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Martínez-Mármol R, Muhaisen A, Cotrufo T, Roselló-Busquets C, Ros O, Hernaiz-Llorens M, Pérez-Branguli F, Andrés RM, Parcerisas A, Pascual M, Ulloa F, Soriano E. Syntaxin-1 is necessary for UNC5A-C/Netrin-1-dependent macropinocytosis and chemorepulsion. Front Mol Neurosci 2023; 16:1253954. [PMID: 37829513 PMCID: PMC10565356 DOI: 10.3389/fnmol.2023.1253954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Accepted: 09/04/2023] [Indexed: 10/14/2023] Open
Abstract
Introduction Brain connectivity requires correct axonal guidance to drive axons to their appropriate targets. This process is orchestrated by guidance cues that exert attraction or repulsion to developing axons. However, the intricacies of the cellular machinery responsible for the correct response of growth cones are just being unveiled. Netrin-1 is a bifunctional molecule involved in axon pathfinding and cell migration that induces repulsion during postnatal cerebellar development. This process is mediated by UNC5 homolog receptors located on external granule layer (EGL) tracts. Methods Biochemical, imaging and cell biology techniques, as well as syntaxin-1A/B (Stx1A/B) knock-out mice were used in primary cultures and brain explants. Results and discussion Here, we demonstrate that this response is characterized by enhanced membrane internalization through macropinocytosis, but not clathrin-mediated endocytosis. We show that UNC5A, UNC5B, and UNC5C receptors form a protein complex with the t-SNARE syntaxin-1. By combining botulinum neurotoxins, an shRNA knock-down strategy and Stx1 knock-out mice, we demonstrate that this SNARE protein is required for Netrin1-induced macropinocytosis and chemorepulsion, suggesting that Stx1 is crucial in regulating Netrin-1-mediated axonal guidance.
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Affiliation(s)
- Ramón Martínez-Mármol
- Department of Cell Biology, Physiology and Immunology, Faculty of Biology and Institute of Neurosciences, Universitat de Barcelona (UB), Barcelona, Spain
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, Australia
| | - Ashraf Muhaisen
- Department of Cell Biology, Physiology and Immunology, Faculty of Biology and Institute of Neurosciences, Universitat de Barcelona (UB), Barcelona, Spain
- Centro de Investigación Biomédica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED-CIBER), ISCIII, Madrid, Spain
| | - Tiziana Cotrufo
- Department of Cell Biology, Physiology and Immunology, Faculty of Biology and Institute of Neurosciences, Universitat de Barcelona (UB), Barcelona, Spain
- Centro de Investigación Biomédica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED-CIBER), ISCIII, Madrid, Spain
| | - Cristina Roselló-Busquets
- Department of Cell Biology, Physiology and Immunology, Faculty of Biology and Institute of Neurosciences, Universitat de Barcelona (UB), Barcelona, Spain
| | - Oriol Ros
- Department of Cell Biology, Physiology and Immunology, Faculty of Biology and Institute of Neurosciences, Universitat de Barcelona (UB), Barcelona, Spain
| | - Marc Hernaiz-Llorens
- Department of Cell Biology, Physiology and Immunology, Faculty of Biology and Institute of Neurosciences, Universitat de Barcelona (UB), Barcelona, Spain
| | - Francesc Pérez-Branguli
- Department of Cell Biology, Physiology and Immunology, Faculty of Biology and Institute of Neurosciences, Universitat de Barcelona (UB), Barcelona, Spain
- IZKF Junior Research Group and BMBF Research Group Neuroscience, IZKF, Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Erlangen, Germany
| | - Rosa Maria Andrés
- Department of Cell Biology, Physiology and Immunology, Faculty of Biology and Institute of Neurosciences, Universitat de Barcelona (UB), Barcelona, Spain
- Centro de Investigación Biomédica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED-CIBER), ISCIII, Madrid, Spain
| | - Antoni Parcerisas
- Tissue Repair and Regeneration Laboratory (TR2Lab), Institut de Recerca i Innovació en Ciències de la Vida i de la Salut a la Catalunya Central (IRIS-CC), Vic, Spain
- Biosciences Department, Faculty of Sciences, Technology and Engineerings, University of Vic - Central University of Catalonia (UVic-UCC), Vic, Spain
| | - Marta Pascual
- Department of Cell Biology, Physiology and Immunology, Faculty of Biology and Institute of Neurosciences, Universitat de Barcelona (UB), Barcelona, Spain
- Centro de Investigación Biomédica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED-CIBER), ISCIII, Madrid, Spain
| | - Fausto Ulloa
- Department of Cell Biology, Physiology and Immunology, Faculty of Biology and Institute of Neurosciences, Universitat de Barcelona (UB), Barcelona, Spain
- Centro de Investigación Biomédica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED-CIBER), ISCIII, Madrid, Spain
| | - Eduardo Soriano
- Department of Cell Biology, Physiology and Immunology, Faculty of Biology and Institute of Neurosciences, Universitat de Barcelona (UB), Barcelona, Spain
- Centro de Investigación Biomédica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED-CIBER), ISCIII, Madrid, Spain
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Gallo A, Danglot L, Giordano F, Hewlett B, Binz T, Vannier C, Galli T. Role of the Sec22b-E-Syt complex in neurite growth and ramification. J Cell Sci 2020; 133:jcs.247148. [PMID: 32843578 DOI: 10.1242/jcs.247148] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 08/12/2020] [Indexed: 12/12/2022] Open
Abstract
Axons and dendrites are long and often ramified neurites that need particularly intense plasma membrane (PM) expansion during the development of the nervous system. Neurite growth depends on non-fusogenic Sec22b-Stx1 SNARE complexes at endoplasmic reticulum (ER)-PM contacts. Here, we show that Sec22b interacts with members of the extended synaptotagmin (E-Syt) family of ER lipid transfer proteins (LTPs), and this interaction depends on the longin domain of Sec22b. Overexpression of E-Syts stabilizes Sec22b-Stx1 association, whereas silencing of E-Syts has the opposite effect. Overexpression of wild-type E-Syt2, but not mutants unable to transfer lipids or attach to the ER, increase the formation of axonal filopodia and ramification of neurites in developing neurons. This effect is inhibited by a clostridial neurotoxin cleaving Stx1, and expression of the Sec22b longin domain and a Sec22b mutant with an extended linker between the SNARE and transmembrane domains. We conclude that Sec22b-Stx1 ER-PM contact sites contribute to PM expansion by interacting with LTPs, such as E-Syts.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Alessandra Gallo
- Université de Paris, Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM, Membrane Traffic in Healthy & Diseased Brain, F-75014 Paris, France.,Ecole des Neurosciences de Paris (ENP), F-75006 Paris, France
| | - Lydia Danglot
- Université de Paris, Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM, Membrane Traffic in Healthy & Diseased Brain, F-75014 Paris, France
| | - Francesca Giordano
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Paris-Sud University, Paris-Saclay University, Gif-sur-Yvette cedex, 91198, France
| | - Bailey Hewlett
- Université de Paris, Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM, Membrane Traffic in Healthy & Diseased Brain, F-75014 Paris, France
| | - Thomas Binz
- Medizinische Hochschule Hannover, Institut für Physiologische Chemie OE4310, 30625 Hannover, Germany
| | - Christian Vannier
- Université de Paris, Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM, Membrane Traffic in Healthy & Diseased Brain, F-75014 Paris, France
| | - Thierry Galli
- Université de Paris, Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM, Membrane Traffic in Healthy & Diseased Brain, F-75014 Paris, France .,GHU PARIS psychiatrie & neurosciences, F-75014 Paris, France
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Igarashi M, Honda A, Kawasaki A, Nozumi M. Neuronal Signaling Involved in Neuronal Polarization and Growth: Lipid Rafts and Phosphorylation. Front Mol Neurosci 2020; 13:150. [PMID: 32922262 PMCID: PMC7456915 DOI: 10.3389/fnmol.2020.00150] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 07/16/2020] [Indexed: 12/17/2022] Open
Abstract
Neuronal polarization and growth are developmental processes that occur during neuronal cell differentiation. The molecular signaling mechanisms involved in these events in in vivo mammalian brain remain unclear. Also, cellular events of the neuronal polarization process within a given neuron are thought to be constituted of many independent intracellular signal transduction pathways (the "tug-of-war" model). However, in vivo results suggest that such pathways should be cooperative with one another among a given group of neurons in a region of the brain. Lipid rafts, specific membrane domains with low fluidity, are candidates for the hotspots of such intracellular signaling. Among the signals reported to be involved in polarization, a number are thought to be present or translocated to the lipid rafts in response to extracellular signals. As part of our analysis, we discuss how such novel molecular mechanisms are combined for effective regulation of neuronal polarization and growth, focusing on the significance of the lipid rafts, including results based on recently introduced methods.
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Affiliation(s)
- Michihiro Igarashi
- Department of Neurochemistry and Molecular Cell Biology, Niigata University School of Medicine and Graduate School of Medical/Dental Sciences, Niigata, Japan
| | - Atsuko Honda
- Department of Neurochemistry and Molecular Cell Biology, Niigata University School of Medicine and Graduate School of Medical/Dental Sciences, Niigata, Japan
| | - Asami Kawasaki
- Department of Neurochemistry and Molecular Cell Biology, Niigata University School of Medicine and Graduate School of Medical/Dental Sciences, Niigata, Japan
| | - Motohiro Nozumi
- Department of Neurochemistry and Molecular Cell Biology, Niigata University School of Medicine and Graduate School of Medical/Dental Sciences, Niigata, Japan
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Urbina FL, Gupton SL. SNARE-Mediated Exocytosis in Neuronal Development. Front Mol Neurosci 2020; 13:133. [PMID: 32848598 PMCID: PMC7427632 DOI: 10.3389/fnmol.2020.00133] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 07/02/2020] [Indexed: 12/15/2022] Open
Abstract
The formation of the nervous system involves establishing complex networks of synaptic connections between proper partners. This developmental undertaking requires the rapid expansion of the plasma membrane surface area as neurons grow and polarize, extending axons through the extracellular environment. Critical to the expansion of the plasma membrane and addition of plasma membrane material is exocytic vesicle fusion, a regulated mechanism driven by soluble N-ethylmaleimide-sensitive factor attachment proteins receptors (SNAREs). Since their discovery, SNAREs have been implicated in several critical neuronal functions involving exocytic fusion in addition to synaptic transmission, including neurite initiation and outgrowth, axon specification, axon extension, and synaptogenesis. Decades of research have uncovered a rich variety of SNARE expression and function. The basis of SNARE-mediated fusion, the opening of a fusion pore, remains an enigmatic event, despite an incredible amount of research, as fusion is not only heterogeneous but also spatially small and temporally fast. Multiple modes of exocytosis have been proposed, with full-vesicle fusion (FFV) and kiss-and-run (KNR) being the best described. Whereas most in vitro work has reconstituted fusion using VAMP-2, SNAP-25, and syntaxin-1; there is much to learn regarding the behaviors of distinct SNARE complexes. In the past few years, robust heterogeneity in the kinetics and fate of the fusion pore that varies by cell type have been uncovered, suggesting a paradigm shift in how the modes of exocytosis are viewed is warranted. Here, we explore both classic and recent work uncovering the variety of SNAREs and their importance in the development of neurons, as well as historical and newly proposed modes of exocytosis, their regulation, and proteins involved in the regulation of fusion kinetics.
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Affiliation(s)
- Fabio L. Urbina
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Stephanie L. Gupton
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
- UNC Neuroscience Center, Chapel Hill, NC, United States
- UNC Lineberger Comprehensive Cancer Center, Chapel Hill, NC, United States
- Carolina Institute for Developmental Disabilities, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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Kutschenko A, Weisemann J, Kollewe K, Fiedler T, Alvermann S, Böselt S, Escher C, Garde N, Gingele S, Kaehler SB, Karatschai R, Krüger THC, Sikorra S, Tacik P, Wegner F, Wollmann J, Bigalke H, Wohlfarth K, Rummel A. Botulinum neurotoxin serotype D - A potential treatment alternative for BoNT/A and B non-responding patients. Clin Neurophysiol 2019; 130:1066-1073. [PMID: 30871800 DOI: 10.1016/j.clinph.2019.02.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 01/28/2019] [Accepted: 02/10/2019] [Indexed: 11/17/2022]
Abstract
OBJECTIVES Botulinum neurotoxin serotypes A and B (BoNT/A & B) are highly effective medicines to treat hyperactive cholinergic neurons. Due to neutralizing antibody formation, some patients may become non-responders. In these cases, the serotypes BoNT/C-G might become treatment alternatives. BoNT/D is genetically least related to BoNT/A & B and thereby circumventing neutralisation in A/B non-responders. We produced BoNT/D and compared its pharmacology with BoNT/A ex vivo in mice tissue and in vivo in human volunteers. METHODS BoNT/D was expressed recombinantly in E. coli, isolated by chromatography and its ex vivo potency was determined at mouse phrenic nerve hemidiaphragm preparations. Different doses of BoNT/D or incobotulinumtoxinA were injected into the extensor digitorum brevis (EDB) muscles (n = 30) of human volunteers. Their compound muscle action potentials were measured 11 times by electroneurography within 220 days. RESULTS Despite a 3.7-fold lower ex vivo potency in mice, a 110-fold higher dosage of BoNT/D achieved the same clinical effect as incobotulinumtoxinA while showing a 50% shortened duration of action. CONCLUSIONS BoNT/D blocks dose-dependently acetylcholine release in human motoneurons upon intramuscular administration, but its potency and duration of action is inferior to approved BoNT/A based drugs. SIGNIFICANCE BoNT/D constitutes a potential treatment alternative for BoNT/A & B non-responders.
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Affiliation(s)
- Anna Kutschenko
- Neurologische Klinik mit Klinischer Neurophysiologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Jasmin Weisemann
- Institut für Toxikologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Katja Kollewe
- Neurologische Klinik mit Klinischer Neurophysiologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Thiemo Fiedler
- Kliniken für Neurologie, Frührehabilitation und Stroke Unit, Berufsgenossenschaftliche Kliniken Bergmannstrost, Halle (Saale), Germany
| | - Sascha Alvermann
- Neurologische Klinik mit Klinischer Neurophysiologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Sebastian Böselt
- Neurologische Klinik mit Klinischer Neurophysiologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Claus Escher
- Neurologische Klinik mit Klinischer Neurophysiologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Niklas Garde
- Neurologische Klinik mit Klinischer Neurophysiologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Stefan Gingele
- Neurologische Klinik mit Klinischer Neurophysiologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Stefan-Benno Kaehler
- Kliniken für Neurologie, Frührehabilitation und Stroke Unit, Berufsgenossenschaftliche Kliniken Bergmannstrost, Halle (Saale), Germany
| | - Ralf Karatschai
- Kliniken für Neurologie, Frührehabilitation und Stroke Unit, Berufsgenossenschaftliche Kliniken Bergmannstrost, Halle (Saale), Germany
| | - Tillmann H C Krüger
- Klinik für Psychiatrie, Sozialpsychiatrie und Psychotherapie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Stefan Sikorra
- Institut für Zellbiochemie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Pawel Tacik
- Neurologische Klinik mit Klinischer Neurophysiologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Florian Wegner
- Neurologische Klinik mit Klinischer Neurophysiologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Johannes Wollmann
- Kliniken für Neurologie, Frührehabilitation und Stroke Unit, Berufsgenossenschaftliche Kliniken Bergmannstrost, Halle (Saale), Germany
| | - Hans Bigalke
- Institut für Toxikologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Kai Wohlfarth
- Kliniken für Neurologie, Frührehabilitation und Stroke Unit, Berufsgenossenschaftliche Kliniken Bergmannstrost, Halle (Saale), Germany.
| | - Andreas Rummel
- Institut für Toxikologie, Medizinische Hochschule Hannover, Hannover, Germany.
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IGARASHI M. Molecular basis of the functions of the mammalian neuronal growth cone revealed using new methods. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2019; 95:358-377. [PMID: 31406059 PMCID: PMC6766448 DOI: 10.2183/pjab.95.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 04/26/2019] [Indexed: 05/25/2023]
Abstract
The neuronal growth cone is a highly motile, specialized structure for extending neuronal processes. This structure is essential for nerve growth, axon pathfinding, and accurate synaptogenesis. Growth cones are important not only during development but also for plasticity-dependent synaptogenesis and neuronal circuit rearrangement following neural injury in the mature brain. However, the molecular details of mammalian growth cone function are poorly understood. This review examines molecular findings on the function of the growth cone as a result of the introduction of novel methods such superresolution microscopy and (phospho)proteomics. These results increase the scope of our understating of the molecular mechanisms of growth cone behavior in the mammalian brain.
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Affiliation(s)
- Michihiro IGARASHI
- Department of Neurochemistry and Molecular Cell Biology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
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7
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Vesicular movements in the growth cone. Neurochem Int 2018; 119:71-76. [DOI: 10.1016/j.neuint.2017.09.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2017] [Revised: 08/29/2017] [Accepted: 09/24/2017] [Indexed: 01/03/2023]
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Ulloa F, Cotrufo T, Ricolo D, Soriano E, Araújo SJ. SNARE complex in axonal guidance and neuroregeneration. Neural Regen Res 2018; 13:386-392. [PMID: 29623913 PMCID: PMC5900491 DOI: 10.4103/1673-5374.228710] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Through complex mechanisms that guide axons to the appropriate routes towards their targets, axonal growth and guidance lead to neuronal system formation. These mechanisms establish the synaptic circuitry necessary for the optimal performance of the nervous system in all organisms. Damage to these networks can be repaired by neuroregenerative processes which in turn can re-establish synapses between injured axons and postsynaptic terminals. Both axonal growth and guidance and the neuroregenerative response rely on correct axonal growth and growth cone responses to guidance cues as well as correct synapses with appropriate targets. With this in mind, parallels can be drawn between axonal regeneration and processes occurring during embryonic nervous system development. However, when studying parallels between axonal development and regeneration many questions still arise; mainly, how do axons grow and synapse with their targets and how do they repair their membranes, grow and orchestrate regenerative responses after injury. Major players in the cellular and molecular processes that lead to growth cone development and movement during embryonic development are the Soluble N-ethylamaleimide Sensitive Factor (NSF) Attachment Protein Receptor (SNARE) proteins, which have been shown to be involved in axonal growth and guidance. Their involvement in axonal growth, guidance and neuroregeneration is of foremost importance, due to their roles in vesicle and membrane trafficking events. Here, we review the recent literature on the involvement of SNARE proteins in axonal growth and guidance during embryonic development and neuroregeneration.
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Affiliation(s)
- Fausto Ulloa
- Department of Cell Biology, Physiology and Immunology, School of Biology, and Institute of Neurosciences, University of Barcelona, Barcelona; Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Tiziana Cotrufo
- Department of Cell Biology, Physiology and Immunology, School of Biology, and Institute of Neurosciences, University of Barcelona, Barcelona; Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Delia Ricolo
- Institut de Biologia Molecular de Barcelona (IBMB-CSIC), Parc Cientific de Barcelona; Department of Genetics, Microbiology and Statistics, School of Biology, University of Barcelona, Barcelona, Spain
| | - Eduardo Soriano
- Department of Cell Biology, Physiology and Immunology, School of Biology, and Institute of Neurosciences, University of Barcelona, Barcelona; Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III (ISCIII), Madrid; Vall d´Hebron Institut de Recerca (VHIR), Barcelona, Spain
| | - Sofia J Araújo
- Institut de Biologia Molecular de Barcelona (IBMB-CSIC), Parc Cientific de Barcelona; Department of Genetics, Microbiology and Statistics, School of Biology, University of Barcelona, Barcelona, Spain
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Nozumi M, Nakatsu F, Katoh K, Igarashi M. Coordinated Movement of Vesicles and Actin Bundles during Nerve Growth Revealed by Superresolution Microscopy. Cell Rep 2017; 18:2203-2216. [DOI: 10.1016/j.celrep.2017.02.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 12/29/2016] [Accepted: 01/31/2017] [Indexed: 01/01/2023] Open
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Soo Hoo L, Banna CD, Radeke CM, Sharma N, Albertolle ME, Low SH, Weimbs T, Vandenberg CA. The SNARE Protein Syntaxin 3 Confers Specificity for Polarized Axonal Trafficking in Neurons. PLoS One 2016; 11:e0163671. [PMID: 27662481 PMCID: PMC5035089 DOI: 10.1371/journal.pone.0163671] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 09/12/2016] [Indexed: 11/19/2022] Open
Abstract
Cell polarity and precise subcellular protein localization are pivotal to neuronal function. The SNARE machinery underlies intracellular membrane fusion events, but its role in neuronal polarity and selective protein targeting remain unclear. Here we report that syntaxin 3 is involved in orchestrating polarized trafficking in cultured rat hippocampal neurons. We show that syntaxin 3 localizes to the axonal plasma membrane, particularly to axonal tips, whereas syntaxin 4 localizes to the somatodendritic plasma membrane. Disruption of a conserved N-terminal targeting motif, which causes mislocalization of syntaxin 3, results in coincident mistargeting of the axonal cargos neuron-glia cell adhesion molecule (NgCAM) and neurexin, but not transferrin receptor, a somatodendritic cargo. Similarly, RNAi-mediated knockdown of endogenous syntaxin 3 leads to partial mistargeting of NgCAM, demonstrating that syntaxin 3 plays an important role in its targeting. Additionally, overexpression of syntaxin 3 results in increased axonal growth. Our findings suggest an important role for syntaxin 3 in maintaining neuronal polarity and in the critical task of selective trafficking of membrane protein to axons.
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Affiliation(s)
- Linda Soo Hoo
- Department of Molecular, Cellular, and Developmental Biology, University of California Santa Barbara, Santa Barbara, California, United States of America
- Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, California, United States of America
| | - Chris D. Banna
- Department of Molecular, Cellular, and Developmental Biology, University of California Santa Barbara, Santa Barbara, California, United States of America
- Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, California, United States of America
| | - Carolyn M. Radeke
- Department of Molecular, Cellular, and Developmental Biology, University of California Santa Barbara, Santa Barbara, California, United States of America
- Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, California, United States of America
| | - Nikunj Sharma
- Department of Molecular, Cellular, and Developmental Biology, University of California Santa Barbara, Santa Barbara, California, United States of America
- Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, California, United States of America
| | - Mary E. Albertolle
- Department of Molecular, Cellular, and Developmental Biology, University of California Santa Barbara, Santa Barbara, California, United States of America
- Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, California, United States of America
| | - Seng Hui Low
- Department of Molecular, Cellular, and Developmental Biology, University of California Santa Barbara, Santa Barbara, California, United States of America
- Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, California, United States of America
| | - Thomas Weimbs
- Department of Molecular, Cellular, and Developmental Biology, University of California Santa Barbara, Santa Barbara, California, United States of America
- Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, California, United States of America
| | - Carol A. Vandenberg
- Department of Molecular, Cellular, and Developmental Biology, University of California Santa Barbara, Santa Barbara, California, United States of America
- Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, California, United States of America
- * E-mail:
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Yamashita S, Chiyonobu T, Yoshida M, Maeda H, Zuiki M, Kidowaki S, Isoda K, Morimoto M, Kato M, Saitsu H, Matsumoto N, Nakahata T, Saito MK, Hosoi H. Mislocalization of syntaxin-1 and impaired neurite growth observed in a human iPSC model for STXBP1-related epileptic encephalopathy. Epilepsia 2016; 57:e81-6. [PMID: 26918652 DOI: 10.1111/epi.13338] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/21/2016] [Indexed: 11/29/2022]
Abstract
Syntaxin-binding protein 1 (STXBP1) is essential for synaptic vesicle exocytosis. Mutations of its encoding gene, STXBP1, are among the most frequent genetic causes of epileptic encephalopathies. However, the precise pathophysiology of STXBP1 haploinsufficiency has not been elucidated. Using patient-derived induced pluripotent stem cells (iPSCs), we aimed to establish a neuronal model for STXBP1 haploinsufficiency and determine the pathophysiologic basis for STXBP1 encephalopathy. We generated iPSC lines from a patient with Ohtahara syndrome (OS) harboring a heterozygous nonsense mutation of STXBP1 (c.1099C>T; p.R367X) and performed neuronal differentiation. Both STXBP1 messenger RNA (mRNA) and STXBP1 protein expression levels of OS-derived neurons were approximately 50% lower than that of control-derived neurons, suggesting that OS-derived neurons are a suitable model for elucidating the pathophysiology of STXBP1 haploinsufficiency. Through Western blot and immunocytochemistry assays, we found that OS-derived neurons show reduced levels and mislocalization of syntaxin-1, a component of soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) proteins. In addition, OS-derived neurons have impaired neurite outgrowth. In conclusion, this model enables us to investigate the neurobiology of STXBP1 encephalopathy throughout the stages of neurodevelopment. Reduced expression of STXBP1 leads to changes in the expression and localization of syntaxin-1 that may contribute to the devastating phenotype of STXBP1 encephalopathy.
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Affiliation(s)
- Satoshi Yamashita
- Department of Pediatrics, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Tomohiro Chiyonobu
- Department of Pediatrics, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Michiko Yoshida
- Department of Pediatrics, Kyoto Prefectural University of Medicine, Kyoto, Japan.,Department of Clinical Application, Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, Japan
| | - Hiroshi Maeda
- Department of Pediatrics, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Masashi Zuiki
- Department of Pediatrics, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Satoshi Kidowaki
- Department of Pediatrics, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Kenichi Isoda
- Department of Pediatrics, Kyoto Prefectural University of Medicine, Kyoto, Japan.,Department of Clinical Application, Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, Japan
| | - Masafumi Morimoto
- Department of Pediatrics, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Mitsuhiro Kato
- Department of Pediatrics, Yamagata University Faculty of Medicine, Yamagata, Japan
| | - Hirotomo Saitsu
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - Naomichi Matsumoto
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - Tatsutoshi Nakahata
- Department of Clinical Application, Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, Japan
| | - Megumu K Saito
- Department of Clinical Application, Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, Japan
| | - Hajime Hosoi
- Department of Pediatrics, Kyoto Prefectural University of Medicine, Kyoto, Japan
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12
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McGorum BC, Scholes S, Milne EM, Eaton SL, Wishart TM, Poxton IR, Moss S, Wernery U, Davey T, Harris JB, Pirie RS. Equine grass sickness, but not botulism, causes autonomic and enteric neurodegeneration and increases soluble N-ethylmaleimide-sensitive factor attachment receptor protein expression within neuronal perikarya. Equine Vet J 2016; 48:786-791. [PMID: 26640078 DOI: 10.1111/evj.12543] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 11/24/2015] [Indexed: 11/27/2022]
Abstract
REASONS FOR PERFORMING STUDY Equine grass sickness (EGS) is of unknown aetiology. Despite some evidence suggesting that it represents a toxico-infection with Clostridium botulinum types C and/or D, the effect of EGS on the functional targets of botulinum neurotoxins, namely the soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) proteins, is unknown. Further, while it is commonly stated that, unlike EGS, equine botulism is not associated with autonomic and enteric neurodegeneration, this has not been definitively assessed. OBJECTIVES To determine: 1) whether botulism causes autonomic and enteric neurodegeneration; and 2) the effect of EGS on the expression of SNARE proteins within cranial cervical ganglion (CCG) and enteric neuronal perikarya. STUDY DESIGN Descriptive study. METHODS Light microscopy was used to compare the morphology of neurons in haematoxylin-eosin stained sections of CCG and ileum from 6 EGS horses, 5 botulism horses and 6 control horses. Immunohistochemistry was used to compare the expression of synaptosomal-associated protein-25, synaptobrevin (Syb) and syntaxin within CCG neurons, and of Syb in enteric neurons, from horses with EGS, horses with botulism and control horses. The concentrations of these SNARE proteins in extracts of CCG from EGS and control horses were compared using quantitative fluorescent western blotting. RESULTS EGS, but not botulism, was associated with autonomic and enteric neurodegeneration and with increased immunoreactivity for SNARE proteins within neuronal perikarya. Quantitative fluorescent western blotting confirmed increased concentrations of synaptosomal-associated protein-25, Syb and syntaxin within CCG extracts from EGS vs. control horses, with the increases in the latter 2 proteins being statistically significant. CONCLUSIONS The occurrence of autonomic and enteric neurodegeneration, and increased expression of SNARE proteins within neuronal perikarya, in EGS but not botulism, suggests that EGS may not be caused by botulinum neurotoxins. Further investigation of the aetiology of EGS is therefore warranted.
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Affiliation(s)
- B C McGorum
- Royal (Dick) School of Veterinary Studies and The Roslin Institute, University of Edinburgh, Roslin, UK.
| | - S Scholes
- SAC Consulting Veterinary Services, Penicuik, Midlothian, UK
| | - E M Milne
- Royal (Dick) School of Veterinary Studies and The Roslin Institute, University of Edinburgh, Roslin, UK
| | - S L Eaton
- Royal (Dick) School of Veterinary Studies and The Roslin Institute, University of Edinburgh, Roslin, UK
| | - T M Wishart
- Royal (Dick) School of Veterinary Studies and The Roslin Institute, University of Edinburgh, Roslin, UK.,Euan MacDonald Centre for Motor Neuron Disease Research, University of Edinburgh, Midlothian, UK
| | - I R Poxton
- Edinburgh Infectious Diseases, University of Edinburgh, Midlothian, UK
| | - S Moss
- Royal (Dick) School of Veterinary Studies and The Roslin Institute, University of Edinburgh, Roslin, UK
| | - U Wernery
- Central Veterinary Research Laboratory, Dubai, United Arab Emirates
| | - T Davey
- Electron Microscopy Research Services, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - J B Harris
- Medical Toxicology Centre and Institute of Neuroscience, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - R S Pirie
- Royal (Dick) School of Veterinary Studies and The Roslin Institute, University of Edinburgh, Roslin, UK
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13
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Membrane Trafficking in Neuronal Development: Ins and Outs of Neural Connectivity. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2016; 322:247-80. [PMID: 26940520 DOI: 10.1016/bs.ircmb.2015.10.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
During development, neurons progress through rapid yet stereotypical shape changes to achieve proper neuronal connectivity. This morphological progression requires carefully orchestrated plasma membrane expansion, insertion of membrane components including receptors for extracellular cues into the plasma membrane and removal and trafficking of membrane materials and proteins to specific locations. This review outlines the cellular machinery of membrane trafficking that play an integral role in neuronal cell shape change and function from initial neurite formation to pathway navigation and synaptogenesis.
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14
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Peng Y, Lee J, Rowland K, Wen Y, Hua H, Carlson N, Lavania S, Parrish JZ, Kim MD. Regulation of dendrite growth and maintenance by exocytosis. J Cell Sci 2015; 128:4279-92. [PMID: 26483382 DOI: 10.1242/jcs.174771] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 10/08/2015] [Indexed: 01/07/2023] Open
Abstract
Dendrites lengthen by several orders of magnitude during neuronal development, but how membrane is allocated in dendrites to facilitate this growth remains unclear. Here, we report that Ras opposite (Rop), the Drosophila ortholog of the key exocytosis regulator Munc18-1 (also known as STXBP1), is an essential factor mediating dendrite growth. Neurons with depleted Rop function exhibit reduced terminal dendrite outgrowth followed by primary dendrite degeneration, suggestive of differential requirements for exocytosis in the growth and maintenance of different dendritic compartments. Rop promotes dendrite growth together with the exocyst, an octameric protein complex involved in tethering vesicles to the plasma membrane, with Rop-exocyst complexes and exocytosis predominating in primary dendrites over terminal dendrites. By contrast, membrane-associated proteins readily diffuse from primary dendrites into terminals, but not in the reverse direction, suggesting that diffusion, rather than targeted exocytosis, supplies membranous material for terminal dendritic growth, revealing key differences in the distribution of materials to these expanding dendritic compartments.
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Affiliation(s)
- Yun Peng
- Department of Biology, University of Washington, Seattle, WA 98195, USA
| | - Jiae Lee
- Department of Biology, University of Washington, Seattle, WA 98195, USA
| | - Kimberly Rowland
- Department of Molecular and Cellular Pharmacology, University of Miami, Miller School of Medicine, Miami, FL 33136, USA
| | - Yuhui Wen
- Department of Molecular and Cellular Pharmacology, University of Miami, Miller School of Medicine, Miami, FL 33136, USA
| | - Hope Hua
- Department of Molecular and Cellular Pharmacology, University of Miami, Miller School of Medicine, Miami, FL 33136, USA
| | - Nicole Carlson
- Department of Molecular and Cellular Pharmacology, University of Miami, Miller School of Medicine, Miami, FL 33136, USA
| | - Shweta Lavania
- Department of Molecular and Cellular Pharmacology, University of Miami, Miller School of Medicine, Miami, FL 33136, USA
| | - Jay Z Parrish
- Department of Biology, University of Washington, Seattle, WA 98195, USA
| | - Michael D Kim
- Department of Molecular and Cellular Pharmacology, University of Miami, Miller School of Medicine, Miami, FL 33136, USA
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15
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Rummel A. The long journey of botulinum neurotoxins into the synapse. Toxicon 2015; 107:9-24. [PMID: 26363288 DOI: 10.1016/j.toxicon.2015.09.009] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 08/27/2015] [Accepted: 09/08/2015] [Indexed: 01/09/2023]
Abstract
Botulinum neurotoxins (BoNT) cause the disease botulism, a flaccid paralysis of the muscle. They are also very effective, widely used medicines applied locally in sub-nanogram quantities. BoNTs are released together with several non-toxic, associated proteins as progenitor toxin complexes (PCT) by Clostridium botulinum to become highly potent oral poisons ingested via contaminated food. They block the neurotransmission in susceptible animals and humans already in nanogram quantities due to their specific ability to enter motoneurons and to cleave only selected neuronal proteins involved in neuroexocytosis. BoNTs have developed a sophisticated strategy to passage the gastrointestinal tract and to be absorbed in the intestine of the host to finally attack neurons. A non-toxic non-hemagglutinin (NTNHA) forms a binary complex with BoNT to protect it from gastrointestinal degradation. This binary M-PTC is one component of the bi-modular 14-subunit ∼760 kDa large progenitor toxin complex. The other component is the structurally and functionally independent dodecameric hemagglutinin (HA) complex which facilitates the absorption on the intestinal epithelium by glycan binding. Subsequent to its transcytosis the HA complex disrupts the tight junction of the intestinal barrier from the basolateral side by binding to E-cadherin. Now, the L-PTC can also enter the circulation by paracellular routes in much larger quantities. From here, the dissociated BoNTs reach the neuromuscular junction and accumulate via interaction with polysialo gangliosides, complex glycolipids, on motoneurons at the neuromuscular junction. Subsequently, additional specific binding to luminal segments of synaptic vesicles proteins like SV2 and synaptotagmin leads to their uptake. Finally, the neurotoxins shut down the synaptic vesicle cycle, which they had exploited before to enter their target cells, via specific cleavage of soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins, which constitute the core components of the cellular membrane fusion machinery.
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Affiliation(s)
- Andreas Rummel
- Institut für Toxikologie, Medizinische Hochschule Hannover, 30623 Hannover, Germany.
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16
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Abstract
Axonal guidance and synaptic specification depends on specific signaling mechanisms that occur in growth cones. While several signaling pathways implicated in cone navigation have been identified, membrane dynamics in growth cones remains largely unknown. We took advantage of SynaptopHluorin and high-speed optical recordings to monitor the patterns of membrane dynamics in rat hippocampal growth cones. We show that exocytosis occurs both at the peripheral and central domains, including filopodia, and that SynaptopHluorin signals occur as spontaneous patterned peaks. Such transients average approximately two per minute and last ∼30 s. We also demonstrate that the chemoattractant Netrin-1 elicits increases in the frequency and slopes of these transients, with peaks averaging up to six per minute in the peripheral domain. Netrin-1-dependent regulation of exocytotic events requires the activation of the Erk1/2 and SFK pathways. Furthermore, we show that domains with high SynaptopHluorin signals correlate with high local calcium concentrations and that local, spontaneous calcium increases are associated with higher SynaptopHluorin signals. These findings demonstrate highly stereotyped, spontaneous transients of local exocytosis in growth cones and that these transients are positively regulated by chemoattractant molecules such as Netrin-1.
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17
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Tojima T, Kamiguchi H. Exocytic and endocytic membrane trafficking in axon development. Dev Growth Differ 2015; 57:291-304. [DOI: 10.1111/dgd.12218] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2015] [Revised: 04/09/2015] [Accepted: 04/09/2015] [Indexed: 12/14/2022]
Affiliation(s)
- Takuro Tojima
- Laboratory for Neuronal Growth Mechanisms; RIKEN Brain Science Institute; 2-1 Hirosawa Wako Saitama 351-0198 Japan
| | - Hiroyuki Kamiguchi
- Laboratory for Neuronal Growth Mechanisms; RIKEN Brain Science Institute; 2-1 Hirosawa Wako Saitama 351-0198 Japan
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18
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Igarashi M. Proteomic identification of the molecular basis of mammalian CNS growth cones. Neurosci Res 2014; 88:1-15. [PMID: 25066522 DOI: 10.1016/j.neures.2014.07.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Revised: 06/13/2014] [Accepted: 07/02/2014] [Indexed: 11/28/2022]
Abstract
The growth cone, which is a unique structure with high motility that forms at the tips of extending axons and dendrites, is crucial to neuronal network formation. Axonal growth of the mammalian CNS is most likely achieved by the complicated coordination of cytoskeletal rearrangement and vesicular trafficking via many proteins. Before recent advances, no methods to identify numerous proteins existed; however, proteomics revolutionarily resolved such problems. In this review, I summarize the profiles of the mammalian growth cone proteins revealed by proteomics as the molecular basis of the growth cone functions, with molecular mapping. These results should be used as a basis for understanding the mechanisms of the complex mammalian CNS developmental process.
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Affiliation(s)
- Michihiro Igarashi
- Department of Neurochemistry and Molecular Cell Biology, Niigata University Graduate School of Medical and Dental Sciences, Niigata 951-8510, Japan; Trans-disciplinary Program, Niigata University Graduate School of Medical and Dental Sciences, Niigata 951-8510, Japan.
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19
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Lawrence GW, Wang J, Brin MF, Aoki KR, Wheeler L, Dolly JO. Fusion of Golgi-derived vesicles mediated by SNAP-25 is essential for sympathetic neuron outgrowth but relatively insensitive to botulinum neurotoxins in vitro. FEBS J 2014; 281:3243-60. [PMID: 24863955 DOI: 10.1111/febs.12858] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 03/28/2014] [Accepted: 05/21/2014] [Indexed: 01/12/2023]
Abstract
Sympathetic neurons ramify to innervate multiple cells in target tissues. In compartmentalized cultures of rat superior cervical ganglion neurons, cleavage of synaptosomal-associated protein of Mr = 25 000 (SNAP-25) in neurites exposed to botulinum neurotoxin type A (BoNT/A) arrested their growth and collapsed interstitial branches, but this required large, nonclinical doses. A protease-inactive mutant proved ineffective, confirming involvement of SNAP-25 in neurite extension and arborization. BoNT/C1 acted like BoNT/A, but BoNT/E caused only mild inhibition, likely due to transient SNAP-25 proteolysis. Near-total lack of susceptibility to BoNT/B or BoNT/D revealed that vesicle-associated membrane protein (VAMPs) isoforms 1-3 are not essential. Neurite length was not reduced when either BoNT/A or BoNT/C1 was applied to the somata, with no detrimental effect on neuron viability being observed. Treatments that protect cells from deprivation of nerve growth factor failed to prevent the toxin-induced loss of neurites. Inactivation of SNAP-25 caused the accumulation at neurite branch sites of Golgi-derived organelles labelled with N-(4,4-difluoro-5,7-dimethyl-4-bora-3a,4a-diaza-s-indacene-3-pentanoyl)-sphingosine conjugated to bovine serum albumin, prior to the collapse of arbors. Notably, neurite growth was ~ 1000-fold less susceptible to BoNT/A than cholinergic transmission in these neurons. Accordingly, a BoNT/A acceptor synaptic vesicle protein 2 (SV2) was found to be colocalized with VAMP 1-3, but not with VAMP 7, which is implicated in the growth of neurites. In conclusion, neurites depend on SNAP-25 for extension but this is quite resistant to BoNT/A, possibly, because of a low density of SV2 at growth sites that are distant from the highly susceptible regions of neurotransmitter release.
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Affiliation(s)
- Gary W Lawrence
- International Centre for Neurotherapeutics, Dublin City University, Ireland
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20
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Kofuji T, Fujiwara T, Sanada M, Mishima T, Akagawa K. HPC-1/syntaxin 1A and syntaxin 1B play distinct roles in neuronal survival. J Neurochem 2014; 130:514-25. [DOI: 10.1111/jnc.12722] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Revised: 03/23/2014] [Accepted: 03/24/2014] [Indexed: 01/06/2023]
Affiliation(s)
- Takefumi Kofuji
- Radioisotope Laboratory; Kyorin University School of Medicine; Mitaka Tokyo Japan
| | - Tomonori Fujiwara
- Department of Cell Physiology; Kyorin University School of Medicine; Mitaka Tokyo Japan
| | - Masumi Sanada
- Department of Cell Physiology; Kyorin University School of Medicine; Mitaka Tokyo Japan
| | - Tatsuya Mishima
- Department of Cell Physiology; Kyorin University School of Medicine; Mitaka Tokyo Japan
| | - Kimio Akagawa
- Department of Cell Physiology; Kyorin University School of Medicine; Mitaka Tokyo Japan
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21
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MARCKS regulates membrane targeting of Rab10 vesicles to promote axon development. Cell Res 2014; 24:576-94. [PMID: 24662485 DOI: 10.1038/cr.2014.33] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 12/31/2013] [Accepted: 02/25/2014] [Indexed: 01/19/2023] Open
Abstract
Axon development requires membrane addition from the intracellular supply, which has been shown to be mediated by Rab10-positive plasmalemmal precursor vesicles (PPVs). However, the molecular mechanisms underlying the membrane trafficking processes of PPVs remain unclear. Here, we show that myristoylated alanine-rich C-kinase substrate (MARCKS) mediates membrane targeting of Rab10-positive PPVs, and this regulation is critical for axon development. We found that the GTP-locked active form of Rab10 binds to membrane-associated MARCKS, whose affinity depends on the phosphorylation status of the MARCKS effector domain. Either genetic silencing of MARCKS or disruption of its interaction with Rab10 inhibited axon growth of cortical neurons, impaired docking and fusion of Rab10 vesicles with the plasma membrane, and consequently caused a loss of membrane insertion of axonal receptors responsive to extracellular axon growth factors. Thus, this study has identified a novel function of MARCKS in mediating membrane targeting of PPVs during axon development.
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22
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Fujita A, Koinuma S, Yasuda S, Nagai H, Kamiguchi H, Wada N, Nakamura T. GTP hydrolysis of TC10 promotes neurite outgrowth through exocytic fusion of Rab11- and L1-containing vesicles by releasing exocyst component Exo70. PLoS One 2013; 8:e79689. [PMID: 24223996 PMCID: PMC3817099 DOI: 10.1371/journal.pone.0079689] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2013] [Accepted: 09/23/2013] [Indexed: 11/24/2022] Open
Abstract
The use of exocytosis for membrane expansion at nerve growth cones is critical for neurite outgrowth. TC10 is a Rho family GTPase that is essential for specific types of vesicular trafficking to the plasma membrane. Recent studies have shown that TC10 and its effector Exo70, a component of the exocyst tethering complex, contribute to neurite outgrowth. However, the molecular mechanisms of the neuritogenesis-promoting functions of TC10 remain to be established. Here, we propose that GTP hydrolysis of vesicular TC10 near the plasma membrane promotes neurite outgrowth by accelerating vesicle fusion by releasing Exo70. Using Förster resonance energy transfer (FRET)-based biosensors, we show that TC10 activity at the plasma membrane decreased at extending growth cones in hippocampal neurons and nerve growth factor (NGF)-treated PC12 cells. In neuronal cells, TC10 activity at vesicles was higher than its activity at the plasma membrane, and TC10-positive vesicles were found to fuse to the plasma membrane in NGF-treated PC12 cells. Therefore, activity of TC10 at vesicles is presumed to be inactivated near the plasma membrane during neuronal exocytosis. Our model is supported by functional evidence that constitutively active TC10 could not rescue decrease in NGF-induced neurite outgrowth induced by TC10 depletion. Furthermore, TC10 knockdown experiments and colocalization analyses confirmed the involvement of Exo70 in TC10-mediated trafficking in neuronal cells. TC10 frequently resided on vesicles containing Rab11, which is a key regulator of recycling pathways and implicated in neurite outgrowth. In growth cones, most of the vesicles containing the cell adhesion molecule L1 had TC10. Exocytosis of Rab11- and L1-positive vesicles may play a central role in TC10-mediated neurite outgrowth. The combination of this study and our previous work on the role of TC10 in EGF-induced exocytosis in HeLa cells suggests that the signaling machinery containing TC10 proposed here may be broadly used for exocytosis.
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Affiliation(s)
- Akane Fujita
- Division of Biosignaling, Research Institute for Biomedical Sciences, Tokyo University of Science, Noda, Chiba, Japan
| | - Shingo Koinuma
- Division of Biosignaling, Research Institute for Biomedical Sciences, Tokyo University of Science, Noda, Chiba, Japan
| | - Sayaka Yasuda
- Division of Biosignaling, Research Institute for Biomedical Sciences, Tokyo University of Science, Noda, Chiba, Japan
| | - Hiroyuki Nagai
- Division of Biosignaling, Research Institute for Biomedical Sciences, Tokyo University of Science, Noda, Chiba, Japan
| | - Hiroyuki Kamiguchi
- Laboratory for Neuronal Growth Mechanism, RIKEN Brain Science Institute, Wako, Saitama, Japan
| | - Naoyuki Wada
- Department of Applied Biological Science, Tokyo University of Science, Noda, Chiba, Japan
| | - Takeshi Nakamura
- Division of Biosignaling, Research Institute for Biomedical Sciences, Tokyo University of Science, Noda, Chiba, Japan
- * E-mail:
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23
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Cyclic AMP promotes axon regeneration, lesion repair and neuronal survival in lampreys after spinal cord injury. Exp Neurol 2013; 250:31-42. [PMID: 24041988 DOI: 10.1016/j.expneurol.2013.09.004] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Revised: 09/03/2013] [Accepted: 09/08/2013] [Indexed: 01/10/2023]
Abstract
Axon regeneration after spinal cord injury in mammals is inadequate to restore function, illustrating the need to design better strategies for improving outcomes. Increasing the levels of the second messenger cyclic adenosine monophosphate (cAMP) after spinal cord injury enhances axon regeneration across a wide variety of species, making it an excellent candidate molecule that has therapeutic potential. However, several important aspects of the cellular and molecular mechanisms by which cAMP enhances axon regeneration are still unclear, such as how cAMP affects axon growth patterns, the molecular components within growing axon tips, the lesion scar, and neuronal survival. To address these points, we took advantage of the large, identified reticulospinal (RS) neurons in lamprey, a vertebrate that exhibits robust axon regeneration after a complete spinal cord transection. Application of a cAMP analog, db-cAMP, at the time of spinal cord transection increased the number of axons that regenerated across the lesion site. Db-cAMP also promoted axons to regenerate in straighter paths, prevented abnormal axonal growth patterns, increased the levels of synaptotagmin within axon tips, and increased the number of axotomized neurons that survived after spinal cord injury, thereby increasing the pool of neurons available for regeneration. There was also a transient increase in the number of microglia/macrophages and improved repair of the lesion site. Taken together, these data reveal several new features of the cellular and molecular mechanisms underlying cAMP-mediated enhancement of axon regeneration, further emphasizing the positive roles for this conserved pathway.
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24
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Peng L, Liu H, Ruan H, Tepp WH, Stoothoff WH, Brown RH, Johnson EA, Yao WD, Zhang SC, Dong M. Cytotoxicity of botulinum neurotoxins reveals a direct role of syntaxin 1 and SNAP-25 in neuron survival. Nat Commun 2013; 4:1472. [PMID: 23403573 PMCID: PMC4052923 DOI: 10.1038/ncomms2462] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2012] [Accepted: 01/09/2013] [Indexed: 12/05/2022] Open
Abstract
Botulinum neurotoxins (BoNT/A-G) are well-known to act by blocking synaptic vesicle exocytosis. Whether BoNTs disrupt additional neuronal functions has not been addressed. Here we report that cleavage of syntaxin 1 (Syx 1) by BoNT/C and cleavage of SNAP-25 by BoNT/E both induce degeneration of cultured rodent and human neurons. Furthermore, although SNAP-25 cleaved by BoNT/A can still support neuron survival, it has reduced capacity to tolerate additional mutations and also fails to pair with syntaxin isoforms other than Syx 1. Syx 1 and SNAP-25 are well-known for mediating synaptic vesicle exocytosis, but we found that neuronal death is due to blockage of plasma membrane recycling processes that share Syx 1/SNAP-25 for exocytosis, independent of blockage of synaptic vesicle exocytosis. These findings reveal neuronal cytotoxicity for a subset of BoNTs and directly link Syx 1/SNAP-25 to neuron survival as the prevalent SNARE proteins mediating multiple fusion events on neuronal plasma membranes.
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Affiliation(s)
- Lisheng Peng
- Department of Microbiology and Immunobiology, Harvard Medical School, Division of Neuroscience, New England Primate Research Center, Southborough, Massachusetts 01772, USA
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25
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Phosphatidylinositol 4-phosphate 5-kinase β regulates growth cone morphology and Semaphorin 3A-triggered growth cone collapse in mouse dorsal root ganglion neurons. Neurosci Lett 2013; 547:59-64. [DOI: 10.1016/j.neulet.2013.04.062] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Revised: 04/09/2013] [Accepted: 04/30/2013] [Indexed: 11/17/2022]
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26
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Wei C, Thatcher EJ, Olena AF, Cha DJ, Perdigoto AL, Marshall AF, Carter BD, Broadie K, Patton JG. miR-153 regulates SNAP-25, synaptic transmission, and neuronal development. PLoS One 2013; 8:e57080. [PMID: 23451149 PMCID: PMC3581580 DOI: 10.1371/journal.pone.0057080] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2012] [Accepted: 01/16/2013] [Indexed: 01/01/2023] Open
Abstract
SNAP-25 is a core component of the trimeric SNARE complex mediating vesicle exocytosis during membrane addition for neuronal growth, neuropeptide/growth factor secretion, and neurotransmitter release during synaptic transmission. Here, we report a novel microRNA mechanism of SNAP-25 regulation controlling motor neuron development, neurosecretion, synaptic activity, and movement in zebrafish. Loss of miR-153 causes overexpression of SNAP-25 and consequent hyperactive movement in early zebrafish embryos. Conversely, overexpression of miR-153 causes SNAP-25 down regulation resulting in near complete paralysis, mimicking the effects of treatment with Botulinum neurotoxin. miR-153-dependent changes in synaptic activity at the neuromuscular junction are consistent with the observed movement defects. Underlying the movement defects, perturbation of miR-153 function causes dramatic developmental changes in motor neuron patterning and branching. Together, our results indicate that precise control of SNAP-25 expression by miR-153 is critically important for proper neuronal patterning as well as neurotransmission.
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Affiliation(s)
- Chunyao Wei
- Department of Biological Sciences, Vanderbilt University and Medical School, Nashville, Tennessee, United States of America
| | - Elizabeth J. Thatcher
- Department of Biological Sciences, Vanderbilt University and Medical School, Nashville, Tennessee, United States of America
| | - Abigail F. Olena
- Department of Biological Sciences, Vanderbilt University and Medical School, Nashville, Tennessee, United States of America
| | - Diana J. Cha
- Department of Biological Sciences, Vanderbilt University and Medical School, Nashville, Tennessee, United States of America
| | - Ana L. Perdigoto
- Department of Biochemistry, Vanderbilt University and Medical School, Nashville, Tennessee, United States of America
| | - Andrew F. Marshall
- Department of Biological Sciences, Vanderbilt University and Medical School, Nashville, Tennessee, United States of America
| | - Bruce D. Carter
- Department of Biochemistry, Vanderbilt University and Medical School, Nashville, Tennessee, United States of America
| | - Kendal Broadie
- Department of Biological Sciences, Vanderbilt University and Medical School, Nashville, Tennessee, United States of America
| | - James G. Patton
- Department of Biological Sciences, Vanderbilt University and Medical School, Nashville, Tennessee, United States of America
- * E-mail:
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Rab33a mediates anterograde vesicular transport for membrane exocytosis and axon outgrowth. J Neurosci 2012; 32:12712-25. [PMID: 22972995 DOI: 10.1523/jneurosci.0989-12.2012] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Axon outgrowth requires plasma membrane expansion, which results from post-Golgi vesicular transport and fusion. However, the molecular mechanisms regulating post-Golgi vesicular trafficking for membrane expansion and axon outgrowth remain unclear. Here, we show that Rab33a expression became upregulated during axon outgrowth of cultured rat hippocampal neurons. Rab33a was preferentially localized to the Golgi apparatus and to synaptophysin-positive vesicles that are transported along the growing axon. Previous studies showed that synaptophysin is localized to post-Golgi vesicles transported by fast axonal transport in developing neurons. Reduction of Rab33a expression by RNAi (RNA interference) inhibited the anterograde transport of synaptophysin-positive vesicles, leading to their decrease in axonal tips. Furthermore, this treatment reduced membrane fusion of synaptophysin-positive vesicles at the growth cones and inhibited axon outgrowth. Overexpression of Rab33a, on the other hand, induced excessive accumulation of synaptophysin-positive vesicles and concurrent formation of surplus axons. These data suggest that Rab33a participates in axon outgrowth by mediating anterograde axonal transport of synaptophysin-positive vesicles and their concomitant fusion at the growth cones.
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Abstract
Growth cone collapse is a crucial process for repulsive axon guidance and is accompanied by a reduction in growth cone surface area. This process of reduction may be regulated by endocytosis; however, its molecular mechanism is unclear. Macropinocytosis is a clathrin-independent form of endocytosis in which large areas of plasma membrane can be engulfed. We have reported previously that macropinocytosis is induced in growth cones of chick dorsal root ganglion neurons by semaphorin 3A (Sema3A), a repulsive axon guidance cue, and that Sema3A-induced reduction in growth cone surface area and macropinocytic vacuole area were correlated, suggesting a positive role for macropinocytosis in Sema3A-induced growth cone collapse. In the present study, we found that syntaxin 1B (Syx1B), a membrane trafficking protein, is a negative regulator of macropinocytosis, and its expression is downregulated by Sema3A signaling. Macropinocytosis inhibitor ethylisopropylamiloride or Syx1B overexpression suppressed Sema3A-induced macropinocytosis and growth cone collapse. These results indicate that Syx1B couples macropinocytosis-mediated massive internalization of the plasma membrane to Sema3A-induced growth cone collapse.
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Magharious M, D'Onofrio PM, Hollander A, Zhu P, Chen J, Koeberle PD. Quantitative iTRAQ analysis of retinal ganglion cell degeneration after optic nerve crush. J Proteome Res 2011; 10:3344-62. [PMID: 21627321 DOI: 10.1021/pr2004055] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Retinal ganglion cells (RGCs) are central nervous system (CNS) neurons that transmit visual information from the retina to the brain. Apoptotic RGC degeneration causes visual impairment that can be modeled by optic nerve crush. Neuronal apoptosis is also a salient feature of CNS trauma, ischemia (stroke), and diseases of the CNS such as Alzheimer's, Parkinson's, multiple sclerosis, and amyotrophic lateral sclerosis. Optic nerve crush induces the apoptotic cell death of ∼ 70% of RGCs within the first 14 days after injury. This model is particularly attractive for studying adult neuron apoptosis because the time-course of RGC death is well established and axon regeneration within the myelinated optic nerve can be concurrently evaluated. Here, we performed a large scale iTRAQ proteomic study to identify and quantify proteins of the rat retina at 1, 3, 4, 7, 14, and 21 days after optic nerve crush. In total, 337 proteins were identified, and 110 were differentially regulated after injury. Of these, 58 proteins were upregulated (>1.3 ×), 46 were downregulated (<0.7 ×), and 6 showed both positive and negative regulation over 21 days, relative to normal retinas. Among the differentially expressed proteins, Thymosin-β4 showed an early upregulation at 3 days, the time-point that immediately precedes the induction of RGC apoptosis after injury. We examined the effect of exogenous Thymosin-β4 administration on RGC death after optic nerve injury. Intraocular injections of Thymosin-β4 significantly increased RGC survival by ∼ 3-fold compared to controls and enhanced axon regeneration after crush, demonstrating therapeutic potential for CNS insults. Overall, our study identified numerous proteins that are differentially regulated at key time-points after optic nerve crush, and how the temporal profiles of their expression parallel RGC death. This data will aid in the future development of novel therapeutics to promote neuronal survival and regeneration in the adult CNS.
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Affiliation(s)
- Mark Magharious
- Graduate Department of Rehabilitation Science, University of Toronto, Canada
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Bloom OE, Morgan JR. Membrane trafficking events underlying axon repair, growth, and regeneration. Mol Cell Neurosci 2011; 48:339-48. [PMID: 21539917 DOI: 10.1016/j.mcn.2011.04.003] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2011] [Revised: 04/11/2011] [Accepted: 04/14/2011] [Indexed: 12/31/2022] Open
Abstract
Two central challenges for the field of neurobiology are to understand how axons grow and make proper synaptic connections under normal conditions and how they repair their membranes and mount regenerative responses after injury. At the most reductionist level, the first step toward addressing these challenges is to delineate the cellular and molecular processes by which an axon extends from its cell body. Underlying axon extension are questions of appropriate timing and mechanisms that establish or maintain the axon's polarity, initiate growth cone formation, and promote axon outgrowth and synapse formation. After injury, the problem is even more complicated because the neuron must also repair its damaged membrane, redistribute or manufacture what it needs in order to survive, and grow and form new synapses within a more mature, complex environment. While other reviews have focused extensively on the signaling events and cytoskeletal rearrangements that support axon outgrowth and regeneration, we focus this review instead on the underlying membrane trafficking events underlying these processes. Though the mechanisms are still under active investigation, the key roles played by membrane trafficking events during axon repair, growth, and regeneration have been elucidated through elegant comparative studies in both invertebrate and vertebrate organisms. Taken together, a model emerges indicating that the critical requirements for ensuring proper membrane sealing and axon extension include iterative bouts of SNARE mediated exocytosis, endocytosis, and functional links between vesicles and the actin cytoskeleton, similar to the mechanisms utilized during synaptic transmission. This article is part of a Special Issue entitled 'Neuronal Function'.
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Affiliation(s)
- Ona E Bloom
- The Center for Autoimmune and Musculoskeletal Disease, The Feinstein Institute for Medical Research, 350 Community Drive, Manhasset, NY 11030, USA
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Fukushima T, Takasusuki T, Tomitori H, Hori Y. Possible involvement of syntaxin 1A downregulation in the late phase of allodynia induced by peripheral nerve injury. Neuroscience 2011; 175:344-57. [DOI: 10.1016/j.neuroscience.2010.11.049] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2010] [Revised: 11/11/2010] [Accepted: 11/22/2010] [Indexed: 11/16/2022]
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Expression and function of neuronal growth-associated proteins (nGAPs) in PC12 cells. Neurosci Res 2011; 70:85-90. [PMID: 21238513 DOI: 10.1016/j.neures.2011.01.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2010] [Revised: 01/02/2011] [Accepted: 01/04/2011] [Indexed: 11/21/2022]
Abstract
The growth cone plays crucial roles in neural wiring, synapse formation, and axonal regeneration. Continuous rearrangement of cytoskeletal elements and targeting of transported vesicles to the plasma membrane are essential to growth cone motility; however, the proteins directly involved in these processes and their specific functions are not well established. We recently identified 17 proteins as functional marker proteins of the mammalian growth cone and as neuronal growth-associated proteins in rat cortical neurons (nGAPs; Nozumi et al., 2009). To determine whether these 17 proteins are growth cone markers in other neuronal cell types, we examined their expression and function in PC12D cells. We found that all 17 nGAPs were highly concentrated in the growth cones of PC12D cells, and that knockdown of all of them by RNAi reduced or inhibited neurite outgrowth, indicating that all of the 17 nGAPs may be general growth cone markers. Among them, eight proteins were shown to regulate the amount of F-actin in PC12D growth cones. Two of these nGAP that are cytoskeletal proteins, Cap1 and Sept2, increased the mean growth cone area and the mean neurite length by regulating the amount of F-actin; Sept2 also induced filopodial growth. Taken together, our data suggested that some of the nGAPs were generalized markers of the growth cone in multiple neuronal cell types and some of them, such as Cap1 and Sept2, regulated growth cone morphology through rearrangement of F-actin and thereby controlled neurite outgrowth.
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Abstract
BACKGROUND INFORMATION During development, growth cones of outgrowing neurons express proteins involved in vesicular secretion, such as SNARE (soluble N-ethylmaleimide-sensitive fusion protein-attachment protein receptor) proteins, Munc13 and Munc18. Vesicles are known to fuse in growth cones prior to synapse formation, which may contribute to outgrowth. RESULTS We tested this possibility in dissociated cell cultures and organotypic slice cultures of two release-deficient mice (Munc18-1 null and Munc13-1/2 double null). Both types of release-deficient neurons have a decreased outgrowth speed and therefore have a smaller total neurite length during early development [DIV1-4 (day in vitro 1-4)]. In addition, more filopodia per growth cone were observed in Munc18-1 null, but not WT (wild-type) or Munc13-1/2 double null neurons. The smaller total neurite length during early development was no longer observed after synaptogenesis (DIV14-23). CONCLUSION These data suggest that the inability of vesicle fusion in the growth cone affects outgrowth during the initial phases when outgrowth speed is high, but not during/after synaptogenesis. Overall, the outgrowth speed is probably not rate-limiting during neuronal network formation, at least in vitro. In addition, Munc18, but not Munc13, regulates growth cone filopodia, potentially via its previously observed effect on filamentous actin.
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Identification of functional marker proteins in the mammalian growth cone. Proc Natl Acad Sci U S A 2009; 106:17211-6. [PMID: 19805073 DOI: 10.1073/pnas.0904092106] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Identification of proteins in the mammalian growth cone has the potential to advance our understanding of this critical regulator of neuronal growth and formation of neural circuit; however, to date, only one growth cone marker protein, GAP-43, has been reported. Here, we successfully used a proteomic approach to identify 945 proteins present in developing rat forebrain growth cones, including highly abundant, membrane-associated and actin-associated proteins. Almost 100 of the proteins appear to be highly enriched in the growth cone, as determined by quantitative immunostaining, and for 17 proteins, the results of RNAi suggest a role in axon growth. Most of the proteins we identified have not previously been implicated in axon growth and thus their identification presents a significant step forward, providing marker proteins and candidate neuronal growth-associated proteins.
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Coffield JA, Yan X. Neuritogenic actions of botulinum neurotoxin A on cultured motor neurons. J Pharmacol Exp Ther 2009; 330:352-8. [PMID: 19372387 DOI: 10.1124/jpet.108.147744] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Botulinum neurotoxins (BoNTs) are extremely potent neuromuscular poisons that act through soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) protein cleavage to inhibit neurotransmitter release. The ability of BoNT serotype A (BoNT/A) to eliminate localized transmitter release at extremely low doses is well characterized. In the current study, we investigated the less understood characteristic of BoNT/A to induce nerve outgrowth, sometimes referred to as sprouting. This phenomenon is generally considered a secondary response to the paralytic actions of BoNT/A, and other potential factors that may initiate this sprouting have not been investigated. Alternatively, we hypothesized that BoNT/A induces sprouting through presynaptic receptor activation that is independent of its known intracellular actions on the soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) synaptosomal associated protein of 25 kDa (SNAP-25). To test this, the effects of BoNT/A application on neurite outgrowth were examined using primary cultures enriched with motor neurons isolated from embryonic mouse spinal cord. In this system, BoNT/A potently stimulated neuritogenesis at concentrations as low as 0.01 nM. The neuritogenic effects of BoNT/A exposure were concentration dependent and antagonized by Triticum vulgaris lectin, a known competitive antagonist of BoNT. Similar results were observed with the isolated BoNT/A binding domain, revealing that neuritogenesis could be initiated solely by the binding actions of BoNT/A. In addition, the presence or absence of SNAP-25 cleavage by BoNT/A was not a determinant factor in BoNT/A-induced neuritogenesis. Collectively, these results suggest that binding of BoNT/A to the motor neuronal membrane activates neuritogenesis through as yet undetermined intracellular pathway(s), independent of its known action on vesicular release.
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Affiliation(s)
- Julie A Coffield
- Department of Physiology and Pharmacology, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA.
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Abstract
The formation of axons and dendrites and maintenance of the neuron's vastly expanded surface require the continuous addition of new membrane. This is achieved by membrane synthesis through the secretory pathway followed by regulated vesicle fusion with the plasma membrane, typically in the distal neurite. However, it is far from simple: multiple distinct membrane carriers are used to target specific membrane domains, dendrites seem to operate semi-autonomously from the rest of the neuron, and exocytosis for membrane expansion is different from that for release of synaptic vesicles. Current knowledge of this process and its implications for neuronal development, function and repair are reviewed.
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Nuclear localization of a novel human syntaxin 1B isoform. Gene 2008; 423:160-71. [DOI: 10.1016/j.gene.2008.07.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2008] [Revised: 06/20/2008] [Accepted: 07/07/2008] [Indexed: 12/23/2022]
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Kabayama H, Nakamura T, Takeuchi M, Iwasaki H, Taniguchi M, Tokushige N, Mikoshiba K. Ca2+ induces macropinocytosis via F-actin depolymerization during growth cone collapse. Mol Cell Neurosci 2008; 40:27-38. [PMID: 18848894 DOI: 10.1016/j.mcn.2008.08.009] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2008] [Revised: 08/26/2008] [Accepted: 08/27/2008] [Indexed: 02/02/2023] Open
Abstract
Growth cone collapse occurs in repulsive axon guidance and is accompanied by a reduction in the surface area of the plasma membrane of growth cones. However, the mechanism of this reduction is unclear. Here, we show that during growth cone collapse, caffeine-induced Ca(2+) release from ryanodine-sensitive Ca(2+) stores triggers the formation of large vacuoles in growth cones by macropinocytosis, a clathrin-independent endocytosis for the massive retrieval of the cellular plasma membrane, and subsequent retrograde membrane transport. We observed a significant correlation of the area of caffeine-induced macropinosomes with growth cone collapse. We also detected macropinocytosis induced by semaphorin 3A, a typical repulsive cue, and correlation between the area of semaphorin 3A-induced macropinocytic vacuoles and growth cone collapse. Moreover, jasplakinolide, an inhibitor of F-actin depolymerization, blocked caffeine-induced macropinocytosis. We propose that the coordinated regulation of actin cytoskeletal reorganization and macropinocytosis-mediated retrograde membrane trafficking may contribute to Ca(2+)-induced axon growth inhibition.
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Affiliation(s)
- Hiroyuki Kabayama
- Laboratory for Developmental Neurobiology, Brain Science Institute, The Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
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Syntaxin 6 regulates nerve growth factor-dependent neurite outgrowth. Neurosci Lett 2008; 436:340-4. [DOI: 10.1016/j.neulet.2008.03.061] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2007] [Revised: 03/11/2008] [Accepted: 03/20/2008] [Indexed: 11/18/2022]
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Takasusuki T, Fujiwara T, Yamaguchi S, Fukushima T, Akagawa K, Hori Y. Enhancement of synaptic transmission and nociceptive behaviour in HPC-1/syntaxin 1A knockout mice following peripheral nerve injury. Eur J Neurosci 2008; 26:2179-87. [PMID: 17953616 DOI: 10.1111/j.1460-9568.2007.05830.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Our previous analysis of HPC-1/syntaxin 1A knockout (KO) mice indicated that HPC-1/syntaxin 1A plays an important role in the synaptic plasticity of the hippocampus in vitro and learning behaviour in vivo. In order to gain further insights into the physiological functions of HPC-1/syntaxin 1A, we studied the changes in the plasticity of synaptic transmission in the superficial dorsal horn of the spinal cord following a peripheral nerve injury in HPC-1/syntaxin 1A KO and wild-type (WT) mice. The von Frey filament test revealed that partial ligation of the sciatic nerve caused neuropathic pain in both WT and KO mice. However, KO mice showed significant enhancement of mechanical allodynia as compared with WT mice. Tight-seal whole-cell recordings were obtained from neurons in the superficial dorsal horn of the spinal cord slices. Electrical stimulus-evoked excitatory postsynaptic currents (EPSCs), asynchronous EPSCs (aEPSCs) in the presence of strontium, and spontaneously occurring miniature EPSCs (mEPSCs) were analysed. Prior to peripheral nerve ligation, no significant differences were observed in the properties of evoked EPSCs, aEPSCs and mEPSCs in KO and WT mice. Seven-14 days after partial ligation, the amplitude of evoked EPSCs and the frequency of aEPSCs and mEPSCs in KO mice were significantly greater than those in WT mice; however, the amplitude of aEPSCs and mEPSCs remained unchanged in both groups. Enhanced allodynia behaviour and significant enhancement of excitatory synaptic transmission following peripheral nerve ligation in KO mice suggest that HPC-1/syntaxin 1A might play a role in synaptic plasticity in the nociceptive pathway.
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Affiliation(s)
- T Takasusuki
- Department of Physiology and Biological Information, Dokkyo Medical University, Tochigi 321-0293, Japan
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Abstract
Toxins that alter neurotransmitter release from nerve terminals are of considerable scientific and clinical importance. Many advances were recently made in the understanding of their molecular mechanisms of action and use in human therapy. Here, we focus on presynaptic neurotoxins, which are very potent inhibitors of the neurotransmitter release because they are endowed with specific enzymatic activities: (1) clostridial neurotoxins with a metallo-proteolytic activity and (2) snake presynaptic neurotoxins with a phospholipase A2 activity.
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Affiliation(s)
- Ornella Rossetto
- Departimento de Scienze Biomediche and Istituto CNR di Neuroscienze, Universita di Padova, Viale G. Colombo 3, 35121, Padova, Italy
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Abstract
A recent study has demonstrated for the first time that botulinum neurotoxin (BoNT) briefly opens tumour vessels, allowing more effective destruction of cancer cells by radiotherapy and chemotherapy. This review discusses the implications of BoNTs in cancer treatment. After briefly reviewing the different BoNT serotypes, their pharmacological activities and their general use in medicine, the authors focus on their possible application in cancer and describe how BoNTs have been used so far to treat spasm related to tumour or to therapies. By dissecting the mechanisms of action leading to a potentiation of anticancer therapy, it can be seen that BoNTs act by an effect on the tumour microenvironment rather than by a direct cytotoxic effect on tumour cells.
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Affiliation(s)
- Réginald Ansiaux
- Biomedical Magnetic Resonance Unit, Department of Pharmaceutical Sciences, Avenue Mounier 73.40, B-1200 Brussels, Belgium
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Tojima T, Akiyama H, Itofusa R, Li Y, Katayama H, Miyawaki A, Kamiguchi H. Attractive axon guidance involves asymmetric membrane transport and exocytosis in the growth cone. Nat Neurosci 2006; 10:58-66. [PMID: 17159991 DOI: 10.1038/nn1814] [Citation(s) in RCA: 134] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2006] [Accepted: 11/17/2006] [Indexed: 12/22/2022]
Abstract
Asymmetric elevation of the Ca(2+) concentration in the growth cone can mediate both attractive and repulsive axon guidance. Ca(2+) signals that are accompanied by Ca(2+)-induced Ca(2+) release (CICR) trigger attraction, whereas Ca(2+) signals that are not accompanied by CICR trigger repulsion. The molecular machinery downstream of Ca(2+) signals, however, remains largely unknown. Here we report that asymmetric membrane trafficking mediates growth cone attraction. Local photolysis of caged Ca(2+), together with CICR, on one side of the growth cone of a chick dorsal root ganglion neuron facilitated the microtubule-dependent centrifugal transport of vesicles towards the leading edge and their subsequent vesicle-associated membrane-protein 2 (VAMP2)-mediated exocytosis on the side with an elevated Ca(2+) concentration. In contrast, Ca(2+) signals without CICR had no effect on the vesicle transport. Furthermore, pharmacological inhibition of VAMP2-mediated exocytosis prevented growth cone attraction, but not repulsion. These results strongly suggest that growth cone attraction and repulsion are driven by distinct mechanisms, rather than using the same molecular machinery with opposing polarities.
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Affiliation(s)
- Takuro Tojima
- Laboratory for Neuronal Growth Mechanisms, Brain Science Institute, The Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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Sherry DM, Mitchell R, Standifer KM, du Plessis B. Distribution of plasma membrane-associated syntaxins 1 through 4 indicates distinct trafficking functions in the synaptic layers of the mouse retina. BMC Neurosci 2006; 7:54. [PMID: 16839421 PMCID: PMC1555595 DOI: 10.1186/1471-2202-7-54] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2006] [Accepted: 07/13/2006] [Indexed: 01/02/2023] Open
Abstract
Background Syntaxins 1 through 4 are SNAP receptor (SNARE) proteins that mediate vesicular trafficking to the plasma membrane. In retina, syntaxins 1 and 3 are expressed at conventional and ribbon synapses, respectively, suggesting that synaptic trafficking functions differ among syntaxin isoforms. To better understand syntaxins in synaptic signaling and trafficking, we further examined the cell- and synapse-specific expression of syntaxins 1 through 4 in the mouse retina by immunolabeling and confocal microscopy. Results Each isoform was expressed in the retina and showed a unique distribution in the synaptic layers of the retina, with little or no colocalization of isoforms. Syntaxin 1 was present in amacrine cell bodies and processes and conventional presynaptic terminals in the inner plexiform layer (IPL). Syntaxin 2 was present in amacrine cells and their processes in the IPL, but showed little colocalization with syntaxin 1 or other presynaptic markers. Syntaxin 3 was found in glutamatergic photoreceptor and bipolar cell ribbon synapses, but was absent from putative conventional glutamatergic amacrine cell synapses. Syntaxin 4 was localized to horizontal cell processes in the ribbon synaptic complexes of photoreceptor terminals and in puncta in the IPL that contacted dopaminergic and CD15-positive amacrine cells. Syntaxins 2 and 4 often were apposed to synaptic active zones labeled for bassoon. Conclusion These results indicate that each syntaxin isoform has unique, non-redundant functions in synaptic signaling and trafficking. Syntaxins 1 and 3 mediate presynaptic transmitter release from conventional and ribbon synapses, respectively. Syntaxins 2 and 4 are not presynaptic and likely mediate post-synaptic trafficking.
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Affiliation(s)
- David M Sherry
- University of Houston, College of Optometry, Houston, TX 77204, USA
- College of Pharmacy, Department of Pharmacological and Pharmaceutical Sciences, University of Houston, Houston, TX 77204, USA
| | - Robert Mitchell
- University of Houston, College of Optometry, Houston, TX 77204, USA
| | - Kelly M Standifer
- College of Pharmacy, Department of Pharmacological and Pharmaceutical Sciences, University of Houston, Houston, TX 77204, USA
| | - Brad du Plessis
- University of Houston, College of Optometry, Houston, TX 77204, USA
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Fujiwara T, Mishima T, Kofuji T, Chiba T, Tanaka K, Yamamoto A, Akagawa K. Analysis of knock-out mice to determine the role of HPC-1/syntaxin 1A in expressing synaptic plasticity. J Neurosci 2006; 26:5767-76. [PMID: 16723534 PMCID: PMC6675267 DOI: 10.1523/jneurosci.0289-06.2006] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The protein HPC-1/syntaxin 1A is abundantly expressed in neurons and localized in the neuronal plasma membrane. It forms a complex with SNAP-25 (25 kDa synaptosomal-associated protein) and VAMP-2 (vesicle-associated membrane protein)/synaptobrevin called SNARE (a soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor) complex, which is considered essential for synaptic vesicle exocytosis; thus, HPC-1/syntaxin 1A is considered crucial for synaptic transmission. To examine the physiological function of HPC-1/syntaxin 1A in vivo, we produced knock-out (KO) mice by targeted gene disruption. Although HPC-1/syntaxin 1A expression was completely depleted without any effect on the expression of other SNARE proteins, the KO mice were viable. They grew normally, were fertile, and displayed no difference in appearance compared with control littermate. In cultured hippocampal neurons derived from the KO mice, the basic synaptic transmission in vitro was normal. However, the mutant mice had impaired long-term potentiation in the hippocampal slice. Also, although KO mice exhibited normal spatial memory in the hidden platform test, consolidation of conditioned fear memory was impaired. Interestingly, the KO mice had impaired conditioned fear memory extinction. These observations suggest that HPC-1/syntaxin 1A may be closely related to synaptic plasticity.
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Affiliation(s)
- Tomonori Fujiwara
- Department of Cell Physiology, Kyorin University School of Medicine, Mitaka, Tokyo 181-8611, Japan.
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47
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Abstract
Proteins such as UNC-76 that associate with kinesin motors are important in directing neurite extension. A small Caenorhabditis elegans coiled-coil protein, UNC-69, has now been shown to interact with UNC-76 and to be involved in axonal (but not dendritic) transport and outgrowth, as well as synapse formation.
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Affiliation(s)
- Shuo Luo
- Department of Anatomy and Neurobiology, Washington University School of Medicine, 660 S. Euclid Avenue, Saint Louis, MO 63110, USA
| | - Michael L Nonet
- Department of Anatomy and Neurobiology, Washington University School of Medicine, 660 S. Euclid Avenue, Saint Louis, MO 63110, USA
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Darios F, Davletov B. Omega-3 and omega-6 fatty acids stimulate cell membrane expansion by acting on syntaxin 3. Nature 2006; 440:813-7. [PMID: 16598260 DOI: 10.1038/nature04598] [Citation(s) in RCA: 251] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2005] [Accepted: 12/21/2005] [Indexed: 11/09/2022]
Abstract
Growth of neurite processes from the cell body is the critical step in neuronal development and involves a large increase in cell membrane surface area. Arachidonic-acid-releasing phospholipases are highly enriched in nerve growth cones and have previously been implicated in neurite outgrowth. Cell membrane expansion is achieved through the fusion of transport organelles with the plasma membrane; however, the identity of the molecular target of arachidonic acid has remained elusive. Here we show that syntaxin 3 (STX3), a plasma membrane protein, has an important role in the growth of neurites, and also serves as a direct target for omega-6 arachidonic acid. By using syntaxin 3 in a screening assay, we determined that the dietary omega-3 linolenic and docosahexaenoic acids can efficiently substitute for arachidonic acid in activating syntaxin 3. Our findings provide a molecular basis for the previously established action of omega-3 and omega-6 polyunsaturated fatty acids in membrane expansion at the growth cones, and represent the first identification of a single effector molecule for these essential nutrients.
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Affiliation(s)
- Frédéric Darios
- MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK
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49
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Bajohrs M, Darios F, Peak-Chew SY, Davletov B. Promiscuous interaction of SNAP-25 with all plasma membrane syntaxins in a neuroendocrine cell. Biochem J 2006; 392:283-9. [PMID: 15975093 PMCID: PMC1316263 DOI: 10.1042/bj20050583] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
SNAP-25 (25 kDa synaptosome-associated protein) is found in cells that release neurotransmitters and hormones, and plays a central role in the fusion of secretory vesicles with the plasma membrane. SNAP-25 has been shown to interact specifically with syntaxin 1, a 35 kDa membrane protein, to mediate the fusion process. Here, we investigated whether other known syntaxin isoforms found at the plasma membrane can serve as binding partners for SNAP-25 in vivo. In our analysis, we employed rat phaeochromocytoma PC12 cells that are often used as a model of neuronal functions. We now show that these cells contain large amounts of SNAP-25, which interacts not only with syntaxin 1, but also with ubiquitous syntaxins 2, 3 and 4. The plasma membrane syntaxins appear to occupy complementary domains at the plasma membrane. In defined reactions, the ubiquitous plasma membrane syntaxin isoforms, when in binary complexes with SNAP-25, readily bound vesicular synaptobrevin to form SDS-resistant SNARE (soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor) complexes implicated in membrane fusion. However, vesicular synaptotagmin and cytosolic complexin, both implicated in the fusion process, exhibited differential ability to interact with the SNARE complexes formed by syntaxins 1-4, suggesting that the plasma membrane syntaxins may mediate vesicle fusion events with different properties.
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Affiliation(s)
- Mark Bajohrs
- MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, U.K
| | - Frédéric Darios
- MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, U.K
| | - Sew-Yeu Peak-Chew
- MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, U.K
| | - Bazbek Davletov
- MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, U.K
- To whom correspondence should be addressed (email )
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Hagiwara A, Fukazawa Y, Deguchi-Tawarada M, Ohtsuka T, Shigemoto R. Differential distribution of release-related proteins in the hippocampal CA3 area as revealed by freeze-fracture replica labeling. J Comp Neurol 2005; 489:195-216. [PMID: 15983999 DOI: 10.1002/cne.20633] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Synaptic vesicle release occurs at a specialized membrane domain known as the presynaptic active zone (AZ). Several membrane proteins are involved in the vesicle release processes such as docking, priming, and exocytotic fusion. Cytomatrix at the active zone (CAZ) proteins are structural components of the AZ and are highly concentrated in it. Localization of other release-related proteins including target soluble N-ethylmaleimide-sensitive-factor attachment protein receptor (t-SNARE) proteins, however, has not been well demonstrated in the AZ. Here, we used sodium dodecyl sulfate-digested freeze-fracture replica labeling (SDS-FRL) to analyze quantitatively the distribution of CAZ and t-SNARE proteins in the hippocampal CA3 area. The AZ in replicated membrane was identified by immunolabeling for CAZ proteins (CAZ-associated structural protein [CAST] and Bassoon). Clusters of immunogold particles for these proteins were found on the P-face of presynaptic terminals of the mossy fiber and associational/commissural (A/C) fiber. Co-labeling with CAST revealed distribution of the t-SNARE proteins syntaxin and synaptosomal-associated protein of 25 kDa (SNAP-25) in the AZ as well as in the extrasynaptic membrane surrounding the AZ (SZ). Quantitative analysis demonstrated that the density of immunoparticles for CAST in the AZ was more than 100 times higher than in the SZ, whereas that for syntaxin and SNAP-25 was not significantly different between the AZ and SZ in both the A/C and mossy fiber terminals. These results support the involvement of the t-SNARE proteins in exocytotic fusion in the AZ and the role of CAST in specialization of the membrane domain for the AZ.
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Affiliation(s)
- Akari Hagiwara
- Division of Cerebral Structure, National Institute for Physiological Sciences, Okazaki 444-8787, Japan.
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