1
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Laiman J, Lin SS, Liu YW. Dynamins in human diseases: differential requirement of dynamin activity in distinct tissues. Curr Opin Cell Biol 2023; 81:102174. [PMID: 37230036 DOI: 10.1016/j.ceb.2023.102174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 04/12/2023] [Accepted: 04/24/2023] [Indexed: 05/27/2023]
Abstract
Dynamin, a 100-kDa GTPase, is one of the most-characterized membrane fission machineries catalyzing vesicle release from plasma membrane during endocytosis. The human genome encodes three dynamins: DNM1, DNM2 and DNM3, with high amino acid similarity but distinct expression patterns. Ever since the discoveries of dynamin mutations associated with human diseases in 2005, dynamin has become a paradigm for studying pathogenic mechanisms of mutant proteins from the aspects of structural biology, cell biology, model organisms as well as therapeutic strategy development. Here, we review the diseases and pathogenic mechanisms caused by mutations of DNM1 and DNM2, focusing on the activity requirement and regulation of dynamins in different tissues.
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Affiliation(s)
- Jessica Laiman
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Shan-Shan Lin
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Ya-Wen Liu
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan; Center of Precision Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan.
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2
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Larsson E, Morén B, McMahon KA, Parton RG, Lundmark R. Dynamin2 functions as an accessory protein to reduce the rate of caveola internalization. J Cell Biol 2023; 222:213853. [PMID: 36729022 PMCID: PMC9929934 DOI: 10.1083/jcb.202205122] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 11/14/2022] [Accepted: 01/10/2023] [Indexed: 02/03/2023] Open
Abstract
Caveolae are small membrane invaginations that generally are stably attached to the plasma membrane. Their release is believed to depend on the GTPase dynamin 2 (Dyn2), in analogy with its role in fission of clathrin-coated vesicles. The mechanistic understanding of caveola fission is, however, sparse. Here, we used microscopy-based tracking of individual caveolae in living cells to determine the role of Dyn2 in caveola dynamics. We report that Dyn2 stably associated with the bulb of a subset of caveolae, but was not required for formation or fission of caveolae. Dyn2-positive caveolae displayed longer plasma membrane duration times, whereas depletion of Dyn2 resulted in shorter duration times and increased caveola fission. The stabilizing role of Dyn2 was independent of its GTPase activity and the caveola stabilizing protein EHD2. Thus, we propose that, in contrast to the current view, Dyn2 is not a core component of the caveolae machinery, but rather functions as an accessory protein that restrains caveola internalization.
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Affiliation(s)
- Elin Larsson
- https://ror.org/05kb8h459Integrative Medical Biology, Umeå University, Umeå, Sweden,Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden
| | - Björn Morén
- https://ror.org/05kb8h459Integrative Medical Biology, Umeå University, Umeå, Sweden,Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden
| | - Kerrie-Ann McMahon
- https://ror.org/00rqy9422Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Robert G. Parton
- https://ror.org/00rqy9422Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia,Centre for Microscopy and Microanalysis, The University of Queensland, Brisbane, Queensland, Australia
| | - Richard Lundmark
- https://ror.org/05kb8h459Integrative Medical Biology, Umeå University, Umeå, Sweden,Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden,Molecular Infection Medicine Sweden, Umeå University, Umeå, Sweden,Correspondence to Richard Lundmark:
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3
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Chen Y, Kang J, Zhen R, Zhang L, Chen C. A genome-wide CRISPR screen identifies the CCT chaperonin as a critical regulator of vesicle trafficking. FASEB J 2023; 37:e22757. [PMID: 36607310 DOI: 10.1096/fj.202201580r] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 12/13/2022] [Accepted: 12/22/2022] [Indexed: 01/07/2023]
Abstract
Vesicle trafficking is a fundamental cellular process that controls the transport of various proteins and cargos between cellular compartments in eukaryotes. Using a combination of genome-wide CRISPR screening in mammalian cells and RNAi screening in Caenorhabditis elegans, we identify chaperonin containing TCP-1 subunit 4 (CCT4) as a critical regulator of protein secretion and vesicle trafficking. In C. elegans, deficiency of cct-4 as well as other CCT subunits impairs the trafficking of endocytic markers in intestinal cells, and this defect resembles that of dyn-1 RNAi worms. Consistent with these findings, the silencing of CCT4 in human cells leads to defective endosomal trafficking, and this defect can be rescued by the dynamin activator Ryngo 1-23. These results suggest that the cytosolic chaperonin CCT may regulate vesicle trafficking by promoting the folding of dynamin in addition to its known substrate tubulin. Our findings establish an essential role for the CCT chaperonin in regulating vesicle trafficking, and provide new insights into the regulation of vesicle trafficking and the cellular function of the cytosolic chaperonin.
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Affiliation(s)
- Yongtian Chen
- MOE Key Laboratory of Biosystems Homeostasis & Protection, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Jing Kang
- MOE Key Laboratory of Biosystems Homeostasis & Protection, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Ru Zhen
- MOE Key Laboratory of Biosystems Homeostasis & Protection, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Liyang Zhang
- MOE Key Laboratory of Biosystems Homeostasis & Protection, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Caiyong Chen
- MOE Key Laboratory of Biosystems Homeostasis & Protection, College of Life Sciences, Zhejiang University, Hangzhou, China
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4
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Odell LR, Robertson MJ, Young KA, McGeachie AB, Quan A, Robinson PJ, McCluskey A. Prodrugs of the Archetypal Dynamin Inhibitor Bis-T-22. ChemMedChem 2022; 17:e202200400. [PMID: 36351775 PMCID: PMC10947042 DOI: 10.1002/cmdc.202200400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 10/06/2022] [Indexed: 11/11/2022]
Abstract
The Bis-T series of compounds comprise some of the most potent inhibitors of dynamin GTPase activity yet reported, e. g., (2E,2'E)-N,N'-(propane-1,3-diyl)bis(2-cyano-3-(3,4-dihydroxyphenyl)acrylamide) (2), Bis-T-22. The catechol moieties are believed to limit cell permeability, rendering these compounds largely inactive in cells. To solve this problem, a prodrug strategy was envisaged and eight ester analogues were synthesised. The shortest and bulkiest esters (acetate and butyl/tert-butyl) were found to be insoluble under physiological conditions, whilst the remaining five were soluble and stable under these conditions. These five were analysed for plasma stability and half-lives ranged from ∼2.3 min (propionic ester 4), increasing with size and bulk, to greater than 24 hr (dimethyl carbamate 10). Similar profiles where observed with the rate of formation of Bis-T-22 with half-lives ranging from ∼25 mins (propionic ester 4). Propionic ester 4 was chosen to undergo further testing and was found to inhibit endocytosis in a dose-dependent manner with IC50 ∼8 μM, suggesting this compound is able to effectively cross the cell membrane where it is rapidly hydrolysed to the desired Bis-T-22 parent compound.
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Affiliation(s)
- Luke R. Odell
- The University of NewcastleUniversity DriveCallaghanNSW 2308Australia
- Present address: Department of Medicinal ChemistryUppsala UniversityBox 57475123UppsalaSweden
| | - Mark J Robertson
- The University of NewcastleUniversity DriveCallaghanNSW 2308Australia
- Present address: Chemistry, College of Science & EngineeringJames Cook UniversityTownsvilleQLD 4814Australia
| | - Kelly A Young
- The University of NewcastleUniversity DriveCallaghanNSW 2308Australia
| | - Andrew B. McGeachie
- Cell Signalling UnitChildren's Medical Research InstituteThe University of Sydney214 Hawkesbury RoadWestmeadNSW 2145Australia
| | - Annie Quan
- Cell Signalling UnitChildren's Medical Research InstituteThe University of Sydney214 Hawkesbury RoadWestmeadNSW 2145Australia
| | - Phillip J. Robinson
- Cell Signalling UnitChildren's Medical Research InstituteThe University of Sydney214 Hawkesbury RoadWestmeadNSW 2145Australia
| | - Adam McCluskey
- The University of NewcastleUniversity DriveCallaghanNSW 2308Australia
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5
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Hamasaki E, Wakita N, Yasuoka H, Nagaoka H, Morita M, Takashima E, Uchihashi T, Takeda T, Abe T, Lee JW, Iimura T, Saleem MA, Ogo N, Asai A, Narita A, Takei K, Yamada H. The Lipid-Binding Defective Dynamin 2 Mutant in Charcot-Marie-Tooth Disease Impairs Proper Actin Bundling and Actin Organization in Glomerular Podocytes. Front Cell Dev Biol 2022; 10:884509. [PMID: 35620056 PMCID: PMC9127447 DOI: 10.3389/fcell.2022.884509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Accepted: 04/06/2022] [Indexed: 11/13/2022] Open
Abstract
Dynamin is an endocytic protein that functions in vesicle formation by scission of invaginated membranes. Dynamin maintains the structure of foot processes in glomerular podocytes by directly and indirectly interacting with actin filaments. However, molecular mechanisms underlying dynamin-mediated actin regulation are largely unknown. Here, biochemical and cell biological experiments were conducted to uncover how dynamin modulates interactions between membranes and actin in human podocytes. Actin-bundling, membrane tubulating, and GTPase activities of dynamin were examined in vitro using recombinant dynamin 2-wild-type (WT) or dynamin 2-K562E, which is a mutant found in Charcot-Marie-Tooth patients. Dynamin 2-WT and dynamin 2-K562E led to the formation of prominent actin bundles with constant diameters. Whereas liposomes incubated with dynamin 2-WT resulted in tubule formation, dynamin 2-K562E reduced tubulation. Actin filaments and liposomes stimulated dynamin 2-WT GTPase activity by 6- and 20-fold, respectively. Actin-filaments, but not liposomes, stimulated dynamin 2-K562E GTPase activity by 4-fold. Self-assembly-dependent GTPase activity of dynamin 2-K562E was reduced to one-third compared to that of dynamin 2-WT. Incubation of liposomes and actin with dynamin 2-WT led to the formation of thick actin bundles, which often bound to liposomes. The interaction between lipid membranes and actin bundles by dynamin 2-K562E was lower than that by dynamin 2-WT. Dynamin 2-WT partially colocalized with stress fibers and actin bundles based on double immunofluorescence of human podocytes. Dynamin 2-K562E expression resulted in decreased stress fiber density and the formation of aberrant actin clusters. Dynamin 2-K562E colocalized with α-actinin-4 in aberrant actin clusters. Reformation of stress fibers after cytochalasin D-induced actin depolymerization and washout was less effective in dynamin 2-K562E-expressing cells than that in dynamin 2-WT. Bis-T-23, a dynamin self-assembly enhancer, was unable to rescue the decreased focal adhesion numbers and reduced stress fiber density induced by dynamin 2-K562E expression. These results suggest that the low affinity of the K562E mutant for lipid membranes, and atypical self-assembling properties, lead to actin disorganization in HPCs. Moreover, lipid-binding and self-assembly of dynamin 2 along actin filaments are required for podocyte morphology and functions. Finally, dynamin 2-mediated interactions between actin and membranes are critical for actin bundle formation in HPCs.
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Affiliation(s)
- Eriko Hamasaki
- Department of Neuroscience, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Natsuki Wakita
- Department of Neuroscience, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Hiroki Yasuoka
- Department of Neuroscience, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Hikaru Nagaoka
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Japan
| | - Masayuki Morita
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Japan
| | - Eizo Takashima
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Japan
| | | | - Tetsuya Takeda
- Department of Neuroscience, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Tadashi Abe
- Department of Neuroscience, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Ji-Won Lee
- Department of Pharmacology, Faculty and Graduate School of Dental Medicine, Hokkaido University, Sapporo, Japan
| | - Tadahiro Iimura
- Department of Pharmacology, Faculty and Graduate School of Dental Medicine, Hokkaido University, Sapporo, Japan
| | - Moin A Saleem
- Bristol Renal, Translational Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Naohisa Ogo
- Center for Drug Discovery, Graduate School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan
| | - Akira Asai
- Center for Drug Discovery, Graduate School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan
| | - Akihiro Narita
- Graduate School of Science, Nagoya University, Nagoya, Japan
| | - Kohji Takei
- Department of Neuroscience, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Hiroshi Yamada
- Department of Neuroscience, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
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6
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Nabb AT, Bentley M. NgCAM and VAMP2 reveal that direct delivery and dendritic degradation maintain axonal polarity. Mol Biol Cell 2022; 33:ar3. [PMID: 34731031 PMCID: PMC8886818 DOI: 10.1091/mbc.e21-08-0425] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Neurons are polarized cells of extreme scale and compartmentalization. To fulfill their role in electrochemical signaling, axons must maintain a specific complement of membrane proteins. Despite being the subject of considerable attention, the trafficking pathway of axonal membrane proteins is not well understood. Two pathways, direct delivery and transcytosis, have been proposed. Previous studies reached contradictory conclusions about which of these mediates delivery of axonal membrane proteins to their destination, in part because they evaluated long-term distribution changes and not vesicle transport. We developed a novel strategy to selectively label vesicles in different trafficking pathways and determined the trafficking of two canonical axonal membrane proteins, neuron-glia cell adhesion molecule and vesicle-associated membrane protein-2. Results from detailed quantitative analyses of transporting vesicles differed substantially from previous studies and found that axonal membrane proteins overwhelmingly undergo direct delivery. Transcytosis plays only a minor role in axonal delivery of these proteins. In addition, we identified a novel pathway by which wayward axonal proteins that reach the dendritic plasma membrane are targeted to lysosomes. These results redefine how axonal proteins achieve their polarized distribution, a crucial requirement for elucidating the underlying molecular mechanisms.
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Affiliation(s)
- Alec T. Nabb
- Department of Biological Sciences and the Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180
| | - Marvin Bentley
- Department of Biological Sciences and the Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180,*Address correspondence to: Marvin Bentley ()
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7
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Sun EW, Matusica D, Wattchow DA, McCluskey A, Robinson PJ, Keating DJ. Dynamin regulates L cell secretion in human gut. Mol Cell Endocrinol 2021; 535:111398. [PMID: 34274446 DOI: 10.1016/j.mce.2021.111398] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 06/01/2021] [Accepted: 07/13/2021] [Indexed: 11/16/2022]
Abstract
BACKGROUND The mechanochemical enzyme dynamin mediates endocytosis and regulates neuroendocrine cell exocytosis. Enteroendocrine L cells co-secrete the anorectic gut hormones glucagon-like peptide 1 (GLP-1) and peptide YY (PYY) postprandially and is a potential therapeutic target for metabolic diseases. In the present study, we aimed to determine if dynamin is implicated in human L cell secretion. METHODS Western blot was performed on the murine L cell line GLUTag. Static incubation of human colonic mucosae with activators and inhibitors of dynamin was carried out. GLP-1 and PYY contents of the secretion supernatants were assayed using ELISA. RESULTS AND CONCLUSION s: Both dynamin I and II are expressed in GLUTag cells. The dynamin activator Ryngo 1-23 evoked significant GLP-1 and PYY release from human colonic mucosae while the dynamin inhibitor Dynole 3-42 significantly inhibited release triggered by known L cell secretagogues. Thus, the cell signaling regulator dynamin is able to bi-directionally regulate L cell hormone secretion in the human gut and may represent a novel target for gastrointestinal-targeted metabolic drug development.
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Affiliation(s)
- Emily Wl Sun
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA, Australia
| | - Dusan Matusica
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA, Australia
| | | | - Adam McCluskey
- Chemistry, School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW, Australia
| | - Philip J Robinson
- Cell Signalling Unit, Children's Medical Research Institute, The University of Sydney, Westmead, NSW, Australia
| | - Damien J Keating
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA, Australia.
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8
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Sever S. Role of actin cytoskeleton in podocytes. Pediatr Nephrol 2021; 36:2607-2614. [PMID: 33188449 PMCID: PMC8116355 DOI: 10.1007/s00467-020-04812-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 09/14/2020] [Accepted: 10/05/2020] [Indexed: 12/11/2022]
Abstract
The selectivity of the glomerular filter is established by physical, chemical, and signaling interplay among its three core constituents: glomerular endothelial cells, the glomerular basement membrane, and podocytes. Functional impairment or injury of any of these three components can lead to proteinuria. Podocytes are injured in many forms of human and experimental glomerular disease, including minimal change disease, focal segmental glomerulosclerosis, and diabetes mellitus. One of the earliest signs of podocyte injury is loss of their distinct structure, which is driven by dysregulated dynamics of the actin cytoskeleton. The status of the actin cytoskeleton in podocytes depends on a set of actin binding proteins, nucleators and inhibitors of actin polymerization, and regulatory GTPases. Mutations that alter protein function in each category have been implicated in glomerular diseases in humans and animal models. In addition, a growing body of studies suggest that pharmacological modifications of the actin cytoskeleton have the potential to become novel therapeutics for podocyte-dependent chronic kidney diseases. This review presents an overview of the essential proteins that establish actin cytoskeleton in podocytes and studies demonstrating the feasibility of drugging actin cytoskeleton in kidney diseases.
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Affiliation(s)
- Sanja Sever
- Harvard Medical School and Massachusetts General Hospital, Boston, MA, USA.
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9
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Trochet D, Bitoun M. A review of Dynamin 2 involvement in cancers highlights a promising therapeutic target. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2021; 40:238. [PMID: 34294140 PMCID: PMC8296698 DOI: 10.1186/s13046-021-02045-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 07/15/2021] [Indexed: 12/23/2022]
Abstract
Dynamin 2 (DNM2) is an ubiquitously expressed large GTPase well known for its role in vesicle formation in endocytosis and intracellular membrane trafficking also acting as a regulator of cytoskeletons. During the last two decades, DNM2 involvement, through mutations or overexpression, emerged in an increasing number of cancers and often associated with poor prognosis. A wide panel of DNM2-dependent processes was described in cancer cells which explains DNM2 contribution to cancer pathomechanisms. First, DNM2 dysfunction may promote cell migration, invasion and metastasis. Second, DNM2 acts on intracellular signaling pathways fostering tumor cell proliferation and survival. Relative to these roles, DNM2 was demonstrated as a therapeutic target able to reduce cell proliferation, induce apoptosis, and reduce the invasive phenotype in a wide range of cancer cells in vitro. Moreover, proofs of concept of therapy by modulation of DNM2 expression was also achieved in vivo in several animal models. Consequently, DNM2 appears as a promising molecular target for the development of anti-invasive agents and the already provided proofs of concept in animal models represent an important step of preclinical development.
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Affiliation(s)
- Delphine Trochet
- Centre de Recherche en Myologie, Sorbonne Université, Inserm, UMRS 974, Institut de Myologie, F-75013, Paris, France
| | - Marc Bitoun
- Centre de Recherche en Myologie, Sorbonne Université, Inserm, UMRS 974, Institut de Myologie, F-75013, Paris, France.
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Chemical Inhibitors of Dynamin Exert Differential Effects in VEGF Signaling. Cells 2021; 10:cells10050997. [PMID: 33922806 PMCID: PMC8145957 DOI: 10.3390/cells10050997] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 04/19/2021] [Accepted: 04/20/2021] [Indexed: 01/10/2023] Open
Abstract
VEGFR2 is the main receptor and mediator of the vasculogenic and angiogenic activity of VEGF. Activated VEGFR2 internalizes through clathrin-mediated endocytosis and macropinocytosis. As dynamin is a key regulator of the clathrin pathway, chemical inhibitors of dynamin are commonly used to assess the role of the clathrin route in receptor signaling. However, drugs may also exert off-target effects. Here, we compare the effects of three dynamin inhibitors, dynasore, dyngo 4a and dynole, on VEGFR2 internalization and signaling. Although these drugs consistently inhibit clathrin-mediated endocytosis of both transferrin (a typical cargo of this route) and VEGFR2, surprisingly, they exert contradictory effects in receptor signaling. Thus, while dynasore has no effect on phosphorylation of VEGFR2, the other two drugs are strong inhibitors. Furthermore, although dyngo does not interfere with phosphorylation of Akt, dynasore and dynole have a strong inhibitory effect. These inconsistent effects suggest that the above dynamin blockers, besides inhibiting dynamin-dependent endocytosis of VEGFR2, exert additional inhibitory effects on signaling that are independent of endocytosis; i.e., they are due to off-target effects. Using a recently developed protocol, we comparatively validate the specificity of two endocytic inhibitors, dynasore and EIPA. Our findings highlight the importance of assessing whether the effect of an endocytic drug on signaling is specifically due to its interference with endocytosis or due to off-targets.
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11
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La TM, Tachibana H, Li SA, Abe T, Seiriki S, Nagaoka H, Takashima E, Takeda T, Ogawa D, Makino SI, Asanuma K, Watanabe M, Tian X, Ishibe S, Sakane A, Sasaki T, Wada J, Takei K, Yamada H. Dynamin 1 is important for microtubule organization and stabilization in glomerular podocytes. FASEB J 2020; 34:16449-16463. [PMID: 33070431 DOI: 10.1096/fj.202001240rr] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 09/24/2020] [Accepted: 10/06/2020] [Indexed: 11/11/2022]
Abstract
Dynamin 1 is a neuronal endocytic protein that participates in vesicle formation by scission of invaginated membranes. Dynamin 1 is also expressed in the kidney; however, its physiological significance to this organ remains unknown. Here, we show that dynamin 1 is crucial for microtubule organization and stabilization in glomerular podocytes. By immunofluorescence and immunoelectron microscopy, dynamin 1 was concentrated at microtubules at primary processes in rat podocytes. By immunofluorescence of differentiated mouse podocytes (MPCs), dynamin 1 was often colocalized with microtubule bundles, which radially arranged toward periphery of expanded podocyte. In dynamin 1-depleted MPCs by RNAi, α-tubulin showed a dispersed linear filament-like localization, and microtubule bundles were rarely observed. Furthermore, dynamin 1 depletion resulted in the formation of discontinuous, short acetylated α-tubulin fragments, and the decrease of microtubule-rich protrusions. Dynamins 1 and 2 double-knockout podocytes showed dispersed acetylated α-tubulin and rare protrusions. In vitro, dynamin 1 polymerized around microtubules and cross-linked them into bundles, and increased their resistance to the disassembly-inducing reagents Ca2+ and podophyllotoxin. In addition, overexpression and depletion of dynamin 1 in MPCs increased and decreased the nocodazole resistance of microtubules, respectively. These results suggest that dynamin 1 supports the microtubule bundle formation and participates in the stabilization of microtubules.
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Affiliation(s)
- The Mon La
- Department of Neuroscience, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Hiromi Tachibana
- Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Shun-Ai Li
- Center for Innovative Clinical Medicine, Okayama University Hospital, Okayama, Japan
| | - Tadashi Abe
- Department of Neuroscience, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Sayaka Seiriki
- Department of Neuroscience, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Hikaru Nagaoka
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Japan
| | - Eizo Takashima
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Japan
| | - Tetsuya Takeda
- Department of Neuroscience, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Daisuke Ogawa
- Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Shin-Ichi Makino
- Department of Nephrology, Graduate School of Medicine, Chiba University, Chiba-shi, Japan
| | - Katsuhiko Asanuma
- Department of Nephrology, Graduate School of Medicine, Chiba University, Chiba-shi, Japan
| | - Masami Watanabe
- Center for Innovative Clinical Medicine, Okayama University Hospital, Okayama, Japan
| | - Xuefei Tian
- Department of Internal Medicine, Section of Nephrology, Yale University School of Medicine, New Haven, CT, USA
| | - Shuta Ishibe
- Department of Internal Medicine, Section of Nephrology, Yale University School of Medicine, New Haven, CT, USA
| | - Ayuko Sakane
- Department of Biochemistry, Tokushima University Graduate School of Medical Sciences, Tokushima, Japan.,Department of Interdisciplinary Researches for Medicine and Photonics, Institute of Post-LED Photonics, Tokushima, Japan
| | - Takuya Sasaki
- Department of Biochemistry, Tokushima University Graduate School of Medical Sciences, Tokushima, Japan
| | - Jun Wada
- Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Kohji Takei
- Department of Neuroscience, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Hiroshi Yamada
- Department of Neuroscience, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
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12
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Blaine J, Dylewski J. Regulation of the Actin Cytoskeleton in Podocytes. Cells 2020; 9:cells9071700. [PMID: 32708597 PMCID: PMC7408282 DOI: 10.3390/cells9071700] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 06/30/2020] [Accepted: 07/07/2020] [Indexed: 12/13/2022] Open
Abstract
Podocytes are an integral part of the glomerular filtration barrier, a structure that prevents filtration of large proteins and macromolecules into the urine. Podocyte function is dependent on actin cytoskeleton regulation within the foot processes, structures that link podocytes to the glomerular basement membrane. Actin cytoskeleton dynamics in podocyte foot processes are complex and regulated by multiple proteins and other factors. There are two key signal integration and structural hubs within foot processes that regulate the actin cytoskeleton: the slit diaphragm and focal adhesions. Both modulate actin filament extension as well as foot process mobility. No matter what the initial cause, the final common pathway of podocyte damage is dysregulation of the actin cytoskeleton leading to foot process retraction and proteinuria. Disruption of the actin cytoskeleton can be due to acquired causes or to genetic mutations in key actin regulatory and signaling proteins. Here, we describe the major structural and signaling components that regulate the actin cytoskeleton in podocytes as well as acquired and genetic causes of actin dysregulation.
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Affiliation(s)
- Judith Blaine
- Renal Division, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA;
| | - James Dylewski
- Renal Division, University of Colorado Anschutz Medical Campus and Denver Health Medical Center, Aurora, CO 80045, USA
- Correspondence: ; Tel.: +303-724-4841
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13
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Albanesi JP, Barylko B, DeMartino GN, Jameson DM. Palmitoylated Proteins in Dendritic Spine Remodeling. Front Synaptic Neurosci 2020; 12:22. [PMID: 32655390 PMCID: PMC7325885 DOI: 10.3389/fnsyn.2020.00022] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 05/12/2020] [Indexed: 12/14/2022] Open
Abstract
Activity-responsive changes in the actin cytoskeleton are required for the biogenesis, motility, and remodeling of dendritic spines. These changes are governed by proteins that regulate the polymerization, depolymerization, bundling, and branching of actin filaments. Thus, processes that have been extensively characterized in the context of non-neuronal cell shape change and migration are also critical for learning and memory. In this review article, we highlight actin regulatory proteins that associate, at least transiently, with the dendritic plasma membrane. All of these proteins have been shown, either in directed studies or in high-throughput screens, to undergo palmitoylation, a potentially reversible, and stimulus-dependent cysteine modification. Palmitoylation increases the affinity of peripheral proteins for the membrane bilayer and contributes to their subcellular localization and recruitment to cholesterol-rich membrane microdomains.
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Affiliation(s)
- Joseph P. Albanesi
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Barbara Barylko
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - George N. DeMartino
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - David M. Jameson
- Department of Cell and Molecular Biology, University of Hawaii, Honolulu, HI, United States
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14
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Dana D, Pathak SK. A Review of Small Molecule Inhibitors and Functional Probes of Human Cathepsin L. Molecules 2020; 25:E698. [PMID: 32041276 PMCID: PMC7038230 DOI: 10.3390/molecules25030698] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 01/29/2020] [Accepted: 02/04/2020] [Indexed: 01/06/2023] Open
Abstract
Human cathepsin L belongs to the cathepsin family of proteolytic enzymes with primarily an endopeptidase activity. Although its primary functions were originally thought to be only of a housekeeping enzyme that degraded intracellular and endocytosed proteins in lysosome, numerous recent studies suggest that it plays many critical and specific roles in diverse cellular settings. Not surprisingly, the dysregulated function of cathepsin L has manifested itself in several human diseases, making it an attractive target for drug development. Unfortunately, several redundant and isoform-specific functions have recently emerged, adding complexities to the drug discovery process. To address this, a series of chemical biology tools have been developed that helped define cathepsin L biology with exquisite precision in specific cellular contexts. This review elaborates on the recently developed small molecule inhibitors and probes of human cathepsin L, outlining their mechanisms of action, and describing their potential utilities in dissecting unknown function.
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Affiliation(s)
- Dibyendu Dana
- Chemistry and Biochemistry Department, Queens College of The City University of New York, 65-30 Kissena Blvd, Flushing, NY 11367, USA
- Ph.D. Program in Biochemistry, The Graduate Center of the City University of New York (CUNY), 365 5th Ave, New York, NY 10016, USA
| | - Sanjai K. Pathak
- Chemistry and Biochemistry Department, Queens College of The City University of New York, 65-30 Kissena Blvd, Flushing, NY 11367, USA
- Ph.D. Program in Biochemistry, The Graduate Center of the City University of New York (CUNY), 365 5th Ave, New York, NY 10016, USA
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15
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Dynamin-Like Protein B of Dictyostelium Contributes to Cytokinesis Cooperatively with Other Dynamins. Cells 2019; 8:cells8080781. [PMID: 31357517 PMCID: PMC6721605 DOI: 10.3390/cells8080781] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 07/19/2019] [Accepted: 07/25/2019] [Indexed: 01/31/2023] Open
Abstract
Dynamin is a large GTPase responsible for diverse cellular processes, such as endocytosis, division of organelles, and cytokinesis. The social amoebozoan, Dictyostelium discoideum, has five dynamin-like proteins: dymA, dymB, dlpA, dlpB, and dlpC. DymA, dlpA, or dlpB-deficient cells exhibited defects in cytokinesis. DlpA and dlpB were found to colocalize at cleavage furrows from the early phase, and dymA localized at the intercellular bridge connecting the two daughter cells, indicating that these dynamins contribute to cytokinesis at distinct dividing stages. Total internal reflection fluorescence microscopy revealed that dlpA and dlpB colocalized at individual dots at the furrow cortex. However, dlpA and dlpB did not colocalize with clathrin, suggesting that they are not involved in clathrin-mediated endocytosis. The fact that dlpA did not localize at the furrow in dlpB null cells and vice versa, as well as other several lines of evidence, suggests that hetero-oligomerization of dlpA and dlpB is required for them to bind to the furrow. The hetero-oligomers directly or indirectly associate with actin filaments, stabilizing them in the contractile rings. Interestingly, dlpA, but not dlpB, accumulated at the phagocytic cups independently of dlpB. Our results suggest that the hetero-oligomers of dlpA and dlpB contribute to cytokinesis cooperatively with dymA.
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16
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Rafiq NBM, Grenci G, Lim CK, Kozlov MM, Jones GE, Viasnoff V, Bershadsky AD. Forces and constraints controlling podosome assembly and disassembly. Philos Trans R Soc Lond B Biol Sci 2019; 374:20180228. [PMID: 31431172 DOI: 10.1098/rstb.2018.0228] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Podosomes are a singular category of integrin-mediated adhesions important in the processes of cell migration, matrix degradation and cancer cell invasion. Despite a wealth of biochemical studies, the effects of mechanical forces on podosome integrity and dynamics are poorly understood. Here, we show that podosomes are highly sensitive to two groups of physical factors. First, we describe the process of podosome disassembly induced by activation of myosin-IIA filament assembly. Next, we find that podosome integrity and dynamics depends upon membrane tension and can be experimentally perturbed by osmotic swelling and deoxycholate treatment. We have also found that podosomes can be disrupted in a reversible manner by single or cyclic radial stretching of the substratum. We show that disruption of podosomes induced by osmotic swelling is independent of myosin-II filaments. The inhibition of the membrane sculpting protein, dynamin-II, but not clathrin, resulted in activation of myosin-IIA filament formation and disruption of podosomes. The effect of dynamin-II inhibition on podosomes was, however, independent of myosin-II filaments. Moreover, formation of organized arrays of podosomes in response to microtopographic cues (the ridges with triangular profile) was not accompanied by reorganization of myosin-II filaments. Thus, mechanical elements such as myosin-II filaments and factors affecting membrane tension/sculpting independently modulate podosome formation and dynamics, underlying a versatile response of these adhesion structures to intracellular and extracellular cues. This article is part of a discussion meeting issue 'Forces in cancer: interdisciplinary approaches in tumour mechanobiology'.
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Affiliation(s)
- Nisha Bte Mohd Rafiq
- Mechanobiology Institute, National University of Singapore, Singapore 117411, Republic of Singapore.,Randall Centre for Cell and Molecular Biophysics, King's College London, London SE1 1UL, UK
| | - Gianluca Grenci
- Mechanobiology Institute, National University of Singapore, Singapore 117411, Republic of Singapore.,Biomedical Engineering Department, National University of Singapore, 4 Engineering Drive 3, Singapore 117583, Republic of Singapore
| | - Cheng Kai Lim
- Mechanobiology Institute, National University of Singapore, Singapore 117411, Republic of Singapore
| | - Michael M Kozlov
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, 69978 Tel Aviv, Israel
| | - Gareth E Jones
- Randall Centre for Cell and Molecular Biophysics, King's College London, London SE1 1UL, UK
| | - Virgile Viasnoff
- Mechanobiology Institute, National University of Singapore, Singapore 117411, Republic of Singapore.,CNRS UMI 3639, 5A Engineering Drive 1, Singapore 117411, Republic of Singapore.,Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543, Republic of Singapore
| | - Alexander D Bershadsky
- Mechanobiology Institute, National University of Singapore, Singapore 117411, Republic of Singapore.,Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel
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17
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Chuang MC, Lin SS, Ohniwa RL, Lee GH, Su YA, Chang YC, Tang MJ, Liu YW. Tks5 and Dynamin-2 enhance actin bundle rigidity in invadosomes to promote myoblast fusion. J Cell Biol 2019; 218:1670-1685. [PMID: 30894403 PMCID: PMC6504888 DOI: 10.1083/jcb.201809161] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 01/22/2019] [Accepted: 03/04/2019] [Indexed: 12/12/2022] Open
Abstract
Skeletal muscle development requires the cell-cell fusion of differentiated myoblasts to form muscle fibers. The actin cytoskeleton is known to be the main driving force for myoblast fusion; however, how actin is organized to direct intercellular fusion remains unclear. Here we show that an actin- and dynamin-2-enriched protrusive structure, the invadosome, is required for the fusion process of myogenesis. Upon differentiation, myoblasts acquire the ability to form invadosomes through isoform switching of a critical invadosome scaffold protein, Tks5. Tks5 directly interacts with and recruits dynamin-2 to the invadosome and regulates its assembly around actin filaments to strengthen the stiffness of dynamin-actin bundles and invadosomes. These findings provide a mechanistic framework for the acquisition of myogenic fusion machinery during myogenesis and reveal a novel structural function for Tks5 and dynamin-2 in organizing actin filaments in the invadosome to drive membrane fusion.
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Affiliation(s)
- Mei-Chun Chuang
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Shan-Shan Lin
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Ryosuke L Ohniwa
- Faculty of Medicine, University of Tsukuba, Tsukuba, Japan.,Center for Biotechnology, National Taiwan University, Taipei, Taiwan
| | - Gang-Hui Lee
- International Center of Wound Repair and Regeneration, National Cheng Kung University, Tainan, Taiwan
| | - You-An Su
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Yu-Chen Chang
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Ming-Jer Tang
- International Center of Wound Repair and Regeneration, National Cheng Kung University, Tainan, Taiwan.,Department of Physiology, Medical College, National Cheng Kung University, Tainan, Taiwan
| | - Ya-Wen Liu
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan .,Center of Precision Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
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18
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Pfanzelter J, Mostowy S, Way M. Septins suppress the release of vaccinia virus from infected cells. J Cell Biol 2018; 217:2911-2929. [PMID: 29921601 PMCID: PMC6080921 DOI: 10.1083/jcb.201708091] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 04/08/2018] [Accepted: 05/14/2018] [Indexed: 01/01/2023] Open
Abstract
Septins are conserved components of the cytoskeleton that play important roles in many fundamental cellular processes including division, migration, and membrane trafficking. Septins can also inhibit bacterial infection by forming cage-like structures around pathogens such as Shigella We found that septins are recruited to vaccinia virus immediately after its fusion with the plasma membrane during viral egress. RNA interference-mediated depletion of septins increases virus release and cell-to-cell spread, as well as actin tail formation. Live cell imaging reveals that septins are displaced from the virus when it induces actin polymerization. Septin loss, however, depends on the recruitment of the SH2/SH3 adaptor Nck, but not the activity of the Arp2/3 complex. Moreover, it is the recruitment of dynamin by the third Nck SH3 domain that displaces septins from the virus in a formin-dependent fashion. Our study demonstrates that septins suppress vaccinia release by "entrapping" the virus at the plasma membrane. This antiviral effect is overcome by dynamin together with formin-mediated actin polymerization.
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Affiliation(s)
- Julia Pfanzelter
- Cellular Signalling and Cytoskeletal Function Laboratory, The Francis Crick Institute, London, England, UK
| | - Serge Mostowy
- Section of Microbiology, Medical Research Council Centre for Molecular Bacteriology and Infection, Imperial College London, London, England, UK,Department of Immunology and Infection, London School of Hygiene & Tropical Medicine, London, England, UK
| | - Michael Way
- Cellular Signalling and Cytoskeletal Function Laboratory, The Francis Crick Institute, London, England, UK
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19
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Yamamura H, Suzuki Y, Yamamura H, Asai K, Giles W, Imaizumi Y. Hypoxic stress upregulates Kir2.1 expression by a pathway including hypoxic-inducible factor-1α and dynamin2 in brain capillary endothelial cells. Am J Physiol Cell Physiol 2018; 315:C202-C213. [DOI: 10.1152/ajpcell.00154.2017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Brain capillary endothelial cells (BCECs) play a central role in maintenance of blood-brain barrier (BBB) function and, therefore, are essential for central nervous system homeostasis and integrity. Although brain ischemia damages BCECs and causes disruption of BBB, the related influence of hypoxia on BCECs is not well understood. Hypoxic stress can upregulate functional expression of specific K+ currents in endothelial cells, e.g., Kir2.1 channels without any alterations in the mRNA level, in t-BBEC117, a cell line derived from bovine BCECs. The hyperpolarization of membrane potential due to Kir2.1 channel upregulation significantly facilitates cell proliferation. In the present study, the mechanisms underlying the hypoxia-induced Kir2.1 upregulation was examined. We emphasize the involvement of dynamin2, a protein known to be involved in a number of surface expression pathways. Hypoxic culture upregulated dynamin2 expression in t-BBEC117 cells. The inhibition of dynamin2 by Dynasore canceled hypoxia-induced upregulation of Kir2.1 currents by reducing surface expression. On the contrary, Kir2.1 currents and proteins in t-BBEC117 cultured under normoxia were increased by overexpression of dynamin2, but not by dominant-negative dynamin2. Molecular imaging based on bimolecular fluorescence complementation, double-immunostaining, and coimmunoprecipitation assays revealed that dynamin2 can directly bind to the Kir2.1 channel. Moreover, hypoxic culture downregulated hypoxic-inducible factor-1α (HIF-1α) expression. Knockdown of HIF-1α increased dynamin2 expression in t-BBEC117 cells, in both normoxic and hypoxic culture conditions. In summary, our results demonstrated that hypoxia downregulates HIF-1α, increases dynamin2 expression, and facilitates Kir2.1 surface expression, resulting in hyperpolarization of membrane potential and subsequent increase in Ca2+ influx in BCECs.
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Affiliation(s)
- Hideto Yamamura
- Department of Molecular and Cellular Pharmacology, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
| | - Yoshiaki Suzuki
- Department of Molecular and Cellular Pharmacology, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
| | - Hisao Yamamura
- Department of Molecular and Cellular Pharmacology, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
| | - Kiyofumi Asai
- Department of Molecular Neurobiology, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
| | - Wayne Giles
- Faculties of Kinesiology and Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Yuji Imaizumi
- Department of Molecular and Cellular Pharmacology, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
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20
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Actin dynamics at focal adhesions: a common endpoint and putative therapeutic target for proteinuric kidney diseases. Kidney Int 2018; 93:1298-1307. [PMID: 29678354 DOI: 10.1016/j.kint.2017.12.028] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 12/07/2017] [Accepted: 12/13/2017] [Indexed: 01/02/2023]
Abstract
Proteinuria encompasses diverse causes including both genetic diseases and acquired forms such as diabetic and hypertensive nephropathy. The basis of proteinuria is a disturbance in size selectivity of the glomerular filtration barrier, which largely depends on the podocyte: a terminally differentiated epithelial cell type covering the outer surface of the glomerulus. Compromised podocyte structure is one of the earliest signs of glomerular injury. The phenotype of diverse animal models and podocyte cell culture firmly established the essential role of the actin cytoskeleton in maintaining functional podocyte structure. Podocyte foot processes, actin-based membrane extensions, contain 2 molecularly distinct "hubs" that control actin dynamics: a slit diaphragm and focal adhesions. Although loss of foot processes encompasses disassembly of slit diaphragm multiprotein complexes, as long as cells are attached to the glomerular basement membrane, focal adhesions will be the sites in which stress due to filtration flow is counteracted by forces generated by the actin network in foot processes. Numerous studies within last 20 years have identified actin binding and regulatory proteins as well as integrins as essential components of signaling and actin dynamics at focal adhesions in podocytes, suggesting that some of them may become novel, druggable targets for proteinuric kidney diseases. Here we review evidence supporting the idea that current treatments for chronic kidney diseases beneficially and directly target the podocyte actin cytoskeleton associated with focal adhesions and suggest that therapeutic reagents that target the focal adhesion-regulated actin cytoskeleton in foot processes have potential to modernize treatments for chronic kidney diseases.
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21
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Ferguson R, Subramanian V. The cellular uptake of angiogenin, an angiogenic and neurotrophic factor is through multiple pathways and largely dynamin independent. PLoS One 2018; 13:e0193302. [PMID: 29486010 PMCID: PMC5828446 DOI: 10.1371/journal.pone.0193302] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 02/08/2018] [Indexed: 01/25/2023] Open
Abstract
Angiogenin (ANG), a member of the RNase superfamily (also known as RNase 5) has neurotrophic, neuroprotective and angiogenic activities. Recently it has also been shown to be important in stem cell homeostasis. Mutations in ANG are associated with neurodegenerative diseases such as Amyotrophic Lateral Sclerosis (ALS) and Fronto-temporal dementia (FTD). ANG is a secreted protein which is taken up by cells and translocated to the nucleus. However, the import pathway/s through which ANG is taken up is/are still largely unclear. We have characterised the uptake of ANG in neuronal, astrocytic and microglial cell lines as well as primary neurons and astrocytes using pharmacological agents as well as dominant negative dynamin and Rab5 to perturb uptake and intracellular trafficking. We find that uptake of ANG is largely clathrin/dynamin independent and microtubule depolymerisation has a marginal effect. Perturbation of membrane ruffling and macropinocytosis significantly inhibited ANG uptake suggesting an uptake mechanism similar to RNase A. Our findings shed light on why mutations which do not overtly affect RNase activity but cause impaired localization are associated with neurodegenerative disease.
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Affiliation(s)
- Ross Ferguson
- Department of Biology and Biochemistry, University of Bath, Bath, United Kingdom
| | - Vasanta Subramanian
- Department of Biology and Biochemistry, University of Bath, Bath, United Kingdom
- * E-mail:
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22
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Niedergang F, Grinstein S. How to build a phagosome: new concepts for an old process. Curr Opin Cell Biol 2018; 50:57-63. [DOI: 10.1016/j.ceb.2018.01.009] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 01/16/2018] [Accepted: 01/20/2018] [Indexed: 12/19/2022]
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23
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Wilkerson JR, Albanesi JP, Huber KM. Roles for Arc in metabotropic glutamate receptor-dependent LTD and synapse elimination: Implications in health and disease. Semin Cell Dev Biol 2017; 77:51-62. [PMID: 28969983 DOI: 10.1016/j.semcdb.2017.09.035] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 09/21/2017] [Accepted: 09/26/2017] [Indexed: 10/18/2022]
Abstract
The Arc gene is robustly transcribed in specific neural ensembles in response to experience-driven activity. Upon induction, Arc mRNA is transported to dendrites, where it can be rapidly and locally translated by activation of metabotropic glutamate receptors (mGluR1/5). mGluR-induced dendritic synthesis of Arc is implicated in weakening or elimination of excitatory synapses by triggering endocytosis of postsynaptic AMPARs in both hippocampal CA1 and cerebellar Purkinje neurons. Importantly, CA1 neurons with experience-induced Arc mRNA are susceptible, or primed for mGluR-induced long-term synaptic depression (mGluR-LTD). Here we review mechanisms and function of Arc in mGluR-LTD and synapse elimination and propose roles for these forms of plasticity in Arc-dependent formation of sparse neural representations of learned experience. We also discuss accumulating evidence linking dysregulation of Arc and mGluR-LTD in human cognitive disorders such as intellectual disability, autism and Alzheimer's disease.
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Affiliation(s)
- Julia R Wilkerson
- Departments of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX 75390, United States
| | - Joseph P Albanesi
- Departments of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390, United States
| | - Kimberly M Huber
- Departments of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX 75390, United States.
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24
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Eich ML, Dembla E, Wahl S, Dembla M, Schwarz K, Schmitz F. The Calcineurin-Binding, Activity-Dependent Splice Variant Dynamin1xb Is Highly Enriched in Synapses in Various Regions of the Central Nervous System. Front Mol Neurosci 2017; 10:230. [PMID: 28790889 PMCID: PMC5524891 DOI: 10.3389/fnmol.2017.00230] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2017] [Accepted: 07/06/2017] [Indexed: 12/22/2022] Open
Abstract
In the present study, we generated and characterized a splice site-specific monoclonal antibody that selectively detects the calcineurin-binding dynamin1 splice variant dynamin1xb. Calcineurin is a Ca2+-regulated phosphatase that enhances dynamin1 activity and is an important Ca2+-sensing mediator of homeostatic synaptic plasticity in neurons. Using this dynamin1xb-specific antibody, we found dynamin1xb highly enriched in synapses of all analyzed brain regions. In photoreceptor ribbon synapses, dynamin1xb was enriched in close vicinity to the synaptic ribbon in a manner indicative of a peri-active zone immunolabeling. Interestingly, in dark-adapted mice we observed an enhanced and selective enrichment of dynamin1xb in both synaptic layers of the retina in comparison to light-adapted mice. This could be due to an illumination-dependent recruitment of dynamin1xb to retinal synapses and/or due to a darkness-induced increase of dynamin1xb biosynthesis. These latter findings indicate that dynamin1xb is part of a versatile and highly adjustable, activity-regulated endocytic synaptic machinery.
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Affiliation(s)
- Marie-Lisa Eich
- Department of Neuroanatomy, Medical School Homburg/Saar, Institute for Anatomy and Cell Biology, Saarland UniversityHomburg/Saar, Germany
| | - Ekta Dembla
- Department of Neuroanatomy, Medical School Homburg/Saar, Institute for Anatomy and Cell Biology, Saarland UniversityHomburg/Saar, Germany
| | - Silke Wahl
- Department of Neuroanatomy, Medical School Homburg/Saar, Institute for Anatomy and Cell Biology, Saarland UniversityHomburg/Saar, Germany
| | - Mayur Dembla
- Department of Neuroanatomy, Medical School Homburg/Saar, Institute for Anatomy and Cell Biology, Saarland UniversityHomburg/Saar, Germany
| | - Karin Schwarz
- Department of Neuroanatomy, Medical School Homburg/Saar, Institute for Anatomy and Cell Biology, Saarland UniversityHomburg/Saar, Germany
| | - Frank Schmitz
- Department of Neuroanatomy, Medical School Homburg/Saar, Institute for Anatomy and Cell Biology, Saarland UniversityHomburg/Saar, Germany
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25
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Aggarwal A, Hitchen TL, Ootes L, McAllery S, Wong A, Nguyen K, McCluskey A, Robinson PJ, Turville SG. HIV infection is influenced by dynamin at 3 independent points in the viral life cycle. Traffic 2017; 18:392-410. [PMID: 28321960 DOI: 10.1111/tra.12481] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 03/16/2017] [Accepted: 03/16/2017] [Indexed: 12/19/2022]
Abstract
CD4 T cells are important cellular targets for HIV-1, yet the primary site of HIV fusion remains unresolved. Candidate fusion sites are either the plasma membrane or from within endosomes. One area of investigation compounding the controversy of this field, is the role of the protein dynamin in the HIV life cycle. To understand the role of dynamin in primary CD4 T cells we combined dynamin inhibition with a series of complementary assays based on single particle tracking, HIV fusion, detection of HIV DNA products and active viral transcription. We identify 3 levels of dynamin influence on the HIV life cycle. Firstly, dynamin influences productive infection by preventing cell cycle progression. Secondly, dynamin influences endocytosis rates and increases the probability of endosomal fusion. Finally, we provide evidence in resting CD4 T cells that dynamin directly regulates the HIV fusion reaction at the plasma membrane. We confirm this latter observation using 2 divergent dynamin modulating compounds, one that enhances dynamin conformations associated with dynamin ring formation (ryngo-1-23) and the other that preferentially targets dynamin conformations that appear in helices (dyngo-4a). This in-depth understanding of dynamin's roles in HIV infection clarifies recent controversies and furthermore provides evidence for dynamin regulation specifically in the HIV fusion reaction.
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Affiliation(s)
- Anupriya Aggarwal
- The Kirby Institute, University of New South Wales, New South Wales, Australia
| | - Tina L Hitchen
- The Kirby Institute, University of New South Wales, New South Wales, Australia
| | - Lars Ootes
- The Kirby Institute, University of New South Wales, New South Wales, Australia
| | - Samantha McAllery
- The Kirby Institute, University of New South Wales, New South Wales, Australia
| | - Andrew Wong
- The Kirby Institute, University of New South Wales, New South Wales, Australia
| | - Khanh Nguyen
- The Kirby Institute, University of New South Wales, New South Wales, Australia
| | - Adam McCluskey
- Centre for Chemical Biology, Chemistry, School of Environmental and Life Sciences, The University of Newcastle, Callaghan, Australia
| | - Phillip J Robinson
- Children's Medical Research Institute, The University of Sydney, New South Wales, Australia
| | - Stuart G Turville
- The Kirby Institute, University of New South Wales, New South Wales, Australia
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26
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Basagiannis D, Zografou S, Galanopoulou K, Christoforidis S. Dynasore impairs VEGFR2 signalling in an endocytosis-independent manner. Sci Rep 2017; 7:45035. [PMID: 28327657 PMCID: PMC5361198 DOI: 10.1038/srep45035] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 02/17/2017] [Indexed: 12/17/2022] Open
Abstract
VEGFR2 is a critical angiogenic receptor playing a key role in vascular homeostasis. Upon activation by VEGF, VEGFR2 becomes endocytosed. Internalisation of VEGFR2 is facilitated, in part, through clathrin mediated endocytosis (CME), the role of which in VEGFR2 function is debated. Here, we confirm the contribution of CME in VEGFR2 uptake. However, curiously, we find that different approaches of inhibition of CME exert contradictory effects on VEGF signalling; knockdown of clathrin, or of dynamin, or overexpression of dynamin K44A, do not affect VEGF-induced phosphorylation of ERK1/2, while dynasore causes strong inhibition. We resolve this discrepancy by showing that although dynasore inhibits CME of VEGFR2, its inhibitory action in ERK1/2 phosphorylation is not related to attenuation of VEGFR2 endocytosis; it is rather due to an off-target effect of the drug. Dynasore inhibits VEGF-induced calcium release, a signalling event that lies upstream of ERK1/2, which implies that this effect could be responsible, at least in part, for the inhibitory action of the drug on VEGF-to-ERK1/2 signalling. These results raise caution that although dynasore is specific in inhibiting clathrin- and dynamin-mediated endocytosis, it may also exert off-target effects on signalling molecules, hence influencing the interpretation of the role of endocytosis in signalling.
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Affiliation(s)
- Dimitris Basagiannis
- Institute of Molecular Biology and Biotechnology-Biomedical Research, Foundation for Research and Technology, 45110 Ioannina, Greece.,Laboratory of Biological Chemistry, Department of Medicine, School of Health Sciences, University of Ioannina, 45110 Ioannina, Greece
| | - Sofia Zografou
- Institute of Molecular Biology and Biotechnology-Biomedical Research, Foundation for Research and Technology, 45110 Ioannina, Greece
| | - Katerina Galanopoulou
- Institute of Molecular Biology and Biotechnology-Biomedical Research, Foundation for Research and Technology, 45110 Ioannina, Greece.,Laboratory of Biological Chemistry, Department of Medicine, School of Health Sciences, University of Ioannina, 45110 Ioannina, Greece
| | - Savvas Christoforidis
- Institute of Molecular Biology and Biotechnology-Biomedical Research, Foundation for Research and Technology, 45110 Ioannina, Greece.,Laboratory of Biological Chemistry, Department of Medicine, School of Health Sciences, University of Ioannina, 45110 Ioannina, Greece
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Müller-Deile J, Teng B, Schenk H, Haller H, Reiser J, Sever S, Schiffer M. Drugs targeting dynamin can restore cytoskeleton and focal contact alterations of urinary podocytes derived from patients with nephrotic syndrome. ANNALS OF TRANSLATIONAL MEDICINE 2016; 4:439. [PMID: 27942530 DOI: 10.21037/atm.2016.10.72] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Janina Müller-Deile
- Department of Medicine/Nephrology, Hannover Medical School, Hannover, Germany
| | - Beina Teng
- Department of Medicine/Nephrology, Hannover Medical School, Hannover, Germany
| | - Heiko Schenk
- Department of Medicine/Nephrology, Hannover Medical School, Hannover, Germany
| | - Hermann Haller
- Department of Medicine/Nephrology, Hannover Medical School, Hannover, Germany
| | - Jochen Reiser
- Department of Medicine, Harvard Medical School, Division of Nephrology, Massachusetts General Hospital, Charlestown, USA
| | - Sanja Sever
- Department of Medicine, Rush University Medical Center, Chicago, USA
| | - Mario Schiffer
- Department of Medicine/Nephrology, Hannover Medical School, Hannover, Germany
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Gu C, Lee HW, Garborcauskas G, Reiser J, Gupta V, Sever S. Dynamin Autonomously Regulates Podocyte Focal Adhesion Maturation. J Am Soc Nephrol 2016; 28:446-451. [PMID: 27432739 DOI: 10.1681/asn.2016010008] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 06/01/2016] [Indexed: 12/31/2022] Open
Abstract
Rho family GTPases, the prototypical members of which are Cdc42, Rac1, and RhoA, are molecular switches best known for regulating the actin cytoskeleton. In addition to the canonical small GTPases, the large GTPase dynamin has been implicated in regulating the actin cytoskeleton via direct dynamin-actin interactions. The physiologic role of dynamin in regulating the actin cytoskeleton has been linked to the maintenance of the kidney filtration barrier. Additionally, the small molecule Bis-T-23, which promotes actin-dependent dynamin oligomerization and thus, increases actin polymerization, improved renal health in diverse models of CKD, implicating dynamin as a potential therapeutic target for the treatment of CKD. Here, we show that treating cultured mouse podocytes with Bis-T-23 promoted stress fiber formation and focal adhesion maturation in a dynamin-dependent manner. Furthermore, Bis-T-23 induced the formation of focal adhesions and stress fibers in cells in which the RhoA signaling pathway was downregulated by multiple experimental approaches. Our study suggests that dynamin regulates focal adhesion maturation by a mechanism parallel to and synergistic with the RhoA signaling pathway. Identification of dynamin as one of the essential and autonomous regulators of focal adhesion maturation suggests a molecular mechanism that underlies the beneficial effect of Bis-T-23 on podocyte physiology.
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Affiliation(s)
- Changkyu Gu
- Department of Medicine, Harvard Medical School, Division of Nephrology, Massachusetts General Hospital, Charlestown, Massachusetts; and
| | - Ha Won Lee
- Department of Internal Medicine, Rush University Medical Center, Chicago, Illinois
| | - Garrett Garborcauskas
- Department of Medicine, Harvard Medical School, Division of Nephrology, Massachusetts General Hospital, Charlestown, Massachusetts; and
| | - Jochen Reiser
- Department of Internal Medicine, Rush University Medical Center, Chicago, Illinois
| | - Vineet Gupta
- Department of Internal Medicine, Rush University Medical Center, Chicago, Illinois
| | - Sanja Sever
- Department of Medicine, Harvard Medical School, Division of Nephrology, Massachusetts General Hospital, Charlestown, Massachusetts; and
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Yamada H, Kobayashi K, Zhang Y, Takeda T, Takei K. Expression of a dynamin 2 mutant associated with Charcot-Marie-Tooth disease leads to aberrant actin dynamics and lamellipodia formation. Neurosci Lett 2016; 628:179-85. [PMID: 27328317 DOI: 10.1016/j.neulet.2016.06.030] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2016] [Revised: 06/03/2016] [Accepted: 06/16/2016] [Indexed: 10/21/2022]
Abstract
Specific mutations in dynamin 2 are linked to Charcot-Marie-Tooth disease (CMT), an inherited peripheral neuropathy. However, the effects of these mutations on dynamin function, particularly in relation to the regulation of the actin cytoskeleton remain unclear. Here, selected CMT-associated dynamin mutants were expressed to examine their role in the pathogenesis of CMT in U2OS cells. Ectopic expression of the dynamin CMT mutants 555Δ3 and K562E caused an approximately 50% decrease in serum stimulation-dependent lamellipodia formation; however, only K562E caused aberrations in the actin cytoskeleton. Immunofluorescence analysis showed that the K562E mutation resulted in the disappearance of radially aligned actin bundles and the simultaneous appearance of F-actin clusters. Live-cell imaging analyses showed F-actin polymers of decreased length assembled into immobile clusters in K562E-expressing cells. The K562E dynamin mutant colocalized with the F-actin clusters, whereas its colocalization with clathrin-coated pit marker proteins was decreased. Essentially the same results were obtained using another cell line, HeLa and NG108-15 cells. The present study is the first to show the association of dynamin CMT mutations with aberrant actin dynamics and lamellipodia, which may contribute to defective endocytosis and myelination in Schwann cells in CMT.
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Affiliation(s)
- Hiroshi Yamada
- Department of Neuroscience, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan; CREST, Japan Science and Technology Agency, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan
| | - Kinue Kobayashi
- Department of Neuroscience, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan
| | - Yubai Zhang
- Department of Neuroscience, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan
| | - Tetsuya Takeda
- Department of Neuroscience, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan; CREST, Japan Science and Technology Agency, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan
| | - Kohji Takei
- Department of Neuroscience, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan; CREST, Japan Science and Technology Agency, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan.
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30
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In vitro model of bone to facilitate measurement of adhesion forces and super-resolution imaging of osteoclasts. Sci Rep 2016; 6:22585. [PMID: 26935172 PMCID: PMC4776281 DOI: 10.1038/srep22585] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Accepted: 02/18/2016] [Indexed: 11/08/2022] Open
Abstract
To elucidate processes in the osteoclastic bone resorption, visualise resorption and related actin reorganisation, a combination of imaging technologies and an applicable in vitro model is needed. Nanosized bone powder from matching species is deposited on any biocompatible surface in order to form a thin, translucent, smooth and elastic representation of injured bone. Osteoclasts cultured on the layer expressed matching morphology to ones cultured on sawed cortical bone slices. Resorption pits were easily identified by reflectance microscopy. The coating allowed actin structures on the bone interface to be visualised with super-resolution microscopy along with a detailed interlinked actin networks and actin branching in conjunction with V-ATPase, dynamin and Arp2/3 at actin patches. Furthermore, we measured the timescale of an adaptive osteoclast adhesion to bone by force spectroscopy experiments on live osteoclasts with bone-coated AFM cantilevers. Utilising the in vitro model and the advanced imaging technologies we localised immunofluorescence signals in respect to bone with high precision and detected resorption at its early stages. Put together, our data supports a cyclic model for resorption in human osteoclasts.
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Peters NC, Berg CA. Dynamin-mediated endocytosis is required for tube closure, cell intercalation, and biased apical expansion during epithelial tubulogenesis in the Drosophila ovary. Dev Biol 2015; 409:39-54. [PMID: 26542010 DOI: 10.1016/j.ydbio.2015.10.034] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Revised: 08/09/2015] [Accepted: 10/31/2015] [Indexed: 11/28/2022]
Abstract
Most metazoans are able to grow beyond a few hundred cells and to support differentiated tissues because they elaborate multicellular, epithelial tubes that are indispensable for nutrient and gas exchange. To identify and characterize the cellular behaviors and molecular mechanisms required for the morphogenesis of epithelial tubes (i.e., tubulogenesis), we have turned to the D. melanogaster ovary. Here, epithelia surrounding the developing egg chambers first pattern, then form and extend a set of simple, paired, epithelial tubes, the dorsal appendage (DA) tubes, and they create these structures in the absence of cell division or cell death. This genetically tractable system lets us assess the relative contributions that coordinated changes in cell shape, adhesion, orientation, and migration make to basic epithelial tubulogenesis. We find that Dynamin, a conserved regulator of endocytosis and the cytoskeleton, serves a key role in DA tubulogenesis. We demonstrate that Dynamin is required for distinct aspects of DA tubulogenesis: DA-tube closure, DA-tube-cell intercalation, and biased apical-luminal cell expansion. We provide evidence that Dynamin promotes these processes by facilitating endocytosis of cell-cell and cell-matrix adhesion complexes, and we find that precise levels and sub-cellular distribution of E-Cadherin and specific Integrin subunits impact DA tubulogenesis. Thus, our studies identify novel morphogenetic roles (i.e., tube closure and biased apical expansion), and expand upon established roles (i.e., cell intercalation and adhesion remodeling), for Dynamin in tubulogenesis.
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Affiliation(s)
- Nathaniel C Peters
- University of Washington, Molecular and Cellular Biology Program and Department of Genome Sciences, Box 355065, Seattle, WA 98195-5065, United States
| | - Celeste A Berg
- University of Washington, Molecular and Cellular Biology Program and Department of Genome Sciences, Box 355065, Seattle, WA 98195-5065, United States.
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Lee CS, Kim JM, Ghim J, Suh PG, Ryu SH. GTP-dependent interaction between phospholipase D and dynamin modulates fibronectin-induced cell spreading. Cell Signal 2015; 27:2363-70. [PMID: 26341143 DOI: 10.1016/j.cellsig.2015.08.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Accepted: 08/30/2015] [Indexed: 11/27/2022]
Abstract
Phospholipase D (PLD) is one of the key enzymes to mediate a variety of cellular phenomena including endocytosis, actin rearrangement, proliferation, differentiation, and migration. Dynamin as a PLD-interacting partner is a large GTP binding protein that has been considered a mechanochemical enzyme involved in endocytosis by hydrolyzing GTP. Although both PLD and dynamin have been implicated in the regulation of actin cytoskeleton, it is not known how they have a link to regulate fibronectin (FN)-induced cell spreading. Furthermore, it is unknown whether dynamin can work as a GTP-dependent regulator through its interaction with other proteins. Here, we demonstrate that PLD can be regulated by dynamin in a GTP-dependent manner and that this is critical for FN-mediated cell spreading. First, we verified that GTP-loaded dynamin can mediate the cell spreading by FN by using dynamin's GTP binding deficient mutant (K44A). Also, we confirmed that blocking the PLD activity inhibited FN-induced cell spreading, not cell adhesion. Moreover, PLD interacted with dynamin in a GTP-dependent manner in FN signaling, and this interaction was crucial for FN-induced PLD activation and cell spreading. Also, we found that PLD mutant (R128K) that didn't have GAP activity increased the GTP-dependent interaction between PLD and dynamin; it also increased PLD activity and cell spreading. These findings suggest that the observed increase in PLD activity was through boosting the binding of PLD with dynamin and it facilitated FN-induced cell spreading. These results imply that GTP-loaded dynamin, like a small GTPase could mediate a "switch on" signaling via interaction with PLD that has a role as an effector.
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Affiliation(s)
- Chang Sup Lee
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang 790-784, South Korea
| | - Jong Min Kim
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang 790-784, South Korea
| | - Jaewang Ghim
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang 790-784, South Korea
| | - Pann-Ghill Suh
- School of Life Science, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, South Korea
| | - Sung Ho Ryu
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang 790-784, South Korea.
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Pharmacological targeting of actin-dependent dynamin oligomerization ameliorates chronic kidney disease in diverse animal models. Nat Med 2015; 21:601-9. [PMID: 25962121 PMCID: PMC4458177 DOI: 10.1038/nm.3843] [Citation(s) in RCA: 89] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 03/18/2015] [Indexed: 12/11/2022]
Abstract
Dysregulation of the actin cytoskeleton in podocytes represents a common pathway in the pathogenesis of proteinuria across a spectrum of chronic kidney diseases (CKD). The GTPase dynamin has been implicated in the maintenance of cellular architecture in podocytes through its direct interaction with actin. Furthermore, the propensity of dynamin to oligomerize into higher-order structures in an actin-dependent manner and to crosslink actin microfilaments into higher order structures have been correlated with increased actin polymerization and global organization of the actin cytoskeleton in the cell. We found that use of the small molecule Bis-T-23, which promotes actin-dependent dynamin oligomerization and thus increased actin polymerization in injured podocytes, was sufficient to improve renal health in diverse models of both transient kidney disease and of CKD. In particular, administration of Bis-T-23 in these renal disease models restored the normal ultrastructure of podocyte foot processes, lowered proteinuria, lowered collagen IV deposits in the mesangial matrix, diminished mesangial matrix expansion and extended lifespan. These results further establish that alterations in the actin cytoskeleton of kidney podocytes is a common hallmark of CKD, while also underscoring the significant regenerative potential of injured glomeruli and that targeting the oligomerization cycle of dynamin represents an attractive potential therapeutic target to treat CKD.
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Role of dynamin in elongated cell migration in a 3D matrix. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:611-8. [DOI: 10.1016/j.bbamcr.2014.12.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Revised: 12/04/2014] [Accepted: 12/05/2014] [Indexed: 11/18/2022]
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Janus-faces of NME-oncoprotein interactions. Naunyn Schmiedebergs Arch Pharmacol 2014; 388:175-87. [PMID: 25366701 DOI: 10.1007/s00210-014-1062-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Accepted: 10/15/2014] [Indexed: 12/26/2022]
Abstract
Since the identification of Nm23 (NME1, NME/NM23 nucleoside diphosphate kinase 1) as the first non-metastatic protein, a great deal of research on members of the NME family of proteins has focused on roles in processes implicated in carcinogenesis and particularly their regulation of cellular motility and the process of metastatic spread. To date, there are ten identified members of this family of genes, and these can be dichotomized into groups both taxonomically and by the presence or absence of their nucleoside diphosphate kinase activity with NMEs 1-4 encoding nucleoside diphosphate kinases (NDPKs) and NMEs 5-9 plus RP2 displaying little if any NDPK activity. NMEs are relatively small proteins that can form hetero-oligomers (typically hexamers), and given the apparent genetic redundancy of some NMEs and the number of different isoforms, it is perhaps not surprising that there remains a great deal of uncertainty regarding their function and even more regarding cellular mechanisms of action. Since residues that contribute to NDPK activity span much of the protein, it seems likely that the consequences of NME expression must be mediated through their NDPK activity, through interactions with other structures in cells including protein-protein interactions or through combinations of these. Our goal in this review is to focus on some of the protein-protein interactions that have been identified and to highlight some of the challenges that face this area of research.
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Gu C, Chang J, Shchedrina VA, Pham VA, Hartwig JH, Suphamungmee W, Lehman W, Hyman BT, Bacskai BJ, Sever S. Regulation of dynamin oligomerization in cells: the role of dynamin-actin interactions and its GTPase activity. Traffic 2014; 15:819-38. [PMID: 24891099 DOI: 10.1111/tra.12178] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 05/26/2014] [Accepted: 05/28/2014] [Indexed: 01/22/2023]
Abstract
Dynamin is a 96-kDa protein that has multiple oligomerization states that influence its GTPase activity. A number of different dynamin effectors, including lipids, actin filaments, and SH3-domain-containing proteins, have been implicated in the regulation of dynamin oligomerization, though their roles in influencing dynamin oligomerization have been studied predominantly in vitro using recombinant proteins. Here, we identify higher order dynamin oligomers such as rings and helices in vitro and in live cells using fluorescence lifetime imaging microscopy (FLIM). FLIM detected GTP- and actin-dependent dynamin oligomerization at distinct cellular sites, including the cell membrane and transition zones where cortical actin transitions into stress fibers. Our study identifies a major role for direct dynamin-actin interactions and dynamin's GTPase activity in the regulation of dynamin oligomerization in cells.
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Affiliation(s)
- Changkyu Gu
- Division of Nephrology, Massachusetts General Hospital, Charlestown, MA, 02129, USA
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Olivares MJ, González-Jamett AM, Guerra MJ, Baez-Matus X, Haro-Acuña V, Martínez-Quiles N, Cárdenas AM. Src kinases regulate de novo actin polymerization during exocytosis in neuroendocrine chromaffin cells. PLoS One 2014; 9:e99001. [PMID: 24901433 PMCID: PMC4047038 DOI: 10.1371/journal.pone.0099001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Accepted: 05/09/2014] [Indexed: 11/19/2022] Open
Abstract
The cortical actin network is dynamically rearranged during secretory processes. Nevertheless, it is unclear how de novo actin polymerization and the disruption of the preexisting actin network control transmitter release. Here we show that in bovine adrenal chromaffin cells, both formation of new actin filaments and disruption of the preexisting cortical actin network are induced by Ca2+ concentrations that trigger exocytosis. These two processes appear to regulate different stages of exocytosis; whereas the inhibition of actin polymerization with the N-WASP inhibitor wiskostatin restricts fusion pore expansion, thus limiting the release of transmitters, the disruption of the cortical actin network with cytochalasin D increases the amount of transmitter released per event. Further, the Src kinase inhibitor PP2, and cSrc SH2 and SH3 domains also suppress Ca2+-dependent actin polymerization, and slow down fusion pore expansion without disturbing the cortical F-actin organization. Finally, the isolated SH3 domain of c-Src prevents both the disruption of the actin network and the increase in the quantal release induced by cytochalasin D. These findings support a model where a rise in the cytosolic Ca2+ triggers actin polymerization through a mechanism that involves Src kinases. The newly formed actin filaments would speed up the expansion of the initial fusion pore, whereas the preexisting actin network might control a different step of the exocytosis process.
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Affiliation(s)
- María José Olivares
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Playa Ancha, Valparaíso, Chile
| | - Arlek M. González-Jamett
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Playa Ancha, Valparaíso, Chile
| | - María José Guerra
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Playa Ancha, Valparaíso, Chile
| | - Ximena Baez-Matus
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Playa Ancha, Valparaíso, Chile
| | - Valentina Haro-Acuña
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Playa Ancha, Valparaíso, Chile
| | - Narcisa Martínez-Quiles
- Departamento de Microbiología (Inmunología), Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain
| | - Ana M. Cárdenas
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Playa Ancha, Valparaíso, Chile
- * E-mail:
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Romeu A, Arola L. Classical dynamin DNM1 and DNM3 genes attain maximum expression in the normal human central nervous system. BMC Res Notes 2014; 7:188. [PMID: 24673776 PMCID: PMC3986822 DOI: 10.1186/1756-0500-7-188] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2013] [Accepted: 03/24/2014] [Indexed: 01/01/2023] Open
Abstract
Dynamin is a super-family of large GTPase proteins that polymerise during their biological activity. Dynamin polymers form around lipid tubes and contribute to the membrane fission and scission of nascent vesicles from parent membranes. Here we used the NCBI Gene Expression Omnibus (GEO) database and the BioGPS gene expression portal to study differential dynamin gene expression in normal human organs or tissues. From the GDS1096 and GDS596 dataset, we downloaded the relative expression levels of dynamin-related genes (presented as percentages), with respect to all of the other genes on the array (platform Affymetrix GPL96), which includes the best characterised human genes. The expression profiles of dynamin in the central nervous system (CNS) are clearly distinct from the expression profiles in the other organs or tissues studied. We found that the classical dynamin DNM1 and DNM3 genes reach their maximum expression levels (100% of maximal expression) in all normal human CNS tissues studied. This is in contrast to the expression profile in the other normal human organs or tissues studied, in which both dynamin DNM1 and DNM3 genes showed approximately 50% maximal expression. This data mining analysis supports the concept that there is a relationship between the synapse and the molecular function of dynamin, suggesting a new field of work in the study of neurodegenerative diseases.
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Affiliation(s)
- Antoni Romeu
- Nutrigenomics Research Group, Department of Biochemistry and Biotechnology, Rovira i Virgili University, Tarragona, Spain.
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