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Schwab K, Lauer D, Magbagbeolu M, Theuring F, Gasiorowska A, Zadrozny M, Harrington CR, Wischik CM, Niewiadomska G, Riedel G. Hydromethylthionine rescues synaptic SNARE proteins in a mouse model of tauopathies: Interference by cholinesterase inhibitors. Brain Res Bull 2024; 212:110955. [PMID: 38677558 DOI: 10.1016/j.brainresbull.2024.110955] [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: 02/29/2024] [Revised: 04/14/2024] [Accepted: 04/17/2024] [Indexed: 04/29/2024]
Abstract
In clinical trials for Alzheimer's disease (AD), hydromethylthionine mesylate (HMTM) showed reduced efficacy when administered as an add-on to symptomatic treatments, while it produced a significant improvement of cognitive function when taken as monotherapy. Interference of cholinesterase inhibition with HMTM was observed also in a tau transgenic mouse model, where rivastigmine reduced the pharmacological activity of HMTM at multiple brain levels including hippocampal acetylcholine release, synaptosomal glutamate release and mitochondrial activity. Here, we examined the effect of HMTM, given alone or in combination with the acetylcholinesterase inhibitor, rivastigmine, at the level of expression of selected pre-synaptic proteins (syntaxin-1; SNAP-25, VAMP-2, synaptophysin-1, synapsin-1, α-synuclein) in brain tissue harvested from tau-transgenic Line 1 (L1) and wild-type mice using immunohistochemistry. L1 mice overexpress the tau-core unit that induces tau aggregation and results in an AD-like phenotype. Synaptic proteins were lower in hippocampus and cortex but greater in basal forebrain regions in L1 compared to wild-type mice. HMTM partially normalised the expression pattern of several of these proteins in basal forebrain. This effect was diminished when HMTM was administered in combination with rivastigmine, where mean protein expression seemed supressed. This was further confirmed by group-based correlation network analyses where important levels of co-expression correlations in basal forebrain regions were lost in L1 mice and partially re-established when HMTM was given alone but not in combination with rivastigmine. These data indicate a reduction in pharmacological activity of HMTM when given as an add-on therapy, a result that is consistent with the responses observed in the clinic. Attenuation of the therapeutic effects of HMTM by cholinergic treatments may have important implications for other potential AD therapies.
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Affiliation(s)
- Karima Schwab
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK; Institute of Pharmacology, Charité - Universitätsmedizin Berlin, Hessische Str. 3-4, Berlin 10115, Germany
| | - Dilyara Lauer
- Institute of Pharmacology, Charité - Universitätsmedizin Berlin, Hessische Str. 3-4, Berlin 10115, Germany
| | - Mandy Magbagbeolu
- Institute of Pharmacology, Charité - Universitätsmedizin Berlin, Hessische Str. 3-4, Berlin 10115, Germany
| | - Franz Theuring
- Institute of Pharmacology, Charité - Universitätsmedizin Berlin, Hessische Str. 3-4, Berlin 10115, Germany
| | - Anna Gasiorowska
- Clinical and Research Department of Applied Physiology, Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw 02-106, Poland
| | - Maciej Zadrozny
- Clinical and Research Department of Applied Physiology, Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw 02-106, Poland
| | - Charles R Harrington
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK; TauRx Therapeutics Ltd., 395 King Street, Aberdeen AB24 5RP, UK
| | - Claude M Wischik
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK; TauRx Therapeutics Ltd., 395 King Street, Aberdeen AB24 5RP, UK
| | - Grażyna Niewiadomska
- Clinical and Research Department of Applied Physiology, Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw 02-106, Poland
| | - Gernot Riedel
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK.
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2
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Paulussen I, Beckert H, Musial TF, Gschossmann LJ, Wolf J, Schmitt M, Clasadonte J, Mairet-Coello G, Wolff C, Schoch S, Dietrich D. SV2B defines a subpopulation of synaptic vesicles. J Mol Cell Biol 2024; 15:mjad054. [PMID: 37682518 PMCID: PMC11184983 DOI: 10.1093/jmcb/mjad054] [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: 08/25/2022] [Revised: 04/03/2023] [Accepted: 09/07/2023] [Indexed: 09/09/2023] Open
Abstract
Synaptic vesicles can undergo several modes of exocytosis, endocytosis, and trafficking within individual synapses, and their fates may be linked to different vesicular protein compositions. Here, we mapped the intrasynaptic distribution of the synaptic vesicle proteins SV2B and SV2A in glutamatergic synapses of the hippocampus using three-dimensional electron microscopy. SV2B was almost completely absent from docked vesicles and a distinct cluster of vesicles found near the active zone. In contrast, SV2A was found in all domains of the synapse and was slightly enriched near the active zone. SV2B and SV2A were found on the membrane in the peri-active zone, suggesting the recycling from both clusters of vesicles. SV2B knockout mice displayed an increased seizure induction threshold only in a model employing high-frequency stimulation. Our data show that glutamatergic synapses generate molecularly distinct populations of synaptic vesicles and are able to maintain them at steep spatial gradients. The almost complete absence of SV2B from vesicles at the active zone of wildtype mice may explain why SV2A has been found more important for vesicle release.
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Affiliation(s)
- Isabelle Paulussen
- Synaptic Neuroscience Team, Department of Neurosurgery, University Hospital Bonn, Bonn 53127, Germany
- Synaptic Neuroscience Team, Department of Neuropathology, University Hospital Bonn, Bonn 53127, Germany
| | - Hannes Beckert
- Microscopy Core Facility, Medical Faculty, University of Bonn, Bonn 53127, Germany
| | - Timothy F Musial
- Microscopy Core Facility, Medical Faculty, University of Bonn, Bonn 53127, Germany
| | - Lena J Gschossmann
- Synaptic Neuroscience Team, Department of Neurosurgery, University Hospital Bonn, Bonn 53127, Germany
- Synaptic Neuroscience Team, Department of Neuropathology, University Hospital Bonn, Bonn 53127, Germany
| | - Julia Wolf
- Synaptic Neuroscience Team, Department of Neurosurgery, University Hospital Bonn, Bonn 53127, Germany
- Synaptic Neuroscience Team, Department of Neuropathology, University Hospital Bonn, Bonn 53127, Germany
| | | | | | | | | | - Susanne Schoch
- Synaptic Neuroscience Team, Department of Neuropathology, University Hospital Bonn, Bonn 53127, Germany
| | - Dirk Dietrich
- Synaptic Neuroscience Team, Department of Neurosurgery, University Hospital Bonn, Bonn 53127, Germany
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3
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Parisi MJ, Aimino MA, Mosca TJ. A conditional strategy for cell-type-specific labeling of endogenous excitatory synapses in Drosophila. CELL REPORTS METHODS 2023; 3:100477. [PMID: 37323572 PMCID: PMC10261928 DOI: 10.1016/j.crmeth.2023.100477] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 02/28/2023] [Accepted: 04/19/2023] [Indexed: 06/17/2023]
Abstract
Chemical neurotransmission occurs at specialized contacts where neurotransmitter release machinery apposes neurotransmitter receptors to underlie circuit function. A series of complex events underlies pre- and postsynaptic protein recruitment to neuronal connections. To better study synaptic development in individual neurons, we need cell-type-specific strategies to visualize endogenous synaptic proteins. Although presynaptic strategies exist, postsynaptic proteins remain less studied because of a paucity of cell-type-specific reagents. To study excitatory postsynapses with cell-type specificity, we engineered dlg1[4K], a conditionally labeled marker of Drosophila excitatory postsynaptic densities. With binary expression systems, dlg1[4K] labels central and peripheral postsynapses in larvae and adults. Using dlg1[4K], we find that distinct rules govern postsynaptic organization in adult neurons, multiple binary expression systems can concurrently label pre- and postsynapse in a cell-type-specific manner, and neuronal DLG1 can sometimes localize presynaptically. These results validate our strategy for conditional postsynaptic labeling and demonstrate principles of synaptic organization.
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Affiliation(s)
- Michael J. Parisi
- Department of Neuroscience, Vickie and Jack Farber Institute of Neuroscience, Thomas Jefferson University, Bluemle Life Sciences Building, Philadelphia, PA 19107, USA
| | - Michael A. Aimino
- Department of Neuroscience, Vickie and Jack Farber Institute of Neuroscience, Thomas Jefferson University, Bluemle Life Sciences Building, Philadelphia, PA 19107, USA
| | - Timothy J. Mosca
- Department of Neuroscience, Vickie and Jack Farber Institute of Neuroscience, Thomas Jefferson University, Bluemle Life Sciences Building, Philadelphia, PA 19107, USA
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4
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Hu P, Leyton L, Hagood JS, Barker TH. Thy-1-Integrin Interactions in cis and Trans Mediate Distinctive Signaling. Front Cell Dev Biol 2022; 10:928510. [PMID: 35733855 PMCID: PMC9208718 DOI: 10.3389/fcell.2022.928510] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 05/23/2022] [Indexed: 12/04/2022] Open
Abstract
Thy-1 is a cell surface glycosylphosphatidylinositol (GPI)-anchored glycoprotein that bears a broad mosaic of biological roles across various cell types. Thy-1 displays strong physiological and pathological implications in development, cancer, immunity, and tissue fibrosis. Quite uniquely, Thy-1 is capable of mediating integrin-related signaling through direct trans- and cis-interaction with integrins. Both interaction types have shown distinctive roles, even when interacting with the same type of integrin, where binding in trans or in cis often yields divergent signaling events. In this review, we will revisit recent progress and discoveries of Thy-1–integrin interactions in trans and in cis, highlight their pathophysiological consequences and explore other potential binding partners of Thy-1 within the integrin regulation/signaling paradigm.
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Affiliation(s)
- Ping Hu
- Department of Biomedical Engineering, School of Engineering and Applied Science, University of Virginia, Charlottesville, VA, United States
| | - Lisette Leyton
- Cellular Communication Laboratory, Program of Cellular and Molecular Biology, Center for Studies on Exercise, Metabolism and Cancer (CEMC), Faculty of Medicine, Universidad de Chile, Santiago, Chile
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Chemical and Pharmaceutical Sciences and Faculty of Medicine, Universidad de Chile and Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago, Chile
| | - James S. Hagood
- Department of Pediatrics, Division of Pulmonology, School of Medicine, University of North Carolina, Chapel Hill, NC, United States
- Program for Rare and Interstitial Lung Disease, School of Medicine, University of North Carolina, Chapel Hill, NC, United States
| | - Thomas H. Barker
- Department of Biomedical Engineering, School of Engineering and Applied Science, University of Virginia, Charlottesville, VA, United States
- *Correspondence: Thomas H. Barker,
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5
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Gorniak-Walas M, Nizinska K, Lukasiuk K. Cloning and Functional Analysis of Rat Tweety-Homolog 1 Gene Promoter. Neurochem Res 2021; 46:2463-2472. [PMID: 34173119 PMCID: PMC8302521 DOI: 10.1007/s11064-021-03374-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 06/06/2021] [Accepted: 06/08/2021] [Indexed: 11/06/2022]
Abstract
Tweety-homolog 1 protein (Ttyh1) is abundantly expressed in neurons in the healthy brain, and its expression is induced under pathological conditions. In hippocampal neurons in vitro, Ttyh1 was implicated in the regulation of primary neuron morphology. However, the mechanisms that underlie transcriptional regulation of the Ttyh1 gene in neurons remain elusive. The present study sought to identify the promoter of the Ttyh1 gene and functionally characterize cis-regulatory elements that are potentially involved in the transcriptional regulation of Ttyh1 expression in rat dissociated hippocampal neurons in vitro. We cloned a 592 bp rat Ttyh1 promoter sequence and designed deletion constructs of the transcription factors specificity protein 1 (Sp1), E2F transcription factor 3 (E2f3), and achaete-scute homolog 1 (Ascl1) that were fused upstream of a luciferase reporter gene in pGL4.10[luc2]. The luciferase reporter gene assay showed the possible involvement of Ascl1, Sp1, and responsive cis-regulatory elements in Ttyh1 expression. These findings provide novel information about Ttyh1 gene regulation in neurons.
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Affiliation(s)
- Malgorzata Gorniak-Walas
- Laboratory of Epileptogenesis, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, 02-093, Warsaw, Poland
| | - Karolina Nizinska
- Laboratory of Epileptogenesis, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, 02-093, Warsaw, Poland
| | - Katarzyna Lukasiuk
- Laboratory of Epileptogenesis, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, 02-093, Warsaw, Poland.
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6
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O'Neil SD, Rácz B, Brown WE, Gao Y, Soderblom EJ, Yasuda R, Soderling SH. Action potential-coupled Rho GTPase signaling drives presynaptic plasticity. eLife 2021; 10:63756. [PMID: 34269176 PMCID: PMC8285108 DOI: 10.7554/elife.63756] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 07/06/2021] [Indexed: 12/30/2022] Open
Abstract
In contrast to their postsynaptic counterparts, the contributions of activity-dependent cytoskeletal signaling to presynaptic plasticity remain controversial and poorly understood. To identify and evaluate these signaling pathways, we conducted a proteomic analysis of the presynaptic cytomatrix using in vivo biotin identification (iBioID). The resultant proteome was heavily enriched for actin cytoskeleton regulators, including Rac1, a Rho GTPase that activates the Arp2/3 complex to nucleate branched actin filaments. Strikingly, we find Rac1 and Arp2/3 are closely associated with synaptic vesicle membranes in adult mice. Using three independent approaches to alter presynaptic Rac1 activity (genetic knockout, spatially restricted inhibition, and temporal optogenetic manipulation), we discover that this pathway negatively regulates synaptic vesicle replenishment at both excitatory and inhibitory synapses, bidirectionally sculpting short-term synaptic depression. Finally, we use two-photon fluorescence lifetime imaging to show that presynaptic Rac1 activation is coupled to action potentials by voltage-gated calcium influx. Thus, this study uncovers a previously unrecognized mechanism of actin-regulated short-term presynaptic plasticity that is conserved across excitatory and inhibitory terminals. It also provides a new proteomic framework for better understanding presynaptic physiology, along with a blueprint of experimental strategies to isolate the presynaptic effects of ubiquitously expressed proteins.
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Affiliation(s)
| | - Bence Rácz
- Department of Anatomy and Histology, University of Veterinary Medicine, Budapest, Hungary
| | - Walter Evan Brown
- Department of Cell Biology, Duke University Medical Center, Durham, United States
| | - Yudong Gao
- Department of Cell Biology, Duke University Medical Center, Durham, United States
| | - Erik J Soderblom
- Department of Cell Biology, Duke University Medical Center, Durham, United States.,Proteomics and Metabolomics Shared Resource and Center for Genomic and Computational Biology, Duke University Medical Center, Durham, United States
| | - Ryohei Yasuda
- Max Planck Florida Institute for Neuroscience, Jupiter, United States
| | - Scott H Soderling
- Department of Neurobiology, Duke University Medical Center, Durham, United States.,Department of Cell Biology, Duke University Medical Center, Durham, United States
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7
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Nalamalapu RR, Yue M, Stone AR, Murphy S, Saha MS. The tweety Gene Family: From Embryo to Disease. Front Mol Neurosci 2021; 14:672511. [PMID: 34262434 PMCID: PMC8273234 DOI: 10.3389/fnmol.2021.672511] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 05/18/2021] [Indexed: 12/31/2022] Open
Abstract
The tweety genes encode gated chloride channels that are found in animals, plants, and even simple eukaryotes, signifying their deep evolutionary origin. In vertebrates, the tweety gene family is highly conserved and consists of three members—ttyh1, ttyh2, and ttyh3—that are important for the regulation of cell volume. While research has elucidated potential physiological functions of ttyh1 in neural stem cell maintenance, proliferation, and filopodia formation during neural development, the roles of ttyh2 and ttyh3 are less characterized, though their expression patterns during embryonic and fetal development suggest potential roles in the development of a wide range of tissues including a role in the immune system in response to pathogen-associated molecules. Additionally, members of the tweety gene family have been implicated in various pathologies including cancers, particularly pediatric brain tumors, and neurodegenerative diseases such as Alzheimer’s and Parkinson’s disease. Here, we review the current state of research using information from published articles and open-source databases on the tweety gene family with regard to its structure, evolution, expression during development and adulthood, biochemical and cellular functions, and role in human disease. We also identify promising areas for further research to advance our understanding of this important, yet still understudied, family of genes.
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Affiliation(s)
- Rithvik R Nalamalapu
- Department of Biology, College of William and Mary, Williamsburg, VA, United States
| | - Michelle Yue
- Department of Biology, College of William and Mary, Williamsburg, VA, United States
| | - Aaron R Stone
- Department of Biology, College of William and Mary, Williamsburg, VA, United States
| | - Samantha Murphy
- Department of Biology, College of William and Mary, Williamsburg, VA, United States
| | - Margaret S Saha
- Department of Biology, College of William and Mary, Williamsburg, VA, United States
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8
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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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9
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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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10
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Xu Y, Song X, Wang D, Wang Y, Li P, Li J. Proteomic insights into synaptic signaling in the brain: the past, present and future. Mol Brain 2021; 14:37. [PMID: 33596935 PMCID: PMC7888154 DOI: 10.1186/s13041-021-00750-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 02/09/2021] [Indexed: 12/29/2022] Open
Abstract
Chemical synapses in the brain connect neurons to form neural circuits, providing the structural and functional bases for neural communication. Disrupted synaptic signaling is closely related to a variety of neurological and psychiatric disorders. In the past two decades, proteomics has blossomed as a versatile tool in biological and biomedical research, rendering a wealth of information toward decoding the molecular machinery of life. There is enormous interest in employing proteomic approaches for the study of synapses, and substantial progress has been made. Here, we review the findings of proteomic studies of chemical synapses in the brain, with special attention paid to the key players in synaptic signaling, i.e., the synaptic protein complexes and their post-translational modifications. Looking toward the future, we discuss the technological advances in proteomics such as data-independent acquisition mass spectrometry (DIA-MS), cross-linking in combination with mass spectrometry (CXMS), and proximity proteomics, along with their potential to untangle the mystery of how the brain functions at the molecular level. Last but not least, we introduce the newly developed synaptomic methods. These methods and their successful applications marked the beginnings of the synaptomics era.
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Affiliation(s)
- Yalan Xu
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, Medical College, Qingdao University, Qingdao, 266021, China
| | - Xiuyue Song
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, Medical College, Qingdao University, Qingdao, 266021, China
| | - Dong Wang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, Medical College, Qingdao University, Qingdao, 266021, China
| | - Yin Wang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, Medical College, Qingdao University, Qingdao, 266021, China
| | - Peifeng Li
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, Medical College, Qingdao University, Qingdao, 266021, China
| | - Jing Li
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, Medical College, Qingdao University, Qingdao, 266021, China.
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11
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Tweety-Homolog 1 Facilitates Pain via Enhancement of Nociceptor Excitability and Spinal Synaptic Transmission. Neurosci Bull 2020; 37:478-496. [PMID: 33355899 DOI: 10.1007/s12264-020-00617-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Accepted: 06/09/2020] [Indexed: 12/21/2022] Open
Abstract
Tweety-homolog 1 (Ttyh1) is expressed in neural tissue and has been implicated in the generation of several brain diseases. However, its functional significance in pain processing is not understood. By disrupting the gene encoding Ttyh1, we found a loss of Ttyh1 in nociceptors and their central terminals in Ttyh1-deficient mice, along with a reduction in nociceptor excitability and synaptic transmission at identified synapses between nociceptors and spinal neurons projecting to the periaqueductal grey (PAG) in the basal state. More importantly, the peripheral inflammation-evoked nociceptor hyperexcitability and spinal synaptic potentiation recorded in spinal-PAG projection neurons were compromised in Ttyh1-deficient mice. Analysis of the paired-pulse ratio and miniature excitatory postsynaptic currents indicated a role of presynaptic Ttyh1 from spinal nociceptor terminals in the regulation of neurotransmitter release. Interfering with Ttyh1 specifically in nociceptors produces a comparable pain relief. Thus, in this study we demonstrated that Ttyh1 is a critical determinant of acute nociception and pain sensitization caused by peripheral inflammation.
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12
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Boll I, Jensen P, Schwämmle V, Larsen MR. Depolarization-dependent Induction of Site-specific Changes in Sialylation on N-linked Glycoproteins in Rat Nerve Terminals. Mol Cell Proteomics 2020; 19:1418-1435. [PMID: 32518069 PMCID: PMC8143646 DOI: 10.1074/mcp.ra119.001896] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 06/08/2020] [Indexed: 12/11/2022] Open
Abstract
Synaptic transmission leading to release of neurotransmitters in the nervous system is a fast and highly dynamic process. Previously, protein interaction and phosphorylation have been thought to be the main regulators of synaptic transmission. Here we show that sialylation of N-linked glycosylation is a novel potential modulator of neurotransmitter release mechanisms by investigating depolarization-dependent changes of formerly sialylated N-linked glycopeptides. We suggest that negatively charged sialic acids can be modulated, similarly to phosphorylation, by the action of sialyltransferases and sialidases thereby changing local structure and function of membrane glycoproteins. We characterized site-specific alteration in sialylation on N-linked glycoproteins in isolated rat nerve terminals after brief depolarization using quantitative sialiomics. We identified 1965 formerly sialylated N-linked glycosites in synaptic proteins and found that the abundances of 430 glycosites changed after 5 s depolarization. We observed changes on essential synaptic proteins such as synaptic vesicle proteins, ion channels and transporters, neurotransmitter receptors and cell adhesion molecules. This study is to our knowledge the first to describe ultra-fast site-specific modulation of the sialiome after brief stimulation of a biological system.
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Affiliation(s)
- Inga Boll
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense M, Denmark
| | - Pia Jensen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense M, Denmark
| | - Veit Schwämmle
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense M, Denmark
| | - Martin R Larsen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense M, Denmark.
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13
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Ahmad F, Liu P. Synaptosome as a tool in Alzheimer's disease research. Brain Res 2020; 1746:147009. [PMID: 32659233 DOI: 10.1016/j.brainres.2020.147009] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 06/21/2020] [Accepted: 07/04/2020] [Indexed: 12/29/2022]
Abstract
Synapse dysfunction is an integral feature of Alzheimer's disease (AD) pathophysiology. In fact, prodromal manifestation of structural and functional deficits in synapses much prior to appearance of overt pathological hallmarks of the disease indicates that AD might be considered as a degenerative disorder of the synapses. Several research instruments and techniques have allowed us to study synaptic function and plasticity and their alterations in pathological conditions, such as AD. One such tool is the biochemically isolated preparations of detached and resealed synaptic terminals, the "synaptosomes". Because of the preservation of many of the physiological processes such as metabolic and enzymatic activities, synaptosomes have proved to be an indispensable ex vivo model system to study synapse physiology both when isolated from fresh or cryopreserved tissues, and from animal or human post-mortem tissues. This model system has been tremendously successful in the case of post-mortem tissues because of their accessibility relative to acute brain slices or cultures. The current review details the use of synaptosomes in AD research and its potential as a valuable tool in furthering our understanding of the pathogenesis and in devising and testing of therapeutic strategies for the disease.
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Affiliation(s)
- Faraz Ahmad
- Department of Anatomy, School of Biomedical Sciences, Brain Research New Zealand, University of Otago, Dunedin, New Zealand.
| | - Ping Liu
- Department of Anatomy, School of Biomedical Sciences, Brain Research New Zealand, University of Otago, Dunedin, New Zealand
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14
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Zakyrjanova GF, Gilmutdinov AI, Tsentsevitsky AN, Petrov AM. Olesoxime, a cholesterol-like neuroprotectant restrains synaptic vesicle exocytosis in the mice motor nerve terminals: Possible role of VDACs. Biochim Biophys Acta Mol Cell Biol Lipids 2020; 1865:158739. [PMID: 32428575 DOI: 10.1016/j.bbalip.2020.158739] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 05/11/2020] [Accepted: 05/13/2020] [Indexed: 12/13/2022]
Abstract
Olesoxime is a cholesterol-like neuroprotective compound that targets to mitochondrial voltage dependent anion channels (VDACs). VDACs were also found in the plasma membrane and highly expressed in the presynaptic compartment. Here, we studied the effects of olesoxime and VDAC inhibitors on neurotransmission in the mouse neuromuscular junction. Electrophysiological analysis revealed that olesoxime suppressed selectively evoked neurotransmitter release in response to a single stimulus and 20 Hz activity. Also olesoxime decreased the rate of FM1-43 dye loss (an indicator of synaptic vesicle exocytosis) at low frequency stimulation and 20 Hz. Furthermore, an increase in extracellular Cl- enhanced the action of olesoxime on the exocytosis and olesoxime increased intracellular Cl- levels. The effects of olesoxime on the evoked synaptic vesicle exocytosis and [Cl-]i were blocked by membrane-permeable and impermeable VDAC inhibitors. Immunofluorescent labeling pointed on the presence of VDACs on the synaptic membranes. Rotenone-induced mitochondrial dysfunction perturbed the exocytotic release of FM1-43 and cell-permeable VDAC inhibitor (but not olesoxime or impermeable VDAC inhibitor) partially mitigated the rotenone-driven alterations in the FM1-43 unloading and mitochondrial superoxide production. Thus, olesoxime restrains neurotransmission by acting on plasmalemmal VDACs whose activation can limit synaptic vesicle exocytosis probably via increasing anion flux into the nerve terminals.
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Affiliation(s)
- Guzalia F Zakyrjanova
- Laboratory of Biophysics of Synaptic Processes, Kazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center of RAS", 2/31 Lobachevsky Street, box 30, Kazan 420111, Russia; Institute of Neuroscience, Kazan State Medial University, 49 Butlerova Street, Kazan 420012, Russia
| | - Amir I Gilmutdinov
- Laboratory of Biophysics of Synaptic Processes, Kazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center of RAS", 2/31 Lobachevsky Street, box 30, Kazan 420111, Russia
| | - Andrey N Tsentsevitsky
- Laboratory of Biophysics of Synaptic Processes, Kazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center of RAS", 2/31 Lobachevsky Street, box 30, Kazan 420111, Russia
| | - Alexey M Petrov
- Laboratory of Biophysics of Synaptic Processes, Kazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center of RAS", 2/31 Lobachevsky Street, box 30, Kazan 420111, Russia; Institute of Neuroscience, Kazan State Medial University, 49 Butlerova Street, Kazan 420012, Russia.
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15
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Koopmans F, van Nierop P, Andres-Alonso M, Byrnes A, Cijsouw T, Coba MP, Cornelisse LN, Farrell RJ, Goldschmidt HL, Howrigan DP, Hussain NK, Imig C, de Jong APH, Jung H, Kohansalnodehi M, Kramarz B, Lipstein N, Lovering RC, MacGillavry H, Mariano V, Mi H, Ninov M, Osumi-Sutherland D, Pielot R, Smalla KH, Tang H, Tashman K, Toonen RFG, Verpelli C, Reig-Viader R, Watanabe K, van Weering J, Achsel T, Ashrafi G, Asi N, Brown TC, De Camilli P, Feuermann M, Foulger RE, Gaudet P, Joglekar A, Kanellopoulos A, Malenka R, Nicoll RA, Pulido C, de Juan-Sanz J, Sheng M, Südhof TC, Tilgner HU, Bagni C, Bayés À, Biederer T, Brose N, Chua JJE, Dieterich DC, Gundelfinger ED, Hoogenraad C, Huganir RL, Jahn R, Kaeser PS, Kim E, Kreutz MR, McPherson PS, Neale BM, O'Connor V, Posthuma D, Ryan TA, Sala C, Feng G, Hyman SE, Thomas PD, Smit AB, Verhage M. SynGO: An Evidence-Based, Expert-Curated Knowledge Base for the Synapse. Neuron 2019; 103:217-234.e4. [PMID: 31171447 DOI: 10.1016/j.neuron.2019.05.002] [Citation(s) in RCA: 395] [Impact Index Per Article: 79.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 04/02/2019] [Accepted: 04/30/2019] [Indexed: 12/23/2022]
Abstract
Synapses are fundamental information-processing units of the brain, and synaptic dysregulation is central to many brain disorders ("synaptopathies"). However, systematic annotation of synaptic genes and ontology of synaptic processes are currently lacking. We established SynGO, an interactive knowledge base that accumulates available research about synapse biology using Gene Ontology (GO) annotations to novel ontology terms: 87 synaptic locations and 179 synaptic processes. SynGO annotations are exclusively based on published, expert-curated evidence. Using 2,922 annotations for 1,112 genes, we show that synaptic genes are exceptionally well conserved and less tolerant to mutations than other genes. Many SynGO terms are significantly overrepresented among gene variations associated with intelligence, educational attainment, ADHD, autism, and bipolar disorder and among de novo variants associated with neurodevelopmental disorders, including schizophrenia. SynGO is a public, universal reference for synapse research and an online analysis platform for interpretation of large-scale -omics data (https://syngoportal.org and http://geneontology.org).
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Affiliation(s)
- Frank Koopmans
- Department of Functional Genomics, CNCR, VU University and UMC Amsterdam, 1081 HV Amsterdam, the Netherlands; Department of Molecular and Cellular Neurobiology, CNCR, VU University and UMC Amsterdam, 1081 HV Amsterdam, the Netherlands
| | - Pim van Nierop
- Department of Molecular and Cellular Neurobiology, CNCR, VU University and UMC Amsterdam, 1081 HV Amsterdam, the Netherlands
| | - Maria Andres-Alonso
- RG Neuroplasticity, Leibniz Institute for Neurobiology, 39118 Magdeburg, Germany; Leibniz Group "Dendritic Organelles and Synaptic Function," ZMNH, University MC, Hamburg, 20251, Germany
| | - Andrea Byrnes
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Tony Cijsouw
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA 02111, USA
| | - Marcelo P Coba
- Zilkha Neurogenetic Institute and Department of Psychiatry and Behavioral Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA 90333, USA
| | - L Niels Cornelisse
- Department of Functional Genomics, CNCR, VU University and UMC Amsterdam, 1081 HV Amsterdam, the Netherlands
| | - Ryan J Farrell
- Department of Biochemistry, Weill Cornell Medicine, New York, NY 10065, USA
| | - Hana L Goldschmidt
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Daniel P Howrigan
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Natasha K Hussain
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Kavli Neuroscience Discovery Institute, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Cordelia Imig
- Department of Molecular Neurobiology, Max Planck Institute of Experimental Medicine, 37075 Göttingen, Germany
| | - Arthur P H de Jong
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Hwajin Jung
- Center for Synaptic Brain Dysfunctions, IBS, and Department of Biological Sciences, KAIST, Daejeon 34141, South Korea
| | - Mahdokht Kohansalnodehi
- Department of Neurobiology, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany
| | - Barbara Kramarz
- Functional Gene Annotation, Institute of Cardiovascular Science, UCL, London WC1E 6JF, UK
| | - Noa Lipstein
- Department of Molecular Neurobiology, Max Planck Institute of Experimental Medicine, 37075 Göttingen, Germany
| | - Ruth C Lovering
- Functional Gene Annotation, Institute of Cardiovascular Science, UCL, London WC1E 6JF, UK
| | - Harold MacGillavry
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, 3584 CH Utrecht, the Netherlands
| | - Vittoria Mariano
- Department of Fundamental Neurosciences, University of Lausanne, 1006 Lausanne, Switzerland; Department of Biomedicine and Prevention, University of Rome Tor Vergata, 00133 Rome, Italy
| | - Huaiyu Mi
- Division of Bioinformatics, Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Momchil Ninov
- Department of Neurobiology, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany
| | - David Osumi-Sutherland
- European Bioinformatics Institute (EMBL-EBI), Wellcome Trust Genome Campus, Cambridge CB10 1SD, UK
| | - Rainer Pielot
- Leibniz Institute for Neurobiology, CBBS and Medical Faculty, Otto von Guericke University, 39120 Magdeburg, Germany
| | - Karl-Heinz Smalla
- Leibniz Institute for Neurobiology, CBBS and Medical Faculty, Otto von Guericke University, 39120 Magdeburg, Germany
| | - Haiming Tang
- Division of Bioinformatics, Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Katherine Tashman
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Ruud F G Toonen
- Department of Functional Genomics, CNCR, VU University and UMC Amsterdam, 1081 HV Amsterdam, the Netherlands
| | - Chiara Verpelli
- CNR Neuroscience Institute Milan and Department of Biotechnology and Translational Medicine, University of Milan, 20129 Milan, Italy
| | - Rita Reig-Viader
- Molecular Physiology of the Synapse Laboratory, Biomedical Research Institute Sant Pau, 08025 Barcelona, Spain; Universitat Autònoma de Barcelona, 08193 Bellaterra, Cerdanyola del Vallès, Spain
| | - Kyoko Watanabe
- Department Complex Trait Genetics, CNCR, Neuroscience Campus Amsterdam, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands; Department of Clinical Genetics, UMC Amsterdam, 1081 HV Amsterdam, the Netherlands
| | - Jan van Weering
- Department of Functional Genomics, CNCR, VU University and UMC Amsterdam, 1081 HV Amsterdam, the Netherlands
| | - Tilmann Achsel
- Department of Fundamental Neurosciences, University of Lausanne, 1006 Lausanne, Switzerland; Department of Biomedicine and Prevention, University of Rome Tor Vergata, 00133 Rome, Italy
| | - Ghazaleh Ashrafi
- Department of Biochemistry, Weill Cornell Medicine, New York, NY 10065, USA
| | - Nimra Asi
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Tyler C Brown
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Pietro De Camilli
- Departments of Neuroscience and Cell Biology, HHMI, Kavli Institute for Neuroscience, Yale University School of Medicine, 295 Congress Avenue, New Haven, CT 06510, USA
| | - Marc Feuermann
- SIB Swiss Institute of Bioinformatics, Centre Medical Universitaire, 1 rue Michel Servet, 1211 Geneva 4, Switzerland
| | - Rebecca E Foulger
- Functional Gene Annotation, Institute of Cardiovascular Science, UCL, London WC1E 6JF, UK
| | - Pascale Gaudet
- SIB Swiss Institute of Bioinformatics, Centre Medical Universitaire, 1 rue Michel Servet, 1211 Geneva 4, Switzerland
| | - Anoushka Joglekar
- Brain and Mind Research Institute and Center for Neurogenetics, Weill Cornell Medicine, New York, NY, USA
| | - Alexandros Kanellopoulos
- Department of Fundamental Neurosciences, University of Lausanne, 1006 Lausanne, Switzerland; Department of Biomedicine and Prevention, University of Rome Tor Vergata, 00133 Rome, Italy
| | - Robert Malenka
- Nancy Pritzker Laboratory, Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA
| | - Roger A Nicoll
- Departments of Cellular and Molecular Pharmacology and Physiology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Camila Pulido
- Department of Biochemistry, Weill Cornell Medicine, New York, NY 10065, USA
| | - Jaime de Juan-Sanz
- Department of Biochemistry, Weill Cornell Medicine, New York, NY 10065, USA
| | - Morgan Sheng
- Department of Neuroscience, Genentech, South San Francisco, CA 94080, USA
| | - Thomas C Südhof
- Department of Molecular and Cellular Physiology, Howard Hughes Medical Institute, Stanford University, Stanford, CA 94305, USA
| | - Hagen U Tilgner
- Brain and Mind Research Institute and Center for Neurogenetics, Weill Cornell Medicine, New York, NY, USA
| | - Claudia Bagni
- Department of Fundamental Neurosciences, University of Lausanne, 1006 Lausanne, Switzerland; Department of Biomedicine and Prevention, University of Rome Tor Vergata, 00133 Rome, Italy
| | - Àlex Bayés
- Molecular Physiology of the Synapse Laboratory, Biomedical Research Institute Sant Pau, 08025 Barcelona, Spain; Universitat Autònoma de Barcelona, 08193 Bellaterra, Cerdanyola del Vallès, Spain
| | - Thomas Biederer
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA 02111, USA
| | - Nils Brose
- Department of Molecular Neurobiology, Max Planck Institute of Experimental Medicine, 37075 Göttingen, Germany
| | - John Jia En Chua
- Department of Physiology, Yong Loo Lin School of Medicine and Neurobiology/Ageing Program, Life Sciences Institute, National University of Singapore and Institute of Molecular and Cell Biology, A(∗)STAR, Singapore, Singapore
| | - Daniela C Dieterich
- Leibniz Institute for Neurobiology, CBBS and Medical Faculty, Otto von Guericke University, 39120 Magdeburg, Germany
| | - Eckart D Gundelfinger
- Leibniz Institute for Neurobiology, CBBS and Medical Faculty, Otto von Guericke University, 39120 Magdeburg, Germany
| | - Casper Hoogenraad
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, 3584 CH Utrecht, the Netherlands
| | - Richard L Huganir
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Kavli Neuroscience Discovery Institute, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Reinhard Jahn
- Department of Neurobiology, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany
| | - Pascal S Kaeser
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Eunjoon Kim
- Center for Synaptic Brain Dysfunctions, IBS, and Department of Biological Sciences, KAIST, Daejeon 34141, South Korea
| | - Michael R Kreutz
- RG Neuroplasticity, Leibniz Institute for Neurobiology, 39118 Magdeburg, Germany; Leibniz Group "Dendritic Organelles and Synaptic Function," ZMNH, University MC, Hamburg, 20251, Germany
| | - Peter S McPherson
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC H3A 2B4, Canada
| | - Ben M Neale
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Vincent O'Connor
- Biological Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Danielle Posthuma
- Department Complex Trait Genetics, CNCR, Neuroscience Campus Amsterdam, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands; Department of Clinical Genetics, UMC Amsterdam, 1081 HV Amsterdam, the Netherlands
| | - Timothy A Ryan
- Department of Biochemistry, Weill Cornell Medicine, New York, NY 10065, USA
| | - Carlo Sala
- CNR Neuroscience Institute Milan and Department of Biotechnology and Translational Medicine, University of Milan, 20129 Milan, Italy
| | - Guoping Feng
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Steven E Hyman
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Paul D Thomas
- Division of Bioinformatics, Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - August B Smit
- Department of Molecular and Cellular Neurobiology, CNCR, VU University and UMC Amsterdam, 1081 HV Amsterdam, the Netherlands.
| | - Matthijs Verhage
- Department of Functional Genomics, CNCR, VU University and UMC Amsterdam, 1081 HV Amsterdam, the Netherlands.
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16
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Rossetto O, Pirazzini M, Lista F, Montecucco C. The role of the single interchains disulfide bond in tetanus and botulinum neurotoxins and the development of antitetanus and antibotulism drugs. Cell Microbiol 2019; 21:e13037. [PMID: 31050145 PMCID: PMC6899712 DOI: 10.1111/cmi.13037] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 04/18/2019] [Accepted: 04/30/2019] [Indexed: 01/02/2023]
Abstract
A large number of bacterial toxins consist of active and cell binding protomers linked by an interchain disulfide bridge. The largest family of such disulfide‐bridged exotoxins is that of the clostridial neurotoxins that consist of two chains and comprise the tetanus neurotoxins causing tetanus and the botulinum neurotoxins causing botulism. Reduction of the interchain disulfide abolishes toxicity, and we discuss the experiments that revealed the role of this structural element in neuronal intoxication. The redox couple thioredoxin reductase–thioredoxin (TrxR‐Trx) was identified as the responsible for reduction of this disulfide occurring on the cytosolic surface of synaptic vesicles. We then discuss the very relevant finding that drugs that inhibit TrxR‐Trx also prevent botulism. On this basis, we propose that ebselen and PX‐12, two TrxR‐Trx specific drugs previously used in clinical trials in humans, satisfy all the requirements for clinical tests aiming at evaluating their capacity to effectively counteract human and animal botulism arising from intestinal toxaemias such as infant botulism.
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Affiliation(s)
- Ornella Rossetto
- Dipartimento di Scienze Biomediche, Università di Padova, Padua, Italy
| | - Marco Pirazzini
- Dipartimento di Scienze Biomediche, Università di Padova, Padua, Italy
| | - Florigio Lista
- Sezione di Istologia e Biologia Molecolare, Centro di ricerca Medica e Veterinaria del Ministero della Difesa, Rome, Italy
| | - Cesare Montecucco
- Dipartimento di Scienze Biomediche, Università di Padova, Padua, Italy.,Istituto Neuroscienze del CNR, Università di Padova, Padua, Italy
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17
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Held RG, Kaeser PS. ELKS active zone proteins as multitasking scaffolds for secretion. Open Biol 2019; 8:rsob.170258. [PMID: 29491150 PMCID: PMC5830537 DOI: 10.1098/rsob.170258] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2017] [Accepted: 02/06/2018] [Indexed: 12/18/2022] Open
Abstract
Synaptic vesicle exocytosis relies on the tethering of release ready vesicles close to voltage-gated Ca2+ channels and specific lipids at the future site of fusion. This enables rapid and efficient neurotransmitter secretion during presynaptic depolarization by an action potential. Extensive research has revealed that this tethering is mediated by an active zone, a protein dense structure that is attached to the presynaptic plasma membrane and opposed to postsynaptic receptors. Although roles of individual active zone proteins in exocytosis are in part understood, the molecular mechanisms that hold the protein scaffold at the active zone together and link it to the presynaptic plasma membrane have remained unknown. This is largely due to redundancy within and across scaffolding protein families at the active zone. Recent studies, however, have uncovered that ELKS proteins, also called ERC, Rab6IP2 or CAST, act as active zone scaffolds redundant with RIMs. This redundancy has led to diverse synaptic phenotypes in studies of ELKS knockout mice, perhaps because different synapses rely to a variable extent on scaffolding redundancy. In this review, we first evaluate the need for presynaptic scaffolding, and we then discuss how the diverse synaptic and non-synaptic functional roles of ELKS support the hypothesis that ELKS provides molecular scaffolding for organizing vesicle traffic at the presynaptic active zone and in other cellular compartments.
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Affiliation(s)
- Richard G Held
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Pascal S Kaeser
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
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18
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Lleó A, Núñez-Llaves R, Alcolea D, Chiva C, Balateu-Paños D, Colom-Cadena M, Gomez-Giro G, Muñoz L, Querol-Vilaseca M, Pegueroles J, Rami L, Lladó A, Molinuevo JL, Tainta M, Clarimón J, Spires-Jones T, Blesa R, Fortea J, Martínez-Lage P, Sánchez-Valle R, Sabidó E, Bayés À, Belbin O. Changes in Synaptic Proteins Precede Neurodegeneration Markers in Preclinical Alzheimer's Disease Cerebrospinal Fluid. Mol Cell Proteomics 2019; 18:546-560. [PMID: 30606734 PMCID: PMC6398205 DOI: 10.1074/mcp.ra118.001290] [Citation(s) in RCA: 102] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Indexed: 01/08/2023] Open
Abstract
A biomarker of synapse loss, an early event in Alzheimer's disease (AD) pathophysiology that precedes neuronal death and symptom onset, would be a much-needed prognostic biomarker. With direct access to the brain interstitial fluid, the cerebrospinal fluid (CSF) is a potential source of synapse-derived proteins. In this study, we aimed to identify and validate novel CSF biomarkers of synapse loss in AD. Discovery: Combining shotgun proteomics of the CSF with an exhaustive search of the literature and public databases, we identified 251 synaptic proteins, from which we selected 22 for further study. Verification: Twelve proteins were discarded because of poor detection by Selected Reaction Monitoring (SRM). We confirmed the specific expression of 9 of the remaining proteins (Calsynytenin-1, GluR2, GluR4, Neurexin-2A, Neurexin-3A, Neuroligin-2, Syntaxin-1B, Thy-1, Vamp-2) at the human synapse using Array Tomography microscopy and biochemical fractionation methods. Exploration: Using SRM, we monitored these 9 synaptic proteins (20 peptides) in a cohort of CSF from cognitively normal controls and subjects in the pre-clinical and clinical AD stages (n = 80). Compared with controls, peptides from 8 proteins were elevated 1.3 to 1.6-fold (p < 0.04) in prodromal AD patients. Validation: Elevated levels of a GluR4 peptide at the prodromal stage were replicated (1.3-fold, p = 0.04) in an independent cohort (n = 60). Moreover, 7 proteins were reduced at preclinical stage 1 (0.6 to 0.8-fold, p < 0.04), a finding that was replicated (0.7 to 0.8-fold, p < 0.05) for 6 proteins in a third cohort (n = 38). In a cross-cohort meta-analysis, 6 synaptic proteins (Calsyntenin-1, GluR4, Neurexin-2A, Neurexin-3A, Syntaxin-1B and Thy-1) were reduced 0.8-fold (p < 0.05) in preclinical AD, changes that precede clinical symptoms and CSF markers of neurodegeneration. Therefore, these proteins could have clinical value for assessing disease progression, especially in preclinical stages of AD.
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Affiliation(s)
- Alberto Lleó
- From the ‡Memory Unit, Neurology Department, Hospital de la Santa Creu i Sant Pau, 08025 Barcelona, Spain;
- §Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
| | - Raúl Núñez-Llaves
- §Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
- ¶Biomedical Research Institute Sant Pau (IIB Sant Pau), 08025Barcelona, Spain
| | - Daniel Alcolea
- From the ‡Memory Unit, Neurology Department, Hospital de la Santa Creu i Sant Pau, 08025 Barcelona, Spain
- §Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
| | - Cristina Chiva
- ‖Proteomics Unit, Center for Genomics Regulation, Barcelona Institute of Science and Technology, 08003 Barcelona
- **University Pompeu Fabra, 08003 Barcelona
| | | | - Martí Colom-Cadena
- §Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
- ¶Biomedical Research Institute Sant Pau (IIB Sant Pau), 08025Barcelona, Spain
| | - Gemma Gomez-Giro
- ¶Biomedical Research Institute Sant Pau (IIB Sant Pau), 08025Barcelona, Spain
| | - Laia Muñoz
- §Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
- ¶Biomedical Research Institute Sant Pau (IIB Sant Pau), 08025Barcelona, Spain
| | - Marta Querol-Vilaseca
- §Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
- ¶Biomedical Research Institute Sant Pau (IIB Sant Pau), 08025Barcelona, Spain
| | - Jordi Pegueroles
- §Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
- ¶Biomedical Research Institute Sant Pau (IIB Sant Pau), 08025Barcelona, Spain
| | - Lorena Rami
- ‡‡Alzheimer's Disease and Other Cognitive Disorders Unit, Neurology Department, Hospital Clínic-Institut d'Investigacions Biomediques August Pi i Sunyer (IDIBAPS), 08015 Barcelona, Spain
| | - Albert Lladó
- ‡‡Alzheimer's Disease and Other Cognitive Disorders Unit, Neurology Department, Hospital Clínic-Institut d'Investigacions Biomediques August Pi i Sunyer (IDIBAPS), 08015 Barcelona, Spain
| | - José L Molinuevo
- ‡‡Alzheimer's Disease and Other Cognitive Disorders Unit, Neurology Department, Hospital Clínic-Institut d'Investigacions Biomediques August Pi i Sunyer (IDIBAPS), 08015 Barcelona, Spain
| | - Mikel Tainta
- §§Department of Neurology, Center for Research and Advanced Therapies, CITA-Alzheimer Foundation, 20009 San Sebastian, Spain
- ¶¶Servicio de Neurologia, Organización Sanitaria Integrada Goierri-Alto Urola, Osakidetza, Zumárraga, España
| | - Jordi Clarimón
- §Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
- ¶Biomedical Research Institute Sant Pau (IIB Sant Pau), 08025Barcelona, Spain
| | - Tara Spires-Jones
- ‖‖Centre for Discovery Brain Sciences and UK Dementia Research Institute, University of Edinburgh EH8 9JZ, UK
| | - Rafael Blesa
- From the ‡Memory Unit, Neurology Department, Hospital de la Santa Creu i Sant Pau, 08025 Barcelona, Spain
- §Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
| | - Juan Fortea
- From the ‡Memory Unit, Neurology Department, Hospital de la Santa Creu i Sant Pau, 08025 Barcelona, Spain
- §Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
| | - Pablo Martínez-Lage
- §§Department of Neurology, Center for Research and Advanced Therapies, CITA-Alzheimer Foundation, 20009 San Sebastian, Spain
| | - Raquel Sánchez-Valle
- ‡‡Alzheimer's Disease and Other Cognitive Disorders Unit, Neurology Department, Hospital Clínic-Institut d'Investigacions Biomediques August Pi i Sunyer (IDIBAPS), 08015 Barcelona, Spain
| | - Eduard Sabidó
- ‖Proteomics Unit, Center for Genomics Regulation, Barcelona Institute of Science and Technology, 08003 Barcelona
- **University Pompeu Fabra, 08003 Barcelona
| | - Àlex Bayés
- ***Molecular Physiology of the Synapse Laboratory, Biomedical Research Institute Sant Pau (IIB Sant Pau), 08025, Barcelona, Spain
- ‡‡‡Universitat Autònoma de Barcelona, 08193 Bellaterra (Cerdanyola del Vallès), Spain
| | - Olivia Belbin
- §Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain;
- ¶Biomedical Research Institute Sant Pau (IIB Sant Pau), 08025Barcelona, Spain
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19
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LoPachin RM, Geohagen BC, Nordstroem LU. Mechanisms of soft and hard electrophile toxicities. Toxicology 2019; 418:62-69. [PMID: 30826385 DOI: 10.1016/j.tox.2019.02.005] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 01/24/2019] [Accepted: 02/10/2019] [Indexed: 12/21/2022]
Abstract
Electron-deficient chemicals (electrophiles) react with compounds that have one or more unshared valence electron pairs (nucleophiles). The resulting covalent reactions between electrophiles and nucleophiles (e.g., Michael addition, SN2 reactions) are important, not only to Organic Chemistry, but also to the fields of Molecular Biology and Toxicology. Specifically, covalent bond formation is the operational basis of many critically important cellular processes; e.g., enzyme function, neurotransmitter release, and membrane-vesicle fusion. Given this context it is understandable that these reactions are also relevant to Toxicology, since a significant number of xenobiotic chemicals are toxic electrophiles that can react with endogenous nucleophilic residues. Therefore, the purpose of this Review is to discuss electrophile-nucleophile chemistry as it pertains to cell injury and resulting organ toxicity. Our discussion will involve an introduction to the Hard and Soft, Acids and Bases (HSAB) theory of Pearson. The HSAB concept provides a framework for calculation of quantum chemical parameters that classify the electrophile and nucleophile covalent components according to their respective electronic nature (softness/hardness) and reactivity (electrophilicity/nucleophilicity). The calculated quantum indices in conjunction with corroborative in vivo, in chemico (cell free) and in vitro research can offer an illuminating approach to mechanistic discovery. Accordingly, we will provide examples that demonstrate how this approach has been used to discern mechanisms and sites of electrophile action.
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Affiliation(s)
- Richard M LoPachin
- Department of Anesthesiology, Montefiore Medical Center, Albert Einstein College of Medicine, 111 E. 210th St, Bronx NY 10467, United States.
| | - Brian C Geohagen
- Department of Anesthesiology, Montefiore Medical Center, Albert Einstein College of Medicine, 111 E. 210th St, Bronx NY 10467, United States
| | - Lars U Nordstroem
- The Chemical Synthesis & Biology Core Facility, Albert Einstein College of Medicine, Bronx, NY, United States
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20
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Ramos-Miguel A, Barakauskas V, Alamri J, Miyauchi M, Barr AM, Beasley CL, Rosoklija G, Mann JJ, Dwork AJ, Moradian A, Morin GB, Honer WG. The SNAP25 Interactome in Ventromedial Caudate in Schizophrenia Includes the Mitochondrial Protein ARF1. Neuroscience 2019; 420:97-111. [PMID: 30610939 DOI: 10.1016/j.neuroscience.2018.12.045] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 12/21/2018] [Accepted: 12/24/2018] [Indexed: 12/11/2022]
Abstract
Abnormalities of SNAP25 (synaptosome-associated protein 25) amount and protein-protein interactions occur in schizophrenia, and may contribute to abnormalities of neurotransmitter release in patients. However, presynaptic terminal function depends on multiple subcellular mechanisms, including energy provided by mitochondria. To explore the SNAP25 interactome in schizophrenia, we immunoprecipitated SNAP25 along with interacting proteins from the ventromedial caudate of 15 cases of schizophrenia and 13 controls. Proteins were identified with mass spectrometry-based proteomics. As well as 15 SNARE- (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) associated proteins, we identified 17 mitochondria-associated and four other proteins. The mitochondrial small GTPase ARF1 (ADP-ribosylation factor 1) was identified in eight schizophrenia SNAP25 immunoprecipitates and none from controls (P = 0.004). Although the ARF1-SNAP25 interaction may be increased, immunoblotting demonstrated 21% lower ARF1-21 (21 kiloDaltons) in schizophrenia samples (P = 0.04). In contrast, the mitochondrial protein UQCRC1 (ubiquinol-cytochrome c reductase core protein 1) did not differ. Lower ARF1-21 levels were associated with the previously reported increased SNAP25-syntaxin interaction in schizophrenia (r = -0.39, P = 0.04). Additional immunoprecipitation studies confirmed the ARF1-21-SNAP25 interaction, independent of UQCRC1. Both ARF1 and SNAP25 were localized to synaptosomes. Confocal microscopy demonstrated co-localization of ARF1 and SNAP25, and further suggested fivefold enrichment of ARF1 in synaptosomes containing an excitatory marker (vesicular glutamate transporter) compared with synaptosomes containing an inhibitory marker (vesicular GABA transporter). The present findings suggest an association between abnormalities of SNARE proteins involved with vesicular neurotransmission and the mitochondrial protein ARF1 that may contribute to the pathophysiology of schizophrenia.
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Affiliation(s)
- Alfredo Ramos-Miguel
- BC Mental Health and Addictions Research Institute, 938 West 28th Ave, Vancouver, BC V5Z 4H4, Canada; Department of Psychiatry, University of British Columbia, 2255 Wesbrook Mall, Vancouver, BC V6T 2A1, Canada; Department of Pharmacology, University of the Basque Country, Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM, Barrio Sarriena, s/n, 48940 Leioa, Biscay, Spain
| | - Vilte Barakauskas
- BC Mental Health and Addictions Research Institute, 938 West 28th Ave, Vancouver, BC V5Z 4H4, Canada; Department of Pathology and Laboratory Medicine, University of British Columbia, 2J9-4500 Oak St., Vancouver, BC V6H 3B1, Canada
| | - Jehan Alamri
- BC Mental Health and Addictions Research Institute, 938 West 28th Ave, Vancouver, BC V5Z 4H4, Canada
| | - Masatoshi Miyauchi
- BC Mental Health and Addictions Research Institute, 938 West 28th Ave, Vancouver, BC V5Z 4H4, Canada; Department of Psychiatry, University of British Columbia, 2255 Wesbrook Mall, Vancouver, BC V6T 2A1, Canada
| | - Alasdair M Barr
- BC Mental Health and Addictions Research Institute, 938 West 28th Ave, Vancouver, BC V5Z 4H4, Canada; Department of Anesthesiology, Pharmacology, & Therapeutics, University of British Columbia, 2176 Health Sciences Mall Vancouver, BC V6T 1Z3, Canada
| | - Clare L Beasley
- BC Mental Health and Addictions Research Institute, 938 West 28th Ave, Vancouver, BC V5Z 4H4, Canada; Department of Psychiatry, University of British Columbia, 2255 Wesbrook Mall, Vancouver, BC V6T 2A1, Canada
| | - Gorazd Rosoklija
- Department of Psychiatry, Columbia University, 1051 Riverside Drive, New York, NY 10032, USA
| | - J John Mann
- Department of Psychiatry, Columbia University, 1051 Riverside Drive, New York, NY 10032, USA
| | - Andrew J Dwork
- Department of Psychiatry, Columbia University, 1051 Riverside Drive, New York, NY 10032, USA
| | - Annie Moradian
- Department of Medical Genetics, University of British Columbia, C234-4500 Oak St., Vancouver, BC V6H 3B1, Canada
| | - Gregg B Morin
- Department of Medical Genetics, University of British Columbia, C234-4500 Oak St., Vancouver, BC V6H 3B1, Canada
| | - William G Honer
- BC Mental Health and Addictions Research Institute, 938 West 28th Ave, Vancouver, BC V5Z 4H4, Canada; Department of Psychiatry, University of British Columbia, 2255 Wesbrook Mall, Vancouver, BC V6T 2A1, Canada.
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21
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Cijsouw T, Ramsey AM, Lam TT, Carbone BE, Blanpied TA, Biederer T. Mapping the Proteome of the Synaptic Cleft through Proximity Labeling Reveals New Cleft Proteins. Proteomes 2018; 6:proteomes6040048. [PMID: 30487426 PMCID: PMC6313906 DOI: 10.3390/proteomes6040048] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 11/15/2018] [Accepted: 11/18/2018] [Indexed: 12/21/2022] Open
Abstract
Synapses are specialized neuronal cell-cell contacts that underlie network communication in the mammalian brain. Across neuronal populations and circuits, a diverse set of synapses is utilized, and they differ in their molecular composition to enable heterogenous connectivity patterns and functions. In addition to pre- and post-synaptic specializations, the synaptic cleft is now understood to be an integral compartment of synapses that contributes to their structural and functional organization. Aiming to map the cleft proteome, this study applied a peroxidase-mediated proximity labeling approach and used the excitatory synaptic cell adhesion protein SynCAM 1 fused to horseradish peroxidase (HRP) as a reporter in cultured cortical neurons. This reporter marked excitatory synapses as measured by confocal microcopy and was targeted to the edge zone of the synaptic cleft as determined using 3D dSTORM super-resolution imaging. Proximity labeling with a membrane-impermeant biotin-phenol compound restricted labeling to the cell surface, and Label-Free Quantitation (LFQ) mass spectrometry combined with ratiometric HRP tagging of membrane vs. synaptic surface proteins was used to identify the proteomic content of excitatory clefts. Novel cleft candidates were identified, and Receptor-type tyrosine-protein phosphatase zeta was selected and successfully validated. This study supports the robust applicability of peroxidase-mediated proximity labeling for synaptic cleft proteomics and its potential for understanding synapse heterogeneity in health and changes in diseases such as psychiatric disorders and addiction.
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Affiliation(s)
- Tony Cijsouw
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA 02111, USA.
| | - Austin M Ramsey
- Department of Physiology and Program in Neuroscience, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
| | - TuKiet T Lam
- Yale/NIDA Neuroproteomics Center, New Haven, CT 06511, USA.
- W.M. Keck Biotechnology Resource Laboratory, Yale University School of Medicine, 300 George Street, New Haven, CT 06511, USA.
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06520, USA.
| | - Beatrice E Carbone
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA 02111, USA.
| | - Thomas A Blanpied
- Department of Physiology and Program in Neuroscience, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
| | - Thomas Biederer
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA 02111, USA.
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22
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A simplified protocol for differentiation of electrophysiologically mature neuronal networks from human induced pluripotent stem cells. Mol Psychiatry 2018; 23:1336-1344. [PMID: 28416807 PMCID: PMC5984104 DOI: 10.1038/mp.2017.56] [Citation(s) in RCA: 137] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 12/24/2016] [Accepted: 02/10/2017] [Indexed: 02/07/2023]
Abstract
Progress in elucidating the molecular and cellular pathophysiology of neuropsychiatric disorders has been hindered by the limited availability of living human brain tissue. The emergence of induced pluripotent stem cells (iPSCs) has offered a unique alternative strategy using patient-derived functional neuronal networks. However, methods for reliably generating iPSC-derived neurons with mature electrophysiological characteristics have been difficult to develop. Here, we report a simplified differentiation protocol that yields electrophysiologically mature iPSC-derived cortical lineage neuronal networks without the need for astrocyte co-culture or specialized media. This protocol generates a consistent 60:40 ratio of neurons and astrocytes that arise from a common forebrain neural progenitor. Whole-cell patch-clamp recordings of 114 neurons derived from three independent iPSC lines confirmed their electrophysiological maturity, including resting membrane potential (-58.2±1.0 mV), capacitance (49.1±2.9 pF), action potential (AP) threshold (-50.9±0.5 mV) and AP amplitude (66.5±1.3 mV). Nearly 100% of neurons were capable of firing APs, of which 79% had sustained trains of mature APs with minimal accommodation (peak AP frequency: 11.9±0.5 Hz) and 74% exhibited spontaneous synaptic activity (amplitude, 16.03±0.82 pA; frequency, 1.09±0.17 Hz). We expect this protocol to be of broad applicability for implementing iPSC-based neuronal network models of neuropsychiatric disorders.
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23
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Pirazzini M, Azarnia Tehran D, Zanetti G, Rossetto O, Montecucco C. Hsp90 and Thioredoxin-Thioredoxin Reductase enable the catalytic activity of Clostridial neurotoxins inside nerve terminals. Toxicon 2017; 147:32-37. [PMID: 29111118 DOI: 10.1016/j.toxicon.2017.10.028] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 10/21/2017] [Accepted: 10/23/2017] [Indexed: 12/12/2022]
Abstract
Botulinum (BoNTs) and tetanus (TeNT) neurotoxins are the most toxic substances known and form the growing family of Clostridial neurotoxins (CNT), the etiologic agents of botulism and tetanus. CNT are composed of a metalloprotease light chain (L), linked via a disulfide bond to a heavy chain (H). H mediates the binding to nerve terminals and the membrane translocation of L into the cytosol, where its substrates, the three SNARE proteins, are localized. L translocation is accompanied by unfolding and, once delivered on the cytosolic side of the endosome membrane, it has to be reduced and reacquire the native fold to be active. The Thioredoxin-Thioredoxin Reductase system (Trx-TrxR) specifically reduces the interchain disulfide bond while the cytosolic chaperone protein Hsp90 mediates L refolding. Both steps are essential for CNT activity and their inhibition efficiently blocks the neurotoxicity in cultured neurons and mice. Trx and its reductase physically interact with Hsp90 and are loosely bound to the cytosolic side of synaptic vesicles, the organelle exploited by CNT to enter nerve terminals and wherefrom L is translocated into the cytosol. Therefore, Trx, TrxR and Hsp90 orchestrate a chaperone-redox molecular machinery that enables the catalytic activity of the L inside nerve terminals. Given the fundamental role of L reduction and refolding, this machinery represents a rational target for the development of mechanism-based antitoxins.
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Affiliation(s)
- Marco Pirazzini
- Dipartimento di Scienze Biomediche, Università di Padova, Via U. Bassi 58/B, 35121 Padova, Italy.
| | - Domenico Azarnia Tehran
- Dipartimento di Scienze Biomediche, Università di Padova, Via U. Bassi 58/B, 35121 Padova, Italy
| | - Giulia Zanetti
- Dipartimento di Scienze Biomediche, Università di Padova, Via U. Bassi 58/B, 35121 Padova, Italy
| | - Ornella Rossetto
- Dipartimento di Scienze Biomediche, Università di Padova, Via U. Bassi 58/B, 35121 Padova, Italy
| | - Cesare Montecucco
- Dipartimento di Scienze Biomediche, Università di Padova, Via U. Bassi 58/B, 35121 Padova, Italy; Istituto CNR di Neuroscienze, Università di Padova, Via U. Bassi 58/B, 35121 Padova, Italy
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24
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Wang SSH, Held RG, Wong MY, Liu C, Karakhanyan A, Kaeser PS. Fusion Competent Synaptic Vesicles Persist upon Active Zone Disruption and Loss of Vesicle Docking. Neuron 2017; 91:777-791. [PMID: 27537483 DOI: 10.1016/j.neuron.2016.07.005] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 05/23/2016] [Accepted: 06/23/2016] [Indexed: 11/19/2022]
Abstract
In a nerve terminal, synaptic vesicle docking and release are restricted to an active zone. The active zone is a protein scaffold that is attached to the presynaptic plasma membrane and opposed to postsynaptic receptors. Here, we generated conditional knockout mice removing the active zone proteins RIM and ELKS, which additionally led to loss of Munc13, Bassoon, Piccolo, and RIM-BP, indicating disassembly of the active zone. We observed a near-complete lack of synaptic vesicle docking and a strong reduction in vesicular release probability and the speed of exocytosis, but total vesicle numbers, SNARE protein levels, and postsynaptic densities remained unaffected. Despite loss of the priming proteins Munc13 and RIM and of docked vesicles, a pool of releasable vesicles remained. Thus, the active zone is necessary for synaptic vesicle docking and to enhance release probability, but releasable vesicles can be localized distant from the presynaptic plasma membrane.
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Affiliation(s)
- Shan Shan H Wang
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Richard G Held
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Man Yan Wong
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Changliang Liu
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Aziz Karakhanyan
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Pascal S Kaeser
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA.
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25
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Alfieri A, Sorokina O, Adrait A, Angelini C, Russo I, Morellato A, Matteoli M, Menna E, Boeri Erba E, McLean C, Armstrong JD, Ala U, Buxbaum JD, Brusco A, Couté Y, De Rubeis S, Turco E, Defilippi P. Synaptic Interactome Mining Reveals p140Cap as a New Hub for PSD Proteins Involved in Psychiatric and Neurological Disorders. Front Mol Neurosci 2017; 10:212. [PMID: 28713243 PMCID: PMC5492163 DOI: 10.3389/fnmol.2017.00212] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 06/15/2017] [Indexed: 01/21/2023] Open
Abstract
Altered synaptic function has been associated with neurological and psychiatric conditions including intellectual disability, schizophrenia and autism spectrum disorder (ASD). Amongst the recently discovered synaptic proteins is p140Cap, an adaptor that localizes at dendritic spines and regulates their maturation and physiology. We recently showed that p140Cap knockout mice have cognitive deficits, impaired long-term potentiation (LTP) and long-term depression (LTD), and immature, filopodia-like dendritic spines. Only a few p140Cap interacting proteins have been identified in the brain and the molecular complexes and pathways underlying p140Cap synaptic function are largely unknown. Here, we isolated and characterized the p140Cap synaptic interactome by co-immunoprecipitation from crude mouse synaptosomes, followed by mass spectrometry-based proteomics. We identified 351 p140Cap interactors and found that they cluster to sub complexes mostly located in the postsynaptic density (PSD). p140Cap interactors converge on key synaptic processes, including transmission across chemical synapses, actin cytoskeleton remodeling and cell-cell junction organization. Gene co-expression data further support convergent functions: the p140Cap interactors are tightly co-expressed with each other and with p140Cap. Importantly, the p140Cap interactome and its co-expression network show strong enrichment in genes associated with schizophrenia, autism, bipolar disorder, intellectual disability and epilepsy, supporting synaptic dysfunction as a shared biological feature in brain diseases. Overall, our data provide novel insights into the molecular organization of the synapse and indicate that p140Cap acts as a hub for postsynaptic complexes relevant to psychiatric and neurological disorders.
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Affiliation(s)
- Annalisa Alfieri
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, Università di TorinoTorino, Italy
| | - Oksana Sorokina
- The Institute for Adaptive and Neural Computation, School of Informatics, University of EdinburghEdinburgh, United Kingdom
| | - Annie Adrait
- Université Grenoble Alpes, iRTSV-BGEGrenoble, France.,CEA, iRTSV-BGEGrenoble, France.,Institut National de la Santé et de la Recherche Médicale, BGEGrenoble, France
| | - Costanza Angelini
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, Università di TorinoTorino, Italy
| | - Isabella Russo
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, Università di TorinoTorino, Italy
| | - Alessandro Morellato
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, Università di TorinoTorino, Italy
| | - Michela Matteoli
- Institute of Neuroscience, Consiglio Nazionale delle Ricerche (CNR)Milan, Italy.,Humanitas Clinical and Research Center, IRCCSRozzano, Italy
| | - Elisabetta Menna
- Institute of Neuroscience, Consiglio Nazionale delle Ricerche (CNR)Milan, Italy.,Humanitas Clinical and Research Center, IRCCSRozzano, Italy
| | - Elisabetta Boeri Erba
- Institut de Biologie Structurale, Université Grenoble AlpesGrenoble, France.,CEA, DSV, IBSGrenoble, France.,Centre National de la Recherche Scientifique, IBSGrenoble, France
| | - Colin McLean
- The Institute for Adaptive and Neural Computation, School of Informatics, University of EdinburghEdinburgh, United Kingdom
| | - J Douglas Armstrong
- The Institute for Adaptive and Neural Computation, School of Informatics, University of EdinburghEdinburgh, United Kingdom
| | - Ugo Ala
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, Università di TorinoTorino, Italy.,GenoBiToUS-Genomics and Bioinformatics, Università di TorinoTurin, Italy
| | - Joseph D Buxbaum
- Seaver Autism Center for Research and Treatment, Department of Psychiatry, Icahn School of Medicine at Mount SinaiNew York, NY, United States.,Department of Psychiatry, Icahn School of Medicine at Mount SinaiNew York, NY, United States.,Department of Neuroscience, Icahn School of Medicine at Mount SinaiNew York, NY, United States.,Friedman Brain Institute, Icahn School of Medicine at Mount SinaiNew York, NY, United States.,Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount SinaiNew York, NY, United States.,Mindich Child Health and Development Institute, Icahn School of Medicine at Mount SinaiNew York, NY, United States
| | - Alfredo Brusco
- Department of Medical Sciences, Università di TorinoTurin, Italy.,Medical Genetics Unit, Azienda Ospedaliera Città della Salute e della Scienza di TorinoTurin, Italy
| | - Yohann Couté
- Université Grenoble Alpes, iRTSV-BGEGrenoble, France.,CEA, iRTSV-BGEGrenoble, France.,Institut National de la Santé et de la Recherche Médicale, BGEGrenoble, France
| | - Silvia De Rubeis
- Seaver Autism Center for Research and Treatment, Department of Psychiatry, Icahn School of Medicine at Mount SinaiNew York, NY, United States.,Department of Psychiatry, Icahn School of Medicine at Mount SinaiNew York, NY, United States
| | - Emilia Turco
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, Università di TorinoTorino, Italy
| | - Paola Defilippi
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, Università di TorinoTorino, Italy
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26
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Azarnia Tehran D, Pirazzini M, Leka O, Mattarei A, Lista F, Binz T, Rossetto O, Montecucco C. Hsp90 is involved in the entry of clostridial neurotoxins into the cytosol of nerve terminals. Cell Microbiol 2016; 19. [DOI: 10.1111/cmi.12647] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Revised: 07/06/2016] [Accepted: 07/08/2016] [Indexed: 12/31/2022]
Affiliation(s)
- Domenico Azarnia Tehran
- Department of Biomedical Sciences; University of Padova; Via Ugo Bassi 58/B 35121 Padova Italy
| | - Marco Pirazzini
- Department of Biomedical Sciences; University of Padova; Via Ugo Bassi 58/B 35121 Padova Italy
| | - Oneda Leka
- Department of Biomedical Sciences; University of Padova; Via Ugo Bassi 58/B 35121 Padova Italy
| | - Andrea Mattarei
- Department of Chemical Sciences; University of Padova; Via F. Marzolo 1 35131 Padova Italy
| | - Florigio Lista
- Histology and Molecular Biology Section; Army Medical and Veterinary Research Center; Via Santo Stefano Rotondo 4 00184 Rome Italy
| | - Thomas Binz
- Medizinische Hochschule Hannover; Institut für Physiologische Chemie OE4310; 30625 Hannover Germany
| | - Ornella Rossetto
- Department of Biomedical Sciences; University of Padova; Via Ugo Bassi 58/B 35121 Padova Italy
| | - Cesare Montecucco
- Department of Biomedical Sciences; University of Padova; Via Ugo Bassi 58/B 35121 Padova Italy
- National Research Institute of Neuroscience; University of Padova; Via Ugo Bassi 58/B 35121 Padova Italy
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27
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Bodaleo FJ, Gonzalez-Billault C. The Presynaptic Microtubule Cytoskeleton in Physiological and Pathological Conditions: Lessons from Drosophila Fragile X Syndrome and Hereditary Spastic Paraplegias. Front Mol Neurosci 2016; 9:60. [PMID: 27504085 PMCID: PMC4958632 DOI: 10.3389/fnmol.2016.00060] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 07/11/2016] [Indexed: 11/21/2022] Open
Abstract
The capacity of the nervous system to generate neuronal networks relies on the establishment and maintenance of synaptic contacts. Synapses are composed of functionally different presynaptic and postsynaptic compartments. An appropriate synaptic architecture is required to provide the structural basis that supports synaptic transmission, a process involving changes in cytoskeletal dynamics. Actin microfilaments are the main cytoskeletal components present at both presynaptic and postsynaptic terminals in glutamatergic synapses. However, in the last few years it has been demonstrated that microtubules (MTs) transiently invade dendritic spines, promoting their maturation. Nevertheless, the presence and functions of MTs at the presynaptic site are still a matter of debate. Early electron microscopy (EM) studies revealed that MTs are present in the presynaptic terminals of the central nervous system (CNS) where they interact with synaptic vesicles (SVs) and reach the active zone. These observations have been reproduced by several EM protocols; however, there is empirical heterogeneity in detecting presynaptic MTs, since they appear to be both labile and unstable. Moreover, increasing evidence derived from studies in the fruit fly neuromuscular junction proposes different roles for MTs in regulating presynaptic function in physiological and pathological conditions. In this review, we summarize the main findings that support the presence and roles of MTs at presynaptic terminals, integrating descriptive and biochemical analyses, and studies performed in invertebrate genetic models.
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Affiliation(s)
- Felipe J Bodaleo
- Laboratory of Cell and Neuronal Dynamics, Department of Biology, Faculty of Sciences, Universidad de ChileSantiago, Chile; Center for Geroscience, Brain Health and Metabolism (GERO)Santiago, Chile
| | - Christian Gonzalez-Billault
- Laboratory of Cell and Neuronal Dynamics, Department of Biology, Faculty of Sciences, Universidad de ChileSantiago, Chile; Center for Geroscience, Brain Health and Metabolism (GERO)Santiago, Chile; The Buck Institute for Research on Aging, NovatoCA, USA
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28
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Pers TH, Timshel P, Ripke S, Lent S, Sullivan PF, O'Donovan MC, Franke L, Hirschhorn JN. Comprehensive analysis of schizophrenia-associated loci highlights ion channel pathways and biologically plausible candidate causal genes. Hum Mol Genet 2016; 25:1247-54. [PMID: 26755824 PMCID: PMC4764200 DOI: 10.1093/hmg/ddw007] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Revised: 12/29/2015] [Accepted: 01/05/2015] [Indexed: 12/26/2022] Open
Abstract
Over 100 associated genetic loci have been robustly associated with schizophrenia. Gene prioritization and pathway analysis have focused on a priori hypotheses and thus may have been unduly influenced by prior assumptions and missed important causal genes and pathways. Using a data-driven approach, we show that genes in associated loci: (1) are highly expressed in cortical brain areas; (2) are enriched for ion channel pathways (false discovery rates <0.05); and (3) contain 62 genes that are functionally related to each other and hence represent promising candidates for experimental follow up. We validate the relevance of the prioritized genes by showing that they are enriched for rare disruptive variants and de novo variants from schizophrenia sequencing studies (odds ratio 1.67, P = 0.039), and are enriched for genes encoding members of mouse and human postsynaptic density proteomes (odds ratio 4.56, P = 5.00 × 10(-4); odds ratio 2.60, P = 0.049).The authors wish it to be known that, in their opinion, the first 2 authors should be regarded as joint First Author.
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Affiliation(s)
- Tune H Pers
- Division of Endocrinology and Center for Basic and Translational Obesity Research, Boston Children's Hospital, Boston, MA 02115, USA, Medical and Population Genetics Program and The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 1, København Ø 2100, Denmark, Department of Epidemiology Research, Statens Serum Institut, 2300 Copenhagen, Denmark
| | - Pascal Timshel
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 1, København Ø 2100, Denmark, Department of Epidemiology Research, Statens Serum Institut, 2300 Copenhagen, Denmark
| | - Stephan Ripke
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA, Analytical and Translational Genetics Unit, Massachusetts General Hospital, Boston, MA 02142, USA
| | | | - Patrick F Sullivan
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm SE-17177, Sweden, Department of Genetics, University of North Carolina, Chapel Hill, NC 27599-7264, USA, Department of Psychiatry, University of North Carolina, Chapel Hill, NC 27599-7160, USA
| | - Michael C O'Donovan
- MRC Centre for Neuropsychiatric Genetics and Genomics, Institute of Psychological Medicine and Clinical Neurosciences, School of Medicine and National Centre for Mental Health, Cardiff University, Cardiff CF24 4HQ, UK
| | - Lude Franke
- Department of Genetics, University of Groningen, University Medical Centre Groningen, Groningen 9711, The Netherlands and
| | - Joel N Hirschhorn
- Division of Endocrinology and Center for Basic and Translational Obesity Research, Boston Children's Hospital, Boston, MA 02115, USA, Medical and Population Genetics Program and Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
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Yagensky O, Kalantary Dehaghi T, Chua JJE. The Roles of Microtubule-Based Transport at Presynaptic Nerve Terminals. Front Synaptic Neurosci 2016; 8:3. [PMID: 26903856 PMCID: PMC4748046 DOI: 10.3389/fnsyn.2016.00003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 01/29/2016] [Indexed: 01/19/2023] Open
Abstract
Targeted intracellular movement of presynaptic proteins plays important roles during synapse formation and, later, in the homeostatic maintenance of mature synapses. Movement of these proteins, often as vesicular packages, is mediated by motor complexes travelling along intracellular cytoskeletal networks. Presynaptic protein transport by kinesin motors in particular plays important roles during synaptogenesis to bring newly synthesized proteins to establish nascent synaptic sites. Conversely, movement of proteins away from presynaptic sites by Dynein motors enables synapse-nuclear signaling and allows for synaptic renewal through degradation of unwanted or damaged proteins. Remarkably, recent data has indicated that synaptic and protein trafficking machineries can modulate each other's functions. Here, we survey the mechanisms involved in moving presynaptic components to and away from synapses and how this process supports presynaptic function.
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Affiliation(s)
- Oleksandr Yagensky
- Research Group Protein Trafficking in Synaptic Development and Function, Department of Neurobiology, Max-Planck-Institute for Biophysical Chemistry Göttingen, Germany
| | - Tahere Kalantary Dehaghi
- Research Group Protein Trafficking in Synaptic Development and Function, Department of Neurobiology, Max-Planck-Institute for Biophysical Chemistry Göttingen, Germany
| | - John Jia En Chua
- Research Group Protein Trafficking in Synaptic Development and Function, Department of Neurobiology, Max-Planck-Institute for Biophysical ChemistryGöttingen, Germany; Interactomics and Intracellular Trafficking Laboratory, Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, SingaporeSingapore; Neurobiology/Ageing Programme, National University of Singapore, SingaporeSingapore
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Zhou J, Liu Z, Yu J, Han X, Fan S, Shao W, Chen J, Qiao R, Xie P. Quantitative Proteomic Analysis Reveals Molecular Adaptations in the Hippocampal Synaptic Active Zone of Chronic Mild Stress-Unsusceptible Rats. Int J Neuropsychopharmacol 2015; 19:pyv100. [PMID: 26364272 PMCID: PMC4772275 DOI: 10.1093/ijnp/pyv100] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 08/31/2015] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND While stressful events are recognized as an important cause of major depressive disorder, some individuals exposed to life stressors maintain normal psychological functioning. The molecular mechanism(s) underlying this phenomenon remain unclear. Abnormal transmission and plasticity of hippocampal synapses have been implied to play a key role in the pathoetiology of major depressive disorder. METHODS A chronic mild stress protocol was applied to separate susceptible and unsusceptible rat subpopulations. Proteomic analysis using an isobaric tag for relative and absolute quantitation coupled with tandem mass spectrometry was performed to identify differential proteins in enriched hippocampal synaptic junction preparations. RESULTS A total of 4318 proteins were quantified, and 89 membrane proteins were present in differential amounts. Of these, SynaptomeDB identified 81 (91%) having a synapse-specific localization. The unbiased profiles identified several candidate proteins within the synaptic junction that may be associated with stress vulnerability or insusceptibility. Subsequent functional categorization revealed that protein systems particularly involved in membrane trafficking at the synaptic active zone exhibited a positive strain as potential molecular adaptations in the unsusceptible rats. Moreover, through STRING and immunoblotting analysis, membrane-associated GTP-bound Rab3a and Munc18-1 appear to coregulate syntaxin-1/SNAP25/VAMP2 assembly at the hippocampal presynaptic active zone of unsusceptible rats, facilitating SNARE-mediated membrane fusion and neurotransmitter release, and may be part of a stress-protection mechanism in actively maintaining an emotional homeostasis. CONCLUSIONS The present results support the concept that there is a range of potential protein adaptations in the hippocampal synaptic active zone of unsusceptible rats, revealing new investigative targets that may contribute to a better understanding of stress insusceptibility.
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Affiliation(s)
- Jian Zhou
- Institute of Neuroscience and the Collaborative Innovation Center for Brain Science, Chongqing Medical University, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Chongqing Key Laboratory of Neurobiology, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China (Drs Liu, Han, Fan, Shao, and Xie)
| | - Zhao Liu
- Institute of Neuroscience and the Collaborative Innovation Center for Brain Science, Chongqing Medical University, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Chongqing Key Laboratory of Neurobiology, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China (Drs Liu, Han, Fan, Shao, and Xie)
| | - Jia Yu
- Institute of Neuroscience and the Collaborative Innovation Center for Brain Science, Chongqing Medical University, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Chongqing Key Laboratory of Neurobiology, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China (Drs Liu, Han, Fan, Shao, and Xie)
| | - Xin Han
- Institute of Neuroscience and the Collaborative Innovation Center for Brain Science, Chongqing Medical University, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Chongqing Key Laboratory of Neurobiology, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China (Drs Liu, Han, Fan, Shao, and Xie)
| | - Songhua Fan
- Institute of Neuroscience and the Collaborative Innovation Center for Brain Science, Chongqing Medical University, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Chongqing Key Laboratory of Neurobiology, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China (Drs Liu, Han, Fan, Shao, and Xie)
| | - Weihua Shao
- Institute of Neuroscience and the Collaborative Innovation Center for Brain Science, Chongqing Medical University, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Chongqing Key Laboratory of Neurobiology, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China (Drs Liu, Han, Fan, Shao, and Xie)
| | - Jianjun Chen
- Institute of Neuroscience and the Collaborative Innovation Center for Brain Science, Chongqing Medical University, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Chongqing Key Laboratory of Neurobiology, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China (Drs Liu, Han, Fan, Shao, and Xie)
| | - Rui Qiao
- Institute of Neuroscience and the Collaborative Innovation Center for Brain Science, Chongqing Medical University, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Chongqing Key Laboratory of Neurobiology, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China (Drs Liu, Han, Fan, Shao, and Xie)
| | - Peng Xie
- Institute of Neuroscience and the Collaborative Innovation Center for Brain Science, Chongqing Medical University, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Chongqing Key Laboratory of Neurobiology, Chongqing, China (Drs Zhou, Liu, Yu, Han, Fan, Shao, Chen, Qiao, and Xie); Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China (Drs Liu, Han, Fan, Shao, and Xie).
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Pirazzini M, Azarnia Tehran D, Zanetti G, Lista F, Binz T, Shone CC, Rossetto O, Montecucco C. The thioredoxin reductase--Thioredoxin redox system cleaves the interchain disulphide bond of botulinum neurotoxins on the cytosolic surface of synaptic vesicles. Toxicon 2015; 107:32-6. [PMID: 26130523 DOI: 10.1016/j.toxicon.2015.06.019] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 06/23/2015] [Indexed: 11/16/2022]
Abstract
Botulinum neurotoxins (BoNTs) are Janus toxins, as they are at the same time the most deadly substances known and one of the safest drugs used in human therapy. They specifically block neurotransmission at peripheral nerves through the proteolysis of SNARE proteins, i.e. the essential proteins which are the core of the neuroexocytosis machinery. Even if BoNTs are traditionally known as seven main serotypes, their actual number is much higher as each serotype exists in many different subtypes, with individual biological properties and little antigenic relations. Since BoNTs can be used as biological weapons, and the only currently available therapy is based on immunological approaches, the existence of so many different subtypes is a major safety problem. Nevertheless, all BoNT isoforms are structurally similar and intoxicate peripheral nerve endings via a conserved mechanism. They consist of two chains linked by a unique disulphide bond which must be reduced to enable their toxicity. We found that thioredoxin 1 and its reductase compose the cell redox system responsible for this reduction, and its inhibition via specific chemicals significantly reduces BoNTs activity, in vitro as well as in vivo. Such molecules can be considered as lead compounds for the development of pan-inhibitors.
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Affiliation(s)
- Marco Pirazzini
- Dipartimento di Scienze Biomediche, Università di Padova, Via U. Bassi 58/B, 35121 Padova, Italy.
| | - Domenico Azarnia Tehran
- Dipartimento di Scienze Biomediche, Università di Padova, Via U. Bassi 58/B, 35121 Padova, Italy
| | - Giulia Zanetti
- Dipartimento di Scienze Biomediche, Università di Padova, Via U. Bassi 58/B, 35121 Padova, Italy
| | - Florigio Lista
- Histology and Molecular Biology Section, Army Medical and Veterinary Research Center, Via Santo Stefano Rotondo 4, 00184 Rome, Italy
| | - Thomas Binz
- Institut fur Biochemie, Medizinische Hochschule Hannover, 30623 Hannover, Germany
| | - Clifford C Shone
- Public Health England, Porton Down, Salisbury, Wiltshire, SP4 OJG, UK
| | - Ornella Rossetto
- Dipartimento di Scienze Biomediche, Università di Padova, Via U. Bassi 58/B, 35121 Padova, Italy
| | - Cesare Montecucco
- Dipartimento di Scienze Biomediche, Università di Padova, Via U. Bassi 58/B, 35121 Padova, Italy; Istituto CNR di Neuroscienze, Università di Padova, Via U. Bassi 58/B, 35121 Padova, Italy
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Regional Specializations of the PAZ Proteomes Derived from Mouse Hippocampus, Olfactory Bulb and Cerebellum. Proteomes 2015; 3:74-88. [PMID: 28248263 PMCID: PMC5217373 DOI: 10.3390/proteomes3020074] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Accepted: 05/05/2015] [Indexed: 11/25/2022] Open
Abstract
Neurotransmitter release as well as structural and functional dynamics at the presynaptic active zone (PAZ) comprising synaptic vesicles attached to the presynaptic plasma membrane are mediated and controlled by its proteinaceous components. Here we describe a novel experimental design to immunopurify the native PAZ-complex from individual mouse brain regions such as olfactory bulb, hippocampus, and cerebellum with high purity that is essential for comparing their proteome composition. Interestingly, quantitative immunodetection demonstrates significant differences in the abundance of prominent calcium-dependent PAZ constituents. Furthermore, we characterized the proteomes of the immunoisolated PAZ derived from the three brain regions by mass spectrometry. The proteomes of the release sites from the respective regions exhibited remarkable differences in the abundance of a large variety of PAZ constituents involved in various functional aspects of the release sites such as calcium homeostasis, synaptic plasticity and neurogenesis. On the one hand, our data support an identical core architecture of the PAZ for all brain regions and, on the other hand, demonstrate that the proteinaceous composition of their presynaptic active zones vary, suggesting that changes in abundance of individual proteins strengthen the ability of the release sites to adapt to specific functional requirements.
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Michel K, Müller JA, Oprişoreanu AM, Schoch S. The presynaptic active zone: A dynamic scaffold that regulates synaptic efficacy. Exp Cell Res 2015; 335:157-64. [PMID: 25720549 DOI: 10.1016/j.yexcr.2015.02.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2015] [Accepted: 02/10/2015] [Indexed: 12/30/2022]
Abstract
Before fusing with the presynaptic plasma membrane to release neurotransmitter into the synaptic cleft synaptic vesicles have to be recruited to and docked at a specialized area of the presynaptic nerve terminal, the active zone. Exocytosis of synaptic vesicles is restricted to the presynaptic active zone, which is characterized by a unique and highly interconnected set of proteins. The protein network at the active zone is integrally involved in this process and also mediates changes in release properties, for example in response to alterations in the level of neuronal network activity. In recent years the development of novel techniques has greatly advanced our understanding of the molecular identity of respective active zone components as well as of the ultrastructure of this membranous subcompartment and of the SV release machinery. Furthermore, active zones are now viewed as dynamic structures whose composition and size are correlated with synaptic efficacy. Therefore, the dynamic remodeling of the protein network at the active zone has emerged as one potential mechanism underlying acute and long-term synaptic plasticity. Here, we will discuss this recent progress and its implications for our view of the role of the AZ in synaptic function.
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Affiliation(s)
- Katrin Michel
- Section for Translational Epilepsy Research, Department of Neuropathology, University of Bonn Medical Center, 53105 Bonn, Germany
| | - Johannes Alexander Müller
- Section for Translational Epilepsy Research, Department of Neuropathology, University of Bonn Medical Center, 53105 Bonn, Germany
| | - Ana-Maria Oprişoreanu
- Section for Translational Epilepsy Research, Department of Neuropathology, University of Bonn Medical Center, 53105 Bonn, Germany
| | - Susanne Schoch
- Section for Translational Epilepsy Research, Department of Neuropathology, University of Bonn Medical Center, 53105 Bonn, Germany; Department of Epileptology University of Bonn Medical Center, 53105 Bonn, Germany.
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Liu L, Fujino K, Nishimura M. Pre-synaptic localization of the γ-secretase-inhibiting protein p24α2 in the mammalian brain. J Neurochem 2015; 133:422-31. [PMID: 25438880 DOI: 10.1111/jnc.13000] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Revised: 11/19/2014] [Accepted: 11/22/2014] [Indexed: 12/13/2022]
Abstract
Dysregulated metabolism and consequent extracellular accumulation of amyloid-β (Aβ) peptides in the brain underlie the pathogenesis of Alzheimer's disease. Extracellular Aβ in the brain parenchyma is mainly secreted from the pre-synaptic terminals of neuronal cells in a synaptic activity-dependent manner. The p24 family member p24α2 reportedly attenuates Aβ generation by inhibiting γ-secretase processing of amyloid precursor protein; however, the pattern of expression and localization of p24α2 in the brain remains unknown. We performed immunohistochemical staining and subcellular fractionation for p24α2 in the mouse brain. Immunostaining showed that p24α2 is broadly distributed in the gray matter of the central nervous system and is predominantly localized to synapses. Subcellular fractionation revealed prominent localization of p24α2 in the pre-synaptic terminals. Immunoisolation of synaptic vesicles (SV) indicated that p24α2 is condensed at active zone-docked SV. During development, p24α2 expression is highest in the post-natal period and gradually decreases with age. We also confirmed that amyloid precursor protein and γ-secretase components are localized at active zone-docked SV. Our results suggest a novel functional role for p24α2 in the regulation of synaptic transmission and synaptogenesis, and provide evidence for the participation of p24α2 in the regulation of Aβ generation and secretion in the brain. The p24 family member p24α2 attenuates amyloid-β (Aβ) generation by inhibiting the γ-secretase processing. We report that p24α2 is condensed at active zone-docked synaptic vesicles in the brain. p24α2 expression is highest in the post-natal period and gradually decreases with age. Our results suggest a novel function for p24α2 at the synapse, including the regulation of brain Aβ generation.
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Affiliation(s)
- Lei Liu
- Molecular Neuroscience Research Center, Shiga University of Medical Science, Shiga, Japan
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35
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Pocklington AJ, O'Donovan M, Owen MJ. The synapse in schizophrenia. Eur J Neurosci 2014; 39:1059-67. [PMID: 24712986 DOI: 10.1111/ejn.12489] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2013] [Revised: 12/19/2013] [Accepted: 12/20/2013] [Indexed: 02/06/2023]
Abstract
It has been several decades since synaptic dysfunction was first suggested to play a role in schizophrenia, but only in the last few years has convincing evidence been obtained as progress has been made in elucidating the genetic underpinnings of the disorder. In the intervening years much has been learned concerning the complex macromolecular structure of the synapse itself, and genetic studies are now beginning to draw upon these advances. Here we outline our current understanding of the genetic architecture of schizophrenia and examine the evidence for synaptic involvement. A strong case can now be made that disruption of glutamatergic signalling pathways regulating synaptic plasticity contributes to the aetiology of schizophrenia.
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Affiliation(s)
- Andrew J Pocklington
- MRC Centre for Neuropsychiatric Genetics and Genomics, Institute of Psychological Medicine and Clinical Neurosciences, Cardiff University School of Medicine, Hadyn Ellis Building, Maindy Road, Cathays, Cardiff, CF24 4HQ, UK
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Ttyh1 protein is expressed in glia in vitro and shows elevated expression in activated astrocytes following status epilepticus. Neurochem Res 2014; 39:2516-26. [PMID: 25316497 PMCID: PMC4246129 DOI: 10.1007/s11064-014-1455-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Revised: 09/26/2014] [Accepted: 10/08/2014] [Indexed: 11/29/2022]
Abstract
In a previous study, we showed that Ttyh1 protein is expressed in neurons in vitro and in vivo in the form of punctuate structures, which are localized to neuropil and neuronal somata. Herein, we provide the first description of Ttyh1 protein expression in astrocytes, oligodendrocytes and microglia in vitro. Moreover, using double immunofluorescence, we show Ttyh1 protein expression in activated astrocytes in the hippocampus following amygdala stimulation-induced status epilepticus. We demonstrate that in migrating astrocytes in in vitro wound model Ttyh1 concentrates at the edges of extending processes. These data suggest that Ttyh1 not only participates in shaping neuronal morphology, as previously described, but may also play a role in the function of activated glia in brain pathology. To localize Ttyh1 expression in the cellular compartments of neurons and astrocytes, we performed in vitro double immunofluorescent staining using markers for the following subcellular structures: endoplasmic reticulum (GRP78), Golgi apparatus (GM130), clathrin-coated vehicles (clathrin), early endosomes (Rab5 and APPL2), recycling endosomes (Rab11), trans-Golgi network (TGN46), endoplasmic reticulum membrane (calnexin), late endosomes and lysosomes (LAMP1) and synaptic vesicles (synaptoporin and synaptotagmin 1). We found that Ttyh1 is present in the endoplasmic reticulum, Golgi apparatus and clathrin-coated vesicles (clathrin) in both neurons and astrocytes and also in late endosomes or lysosomes in astrocytes. The presence of Ttyh1 was negligible in early endosomes, recycling endosomes, trans-Golgi network, endoplasmic reticulum membrane and synaptic vesicles.
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37
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Chua JJE. Macromolecular complexes at active zones: integrated nano-machineries for neurotransmitter release. Cell Mol Life Sci 2014; 71:3903-16. [PMID: 24912984 PMCID: PMC11113288 DOI: 10.1007/s00018-014-1657-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 05/22/2014] [Accepted: 05/23/2014] [Indexed: 02/06/2023]
Abstract
The release of neurotransmitters from synaptic vesicles exocytosing at presynaptic nerve terminals is a critical event in the initiation of synaptic transmission. This event occurs at specialized sites known as active zones. The task of faithfully executing various steps in the process is undertaken by careful orchestration of overlapping sets of molecular nano-machineries upon a core macromolecular scaffold situated at active zones. However, their composition remains incompletely elucidated. This review provides an overview of the role of the active zone in mediating neurotransmitter release and summarizes the recent progress using neuroproteomic approaches to decipher their composition. Key proteins of these nano-machineries are highlighted.
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Affiliation(s)
- John Jia En Chua
- Department of Neurobiology, Max-Planck-Institute for Biophysical Chemistry, Am Fassberg 11, 37077, Göttingen, Germany,
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Moczulska KE, Pichler P, Schutzbier M, Schleiffer A, Rumpel S, Mechtler K. Deep and precise quantification of the mouse synaptosomal proteome reveals substantial remodeling during postnatal maturation. J Proteome Res 2014; 13:4310-24. [PMID: 25157418 DOI: 10.1021/pr500456t] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
During postnatal murine maturation, behavioral patterns emerge and become shaped by experience-dependent adaptations. During the same period, the morphology of dendritic spines, the morphological correlates of excitatory synapses, is known to change, and there is evidence of concurrent alterations of the synaptosomal protein machinery. To obtain comprehensive and quantitative insights in the developmental regulation of the proteome of synapses, we prepared cortical synaptosomal fractions from a total of 16 individual juvenile and adult mouse brains (age 3 or 8 weeks, respectively). We then applied peptide-based iTRAQ labeling (four pools of 4 animals) and high-resolution two-dimensional peptide fractionation (99 SCX fractions and 3 h reversed-phase gradients) using a hybrid CID-HCD acquisition method on a Velos Orbitrap mass spectrometer to identify a comprehensive set of synaptic proteins and to quantify changes in protein expression. We obtained a data set tracking expression levels of 3500 proteins mapping to 3427 NCBI GeneIDs during development with complete quantification data available for 3422 GeneIDs, which, to the best of our knowledge, constitutes the deepest coverage of the synaptosome proteome to date. The inclusion of biological replicates in a single mass spectrometry analysis demonstrated both high reproducibility of our synaptosome preparation method as well as high precision of our quantitative data (correlation coefficient R = 0.87 for the biological replicates). To evaluate the validity of our data, the developmental regulation of eight proteins identified in our analysis was confirmed independently using western blotting. A gene ontology analysis confirmed the synaptosomal nature of a large fraction of identified proteins. Of note, the set of the most strongly regulated proteins revealed candidates involved in neurological processes in health and disease states. This highlights the fact that developmentally regulated proteins can play additional roles in neurological disease processes. All data have been deposited to the ProteomeXchange with identifier PXD000552.
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Affiliation(s)
- Kaja Ewa Moczulska
- Research Institute of Molecular Pathology , Dr. Bohr-Gasse 7, 1030 Vienna, Austria
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Thioredoxin and its reductase are present on synaptic vesicles, and their inhibition prevents the paralysis induced by botulinum neurotoxins. Cell Rep 2014; 8:1870-1878. [PMID: 25220457 DOI: 10.1016/j.celrep.2014.08.017] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 07/29/2014] [Accepted: 08/07/2014] [Indexed: 11/23/2022] Open
Abstract
Botulinum neurotoxins consist of a metalloprotease linked via a conserved interchain disulfide bond to a heavy chain responsible for neurospecific binding and translocation of the enzymatic domain in the nerve terminal cytosol. The metalloprotease activity is enabled upon disulfide reduction and causes neuroparalysis by cleaving the SNARE proteins. Here, we show that the thioredoxin reductase-thioredoxin protein disulfide-reducing system is present on synaptic vesicles and that it is functional and responsible for the reduction of the interchain disulfide of botulinum neurotoxin serotypes A, C, and E. Specific inhibitors of thioredoxin reductase or thioredoxin prevent intoxication of cultured neurons in a dose-dependent manner and are also very effective inhibitors of the paralysis of the neuromuscular junction. We found that this group of inhibitors of botulinum neurotoxins is very effective in vivo. Most of them are nontoxic and are good candidates as preventive and therapeutic drugs for human botulism.
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Laßek M, Weingarten J, Volknandt W. The synaptic proteome. Cell Tissue Res 2014; 359:255-65. [PMID: 25038742 DOI: 10.1007/s00441-014-1943-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 06/04/2014] [Indexed: 11/29/2022]
Abstract
Synapses are focal hot spots for signal transduction and plasticity in the brain. A synapse comprises an axon terminus, the presynapse, the synaptic cleft containing extracellular matrix proteins as well as adhesion molecules, and the postsynaptic density as target structure for chemical signaling. The proteomes of the presynaptic and postsynaptic active zones control neurotransmitter release and perception. These tasks demand short- and long-term structural and functional dynamics of the synapse mediated by its proteinaceous inventory. This review addresses subcellular fractionation protocols and the related proteomic approaches to the various synaptic subcompartments with an emphasis on the presynaptic active zone (PAZ). Furthermore, it discusses major constituents of the PAZ including the amyloid precursor protein family members. Numerous proteins regulating the rearrangement of the cytoskeleton are indicative of the functional and structural dynamics of the pre- and postsynapse. The identification of protein candidates of the synapse provides the basis for further analyzing the interaction of synaptic proteins with their targets, and the effect of their deletion opens novel insights into the functional role of these proteins in neuronal communication. The knowledge of the molecular interactome is also a prerequisite for understanding numerous neurodegenerative diseases.
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Affiliation(s)
- Melanie Laßek
- Molecular and Cellular Neurobiology, Goethe University, Frankfurt, Germany
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41
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Zaręba-Kozioł M, Szwajda A, Dadlez M, Wysłouch-Cieszyńska A, Lalowski M. Global analysis of S-nitrosylation sites in the wild type (APP) transgenic mouse brain-clues for synaptic pathology. Mol Cell Proteomics 2014; 13:2288-305. [PMID: 24895380 DOI: 10.1074/mcp.m113.036079] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Alzheimer's disease (AD) is characterized by an early synaptic loss, which strongly correlates with the severity of dementia. The pathogenesis and causes of characteristic AD symptoms are not fully understood. Defects in various cellular cascades were suggested, including the imbalance in production of reactive oxygen and nitrogen species. Alterations in S-nitrosylation of several proteins were previously demonstrated in various AD animal models and patients. In this work, using combined biotin-switch affinity/nano-LC-MS/MS and bioinformatic approaches we profiled endogenous S-nitrosylation of brain synaptosomal proteins from wild type and transgenic mice overexpressing mutated human Amyloid Precursor Protein (hAPP). Our data suggest involvement of S-nitrosylation in the regulation of 138 synaptic proteins, including MAGUK, CamkII, or synaptotagmins. Thirty-eight proteins were differentially S-nitrosylated in hAPP mice only. Ninety-five S-nitrosylated peptides were identified for the first time (40% of total, including 33 peptides exclusively in hAPP synaptosomes). We verified differential S-nitrosylation of 10 (26% of all identified) synaptosomal proteins from hAPP mice, by Western blotting with specific antibodies. Functional enrichment analysis linked S-nitrosylated proteins to various cellular pathways, including: glycolysis, gluconeogenesis, calcium homeostasis, ion, and vesicle transport, suggesting a basic role of this post-translational modification in the regulation of synapses. The linkage of SNO-proteins to axonal guidance and other processes related to APP metabolism exclusively in the hAPP brain, implicates S-nitrosylation in the pathogenesis of Alzheimer's disease.
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Affiliation(s)
- Monika Zaręba-Kozioł
- From the ‡Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | | | - Michał Dadlez
- From the ‡Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | | | - Maciej Lalowski
- ¶Biomedicum Helsinki, Institute of Biomedicine, Biochemistry/Developmental Biology, Meilahti Clinical Proteomics Core Unit, University of Helsinki, Finland; ‖Folkhälsan Institute of Genetics, Helsinki, Finland
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Laßek M, Weingarten J, Volknandt W. The Proteome of the Murine Presynaptic Active Zone. Proteomes 2014; 2:243-257. [PMID: 28250380 PMCID: PMC5302740 DOI: 10.3390/proteomes2020243] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Revised: 04/09/2014] [Accepted: 04/21/2014] [Indexed: 01/09/2023] Open
Abstract
The proteome of the presynaptic active zone controls neurotransmitter release and the short- and long-term structural and functional dynamics of the nerve terminal. The proteinaceous inventory of the presynaptic active zone has recently been reported. This review will evaluate the subcellular fractionation protocols and the proteomic approaches employed. A breakthrough for the identification of the proteome of the presynaptic active zone was the successful employment of antibodies directed against a cytosolic epitope of membrane integral synaptic vesicle proteins for the immunopurification of synaptic vesicles docked to the presynaptic plasma membrane. Combining immunopurification and subsequent analytical mass spectrometry, hundreds of proteins, including synaptic vesicle proteins, components of the presynaptic fusion and retrieval machinery, proteins involved in intracellular and extracellular signaling and a large variety of adhesion molecules, were identified. Numerous proteins regulating the rearrangement of the cytoskeleton are indicative of the functional and structural dynamics of the presynapse. This review will critically discuss both the experimental approaches and prominent protein candidates identified. Many proteins have not previously been assigned to the presynaptic release sites and may be directly involved in the short- and long-term structural modulation of the presynaptic compartment. The identification of proteinaceous constituents of the presynaptic active zone provides the basis for further analyzing the interaction of presynaptic proteins with their targets and opens novel insights into the functional role of these proteins in neuronal communication.
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Affiliation(s)
- Melanie Laßek
- Institute for Cell Biology and Neuroscience, Department Molecular and Cellular Neurobiology, Max von Laue Str. 13, 60438 Frankfurt am Main, Germany.
| | - Jens Weingarten
- Institute for Cell Biology and Neuroscience, Department Molecular and Cellular Neurobiology, Max von Laue Str. 13, 60438 Frankfurt am Main, Germany.
| | - Walter Volknandt
- Institute for Cell Biology and Neuroscience, Department Molecular and Cellular Neurobiology, Max von Laue Str. 13, 60438 Frankfurt am Main, Germany.
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43
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Betke KM, Rose KL, Friedman DB, Baucum AJ, Hyde K, Schey KL, Hamm HE. Differential localization of G protein βγ subunits. Biochemistry 2014; 53:2329-43. [PMID: 24568373 PMCID: PMC4004276 DOI: 10.1021/bi500091p] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
G protein βγ subunits play essential roles in regulating cellular signaling cascades, yet little is known about their distribution in tissues or their subcellular localization. While previous studies have suggested specific isoforms may exhibit a wide range of distributions throughout the central nervous system, a thorough investigation of the expression patterns of both Gβ and Gγ isoforms within subcellular fractions has not been conducted. To address this, we applied a targeted proteomics approach known as multiple-reaction monitoring to analyze localization patterns of Gβ and Gγ isoforms in pre- and postsynaptic fractions isolated from cortex, cerebellum, hippocampus, and striatum. Particular Gβ and Gγ subunits were found to exhibit distinct regional and subcellular localization patterns throughout the brain. Significant differences in subcellular localization between pre- and postsynaptic fractions were observed within the striatum for most Gβ and Gγ isoforms, while others exhibited completely unique expression patterns in all four brain regions examined. Such differences are a prerequisite for understanding roles of individual subunits in regulating specific signaling pathways throughout the central nervous system.
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Affiliation(s)
- Katherine M Betke
- Department of Pharmacology, ‡Mass Spectrometry Research Center, §Department of Molecular Physiology and Biophysics, and ∥Department of Biochemistry, Vanderbilt University Medical Center , Nashville, Tennessee 37232-6600, United States
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44
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Poon VY, Goh C, Voorhoeve PM, Fivaz M. High-content imaging of presynaptic assembly. Front Cell Neurosci 2014; 8:66. [PMID: 24624059 PMCID: PMC3939450 DOI: 10.3389/fncel.2014.00066] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 02/13/2014] [Indexed: 11/15/2022] Open
Abstract
Presynaptic assembly involves the specialization of a patch of axonal membrane into a complex structure that supports synaptic vesicle exocytosis and neurotransmitter release. In mammalian neurons, presynaptic assembly is widely studied in a co-culture assay, where a synaptogenic cue expressed at the surface of a heterologous cell induces presynaptic differentiation in a contacting axon. This assay has led to the discovery of numerous synaptogenic proteins, but has not been used to probe neuronal mechanisms regulating presynaptic induction. The identification of regulatory pathways that fine-tune presynaptic assembly is hindered by the lack of adequate tools to quantitatively image this process. Here, we introduce an image-processing algorithm that identifies presynaptic clusters in mammalian co-cultures and extracts a range of synapse-specific parameters. Using this software, we assessed the intrinsic variability of this synaptic induction assay and probed the effect of eight neuronal microRNAs on presynaptic assembly. Our analysis revealed a novel role for miR-27b in augmenting the density of presynaptic clusters. Our software is applicable to a wide range of synaptic induction protocols (including spontaneous synaptogenesis observed in neuron cultures) and is a valuable tool to determine the subtle impact of disease-associated genes on presynaptic assembly.
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Affiliation(s)
- Vivian Y Poon
- Neuroscience and Behavioral Disorders Program, Duke-NUS Graduate Medical School , Singapore, Singapore
| | - Chiatzun Goh
- National University of Singapore Singapore, Singapore
| | - P Mathijs Voorhoeve
- Cancer and Stem Cell Biology Program, Duke-NUS Graduate Medical School Singapore, Singapore ; Department of Biochemistry, National University of Singapore Singapore, Singapore
| | - Marc Fivaz
- Neuroscience and Behavioral Disorders Program, Duke-NUS Graduate Medical School , Singapore, Singapore ; Department of Physiology, National University of Singapore Singapore, Singapore
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45
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Weingarten J, Lassek M, Mueller BF, Rohmer M, Lunger I, Baeumlisberger D, Dudek S, Gogesch P, Karas M, Volknandt W. The proteome of the presynaptic active zone from mouse brain. Mol Cell Neurosci 2014; 59:106-18. [PMID: 24534009 DOI: 10.1016/j.mcn.2014.02.003] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Revised: 02/05/2014] [Accepted: 02/07/2014] [Indexed: 01/07/2023] Open
Abstract
Neurotransmitter release as well as the structural and functional dynamics of the presynaptic active zone is controlled by proteinaceous components. Here we describe for the first time an experimental approach for the isolation of the presynaptic active zone from individual mouse brains, a prerequisite for understanding the functional inventory of the presynaptic protein network and for the later analysis of changes occurring in mutant mice. Using a monoclonal antibody against the ubiquitous synaptic vesicle protein SV2 we immunopurified synaptic vesicles docked to the presynaptic plasma membrane. Enrichment studies by means of Western blot analysis and mass spectrometry identified 485 proteins belonging to an impressive variety of functional categories. Our data suggest that presynaptic active zones represent focal hot spots that are not only involved in the regulation of neurotransmitter release but also in multiple structural and functional alterations the adult nerve terminal undergoes during neural activity in adult CNS. They furthermore open new avenues for characterizing alterations in the active zone proteome of mutant mice and their corresponding controls, including the various mouse models of neurological diseases.
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Affiliation(s)
- Jens Weingarten
- Institute for Cell Biology and Neuroscience, Biologicum, Goethe-University, Frankfurt am Main, Germany
| | - Melanie Lassek
- Institute for Cell Biology and Neuroscience, Biologicum, Goethe-University, Frankfurt am Main, Germany
| | - Benjamin F Mueller
- Institute of Pharmaceutical Chemistry, Cluster of Excellence "Macromolecular Complexes", Goethe-University, Frankfurt am Main, Germany
| | - Marion Rohmer
- Institute of Pharmaceutical Chemistry, Cluster of Excellence "Macromolecular Complexes", Goethe-University, Frankfurt am Main, Germany
| | - Ilaria Lunger
- Institute for Cell Biology and Neuroscience, Biologicum, Goethe-University, Frankfurt am Main, Germany
| | | | - Simone Dudek
- Institute for Cell Biology and Neuroscience, Biologicum, Goethe-University, Frankfurt am Main, Germany
| | - Patricia Gogesch
- Institute for Cell Biology and Neuroscience, Biologicum, Goethe-University, Frankfurt am Main, Germany
| | - Michael Karas
- Institute of Pharmaceutical Chemistry, Cluster of Excellence "Macromolecular Complexes", Goethe-University, Frankfurt am Main, Germany
| | - Walter Volknandt
- Institute for Cell Biology and Neuroscience, Biologicum, Goethe-University, Frankfurt am Main, Germany.
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Biesemann C, Grønborg M, Luquet E, Wichert SP, Bernard V, Bungers SR, Cooper B, Varoqueaux F, Li L, Byrne JA, Urlaub H, Jahn O, Brose N, Herzog E. Proteomic screening of glutamatergic mouse brain synaptosomes isolated by fluorescence activated sorting. EMBO J 2014; 33:157-70. [PMID: 24413018 DOI: 10.1002/embj.201386120] [Citation(s) in RCA: 97] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
For decades, neuroscientists have used enriched preparations of synaptic particles called synaptosomes to study synapse function. However, the interpretation of corresponding data is problematic as synaptosome preparations contain multiple types of synapses and non-synaptic neuronal and glial contaminants. We established a novel Fluorescence Activated Synaptosome Sorting (FASS) method that substantially improves conventional synaptosome enrichment protocols and enables high-resolution biochemical analyses of specific synapse subpopulations. Employing knock-in mice with fluorescent glutamatergic synapses, we show that FASS isolates intact ultrapure synaptosomes composed of a resealed presynaptic terminal and a postsynaptic density as assessed by light and electron microscopy. FASS synaptosomes contain bona fide glutamatergic synapse proteins but are almost devoid of other synapse types and extrasynaptic or glial contaminants. We identified 163 enriched proteins in FASS samples, of which FXYD6 and Tpd52 were validated as new synaptic proteins. FASS purification thus enables high-resolution biochemical analyses of specific synapse subpopulations in health and disease.
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Affiliation(s)
- Christoph Biesemann
- Department of Molecular Neurobiology, Max Planck Institute of Experimental Medicine, Göttingen, Germany
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47
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Barth J, Volknandt W. Proteomic investigations of the synaptic vesicle interactome. Expert Rev Proteomics 2014; 8:211-20. [DOI: 10.1586/epr.11.7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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The pattern of cortical dysfunction in a mouse model of a schizophrenia-related microdeletion. J Neurosci 2013; 33:14825-39. [PMID: 24027283 DOI: 10.1523/jneurosci.1611-13.2013] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
We used a mouse model of the schizophrenia-predisposing 22q11.2 microdeletion to evaluate how this genetic lesion affects cortical neural circuits at the synaptic, cellular, and molecular levels. Guided by cognitive deficits, we demonstrated that mutant mice display robust deficits in high-frequency synaptic transmission and short-term plasticity (synaptic depression and potentiation), as well as alterations in long-term plasticity and dendritic spine stability. Apart from previously reported reduction in dendritic complexity of layer 5 pyramidal neurons, altered synaptic plasticity occurs in the context of relatively circumscribed and often subtle cytoarchitectural changes in neuronal density and inhibitory neuron numbers. We confirmed the pronounced DiGeorge critical region 8 (Dgcr8)-dependent deficits in primary micro-RNA processing and identified additional changes in gene expression and RNA splicing that may underlie the effects of this mutation. Reduction in Dgcr8 levels appears to be a major driver of altered short-term synaptic plasticity in prefrontal cortex and working memory but not of long-term plasticity and cytoarchitecture. Our findings inform the cortical synaptic and neuronal mechanisms of working memory impairment in the context of psychiatric disorders. They also provide insight into the link between micro-RNA dysregulation and genetic liability to schizophrenia and cognitive dysfunction.
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49
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Shetty A, Sytnyk V, Leshchyns'ka I, Puchkov D, Haucke V, Schachner M. The neural cell adhesion molecule promotes maturation of the presynaptic endocytotic machinery by switching synaptic vesicle recycling from adaptor protein 3 (AP-3)- to AP-2-dependent mechanisms. J Neurosci 2013; 33:16828-45. [PMID: 24133283 PMCID: PMC6618524 DOI: 10.1523/jneurosci.2192-13.2013] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2013] [Revised: 08/27/2013] [Accepted: 09/13/2013] [Indexed: 02/05/2023] Open
Abstract
Newly formed synapses undergo maturation during ontogenetic development via mechanisms that remain poorly understood. We show that maturation of the presynaptic endocytotic machinery in CNS neurons requires substitution of the adaptor protein 3 (AP-3) with AP-2 at the presynaptic plasma membrane. In mature synapses, AP-2 associates with the intracellular domain of the neural cell adhesion molecule (NCAM). NCAM promotes binding of AP-2 over binding of AP-3 to presynaptic membranes, thus favoring the substitution of AP-3 for AP-2 during formation of mature synapses. The presynaptic endocytotic machinery remains immature in adult NCAM-deficient (NCAM-/-) mice accumulating AP-3 instead of AP-2 and its partner protein AP180 in synaptic membranes and vesicles. NCAM deficiency or disruption of the NCAM/AP-2 complex in wild-type (NCAM+/+) neurons by overexpression of AP-2 binding-defective mutant NCAM interferes with efficient retrieval of the synaptic vesicle v-SNARE synaptobrevin 2. Abnormalities in synaptic vesicle endocytosis and recycling may thus contribute to neurological disorders associated with mutations in NCAM.
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Affiliation(s)
- Aparna Shetty
- Zentrum für Molekulare Neurobiologie, Universität Hamburg, 20246 Hamburg, Germany
| | - Vladimir Sytnyk
- Zentrum für Molekulare Neurobiologie, Universität Hamburg, 20246 Hamburg, Germany
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Iryna Leshchyns'ka
- Zentrum für Molekulare Neurobiologie, Universität Hamburg, 20246 Hamburg, Germany
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Dmytro Puchkov
- Zentrum für Molekulare Neurobiologie, Universität Hamburg, 20246 Hamburg, Germany
| | - Volker Haucke
- Leibniz Institut für Molekulare Pharmakologie and Freie Universität Berlin, 13125 Berlin, Germany
| | - Melitta Schachner
- Zentrum für Molekulare Neurobiologie, Universität Hamburg, 20246 Hamburg, Germany
- Keck Center for Collaborative Neuroscience, Rutgers University, Piscataway, New Jersey 08854-8082, and
- Center for Neuroscience, Shantou University Medical College, Shantou 515041, People's Republic of China
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50
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Abstract
The vesicular glutamate transporters (VGLUTs) package glutamate into synaptic vesicles, and the two principal isoforms VGLUT1 and VGLUT2 have been suggested to influence the properties of release. To understand how a VGLUT isoform might influence transmitter release, we have studied their trafficking and previously identified a dileucine-like endocytic motif in the C terminus of VGLUT1. Disruption of this motif impairs the activity-dependent recycling of VGLUT1, but does not eliminate its endocytosis. We now report the identification of two additional dileucine-like motifs in the N terminus of VGLUT1 that are not well conserved in the other isoforms. In the absence of all three motifs, rat VGLUT1 shows limited accumulation at synaptic sites and no longer responds to stimulation. In addition, shRNA-mediated knockdown of clathrin adaptor proteins AP-1 and AP-2 shows that the C-terminal motif acts largely via AP-2, whereas the N-terminal motifs use AP-1. Without the C-terminal motif, knockdown of AP-1 reduces the proportion of VGLUT1 that responds to stimulation. VGLUT1 thus contains multiple sorting signals that engage distinct trafficking mechanisms. In contrast to VGLUT1, the trafficking of VGLUT2 depends almost entirely on the conserved C-terminal dileucine-like motif: without this motif, a substantial fraction of VGLUT2 redistributes to the plasma membrane and the transporter's synaptic localization is disrupted. Consistent with these differences in trafficking signals, wild-type VGLUT1 and VGLUT2 differ in their response to stimulation.
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