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Xiong GJ, Sheng ZH. Presynaptic perspective: Axonal transport defects in neurodevelopmental disorders. J Cell Biol 2024; 223:e202401145. [PMID: 38568173 PMCID: PMC10988239 DOI: 10.1083/jcb.202401145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2024] [Revised: 03/20/2024] [Accepted: 03/21/2024] [Indexed: 04/05/2024] Open
Abstract
Disruption of synapse assembly and maturation leads to a broad spectrum of neurodevelopmental disorders. Presynaptic proteins are largely synthesized in the soma, where they are packaged into precursor vesicles and transported into distal axons to ensure precise assembly and maintenance of presynapses. Due to their morphological features, neurons face challenges in the delivery of presynaptic cargos to nascent boutons. Thus, targeted axonal transport is vital to build functional synapses. A growing number of mutations in genes encoding the transport machinery have been linked to neurodevelopmental disorders. Emerging lines of evidence have started to uncover presynaptic mechanisms underlying axonal transport defects, thus broadening the view of neurodevelopmental disorders beyond postsynaptic mechanisms. In this review, we discuss presynaptic perspectives of neurodevelopmental disorders by focusing on impaired axonal transport and disturbed assembly and maintenance of presynapses. We also discuss potential strategies for restoring axonal transport as an early therapeutic intervention.
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Affiliation(s)
- Gui-Jing Xiong
- Synaptic Function Section, The Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Zu-Hang Sheng
- Synaptic Function Section, The Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
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2
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Jin X, Si X, Lei X, Liu H, Shao A, Li L. Disruption of Dopamine Homeostasis Associated with Alteration of Proteins in Synaptic Vesicles: A Putative Central Mechanism of Parkinson's Disease Pathogenesis. Aging Dis 2024; 15:1204-1226. [PMID: 37815908 PMCID: PMC11081171 DOI: 10.14336/ad.2023.0821-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Accepted: 08/21/2023] [Indexed: 10/12/2023] Open
Abstract
Vestigial dopaminergic cells in PD have selectivity for a sub-class of hypersensitive neurons with the nigrostriatal dopamine (DA) tract. DA is modulated in pre-synaptic nerve terminals to remain stable. To be specific, proteins at DA release sites that have a function of synthesizing and packing DA in cytoplasm, modulating release and reingestion, and changing excitability of neurons, display regional discrepancies that uncover relevancy of the observed sensitivity to neurodegenerative changes. Although the reasons of a majority of PD cases are still indistinct, heredity and environment are known to us to make significant influences. For decades, genetic analysis of PD patients with heredity in family have promoted our comprehension of pathogenesis to a great extent, which reveals correlative mechanisms including oxidative stress, abnormal protein homeostasis and mitochondrial dysfunction. In this review, we review the constitution of presynaptic vesicle related to DA homeostasis and describe the genetic and environmental evidence of presynaptic dysfunction that increase risky possibility of PD concerning intracellular vesicle transmission and their functional outcomes. We summarize alterations in synaptic vesicular proteins with great involvement in the reasons of some DA neurons highly vulnerable to neurodegenerative changes. We generalize different potential targets and therapeutic strategies for different pathogenic mechanisms, providing a reference for further studies of PD treatment in the future. But it remains to be further researched on this recently discovered and converging mechanism of vesicular dynamics and PD, which will provide a more profound comprehension and put up with new therapeutic tactics for PD patients.
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Affiliation(s)
- Xuanxiang Jin
- The First School of Medicine, School of Information and Engineering, Wenzhou Medical University, Wenzhou, Zhejiang, China.
| | - Xiaoli Si
- Department of Neurology, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.
| | - Xiaoguang Lei
- Department of Neurology, First Affiliated Hospital of Kunming Medical University, the First School of Clinical Medicine, Kunming Medical University, Kunming, China.
| | - Huifang Liu
- Division of Neurology, Department of Medicine, University of Hong Kong, Hong Kong.
| | - Anwen Shao
- Department of Neurosurgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.
- Key Laboratory of Precise Treatment and Clinical Translational Research of Neurological Disease, Hangzhou, China.
| | - Lingfei Li
- Department of Neurology, Affiliated Hangzhou First People’s Hospital, Zhejiang University School of Medicine, Hangzhou, China.
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3
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Zhu Y, Akkaya KC, Ruta J, Yokoyama N, Wang C, Ruwolt M, Lima DB, Lehmann M, Liu F. Cross-link assisted spatial proteomics to map sub-organelle proteomes and membrane protein topologies. Nat Commun 2024; 15:3290. [PMID: 38632225 PMCID: PMC11024108 DOI: 10.1038/s41467-024-47569-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Accepted: 04/05/2024] [Indexed: 04/19/2024] Open
Abstract
The functions of cellular organelles and sub-compartments depend on their protein content, which can be characterized by spatial proteomics approaches. However, many spatial proteomics methods are limited in their ability to resolve organellar sub-compartments, profile multiple sub-compartments in parallel, and/or characterize membrane-associated proteomes. Here, we develop a cross-link assisted spatial proteomics (CLASP) strategy that addresses these shortcomings. Using human mitochondria as a model system, we show that CLASP can elucidate spatial proteomes of all mitochondrial sub-compartments and provide topological insight into the mitochondrial membrane proteome. Biochemical and imaging-based follow-up studies confirm that CLASP allows discovering mitochondria-associated proteins and revising previous protein sub-compartment localization and membrane topology data. We also validate the CLASP concept in synaptic vesicles, demonstrating its applicability to different sub-cellular compartments. This study extends the scope of cross-linking mass spectrometry beyond protein structure and interaction analysis towards spatial proteomics, and establishes a method for concomitant profiling of sub-organelle and membrane proteomes.
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Affiliation(s)
- Ying Zhu
- Department of Structural Biology, Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Roessle-Str. 10 13125, Berlin, Germany
| | - Kerem Can Akkaya
- Department of Structural Biology, Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Roessle-Str. 10 13125, Berlin, Germany
- Department of Molecular Physiology and Cell Biology, Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Roessle-Str. 10 13125, Berlin, Germany
| | - Julia Ruta
- Department of Structural Biology, Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Roessle-Str. 10 13125, Berlin, Germany
| | - Nanako Yokoyama
- Department of Structural Biology, Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Roessle-Str. 10 13125, Berlin, Germany
| | - Cong Wang
- Department of Structural Biology, Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Roessle-Str. 10 13125, Berlin, Germany
| | - Max Ruwolt
- Department of Structural Biology, Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Roessle-Str. 10 13125, Berlin, Germany
| | - Diogo Borges Lima
- Department of Structural Biology, Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Roessle-Str. 10 13125, Berlin, Germany
| | - Martin Lehmann
- Department of Molecular Physiology and Cell Biology, Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Roessle-Str. 10 13125, Berlin, Germany
| | - Fan Liu
- Department of Structural Biology, Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Roessle-Str. 10 13125, Berlin, Germany.
- Charité - Universitätsmedizin Berlin, Charitépl. 1, 10117, Berlin, Germany.
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4
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Vlasova AD, Bukhalovich SM, Bagaeva DF, Polyakova AP, Ilyinsky NS, Nesterov SV, Tsybrov FM, Bogorodskiy AO, Zinovev EV, Mikhailov AE, Vlasov AV, Kuklin AI, Borshchevskiy VI, Bamberg E, Uversky VN, Gordeliy VI. Intracellular microbial rhodopsin-based optogenetics to control metabolism and cell signaling. Chem Soc Rev 2024; 53:3327-3349. [PMID: 38391026 DOI: 10.1039/d3cs00699a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2024]
Abstract
Microbial rhodopsin (MRs) ion channels and pumps have become invaluable optogenetic tools for neuroscience as well as biomedical applications. Recently, MR-optogenetics expanded towards subcellular organelles opening principally new opportunities in optogenetic control of intracellular metabolism and signaling via precise manipulations of organelle ion gradients using light. This new optogenetic field expands the opportunities for basic and medical studies of cancer, cardiovascular, and metabolic disorders, providing more detailed and accurate control of cell physiology. This review summarizes recent advances in studies of the cellular metabolic processes and signaling mediated by optogenetic tools targeting mitochondria, endoplasmic reticulum (ER), lysosomes, and synaptic vesicles. Finally, we discuss perspectives of such an optogenetic approach in both fundamental and applied research.
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Affiliation(s)
- Anastasiia D Vlasova
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Siarhei M Bukhalovich
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Diana F Bagaeva
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Aleksandra P Polyakova
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Nikolay S Ilyinsky
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Semen V Nesterov
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Fedor M Tsybrov
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Andrey O Bogorodskiy
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Egor V Zinovev
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Anatolii E Mikhailov
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Alexey V Vlasov
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russia
| | - Alexander I Kuklin
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russia
| | - Valentin I Borshchevskiy
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russia
| | - Ernst Bamberg
- Max Planck Institute of Biophysics, Frankfurt am Main, Germany
| | - Vladimir N Uversky
- Department of Molecular Medicine and Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, USA.
| | - Valentin I Gordeliy
- Institut de Biologie Structurale Jean-Pierre Ebel, Université Grenoble Alpes-Commissariat à l'Energie Atomique et aux Energies Alternatives-CNRS, 38027 Grenoble, France.
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5
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Binotti B, Ninov M, Cepeda AP, Ganzella M, Matti U, Riedel D, Urlaub H, Sambandan S, Jahn R. ATG9 resides on a unique population of small vesicles in presynaptic nerve terminals. Autophagy 2024; 20:883-901. [PMID: 37881948 PMCID: PMC11062364 DOI: 10.1080/15548627.2023.2274204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 10/17/2023] [Indexed: 10/27/2023] Open
Abstract
In neurons, autophagosome biogenesis occurs mainly in distal axons, followed by maturation during retrograde transport. Autophagosomal growth depends on the supply of membrane lipids which requires small vesicles containing ATG9, a lipid scramblase essential for macroautophagy/autophagy. Here, we show that ATG9-containing vesicles are enriched in synapses and resemble synaptic vesicles in size and density. The proteome of ATG9-containing vesicles immuno-isolated from nerve terminals showed conspicuously low levels of trafficking proteins except of the AP2-complex and some enzymes involved in endosomal phosphatidylinositol metabolism. Super resolution microscopy of nerve terminals and isolated vesicles revealed that ATG9-containing vesicles represent a distinct vesicle population with limited overlap not only with synaptic vesicles but also other membranes of the secretory pathway, uncovering a surprising heterogeneity in their membrane composition. Our results are compatible with the view that ATG9-containing vesicles function as lipid shuttles that scavenge membrane lipids from various intracellular membranes to support autophagosome biogenesis.Abbreviations: AP: adaptor related protein complex: ATG2: autophagy related 2; ATG9: autophagy related 9; DNA PAINT: DNA-based point accumulation for imaging in nanoscale topography; DyMIN STED: dynamic minimum stimulated emission depletion; EL: endosome and lysosome; ER: endoplasmic reticulum; GA: Golgi apparatus; iBAQ: intensity based absolute quantification; LAMP: lysosomal-associated membrane protein; M6PR: mannose-6-phosphate receptor, cation dependent; Minflux: minimal photon fluxes; Mito: mitochondria; MS: mass spectrometry; PAS: phagophore assembly site; PM: plasma membrane; Px: peroxisome; RAB26: RAB26, member RAS oncogene family; RAB3A: RAB3A, member RAS oncogene family; RAB5A: RAB5A, member RAS oncogene family; SNARE: soluble N-ethylmaleimide-sensitive-factor attachment receptor; SVs: synaptic vesicles; SYP: synaptophysin; TGN: trans-Golgi network; TRAPP: transport protein particle; VTI1: vesicle transport through interaction with t-SNAREs.
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Affiliation(s)
- Beyenech Binotti
- Laboratory of Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Department of Biochemistry, Biocenter, University of Würzburg, Würzburg, Germany
| | - Momchil Ninov
- Laboratory of Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Bioanalytics, Institute of Clinical Chemistry, University Medical Center Göttingen, Germany
- Bioanalytical Mass Spectrometry, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Andreia P. Cepeda
- Bioanalytical Mass Spectrometry, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Marcelo Ganzella
- Laboratory of Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Ulf Matti
- Abberior Instruments GmbH, Göttingen, Germany
| | - Dietmar Riedel
- Facility for Transmission Electron Microscopy, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Henning Urlaub
- Bioanalytics, Institute of Clinical Chemistry, University Medical Center Göttingen, Germany
- Bioanalytical Mass Spectrometry, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Cluster of Excellence “Multiscale Bioimaging : from Molecular Machines to Networks of Excitable Cells” (MBExC), University of Göttingen, Göttingen, Germany
| | - Sivakumar Sambandan
- Laboratory of Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Synaptic Metal Ion Dynamics and Signalin, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Reinhard Jahn
- Laboratory of Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
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6
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Runwal GM, Edwards RH. The role of α-synuclein in exocytosis. Exp Neurol 2024; 373:114668. [PMID: 38147972 DOI: 10.1016/j.expneurol.2023.114668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 11/28/2023] [Accepted: 12/19/2023] [Indexed: 12/28/2023]
Abstract
The pathogenesis of degeneration in Parkinson's disease (PD) remains poorly understood but multiple lines of evidence have converged on the presynaptic protein α-synuclein (αsyn). αSyn has been shown to regulate several cellular processes, however, its normal function remains poorly understood. In this review, we will specifically focus on its role in exocytosis.
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Affiliation(s)
- Gautam M Runwal
- Departments of Neurology and Physiology, UCSF School of Medicine, United States of America; Departments of Neurology and Physiology, UCSF School of Medicine, United States of America- Aligning Science Across Parkinson's Collaborative Research Network, Chevy Chase, MD 20815, United States of America
| | - Robert H Edwards
- Departments of Neurology and Physiology, UCSF School of Medicine, United States of America; Departments of Neurology and Physiology, UCSF School of Medicine, United States of America- Aligning Science Across Parkinson's Collaborative Research Network, Chevy Chase, MD 20815, United States of America.
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7
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Michaud SA, Pětrošová H, Sinclair NJ, Kinnear AL, Jackson AM, McGuire JC, Hardie DB, Bhowmick P, Ganguly M, Flenniken AM, Nutter LMJ, McKerlie C, Smith D, Mohammed Y, Schibli D, Sickmann A, Borchers CH. Multiple reaction monitoring assays for large-scale quantitation of proteins from 20 mouse organs and tissues. Commun Biol 2024; 7:6. [PMID: 38168632 PMCID: PMC10762018 DOI: 10.1038/s42003-023-05687-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Accepted: 12/07/2023] [Indexed: 01/05/2024] Open
Abstract
Mouse is the mammalian model of choice to study human health and disease due to its size, ease of breeding and the natural occurrence of conditions mimicking human pathology. Here we design and validate multiple reaction monitoring mass spectrometry (MRM-MS) assays for quantitation of 2118 unique proteins in 20 murine tissues and organs. We provide open access to technical aspects of these assays to enable their implementation in other laboratories, and demonstrate their suitability for proteomic profiling in mice by measuring normal protein abundances in tissues from three mouse strains: C57BL/6NCrl, NOD/SCID, and BALB/cAnNCrl. Sex- and strain-specific differences in protein abundances are identified and described, and the measured values are freely accessible via our MouseQuaPro database: http://mousequapro.proteincentre.com . Together, this large library of quantitative MRM-MS assays established in mice and the measured baseline protein abundances represent an important resource for research involving mouse models.
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Affiliation(s)
- Sarah A Michaud
- University of Victoria-Genome British Columbia Proteomics Centre, Victoria, BC, Canada.
| | - Helena Pětrošová
- University of Victoria-Genome British Columbia Proteomics Centre, Victoria, BC, Canada
| | - Nicholas J Sinclair
- University of Victoria-Genome British Columbia Proteomics Centre, Victoria, BC, Canada
| | - Andrea L Kinnear
- University of Victoria-Genome British Columbia Proteomics Centre, Victoria, BC, Canada
| | - Angela M Jackson
- University of Victoria-Genome British Columbia Proteomics Centre, Victoria, BC, Canada
| | - Jamie C McGuire
- University of Victoria-Genome British Columbia Proteomics Centre, Victoria, BC, Canada
| | - Darryl B Hardie
- University of Victoria-Genome British Columbia Proteomics Centre, Victoria, BC, Canada
| | - Pallab Bhowmick
- University of Victoria-Genome British Columbia Proteomics Centre, Victoria, BC, Canada
| | - Milan Ganguly
- The Center for Phenogenomics, Toronto, ON, Canada
- The Hospital for Sick Children, Toronto, ON, Canada
| | - Ann M Flenniken
- The Center for Phenogenomics, Toronto, ON, Canada
- Sinai Health Lunenfeld-Tanenbaum Research Institute, Toronto, ON, Canada
| | - Lauryl M J Nutter
- The Center for Phenogenomics, Toronto, ON, Canada
- The Hospital for Sick Children, Toronto, ON, Canada
| | | | - Derek Smith
- University of Victoria-Genome British Columbia Proteomics Centre, Victoria, BC, Canada
| | - Yassene Mohammed
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Leiden, the Netherlands
- Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V, Dortmund, 44139, Germany
- Segal Cancer Proteomics Centre, Lady Davis Institute, Jewish General Hospital, McGill University, Montreal, QC, Canada
| | - David Schibli
- University of Victoria-Genome British Columbia Proteomics Centre, Victoria, BC, Canada
| | - Albert Sickmann
- Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V, Dortmund, 44139, Germany
| | - Christoph H Borchers
- Segal Cancer Proteomics Centre, Lady Davis Institute, Jewish General Hospital, McGill University, Montreal, QC, Canada.
- Gerald Bronfman Department of Oncology, Jewish General Hospital, Montreal, QC, Canada.
- Department of Experimental Medicine, McGill University, Montreal, QC, Canada.
- Department of Pathology, McGill University, Montreal, QC, Canada.
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8
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Rizalar FS, Lucht MT, Petzoldt A, Kong S, Sun J, Vines JH, Telugu NS, Diecke S, Kaas T, Bullmann T, Schmied C, Löwe D, King JS, Cho W, Hallermann S, Puchkov D, Sigrist SJ, Haucke V. Phosphatidylinositol 3,5-bisphosphate facilitates axonal vesicle transport and presynapse assembly. Science 2023; 382:223-230. [PMID: 37824668 PMCID: PMC10938084 DOI: 10.1126/science.adg1075] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 08/16/2023] [Indexed: 10/14/2023]
Abstract
Neurons relay information via specialized presynaptic compartments for neurotransmission. Unlike conventional organelles, the specialized apparatus characterizing the neuronal presynapse must form de novo. How the components for presynaptic neurotransmission are transported and assembled is poorly understood. Our results show that the rare late endosomal signaling lipid phosphatidylinositol 3,5-bisphosphate [PI(3,5)P2] directs the axonal cotransport of synaptic vesicle and active zone proteins in precursor vesicles in human neurons. Precursor vesicles are distinct from conventional secretory organelles, endosomes, and degradative lysosomes and are transported by coincident detection of PI(3,5)P2 and active ARL8 via kinesin KIF1A to the presynaptic compartment. Our findings identify a crucial mechanism that mediates the delivery of synaptic vesicle and active zone proteins to developing synapses.
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Affiliation(s)
- Filiz Sila Rizalar
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Rössle-Str. 10, 13125 Berlin, Germany
| | - Max T. Lucht
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Rössle-Str. 10, 13125 Berlin, Germany
| | - Astrid Petzoldt
- Department of Biology, Chemistry, Pharmacy, Freie Universität Berlin, 14195 Berlin, Germany
| | - Shuhan Kong
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Rössle-Str. 10, 13125 Berlin, Germany
| | - Jiachen Sun
- Department of Chemistry, University of Illinois Chicago, Chicago, IL 60607, USA
| | - James H. Vines
- School of Biosciences, University of Sheffield, Firth Court Western Bank, Sheffield S10 2TN, UK
| | - Narasimha Swamy Telugu
- Max-Delbrück-Centrum für Molekulare Medizin (MDC), Technology Platform Pluripotent Stem Cells, Robert-Rössle-Straße 10, 13125 Berlin, Germany
| | - Sebastian Diecke
- Max-Delbrück-Centrum für Molekulare Medizin (MDC), Technology Platform Pluripotent Stem Cells, Robert-Rössle-Straße 10, 13125 Berlin, Germany
| | - Thomas Kaas
- Leipzig University, Carl-Ludwig-Institute of Physiology, Faculty of Medicine, 04103 Leipzig, Germany
| | - Torsten Bullmann
- Leipzig University, Carl-Ludwig-Institute of Physiology, Faculty of Medicine, 04103 Leipzig, Germany
| | - Christopher Schmied
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Rössle-Str. 10, 13125 Berlin, Germany
| | - Delia Löwe
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Rössle-Str. 10, 13125 Berlin, Germany
| | - Jason S. King
- School of Biosciences, University of Sheffield, Firth Court Western Bank, Sheffield S10 2TN, UK
| | - Wonhwa Cho
- Department of Chemistry, University of Illinois Chicago, Chicago, IL 60607, USA
| | - Stefan Hallermann
- Leipzig University, Carl-Ludwig-Institute of Physiology, Faculty of Medicine, 04103 Leipzig, Germany
| | - Dmytro Puchkov
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Rössle-Str. 10, 13125 Berlin, Germany
| | - Stephan J. Sigrist
- Department of Biology, Chemistry, Pharmacy, Freie Universität Berlin, 14195 Berlin, Germany
| | - Volker Haucke
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Rössle-Str. 10, 13125 Berlin, Germany
- Department of Biology, Chemistry, Pharmacy, Freie Universität Berlin, 14195 Berlin, Germany
- Charité – Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
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9
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Urrutia PJ, Bórquez DA. Expanded bioinformatic analysis of Oximouse dataset reveals key putative processes involved in brain aging and cognitive decline. Free Radic Biol Med 2023; 207:200-211. [PMID: 37473875 DOI: 10.1016/j.freeradbiomed.2023.07.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 07/11/2023] [Accepted: 07/17/2023] [Indexed: 07/22/2023]
Abstract
The theory that aging is driven by the damage produced by reactive oxygen species (ROS) derived from oxidative metabolism dominated geroscience studies during the second half of the 20th century. However, increasing evidence that ROS also plays a key role in the physiological regulation of numerous processes through the reversible oxidation of cysteine residues in proteins, has challenged this notion. Currently, the scope of redox signaling has reached proteomic dimensions through mass spectrometry techniques. Here, we perform a comprehensive bioinformatics analysis of cysteine oxidation changes during mouse brain aging, using the quantitative data provided in the Oximouse dataset. Interestingly, our unbiased analysis identified hundreds of putative cysteine redox switches covering several pathways previously associated with aging. These include the ubiquitin-proteasome pathway and one-carbon metabolism (folate cycle, methionine cycle, transsulfuration and polyamine pathways). Surprisingly, cysteine oxidation changes are enriched in synaptic proteins in a highly asymmetric distribution: while postsynaptic proteins tend to increase cysteine oxidation with age, the opposite occurs for presynaptic proteins. Additionally, cysteine oxidation changes during aging are associated with proteins involved in the regulation of the mitochondrial transition pore opening and synaptic calcium homeostasis. Our analysis reinforces the concept that brain aging is associated with selective changes in the oxidation state of key proteins, rather than an overall trend toward increased oxidation. Also, we provide a prioritized list of specific cysteine residues with putative impact in aging processes for future experimental validation.
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Affiliation(s)
- Pamela J Urrutia
- Institute for Nutrition & Food Technology (INTA), Universidad de Chile, El Líbano 5524, Santiago, 7830490, Chile; Geroscience Center for Brain Health and Metabolism, Santiago, 7800003, Chile
| | - Daniel A Bórquez
- Laboratory of Cell Signaling & Bioinformatics, Center for Biomedical Research, Faculty of Medicine, Universidad Diego Portales, Ejército Libertador 141, Santiago, 8370007, Chile.
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10
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Xu H, Oses-Prieto JA, Khvotchev M, Jain S, Liang J, Burlingame A, Edwards RH. Adaptor protein AP-3 produces synaptic vesicles that release at high frequency by recruiting phospholipid flippase ATP8A1. Nat Neurosci 2023; 26:1685-1700. [PMID: 37723322 DOI: 10.1038/s41593-023-01434-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Accepted: 08/14/2023] [Indexed: 09/20/2023]
Abstract
Neural systems encode information in the frequency of action potentials, which is then decoded by synaptic transmission. However, the rapid, synchronous release of neurotransmitters depletes synaptic vesicles (SVs), limiting release at high firing rates. How then do synapses convey information about frequency? Here, we show in mouse hippocampal neurons and slices that the adaptor protein AP-3 makes a subset of SVs that respond specifically to high-frequency stimulation. Neurotransmitter transporters slot onto these SVs in different proportions, contributing to the distinct properties of release observed at different excitatory synapses. Proteomics reveals that AP-3 targets the phospholipid flippase ATP8A1 to SVs; loss of ATP8A1 recapitulates the defect in SV mobilization at high frequency observed with loss of AP-3. The mechanism involves recruitment of synapsin by the cytoplasmically oriented phosphatidylserine translocated by ATP8A1. Thus, ATP8A1 enables the subset of SVs made by AP-3 to release at high frequency.
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Affiliation(s)
- Hongfei Xu
- Departments of Physiology and Neurology, University of California, San Francisco School of Medicine, San Francisco, CA, USA
| | - Juan A Oses-Prieto
- Department of Pharmaceutical Chemistry, University of California, San Francisco School of Medicine, San Francisco, CA, USA
| | - Mikhail Khvotchev
- Departments of Physiology and Neurology, University of California, San Francisco School of Medicine, San Francisco, CA, USA
- Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Shweta Jain
- Departments of Physiology and Neurology, University of California, San Francisco School of Medicine, San Francisco, CA, USA
| | - Jocelyn Liang
- Departments of Physiology and Neurology, University of California, San Francisco School of Medicine, San Francisco, CA, USA
| | - Alma Burlingame
- Department of Pharmaceutical Chemistry, University of California, San Francisco School of Medicine, San Francisco, CA, USA
| | - Robert H Edwards
- Departments of Physiology and Neurology, University of California, San Francisco School of Medicine, San Francisco, CA, USA.
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11
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Georgiev SV, Rizzoli SO. The long-loop recycling (LLR) of synaptic components as a question of economics. Mol Cell Neurosci 2023; 126:103862. [PMID: 37236414 DOI: 10.1016/j.mcn.2023.103862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 05/15/2023] [Accepted: 05/19/2023] [Indexed: 05/28/2023] Open
Abstract
The pre- and post-synaptic compartments contain a variety of molecules that are known to recycle between the plasma membrane and intracellular organelles. The recycling steps have been amply described in functional terms, with, for example, synaptic vesicle recycling being essential for neurotransmitter release, and postsynaptic receptor recycling being a fundamental feature of synaptic plasticity. However, synaptic protein recycling may also serve a more prosaic role, simply ensuring the repeated use of specific components, thereby minimizing the energy expenditure on the synthesis of synaptic proteins. This type of process has been recently described for components of the extracellular matrix, which undergo long-loop recycling (LLR), to and from the cell body. Here we suggest that the energy-saving recycling of synaptic components may be more widespread than is generally acknowledged, potentially playing a role in both synaptic vesicle protein usage and postsynaptic receptor metabolism.
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Affiliation(s)
- Svilen Veselinov Georgiev
- University Medical Center Göttingen, Institute for Neuro- and Sensory Physiology, Germany; International Max Planck Research School for Neuroscience, Göttingen, Germany.
| | - Silvio O Rizzoli
- University Medical Center Göttingen, Institute for Neuro- and Sensory Physiology, Germany; Biostructural Imaging of Neurodegeneration (BIN) Center, Göttingen, Germany; Excellence Cluster Multiscale Bioimaging, Göttingen, Germany.
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12
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Downs M, Zaia J, Sethi MK. Mass spectrometry methods for analysis of extracellular matrix components in neurological diseases. MASS SPECTROMETRY REVIEWS 2023; 42:1848-1875. [PMID: 35719114 PMCID: PMC9763553 DOI: 10.1002/mas.21792] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 04/12/2022] [Accepted: 05/24/2022] [Indexed: 06/15/2023]
Abstract
The brain extracellular matrix (ECM) is a highly glycosylated environment and plays important roles in many processes including cell communication, growth factor binding, and scaffolding. The formation of structures such as perineuronal nets (PNNs) is critical in neuroprotection and neural plasticity, and the formation of molecular networks is dependent in part on glycans. The ECM is also implicated in the neuropathophysiology of disorders such as Alzheimer's disease (AD), Parkinson's disease (PD), and Schizophrenia (SZ). As such, it is of interest to understand both the proteomic and glycomic makeup of healthy and diseased brain ECM. Further, there is a growing need for site-specific glycoproteomic information. Over the past decade, sample preparation, mass spectrometry, and bioinformatic methods have been developed and refined to provide comprehensive information about the glycoproteome. Core ECM molecules including versican, hyaluronan and proteoglycan link proteins, and tenascin are dysregulated in AD, PD, and SZ. Glycomic changes such as differential sialylation, sulfation, and branching are also associated with neurodegeneration. A more thorough understanding of the ECM and its proteomic, glycomic, and glycoproteomic changes in brain diseases may provide pathways to new therapeutic options.
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Affiliation(s)
- Margaret Downs
- Department of Biochemistry, Center for Biomedical Mass Spectrometry, Boston University, Boston, Massachusetts, USA
| | - Joseph Zaia
- Department of Biochemistry, Center for Biomedical Mass Spectrometry, Boston University, Boston, Massachusetts, USA
- Bioinformatics Program, Boston University, Boston, Massachusetts, USA
| | - Manveen K Sethi
- Department of Biochemistry, Center for Biomedical Mass Spectrometry, Boston University, Boston, Massachusetts, USA
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13
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Wang Q, Wang X, Yang T, Yang L, Liu H, Zheng Y, Jiang G, Liu H, Huang C, Chen J, Wang Z, Wang Z, Zhao W, Lin J, Zhang X, Shi J, Han K, Le X, Ren Y, Li Y, Hong Y, Shi W, Cui D, Qian M, Xu J, Zheng X, Gao Y, Li C, Lin J, Huang Z, Wu H. A common variant in AAK1 reduces risk of noise-induced hearing loss. Natl Sci Rev 2023; 10:nwad080. [PMID: 37547059 PMCID: PMC10401317 DOI: 10.1093/nsr/nwad080] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 03/14/2023] [Accepted: 03/17/2023] [Indexed: 08/08/2023] Open
Affiliation(s)
| | | | - Tao Yang
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
- Ear Institute, Shanghai Jiao Tong University School of Medicine, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, China
| | - Lu Yang
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
- Ear Institute, Shanghai Jiao Tong University School of Medicine, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, China
| | - Huihui Liu
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
- Ear Institute, Shanghai Jiao Tong University School of Medicine, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, China
| | - Yihang Zheng
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
- Ear Institute, Shanghai Jiao Tong University School of Medicine, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, China
| | - Guixian Jiang
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
- Ear Institute, Shanghai Jiao Tong University School of Medicine, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, China
| | - Hongchao Liu
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
- Ear Institute, Shanghai Jiao Tong University School of Medicine, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, China
| | - Chenhui Huang
- Shanghai Institute of Precision Medicine, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
| | - Juan Chen
- Shanghai Institute of Precision Medicine, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
| | - Zhentao Wang
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
- Ear Institute, Shanghai Jiao Tong University School of Medicine, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, China
| | - Zhaoyan Wang
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
- Ear Institute, Shanghai Jiao Tong University School of Medicine, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, China
| | - Wei Zhao
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
- Ear Institute, Shanghai Jiao Tong University School of Medicine, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, China
| | - Jiannan Lin
- The Core Laboratory in the Medical Center of Clinical Research, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
| | - Xuejie Zhang
- Biobank, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
| | - Junbo Shi
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
- Ear Institute, Shanghai Jiao Tong University School of Medicine, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, China
| | - Kun Han
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
- Ear Institute, Shanghai Jiao Tong University School of Medicine, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, China
| | - Xingyu Le
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
- Ear Institute, Shanghai Jiao Tong University School of Medicine, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, China
| | - Yan Ren
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
- Ear Institute, Shanghai Jiao Tong University School of Medicine, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, China
| | - Yun Li
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
- Ear Institute, Shanghai Jiao Tong University School of Medicine, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, China
| | - Yingying Hong
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
- Ear Institute, Shanghai Jiao Tong University School of Medicine, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, China
| | - Wentao Shi
- Clinical Research Center, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
| | - Dongqi Cui
- Clinical Research Center, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
| | - Minfei Qian
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
- Ear Institute, Shanghai Jiao Tong University School of Medicine, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, China
| | - Jun Xu
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
- Ear Institute, Shanghai Jiao Tong University School of Medicine, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, China
| | - Xiaofei Zheng
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
- Ear Institute, Shanghai Jiao Tong University School of Medicine, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, China
| | - Yunge Gao
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
- Ear Institute, Shanghai Jiao Tong University School of Medicine, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, China
| | - Chen Li
- Network and Information Center, Shanghai Jiao Tong University, China
| | - James Lin
- Network and Information Center, Shanghai Jiao Tong University, China
| | | | - Hao Wu
- Corresponding authors. E-mail:
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14
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Stephens AD, Villegas AF, Chung CW, Vanderpoorten O, Pinotsi D, Mela I, Ward E, McCoy TM, Cubitt R, Routh AF, Kaminski CF, Kaminski Schierle GS. α-Synuclein fibril and synaptic vesicle interactions lead to vesicle destruction and increased lipid-associated fibril uptake into iPSC-derived neurons. Commun Biol 2023; 6:526. [PMID: 37188797 PMCID: PMC10185682 DOI: 10.1038/s42003-023-04884-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Accepted: 04/27/2023] [Indexed: 05/17/2023] Open
Abstract
Monomeric alpha-synuclein (aSyn) is a well characterised protein that importantly binds to lipids. aSyn monomers assemble into amyloid fibrils which are localised to lipids and organelles in insoluble structures found in Parkinson's disease patient's brains. Previous work to address pathological aSyn-lipid interactions has focused on using synthetic lipid membranes, which lack the complexity of physiological lipid membranes. Here, we use physiological membranes in the form of synaptic vesicles (SV) isolated from rodent brain to demonstrate that lipid-associated aSyn fibrils are more easily taken up into iPSC-derived cortical i3Neurons. Lipid-associated aSyn fibril characterisation reveals that SV lipids are an integrated part of the fibrils and while their fibril morphology differs from aSyn fibrils alone, the core fibril structure remains the same, suggesting the lipids lead to the increase in fibril uptake. Furthermore, SV enhance the aggregation rate of aSyn, yet increasing the SV:aSyn ratio causes a reduction in aggregation propensity. We finally show that aSyn fibrils disintegrate SV, whereas aSyn monomers cause clustering of SV using small angle neutron scattering and high-resolution imaging. Disease burden on neurons may be impacted by an increased uptake of lipid-associated aSyn which could enhance stress and pathology, which in turn may have fatal consequences for neurons.
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Affiliation(s)
- Amberley D Stephens
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK.
| | - Ana Fernandez Villegas
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK
| | - Chyi Wei Chung
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK
- Department of Physics, Kavli Institute for Nanoscience Discovery, University of Oxford, Oxford, UK
| | - Oliver Vanderpoorten
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK
- Department of Physics and Technology, UiT The Arctic University of Norway, Tromsø, Norway
| | - Dorothea Pinotsi
- Scientific Center for Optical and Electron Microscopy, ETH Zürich, Zürich, Switzerland
| | - Ioanna Mela
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - Edward Ward
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK
| | - Thomas M McCoy
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK
| | | | - Alexander F Routh
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK
| | - Clemens F Kaminski
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK
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15
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Kolen B, Borghans B, Kortzak D, Lugo V, Hannack C, Guzman RE, Ullah G, Fahlke C. Vesicular glutamate transporters are H +-anion exchangers that operate at variable stoichiometry. Nat Commun 2023; 14:2723. [PMID: 37169755 PMCID: PMC10175566 DOI: 10.1038/s41467-023-38340-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 04/26/2023] [Indexed: 05/13/2023] Open
Abstract
Vesicular glutamate transporters accumulate glutamate in synaptic vesicles, where they also function as a major Cl- efflux pathway. Here we combine heterologous expression and cellular electrophysiology with mathematical modeling to understand the mechanisms underlying this dual function of rat VGLUT1. When glutamate is the main cytoplasmic anion, VGLUT1 functions as H+-glutamate exchanger, with a transport rate of around 600 s-1 at -160 mV. Transport of other large anions, including aspartate, is not stoichiometrically coupled to H+ transport, and Cl- permeates VGLUT1 through an aqueous anion channel with unitary transport rates of 1.5 × 105 s-1 at -160 mV. Mathematical modeling reveals that H+ coupling is sufficient for selective glutamate accumulation in model vesicles and that VGLUT Cl- channel function increases the transport efficiency by accelerating glutamate accumulation and reducing ATP-driven H+ transport. In summary, we provide evidence that VGLUT1 functions as H+-glutamate exchanger that is partially or fully uncoupled by other anions.
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Affiliation(s)
- Bettina Kolen
- Institute of Biological Information Processing, Molekular- und Zellphysiologie (IBI-1), Forschungszentrum Jülich, 52428, Jülich, Germany
| | - Bart Borghans
- Institute of Biological Information Processing, Molekular- und Zellphysiologie (IBI-1), Forschungszentrum Jülich, 52428, Jülich, Germany
| | - Daniel Kortzak
- Institute of Biological Information Processing, Molekular- und Zellphysiologie (IBI-1), Forschungszentrum Jülich, 52428, Jülich, Germany
| | - Victor Lugo
- Institute of Biological Information Processing, Molekular- und Zellphysiologie (IBI-1), Forschungszentrum Jülich, 52428, Jülich, Germany
| | - Cora Hannack
- Institute of Biological Information Processing, Molekular- und Zellphysiologie (IBI-1), Forschungszentrum Jülich, 52428, Jülich, Germany
| | - Raul E Guzman
- Institute of Biological Information Processing, Molekular- und Zellphysiologie (IBI-1), Forschungszentrum Jülich, 52428, Jülich, Germany
| | - Ghanim Ullah
- Department of Physics, University of South Florida, Tampa, FL, 33620, USA
| | - Christoph Fahlke
- Institute of Biological Information Processing, Molekular- und Zellphysiologie (IBI-1), Forschungszentrum Jülich, 52428, Jülich, Germany.
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16
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Bradberry MM, Peters-Clarke TM, Shishkova E, Chapman ER, Coon JJ. N-glycoproteomics of brain synapses and synaptic vesicles. Cell Rep 2023; 42:112368. [PMID: 37036808 PMCID: PMC10560701 DOI: 10.1016/j.celrep.2023.112368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 01/13/2023] [Accepted: 03/23/2023] [Indexed: 04/11/2023] Open
Abstract
At mammalian neuronal synapses, synaptic vesicle (SV) glycoproteins are essential for robust neurotransmission. Asparagine (N)-linked glycosylation is required for delivery of the major SV glycoproteins synaptophysin and SV2A to SVs. Despite this key role for N-glycosylation, the molecular compositions of SV N-glycans are largely unknown. In this study, we combined organelle isolation techniques and high-resolution mass spectrometry to characterize N-glycosylation at synapses and SVs from mouse brain. Detecting over 2,500 unique glycopeptides, we found that SVs harbor a distinct population of oligomannose and highly fucosylated N-glycans. Using complementary fluorescence methods, we identify at least one highly fucosylated N-glycan enriched in SVs compared with synaptosomes. High fucosylation was characteristic of SV proteins, plasma membrane proteins, and cell adhesion molecules with key roles in synaptic function and development. Our results define the N-glycoproteome of a specialized neuronal organelle and inform timely questions in the glycobiology of synaptic pruning and neuroinflammation.
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Affiliation(s)
- Mazdak M Bradberry
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA; Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA; National Center for Quantitative Biology of Complex Systems, Madison, WI 53706, USA; Howard Hughes Medical Institute and Department of Neuroscience, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA; Department of Psychiatry, Columbia University, New York, NY 10032, USA.
| | - Trenton M Peters-Clarke
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA; Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA; National Center for Quantitative Biology of Complex Systems, Madison, WI 53706, USA
| | - Evgenia Shishkova
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA; Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA; National Center for Quantitative Biology of Complex Systems, Madison, WI 53706, USA
| | - Edwin R Chapman
- Howard Hughes Medical Institute and Department of Neuroscience, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
| | - Joshua J Coon
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA; Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA; National Center for Quantitative Biology of Complex Systems, Madison, WI 53706, USA; Morgridge Institute for Research, Madison, WI 53715, USA
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17
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Dugan MP, Ferguson LB, Hertz NT, Chalkley RJ, Burlingame AL, Shokat KM, Parker PJ, Messing RO. Chemical Genetic Identification of PKC Epsilon Substrates in Mouse Brain. Mol Cell Proteomics 2023; 22:100522. [PMID: 36863607 PMCID: PMC10105488 DOI: 10.1016/j.mcpro.2023.100522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 01/25/2023] [Accepted: 02/27/2023] [Indexed: 03/04/2023] Open
Abstract
PKC epsilon (PKCε) plays important roles in behavioral responses to alcohol and in anxiety-like behavior in rodents, making it a potential drug target for reducing alcohol consumption and anxiety. Identifying signals downstream of PKCε could reveal additional targets and strategies for interfering with PKCε signaling. We used a chemical genetic screen combined with mass spectrometry to identify direct substrates of PKCε in mouse brain and validated findings for 39 of them using peptide arrays and in vitro kinase assays. Prioritizing substrates with several public databases such as LINCS-L1000, STRING, GeneFriends, and GeneMAINA predicted interactions between these putative substrates and PKCε and identified substrates associated with alcohol-related behaviors, actions of benzodiazepines, and chronic stress. The 39 substrates could be broadly classified in three functional categories: cytoskeletal regulation, morphogenesis, and synaptic function. These results provide a list of brain PKCε substrates, many of which are novel, for future investigation to determine the role of PKCε signaling in alcohol responses, anxiety, responses to stress, and other related behaviors.
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Affiliation(s)
- Michael P Dugan
- Department of Neuroscience, The University of Texas at Austin, Austin, Texas, USA
| | - Laura B Ferguson
- Department of Neuroscience, The University of Texas at Austin, Austin, Texas, USA
| | - Nicholas T Hertz
- Department of Cellular and Molecular Pharmacology and Howard Hughes Medical Institute at the University of California San Francisco, San Francisco, California, USA; Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, California, USA
| | - Robert J Chalkley
- Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, California, USA
| | - Alma L Burlingame
- Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, California, USA
| | - Kevan M Shokat
- Department of Cellular and Molecular Pharmacology and Howard Hughes Medical Institute at the University of California San Francisco, San Francisco, California, USA
| | - Peter J Parker
- The Francis Crick Institute, London, United Kingdom; School of Cancer and Pharmaceutical Sciences, King's College London, London, United Kingdom
| | - Robert O Messing
- Department of Neuroscience, The University of Texas at Austin, Austin, Texas, USA.
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18
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Xuan Z, Yang S, Clark B, Hill SE, Manning L, Colón-Ramos DA. The active zone protein Clarinet regulates synaptic sorting of ATG-9 and presynaptic autophagy. PLoS Biol 2023; 21:e3002030. [PMID: 37053235 PMCID: PMC10101500 DOI: 10.1371/journal.pbio.3002030] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 02/08/2023] [Indexed: 04/14/2023] Open
Abstract
Autophagy is essential for cellular homeostasis and function. In neurons, autophagosome biogenesis is temporally and spatially regulated to occur near presynaptic sites, in part via the trafficking of autophagy transmembrane protein ATG-9. The molecules that regulate autophagy by sorting ATG-9 at synapses remain largely unknown. Here, we conduct forward genetic screens at single synapses of C. elegans neurons and identify a role for the long isoform of the active zone protein Clarinet (CLA-1L) in regulating sorting of autophagy protein ATG-9 at synapses, and presynaptic autophagy. We determine that disrupting CLA-1L results in abnormal accumulation of ATG-9 containing vesicles enriched with clathrin. The ATG-9 phenotype in cla-1(L) mutants is not observed for other synaptic vesicle proteins, suggesting distinct mechanisms that regulate sorting of ATG-9-containing vesicles and synaptic vesicles. Through genetic analyses, we uncover the adaptor protein complexes that genetically interact with CLA-1 in ATG-9 sorting. We also determine that CLA-1L extends from the active zone to the periactive zone and genetically interacts with periactive zone proteins in ATG-9 sorting. Our findings reveal novel roles for active zone proteins in the sorting of ATG-9 and in presynaptic autophagy.
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Affiliation(s)
- Zhao Xuan
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Neuroscience and Cell Biology, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Sisi Yang
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Neuroscience and Cell Biology, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Benjamin Clark
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Neuroscience and Cell Biology, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Sarah E. Hill
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Neuroscience and Cell Biology, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Laura Manning
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Neuroscience and Cell Biology, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Daniel A. Colón-Ramos
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Neuroscience and Cell Biology, Yale University School of Medicine, New Haven, Connecticut, United States of America
- Instituto de Neurobiología, Recinto de Ciencias Médicas, Universidad de Puerto Rico, San Juan,Puerto Rico
- Wu Tsai Institute, Yale University, New Haven, Connecticut, United States of America
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19
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Vidyadhara DJ, Somayaji M, Wade N, Yücel B, Zhao H, Shashaank N, Ribaudo J, Gupta J, Lam TT, Sames D, Greene LE, Sulzer DL, Chandra SS. Dopamine transporter and synaptic vesicle sorting defects underlie auxilin-associated Parkinson's disease. Cell Rep 2023; 42:112231. [PMID: 36920906 PMCID: PMC10127800 DOI: 10.1016/j.celrep.2023.112231] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 12/22/2022] [Accepted: 02/22/2023] [Indexed: 03/16/2023] Open
Abstract
Auxilin participates in the uncoating of clathrin-coated vesicles (CCVs), thereby facilitating synaptic vesicle (SV) regeneration at presynaptic sites. Auxilin (DNAJC6/PARK19) loss-of-function mutations cause early-onset Parkinson's disease (PD). Here, we utilized auxilin knockout (KO) mice to elucidate the mechanisms through which auxilin deficiency and clathrin-uncoating deficits lead to PD. Auxilin KO mice display cardinal features of PD, including progressive motor deficits, α-synuclein pathology, nigral dopaminergic loss, and neuroinflammation. Significantly, treatment with L-DOPA ameliorated motor deficits. Unbiased proteomic and neurochemical analyses of auxilin KO brains indicated dopamine dyshomeostasis. We validated these findings by demonstrating slower dopamine reuptake kinetics in vivo, an effect associated with dopamine transporter misrouting into axonal membrane deformities in the dorsal striatum. Defective SV protein sorting and elevated synaptic autophagy also contribute to ineffective dopamine sequestration and compartmentalization, ultimately leading to neurodegeneration. This study provides insights into how presynaptic endocytosis deficits lead to dopaminergic vulnerability and pathogenesis of PD.
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Affiliation(s)
- D J Vidyadhara
- Department of Neurology, Yale University, New Haven, CT, USA; Department of Neuroscience, Yale University, New Haven, CT, USA
| | - Mahalakshmi Somayaji
- Department of Psychiatry, Columbia University, New York, NY, USA; Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, USA
| | - Nigel Wade
- Department of Neurology, Yale University, New Haven, CT, USA; Department of Neuroscience, Yale University, New Haven, CT, USA
| | - Betül Yücel
- Department of Neurology, Yale University, New Haven, CT, USA; Department of Neuroscience, Yale University, New Haven, CT, USA
| | - Helen Zhao
- Department of Neurology, Yale University, New Haven, CT, USA
| | - N Shashaank
- Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, USA; Department of Computer Science, Columbia University, New York, NY, USA; New York Genome Center, New York, NY, USA
| | - Joseph Ribaudo
- Department of Neurology, Yale University, New Haven, CT, USA
| | - Jyoti Gupta
- Department of Neuroscience, Yale University, New Haven, CT, USA
| | - TuKiet T Lam
- Keck MS and Proteomics Resource, Departments of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Dalibor Sames
- Department of Chemistry and NeuroTechnology Center, Columbia University, New York, NY, USA
| | - Lois E Greene
- Laboratory of Cell Biology, NHLBI, National Institutes of Health, Bethesda, MD, USA
| | - David L Sulzer
- Department of Psychiatry, Columbia University, New York, NY, USA; Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, USA; Departments of Neurology and Pharmacology, Columbia University, New York, NY, USA; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD, USA
| | - Sreeganga S Chandra
- Department of Neurology, Yale University, New Haven, CT, USA; Department of Neuroscience, Yale University, New Haven, CT, USA; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD, USA; Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University, New Haven, CT, USA.
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20
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Eagleson KL, Levitt P. Alterations in the Proteome of Developing Neocortical Synaptosomes in the Absence of MET Signaling Revealed by Comparative Proteomics. Dev Neurosci 2023; 45:126-138. [PMID: 36882009 PMCID: PMC10239366 DOI: 10.1159/000529981] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Accepted: 02/28/2023] [Indexed: 03/09/2023] Open
Abstract
Alterations in the expression of genes encoding proteins involved in synapse formation, maturation, and function are a hallmark of many neurodevelopmental and psychiatric disorders. For example, there is reduced neocortical expression of the MET receptor tyrosine kinase (MET) transcript and protein in Autism Spectrum Disorder (ASD) and Rett syndrome. Preclinical in vivo and in vitro models manipulating MET signaling reveal that the receptor modulates excitatory synapse development and maturation in select forebrain circuits. The molecular adaptations underlying the altered synaptic development remain unknown. We performed a comparative mass spectrometry analysis of synaptosomes generated from the neocortex of wild type and Met null mice during the peak of synaptogenesis (postnatal day 14; data are available from ProteomeXchange with identifier PXD033204). The analyses revealed broad disruption of the developing synaptic proteome in the absence of MET, consistent with the localization of MET protein in pre- and postsynaptic compartments, including proteins associated with the neocortical synaptic MET interactome and those encoded by syndromic and ASD risk genes. In addition to an overrepresentation of altered proteins associated with the SNARE complex, multiple proteins in the ubiquitin-proteasome system and associated with the synaptic vesicle, as well as proteins that regulate actin filament organization and synaptic vesicle exocytosis/endocytosis, were disrupted. Taken together, the proteomic changes are consistent with structural and functional changes observed following alterations in MET signaling. We hypothesize that the molecular adaptations following Met deletion may reflect a general mechanism that produces circuit-specific molecular changes due to loss or reduction of synaptic signaling proteins.
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Affiliation(s)
- Kathie L Eagleson
- Department of Pediatrics and Neurogenetics Program, The Saban Research Institute, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
- Developmental Neuroscience and Neurogenetics Program, The Saban Research Institute, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Pat Levitt
- Department of Pediatrics and Neurogenetics Program, The Saban Research Institute, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, California, USA,
- Developmental Neuroscience and Neurogenetics Program, The Saban Research Institute, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, California, USA,
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21
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Synaptotagmin 9 Modulates Spontaneous Neurotransmitter Release in Striatal Neurons by Regulating Substance P Secretion. J Neurosci 2023; 43:1475-1491. [PMID: 36732068 PMCID: PMC9992334 DOI: 10.1523/jneurosci.1857-22.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 01/05/2023] [Accepted: 01/10/2023] [Indexed: 02/04/2023] Open
Abstract
Synaptotagmin 9 (SYT9) is a tandem C2 domain Ca2+ sensor for exocytosis in neuroendocrine cells; its function in neurons remains unclear. Here, we show that, in mixed-sex cultures, SYT9 does not trigger rapid synaptic vesicle exocytosis in mouse cortical, hippocampal, or striatal neurons, unless it is massively overexpressed. In striatal neurons, loss of SYT9 reduced the frequency of spontaneous neurotransmitter release events (minis). We delved into the underlying mechanism and discovered that SYT9 was localized to dense-core vesicles that contain substance P (SP). Loss of SYT9 impaired SP release, causing the observed decrease in mini frequency. This model is further supported by loss of function mutants. Namely, Ca2+ binding to the C2A domain of SYT9 triggered membrane fusion in vitro, and mutations that disrupted this activity abolished the ability of SYT9 to regulate both SP release and mini frequency. We conclude that SYT9 indirectly regulates synaptic transmission in striatal neurons by controlling SP release.SIGNIFICANCE STATEMENT Synaptotagmin 9 (SYT9) has been described as a Ca2+ sensor for dense-core vesicle (DCV) exocytosis in neuroendocrine cells, but its role in neurons remains unclear, despite widespread expression in the brain. This article examines the role of SYT9 in synaptic transmission across cultured cortical, hippocampal, and striatal neuronal preparations. We found that SYT9 regulates spontaneous neurotransmitter release in striatal neurons by serving as a Ca2+ sensor for the release of the neuromodulator substance P from DCVs. This demonstrates a novel role for SYT9 in neurons and uncovers a new field of study into neuromodulation by SYT9, a protein that is widely expressed in the brain.
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22
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Synaptic vesicle proteins and ATG9A self-organize in distinct vesicle phases within synapsin condensates. Nat Commun 2023; 14:455. [PMID: 36709207 PMCID: PMC9884207 DOI: 10.1038/s41467-023-36081-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Accepted: 01/16/2023] [Indexed: 01/30/2023] Open
Abstract
Ectopic expression in fibroblasts of synapsin 1 and synaptophysin is sufficient to generate condensates of vesicles highly reminiscent of synaptic vesicle (SV) clusters and with liquid-like properties. Here we show that unlike synaptophysin, other major integral SV membrane proteins fail to form condensates with synapsin, but co-assemble into the clusters formed by synaptophysin and synapsin in this ectopic expression system. Another vesicle membrane protein, ATG9A, undergoes activity-dependent exo-endocytosis at synapses, raising questions about the relation of ATG9A traffic to the traffic of SVs. We find that both in fibroblasts and in nerve terminals ATG9A does not co-assemble into synaptophysin-positive vesicle condensates but localizes on a distinct class of vesicles that also assembles with synapsin but into a distinct phase. Our findings suggest that ATG9A undergoes differential sorting relative to SV proteins and also point to a dual role of synapsin in controlling clustering at synapses of SVs and ATG9A vesicles.
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23
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Gao V, Briano JA, Komer LE, Burré J. Functional and Pathological Effects of α-Synuclein on Synaptic SNARE Complexes. J Mol Biol 2023; 435:167714. [PMID: 35787839 PMCID: PMC10472340 DOI: 10.1016/j.jmb.2022.167714] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Revised: 06/24/2022] [Accepted: 06/27/2022] [Indexed: 02/07/2023]
Abstract
α-Synuclein is an abundant protein at the neuronal synapse that has been implicated in Parkinson's disease for over 25 years and characterizes the hallmark pathology of a group of neurodegenerative diseases now known as the synucleinopathies. Physiologically, α-synuclein exists in an equilibrium between a synaptic vesicle membrane-bound α-helical multimer and a cytosolic largely unstructured monomer. Through its membrane-bound state, α-synuclein functions in neurotransmitter release by modulating several steps in the synaptic vesicle cycle, including synaptic vesicle clustering and docking, SNARE complex assembly, and homeostasis of synaptic vesicle pools. These functions have been ascribed to α-synuclein's interactions with the synaptic vesicle SNARE protein VAMP2/synaptobrevin-2, the synaptic vesicle-attached synapsins, and the synaptic vesicle membrane itself. How α-synuclein affects these processes, and whether disease is due to loss-of-function or gain-of-toxic-function of α-synuclein remains unclear. In this review, we provide an in-depth summary of the existing literature, discuss possible reasons for the discrepancies in the field, and propose a working model that reconciles the findings in the literature.
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Affiliation(s)
- Virginia Gao
- Appel Alzheimer's Disease Research Institute & Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA; Department of Neurology, New York Presbyterian/Weill Cornell Medicine, New York, NY, USA.
| | - Juan A Briano
- Appel Alzheimer's Disease Research Institute & Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Lauren E Komer
- Appel Alzheimer's Disease Research Institute & Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA. https://www.twitter.com/lauren_komer
| | - Jacqueline Burré
- Appel Alzheimer's Disease Research Institute & Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA.
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24
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Bhatt IS, Wilson N, Dias R, Torkamani A. A genome-wide association study of tinnitus reveals shared genetic links to neuropsychiatric disorders. Sci Rep 2022; 12:22511. [PMID: 36581688 PMCID: PMC9800371 DOI: 10.1038/s41598-022-26413-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 12/14/2022] [Indexed: 12/30/2022] Open
Abstract
Tinnitus, a phantom perception of sound in the absence of any external sound source, is a prevalent health condition often accompanied by psychiatric comorbidities. Recent genome-wide association studies (GWAS) highlighted a polygenic nature of tinnitus susceptibility. A shared genetic component between tinnitus and psychiatric conditions remains elusive. Here we present a GWAS using the UK Biobank to investigate the genetic processes linked to tinnitus and tinnitus-related distress, followed by gene-set enrichment analyses. The UK Biobank sample comprised 132,438 individuals with tinnitus and genotype data. Among the study sample, 38,525 individuals reported tinnitus, and 26,889 participants mentioned they experienced tinnitus-related distress in daily living. The genome-wide association analyses were conducted on tinnitus and tinnitus-related distress. We conducted enrichment analyses using FUMA to further understand the genetic processes linked to tinnitus and tinnitus-related distress. A genome-wide significant locus (lead SNP: rs71595470) for tinnitus was obtained in the vicinity of GPM6A. Nineteen independent loci reached suggestive association with tinnitus. Fifteen independent loci reached suggestive association with tinnitus-related distress. The enrichment analysis revealed a shared genetic component between tinnitus and psychiatric traits, such as bipolar disorder, feeling worried, cognitive ability, fast beta electroencephalogram, and sensation seeking. Metabolic, cardiovascular, hematological, and pharmacological gene sets revealed a significant association with tinnitus. Anxiety and stress-related gene sets revealed a significant association with tinnitus-related distress. The GWAS signals for tinnitus were enriched in the hippocampus and cortex, and for tinnitus-related distress were enriched in the brain and spinal cord. This study provides novel insights into genetic processes associated with tinnitus and tinnitus-related distress and demonstrates a shared genetic component underlying tinnitus and psychiatric conditions. Further collaborative attempts are necessary to identify genetic components underlying the phenotypic heterogeneity in tinnitus and provide biological insight into the etiology.
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Affiliation(s)
- Ishan Sunilkumar Bhatt
- grid.214572.70000 0004 1936 8294Department of Communication Sciences & Disorders, University of Iowa, 250 Hawkins Dr, Iowa City, IA 52242 USA
| | - Nicholas Wilson
- Department of Integrative Structural and Computational Biology Scripps Science Institute, La Jolla, CA 92037 USA
| | - Raquel Dias
- grid.15276.370000 0004 1936 8091Department of Microbiology and Cell Science, University of Florida, Gainesville, FL 32608 USA
| | - Ali Torkamani
- Department of Integrative Structural and Computational Biology Scripps Science Institute, La Jolla, CA 92037 USA
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25
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Hu JH, Liu Y, Hoffman DA. Identification of Kv4.2 protein complex and modifications by tandem affinity purification-mass spectrometry in primary neurons. Front Cell Neurosci 2022; 16:1070305. [PMID: 36568885 PMCID: PMC9788671 DOI: 10.3389/fncel.2022.1070305] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 11/24/2022] [Indexed: 12/13/2022] Open
Abstract
Proteins usually form complexes to fulfill variable physiological functions. In neurons, communication relies on synapses where receptors, channels, and anchoring proteins form complexes to precisely control signal transduction, synaptic integration, and action potential firing. Although there are many published protocols to isolate protein complexes in cell lines, isolation in neurons has not been well established. Here we introduce a method that combines lentiviral protein expression with tandem affinity purification followed by mass-spectrometry (TAP-MS) to identify protein complexes in neurons. This protocol can also be used to identify post-translational modifications (PTMs) of synaptic proteins. We used the A-type voltage-gated K+ channel subunit Kv4.2 as the target protein. Kv4.2 is highly expressed in the hippocampus where it contributes to learning and memory through its regulation of neuronal excitability and synaptic plasticity. We tagged Kv4.2 with the calmodulin-binding-peptide (CBP) and streptavidin-binding-peptide (SBP) at its C-terminus and expressed it in neurons via lentivirus. Kv4.2 was purified by two-step TAP and samples were analyzed by MS. MS identified two prominently known Kv4.2 interacting proteins [dipeptidyl peptidase like (DPPs) and Kv channel-interacting proteins (KChIPs)] in addition to novel synaptic proteins including glutamate receptors, a calcium channel, and anchoring proteins. Co-immunoprecipitation and colocalization experiments validated the association of Kv4.2 with glutamate receptors. In addition to protein complex identification, we used TAP-MS to identify Kv4.2 phosphorylation sites. Several known and unknown phosphorylation sites were identified. These findings provide a novel path to identify protein-protein interactions and PTMs in neurons and shed light on mechanisms of neuronal signaling potentially involved in the pathology of neurological diseases.
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26
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Sun C, Schuman EM. Logistics of neuronal protein turnover: Numbers and mechanisms. Mol Cell Neurosci 2022; 123:103793. [PMID: 36396040 DOI: 10.1016/j.mcn.2022.103793] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 11/07/2022] [Accepted: 11/09/2022] [Indexed: 11/16/2022] Open
Abstract
Research in the past twenty years or so has revealed that neurons synthesize and degrade proteins at their synapses to enable synaptic proteome remodelling on demand and in real-time. Here we provide a quantitative overview of the decentralized neuronal protein-turnover logistics. We first analyse the huge neuronal protein turnover demand that arises from subcellular compartments outside the cell body, followed by an overview of key quantities and modulation strategies in neuronal protein turnover logistics. In the end, we briefly review recent progress in neuronal local protein synthesis and summarize diverse protein-degradation mechanisms that are found near synapses.
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Affiliation(s)
- Chao Sun
- Max Planck Institute for Brain Research, 60438 Frankfurt am Main, Germany
| | - Erin M Schuman
- Max Planck Institute for Brain Research, 60438 Frankfurt am Main, Germany.
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27
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Rusilowicz-Jones EV, Brazel AJ, Frigenti F, Urbé S, Clague MJ. Membrane compartmentalisation of the ubiquitin system. Semin Cell Dev Biol 2022; 132:171-184. [PMID: 34895815 DOI: 10.1016/j.semcdb.2021.11.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 11/12/2021] [Accepted: 11/15/2021] [Indexed: 12/15/2022]
Abstract
We now have a comprehensive inventory of ubiquitin system components. Understanding of any system also needs an appreciation of how components are organised together. Quantitative proteomics has provided us with a census of their relative populations in several model cell types. Here, by examining large scale unbiased data sets, we seek to identify and map those components, which principally reside on the major organelles of the endomembrane system. We present the consensus distribution of > 50 ubiquitin modifying enzymes, E2s, E3s and DUBs, that possess transmembrane domains. This analysis reveals that the ER and endosomal compartments have a diverse cast of resident E3s, whilst the Golgi and mitochondria operate with a more restricted palette. We describe key functions of ubiquitylation that are specific to each compartment and relate this to their signature complement of ubiquitin modifying components.
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Affiliation(s)
- Emma V Rusilowicz-Jones
- Dept. of Molecular Physiology and Cell Signaling, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 3BX, UK
| | - Ailbhe J Brazel
- Dept. of Molecular Physiology and Cell Signaling, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 3BX, UK; Department of Biology, Maynooth University, Maynooth W23 F2K6, Ireland
| | - Francesca Frigenti
- Dept. of Molecular Physiology and Cell Signaling, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 3BX, UK
| | - Sylvie Urbé
- Dept. of Molecular Physiology and Cell Signaling, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 3BX, UK.
| | - Michael J Clague
- Dept. of Molecular Physiology and Cell Signaling, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 3BX, UK.
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28
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Kosmidis E, Shuttle CG, Preobraschenski J, Ganzella M, Johnson PJ, Veshaguri S, Holmkvist J, Møller MP, Marantos O, Marcoline F, Grabe M, Pedersen JL, Jahn R, Stamou D. Regulation of the mammalian-brain V-ATPase through ultraslow mode-switching. Nature 2022; 611:827-834. [PMID: 36418452 PMCID: PMC11212661 DOI: 10.1038/s41586-022-05472-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 10/21/2022] [Indexed: 11/24/2022]
Abstract
Vacuolar-type adenosine triphosphatases (V-ATPases)1-3 are electrogenic rotary mechanoenzymes structurally related to F-type ATP synthases4,5. They hydrolyse ATP to establish electrochemical proton gradients for a plethora of cellular processes1,3. In neurons, the loading of all neurotransmitters into synaptic vesicles is energized by about one V-ATPase molecule per synaptic vesicle6,7. To shed light on this bona fide single-molecule biological process, we investigated electrogenic proton-pumping by single mammalian-brain V-ATPases in single synaptic vesicles. Here we show that V-ATPases do not pump continuously in time, as suggested by observing the rotation of bacterial homologues8 and assuming strict ATP-proton coupling. Instead, they stochastically switch between three ultralong-lived modes: proton-pumping, inactive and proton-leaky. Notably, direct observation of pumping revealed that physiologically relevant concentrations of ATP do not regulate the intrinsic pumping rate. ATP regulates V-ATPase activity through the switching probability of the proton-pumping mode. By contrast, electrochemical proton gradients regulate the pumping rate and the switching of the pumping and inactive modes. A direct consequence of mode-switching is all-or-none stochastic fluctuations in the electrochemical gradient of synaptic vesicles that would be expected to introduce stochasticity in proton-driven secondary active loading of neurotransmitters and may thus have important implications for neurotransmission. This work reveals and emphasizes the mechanistic and biological importance of ultraslow mode-switching.
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Affiliation(s)
- Eleftherios Kosmidis
- Center for Geometrically Engineered Cellular Membranes, Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
| | - Christopher G Shuttle
- Center for Geometrically Engineered Cellular Membranes, Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
| | - Julia Preobraschenski
- Laboratory of Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Institute for Auditory Neuroscience, University Medical Center, Göttingen, Germany
- Multiscale Bioimaging Cluster of Excellence (MBExC), University of Göttingen, Göttingen, Germany
| | - Marcelo Ganzella
- Laboratory of Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Peter J Johnson
- Department of Mathematical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Mathematics, University of Manchester, Manchester, UK
| | - Salome Veshaguri
- Center for Geometrically Engineered Cellular Membranes, Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
- Novozymes A/S, Kgs Lyngby, Denmark
| | - Jesper Holmkvist
- Center for Geometrically Engineered Cellular Membranes, Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
| | - Mads P Møller
- Center for Geometrically Engineered Cellular Membranes, Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
| | - Orestis Marantos
- Center for Geometrically Engineered Cellular Membranes, Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
| | - Frank Marcoline
- Cardiovascular Research Institute, Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, CA, USA
| | - Michael Grabe
- Cardiovascular Research Institute, Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, CA, USA
| | - Jesper L Pedersen
- Department of Mathematical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Reinhard Jahn
- Laboratory of Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Dimitrios Stamou
- Center for Geometrically Engineered Cellular Membranes, Department of Chemistry, University of Copenhagen, Copenhagen, Denmark.
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29
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Ditte Z, Silbern I, Ditte P, Urlaub H, Eichele G. Extracellular vesicles derived from the choroid plexus trigger the differentiation of neural stem cells. J Extracell Vesicles 2022; 11:e12276. [PMID: 36325603 PMCID: PMC9630752 DOI: 10.1002/jev2.12276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 09/26/2022] [Accepted: 10/14/2022] [Indexed: 11/06/2022] Open
Abstract
The choroid plexus secrets cerebrospinal fluid (CSF) composed of electrolytes, cytokines, growth factors, metabolites and extracellular vesicles (EVs) that flow through the interconnected brain ventricles. On their course, CSF components can act as signals that affect, for example, neural stem cells (NSCs) residing in niches of the ventricular wall. We studied EV-born CSF signals in an in vitro culture system. We purified EVs from the secretome of a choroid plexus cell line (Z310 cells), and from primary choroid plexus cultures and co-cultured those EVs with NSCs isolated from the niche of the lateral and the third ventricle. EVsZ310 and EVsCHP were purified by differential centrifugation. This yielded fractions of EVs of 50-150-nm diameter that induced a complex multicellular network formation and NSC differentiation. Both types of EV converted the round NSCs to cells that extended long processes that contacted nearby, alike-shaped cells. Mass spectrometry showed that the differentiation-inducing EVZ310 were enriched for membrane and membrane-associated proteins involved in cell differentiation, membrane trafficking, and membrane organization. We hypothesize that this type of EV Z310 cargo causes changes of stem cell morphology that leads to multicellular networks in the niches. This cell-shape transition may represent an initial step in NSC differentiation.
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Affiliation(s)
- Zuzana Ditte
- Department of Genes and BehaviorMax Planck Institute for Multidisciplinary SciencesGöttingenGermany
- Biological RhythmsMax Planck Institute for Dynamics and Self OrganizationGöttingenGermany
| | - Ivan Silbern
- The Bioanalytical Mass Spectrometry GroupMax Planck Institute for Multidisciplinary SciencesGöttingenGermany
- Institute for Clinical ChemistryUniversity Medical Center GöttingenGöttingenGermany
| | - Peter Ditte
- Department of Genes and BehaviorMax Planck Institute for Multidisciplinary SciencesGöttingenGermany
| | - Henning Urlaub
- The Bioanalytical Mass Spectrometry GroupMax Planck Institute for Multidisciplinary SciencesGöttingenGermany
- Institute for Clinical ChemistryUniversity Medical Center GöttingenGöttingenGermany
| | - Gregor Eichele
- Department of Genes and BehaviorMax Planck Institute for Multidisciplinary SciencesGöttingenGermany
- Biological RhythmsMax Planck Institute for Dynamics and Self OrganizationGöttingenGermany
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30
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Setting the Stage for Insulin Granule Dysfunction during Type-1-Diabetes: Is ER Stress the Culprit? Biomedicines 2022; 10:biomedicines10112695. [DOI: 10.3390/biomedicines10112695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 10/07/2022] [Accepted: 10/19/2022] [Indexed: 11/16/2022] Open
Abstract
Type-1-diabetes (T1D) is a multifactorial disorder with a global incidence of about 8.4 million individuals in 2021. It is primarily classified as an autoimmune disorder, where the pancreatic β-cells are unable to secrete sufficient insulin. This leads to elevated blood glucose levels (hyperglycemia). The development of T1D is an intricate interplay between various risk factors, such as genetic, environmental, and cellular elements. In this review, we focus on the cellular elements, such as ER (endoplasmic reticulum) stress and its consequences for T1D pathogenesis. One of the major repercussions of ER stress is defective protein processing. A well-studied example is that of islet amyloid polypeptide (IAPP), which is known to form cytotoxic amyloid plaques when misfolded. This review discusses the possible association between ER stress, IAPP, and amyloid formation in β-cells and its consequences in T1D. Additionally, ER stress also leads to autoantigen generation. This is driven by the loss of Ca++ ion homeostasis. Imbalanced Ca++ levels lead to abnormal activation of enzymes, causing post-translational modification of β-cell proteins. These modified proteins act as autoantigens and trigger the autoimmune response seen in T1D islets. Several of these autoantigens are also crucial for insulin granule biogenesis, processing, and release. Here, we explore the possible associations between ER stress leading to defects in insulin secretion and ultimately β-cell destruction.
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31
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Du K, Hu L, Wang P, Xue Y. Rapid isolation and cryo-EM characterization of synaptic vesicles from mammalian brain. FEBS Open Bio 2022; 12:1980-1987. [PMID: 36000326 PMCID: PMC9623512 DOI: 10.1002/2211-5463.13475] [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: 07/04/2022] [Revised: 07/26/2022] [Accepted: 08/22/2022] [Indexed: 01/25/2023] Open
Abstract
Synaptic vesicles (SVs) store and release neurotransmitters at chemical synapses. Precise regulation of SV trafficking, exocytosis and endocytosis is crucial for neural transmission. Biochemical characterization of SVs, which is essential for research into neurotransmitter uptake and release, requires effective in vitro isolation methods. Here, we describe an improved and simple purification protocol for isolating SVs from mouse brain within 6 h, achieving a yield of approximately 0.4 mg of SVs per single brain. The use of track-etch membrane filtration and iodixanol cushion ensured the uniform morphology of SVs and low contaminants in the sample. Cryo-electron microscopy was used to show that the in vitro isolated SVs retained intact membrane-associated proteins, and observation of SVs in hippocampal neurons using cryo-electron tomography confirmed the abundance of protein coating. Thus, our protocol allows effective isolation of SVs from small volumes of mammalian brain tissue, and the properties of the isolated SVs are close to those in vivo, making them suitable for biochemical analysis.
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Affiliation(s)
- Kang Du
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and TechnologyHuazhong University of Science and TechnologyWuhanChina,National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of BiophysicsChinese Academy of SciencesBeijingChina
| | - Liqiao Hu
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and TechnologyHuazhong University of Science and TechnologyWuhanChina
| | - Pei Wang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of BiophysicsChinese Academy of SciencesBeijingChina
| | - Yanhong Xue
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of BiophysicsChinese Academy of SciencesBeijingChina
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32
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Navarro-Paya C, Sanz-Hernandez M, De Simone A. Plasticity of Membrane Binding by the Central Region of α-Synuclein. Front Mol Biosci 2022; 9:857217. [PMID: 35782868 PMCID: PMC9240306 DOI: 10.3389/fmolb.2022.857217] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 05/02/2022] [Indexed: 12/20/2022] Open
Abstract
Membrane binding by α-synuclein (αS), an intrinsically disordered protein whose aggregation is associated with Parkinson’s disease, is a key step in determining its biological properties under both physiological and pathological conditions. Upon membrane interaction, αS retains a partial level of structural disorder despite acquiring α-helical content. In the membrane-bound state, the equilibrium between the helical-bound and disordered-detached states of the central region of αS (residues 65–97) has been involved in a double-anchor mechanism that promotes the clustering of synaptic vesicles. Herein, we investigated the underlying molecular bases of this equilibrium using enhanced coarse-grained molecular dynamics simulations. The results enabled clarifying the conformational dependencies of the membrane affinity by this protein region that, in addition to playing a role in physiological membrane binding, has key relevance for the aggregation of αS and the mechanisms of the toxicity of the resulting assemblies.
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Affiliation(s)
- Carlos Navarro-Paya
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | | | - Alfonso De Simone
- Department of Life Sciences, Imperial College London, London, United Kingdom
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
- *Correspondence: Alfonso De Simone,
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33
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Larocque G, Royle SJ. Integrating intracellular nanovesicles into integrin trafficking pathways and beyond. Cell Mol Life Sci 2022; 79:335. [PMID: 35657500 PMCID: PMC9166830 DOI: 10.1007/s00018-022-04371-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 04/28/2022] [Accepted: 05/11/2022] [Indexed: 12/24/2022]
Abstract
Membrane traffic controls the movement of proteins and lipids from one cellular compartment to another using a system of transport vesicles. Intracellular nanovesicles (INVs) are a newly described class of transport vesicles. These vesicles are small, carry diverse cargo, and are involved in multiple trafficking steps including anterograde traffic and endosomal recycling. An example of a biological process that they control is cell migration and invasion, due to their role in integrin recycling. In this review, we describe what is known so far about these vesicles. We discuss how INVs may integrate into established membrane trafficking pathways using integrin recycling as an example. We speculate where in the cell INVs have the potential to operate and we identify key questions for future investigation.
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Affiliation(s)
| | - Stephen J Royle
- Centre for Mechanochemical Cell Biology, Warwick Medical School, Gibbet Hill Road, Coventry, CV4 7AL, UK.
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34
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Carnazza KE, Komer LE, Xie YX, Pineda A, Briano JA, Gao V, Na Y, Ramlall T, Buchman VL, Eliezer D, Sharma M, Burré J. Synaptic vesicle binding of α-synuclein is modulated by β- and γ-synucleins. Cell Rep 2022; 39:110675. [PMID: 35417693 PMCID: PMC9116446 DOI: 10.1016/j.celrep.2022.110675] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Revised: 01/23/2022] [Accepted: 03/22/2022] [Indexed: 12/16/2022] Open
Abstract
α-synuclein, β-synuclein, and γ-synuclein are abundantly expressed proteins in the vertebrate nervous system. α-synuclein functions in neurotransmitter release by binding to and clustering synaptic vesicles and chaperoning SNARE-complex assembly. Pathologically, aggregates originating from soluble pools of α-synuclein are deposited into Lewy bodies in Parkinson's disease and related synucleinopathies. The functions of β-synuclein and γ-synuclein in presynaptic terminals remain poorly studied. Using in vitro liposome binding studies, circular dichroism spectroscopy, immunoprecipitation, and fluorescence resonance energy transfer (FRET) experiments on isolated synaptic vesicles in combination with subcellular fractionation of brains from synuclein mouse models, we show that β-synuclein and γ-synuclein have a reduced affinity toward synaptic vesicles compared with α-synuclein, and that heteromerization of β-synuclein or γ-synuclein with α-synuclein results in reduced synaptic vesicle binding of α-synuclein in a concentration-dependent manner. Our data suggest that β-synuclein and γ-synuclein are modulators of synaptic vesicle binding of α-synuclein and thereby reduce α-synuclein's physiological activity at the neuronal synapse.
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Affiliation(s)
- Kathryn E Carnazza
- Helen and Robert Appel Alzheimer's Disease Research Institute, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA
| | - Lauren E Komer
- Helen and Robert Appel Alzheimer's Disease Research Institute, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA
| | - Ying Xue Xie
- Helen and Robert Appel Alzheimer's Disease Research Institute, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA
| | - André Pineda
- Helen and Robert Appel Alzheimer's Disease Research Institute, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA
| | - Juan Antonio Briano
- Helen and Robert Appel Alzheimer's Disease Research Institute, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA
| | - Virginia Gao
- Helen and Robert Appel Alzheimer's Disease Research Institute, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA
| | - Yoonmi Na
- Helen and Robert Appel Alzheimer's Disease Research Institute, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA
| | - Trudy Ramlall
- Department of Biochemistry, Weill Cornell Medicine, New York, NY 10021, USA
| | - Vladimir L Buchman
- School of Biosciences, Cardiff University, Cardiff CF103AX, UK; Belgorod State National Research University, 85 Pobedy Street, Belgorod, Belgorod 308015, Russian Federation
| | - David Eliezer
- Department of Biochemistry, Weill Cornell Medicine, New York, NY 10021, USA
| | - Manu Sharma
- Helen and Robert Appel Alzheimer's Disease Research Institute, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA
| | - Jacqueline Burré
- Helen and Robert Appel Alzheimer's Disease Research Institute, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA.
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35
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Kohler I, Verhoeven M, Haselberg R, Gargano AF. Hydrophilic interaction chromatography – mass spectrometry for metabolomics and proteomics: state-of-the-art and current trends. Microchem J 2022. [DOI: 10.1016/j.microc.2021.106986] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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36
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Gundelfinger ED, Karpova A, Pielot R, Garner CC, Kreutz MR. Organization of Presynaptic Autophagy-Related Processes. Front Synaptic Neurosci 2022; 14:829354. [PMID: 35368245 PMCID: PMC8968026 DOI: 10.3389/fnsyn.2022.829354] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Accepted: 01/04/2022] [Indexed: 11/13/2022] Open
Abstract
Brain synapses pose special challenges on the quality control of their protein machineries as they are far away from the neuronal soma, display a high potential for plastic adaptation and have a high energy demand to fulfill their physiological tasks. This applies in particular to the presynaptic part where neurotransmitter is released from synaptic vesicles, which in turn have to be recycled and refilled in a complex membrane trafficking cycle. Pathways to remove outdated and damaged proteins include the ubiquitin-proteasome system acting in the cytoplasm as well as membrane-associated endolysosomal and the autophagy systems. Here we focus on the latter systems and review what is known about the spatial organization of autophagy and endolysomal processes within the presynapse. We provide an inventory of which components of these degradative systems were found to be present in presynaptic boutons and where they might be anchored to the presynaptic apparatus. We identify three presynaptic structures reported to interact with known constituents of membrane-based protein-degradation pathways and therefore may serve as docking stations. These are (i) scaffolding proteins of the cytomatrix at the active zone, such as Bassoon or Clarinet, (ii) the endocytic machinery localized mainly at the peri-active zone, and (iii) synaptic vesicles. Finally, we sketch scenarios, how presynaptic autophagic cargos are tagged and recruited and which cellular mechanisms may govern membrane-associated protein turnover in the presynapse.
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Affiliation(s)
- Eckart D. Gundelfinger
- Research Group Neuroplasticity, Leibniz Institute for Neurobiology, Magdeburg, Germany
- Institute of Pharmacology and Toxicology, Medical Faculty, Otto von Guericke University, Magdeburg, Germany
- Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany
- *Correspondence: Eckart D. Gundelfinger,
| | - Anna Karpova
- Research Group Neuroplasticity, Leibniz Institute for Neurobiology, Magdeburg, Germany
- Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany
| | - Rainer Pielot
- Institute of Pharmacology and Toxicology, Medical Faculty, Otto von Guericke University, Magdeburg, Germany
- Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany
| | - Craig C. Garner
- German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany
- Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Michael R. Kreutz
- Research Group Neuroplasticity, Leibniz Institute for Neurobiology, Magdeburg, Germany
- Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany
- Center for Molecular Neurobiology (ZMNH), University Hospital Hamburg-Eppendorf, Hamburg, Germany
- German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
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37
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Upmanyu N, Jin J, Emde HVD, Ganzella M, Bösche L, Malviya VN, Zhuleku E, Politi AZ, Ninov M, Silbern I, Leutenegger M, Urlaub H, Riedel D, Preobraschenski J, Milosevic I, Hell SW, Jahn R, Sambandan S. Colocalization of different neurotransmitter transporters on synaptic vesicles is sparse except for VGLUT1 and ZnT3. Neuron 2022; 110:1483-1497.e7. [PMID: 35263617 DOI: 10.1016/j.neuron.2022.02.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 01/08/2022] [Accepted: 02/10/2022] [Indexed: 12/26/2022]
Abstract
Vesicular transporters (VTs) define the type of neurotransmitter that synaptic vesicles (SVs) store and release. While certain mammalian neurons release multiple transmitters, it is not clear whether the release occurs from the same or distinct vesicle pools at the synapse. Using quantitative single-vesicle imaging, we show that a vast majority of SVs in the rodent brain contain only one type of VT, indicating specificity for a single neurotransmitter. Interestingly, SVs containing dual transporters are highly diverse (27 types) but small in proportion (2% of all SVs), excluding the largest pool that carries VGLUT1 and ZnT3 (34%). Using VGLUT1-ZnT3 SVs, we demonstrate that the transporter colocalization influences the SV content and synaptic quantal size. Thus, the presence of diverse transporters on the same vesicle is bona fide, and depending on the VT types, this may act to regulate neurotransmitter type, content, and release in space and time.
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Affiliation(s)
- Neha Upmanyu
- Synaptic Metal Ion Dynamics and Signaling, Max Planck Institute for Multidisciplinary Sciences, Göttingen 37077, Germany; Laboratory of Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen 37077, Germany
| | - Jialin Jin
- European Neurosciences Institute, A Joint Initiative of the University Medical Center Göttingen and the Max Planck Society, Göttingen 37077, Germany
| | - Henrik von der Emde
- Department of NanoBiophotonics, Max Planck Institute for Multidisciplinary Sciences, Göttingen 37077, Germany
| | - Marcelo Ganzella
- Laboratory of Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen 37077, Germany
| | - Leon Bösche
- Synaptic Metal Ion Dynamics and Signaling, Max Planck Institute for Multidisciplinary Sciences, Göttingen 37077, Germany; Laboratory of Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen 37077, Germany
| | - Viveka Nand Malviya
- Laboratory of Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen 37077, Germany
| | - Evi Zhuleku
- Laboratory of Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen 37077, Germany
| | - Antonio Zaccaria Politi
- Live-Cell Imaging Facility, Max Planck Institute for Multidisciplinary Sciences, Göttingen 37077, Germany
| | - Momchil Ninov
- Bioanalytical Mass Spectrometry, Max Planck Institute for Multidisciplinary Sciences, Göttingen 37077, Germany; Institute of Clinical Chemistry, University Medical Center Göttingen, Göttingen 37075, Germany
| | - Ivan Silbern
- Bioanalytical Mass Spectrometry, Max Planck Institute for Multidisciplinary Sciences, Göttingen 37077, Germany; Institute of Clinical Chemistry, University Medical Center Göttingen, Göttingen 37075, Germany
| | - Marcel Leutenegger
- Department of NanoBiophotonics, Max Planck Institute for Multidisciplinary Sciences, Göttingen 37077, Germany
| | - Henning Urlaub
- Bioanalytical Mass Spectrometry, Max Planck Institute for Multidisciplinary Sciences, Göttingen 37077, Germany; Institute of Clinical Chemistry, University Medical Center Göttingen, Göttingen 37075, Germany
| | - Dietmar Riedel
- Department of Structural Dynamics, Max Planck Institute for Multidisciplinary Sciences, Göttingen 37077, Germany
| | - Julia Preobraschenski
- Laboratory of Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen 37077, Germany; Institute for Auditory Neuroscience, University Medical Center Göttingen, Göttingen 37075, Germany; Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), University of Göttingen, Göttingen 37075, Germany
| | - Ira Milosevic
- Wellcome Centre for Human Genetics, Nuffield Department of Medicine, NIHR Oxford Biomedical Research Centre, University of Oxford, Oxford OX3 7BN, UK; Multidisciplinary Institute of Ageing, MIA-Portugal, University of Coimbra, Coimbra 3000-370, Portugal
| | - Stefan W Hell
- Department of NanoBiophotonics, Max Planck Institute for Multidisciplinary Sciences, Göttingen 37077, Germany; Department of Optical Nanoscopy, Max Planck Institute for Medical Research, Heidelberg 69028, Germany
| | - Reinhard Jahn
- Laboratory of Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen 37077, Germany
| | - Sivakumar Sambandan
- Synaptic Metal Ion Dynamics and Signaling, Max Planck Institute for Multidisciplinary Sciences, Göttingen 37077, Germany; Laboratory of Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen 37077, Germany; Department of NanoBiophotonics, Max Planck Institute for Multidisciplinary Sciences, Göttingen 37077, Germany.
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38
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Yang S, Park D, Manning L, Hill SE, Cao M, Xuan Z, Gonzalez I, Dong Y, Clark B, Shao L, Okeke I, Almoril-Porras A, Bai J, De Camilli P, Colón-Ramos DA. Presynaptic autophagy is coupled to the synaptic vesicle cycle via ATG-9. Neuron 2022; 110:824-840.e10. [PMID: 35065714 PMCID: PMC9017068 DOI: 10.1016/j.neuron.2021.12.031] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 10/20/2021] [Accepted: 12/20/2021] [Indexed: 01/01/2023]
Abstract
Autophagy is a cellular degradation pathway essential for neuronal health and function. Autophagosome biogenesis occurs at synapses, is locally regulated, and increases in response to neuronal activity. The mechanisms that couple autophagosome biogenesis to synaptic activity remain unknown. In this study, we determine that trafficking of ATG-9, the only transmembrane protein in the core autophagy pathway, links the synaptic vesicle cycle with autophagy. ATG-9-positive vesicles in C. elegans are generated from the trans-Golgi network via AP-3-dependent budding and delivered to presynaptic sites. At presynaptic sites, ATG-9 undergoes exo-endocytosis in an activity-dependent manner. Mutations that disrupt endocytosis, including a lesion in synaptojanin 1 associated with Parkinson's disease, result in abnormal ATG-9 accumulation at clathrin-rich synaptic foci and defects in activity-induced presynaptic autophagy. Our findings uncover regulated key steps of ATG-9 trafficking at presynaptic sites and provide evidence that ATG-9 exo-endocytosis couples autophagosome biogenesis at presynaptic sites with the activity-dependent synaptic vesicle cycle.
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Affiliation(s)
- Sisi Yang
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Neuroscience and of Cell Biology, Yale University School of Medicine, 260 Whitney Avenue, YSB C167, New Haven, CT 06511, USA
| | - Daehun Park
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Neuroscience and of Cell Biology, Yale University School of Medicine, 260 Whitney Avenue, YSB C167, New Haven, CT 06511, USA; Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, CT 06510, USA; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Laura Manning
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Neuroscience and of Cell Biology, Yale University School of Medicine, 260 Whitney Avenue, YSB C167, New Haven, CT 06511, USA
| | - Sarah E Hill
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Neuroscience and of Cell Biology, Yale University School of Medicine, 260 Whitney Avenue, YSB C167, New Haven, CT 06511, USA
| | - Mian Cao
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Neuroscience and of Cell Biology, Yale University School of Medicine, 260 Whitney Avenue, YSB C167, New Haven, CT 06511, USA; Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, CT 06510, USA; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Zhao Xuan
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Neuroscience and of Cell Biology, Yale University School of Medicine, 260 Whitney Avenue, YSB C167, New Haven, CT 06511, USA
| | - Ian Gonzalez
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Neuroscience and of Cell Biology, Yale University School of Medicine, 260 Whitney Avenue, YSB C167, New Haven, CT 06511, USA
| | - Yongming Dong
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Benjamin Clark
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Neuroscience and of Cell Biology, Yale University School of Medicine, 260 Whitney Avenue, YSB C167, New Haven, CT 06511, USA
| | - Lin Shao
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Neuroscience and of Cell Biology, Yale University School of Medicine, 260 Whitney Avenue, YSB C167, New Haven, CT 06511, USA
| | - Ifechukwu Okeke
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Neuroscience and of Cell Biology, Yale University School of Medicine, 260 Whitney Avenue, YSB C167, New Haven, CT 06511, USA
| | - Agustin Almoril-Porras
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Neuroscience and of Cell Biology, Yale University School of Medicine, 260 Whitney Avenue, YSB C167, New Haven, CT 06511, USA
| | - Jihong Bai
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Pietro De Camilli
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Neuroscience and of Cell Biology, Yale University School of Medicine, 260 Whitney Avenue, YSB C167, New Haven, CT 06511, USA; Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, CT 06510, USA; Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT 06510, USA; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Daniel A Colón-Ramos
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Neuroscience and of Cell Biology, Yale University School of Medicine, 260 Whitney Avenue, YSB C167, New Haven, CT 06511, USA; Instituto de Neurobiología José del Castillo, Recinto de Ciencias Médicas, Universidad de Puerto Rico, 201 Boulevard del Valle, San Juan, PR 00901, USA; Wu Tsai Institute, Yale University, New Haven, CT 06510, USA.
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39
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Ivanova D, Cousin MA. Synaptic Vesicle Recycling and the Endolysosomal System: A Reappraisal of Form and Function. Front Synaptic Neurosci 2022; 14:826098. [PMID: 35280702 PMCID: PMC8916035 DOI: 10.3389/fnsyn.2022.826098] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 02/03/2022] [Indexed: 12/15/2022] Open
Abstract
The endolysosomal system is present in all cell types. Within these cells, it performs a series of essential roles, such as trafficking and sorting of membrane cargo, intracellular signaling, control of metabolism and degradation. A specific compartment within central neurons, called the presynapse, mediates inter-neuronal communication via the fusion of neurotransmitter-containing synaptic vesicles (SVs). The localized recycling of SVs and their organization into functional pools is widely assumed to be a discrete mechanism, that only intersects with the endolysosomal system at specific points. However, evidence is emerging that molecules essential for endolysosomal function also have key roles within the SV life cycle, suggesting that they form a continuum rather than being isolated processes. In this review, we summarize the evidence for key endolysosomal molecules in SV recycling and propose an alternative model for membrane trafficking at the presynapse. This includes the hypotheses that endolysosomal intermediates represent specific functional SV pools, that sorting of cargo to SVs is mediated via the endolysosomal system and that manipulation of this process can result in both plastic changes to neurotransmitter release and pathophysiology via neurodegeneration.
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Affiliation(s)
- Daniela Ivanova
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Muir Maxwell Epilepsy Centre, University of Edinburgh, Edinburgh, United Kingdom
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, United Kingdom
- *Correspondence: Daniela Ivanova,
| | - Michael A. Cousin
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Muir Maxwell Epilepsy Centre, University of Edinburgh, Edinburgh, United Kingdom
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, United Kingdom
- Michael A. Cousin,
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40
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Azarnia Tehran D, Maritzen T. Endocytic proteins: An expanding repertoire of presynaptic functions. Curr Opin Neurobiol 2022; 73:102519. [PMID: 35217312 DOI: 10.1016/j.conb.2022.01.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 01/14/2022] [Accepted: 01/19/2022] [Indexed: 12/16/2022]
Abstract
From a presynaptic perspective, neuronal communication mainly relies on two interdependent events: The fast Ca2+-triggered fusion of neurotransmitter-containing synaptic vesicles (SVs) and their subsequent high-fidelity reformation. To allow rapid neurotransmission, SVs have evolved into fascinating molecular nanomachines equipped with a well-defined set of proteins. However, upon exocytosis, SVs fully collapse into the presynaptic plasma membrane leading to the dispersal of their molecular components. While the canonical function of endocytic proteins at the presynapse was believed to be the retrieval of SV proteins via clathrin-mediated endocytosis, it is now evident that clathrin-independent endocytic mechanisms predominate. We will highlight in how far these mechanisms still rely on the classical endocytic machinery and discuss the emerging functions of endocytic proteins in release site clearance and SV reformation from endosomal-like vacuoles.
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Affiliation(s)
- Domenico Azarnia Tehran
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Robert-Roessle-Straße 10, 13125, Berlin, Germany. https://twitter.com/@DomenicoAzTe
| | - Tanja Maritzen
- Department of Nanophysiology, Technische Universität Kaiserslautern, Paul-Ehrlich-Straße 23, 67663, Kaiserslautern, Germany.
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41
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Xia X, Wang Y, Qin Y, Zhao S, Zheng JC. Exosome: A novel neurotransmission modulator or non-canonical neurotransmitter? Ageing Res Rev 2022; 74:101558. [PMID: 34990846 DOI: 10.1016/j.arr.2021.101558] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 08/13/2021] [Accepted: 12/30/2021] [Indexed: 02/08/2023]
Abstract
Neurotransmission is the electrical impulse-triggered propagation of signals between neurons or between neurons and other cell types such as skeletal muscle cells. Recent studies point out the involvement of exosomes, a type of small bilipid layer-enclosed extracellular vesicles, in regulating neurotransmission. Through horizontally transferring proteins, lipids, and nucleic acids, exosomes can modulate synaptic activities rapidly by controlling neurotransmitter release or progressively by regulating neural plasticity including synapse formation, neurite growth & removal, and axon guidance & elongation. In this review, we summarize the similarities and differences between exosomes and synaptic vesicles in their biogenesis, contents, and release. We also highlight the recent progress made in demonstrating the biological roles of exosome in regulating neurotransmission, and propose a modified model of neurotransmission, in which exosomes act as novel neurotransmitters. Lastly, we provide a comprehensive discussion of the enlightenment of the current knowledge on neurotransmission to the future directions of exosome research.
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42
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Hori T, Takamori S. Physiological Perspectives on Molecular Mechanisms and Regulation of Vesicular Glutamate Transport: Lessons From Calyx of Held Synapses. Front Cell Neurosci 2022; 15:811892. [PMID: 35095427 PMCID: PMC8793065 DOI: 10.3389/fncel.2021.811892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 12/07/2021] [Indexed: 12/02/2022] Open
Abstract
Accumulation of glutamate, the primary excitatory neurotransmitter in the mammalian central nervous system, into presynaptic synaptic vesicles (SVs) depends upon three vesicular glutamate transporters (VGLUTs). Since VGLUTs are driven by a proton electrochemical gradient across the SV membrane generated by vacuolar-type H+-ATPases (V-ATPases), the rate of glutamate transport into SVs, as well as the amount of glutamate in SVs at equilibrium, are influenced by activities of both VGLUTs and V-ATPase. Despite emerging evidence that suggests various factors influencing glutamate transport by VGLUTs in vitro, little has been reported in physiological or pathological contexts to date. Historically, this was partially due to a lack of appropriate methods to monitor glutamate loading into SVs in living synapses. Furthermore, whether or not glutamate refilling of SVs can be rate-limiting for synaptic transmission is not well understood, primarily due to a lack of knowledge concerning the time required for vesicle reuse and refilling during repetitive stimulation. In this review, we first introduce a unique electrophysiological method to monitor glutamate refilling by VGLUTs in a giant model synapse from the calyx of Held in rodent brainstem slices, and we discuss the advantages and limitations of the method. We then introduce the current understanding of factors that potentially alter the amount and rate of glutamate refilling of SVs in this synapse, and discuss open questions from physiological viewpoints.
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Affiliation(s)
- Tetsuya Hori
- Cellular and Molecular Synaptic Function Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
- *Correspondence: Tetsuya Hori Shigeo Takamori
| | - Shigeo Takamori
- Laboratory of Neural Membrane Biology, Graduate School of Brain Science, Doshisha University, Kyoto, Japan
- *Correspondence: Tetsuya Hori Shigeo Takamori
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López-Hernández T, Takenaka KI, Mori Y, Kongpracha P, Nagamori S, Haucke V, Takamori S. Clathrin-independent endocytic retrieval of SV proteins mediated by the clathrin adaptor AP-2 at mammalian central synapses. eLife 2022; 11:e71198. [PMID: 35014951 PMCID: PMC8752090 DOI: 10.7554/elife.71198] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 12/28/2021] [Indexed: 12/25/2022] Open
Abstract
Neurotransmission is based on the exocytic fusion of synaptic vesicles (SVs) followed by endocytic membrane retrieval and the reformation of SVs. Conflicting models have been proposed regarding the mechanisms of SV endocytosis, most notably clathrin/adaptor protein complex 2 (AP-2)-mediated endocytosis and clathrin-independent ultrafast endocytosis. Partitioning between these pathways has been suggested to be controlled by temperature and stimulus paradigm. We report on the comprehensive survey of six major SV proteins to show that SV endocytosis in mouse hippocampal neurons at physiological temperature occurs independent of clathrin while the endocytic retrieval of a subset of SV proteins including the vesicular transporters for glutamate and GABA depend on sorting by the clathrin adaptor AP-2. Our findings highlight a clathrin-independent role of the clathrin adaptor AP-2 in the endocytic retrieval of select SV cargos from the presynaptic cell surface and suggest a revised model for the endocytosis of SV membranes at mammalian central synapses.
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Affiliation(s)
| | - Koh-ichiro Takenaka
- Laboratory of Neural Membrane Biology, Graduate School of Brain Science, Doshisha UniversityKyotoJapan
| | - Yasunori Mori
- Laboratory of Neural Membrane Biology, Graduate School of Brain Science, Doshisha UniversityKyotoJapan
| | - Pornparn Kongpracha
- Department of Laboratory Medicine, The Jikei University School of MedicineTokyoJapan
| | - Shushi Nagamori
- Department of Laboratory Medicine, The Jikei University School of MedicineTokyoJapan
| | - Volker Haucke
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP)BerlinGermany
| | - Shigeo Takamori
- Laboratory of Neural Membrane Biology, Graduate School of Brain Science, Doshisha UniversityKyotoJapan
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Kongpracha P, Wiriyasermkul P, Isozumi N, Moriyama S, Kanai Y, Nagamori S. Simple but efficacious enrichment of integral membrane proteins and their interactions for in-depth membrane proteomics. Mol Cell Proteomics 2022; 21:100206. [PMID: 35085786 PMCID: PMC9062332 DOI: 10.1016/j.mcpro.2022.100206] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 12/13/2021] [Accepted: 01/20/2022] [Indexed: 12/19/2022] Open
Abstract
Membrane proteins play essential roles in various cellular processes, such as nutrient transport, bioenergetic processes, cell adhesion, and signal transduction. Proteomics is one of the key approaches to exploring membrane proteins comprehensively. Bottom–up proteomics using LC–MS/MS has been widely used in membrane proteomics. However, the low abundance and hydrophobic features of membrane proteins, especially integral membrane proteins, make it difficult to handle the proteins and are the bottleneck for identification by LC–MS/MS. Herein, to improve the identification and quantification of membrane proteins, we have stepwisely evaluated methods of membrane enrichment for the sample preparation. The enrichment methods of membranes consisted of precipitation by ultracentrifugation and treatment by urea or alkaline solutions. The best enrichment method in the study, washing with urea after isolation of the membranes, resulted in the identification of almost twice as many membrane proteins compared with samples without the enrichment. Notably, the method significantly enhances the identified numbers of multispanning transmembrane proteins, such as solute carrier transporters, ABC transporters, and G-protein–coupled receptors, by almost sixfold. Using this method, we revealed the profiles of amino acid transport systems with the validation by functional assays and found more protein–protein interactions, including membrane protein complexes and clusters. Our protocol uses standard procedures in biochemistry, but the method was efficient for the in-depth analysis of membrane proteome in a wide range of samples. Fractionation of membranes improves the identification of membrane proteins. Membranes washed with urea or alkaline increase identified transmembrane proteins. Urea wash increases the detection of multispanning transmembrane proteins. Proteomics of urea-washed membranes keeps more protein–protein interactions.
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Affiliation(s)
- Pornparn Kongpracha
- Department of Laboratory Medicine, The Jikei University School of Medicine, Tokyo, Japan; Department of Collaborative Research for Biomolecular Dynamics, Nara Medical University, Nara, Japan
| | - Pattama Wiriyasermkul
- Department of Laboratory Medicine, The Jikei University School of Medicine, Tokyo, Japan; Department of Collaborative Research for Biomolecular Dynamics, Nara Medical University, Nara, Japan
| | - Noriyoshi Isozumi
- Department of Bio-system Pharmacology, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Satomi Moriyama
- Department of Collaborative Research for Biomolecular Dynamics, Nara Medical University, Nara, Japan
| | - Yoshikatsu Kanai
- Department of Bio-system Pharmacology, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Shushi Nagamori
- Department of Laboratory Medicine, The Jikei University School of Medicine, Tokyo, Japan; Department of Collaborative Research for Biomolecular Dynamics, Nara Medical University, Nara, Japan.
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Decet M, Verstreken P. Presynaptic Autophagy and the Connection With Neurotransmission. Front Cell Dev Biol 2021; 9:790721. [PMID: 34988081 PMCID: PMC8722708 DOI: 10.3389/fcell.2021.790721] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 12/01/2021] [Indexed: 01/14/2023] Open
Abstract
Autophagy is an evolutionary conserved catabolic pathway essential for the maintenance of cellular homeostasis. Defective proteins and organelles are engulfed by autophagosomal membranes which fuse with lysosomes for cargo degradation. In neurons, the orchestrated progression of autophagosome formation and maturation occurs in distinct subcellular compartments. For synapses, the distance from the soma and the oxidative stress generated during intense neuronal activity pose a challenge to maintain protein homeostasis. Autophagy constitutes a crucial mechanism for proper functioning of this unique and vulnerable cellular compartment. We are now beginning to understand how autophagy is regulated at pre-synaptic terminals and how this pathway, when imbalanced, impacts on synaptic function and -ultimately- neuronal survival. We review here the current state of the art of "synaptic autophagy", with an emphasis on the biogenesis of autophagosomes at the pre-synaptic compartment. We provide an overview of the existing knowledge on the signals inducing autophagy at synapses, highlight the interplay between autophagy and neurotransmission, and provide perspectives for future research.
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Affiliation(s)
- Marianna Decet
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Mission Lucidity, Leuven, Belgium
| | - Patrik Verstreken
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Mission Lucidity, Leuven, Belgium
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Qian C, Wu Z, Sun R, Yu H, Zeng J, Rao Y, Li Y. Localization, proteomics, and metabolite profiling reveal a putative vesicular transporter for UDP-glucose. eLife 2021; 10:65417. [PMID: 34269178 PMCID: PMC8373376 DOI: 10.7554/elife.65417] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 07/15/2021] [Indexed: 11/27/2022] Open
Abstract
Vesicular neurotransmitter transporters (VNTs) mediate the selective uptake and enrichment of small-molecule neurotransmitters into synaptic vesicles (SVs) and are therefore a major determinant of the synaptic output of specific neurons. To identify novel VNTs expressed on SVs (thus identifying new neurotransmitters and/or neuromodulators), we conducted localization profiling of 361 solute carrier (SLC) transporters tagging with a fluorescent protein in neurons, which revealed 40 possible candidates through comparison with a known SV marker. We parallelly performed proteomics analysis of immunoisolated SVs and identified seven transporters in overlap. Ultrastructural analysis further supported that one of the transporters, SLC35D3, localized to SVs. Finally, by combining metabolite profiling with a radiolabeled substrate transport assay, we identified UDP-glucose as the principal substrate for SLC35D3. These results provide new insights into the functional role of SLC transporters in neurotransmission and improve our understanding of the molecular diversity of chemical transmitters.
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Affiliation(s)
- Cheng Qian
- School of Life Sciences, Tsinghua University, Beijing, China
| | - Zhaofa Wu
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China.,PKU-IDG/McGovern Institute for Brain Research, Beijing, China
| | - Rongbo Sun
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China.,PKU-IDG/McGovern Institute for Brain Research, Beijing, China
| | - Huasheng Yu
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China.,PKU-IDG/McGovern Institute for Brain Research, Beijing, China.,Peking-Tsinghua Center for Life Sciences, Beijing, China
| | - Jianzhi Zeng
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China.,PKU-IDG/McGovern Institute for Brain Research, Beijing, China.,Peking-Tsinghua Center for Life Sciences, Beijing, China
| | - Yi Rao
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China.,PKU-IDG/McGovern Institute for Brain Research, Beijing, China.,Peking-Tsinghua Center for Life Sciences, Beijing, China.,Chinese Institute for Brain Research, Beijing, China
| | - Yulong Li
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China.,PKU-IDG/McGovern Institute for Brain Research, Beijing, China.,Peking-Tsinghua Center for Life Sciences, Beijing, China.,Chinese Institute for Brain Research, Beijing, China
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Di Paolo A, Garat J, Eastman G, Farias J, Dajas-Bailador F, Smircich P, Sotelo-Silveira JR. Functional Genomics of Axons and Synapses to Understand Neurodegenerative Diseases. Front Cell Neurosci 2021; 15:686722. [PMID: 34248504 PMCID: PMC8267896 DOI: 10.3389/fncel.2021.686722] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Accepted: 06/02/2021] [Indexed: 01/02/2023] Open
Abstract
Functional genomics studies through transcriptomics, translatomics and proteomics have become increasingly important tools to understand the molecular basis of biological systems in the last decade. In most cases, when these approaches are applied to the nervous system, they are centered in cell bodies or somatodendritic compartments, as these are easier to isolate and, at least in vitro, contain most of the mRNA and proteins present in all neuronal compartments. However, key functional processes and many neuronal disorders are initiated by changes occurring far away from cell bodies, particularly in axons (axopathologies) and synapses (synaptopathies). Both neuronal compartments contain specific RNAs and proteins, which are known to vary depending on their anatomical distribution, developmental stage and function, and thus form the complex network of molecular pathways required for neuron connectivity. Modifications in these components due to metabolic, environmental, and/or genetic issues could trigger or exacerbate a neuronal disease. For this reason, detailed profiling and functional understanding of the precise changes in these compartments may thus yield new insights into the still intractable molecular basis of most neuronal disorders. In the case of synaptic dysfunctions or synaptopathies, they contribute to dozens of diseases in the human brain including neurodevelopmental (i.e., autism, Down syndrome, and epilepsy) as well as neurodegenerative disorders (i.e., Alzheimer's and Parkinson's diseases). Histological, biochemical, cellular, and general molecular biology techniques have been key in understanding these pathologies. Now, the growing number of omics approaches can add significant extra information at a high and wide resolution level and, used effectively, can lead to novel and insightful interpretations of the biological processes at play. This review describes current approaches that use transcriptomics, translatomics and proteomic related methods to analyze the axon and presynaptic elements, focusing on the relationship that axon and synapses have with neurodegenerative diseases.
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Affiliation(s)
- Andres Di Paolo
- Departamento de Genómica, Instituto de Investigaciones Biológicas Clemente Estable (IIBCE), Montevideo, Uruguay
- Departamento de Proteínas y Ácidos Nucleicos, Instituto de Investigaciones Biológicas Clemente Estable (IIBCE), Montevideo, Uruguay
| | - Joaquin Garat
- Departamento de Genómica, Instituto de Investigaciones Biológicas Clemente Estable (IIBCE), Montevideo, Uruguay
| | - Guillermo Eastman
- Departamento de Genómica, Instituto de Investigaciones Biológicas Clemente Estable (IIBCE), Montevideo, Uruguay
| | - Joaquina Farias
- Departamento de Genómica, Instituto de Investigaciones Biológicas Clemente Estable (IIBCE), Montevideo, Uruguay
- Polo de Desarrollo Universitario “Espacio de Biología Vegetal del Noreste”, Centro Universitario Regional Noreste, Universidad de la República (UdelaR), Tacuarembó, Uruguay
| | - Federico Dajas-Bailador
- School of Life Sciences, Medical School Building, University of Nottingham, Nottingham, United Kingdom
| | - Pablo Smircich
- Departamento de Genómica, Instituto de Investigaciones Biológicas Clemente Estable (IIBCE), Montevideo, Uruguay
- Laboratorio de Interacciones Moleculares, Facultad de Ciencias, Universidad de la República (UdelaR), Montevideo, Uruguay
| | - José Roberto Sotelo-Silveira
- Departamento de Genómica, Instituto de Investigaciones Biológicas Clemente Estable (IIBCE), Montevideo, Uruguay
- Departamento de Biología Celular y Molecular, Facultad de Ciencias, Universidad de la República (UdelaR), Montevideo, Uruguay
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Binotti B, Jahn R, Pérez-Lara Á. An overview of the synaptic vesicle lipid composition. Arch Biochem Biophys 2021; 709:108966. [PMID: 34139199 DOI: 10.1016/j.abb.2021.108966] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 06/10/2021] [Accepted: 06/10/2021] [Indexed: 11/29/2022]
Abstract
Chemical neurotransmission is the major mechanism of neuronal communication. Neurotransmitters are released from secretory organelles, the synaptic vesicles (SVs) via exocytosis into the synaptic cleft. Fusion of SVs with the presynaptic plasma membrane is balanced by endocytosis, thus maintaining the presynaptic membrane at steady-state levels. The protein machineries responsible for exo- and endocytosis have been extensively investigated. In contrast, less is known about the role of lipids in synaptic transmission and how the lipid composition of SVs is affected by dynamic exo-endocytotic cycling. Here we summarize the current knowledge about the composition, organization, and function of SV membrane lipids. We also cover lipid biogenesis and maintenance during the synaptic vesicle cycle.
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Affiliation(s)
- Beyenech Binotti
- Department of Biochemistry, University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Reinhard Jahn
- Department of Neurobiology, Max-Planck-Institute for Biophysical Chemistry, Am Faßberg 11, 37077, Göttingen, Germany.
| | - Ángel Pérez-Lara
- Department of Physical Chemistry, University of Granada, Campus Universitario de Cartuja, 18071, Granada, Spain.
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A unified resource and configurable model of the synapse proteome and its role in disease. Sci Rep 2021; 11:9967. [PMID: 33976238 PMCID: PMC8113277 DOI: 10.1038/s41598-021-88945-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 04/15/2021] [Indexed: 02/03/2023] Open
Abstract
Genes encoding synaptic proteins are highly associated with neuronal disorders many of which show clinical co-morbidity. We integrated 58 published synaptic proteomic datasets that describe over 8000 proteins and combined them with direct protein-protein interactions and functional metadata to build a network resource that reveals the shared and unique protein components that underpin multiple disorders. All the data are provided in a flexible and accessible format to encourage custom use.
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León A, Aparicio GI, Scorticati C. Neuronal Glycoprotein M6a: An Emerging Molecule in Chemical Synapse Formation and Dysfunction. Front Synaptic Neurosci 2021; 13:661681. [PMID: 34017241 PMCID: PMC8129562 DOI: 10.3389/fnsyn.2021.661681] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Accepted: 04/07/2021] [Indexed: 12/27/2022] Open
Abstract
The cellular and molecular mechanisms underlying neuropsychiatric and neurodevelopmental disorders show that most of them can be categorized as synaptopathies-or damage of synaptic function and plasticity. Synaptic formation and maintenance are orchestrated by protein complexes that are in turn regulated in space and time during neuronal development allowing synaptic plasticity. However, the exact mechanisms by which these processes are managed remain unknown. Large-scale genomic and proteomic projects led to the discovery of new molecules and their associated variants as disease risk factors. Neuronal glycoprotein M6a, encoded by the GPM6A gene is emerging as one of these molecules. M6a has been involved in neuron development and synapse formation and plasticity, and was also recently proposed as a gene-target in various neuropsychiatric disorders where it could also be used as a biomarker. In this review, we provide an overview of the structure and molecular mechanisms by which glycoprotein M6a participates in synapse formation and maintenance. We also review evidence collected from patients carrying mutations in the GPM6A gene; animal models, and in vitro studies that together emphasize the relevance of M6a, particularly in synapses and in neurological conditions.
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Affiliation(s)
| | | | - Camila Scorticati
- Instituto de Investigaciones Biotecnológicas “Rodolfo A. Ugalde”, Universidad Nacional de San Martín and Consejo Nacional de Investigaciones Científicas y Técnicas (IIBio-UNSAM-CONICET), Buenos Aires, Argentina
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