Biology, Department of Biochemistry, University of Liverpool, Liverpool, UK
| | - I L S Tersariol
- Disciplina de Biologia Molecular, Departamento de Bioquímica, Escola Paulista de Medicina, Universidade Federal de São Paulo, SP, Brazil
| | - H B Nader
- Disciplina de Biologia Molecular, Departamento de Bioquímica, Escola Paulista de Medicina, Universidade Federal de São Paulo, SP, Brazil.
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Zulueta-Coarasa T, Fernandez-Gonzalez R. Tension (re)builds: Biophysical mechanisms of embryonic wound repair. Mech Dev 2016; 144:43-52. [PMID: 27989746 DOI: 10.1016/j.mod.2016.11.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 11/15/2016] [Accepted: 11/18/2016] [Indexed: 12/24/2022]
Abstract
Embryonic tissues display an outstanding ability to rapidly repair wounds. Epithelia, in particular, serve as protective layers that line internal organs and form the skin. Thus, maintenance of epithelial integrity is of utmost importance for animal survival, particularly at embryonic stages, when an immune system has not yet fully developed. Rapid embryonic repair of epithelial tissues is conserved across species, and involves the collective migration of the cells around the wound. The migratory cell behaviours associated with wound repair require the generation and transmission of mechanical forces, not only for the cells to move, but also to coordinate their movements. Here, we review the forces involved in embryonic wound repair. We discuss how different force-generating structures are assembled at the molecular level, and the mechanisms that maintain the balance between force-generating structures as wounds close. Finally, we describe the mechanisms that cells use to coordinate the generation of mechanical forces around the wound. Collective cell movements and their misregulation have been associated with defective tissue repair, developmental abnormalities and cancer metastasis. Thus, we propose that understanding the role of mechanical forces during embryonic wound closure will be crucial to develop therapeutic interventions that promote or prevent collective cell movements under pathological conditions.
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Affiliation(s)
- Teresa Zulueta-Coarasa
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada; Ted Rogers Centre for Heart Research, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Rodrigo Fernandez-Gonzalez
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada; Ted Rogers Centre for Heart Research, University of Toronto, Toronto, ON M5G 1M1, Canada; Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada; Developmental and Stem Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada.
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25
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Weck ML, Grega-Larson NE, Tyska MJ. MyTH4-FERM myosins in the assembly and maintenance of actin-based protrusions. Curr Opin Cell Biol 2016; 44:68-78. [PMID: 27836411 DOI: 10.1016/j.ceb.2016.10.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 10/12/2016] [Indexed: 12/13/2022]
Abstract
Unconventional myosins are actin-based molecular motors that serve a multitude of roles within the cell. One group of myosin motors, the MyTH4-FERM myosins, play an integral part in building and maintaining finger-like protrusions, which allow cells to interact with their external environment. Suggested to act primarily as transporters, these motor proteins enrich adhesion molecules, actin-regulatory proteins and other factors at the tips of filopodia, microvilli, and stereocilia. Below we review data from biophysical, biochemical, and cell biological studies, which implicate these myosins as central players in the assembly, maintenance and function of actin-based protrusions.
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Affiliation(s)
- Meredith L Weck
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, 3154 MRB III, PMB 407935, 465 21st Avenue South, Nashville, TN 37240-7935, United States
| | - Nathan E Grega-Larson
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, 3154 MRB III, PMB 407935, 465 21st Avenue South, Nashville, TN 37240-7935, United States
| | - Matthew J Tyska
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, 3154 MRB III, PMB 407935, 465 21st Avenue South, Nashville, TN 37240-7935, United States.
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26
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Weck ML, Crawley SW, Stone CR, Tyska MJ. Myosin-7b Promotes Distal Tip Localization of the Intermicrovillar Adhesion Complex. Curr Biol 2016; 26:2717-2728. [PMID: 27666969 DOI: 10.1016/j.cub.2016.08.014] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 07/01/2016] [Accepted: 08/03/2016] [Indexed: 12/11/2022]
Abstract
Transporting epithelial cells interact with the luminal environment using a tightly packed array of microvilli known as the brush border. During intestinal epithelial differentiation, microvillar packing and organization are driven by cadherin-dependent adhesion complexes that localize to the distal tips of microvilli, where they drive physical interactions between neighboring protrusions. Although enrichment of the "intermicrovillar adhesion complex" (IMAC) at distal tips is required for proper function, the mechanism driving tip accumulation of these factors remains unclear. Here, we report that the actin-based motor myosin-7b (Myo7b) promotes the accumulation of IMAC components at microvillar tips. Myo7b is highly enriched at the tips of microvilli in both kidney and intestinal brush borders, and loss of Myo7b in differentiating intestinal epithelial cells disrupts intermicrovillar adhesion and, thus, brush border assembly. Analysis of cells lacking Myo7b revealed that IMAC components and the resulting intermicrovillar adhesion links are mislocalized along the microvillar axis rather than enriched at the distal tips. We also found that Myo7b motor domains are capable of supporting tip-directed transport. However, motor activity is supplemented by other passive targeting mechanisms that together drive highly efficient IMAC accumulation at the tips. These findings illuminate the molecular basis of IMAC enrichment at microvillar tips and hold important implications for understanding apical morphogenesis in transporting and sensory epithelial tissues.
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Affiliation(s)
- Meredith L Weck
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37240, USA
| | - Scott W Crawley
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37240, USA
| | - Colin R Stone
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37240, USA
| | - Matthew J Tyska
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37240, USA.
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27
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Tyska MJ. Listen to your gut: Using adhesion to shape the surface of functionally diverse epithelia. Rare Dis 2016. [DOI: 10.1080/21675511.2016.1220469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Affiliation(s)
- Matthew J. Tyska
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, USA
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28
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Lai M, Guo Y, Ma J, Yu H, Zhao D, Fan W, Ju X, Sheikh MA, Malik YS, Xiong W, Guo W, Zhu X. Myosin X regulates neuronal radial migration through interacting with N-cadherin. Front Cell Neurosci 2015; 9:326. [PMID: 26347613 PMCID: PMC4539528 DOI: 10.3389/fncel.2015.00326] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 08/06/2015] [Indexed: 11/23/2022] Open
Abstract
Proper brain function depends on correct neuronal migration during development, which is known to be regulated by cytoskeletal dynamics and cell-cell adhesion. Myosin X (Myo10), an uncharacteristic member of the myosin family, is an important regulator of cytoskeleton that modulates cell motilities in many different cellular contexts. We previously reported that Myo10 was required for neuronal migration in the developing cerebral cortex, but the underlying mechanism was still largely unknown. Here, we found that knockdown of Myo10 expression disturbed the adherence of migrating neurons to radial glial fibers through abolishing surface Neuronal cadherin (N-cadherin) expression, thereby impaired neuronal migration in the developmental cortex. Next, we found Myo10 interacted with N-cadherin cellular domain through its FERM domain. Furthermore, we found knockdown of Myo10 disrupted N-cadherin subcellular distribution and led to localization of N-cadherin into Golgi apparatus and endosomal sorting vesicle. Taking together, these results reveal a novel mechanism of Myo10 interacting with N-cadherin and regulating its cell-surface expression, which is required for neuronal adhesion and migration.
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Affiliation(s)
- Mingming Lai
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University Changchun, China ; Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Dali University Dali, China
| | - Ye Guo
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University Changchun, China
| | - Jun Ma
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University Changchun, China
| | - Huali Yu
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University Changchun, China
| | - Dongdong Zhao
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University Changchun, China
| | - Wenqiang Fan
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University Changchun, China
| | - Xingda Ju
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University Changchun, China
| | - Muhammad A Sheikh
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University Changchun, China
| | - Yousra S Malik
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University Changchun, China
| | - Wencheng Xiong
- Department of Neurology, Georgia Regents University, Augusta GA, USA
| | - Weixiang Guo
- State Key Laboratory for Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences Beijing, China
| | - Xiaojuan Zhu
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University Changchun, China ; State Key Laboratory for Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences Beijing, China
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29
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Abraham S, Scarcia M, Bagshaw RD, McMahon K, Grant G, Harvey T, Yeo M, Esteves FO, Thygesen HH, Jones PF, Speirs V, Hanby AM, Selby PJ, Lorger M, Dear TN, Pawson T, Marshall CJ, Mavria G. A Rac/Cdc42 exchange factor complex promotes formation of lateral filopodia and blood vessel lumen morphogenesis. Nat Commun 2015; 6:7286. [PMID: 26129894 PMCID: PMC4507007 DOI: 10.1038/ncomms8286] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 04/26/2015] [Indexed: 12/18/2022] Open
Abstract
During angiogenesis, Rho-GTPases influence endothelial cell migration and cell-cell adhesion; however it is not known whether they control formation of vessel lumens, which are essential for blood flow. Here, using an organotypic system that recapitulates distinct stages of VEGF-dependent angiogenesis, we show that lumen formation requires early cytoskeletal remodelling and lateral cell-cell contacts, mediated through the RAC1 guanine nucleotide exchange factor (GEF) DOCK4 (dedicator of cytokinesis 4). DOCK4 signalling is necessary for lateral filopodial protrusions and tubule remodelling prior to lumen formation, whereas proximal, tip filopodia persist in the absence of DOCK4. VEGF-dependent Rac activation via DOCK4 is necessary for CDC42 activation to signal filopodia formation and depends on the activation of RHOG through the RHOG GEF, SGEF. VEGF promotes interaction of DOCK4 with the CDC42 GEF DOCK9. These studies identify a novel Rho-family GTPase activation cascade for the formation of endothelial cell filopodial protrusions necessary for tubule remodelling, thereby influencing subsequent stages of lumen morphogenesis.
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Affiliation(s)
- Sabu Abraham
- Institute of Cancer Research, Division of Cancer Biology, 237 Fulham Road, London SW3 6JB, UK
| | - Margherita Scarcia
- Leeds Institute of Cancer and Pathology, University of Leeds, St James' University Hospital, Beckett Street, Leeds LS9 7TF, UK
| | - Richard D. Bagshaw
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, M5G 1X5 Ontario, Canada
| | - Kathryn McMahon
- Leeds Institute of Cancer and Pathology, University of Leeds, St James' University Hospital, Beckett Street, Leeds LS9 7TF, UK
| | - Gary Grant
- Leeds Institute of Cancer and Pathology, University of Leeds, St James' University Hospital, Beckett Street, Leeds LS9 7TF, UK
| | - Tracey Harvey
- Leeds Institute of Cancer and Pathology, University of Leeds, St James' University Hospital, Beckett Street, Leeds LS9 7TF, UK
| | - Maggie Yeo
- Institute of Cancer Research, Division of Cancer Biology, 237 Fulham Road, London SW3 6JB, UK
| | - Filomena O.G. Esteves
- Leeds Institute of Cancer and Pathology, University of Leeds, St James' University Hospital, Beckett Street, Leeds LS9 7TF, UK
| | - Helene H. Thygesen
- Leeds Institute of Cancer and Pathology, University of Leeds, St James' University Hospital, Beckett Street, Leeds LS9 7TF, UK
| | - Pamela F. Jones
- Leeds Institutes of Molecular Medicine, University of Leeds, St James' University Hospital, Beckett Street, Leeds LS9 7TF, UK
| | - Valerie Speirs
- Leeds Institute of Cancer and Pathology, University of Leeds, St James' University Hospital, Beckett Street, Leeds LS9 7TF, UK
| | - Andrew M. Hanby
- Leeds Institute of Cancer and Pathology, University of Leeds, St James' University Hospital, Beckett Street, Leeds LS9 7TF, UK
| | - Peter J. Selby
- Leeds Institute of Cancer and Pathology, University of Leeds, St James' University Hospital, Beckett Street, Leeds LS9 7TF, UK
| | - Mihaela Lorger
- Leeds Institute of Cancer and Pathology, University of Leeds, St James' University Hospital, Beckett Street, Leeds LS9 7TF, UK
| | - T. Neil Dear
- Leeds Institutes of Molecular Medicine, University of Leeds, St James' University Hospital, Beckett Street, Leeds LS9 7TF, UK
| | - Tony Pawson
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, M5G 1X5 Ontario, Canada
| | - Christopher J. Marshall
- Institute of Cancer Research, Division of Cancer Biology, 237 Fulham Road, London SW3 6JB, UK
| | - Georgia Mavria
- Leeds Institute of Cancer and Pathology, University of Leeds, St James' University Hospital, Beckett Street, Leeds LS9 7TF, UK
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30
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Baumüller S, Lehnen H, Schmitz J, Fimmers R, Müller AM. The impact of insulin treatment on the expression of vascular endothelial cadherin and Beta-catenin in human fetoplacental vessels. Pediatr Dev Pathol 2015; 18:17-23. [PMID: 25361430 DOI: 10.2350/13-11-1400-oa.1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Vascular endothelial cadherin and β-catenin play a key role in establishment and maintenance of the endothelial monolayer integrity, regulation of vascular barrier function, and initiation of angiogenesis. The cadherin-catenin complex has been shown to be reduced in type 1 diabetic placenta, but the exact relationship between histopathologic findings and clinical data is not known. Immunohistochemistry of placental tissue from type 1, type 2, and gestational diabetes showed that diabetes per se might be compatible with normal levels of vascular endothelial (VE)-cadherin and β-catenin in fetoplacental vessels as long as the patient has not been treated with insulin. Immunoreactivity of VE-cadherin did correlate poorly with maternal glycemic control, as was investigated in this study, by birth weight, body mass index, and hemoglobin A1c (HbA1c). There was no correlation found between the immunoreactivity of β-catenin and birth weight, body mass index, or HbA1c. However our data did show a strong correlation between immunoreactivity and whether or not the patient had been treated with insulin. Patients diagnosed with gestational diabetes who had not been treated with insulin had similar levels of VE-cadherin and β-catenin to the control group, thus indicating that diabetes per se must not necessarily lead to a reduction. Our study suggests that therapeutic intervention using insulin in pregnancies complicated by diabetes might have potentially harmful effects on placental morphology. Future studies should further investigate these findings.
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Affiliation(s)
- Samira Baumüller
- 1 Department of Pediatric Pathology, University-Clinic of Bonn, Bonn, Germany
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31
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Yu H, Lai M, Guo Y, Yuan L, Lan Y, Wang X, Zhu X. Myo10 is required for neurogenic cell adhesion and migration. In Vitro Cell Dev Biol Anim 2014; 51:400-7. [PMID: 25491426 DOI: 10.1007/s11626-014-9845-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 11/02/2014] [Indexed: 12/27/2022]
Abstract
Myosin X (Myo10), an untraditional member of myosin superfamily, is characterized as an actin-based molecular motor, which plays a critical role in diverse cellular motile events. Previous research by our group has found that Myo10 influenced neuronal radial migration in developing neocortex, but the underlying mechanism is still largely unknown. In this study, we found that knockdown of endogenous Myo10 in a normal gonadotropin-releasing hormone (GnRH) neuronal cell line transfected with the large T antigen (NLT) induced the impairment of cell motility and orientation. In the wound healing assay, with the Golgi complex staining to display cell polarity, Myo10 knockdown cells were randomly oriented compared to the control. Furthermore, suppressing the expression of Myo10 decreased the ability of cell-matrix adhesion. N-cadherin, a calcium-dependent classical cell adhesion molecule, rescued the migration deficiency caused by Myo10 knockdown in cell aggregates and collagen gel assay. These results suggest that Myo10 is required for neurogenic cell migration through N-cadherin mediated cell adhesion.
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Affiliation(s)
- Huali Yu
- Key laboratory of Molecular Epigenetics of Ministry of Education, Institute of Cytology and Genetics, Northeast Normal University, No. 5268, Renmin Street, Changchun, Jilin, 130024, People's Republic of China
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32
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Ouderkirk JL, Krendel M. Non-muscle myosins in tumor progression, cancer cell invasion, and metastasis. Cytoskeleton (Hoboken) 2014; 71:447-63. [PMID: 25087729 DOI: 10.1002/cm.21187] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Revised: 07/28/2014] [Accepted: 07/29/2014] [Indexed: 02/06/2023]
Abstract
The actin cytoskeleton, which regulates cell polarity, adhesion, and migration, can influence cancer progression, including initial acquisition of malignant properties by normal cells, invasion of adjacent tissues, and metastasis to distant sites. Actin-dependent molecular motors, myosins, play key roles in regulating tumor progression and metastasis. In this review, we examine how non-muscle myosins regulate neoplastic transformation and cancer cell migration and invasion. Members of the myosin superfamily can act as either enhancers or suppressors of tumor progression. This review summarizes the current state of knowledge on how mutations or epigenetic changes in myosin genes and changes in myosin expression may affect tumor progression and patient outcomes and discusses the proposed mechanisms linking myosin inactivation or upregulation to malignant phenotype, cancer cell migration, and metastasis.
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Affiliation(s)
- Jessica L Ouderkirk
- Department of Cell and Developmental Biology, SUNY Upstate Medical University, 750 E. Adams St., Syracuse, New York
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Elevated expression of myosin X in tumours contributes to breast cancer aggressiveness and metastasis. Br J Cancer 2014; 111:539-50. [PMID: 24921915 PMCID: PMC4119973 DOI: 10.1038/bjc.2014.298] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Revised: 05/01/2014] [Accepted: 05/09/2014] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Myosin X (MYO10) was recently reported to promote tumour invasion by transporting integrins to filopodial tips in breast cancer. However, the role of MYO10 in tumours remains poorly defined. Here, we report that MYO10 is required in invadopodia to mediate invasive growth and extracellular matrix degradation, which depends on the binding of MYO10's pleckstrin homology domain to PtdIns(3,4,5)P3. METHODS The expression of MYO10 and its associations with clinicopathological and biological factors were examined in breast cancer cells and breast cancer specimens (n=120). Cell migration and invasion were investigated after the silencing of MYO10. The ability of cells to form invadopodia was studied using a fluorescein isothiocyanate-conjugated gelatin degradation assay. A mouse model was established to study tumour invasive growth and metastasis in vivo. RESULTS Elevated MYO10 levels were correlated with oestrogen receptor status, progesterone receptor status, poor differentiation, and lymph node metastasis. Silencing MYO10 reduced cell migration and invasion. Invadopodia were responsible for MYO10's role in promoting invasion. Furthermore, decreased invasive growth and lung metastasis were observed in the MYO10-silenced nude mouse model. CONCLUSIONS Our findings suggest that elevated MYO10 expression increases the aggressiveness of breast cancer; this effect is dependent on the involvement of MYO10 in invadopodial formation.
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Ferreira Tojais N, Peghaire C, Franzl N, Larrieu-Lahargue F, Jaspard B, Reynaud A, Moreau C, Couffinhal T, Duplàa C, Dufourcq P. Frizzled7 controls vascular permeability through the Wnt-canonical pathway and cross-talk with endothelial cell junction complexes. Cardiovasc Res 2014; 103:291-303. [PMID: 24866384 DOI: 10.1093/cvr/cvu133] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
AIMS Vascular permeability is essential for the health of normal tissues and is an important characteristic of many disease states. The role of the Wnt/frizzled pathway in vascular biology has recently been reported. The objectives of this study are to analyse the role of Frizzled7 (Fzd7) receptor in the control of vascular integrity. METHODS AND RESULTS Fzd7 is expressed in endothelial cells and accumulates at the points of cell-cell contact in association with VE-cadherin and β-catenin, two major adherens junction molecules. To selectively delete fzd7 in the vasculature, we developed gene targeting approaches using CreLox strategy in mice. Genetic fzd7 inhibition in the endothelium increases vascular permeability in basal and factor-induced conditions. On the cellular level, fzd7 knockdown or depletion leads to an increase in paracellular permeability with a loss of adherens junction organization. These impairments are associated with a decrease in both VE-Cadherin and β-catenin expression, a decrease in their association and an increase of tyrosine phosphorylation of VE-cadherin/β-catenin. Fzd7 transduces a Wnt/β-catenin signalling cascade that is required to regulate β-catenin and canonical target gene expression. Finally, LiCl, a GSK3 inhibitor, and β-catenin overexpression rescued endothelial integrity and adherens junction organization, induced by fzd7 deletion. CONCLUSION These findings establish that Fzd7 is a new partner of adherens junctional complex and represents a novel molecular switch for the control of vascular permeability via activation of the Wnt-canonical pathway.
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Affiliation(s)
- Nancy Ferreira Tojais
- Adaptation cardiovasculaire à l'ischémie, INSERM U1034, 125 Avenue du Haut Lévèque, 33 600 Pessac, France Adaptation cardiovasculaire à l'ischémie, Bordeaux University, U1034, Pessac, France Stanford University School of Medicine, Stanford, CA, USA
| | - Claire Peghaire
- Adaptation cardiovasculaire à l'ischémie, INSERM U1034, 125 Avenue du Haut Lévèque, 33 600 Pessac, France Adaptation cardiovasculaire à l'ischémie, Bordeaux University, U1034, Pessac, France
| | - Nathalie Franzl
- Adaptation cardiovasculaire à l'ischémie, INSERM U1034, 125 Avenue du Haut Lévèque, 33 600 Pessac, France Adaptation cardiovasculaire à l'ischémie, Bordeaux University, U1034, Pessac, France
| | - Frédéric Larrieu-Lahargue
- Adaptation cardiovasculaire à l'ischémie, INSERM U1034, 125 Avenue du Haut Lévèque, 33 600 Pessac, France Adaptation cardiovasculaire à l'ischémie, Bordeaux University, U1034, Pessac, France
| | - Béatrice Jaspard
- Adaptation cardiovasculaire à l'ischémie, INSERM U1034, 125 Avenue du Haut Lévèque, 33 600 Pessac, France Adaptation cardiovasculaire à l'ischémie, Bordeaux University, U1034, Pessac, France
| | - Annabelle Reynaud
- Adaptation cardiovasculaire à l'ischémie, INSERM U1034, 125 Avenue du Haut Lévèque, 33 600 Pessac, France Adaptation cardiovasculaire à l'ischémie, Bordeaux University, U1034, Pessac, France
| | - Catherine Moreau
- Adaptation cardiovasculaire à l'ischémie, INSERM U1034, 125 Avenue du Haut Lévèque, 33 600 Pessac, France Adaptation cardiovasculaire à l'ischémie, Bordeaux University, U1034, Pessac, France
| | - Thierry Couffinhal
- Adaptation cardiovasculaire à l'ischémie, INSERM U1034, 125 Avenue du Haut Lévèque, 33 600 Pessac, France Adaptation cardiovasculaire à l'ischémie, Bordeaux University, U1034, Pessac, France Department of Cardiology, Pôle Cardiothoracique, Hôpital Haut Lévêque, Pessac, France
| | - Cécile Duplàa
- Adaptation cardiovasculaire à l'ischémie, INSERM U1034, 125 Avenue du Haut Lévèque, 33 600 Pessac, France Adaptation cardiovasculaire à l'ischémie, Bordeaux University, U1034, Pessac, France
| | - Pascale Dufourcq
- Adaptation cardiovasculaire à l'ischémie, INSERM U1034, 125 Avenue du Haut Lévèque, 33 600 Pessac, France Adaptation cardiovasculaire à l'ischémie, Bordeaux University, U1034, Pessac, France
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Neufeld S, Planas-Paz L, Lammert E. Blood and lymphatic vascular tube formation in mouse. Semin Cell Dev Biol 2014; 31:115-23. [PMID: 24631829 DOI: 10.1016/j.semcdb.2014.02.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Accepted: 02/26/2014] [Indexed: 12/30/2022]
Abstract
The blood and lymphatic vasculatures are essential for nutrient delivery, gas exchange and fluid homeostasis in all tissues of higher vertebrates. They are composed of a hierarchical network of vessels, which are lined by vascular or lymphatic endothelial cells. For blood vascular lumen formation to occur, endothelial cell cords polarize creating apposing apical cell surfaces, which repulse each other and give rise to a small intercellular lumen. Following cell shape changes, the vascular lumen expands. Various junctional proteins, polarity complexes, extracellular matrix binding and actin remodelling molecules are required for blood vascular lumen formation. In contrast, little is known regarding the molecular mechanisms leading to lymphatic vascular tube formation. Current models agree that lymphatic vessels share a blood vessel origin, but they differ in identifying the mechanism by which a lymphatic lumen is formed. A ballooning mechanism was proposed, in which lymph sacs are connected via their lumen to the cardinal veins. Alternatively, a mechanism involving budding of streams of lymphatic endothelial cells from either the cardinal veins or both the cardinal veins and the intersomitic vessels, and subsequent assembly and lumenisation was recently described. Here, we discuss what is currently known about the molecular and cellular machinery that guides blood and lymphatic vascular tube formation in mouse.
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Affiliation(s)
- Sofia Neufeld
- Institute of Metabolic Physiology, Heinrich-Heine Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
| | - Lara Planas-Paz
- Institute of Metabolic Physiology, Heinrich-Heine Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
| | - Eckhard Lammert
- Institute of Metabolic Physiology, Heinrich-Heine Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany; Institute for Beta Cell Biology, German Diabetes Center, Auf'm Hennekamp 65, 40225 Düsseldorf, Germany.
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36
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Lai M, Li L, Ju X, Yu H, Zhu X. Cloning, characterization, and promoter analysis of mouse Myo10 gene. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2013; 32:354-65. [PMID: 23742061 DOI: 10.1080/15257770.2013.790551] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Myosin X (Myo10) is an unconventional myosin associated with filopodia motility. Recent studies show that in addition to full-length Myo10, brain expresses a shorter form of Myo10 that lacks a myosin motor domain named headless Myo10. Herein, we analyzed and cloned 2-kb of the 5'-upstream sequences of mouse full-length Myo10 (fMyo10) and headless Myo10 (hMyo10) to understand the transcriptional regulation of the Myo10 gene. The putative transcription factor binding sites and CpG island were analyzed by a bioinformatic approach. Luciferase reporter assays showed that the 2-kb of 5'-upstream sequences of both fMyo10 and hMyo10 had promoter activities.
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Affiliation(s)
- Mingming Lai
- Key Laboratory of Molecular Epigenetics of Ministry of Education, Institute of Cytology and Genetics, Northeast Normal University, Changchun, China
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Lin WH, Hurley JT, Raines AN, Cheney RE, Webb DJ. Myosin X and its motorless isoform differentially modulate dendritic spine development by regulating trafficking and retention of vasodilator-stimulated phosphoprotein. J Cell Sci 2013; 126:4756-68. [PMID: 23943878 DOI: 10.1242/jcs.132969] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Myosin X (Myo10) is an unconventional myosin with two known isoforms: full-length (FL)-Myo10 that has motor activity, and a recently identified brain-expressed isoform, headless (Hdl)-Myo10, which lacks most of the motor domain. FL-Myo10 is involved in the regulation of filopodia formation in non-neuronal cells; however, the biological function of Hdl-Myo10 remains largely unknown. Here, we show that FL- and Hdl-Myo10 have important, but distinct, roles in the development of dendritic spines and synapses in hippocampal neurons. FL-Myo10 induces formation of dendritic filopodia and modulates filopodia dynamics by trafficking the actin-binding protein vasodilator-stimulated phosphoprotein (VASP) to the tips of filopodia. By contrast, Hdl-Myo10 acts on dendritic spines to enhance spine and synaptic density as well as spine head expansion by increasing the retention of VASP in spines. Thus, this study demonstrates a novel biological function for Hdl-Myo10 and an important new role for both Myo10 isoforms in the development of dendritic spines and synapses.
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Affiliation(s)
- Wan-Hsin Lin
- Department of Biological Sciences and Vanderbilt Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, Tennessee 37235, USA
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Gousset K, Marzo L, Commere PH, Zurzolo C. Myo10 is a key regulator of TNT formation in neuronal cells. J Cell Sci 2013; 126:4424-35. [PMID: 23886947 DOI: 10.1242/jcs.129239] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Cell-to-cell communication is essential in multicellular organisms. Tunneling nanotubes (TNTs) have emerged as a new type of intercellular spreading mechanism allowing the transport of various signals, organelles and pathogens. Here, we study the role of the unconventional molecular motor myosin-X (Myo10) in the formation of functional TNTs within neuronal CAD cells. Myo10 protein expression increases the number of TNTs and the transfer of vesicles between co-cultured cells. We also show that TNT formation requires both the motor and tail domains of the protein, and identify the F2 lobe of the FERM domain within the Myo10 tail as necessary for TNT formation. Taken together, these results indicate that, in neuronal cells, TNTs can arise from a subset of Myo10-driven dorsal filopodia, independent of its binding to integrins and N-cadherins. In addition our data highlight the existence of different mechanisms for the establishment and regulation of TNTs in neuronal cells and other cell types.
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Affiliation(s)
- Karine Gousset
- Institut Pasteur, 25 Rue du Dr Roux, Unité de Traffic Membranaire et Pathogenèse, 75724 Paris Cedex 15, France
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Heckman CA, Plummer HK. Filopodia as sensors. Cell Signal 2013; 25:2298-311. [PMID: 23876793 DOI: 10.1016/j.cellsig.2013.07.006] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Revised: 07/04/2013] [Accepted: 07/09/2013] [Indexed: 12/19/2022]
Abstract
Filopodia are sensors on both excitable and non-excitable cells. The sensing function is well documented in neurons and blood vessels of adult animals and is obvious during dorsal closure in embryonic development. Nerve cells extend neurites in a bidirectional fashion with growth cones at the tips where filopodia are concentrated. Their sensing of environmental cues underpins the axon's ability to "guide," bypassing non-target cells and moving toward the target to be innervated. This review focuses on the role of filopodia structure and dynamics in the detection of environmental cues, including both the extracellular matrix (ECM) and the surfaces of neighboring cells. Other protrusions including the stereocilia of the inner ear and epididymus, the invertebrate Type I mechanosensors, and the elongated processes connecting osteocytes, share certain principles of organization with the filopodia. Actin bundles, which may be inside or outside of the excitable cell, function to transduce stress from physical perturbations into ion signals. There are different ways of detecting such perturbations. Osteocyte processes contain an actin core and are physically anchored on an extracellular structure by integrins. Some Type I mechanosensors have bridge proteins that anchor microtubules to the membrane, but bundles of actin in accessory cells exert stress on this complex. Hair cells of the inner ear rely on attachments between the actin-based protrusions to activate ion channels, which then transduce signals to afferent neurons. In adherent filopodia, the focal contacts (FCs) integrated with ECM proteins through integrins may regulate integrin-coupled ion channels to achieve signal transduction. Issues that are not understood include the role of Ca(2+) influx in filopodia dynamics and how integrins coordinate or gate signals arising from perturbation of channels by environmental cues.
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Affiliation(s)
- C A Heckman
- Department of Biological Sciences, Bowling Green State University, Bowling Green, OH 43403-0212, USA.
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Tokuo H, Coluccio LM. Myosin-1c regulates the dynamic stability of E-cadherin-based cell-cell contacts in polarized Madin-Darby canine kidney cells. Mol Biol Cell 2013; 24:2820-33. [PMID: 23864705 PMCID: PMC3771945 DOI: 10.1091/mbc.e12-12-0884] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Myo1c knockdown causes defects in E-cadherin localization, E-cadherin binding, and cell–cell contact of Madin–Darby canine kidney cells. Expression of wild-type Myo1c, but not motor-dead mutants or those unable to bind membrane, reverses the phenotype, evidence that Myo1c modulates the assembly/maintenance of adherens junctions. Cooperation between cadherins and the actin cytoskeleton controls the formation and maintenance of cell–cell adhesions in epithelia. We find that the molecular motor protein myosin-1c (Myo1c) regulates the dynamic stability of E-cadherin–based cell–cell contacts. In Myo1c-depleted Madin–Darby canine kidney cells, E-cadherin localization was disorganized and lateral membranes appeared less vertical with convoluted edges versus control cells. In polarized monolayers, Myo1c-knockdown (KD) cells were more sensitive to reduced calcium concentration. Myo1c separated in the same plasma membrane fractions as E-cadherin, and Myo1c KD caused a significant reduction in the amount of E-cadherin recovered in one peak fraction. Expression of green fluorescent protein (GFP)–Myo1c mutants revealed that the phosphatidylinositol-4,5-bisphosphate–binding site is necessary for its localization to cell–cell adhesions, and fluorescence recovery after photobleaching assays with GFP-Myo1c mutants revealed that motor function was important for Myo1c dynamics at these sites. At 18°C, which inhibits vesicle recycling, Myo1c-KD cells accumulated more E-cadherin–positive vesicles in their cytoplasm, suggesting that Myo1c affects E-cadherin endocytosis. Studies with photoactivatable GFP–E-cadherin showed that Myo1c KD reduced the stability of E-cadherin at cell–cell adhesions. We conclude that Myo1c stabilizes E-cadherin at adherens junctions in polarized epithelial cells and that the motor function and ability of Myo1c to bind membrane are critical.
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Affiliation(s)
- Hiroshi Tokuo
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA 02118-2518
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Zhang Y, Kent JW, Olivier M, Ali O, Cerjak D, Broeckel U, Abdou RM, Dyer TD, Comuzzie A, Curran JE, Carless MA, Rainwater DL, Göring HHH, Blangero J, Kissebah AH. A comprehensive analysis of adiponectin QTLs using SNP association, SNP cis-effects on peripheral blood gene expression and gene expression correlation identified novel metabolic syndrome (MetS) genes with potential role in carcinogenesis and systemic inflammation. BMC Med Genomics 2013; 6:14. [PMID: 23628382 PMCID: PMC3643849 DOI: 10.1186/1755-8794-6-14] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Accepted: 04/23/2013] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND Metabolic syndrome (MetS) is an aberration associated with increased risk for cancer and inflammation. Adiponectin, an adipocyte-produced abundant protein hormone, has countering effect on the diabetogenic and atherogenic components of MetS. Plasma levels of adiponectin are negatively correlated with onset of cancer and cancer patient mortality. We previously performed microsatellite linkage analyses using adiponectin as a surrogate marker and revealed two QTLs on chr5 (5p14) and chr14 (14q13). METHODS Using individuals from 85 extended families that contributed to the linkage and who were measured for 42 clinical and biologic MetS phenotypes, we tested QTL-based SNP associations, peripheral white blood cell (PWBC) gene expression, and the effects of cis-acting SNPs on gene expression to discover genomic elements that could affect the pathophysiology and complications of MetS. RESULTS Adiponectin levels were found to be highly intercorrelated phenotypically with the majority of MetS traits. QTL-specific haplotype-tagging SNPs associated with MetS phenotypes were annotated to 14 genes whose function could influence MetS biology as well as oncogenesis or inflammation. These were mechanistically categorized into four groups: cell-cell adhesion and mobility, signal transduction, transcription and protein sorting. Four genes were highly prioritized: cadherin 18 (CDH18), myosin X (MYO10), anchor protein 6 of AMPK (AKAP6), and neuronal PAS domain protein 3 (NPAS3). PWBC expression was detectable only for the following genes with multi-organ or with multi-function properties: NPAS3, MARCH6, MYO10 and FBXL7. Strong evidence of cis-effects on the expression of MYO10 in PWBC was found with SNPs clustered near the gene's transcription start site. MYO10 expression in PWBC was marginally correlated with body composition (p = 0.065) and adipokine levels in the periphery (p = 0.064). Variants of genes AKAP6, NPAS3, MARCH6 and FBXL7 have been previously reported to be associated with insulin resistance, inflammatory markers or adiposity studies using genome-wide approaches whereas associations of CDH18 and MYO10 with MetS traits have not been reported before. CONCLUSIONS Adiponectin QTLs-based SNP association and mRNA expression identified genes that could mediate the association between MetS and cancer or inflammation.
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Affiliation(s)
- Yi Zhang
- TOPS Obesity and Metabolic Research Center, Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
- Human and Molecular Genetics Center, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Jack W Kent
- Department of Genetics, Texas Biomedical Research Institute, San Antonio, Texas, USA
| | - Michael Olivier
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Omar Ali
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Diana Cerjak
- TOPS Obesity and Metabolic Research Center, Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
- Human and Molecular Genetics Center, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Ulrich Broeckel
- Human and Molecular Genetics Center, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Reham M Abdou
- TOPS Obesity and Metabolic Research Center, Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
- Human and Molecular Genetics Center, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Thomas D Dyer
- Department of Genetics, Texas Biomedical Research Institute, San Antonio, Texas, USA
| | - Anthony Comuzzie
- Department of Genetics, Texas Biomedical Research Institute, San Antonio, Texas, USA
| | - Joanne E Curran
- Department of Genetics, Texas Biomedical Research Institute, San Antonio, Texas, USA
| | - Melanie A Carless
- Department of Genetics, Texas Biomedical Research Institute, San Antonio, Texas, USA
| | - David L Rainwater
- Department of Genetics, Texas Biomedical Research Institute, San Antonio, Texas, USA
| | - Harald H H Göring
- Department of Genetics, Texas Biomedical Research Institute, San Antonio, Texas, USA
| | - John Blangero
- Department of Genetics, Texas Biomedical Research Institute, San Antonio, Texas, USA
| | - Ahmed H Kissebah
- TOPS Obesity and Metabolic Research Center, Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
- Human and Molecular Genetics Center, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
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Ngo TX, Nagamori E, Kikuchi T, Shimizu T, Okano T, Taya M, Kino-oka M. Endothelial cell behavior inside myoblast sheets with different thickness. Biotechnol Lett 2013; 35:1001-8. [PMID: 23515892 DOI: 10.1007/s10529-013-1174-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Accepted: 02/27/2013] [Indexed: 02/02/2023]
Abstract
Using a cell sheet stacking method, we developed an in vitro culture system in which green fluorescent protein expressing human umbilical vein endothelial cells (GFP-HUVECs) were cultured under human skeletal muscle myoblast (HSMM) sheets with different layer numbers. Our aim in developing this system was to examine the different endothelial behaviors in the cell sheet. During 96 h of incubation, in monolayer HSMM sheet, HUVECs quickly reached the top of the cell sheet and detached. In three-layered HSMM sheet, HUVECs also migrated to the top layer and formed island-shaped aggregates. In five-layered HSMM sheet, HUVECs migrated into the middle of the cell sheet and formed net-shaped aggregates. In seven-layered HSMM sheet, HUVECs migrated in the basal of the cell sheet and formed sparse net-shaped aggregates. The thickness of the HSMM sheet, which can be controlled by the layer number of the cell sheet, is therefore an important parameter that affects the migration time, encounters, localization, and morphology of HUVECs inside the HSMM sheet.
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Affiliation(s)
- Trung Xuan Ngo
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka, Japan
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Nakayama M, Berger P. Coordination of VEGF receptor trafficking and signaling by coreceptors. Exp Cell Res 2013; 319:1340-7. [PMID: 23499743 DOI: 10.1016/j.yexcr.2013.03.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Revised: 02/25/2013] [Accepted: 03/02/2013] [Indexed: 02/01/2023]
Abstract
During development, regeneration and in certain pathological settings, the vasculature is expanded and remodeled substantially. Proper morphogenesis and function of blood vessels are essential in multicellular organisms. Upon stimulation with growth factors including vascular endothelial growth factors (VEGFs), the activation, internalization and sorting of receptor tyrosine kinases (RTKs) orchestrate developmental processes and the homeostatic maintenance of all organs including the vasculature. Previously, RTK signaling was thought to occur exclusively at the plasma membrane, a process that was subsequently terminated by endocytosis and receptor degradation. However, this model turned out to be an oversimplification and there is now a substantial amount of reports indicating that receptor internalization and trafficking to intracellular compartments depends on coreceptors leading to the activation of specific signaling pathways. Here we review the latest findings concerning endocytosis and intracellular trafficking of VEGFRs. The body of evidence is compelling that VEGF receptor trafficking is coordinated with other proteins such as Neuropilin-1, ephrin-B2, VE-cadherin and protein phosphatases.
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Affiliation(s)
- Masanori Nakayama
- Max-Planck-Institute for Molecular Biomedicine, Department of Tissue Morphogenesis, D-48149 Münster, Germany
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44
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45
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Grantham J, Lassing I, Karlsson R. Controlling the cortical actin motor. PROTOPLASMA 2012; 249:1001-1015. [PMID: 22526202 PMCID: PMC3459087 DOI: 10.1007/s00709-012-0403-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Accepted: 03/21/2012] [Indexed: 05/31/2023]
Abstract
Actin is the essential force-generating component of the microfilament system, which powers numerous motile processes in eukaryotic cells and undergoes dynamic remodeling in response to different internal and external signaling. The ability of actin to polymerize into asymmetric filaments is the inherent property behind the site-directed force-generating capacity that operates during various intracellular movements and in surface protrusions. Not surprisingly, a broad variety of signaling pathways and components are involved in controlling and coordinating the activities of the actin microfilament system in a myriad of different interactions. The characterization of these processes has stimulated cell biologists for decades and has, as a consequence, resulted in a huge body of data. The purpose here is to present a cellular perspective on recent advances in our understanding of the microfilament system with respect to actin polymerization, filament structure and specific folding requirements.
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Affiliation(s)
- Julie Grantham
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Ingrid Lassing
- Department of Cell Biology, Wenner-Gren Institute, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Roger Karlsson
- Department of Cell Biology, Wenner-Gren Institute, Stockholm University, SE-106 91 Stockholm, Sweden
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46
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Abstract
The development of cell-cell junctions was a fundamental step in metazoan evolution, and human health depends on the formation and function of cell junctions. Although it has long been known that actin and conventional myosin have important roles in cell junctions, research has begun to reveal the specific functions of the different forms of conventional myosin. Exciting new data also reveals that a growing number of unconventional myosins have important roles in cell junctions. Experiments showing that cell junctions act as mechanosensors have also provided new impetus to understand the functions of myosins and the forces they exert. In this review we will summarize recent developments on the roles of myosins in cell junctions.
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Affiliation(s)
- Katy C Liu
- Department of Cell and Molecular Physiology; School of Medicine; University of North Carolina at Chapel Hill; Chapel Hill, NC USA
| | - Richard E Cheney
- Department of Cell and Molecular Physiology; School of Medicine; University of North Carolina at Chapel Hill; Chapel Hill, NC USA
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Raines AN, Nagdas S, Kerber ML, Cheney RE. Headless Myo10 is a negative regulator of full-length Myo10 and inhibits axon outgrowth in cortical neurons. J Biol Chem 2012; 287:24873-83. [PMID: 22661706 DOI: 10.1074/jbc.m112.369173] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Myo10 is an unconventional myosin that localizes to and induces filopodia, structures that are critical for growing axons. In addition to the ~240-kDa full-length Myo10, brain expresses a ~165 kDa isoform that lacks a functional motor domain and is known as headless Myo10. We and others have hypothesized that headless Myo10 acts as an endogenous dominant negative of full-length Myo10, but this hypothesis has not been tested, and the function of headless Myo10 remains unknown. We find that cortical neurons express both headless and full-length Myo10 and report the first isoform-specific localization of Myo10 in brain, which shows enrichment of headless Myo10 in regions of proliferating and migrating cells, including the embryonic ventricular zone and the postnatal rostral migratory stream. We also find that headless and full-length Myo10 are expressed in embryonic and neuronal stem cells. To directly test the function of headless and full-length Myo10, we used RNAi specific to each isoform in mouse cortical neuron cultures. Knockdown of full-length Myo10 reduces axon outgrowth, whereas knockdown of headless Myo10 increases axon outgrowth. To test whether headless Myo10 antagonizes full-length Myo10, we coexpressed both isoforms in COS-7 cells, which revealed that headless Myo10 suppresses the filopodia-inducing activity of full-length Myo10. Together, these results demonstrate that headless Myo10 can function as a negative regulator of full-length Myo10 and that the two isoforms of Myo10 have opposing roles in axon outgrowth.
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Affiliation(s)
- Alexander N Raines
- Curriculum in Neurobiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
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Horowitz A, Seerapu HR. Regulation of VEGF signaling by membrane traffic. Cell Signal 2012; 24:1810-20. [PMID: 22617029 DOI: 10.1016/j.cellsig.2012.05.007] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Accepted: 05/09/2012] [Indexed: 01/13/2023]
Abstract
Recent findings have drawn attention to the role of membrane traffic in the signaling of vascular endothelial growth factor (VEGF). The significance of this development stems from the pivotal function of VEGF in vasculogenesis and angiogenesis. The outline of the regulation of VEGF receptor (VEGFR) signaling by membrane traffic is similar to that of the epidermal growth factor receptor (EGFR), a prototype of the intertwining between membrane traffic and signaling. There are, however, unique features in VEGFR signaling that are conferred in part by the involvement of the co-receptor neuropilin (Nrp). Nrp1 and VEGFR2 are integrated into membrane traffic through the adaptor protein synectin, which recruits myosin VI, a molecular motor that drives inward trafficking [17,21,64]. The recent detection of only mild vascular defects in a knockin mouse model that expresses Nrp1 lacking a cytoplasmic domain [104], questions the co-receptor's role in VEGF signaling and membrane traffic. The regulation of endocytosis by ephrin-B2 is another feature unique to VEGR2/3 [18,19], but it awaits a mechanistic explanation. Current models do not fully explain how membrane traffic bridges between VEGFR and the downstream effectors that produce its functional outcome, such as cell migration. VEGF-A appears to accomplish this task in part by recruiting endocytic vesicles carrying RhoA to internalized active VEGFR2 [58].
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Affiliation(s)
- Arie Horowitz
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic Lerner College of Medicine, 9500 Euclid Avenue, Cleveland, OH 44195, USA.
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Yu H, Wang N, Ju X, Yang Y, Sun D, Lai M, Cui L, Sheikh MA, Zhang J, Wang X, Zhu X. PtdIns (3,4,5) P3 recruitment of Myo10 is essential for axon development. PLoS One 2012; 7:e36988. [PMID: 22590642 PMCID: PMC3349655 DOI: 10.1371/journal.pone.0036988] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2012] [Accepted: 04/11/2012] [Indexed: 02/03/2023] Open
Abstract
Myosin X (Myo10) with pleckstrin homology (PH) domains is a motor protein acting in filopodium initiation and extension. However, its potential role has not been fully understood, especially in neuronal development. In the present study the preferential accumulation of Myo10 in axon tips has been revealed in primary culture of hippocampal neurons with the aid of immunofluorescence from anti-Myo10 antibody in combination with anti-Tuj1 antibody as specific marker. Knocking down Myo10 gene transcription impaired outgrowth of axon with loss of Tau-1-positive phenotype. Interestingly, inhibition of actin polymerization by cytochalasin D rescued the defect of axon outgrowth. Furthermore, ectopic expression of Myo10 with enhanced green fluorescence protein (EGFP) labeled Myo10 mutants induced multiple axon-like neurites in a motor-independent way. Mechanism studies demonstrated that the recruitment of Myo10 through its PH domain to phosphatidylinositol (3,4,5)-trisphosphate (PtdIns (3,4,5) P3) was essential for axon formation. In addition, in vivo studies confirmed that Myo10 was required for neuronal morphological transition during radial neuronal migration in the developmental neocortex.
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Affiliation(s)
- Huali Yu
- Key Laboratory of Molecular Epigenetics of Ministry of Education, Institute of Cytology and Genetics, Northeast Normal University, Changchun, China
| | - Nannan Wang
- Key Laboratory of Molecular Epigenetics of Ministry of Education, Institute of Cytology and Genetics, Northeast Normal University, Changchun, China
| | - Xingda Ju
- Key Laboratory of Molecular Epigenetics of Ministry of Education, Institute of Cytology and Genetics, Northeast Normal University, Changchun, China
| | - Yan Yang
- Key Laboratory of Molecular Epigenetics of Ministry of Education, Institute of Cytology and Genetics, Northeast Normal University, Changchun, China
| | - Dong Sun
- Key Laboratory of Molecular Epigenetics of Ministry of Education, Institute of Cytology and Genetics, Northeast Normal University, Changchun, China
| | - Mingming Lai
- Key Laboratory of Molecular Epigenetics of Ministry of Education, Institute of Cytology and Genetics, Northeast Normal University, Changchun, China
| | - Lei Cui
- Key Laboratory of Molecular Epigenetics of Ministry of Education, Institute of Cytology and Genetics, Northeast Normal University, Changchun, China
| | - Muhammad Abid Sheikh
- Key Laboratory of Molecular Epigenetics of Ministry of Education, Institute of Cytology and Genetics, Northeast Normal University, Changchun, China
| | - Jianhua Zhang
- Key Laboratory of Molecular Epigenetics of Ministry of Education, Institute of Cytology and Genetics, Northeast Normal University, Changchun, China
| | - Xingzhi Wang
- Key Laboratory of Molecular Epigenetics of Ministry of Education, Institute of Cytology and Genetics, Northeast Normal University, Changchun, China
| | - Xiaojuan Zhu
- Key Laboratory of Molecular Epigenetics of Ministry of Education, Institute of Cytology and Genetics, Northeast Normal University, Changchun, China
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50
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Abstract
Myosin-X (Myo10) is an unconventional myosin with MyTH4-FERM domains that is best known for its striking localization to the tips of filopodia and its ability to induce filopodia. Although the head domain of Myo10 enables it to function as an actin-based motor, its tail contains binding sites for several molecules with central roles in cell biology, including phosphatidylinositol (3,4,5)-trisphosphate, microtubules and integrins. Myo10 also undergoes fascinating long-range movements within filopodia, which appear to represent a newly recognized system of transport. Myo10 is also unusual in that it is a myosin with important roles in the spindle, a microtubule-based structure. Exciting new studies have begun to reveal the structure and single-molecule properties of this intriguing myosin, as well as its mechanisms of regulation and induction of filopodia. At the cellular and organismal level, growing evidence demonstrates that Myo10 has crucial functions in numerous processes ranging from invadopodia formation to cell migration.
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Affiliation(s)
- Michael L Kerber
- Department of Cell and Molecular Physiology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7545, USA
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