1
|
Cuentas-Condori A, Chen S, Krout M, Gallik KL, Tipps J, Gailey C, Flautt L, Kim H, Mulcahy B, Zhen M, Richmond JE, Miller DM. The epithelial Na + channel UNC-8 promotes an endocytic mechanism that recycles presynaptic components to new boutons in remodeling neurons. Cell Rep 2023; 42:113327. [PMID: 37906594 PMCID: PMC10921563 DOI: 10.1016/j.celrep.2023.113327] [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: 08/18/2022] [Revised: 06/01/2023] [Accepted: 10/06/2023] [Indexed: 11/02/2023] Open
Abstract
Circuit refinement involves the formation of new presynaptic boutons as others are dismantled. Nascent presynaptic sites can incorporate material from recently eliminated synapses, but the recycling mechanisms remain elusive. In early-stage C. elegans larvae, the presynaptic boutons of GABAergic DD neurons are removed and new outputs established at alternative sites. Here, we show that developmentally regulated expression of the epithelial Na+ channel (ENaC) UNC-8 in remodeling DD neurons promotes a Ca2+ and actin-dependent mechanism, involving activity-dependent bulk endocytosis (ADBE), that recycles presynaptic material for reassembly at nascent DD synapses. ADBE normally functions in highly active neurons to accelerate local recycling of synaptic vesicles. In contrast, we find that an ADBE-like mechanism results in the distal recycling of synaptic material from old to new synapses. Thus, our findings suggest that a native mechanism (ADBE) can be repurposed to dismantle presynaptic terminals for reassembly at new, distant locations.
Collapse
Affiliation(s)
- Andrea Cuentas-Condori
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Siqi Chen
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Mia Krout
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Kristin L Gallik
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - John Tipps
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Casey Gailey
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Leah Flautt
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Hongkyun Kim
- Department of Cell Biology and Anatomy, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064, USA
| | - Ben Mulcahy
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON M5G 1X5, Canada
| | - Mei Zhen
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON M5G 1X5, Canada
| | - Janet E Richmond
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - David M Miller
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37240, USA; Neurosience Program, Vanderbilt University, Nashville, TN 37240, USA.
| |
Collapse
|
2
|
Rizalar FS, Lucht MT, Petzoldt A, Kong S, Sun J, Vines JH, Telugu NS, Diecke S, Kaas T, Bullmann T, Schmied C, Löwe D, King JS, Cho W, Hallermann S, Puchkov D, Sigrist SJ, Haucke V. Phosphatidylinositol 3,5-bisphosphate facilitates axonal vesicle transport and presynapse assembly. Science 2023; 382:223-230. [PMID: 37824668 PMCID: PMC10938084 DOI: 10.1126/science.adg1075] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 08/16/2023] [Indexed: 10/14/2023]
Abstract
Neurons relay information via specialized presynaptic compartments for neurotransmission. Unlike conventional organelles, the specialized apparatus characterizing the neuronal presynapse must form de novo. How the components for presynaptic neurotransmission are transported and assembled is poorly understood. Our results show that the rare late endosomal signaling lipid phosphatidylinositol 3,5-bisphosphate [PI(3,5)P2] directs the axonal cotransport of synaptic vesicle and active zone proteins in precursor vesicles in human neurons. Precursor vesicles are distinct from conventional secretory organelles, endosomes, and degradative lysosomes and are transported by coincident detection of PI(3,5)P2 and active ARL8 via kinesin KIF1A to the presynaptic compartment. Our findings identify a crucial mechanism that mediates the delivery of synaptic vesicle and active zone proteins to developing synapses.
Collapse
Affiliation(s)
- Filiz Sila Rizalar
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Rössle-Str. 10, 13125 Berlin, Germany
| | - Max T. Lucht
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Rössle-Str. 10, 13125 Berlin, Germany
| | - Astrid Petzoldt
- Department of Biology, Chemistry, Pharmacy, Freie Universität Berlin, 14195 Berlin, Germany
| | - Shuhan Kong
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Rössle-Str. 10, 13125 Berlin, Germany
| | - Jiachen Sun
- Department of Chemistry, University of Illinois Chicago, Chicago, IL 60607, USA
| | - James H. Vines
- School of Biosciences, University of Sheffield, Firth Court Western Bank, Sheffield S10 2TN, UK
| | - Narasimha Swamy Telugu
- Max-Delbrück-Centrum für Molekulare Medizin (MDC), Technology Platform Pluripotent Stem Cells, Robert-Rössle-Straße 10, 13125 Berlin, Germany
| | - Sebastian Diecke
- Max-Delbrück-Centrum für Molekulare Medizin (MDC), Technology Platform Pluripotent Stem Cells, Robert-Rössle-Straße 10, 13125 Berlin, Germany
| | - Thomas Kaas
- Leipzig University, Carl-Ludwig-Institute of Physiology, Faculty of Medicine, 04103 Leipzig, Germany
| | - Torsten Bullmann
- Leipzig University, Carl-Ludwig-Institute of Physiology, Faculty of Medicine, 04103 Leipzig, Germany
| | - Christopher Schmied
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Rössle-Str. 10, 13125 Berlin, Germany
| | - Delia Löwe
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Rössle-Str. 10, 13125 Berlin, Germany
| | - Jason S. King
- School of Biosciences, University of Sheffield, Firth Court Western Bank, Sheffield S10 2TN, UK
| | - Wonhwa Cho
- Department of Chemistry, University of Illinois Chicago, Chicago, IL 60607, USA
| | - Stefan Hallermann
- Leipzig University, Carl-Ludwig-Institute of Physiology, Faculty of Medicine, 04103 Leipzig, Germany
| | - Dmytro Puchkov
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Rössle-Str. 10, 13125 Berlin, Germany
| | - Stephan J. Sigrist
- Department of Biology, Chemistry, Pharmacy, Freie Universität Berlin, 14195 Berlin, Germany
| | - Volker Haucke
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Rössle-Str. 10, 13125 Berlin, Germany
- Department of Biology, Chemistry, Pharmacy, Freie Universität Berlin, 14195 Berlin, Germany
- Charité – Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| |
Collapse
|
3
|
Willig KI. In vivo super-resolution of the brain - How to visualize the hidden nanoplasticity? iScience 2022; 25:104961. [PMID: 36093060 PMCID: PMC9449647 DOI: 10.1016/j.isci.2022.104961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Super-resolution fluorescence microscopy has entered most biological laboratories worldwide and its benefit is undisputable. Its application to brain imaging, for example in living mice, enables the study of sub-cellular structural plasticity and brain function directly in a living mammal. The demands of brain imaging on the different super-resolution microscopy techniques (STED, RESOLFT, SIM, ISM) and labeling strategies are discussed here as well as the challenges of the required cranial window preparation. Applications of super-resolution in the anesthetized mouse brain enlighten the stability and plasticity of synaptic nanostructures. These studies show the potential of in vivo super-resolution imaging and justify its application more widely in vivo to investigate the role of nanostructures in memory and learning.
Collapse
Affiliation(s)
- Katrin I Willig
- Group of Optical Nanoscopy in Neuroscience, Max Planck Institute for Multidisciplinary Sciences, City Campus, Göttingen, Germany
| |
Collapse
|
4
|
Isolation, cryo-laser scanning confocal microscope imaging and cryo-FIB milling of mouse glutamatergic synaptosomes. PLoS One 2022; 17:e0271799. [PMID: 35960737 PMCID: PMC9374259 DOI: 10.1371/journal.pone.0271799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 07/07/2022] [Indexed: 11/19/2022] Open
Abstract
Ionotropic glutamate receptors (iGluRs) at postsynaptic terminals mediate the majority of fast excitatory neurotransmission in response to release of glutamate from the presynaptic terminal. Obtaining structural information on the molecular organization of iGluRs in their native environment, along with other signaling and scaffolding proteins in the postsynaptic density (PSD), and associated proteins on the presynaptic terminal, would enhance understanding of the molecular basis for excitatory synaptic transmission in normal and in disease states. Cryo-electron tomography (ET) studies of synaptosomes is one attractive vehicle by which to study iGluR-containing excitatory synapses. Here we describe a workflow for the preparation of glutamatergic synaptosomes for cryo-ET studies. We describe the utilization of fluorescent markers for the facile detection of the pre and postsynaptic terminals of glutamatergic synaptosomes using cryo-laser scanning confocal microscope (cryo-LSM). We further provide the details for preparation of lamellae, between ~100 to 200 nm thick, of glutamatergic synaptosomes using cryo-focused ion-beam (FIB) milling. We monitor the lamella preparation using a scanning electron microscope (SEM) and following lamella production, we identify regions for subsequent cryo-ET studies by confocal fluorescent imaging, exploiting the pre and postsynaptic fluorophores.
Collapse
|
5
|
Paget-Blanc V, Pfeffer ME, Pronot M, Lapios P, Angelo MF, Walle R, Cordelières FP, Levet F, Claverol S, Lacomme S, Petrel M, Martin C, Pitard V, De Smedt Peyrusse V, Biederer T, Perrais D, Trifilieff P, Herzog E. A synaptomic analysis reveals dopamine hub synapses in the mouse striatum. Nat Commun 2022; 13:3102. [PMID: 35660742 PMCID: PMC9166739 DOI: 10.1038/s41467-022-30776-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 05/18/2022] [Indexed: 11/13/2022] Open
Abstract
Dopamine transmission is involved in reward processing and motor control, and its impairment plays a central role in numerous neurological disorders. Despite its strong pathophysiological relevance, the molecular and structural organization of the dopaminergic synapse remains to be established. Here, we used targeted labelling and fluorescence activated sorting to purify striatal dopaminergic synaptosomes. We provide the proteome of dopaminergic synapses with 57 proteins specifically enriched. Beyond canonical markers of dopamine neurotransmission such as dopamine biosynthetic enzymes and cognate receptors, we validated 6 proteins not previously described as enriched. Moreover, our data reveal the adhesion of dopaminergic synapses to glutamatergic, GABAergic or cholinergic synapses in structures we named “dopamine hub synapses”. At glutamatergic synapses, pre- and postsynaptic markers are significantly increased upon association with dopamine synapses. Dopamine hub synapses may thus support local dopaminergic signalling, complementing volume transmission thought to be the major mechanism by which monoamines modulate network activity. The neurotransmitter dopamine is an important regulator of brain function. Here the authors describe “dopamine hub synapses”, where dopamine transmission may act in synergy with other neurotransmitters.
Collapse
Affiliation(s)
- Vincent Paget-Blanc
- Univ. Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, F-33000, Bordeaux, France
| | - Marlene E Pfeffer
- Univ. Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, F-33000, Bordeaux, France
| | - Marie Pronot
- Univ. Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, F-33000, Bordeaux, France
| | - Paul Lapios
- Univ. Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, F-33000, Bordeaux, France
| | - Maria-Florencia Angelo
- Univ. Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, F-33000, Bordeaux, France
| | - Roman Walle
- Univ. Bordeaux, INRAE, Bordeaux INP, NutriNeuro, UMR 1286, F-33000, Bordeaux, France
| | - Fabrice P Cordelières
- Univ. Bordeaux, CNRS, INSERM, Bordeaux Imaging Center, BIC, UAR 3420, US 4, F-33000, Bordeaux, France
| | - Florian Levet
- Univ. Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, F-33000, Bordeaux, France.,Univ. Bordeaux, CNRS, INSERM, Bordeaux Imaging Center, BIC, UAR 3420, US 4, F-33000, Bordeaux, France
| | | | - Sabrina Lacomme
- Univ. Bordeaux, CNRS, INSERM, Bordeaux Imaging Center, BIC, UAR 3420, US 4, F-33000, Bordeaux, France
| | - Mélina Petrel
- Univ. Bordeaux, CNRS, INSERM, Bordeaux Imaging Center, BIC, UAR 3420, US 4, F-33000, Bordeaux, France
| | - Christelle Martin
- Univ. Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, F-33000, Bordeaux, France
| | - Vincent Pitard
- UB'FACSility CNRS UMS 3427, INSERM US 005, Univ. Bordeaux, F-33000, Bordeaux, France
| | | | - Thomas Biederer
- Department of Neurology, Yale School of Medicine, New Haven, CT, 06511, USA
| | - David Perrais
- Univ. Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, F-33000, Bordeaux, France
| | - Pierre Trifilieff
- Univ. Bordeaux, INRAE, Bordeaux INP, NutriNeuro, UMR 1286, F-33000, Bordeaux, France
| | - Etienne Herzog
- Univ. Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, F-33000, Bordeaux, France.
| |
Collapse
|
6
|
Ivanova D, Cousin MA. Synaptic Vesicle Recycling and the Endolysosomal System: A Reappraisal of Form and Function. Front Synaptic Neurosci 2022; 14:826098. [PMID: 35280702 PMCID: PMC8916035 DOI: 10.3389/fnsyn.2022.826098] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 02/03/2022] [Indexed: 12/15/2022] Open
Abstract
The endolysosomal system is present in all cell types. Within these cells, it performs a series of essential roles, such as trafficking and sorting of membrane cargo, intracellular signaling, control of metabolism and degradation. A specific compartment within central neurons, called the presynapse, mediates inter-neuronal communication via the fusion of neurotransmitter-containing synaptic vesicles (SVs). The localized recycling of SVs and their organization into functional pools is widely assumed to be a discrete mechanism, that only intersects with the endolysosomal system at specific points. However, evidence is emerging that molecules essential for endolysosomal function also have key roles within the SV life cycle, suggesting that they form a continuum rather than being isolated processes. In this review, we summarize the evidence for key endolysosomal molecules in SV recycling and propose an alternative model for membrane trafficking at the presynapse. This includes the hypotheses that endolysosomal intermediates represent specific functional SV pools, that sorting of cargo to SVs is mediated via the endolysosomal system and that manipulation of this process can result in both plastic changes to neurotransmitter release and pathophysiology via neurodegeneration.
Collapse
Affiliation(s)
- Daniela Ivanova
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Muir Maxwell Epilepsy Centre, University of Edinburgh, Edinburgh, United Kingdom
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, United Kingdom
- *Correspondence: Daniela Ivanova,
| | - Michael A. Cousin
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Muir Maxwell Epilepsy Centre, University of Edinburgh, Edinburgh, United Kingdom
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, United Kingdom
- Michael A. Cousin,
| |
Collapse
|
7
|
Huang G, Zang J, He L, Zhu H, Huang J, Yuan Z, Chen T, Xu A. Bioactive Nanoenzyme Reverses Oxidative Damage and Endoplasmic Reticulum Stress in Neurons under Ischemic Stroke. ACS NANO 2022; 16:431-452. [PMID: 34958560 DOI: 10.1021/acsnano.1c07205] [Citation(s) in RCA: 74] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Designing translational antioxidative agents that could scavenge free radicals produced during reperfusion in brain ischemia stroke and alleviate neurologic damage is the main objective for ischemic stroke treatment. Herein, we explored and simply synthesized a biomimic and translational Mn3O4 nanoenzyme (HSA-Mn3O4) to constrain ischemic stroke reperfusion-induced nervous system injury. This nanosystem exhibits reduced levels of inflammation and prolonged circulation time and potent ROS scavenging activities. As expected, HSA-Mn3O4 effectively inhibits oxygen and glucose deprivation-mediated cell apoptosis and endoplasmic reticulum stress and demonstrates neuroprotective capacity against ischemic stroke and reperfusion injury of brain tissue. Furthermore, HSA-Mn3O4 effectively releases Mn ions and promotes the increase of superoxide dismutase 2 activity. Therefore, HSA-Mn3O4 inhibits brain tissue damage by restraining cell apoptosis and endoplasmic reticulum stress in vivo. Taken together, this study not only sheds light on design of biomimic and translational nanomedicine but also reveals the neuroprotective action mechanisms against ischemic stroke and reperfusion injury.
Collapse
Affiliation(s)
- Guanning Huang
- Department of Neurology and Stroke Center, The First Affiliated Hospital and Department of Chemistry, Jinan University, Guangzhou 510632, P.R. China
| | - Jiankun Zang
- Department of Neurology and Stroke Center, The First Affiliated Hospital and Department of Chemistry, Jinan University, Guangzhou 510632, P.R. China
| | - Lizhen He
- Department of Neurology and Stroke Center, The First Affiliated Hospital and Department of Chemistry, Jinan University, Guangzhou 510632, P.R. China
| | - Huili Zhu
- Department of Neurology and Stroke Center, The First Affiliated Hospital and Department of Chemistry, Jinan University, Guangzhou 510632, P.R. China
| | - Jiarun Huang
- Department of Neurology and Stroke Center, The First Affiliated Hospital and Department of Chemistry, Jinan University, Guangzhou 510632, P.R. China
| | - Zhongwen Yuan
- Department of Neurology and Stroke Center, The First Affiliated Hospital and Department of Chemistry, Jinan University, Guangzhou 510632, P.R. China
| | - Tianfeng Chen
- Department of Neurology and Stroke Center, The First Affiliated Hospital and Department of Chemistry, Jinan University, Guangzhou 510632, P.R. China
| | - Anding Xu
- Department of Neurology and Stroke Center, The First Affiliated Hospital and Department of Chemistry, Jinan University, Guangzhou 510632, P.R. China
| |
Collapse
|
8
|
Hobson BD, Kong L, Angelo MF, Lieberman OJ, Mosharov EV, Herzog E, Sulzer D, Sims PA. Subcellular and regional localization of mRNA translation in midbrain dopamine neurons. Cell Rep 2022; 38:110208. [PMID: 35021090 PMCID: PMC8844886 DOI: 10.1016/j.celrep.2021.110208] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 10/25/2021] [Accepted: 12/13/2021] [Indexed: 12/12/2022] Open
Abstract
Midbrain dopaminergic (mDA) neurons exhibit extensive dendritic and axonal arborizations, but local protein synthesis is not characterized in these neurons. Here, we investigate messenger RNA (mRNA) localization and translation in mDA neuronal axons and dendrites, both of which release dopamine (DA). Using highly sensitive ribosome-bound RNA sequencing and imaging approaches, we find no evidence for mRNA translation in mDA axons. In contrast, mDA neuronal dendrites in the substantia nigra pars reticulata (SNr) contain ribosomes and mRNAs encoding the major components of DA synthesis, release, and reuptake machinery. Surprisingly, we also observe dendritic localization of mRNAs encoding synaptic vesicle-related proteins, including those involved in exocytic fusion. Our results are consistent with a role for local translation in the regulation of DA release from dendrites, but not from axons. Our translatome data define a molecular signature of sparse mDA neurons in the SNr, including the enrichment of Atp2a3/SERCA3, an atypical ER calcium pump.
Collapse
Affiliation(s)
- Benjamin D Hobson
- Department of Systems Biology, Columbia University Irving Medical Center, New York 10032, NY, USA; Medical Scientist Training Program, Columbia University Irving Medical Center, New York, NY 10032, USA; Department of Psychiatry, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Linghao Kong
- Department of Systems Biology, Columbia University Irving Medical Center, New York 10032, NY, USA
| | - Maria Florencia Angelo
- Interdisciplinary Institute for Neuroscience, Université de Bordeaux, Bordeaux, France; Interdisciplinary Institute for Neuroscience, CNRS UMR 5297, Bordeaux, France
| | - Ori J Lieberman
- Medical Scientist Training Program, Columbia University Irving Medical Center, New York, NY 10032, USA; Department of Psychiatry, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Eugene V Mosharov
- Department of Psychiatry, Columbia University Irving Medical Center, New York, NY 10032, USA; Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY 10032, USA
| | - Etienne Herzog
- Interdisciplinary Institute for Neuroscience, Université de Bordeaux, Bordeaux, France; Interdisciplinary Institute for Neuroscience, CNRS UMR 5297, Bordeaux, France.
| | - David Sulzer
- Department of Neurology, Columbia University Irving Medical Center, New York, NY 10032, USA; Department of Psychiatry, Columbia University Irving Medical Center, New York, NY 10032, USA; Department of Pharmacology, Columbia University Irving Medical Center, New York, NY 10032, USA; Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY 10032, USA; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD, USA.
| | - Peter A Sims
- Department of Systems Biology, Columbia University Irving Medical Center, New York 10032, NY, USA; Department of Biochemistry & Molecular Biophysics, Columbia University Irving Medical Center, New York, NY 10032, USA; Sulzberger Columbia Genome Center, Columbia University Irving Medical Center, New York, NY 10032, USA; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD, USA.
| |
Collapse
|
9
|
Patzke C, Dai J, Brockmann MM, Sun Z, Fenske P, Rosenmund C, Südhof TC. Cannabinoid receptor activation acutely increases synaptic vesicle numbers by activating synapsins in human synapses. Mol Psychiatry 2021; 26:6253-6268. [PMID: 33931733 DOI: 10.1038/s41380-021-01095-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 03/20/2021] [Accepted: 03/31/2021] [Indexed: 02/03/2023]
Abstract
Cannabis and cannabinoid drugs are central agents that are used widely recreationally and are employed broadly for treating psychiatric conditions. Cannabinoids primarily act by stimulating presynaptic CB1 receptors (CB1Rs), the most abundant G-protein-coupled receptors in brain. CB1R activation decreases neurotransmitter release by inhibiting presynaptic Ca2+ channels and induces long-term plasticity by decreasing cellular cAMP levels. Here we identified an unanticipated additional mechanism of acute cannabinoid signaling in presynaptic terminals that regulates the size of synaptic vesicle pools available for neurotransmitter release. Specifically, we show that activation of CB1Rs in human and mouse neurons rapidly recruits vesicles to nerve terminals by suppressing the cAMP-dependent phosphorylation of synapsins. We confirmed this unanticipated mechanism using conditional deletion of synapsin-1, the predominant synapsin isoform in human neurons, demonstrating that synapsin-1 significantly contributes to the CB1R-dependent regulation of neurotransmission. Interestingly, acute activation of the Gi-DREADD hM4D mimics the effect of CB1R activation in a synapsin-1-dependent manner, suggesting that the control of synaptic vesicle numbers by synapsin-1 phosphorylation is a general presynaptic mechanism of neuromodulation. Thus, we uncovered a CB1R-dependent presynaptic mechanism that rapidly regulates the organization and neurotransmitter release properties of synapses.
Collapse
Affiliation(s)
- Christopher Patzke
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA, 94305, USA. .,Department of Biological Sciences, Boler-Parseghian Center for Rare and Neglected Diseases, University of Notre Dame, 109A Galvin Life Science Center, Notre Dame, IN, 46556, USA.
| | - Jinye Dai
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA, 94305, USA.,Howard Hughes Medical Institute, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA, 94305, USA
| | - Marisa M Brockmann
- Institute of Neurophysiology, Charité Universitätsmedizin, 10117, Berlin, Germany
| | - Zijun Sun
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA, 94305, USA
| | - Pascal Fenske
- Institute of Neurophysiology, Charité Universitätsmedizin, 10117, Berlin, Germany
| | - Christian Rosenmund
- Institute of Neurophysiology, Charité Universitätsmedizin, 10117, Berlin, Germany
| | - Thomas C Südhof
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA, 94305, USA.,Howard Hughes Medical Institute, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA, 94305, USA
| |
Collapse
|
10
|
Zhong H, Ceballos CC, Massengill CI, Muniak MA, Ma L, Qin M, Petrie SK, Mao T. High-fidelity, efficient, and reversible labeling of endogenous proteins using CRISPR-based designer exon insertion. eLife 2021; 10:64911. [PMID: 34100715 PMCID: PMC8211447 DOI: 10.7554/elife.64911] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Accepted: 06/07/2021] [Indexed: 12/26/2022] Open
Abstract
Precise and efficient insertion of large DNA fragments into somatic cells using gene editing technologies to label or modify endogenous proteins remains challenging. Non-specific insertions/deletions (INDELs) resulting from the non-homologous end joining pathway make the process error-prone. Further, the insert is not readily removable. Here, we describe a method called CRISPR-mediated insertion of exon (CRISPIE) that can precisely and reversibly label endogenous proteins using CRISPR/Cas9-based editing. CRISPIE inserts a designer donor module, which consists of an exon encoding the protein sequence flanked by intron sequences, into an intronic location in the target gene. INDELs at the insertion junction will be spliced out, leaving mRNAs nearly error-free. We used CRISPIE to fluorescently label endogenous proteins in mammalian neurons in vivo with previously unachieved efficiency. We demonstrate that this method is broadly applicable, and that the insert can be readily removed later. CRISPIE permits protein sequence insertion with high fidelity, efficiency, and flexibility.
Collapse
Affiliation(s)
- Haining Zhong
- Vollum Institute, Oregon Health & Science University, Portland, United States
| | - Cesar C Ceballos
- Vollum Institute, Oregon Health & Science University, Portland, United States
| | | | - Michael A Muniak
- Vollum Institute, Oregon Health & Science University, Portland, United States
| | - Lei Ma
- Vollum Institute, Oregon Health & Science University, Portland, United States
| | - Maozhen Qin
- Vollum Institute, Oregon Health & Science University, Portland, United States
| | - Stefanie Kaech Petrie
- Department of Neurology, Oregon Health & Science University, Portland, United States
| | - Tianyi Mao
- Vollum Institute, Oregon Health & Science University, Portland, United States
| |
Collapse
|
11
|
Zhang XM, Cordelieres FP, Herzog E. Investigate Synaptic Vesicles Mobility in Neuronal Culture Axons by FRAP Imaging. Bio Protoc 2021; 11:e3962. [PMID: 33855120 DOI: 10.21769/bioprotoc.3962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 01/19/2021] [Accepted: 01/27/2021] [Indexed: 11/02/2022] Open
Abstract
Synaptic vesicles (SVs) are clustered in the presynaptic terminals and consistently trafficking along axons. Based on their release features, SVs are classified into different "pools". Imaging of SVs that are traveling among multiple presynaptic terminals has helped define a new pool named "SV super-pool". Here we describe a Fluorescent Recovery After Photobleaching (FRAP) approach to elucidate the relationship between SVs from the super-pool with SV clusters at presynaptic terminals. This method is powerful to investigate SV mobility regulation mechanisms.
Collapse
Affiliation(s)
- Xiao Min Zhang
- Department of Pathophysiology, Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Fabrice P Cordelieres
- University Bordeaux, CNRS, INSERM, Bordeaux Imaging Center, BIC, UMS, Bordeaux, France
| | - Etienne Herzog
- University Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR, Bordeaux, France
| |
Collapse
|
12
|
Kouwenhoven WM, Fortin G, Penttinen AM, Florence C, Delignat-Lavaud B, Bourque MJ, Trimbuch T, Luppi MP, Salvail-Lacoste A, Legault P, Poulin JF, Rosenmund C, Awatramani R, Trudeau LÉ. VGluT2 Expression in Dopamine Neurons Contributes to Postlesional Striatal Reinnervation. J Neurosci 2020; 40:8262-8275. [PMID: 32928885 PMCID: PMC7577590 DOI: 10.1523/jneurosci.0823-20.2020] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 08/14/2020] [Accepted: 09/07/2020] [Indexed: 11/21/2022] Open
Abstract
A subset of adult ventral tegmental area dopamine (DA) neurons expresses vesicular glutamate transporter 2 (VGluT2) and releases glutamate as a second neurotransmitter in the striatum, while only few adult substantia nigra DA neurons have this capacity. Recent work showed that cellular stress created by neurotoxins such as MPTP and 6-hydroxydopamine can upregulate VGluT2 in surviving DA neurons, suggesting the possibility of a role in cell survival, although a high level of overexpression could be toxic to DA neurons. Here we examined the level of VGluT2 upregulation in response to neurotoxins and its impact on postlesional plasticity. We first took advantage of an in vitro neurotoxin model of Parkinson's disease and found that this caused an average 2.5-fold enhancement of Vglut2 mRNA in DA neurons. This could represent a reactivation of a developmental phenotype because using an intersectional genetic lineage-mapping approach, we find that >98% of DA neurons have a VGluT2+ lineage. Expression of VGluT2 was detectable in most DA neurons at embryonic day 11.5 and was localized in developing axons. Finally, compatible with the possibility that enhanced VGluT2 expression in DA neurons promotes axonal outgrowth and reinnervation in the postlesional brain, we observed that DA neurons in female and male mice in which VGluT2 was conditionally removed established fewer striatal connections 7 weeks after a neurotoxin lesion. Thus, we propose here that the developmental expression of VGluT2 in DA neurons can be reactivated at postnatal stages, contributing to postlesional plasticity of dopaminergic axons.SIGNIFICANCE STATEMENT A small subset of dopamine neurons in the adult, healthy brain expresses vesicular glutamate transporter 2 (VGluT2) and thus releases glutamate as a second neurotransmitter in the striatum. This neurochemical phenotype appears to be plastic as exposure to neurotoxins, such as 6-OHDA or MPTP, that model certain aspects of Parkinson's disease pathophysiology, boosts VGluT2 expression in surviving dopamine neurons. Here we show that this enhanced VGluT2 expression in dopamine neurons drives axonal outgrowth and contributes to dopamine neuron axonal plasticity in the postlesional brain. A better understanding of the neurochemical changes that occur during the progression of Parkinson's disease pathology will aid the development of novel therapeutic strategies for this disease.
Collapse
Affiliation(s)
- Willemieke M Kouwenhoven
- Department of Pharmacology and Physiology, Department of Neurosciences, Groupe de Recherche sur le Système Nerveux Central, Faculty of Medicine, Université de Montréal, Montréal, Québec H3C 3J7, Canada
| | - Guillaume Fortin
- Department of Pharmacology and Physiology, Department of Neurosciences, Groupe de Recherche sur le Système Nerveux Central, Faculty of Medicine, Université de Montréal, Montréal, Québec H3C 3J7, Canada
| | - Anna-Maija Penttinen
- Department of Pharmacology and Physiology, Department of Neurosciences, Groupe de Recherche sur le Système Nerveux Central, Faculty of Medicine, Université de Montréal, Montréal, Québec H3C 3J7, Canada
| | - Clélia Florence
- Department of Pharmacology and Physiology, Department of Neurosciences, Groupe de Recherche sur le Système Nerveux Central, Faculty of Medicine, Université de Montréal, Montréal, Québec H3C 3J7, Canada
| | - Benoît Delignat-Lavaud
- Department of Pharmacology and Physiology, Department of Neurosciences, Groupe de Recherche sur le Système Nerveux Central, Faculty of Medicine, Université de Montréal, Montréal, Québec H3C 3J7, Canada
| | - Marie-Josée Bourque
- Department of Pharmacology and Physiology, Department of Neurosciences, Groupe de Recherche sur le Système Nerveux Central, Faculty of Medicine, Université de Montréal, Montréal, Québec H3C 3J7, Canada
| | - Thorsten Trimbuch
- Institut für Neurophysiologie, Charite Universitaetsmedizin, 10117 Berlin, Germany
| | - Milagros Pereira Luppi
- Department of Neurology and the Center for Genetic Medicine, Northwestern University, Chicago, Illinois 60611
| | - Alix Salvail-Lacoste
- Department of Biochemistry and Molecular Medicine, Faculty of Medicine, Université de Montréal, Montréal, Québec H3C 3J7, Canada
| | - Pascale Legault
- Department of Biochemistry and Molecular Medicine, Faculty of Medicine, Université de Montréal, Montréal, Québec H3C 3J7, Canada
| | - Jean-François Poulin
- Department of Neurology and the Center for Genetic Medicine, Northwestern University, Chicago, Illinois 60611
| | - Christian Rosenmund
- Institut für Neurophysiologie, Charite Universitaetsmedizin, 10117 Berlin, Germany
| | - Raj Awatramani
- Department of Neurology and the Center for Genetic Medicine, Northwestern University, Chicago, Illinois 60611
| | - Louis-Éric Trudeau
- Department of Pharmacology and Physiology, Department of Neurosciences, Groupe de Recherche sur le Système Nerveux Central, Faculty of Medicine, Université de Montréal, Montréal, Québec H3C 3J7, Canada
| |
Collapse
|
13
|
Chenouard N, Xuan F, Tsien RW. Synaptic vesicle traffic is supported by transient actin filaments and regulated by PKA and NO. Nat Commun 2020; 11:5318. [PMID: 33087709 PMCID: PMC7578807 DOI: 10.1038/s41467-020-19120-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Accepted: 09/25/2020] [Indexed: 11/10/2022] Open
Abstract
Synaptic vesicles (SVs) can be pooled across multiple synapses, prompting questions about their dynamic allocation for neurotransmission and plasticity. We find that the axonal traffic of recycling vesicles is not supported by ubiquitous microtubule-based motility but relies on actin instead. Vesicles freed from synaptic clusters undergo ~1 µm bouts of active transport, initiated by nearby elongation of actin filaments. Long distance translocation arises when successive bouts of active transport were linked by periods of free diffusion. The availability of SVs for active transport can be promptly increased by protein kinase A, a key player in neuromodulation. Vesicle motion is in turn impeded by shutting off axonal actin polymerization, mediated by nitric oxide-cyclic GMP signaling leading to inhibition of RhoA. These findings provide a potential framework for coordinating post-and pre-synaptic strength, using retrograde regulation of axonal actin dynamics to mobilize and recruit presynaptic SV resources.
Collapse
Affiliation(s)
- Nicolas Chenouard
- NYU Neuroscience Institute and Department of Neuroscience and Physiology, NYU Langone Medical Center, New York, NY, 10016, USA.,Univ. Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, F-33000, Bordeaux, France
| | - Feng Xuan
- NYU Neuroscience Institute and Department of Neuroscience and Physiology, NYU Langone Medical Center, New York, NY, 10016, USA.,Interdepartmental Neuroscience Program, Northwestern University, Evanston, IL, 60208, USA
| | - Richard W Tsien
- NYU Neuroscience Institute and Department of Neuroscience and Physiology, NYU Langone Medical Center, New York, NY, 10016, USA. .,Center for Neural Science, New York University, New York, NY, 10003, USA.
| |
Collapse
|
14
|
Reshetniak S, Ußling J, Perego E, Rammner B, Schikorski T, Fornasiero EF, Truckenbrodt S, Köster S, Rizzoli SO. A comparative analysis of the mobility of 45 proteins in the synaptic bouton. EMBO J 2020; 39:e104596. [PMID: 32627850 PMCID: PMC7429486 DOI: 10.15252/embj.2020104596] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 05/20/2020] [Accepted: 05/29/2020] [Indexed: 02/01/2023] Open
Abstract
Many proteins involved in synaptic transmission are well known, and their features, as their abundance or spatial distribution, have been analyzed in systematic studies. This has not been the case, however, for their mobility. To solve this, we analyzed the motion of 45 GFP-tagged synaptic proteins expressed in cultured hippocampal neurons, using fluorescence recovery after photobleaching, particle tracking, and modeling. We compared synaptic vesicle proteins, endo- and exocytosis cofactors, cytoskeleton components, and trafficking proteins. We found that movement was influenced by the protein association with synaptic vesicles, especially for membrane proteins. Surprisingly, protein mobility also correlated significantly with parameters as the protein lifetimes, or the nucleotide composition of their mRNAs. We then analyzed protein movement thoroughly, taking into account the spatial characteristics of the system. This resulted in a first visualization of overall protein motion in the synapse, which should enable future modeling studies of synaptic physiology.
Collapse
Affiliation(s)
- Sofiia Reshetniak
- Institute for Neuro‐ and Sensory Physiology and Biostructural Imaging of Neurodegeneration (BIN) CenterUniversity Medical Center GöttingenGöttingenGermany
- International Max Planck Research School for Molecular BiologyGöttingenGermany
| | - Jan‐Eike Ußling
- Institute for Neuro‐ and Sensory Physiology and Biostructural Imaging of Neurodegeneration (BIN) CenterUniversity Medical Center GöttingenGöttingenGermany
| | - Eleonora Perego
- Institute for X‐Ray PhysicsUniversity of GöttingenGöttingenGermany
| | - Burkhard Rammner
- Institute for Neuro‐ and Sensory Physiology and Biostructural Imaging of Neurodegeneration (BIN) CenterUniversity Medical Center GöttingenGöttingenGermany
| | - Thomas Schikorski
- Department of NeuroscienceUniversidad Central del CaribeBayamonPRUSA
| | - Eugenio F Fornasiero
- Institute for Neuro‐ and Sensory Physiology and Biostructural Imaging of Neurodegeneration (BIN) CenterUniversity Medical Center GöttingenGöttingenGermany
| | - Sven Truckenbrodt
- Institute for Neuro‐ and Sensory Physiology and Biostructural Imaging of Neurodegeneration (BIN) CenterUniversity Medical Center GöttingenGöttingenGermany
- International Max Planck Research School for Molecular BiologyGöttingenGermany
| | - Sarah Köster
- Institute for X‐Ray PhysicsUniversity of GöttingenGöttingenGermany
- Cluster of Excellence “Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells” (MBExC)University of GöttingenGöttingenGermany
| | - Silvio O Rizzoli
- Institute for Neuro‐ and Sensory Physiology and Biostructural Imaging of Neurodegeneration (BIN) CenterUniversity Medical Center GöttingenGöttingenGermany
- Cluster of Excellence “Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells” (MBExC)University of GöttingenGöttingenGermany
| |
Collapse
|
15
|
Pietrancosta N, Djibo M, Daumas S, El Mestikawy S, Erickson JD. Molecular, Structural, Functional, and Pharmacological Sites for Vesicular Glutamate Transporter Regulation. Mol Neurobiol 2020; 57:3118-3142. [PMID: 32474835 PMCID: PMC7261050 DOI: 10.1007/s12035-020-01912-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 03/30/2020] [Indexed: 12/11/2022]
Abstract
Vesicular glutamate transporters (VGLUTs) control quantal size of glutamatergic transmission and have been the center of numerous studies over the past two decades. VGLUTs contain two independent transport modes that facilitate glutamate packaging into synaptic vesicles and phosphate (Pi) ion transport into the synaptic terminal. While a transmembrane proton electrical gradient established by a vacuolar-type ATPase powers vesicular glutamate transport, recent studies indicate that binding sites and flux properties for chloride, potassium, and protons within VGLUTs themselves regulate VGLUT activity as well. These intrinsic ionic binding and flux properties of VGLUTs can therefore be modulated by neurophysiological conditions to affect levels of glutamate available for release from synapses. Despite their extraordinary importance, specific and high-affinity pharmacological compounds that interact with these sites and regulate VGLUT function, distinguish between the various modes of transport, and the different isoforms themselves, are lacking. In this review, we provide an overview of the physiologic sites for VGLUT regulation that could modulate glutamate release in an over-active synapse or in a disease state.
Collapse
Affiliation(s)
- Nicolas Pietrancosta
- Neuroscience Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS) INSERM, CNRS, Sorbonne Université, Paris, France. .,Laboratoire des Biomolécules, Sorbonne Université, CNRS, ENS, LBM, 75005, Paris, France.
| | - Mahamadou Djibo
- Sorbonne Paris Cité, Université Paris Descartes, LCBPT, UMR 8601, 75006, Paris, France
| | - Stephanie Daumas
- Neuroscience Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS) INSERM, CNRS, Sorbonne Université, Paris, France
| | - Salah El Mestikawy
- Neuroscience Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS) INSERM, CNRS, Sorbonne Université, Paris, France. .,Douglas Hospital Research Center, Department of Psychiatry, McGill University, 6875 boulevard Lasalle, Verdun, Montreal, QC, Canada.
| | - Jeffrey D Erickson
- Neuroscience Center, Louisiana State University, New Orleans, LA, 70112, USA. .,Department of Pharmacology, Louisiana State University, New Orleans, LA, 70112, USA.
| |
Collapse
|
16
|
Hafner AS, Donlin-Asp PG, Leitch B, Herzog E, Schuman EM. Local protein synthesis is a ubiquitous feature of neuronal pre- and postsynaptic compartments. Science 2019; 364:364/6441/eaau3644. [PMID: 31097639 DOI: 10.1126/science.aau3644] [Citation(s) in RCA: 224] [Impact Index Per Article: 44.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2018] [Revised: 01/16/2019] [Accepted: 04/02/2019] [Indexed: 12/11/2022]
Abstract
There is ample evidence for localization of messenger RNAs (mRNAs) and protein synthesis in neuronal dendrites; however, demonstrations of these processes in presynaptic terminals are limited. We used expansion microscopy to resolve pre- and postsynaptic compartments in rodent neurons. Most presynaptic terminals in the hippocampus and forebrain contained mRNA and ribosomes. We sorted fluorescently labeled mouse brain synaptosomes and then sequenced hundreds of mRNA species present within excitatory boutons. After brief metabolic labeling, >30% of all presynaptic terminals exhibited a signal, providing evidence for ongoing protein synthesis. We tested different classic plasticity paradigms and observed distinct patterns of rapid pre- and/or postsynaptic translation. Thus, presynaptic terminals are translationally competent, and local protein synthesis is differentially recruited to drive compartment-specific phenotypes that underlie different forms of plasticity.
Collapse
Affiliation(s)
| | | | - Beulah Leitch
- Department of Anatomy, School of Biomedical Sciences and the Brain Health Research Centre, University of Otago, Dunedin, New Zealand
| | - Etienne Herzog
- Interdisciplinary Institute for Neuroscience, University of Bordeaux, UMR 5297, F-33000, Bordeaux, France.,Interdisciplinary Institute for Neuroscience, CNRS, UMR 5297, F-33000, Bordeaux, France
| | - Erin M Schuman
- Max Planck Institute for Brain Research, Frankfurt, Germany.
| |
Collapse
|
17
|
Peters F, Salihoglu H, Pratsch K, Herzog E, Pigoni M, Sgobio C, Lichtenthaler SF, Neumann U, Herms J. Tau deletion reduces plaque-associated BACE1 accumulation and decelerates plaque formation in a mouse model of Alzheimer's disease. EMBO J 2019; 38:e102345. [PMID: 31701556 PMCID: PMC6885735 DOI: 10.15252/embj.2019102345] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 09/29/2019] [Accepted: 10/08/2019] [Indexed: 01/24/2023] Open
Abstract
In Alzheimer's disease, BACE1 protease initiates the amyloidogenic processing of amyloid precursor protein (APP) that eventually results in synthesis of β-amyloid (Aβ) peptide. Aβ deposition in turn causes accumulation of BACE1 in plaque-associated dystrophic neurites, thereby potentiating progressive Aβ deposition once initiated. Since systemic pharmacological BACE inhibition causes adverse effects in humans, it is important to identify strategies that specifically normalize overt BACE1 activity around plaques. The microtubule-associated protein tau regulates axonal transport of proteins, and tau deletion rescues Aβ-induced transport deficits in vitro. In the current study, long-term in vivo two-photon microscopy and immunohistochemistry were performed in tau-deficient APPPS1 mice. Tau deletion reduced plaque-associated axonal pathology and BACE1 accumulation without affecting physiological BACE1 expression distant from plaques. Thereby, tau deletion effectively decelerated formation of new plaques and reduced plaque compactness. The data revealed that tau reinforces Aβ deposition, presumably by contributing to accumulation of BACE1 in plaque-associated dystrophies. Targeting tau-dependent mechanisms could become a suitable strategy to specifically reduce overt BACE1 activity around plaques, thereby avoiding adverse effects of systemic BACE inhibition.
Collapse
Affiliation(s)
- Finn Peters
- German Center for Neurodegenerative Diseases (DZNE)MunichGermany
- Munich Cluster of Systems Neurology (SyNergy)MunichGermany
| | - Hazal Salihoglu
- German Center for Neurodegenerative Diseases (DZNE)MunichGermany
- Munich Cluster of Systems Neurology (SyNergy)MunichGermany
| | - Katrin Pratsch
- German Center for Neurodegenerative Diseases (DZNE)MunichGermany
| | - Etienne Herzog
- IINS, UMR 5297Université BordeauxBordeauxFrance
- CNRS, IINS, UMR 5297BordeauxFrance
| | - Martina Pigoni
- German Center for Neurodegenerative Diseases (DZNE)MunichGermany
- Munich Cluster of Systems Neurology (SyNergy)MunichGermany
| | - Carmelo Sgobio
- German Center for Neurodegenerative Diseases (DZNE)MunichGermany
| | - Stefan F Lichtenthaler
- German Center for Neurodegenerative Diseases (DZNE)MunichGermany
- Munich Cluster of Systems Neurology (SyNergy)MunichGermany
- NeuroproteomicsSchool of MedicineKlinikum rechts der Isar and Institute for Advanced StudyTechnical University of MunichMunichGermany
| | - Ulf Neumann
- NeuroscienceNovartis Institutes for BioMedical Research (NIBR)BaselSwitzerland
| | - Jochen Herms
- German Center for Neurodegenerative Diseases (DZNE)MunichGermany
- Munich Cluster of Systems Neurology (SyNergy)MunichGermany
- Center for Neuropathology and Prion ResearchLudwig‐Maximilians UniversityMunichGermany
| |
Collapse
|
18
|
Early defects in translation elongation factor 1α levels at excitatory synapses in α-synucleinopathy. Acta Neuropathol 2019; 138:971-986. [PMID: 31451907 DOI: 10.1007/s00401-019-02063-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 08/14/2019] [Accepted: 08/15/2019] [Indexed: 01/08/2023]
Abstract
Cognitive decline and dementia in neurodegenerative diseases are associated with synapse dysfunction and loss, which may precede neuron loss by several years. While misfolded and aggregated α-synuclein is recognized in the disease progression of synucleinopathies, the nature of glutamatergic synapse dysfunction and loss remains incompletely understood. Using fluorescence-activated synaptosome sorting (FASS), we enriched excitatory glutamatergic synaptosomes from mice overexpressing human alpha-synuclein (h-αS) and wild-type littermates to unprecedented purity. Subsequent label-free proteomic quantification revealed a set of proteins differentially expressed upon human alpha-synuclein overexpression. These include overrepresented proteins involved in the synaptic vesicle cycle, ER-Golgi trafficking, metabolism and cytoskeleton. Unexpectedly, we found and validated a steep reduction of eukaryotic translation elongation factor 1 alpha (eEF1A1) levels in excitatory synapses at early stages of h-αS mouse model pathology. While eEF1A1 reduction correlated with the loss of postsynapses, its immunoreactivity was found on both sides of excitatory synapses. Moreover, we observed a reduction in eEF1A1 immunoreactivity in the cingulate gyrus neuropil of patients with Lewy body disease along with a reduction in PSD95 levels. Altogether, our results suggest a link between structural impairments underlying cognitive decline in neurodegenerative disorders and local synaptic defects. eEF1A1 may therefore represent a limiting factor to synapse maintenance.
Collapse
|
19
|
Zhang XM, François U, Silm K, Angelo MF, Fernandez-Busch MV, Maged M, Martin C, Bernard V, Cordelières FP, Deshors M, Pons S, Maskos U, Bemelmans AP, Wojcik SM, El Mestikawy S, Humeau Y, Herzog E. A proline-rich motif on VGLUT1 reduces synaptic vesicle super-pool and spontaneous release frequency. eLife 2019; 8:50401. [PMID: 31663854 PMCID: PMC6861006 DOI: 10.7554/elife.50401] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 10/27/2019] [Indexed: 12/29/2022] Open
Abstract
Glutamate secretion at excitatory synapses is tightly regulated to allow for the precise tuning of synaptic strength. Vesicular Glutamate Transporters (VGLUT) accumulate glutamate into synaptic vesicles (SV) and thereby regulate quantal size. Further, the number of release sites and the release probability of SVs maybe regulated by the organization of active-zone proteins and SV clusters. In the present work, we uncover a mechanism mediating an increased SV clustering through the interaction of VGLUT1 second proline-rich domain, endophilinA1 and intersectin1. This strengthening of SV clusters results in a combined reduction of axonal SV super-pool size and miniature excitatory events frequency. Our findings support a model in which clustered vesicles are held together through multiple weak interactions between Src homology three and proline-rich domains of synaptic proteins. In mammals, VGLUT1 gained a proline-rich sequence that recruits endophilinA1 and turns the transporter into a regulator of SV organization and spontaneous release.
Collapse
Affiliation(s)
- Xiao Min Zhang
- Interdisciplinary Institute for Neuroscience, Université de Bordeaux, Bordeaux, France.,Interdisciplinary Institute for Neuroscience CNRS UMR 5297, Bordeaux, France.,Department of Molecular Neurobiology, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Urielle François
- Interdisciplinary Institute for Neuroscience, Université de Bordeaux, Bordeaux, France.,Interdisciplinary Institute for Neuroscience CNRS UMR 5297, Bordeaux, France
| | - Kätlin Silm
- Neuroscience Paris Seine NPS, Université Pierre et Marie Curie INSERM U1130 CNRS UMR8246, Paris, France
| | - Maria Florencia Angelo
- Interdisciplinary Institute for Neuroscience, Université de Bordeaux, Bordeaux, France.,Interdisciplinary Institute for Neuroscience CNRS UMR 5297, Bordeaux, France
| | - Maria Victoria Fernandez-Busch
- Interdisciplinary Institute for Neuroscience, Université de Bordeaux, Bordeaux, France.,Interdisciplinary Institute for Neuroscience CNRS UMR 5297, Bordeaux, France
| | - Mona Maged
- Interdisciplinary Institute for Neuroscience, Université de Bordeaux, Bordeaux, France.,Interdisciplinary Institute for Neuroscience CNRS UMR 5297, Bordeaux, France
| | - Christelle Martin
- Interdisciplinary Institute for Neuroscience, Université de Bordeaux, Bordeaux, France.,Interdisciplinary Institute for Neuroscience CNRS UMR 5297, Bordeaux, France
| | - Véronique Bernard
- Neuroscience Paris Seine NPS, Université Pierre et Marie Curie INSERM U1130 CNRS UMR8246, Paris, France
| | - Fabrice P Cordelières
- Bordeaux Imaging Center, Université de Bordeaux, CNRS UMS 3420, INSERM US4, Bordeaux, France
| | - Melissa Deshors
- Interdisciplinary Institute for Neuroscience, Université de Bordeaux, Bordeaux, France.,Interdisciplinary Institute for Neuroscience CNRS UMR 5297, Bordeaux, France
| | - Stéphanie Pons
- Institut Pasteur, CNRS UMR 3571, Unité NISC, Paris, France
| | - Uwe Maskos
- Institut Pasteur, CNRS UMR 3571, Unité NISC, Paris, France
| | - Alexis Pierre Bemelmans
- Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), Direction de laRecherche Fondamentale (DRF), Institut de Biologie François Jacob (IBFJ), MolecularImaging Research Center (MIRCen), Fontenay-aux-Roses, France
| | - Sonja M Wojcik
- Department of Molecular Neurobiology, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Salah El Mestikawy
- Neuroscience Paris Seine NPS, Université Pierre et Marie Curie INSERM U1130 CNRS UMR8246, Paris, France.,Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montreal, Canada
| | - Yann Humeau
- Interdisciplinary Institute for Neuroscience, Université de Bordeaux, Bordeaux, France.,Interdisciplinary Institute for Neuroscience CNRS UMR 5297, Bordeaux, France
| | - Etienne Herzog
- Interdisciplinary Institute for Neuroscience, Université de Bordeaux, Bordeaux, France.,Interdisciplinary Institute for Neuroscience CNRS UMR 5297, Bordeaux, France
| |
Collapse
|
20
|
The light-sensitive dimerizer zapalog reveals distinct modes of immobilization for axonal mitochondria. Nat Cell Biol 2019; 21:768-777. [PMID: 31061466 PMCID: PMC6662610 DOI: 10.1038/s41556-019-0317-2] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 03/25/2019] [Indexed: 01/18/2023]
Abstract
Controlling cellular processes with light can help elucidate their underlying mechanisms. Here we present zapalog, a small-molecule dimerizer that undergoes photolysis when exposed to blue light. Zapalog dimerizes any two proteins tagged with the FKBP and DHFR domains until exposure to light causes its photolysis. Dimerization can be repeatedly restored with uncleaved zapalog. We implement this method to investigate mitochondrial motility and positioning in cultured neurons. Using zapalog, we tether mitochondria to constitutively active kinesin motors, forcing them down the axon towards microtubule (+) ends until their instantaneous release via blue light, which results in full restoration of their endogenous motility. We find that one-third of stationary mitochondria cannot be pulled away from their position and that these firmly anchored mitochondria preferentially localize to VGLUT1-positive presynapses. Furthermore, inhibition of actin polymerization with latrunculin A reduces this firmly anchored pool. On release from exogenous motors, mitochondria are preferentially recaptured at presynapses.
Collapse
|
21
|
Multiple roles of the actin and microtubule-regulating formins in the developing brain. Neurosci Res 2019; 138:59-69. [DOI: 10.1016/j.neures.2018.09.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 08/22/2018] [Accepted: 08/23/2018] [Indexed: 01/08/2023]
|
22
|
McKenzie C, Spanova M, Johnson A, Kainrath S, Zheden V, Sitte HH, Janovjak H. Isolation of synaptic vesicles from genetically engineered cultured neurons. J Neurosci Methods 2018; 312:114-121. [PMID: 30496761 DOI: 10.1016/j.jneumeth.2018.11.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2018] [Revised: 11/19/2018] [Accepted: 11/20/2018] [Indexed: 12/18/2022]
Abstract
BACKGROUND Synaptic vesicles (SVs) are an integral part of the neurotransmission machinery, and isolation of SVs from their host neuron is necessary to reveal their most fundamental biochemical and functional properties in in vitro assays. Isolated SVs from neurons that have been genetically engineered, e.g. to introduce genetically encoded indicators, are not readily available but would permit new insights into SV structure and function. Furthermore, it is unclear if cultured neurons can provide sufficient starting material for SV isolation procedures. NEW METHOD Here, we demonstrate an efficient ex vivo procedure to obtain functional SVs from cultured rat cortical neurons after genetic engineering with a lentivirus. RESULTS We show that ∼108 plated cortical neurons allow isolation of suitable SV amounts for functional analysis and imaging. We found that SVs isolated from cultured neurons have neurotransmitter uptake comparable to that of SVs isolated from intact cortex. Using total internal reflection fluorescence (TIRF) microscopy, we visualized an exogenous SV-targeted marker protein and demonstrated the high efficiency of SV modification. COMPARISON WITH EXISTING METHODS Obtaining SVs from genetically engineered neurons currently generally requires the availability of transgenic animals, which is constrained by technical (e.g. cost and time) and biological (e.g. developmental defects and lethality) limitations. CONCLUSIONS These results demonstrate the modification and isolation of functional SVs using cultured neurons and viral transduction. The ability to readily obtain SVs from genetically engineered neurons will permit linking in situ studies to in vitro experiments in a variety of genetic contexts.
Collapse
Affiliation(s)
- Catherine McKenzie
- Institute of Science and Technology Austria (IST Austria), Am Campus 1, 3400 Klosterneuburg, Austria
| | - Miroslava Spanova
- Institute of Science and Technology Austria (IST Austria), Am Campus 1, 3400 Klosterneuburg, Austria
| | - Alexander Johnson
- Institute of Science and Technology Austria (IST Austria), Am Campus 1, 3400 Klosterneuburg, Austria
| | - Stephanie Kainrath
- Institute of Science and Technology Austria (IST Austria), Am Campus 1, 3400 Klosterneuburg, Austria
| | - Vanessa Zheden
- Institute of Science and Technology Austria (IST Austria), Am Campus 1, 3400 Klosterneuburg, Austria
| | - Harald H Sitte
- Medical University of Vienna, Center for Physiology and Pharmacology, Institute of Pharmacology, Waehringerstrasse 13A, 1090, Vienna, Austria
| | - Harald Janovjak
- Institute of Science and Technology Austria (IST Austria), Am Campus 1, 3400 Klosterneuburg, Austria; Australian Regenerative Medicine Institute (ARMI), Faculty of Medicine, Nursing and Health Sciences, Monash University, 15 Innovation Walk, Clayton, Melbourne, VIC 3800, Australia; European Molecular Biology Laboratory Australia (EMBL Australia), Monash University, 15 Innovation Walk, Clayton, Melbourne, VIC 3800, Australia.
| |
Collapse
|
23
|
Presynaptic Biogenesis Requires Axonal Transport of Lysosome-Related Vesicles. Neuron 2018; 99:1216-1232.e7. [DOI: 10.1016/j.neuron.2018.08.004] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 05/18/2018] [Accepted: 08/02/2018] [Indexed: 01/05/2023]
|
24
|
Varando G, Benavides-Piccione R, Muñoz A, Kastanauskaite A, Bielza C, Larrañaga P, DeFelipe J. MultiMap: A Tool to Automatically Extract and Analyse Spatial Microscopic Data From Large Stacks of Confocal Microscopy Images. Front Neuroanat 2018; 12:37. [PMID: 29875639 PMCID: PMC5974206 DOI: 10.3389/fnana.2018.00037] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 04/24/2018] [Indexed: 11/13/2022] Open
Abstract
The development of 3D visualization and reconstruction methods to analyse microscopic structures at different levels of resolutions is of great importance to define brain microorganization and connectivity. MultiMap is a new tool that allows the visualization, 3D segmentation and quantification of fluorescent structures selectively in the neuropil from large stacks of confocal microscopy images. The major contribution of this tool is the posibility to easily navigate and create regions of interest of any shape and size within a large brain area that will be automatically 3D segmented and quantified to determine the density of puncta in the neuropil. As a proof of concept, we focused on the analysis of glutamatergic and GABAergic presynaptic axon terminals in the mouse hippocampal region to demonstrate its use as a tool to provide putative excitatory and inhibitory synaptic maps. The segmentation and quantification method has been validated over expert labeled images of the mouse hippocampus and over two benchmark datasets, obtaining comparable results to the expert detections.
Collapse
Affiliation(s)
- Gherardo Varando
- Computational Intelligence Group, Department of Artificial Intelligence, Universidad Politécnica de Madrid, Madrid, Spain
| | - Ruth Benavides-Piccione
- Departamento de Neurobiología Funcional y de Sistemas, Instituto Cajal (CSIC), Madrid, Spain.,Laboratorio Cajal de Circuitos Corticales, Centro de Tecnología Biomédica, Universidad Politécnica de Madrid, Madrid, Spain
| | - Alberto Muñoz
- Departamento de Neurobiología Funcional y de Sistemas, Instituto Cajal (CSIC), Madrid, Spain.,Laboratorio Cajal de Circuitos Corticales, Centro de Tecnología Biomédica, Universidad Politécnica de Madrid, Madrid, Spain.,Departamento de Biología Celular, Universidad Complutense, Madrid, Spain
| | - Asta Kastanauskaite
- Departamento de Neurobiología Funcional y de Sistemas, Instituto Cajal (CSIC), Madrid, Spain.,Laboratorio Cajal de Circuitos Corticales, Centro de Tecnología Biomédica, Universidad Politécnica de Madrid, Madrid, Spain
| | - Concha Bielza
- Computational Intelligence Group, Department of Artificial Intelligence, Universidad Politécnica de Madrid, Madrid, Spain
| | - Pedro Larrañaga
- Computational Intelligence Group, Department of Artificial Intelligence, Universidad Politécnica de Madrid, Madrid, Spain
| | - Javier DeFelipe
- Departamento de Neurobiología Funcional y de Sistemas, Instituto Cajal (CSIC), Madrid, Spain.,Laboratorio Cajal de Circuitos Corticales, Centro de Tecnología Biomédica, Universidad Politécnica de Madrid, Madrid, Spain
| |
Collapse
|
25
|
Cavaccini A, Gritti M, Giorgi A, Locarno A, Heck N, Migliarini S, Bertero A, Mereu M, Margiani G, Trusel M, Catelani T, Marotta R, De Luca MA, Caboche J, Gozzi A, Pasqualetti M, Tonini R. Serotonergic Signaling Controls Input-Specific Synaptic Plasticity at Striatal Circuits. Neuron 2018; 98:801-816.e7. [DOI: 10.1016/j.neuron.2018.04.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Revised: 02/15/2018] [Accepted: 04/05/2018] [Indexed: 10/17/2022]
|
26
|
Peters F, Salihoglu H, Rodrigues E, Herzog E, Blume T, Filser S, Dorostkar M, Shimshek DR, Brose N, Neumann U, Herms J. BACE1 inhibition more effectively suppresses initiation than progression of β-amyloid pathology. Acta Neuropathol 2018; 135:695-710. [PMID: 29327084 PMCID: PMC5904228 DOI: 10.1007/s00401-017-1804-9] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2017] [Revised: 12/28/2017] [Accepted: 12/29/2017] [Indexed: 01/04/2023]
Abstract
BACE1 is the rate-limiting protease in the production of synaptotoxic β-amyloid (Aβ) species and hence one of the prime drug targets for potential therapy of Alzheimer's disease (AD). However, so far pharmacological BACE1 inhibition failed to rescue the cognitive decline in mild-to-moderate AD patients, which indicates that treatment at the symptomatic stage might be too late. In the current study, chronic in vivo two-photon microscopy was performed in a transgenic AD model to monitor the impact of pharmacological BACE1 inhibition on early β-amyloid pathology. The longitudinal approach allowed to assess the kinetics of individual plaques and associated presynaptic pathology, before and throughout treatment. BACE1 inhibition could not halt but slow down progressive β-amyloid deposition and associated synaptic pathology. Notably, the data revealed that the initial process of plaque formation, rather than the subsequent phase of gradual plaque growth, is most sensitive to BACE1 inhibition. This finding of particular susceptibility of plaque formation has profound implications to achieve optimal therapeutic efficacy for the prospective treatment of AD.
Collapse
Affiliation(s)
- Finn Peters
- German Center for Neurodegenerative Diseases (DZNE), Feodor-Lynen Str. 17, 81377, Munich, Germany
- Munich Cluster of Systems Neurology (SyNergy), Munich, Germany
| | - Hazal Salihoglu
- German Center for Neurodegenerative Diseases (DZNE), Feodor-Lynen Str. 17, 81377, Munich, Germany
| | - Eva Rodrigues
- German Center for Neurodegenerative Diseases (DZNE), Feodor-Lynen Str. 17, 81377, Munich, Germany
| | - Etienne Herzog
- Université Bordeaux, IINS, UMR 5297, 33000, Bordeaux, France
- CNRS, IINS, UMR 5297, 33000, Bordeaux, France
| | - Tanja Blume
- German Center for Neurodegenerative Diseases (DZNE), Feodor-Lynen Str. 17, 81377, Munich, Germany
- Munich Cluster of Systems Neurology (SyNergy), Munich, Germany
| | - Severin Filser
- German Center for Neurodegenerative Diseases (DZNE), Feodor-Lynen Str. 17, 81377, Munich, Germany
- Munich Cluster of Systems Neurology (SyNergy), Munich, Germany
| | - Mario Dorostkar
- German Center for Neurodegenerative Diseases (DZNE), Feodor-Lynen Str. 17, 81377, Munich, Germany
- Center for Neuropathology and Prion Research, Ludwig-Maximilians University, Munich, Germany
| | - Derya R Shimshek
- Neuroscience, Novartis Institutes for BioMedical Research (NIBR), Basel, Switzerland
| | - Nils Brose
- Department of Molecular Neurobiology, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Ulf Neumann
- Neuroscience, Novartis Institutes for BioMedical Research (NIBR), Basel, Switzerland
| | - Jochen Herms
- German Center for Neurodegenerative Diseases (DZNE), Feodor-Lynen Str. 17, 81377, Munich, Germany.
- Munich Cluster of Systems Neurology (SyNergy), Munich, Germany.
- Center for Neuropathology and Prion Research, Ludwig-Maximilians University, Munich, Germany.
| |
Collapse
|
27
|
Synaptic Tenacity or Lack Thereof: Spontaneous Remodeling of Synapses. Trends Neurosci 2018; 41:89-99. [DOI: 10.1016/j.tins.2017.12.003] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 11/22/2017] [Accepted: 12/04/2017] [Indexed: 11/18/2022]
|
28
|
Moderate decline in select synaptic markers in the prefrontal cortex (BA9) of patients with Alzheimer's disease at various cognitive stages. Sci Rep 2018; 8:938. [PMID: 29343737 PMCID: PMC5772053 DOI: 10.1038/s41598-018-19154-y] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 12/22/2017] [Indexed: 01/28/2023] Open
Abstract
Synaptic loss, plaques and neurofibrillary tangles are viewed as hallmarks of Alzheimer's disease (AD). This study investigated synaptic markers in neocortical Brodmann area 9 (BA9) samples from 171 subjects with and without AD at different levels of cognitive impairment. The expression levels of vesicular glutamate transporters (VGLUT1&2), glutamate uptake site (EAAT2), post-synaptic density protein of 95 kD (PSD95), vesicular GABA/glycine transporter (VIAAT), somatostatin (som), synaptophysin and choline acetyl transferase (ChAT) were evaluated. VGLUT2 and EAAT2 were unaffected by dementia. The VGLUT1, PSD95, VIAAT, som, ChAT and synaptophysin expression levels significantly decreased as dementia progressed. The maximal decrease varied between 12% (synaptophysin) and 42% (som). VGLUT1 was more strongly correlated with dementia than all of the other markers (polyserial correlation = -0.41). Principal component analysis using these markers was unable to differentiate the CDR groups from one another. Therefore, the status of the major synaptic markers in BA9 does not seem to be linked to the cognitive status of AD patients. The findings of this study suggest that the loss of synaptic markers in BA9 is a late event that is only weakly related to AD dementia.
Collapse
|
29
|
Dos Santos M, Salery M, Forget B, Garcia Perez MA, Betuing S, Boudier T, Vanhoutte P, Caboche J, Heck N. Rapid Synaptogenesis in the Nucleus Accumbens Is Induced by a Single Cocaine Administration and Stabilized by Mitogen-Activated Protein Kinase Interacting Kinase-1 Activity. Biol Psychiatry 2017; 82:806-818. [PMID: 28545678 DOI: 10.1016/j.biopsych.2017.03.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 03/10/2017] [Accepted: 03/14/2017] [Indexed: 12/21/2022]
Abstract
BACKGROUND Repeated cocaine exposure produces new spine formation in striatal projection neurons (SPNs) of the nucleus accumbens. However, an acute exposure to cocaine can trigger long-lasting synaptic plasticity in SPNs leading to behavioral alterations. This raises the intriguing question as to whether a single administration of cocaine could enduringly modify striatal connectivity. METHODS A three-dimensional morphometric analysis of presynaptic glutamatergic boutons and dendritic spines was performed on SPNs 1 hour and 1 week after a single cocaine administration. Time-lapse two-photon microscopy in adult slices was used to determine the precise molecular-events sequence responsible for the rapid spine formation. RESULTS A single injection triggered a rapid synaptogenesis and persistent increase in glutamatergic connectivity in SPNs from the shell part of the nucleus accumbens, specifically. Synapse formation occurred through clustered growth of active spines contacting pre-existing axonal boutons. Spine growth required extracellular signal-regulated kinase activation, while spine stabilization involved transcription-independent protein synthesis driven by mitogen-activated protein kinase interacting kinase-1, downstream from extracellular signal-regulated kinase. The maintenance of new spines driven by mitogen-activated protein kinase interacting kinase-1 was essential for long-term connectivity changes induced by cocaine in vivo. CONCLUSIONS Our study originally demonstrates that a single administration of cocaine is able to induce stable synaptic rewiring in the nucleus accumbens, which will likely influence responses to subsequent drug exposure. It also unravels a new functional role for cocaine-induced extracellular signal-regulated kinase pathway independently of nuclear targets. Finally, it reveals that mitogen-activated protein kinase interacting kinase-1 has a pivotal role in cocaine-induced connectivity.
Collapse
Affiliation(s)
- Marc Dos Santos
- Neurosciences Paris Seine, Institut de Biologie Paris Seine, University Pierre and Marie Curie University of Paris 06, Sorbonne Universités, Centre National pour la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Paris, France
| | - Marine Salery
- Neurosciences Paris Seine, Institut de Biologie Paris Seine, University Pierre and Marie Curie University of Paris 06, Sorbonne Universités, Centre National pour la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Paris, France
| | - Benoit Forget
- Neurosciences Paris Seine, Institut de Biologie Paris Seine, University Pierre and Marie Curie University of Paris 06, Sorbonne Universités, Centre National pour la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Paris, France
| | - Maria Alexandra Garcia Perez
- Neurosciences Paris Seine, Institut de Biologie Paris Seine, University Pierre and Marie Curie University of Paris 06, Sorbonne Universités, Centre National pour la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Paris, France
| | - Sandrine Betuing
- Neurosciences Paris Seine, Institut de Biologie Paris Seine, University Pierre and Marie Curie University of Paris 06, Sorbonne Universités, Centre National pour la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Paris, France
| | - Thomas Boudier
- Neurosciences Paris Seine, Institut de Biologie Paris Seine, University Pierre and Marie Curie University of Paris 06, Sorbonne Universités, Centre National pour la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Paris, France; Bioinformatics Institute, Agency for Science, Technology, and Research, Singapore
| | - Peter Vanhoutte
- Neurosciences Paris Seine, Institut de Biologie Paris Seine, University Pierre and Marie Curie University of Paris 06, Sorbonne Universités, Centre National pour la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Paris, France
| | - Jocelyne Caboche
- Neurosciences Paris Seine, Institut de Biologie Paris Seine, University Pierre and Marie Curie University of Paris 06, Sorbonne Universités, Centre National pour la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Paris, France.
| | - Nicolas Heck
- Neurosciences Paris Seine, Institut de Biologie Paris Seine, University Pierre and Marie Curie University of Paris 06, Sorbonne Universités, Centre National pour la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Paris, France
| |
Collapse
|
30
|
Fattorini G, Ciriachi C, Conti F. Few, Activity-Dependent, and Ubiquitous VGLUT1/VGAT Terminals in Rat and Mouse Brain. Front Cell Neurosci 2017; 11:229. [PMID: 28848395 PMCID: PMC5550726 DOI: 10.3389/fncel.2017.00229] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 07/20/2017] [Indexed: 11/13/2022] Open
Abstract
In the neocortex of adult rats VGLUT1 and VGAT co-localize in axon terminals which form both symmetric and asymmetric synapses. They are expressed in the same synaptic vesicles which participate in the exo-endocytotic cycle. Virtually nothing, however, is known on whether VGLUT1/VGAT co-localization occurs in other brain regions. We therefore mapped the distribution of terminals co-expressing VGLUT1/VGAT in the striatum, hippocampus, thalamus, and cerebellar and cerebral cortices of rats and mice. Confocal microscopy analysis revealed that, in both rat and mouse brain, VGLUT1/VGAT+ terminals were present in all brain regions studied, and that their percentage was low and comparable in both species. These results provide the first demonstration that co-expression of VGLUT1 and VGAT is a widespread phenomenon. Since VGLUT1/VGAT+ axon terminals are regulated in an activity-dependent manner and co-release glutamate and GABA, we hypothesize that, though not numerous, they can contribute to regulating excitation/inhibition balance in physiological conditions, thereby playing a role in several neurological and psychiatric diseases.
Collapse
Affiliation(s)
- Giorgia Fattorini
- Department of Experimental and Clinical Medicine, Section of Neuroscience and Cell Biology, Università Politecnica delle MarcheAncona, Italy.,Center for Neurobiology of Aging, Istituto Nazionale di Riposo e Cura per Anziani - Istituto di Ricovero e Cura a Carattere ScientificoAncona, Italy
| | - Chiara Ciriachi
- Department of Experimental and Clinical Medicine, Section of Neuroscience and Cell Biology, Università Politecnica delle MarcheAncona, Italy
| | - Fiorenzo Conti
- Department of Experimental and Clinical Medicine, Section of Neuroscience and Cell Biology, Università Politecnica delle MarcheAncona, Italy.,Center for Neurobiology of Aging, Istituto Nazionale di Riposo e Cura per Anziani - Istituto di Ricovero e Cura a Carattere ScientificoAncona, Italy.,Fondazione di Medicina Molecolare, Università Politecnica delle MarcheAncona, Italy
| |
Collapse
|
31
|
Geerts CJ, Mancini R, Chen N, Koopmans FTW, Li KW, Smit AB, van Weering JRT, Verhage M, Groffen AJA. Tomosyn associates with secretory vesicles in neurons through its N- and C-terminal domains. PLoS One 2017; 12:e0180912. [PMID: 28746398 PMCID: PMC5529015 DOI: 10.1371/journal.pone.0180912] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 06/22/2017] [Indexed: 02/03/2023] Open
Abstract
The secretory pathway in neurons requires efficient targeting of cargos and regulatory proteins to their release sites. Tomosyn contributes to synapse function by regulating synaptic vesicle (SV) and dense-core vesicle (DCV) secretion. While there is large support for the presynaptic accumulation of tomosyn in fixed preparations, alternative subcellular locations have been suggested. Here we studied the dynamic distribution of tomosyn-1 (Stxbp5) and tomosyn-2 (Stxbp5l) in mouse hippocampal neurons and observed a mixed diffuse and punctate localization pattern of both isoforms. Tomosyn-1 accumulations were present in axons and dendrites. As expected, tomosyn-1 was expressed in about 75% of the presynaptic terminals. Interestingly, also bidirectional moving tomosyn-1 and -2 puncta were observed. Despite the lack of a membrane anchor these puncta co-migrated with synapsin and neuropeptide Y, markers for respectively SVs and DCVs. Genetic blockade of two known tomosyn interactions with synaptotagmin-1 and its cognate SNAREs did not abolish its vesicular co-migration, suggesting an interplay of protein interactions mediated by the WD40 and SNARE domains. We hypothesize that the vesicle-binding properties of tomosyns may control the delivery, pan-synaptic sharing and secretion of neuronal signaling molecules, exceeding its canonical role at the plasma membrane.
Collapse
Affiliation(s)
- Cornelia J. Geerts
- Department of Functional Genomics, Centre for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University, Amsterdam, The Netherlands
| | - Roberta Mancini
- Department of Functional Genomics, Centre for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University, Amsterdam, The Netherlands
| | - Ning Chen
- Molecular and Cellular Neurobiology, Centre for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University, Amsterdam, The Netherlands
| | - Frank T. W. Koopmans
- Department of Functional Genomics, Centre for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University, Amsterdam, The Netherlands
| | - Ka Wan Li
- Molecular and Cellular Neurobiology, Centre for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University, Amsterdam, The Netherlands
| | - August B. Smit
- Molecular and Cellular Neurobiology, Centre for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University, Amsterdam, The Netherlands
| | | | - Matthijs Verhage
- Department of Functional Genomics, Centre for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University, Amsterdam, The Netherlands
- Department of Clinical Genetics, VU Medical Center, Amsterdam, The Netherlands
| | - Alexander J. A. Groffen
- Department of Functional Genomics, Centre for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University, Amsterdam, The Netherlands
- Department of Clinical Genetics, VU Medical Center, Amsterdam, The Netherlands
| |
Collapse
|
32
|
Cooperative stochastic binding and unbinding explain synaptic size dynamics and statistics. PLoS Comput Biol 2017; 13:e1005668. [PMID: 28704399 PMCID: PMC5546711 DOI: 10.1371/journal.pcbi.1005668] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 08/07/2017] [Accepted: 06/30/2017] [Indexed: 11/28/2022] Open
Abstract
Synapses are dynamic molecular assemblies whose sizes fluctuate significantly over time-scales of hours and days. In the current study, we examined the possibility that the spontaneous microscopic dynamics exhibited by synaptic molecules can explain the macroscopic size fluctuations of individual synapses and the statistical properties of synaptic populations. We present a mesoscopic model, which ties the two levels. Its basic premise is that synaptic size fluctuations reflect cooperative assimilation and removal of molecules at a patch of postsynaptic membrane. The introduction of cooperativity to both assimilation and removal in a stochastic biophysical model of these processes, gives rise to features qualitatively similar to those measured experimentally: nanoclusters of synaptic scaffolds, fluctuations in synaptic sizes, skewed, stable size distributions and their scaling in response to perturbations. Our model thus points to the potentially fundamental role of cooperativity in dictating synaptic remodeling dynamics and offers a conceptual understanding of these dynamics in terms of central microscopic features and processes. Neurons communicate through specialized sites of cell–cell contact known as synapses. This vast set of connections is believed to be crucial for sensory processing, motor function, learning and memory. Experimental data from recent years suggest that synapses are not static structures, but rather dynamic assemblies of molecules that move in, out and between nearby synapses, with these dynamics driving changes in synaptic properties over time. Thus, in addition to changes directed by activity or other physiological signals, synapses also exhibit spontaneous changes that have particular dynamical and statistical signatures. Given the immense complexity of synapses at the molecular scale, how can one hope to understand the principles that govern these spontaneous changes and statistical signatures? Here we offer a mesoscopic modelling approach—situated between detailed microscopic and abstract macroscopic approaches—to advance this understanding. Our model, based on simplified biophysical assumptions, shows that spontaneous cooperative binding and unbinding of proteins at synaptic sites can give rise to dynamic and statistical signatures similar to those measured in experiments. Importantly, we find cooperativity to be indispensable in this regard. Our model thus offers a conceptual understanding of synaptic dynamics and statistical features in terms of a fundamental biological principle, namely cooperativity.
Collapse
|
33
|
Characterization of a Human Point Mutation of VGLUT3 (p.A211V) in the Rodent Brain Suggests a Nonuniform Distribution of the Transporter in Synaptic Vesicles. J Neurosci 2017; 37:4181-4199. [PMID: 28314816 DOI: 10.1523/jneurosci.0282-16.2017] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2016] [Revised: 02/21/2017] [Accepted: 02/23/2017] [Indexed: 11/21/2022] Open
Abstract
The atypical vesicular glutamate transporter type 3 (VGLUT3) is expressed by subpopulations of neurons using acetylcholine, GABA, or serotonin as neurotransmitters. In addition, VGLUT3 is expressed in the inner hair cells of the auditory system. A mutation (p.A211V) in the gene that encodes VGLUT3 is responsible for progressive deafness in two unrelated families. In this study, we investigated the consequences of the p.A211V mutation in cell cultures and in the CNS of a mutant mouse. The mutation substantially decreased VGLUT3 expression (-70%). We measured VGLUT3-p.A211V activity by vesicular uptake in BON cells, electrophysiological recording of isolated neurons, and its ability to stimulate serotonergic accumulation in cortical synaptic vesicles. Despite a marked loss of expression, the activity of the mutated isoform was only minimally altered. Furthermore, mutant mice displayed none of the behavioral alterations that have previously been reported in VGLUT3 knock-out mice. Finally, we used stimulated emission depletion microscopy to analyze how the mutation altered VGLUT3 distribution within the terminals of mice expressing the mutated isoform. The mutation appeared to reduce the expression of the VGLUT3 transporter by simultaneously decreasing the number of VGLUT3-positive synaptic vesicles and the amount of VGLUT3 per synapses. These observations suggested that VGLUT3 global activity is not linearly correlated with VGLUT3 expression. Furthermore, our data unraveled a nonuniform distribution of VGLUT3 in synaptic vesicles. Identifying the mechanisms responsible for this complex vesicular sorting will be critical to understand VGLUT's involvement in normal and pathological conditions.SIGNIFICANCE STATEMENT VGLUT3 is an atypical member of the vesicular glutamate transporter family. A point mutation of VGLUT3 (VGLUT3-p.A211V) responsible for a progressive loss of hearing has been identified in humans. We observed that this mutation dramatically reduces VGLUT3 expression in terminals (∼70%) without altering its function. Furthermore, using stimulated emission depletion microscopy, we found that reducing the expression levels of VGLUT3 diminished the number of VGLUT3-positive vesicles at synapses. These unexpected findings challenge the vision of a uniform distribution of synaptic vesicles at synapses. Therefore, the overall activity of VGLUT3 is not proportional to the level of VGLUT3 expression. These data will be key in interpreting the role of VGLUTs in human pathologies.
Collapse
|
34
|
Gilles JF, Dos Santos M, Boudier T, Bolte S, Heck N. DiAna, an ImageJ tool for object-based 3D co-localization and distance analysis. Methods 2017; 115:55-64. [DOI: 10.1016/j.ymeth.2016.11.016] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 11/22/2016] [Accepted: 11/22/2016] [Indexed: 12/16/2022] Open
|
35
|
Luquet E, Biesemann C, Munier A, Herzog E. Purification of Synaptosome Populations Using Fluorescence-Activated Synaptosome Sorting. Methods Mol Biol 2017; 1538:121-134. [PMID: 27943188 DOI: 10.1007/978-1-4939-6688-2_10] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
For several decades, neurobiologists have used subcellular fractionation methods to analyze the molecular structure and some functional features of the cells in the central nervous system. Indeed, brain tissue contains a complex intermingled network of neuronal, glial, and vascular cells. To reduce this complexity biochemists have optimized fractionation protocols that enrich in specific compartments such as synapses (called "synaptosomes") and synaptic vesicles, for example. However, recently, these approaches suffered from a lack of specificity and purity. In a recent effort, we extended the conventional synaptosome preparation to purify fluorescent synaptosomes on a cell sorter. We could prove that our method allows for the steep enrichment in fluorescent excitatory VGLUT1venus synaptosomes containing the presynaptic element and the tip of the post-synaptic element and a strong depletion in neuronal and glial contaminants. Here, we propose a detailed procedure for the implementation of Fluorescence Activated Synaptosome Sorting.
Collapse
Affiliation(s)
- Elisa Luquet
- Interdisciplinary Institute for Neuroscience, University Bordeaux, CNRS, UMR 5297, F-33000, Bordeaux, France
- Interdisciplinary Institute for NeuroScience, CNRS, UMR 5297, F-33000, Bordeaux, France
| | - Christoph Biesemann
- Department of Molecular Neurobiology, Max Planck Institute of Experimental Medicine, 37075, Göttingen, Germany
| | - Annie Munier
- Institut de Biologie Paris Seine, University Pierre et Marie Curie, IBPS, F-75005, Paris, France
| | - Etienne Herzog
- Interdisciplinary Institute for Neuroscience, University Bordeaux, CNRS, UMR 5297, F-33000, Bordeaux, France.
- Interdisciplinary Institute for NeuroScience, CNRS, UMR 5297, F-33000, Bordeaux, France.
| |
Collapse
|
36
|
Joensuu M, Padmanabhan P, Durisic N, Bademosi ATD, Cooper-Williams E, Morrow IC, Harper CB, Jung W, Parton RG, Goodhill GJ, Papadopulos A, Meunier FA. Subdiffractional tracking of internalized molecules reveals heterogeneous motion states of synaptic vesicles. J Cell Biol 2016; 215:277-292. [PMID: 27810917 PMCID: PMC5080683 DOI: 10.1083/jcb.201604001] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 09/30/2016] [Indexed: 11/23/2022] Open
Abstract
Joensuu et al. describe a tool for subdiffractional tracking of internalized molecules. They reveal that synaptic vesicles exhibit stochastic switching between heterogeneous diffusive and transport states in live hippocampal nerve terminals. Our understanding of endocytic pathway dynamics is severely restricted by the diffraction limit of light microscopy. To address this, we implemented a novel technique based on the subdiffractional tracking of internalized molecules (sdTIM). This allowed us to image anti–green fluorescent protein Atto647N-tagged nanobodies trapped in synaptic vesicles (SVs) from live hippocampal nerve terminals expressing vesicle-associated membrane protein 2 (VAMP2)–pHluorin with 36-nm localization precision. Our results showed that, once internalized, VAMP2–pHluorin/Atto647N–tagged nanobodies exhibited a markedly lower mobility than on the plasma membrane, an effect that was reversed upon restimulation in presynapses but not in neighboring axons. Using Bayesian model selection applied to hidden Markov modeling, we found that SVs oscillated between diffusive states or a combination of diffusive and transport states with opposite directionality. Importantly, SVs exhibiting diffusive motion were relatively less likely to switch to the transport motion. These results highlight the potential of the sdTIM technique to provide new insights into the dynamics of endocytic pathways in a wide variety of cellular settings.
Collapse
Affiliation(s)
- Merja Joensuu
- Clem Jones Centre for Ageing Dementia Research, The University of Queensland, Brisbane, Queensland 4072, Australia.,Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Pranesh Padmanabhan
- Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Nela Durisic
- Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Adekunle T D Bademosi
- Clem Jones Centre for Ageing Dementia Research, The University of Queensland, Brisbane, Queensland 4072, Australia.,Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia
| | | | - Isabel C Morrow
- Clem Jones Centre for Ageing Dementia Research, The University of Queensland, Brisbane, Queensland 4072, Australia.,Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Callista B Harper
- Clem Jones Centre for Ageing Dementia Research, The University of Queensland, Brisbane, Queensland 4072, Australia.,Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - WooRam Jung
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia.,Centre for Microscopy and Microanalysis, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Robert G Parton
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia.,Centre for Microscopy and Microanalysis, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Geoffrey J Goodhill
- Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia.,School of Mathematics and Physics, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Andreas Papadopulos
- Clem Jones Centre for Ageing Dementia Research, The University of Queensland, Brisbane, Queensland 4072, Australia .,Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Frédéric A Meunier
- Clem Jones Centre for Ageing Dementia Research, The University of Queensland, Brisbane, Queensland 4072, Australia .,Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia
| |
Collapse
|
37
|
Dvorkin R, Ziv NE. Relative Contributions of Specific Activity Histories and Spontaneous Processes to Size Remodeling of Glutamatergic Synapses. PLoS Biol 2016; 14:e1002572. [PMID: 27776122 PMCID: PMC5077109 DOI: 10.1371/journal.pbio.1002572] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2016] [Accepted: 09/27/2016] [Indexed: 11/18/2022] Open
Abstract
The idea that synaptic properties are defined by specific pre- and postsynaptic activity histories is one of the oldest and most influential tenets of contemporary neuroscience. Recent studies also indicate, however, that synaptic properties often change spontaneously, even in the absence of specific activity patterns or any activity whatsoever. What, then, are the relative contributions of activity history-dependent and activity history-independent processes to changes synapses undergo? To compare the relative contributions of these processes, we imaged, in spontaneously active networks of cortical neurons, glutamatergic synapses formed between the same axons and neurons or dendrites under the assumption that their similar activity histories should result in similar size changes over timescales of days. The size covariance of such commonly innervated (CI) synapses was then compared to that of synapses formed by different axons (non-CI synapses) that differed in their activity histories. We found that the size covariance of CI synapses was greater than that of non-CI synapses; yet overall size covariance of CI synapses was rather modest. Moreover, momentary and time-averaged sizes of CI synapses correlated rather poorly, in perfect agreement with published electron microscopy-based measurements of mouse cortex synapses. A conservative estimate suggested that ~40% of the observed size remodeling was attributable to specific activity histories, whereas ~10% and ~50% were attributable to cell-wide and spontaneous, synapse-autonomous processes, respectively. These findings demonstrate that histories of naturally occurring activity patterns can direct glutamatergic synapse remodeling but also suggest that the contributions of spontaneous, possibly stochastic, processes are at least as great.
Collapse
Affiliation(s)
- Roman Dvorkin
- Technion Faculty of Medicine, Network Biology Research Laboratories, Lorry Lokey Center for Life Sciences and Engineering, Technion, Haifa, Israel
| | - Noam E Ziv
- Technion Faculty of Medicine, Network Biology Research Laboratories, Lorry Lokey Center for Life Sciences and Engineering, Technion, Haifa, Israel.,Rappaport Family Institute for Research in the Medical Sciences, Haifa, Israel
| |
Collapse
|
38
|
Rothman JS, Kocsis L, Herzog E, Nusser Z, Silver RA. Physical determinants of vesicle mobility and supply at a central synapse. eLife 2016; 5. [PMID: 27542193 PMCID: PMC5025287 DOI: 10.7554/elife.15133] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Accepted: 08/14/2016] [Indexed: 12/22/2022] Open
Abstract
Encoding continuous sensory variables requires sustained synaptic signalling. At several sensory synapses, rapid vesicle supply is achieved via highly mobile vesicles and specialized ribbon structures, but how this is achieved at central synapses without ribbons is unclear. Here we examine vesicle mobility at excitatory cerebellar mossy fibre synapses which sustain transmission over a broad frequency bandwidth. Fluorescent recovery after photobleaching in slices from VGLUT1Venus knock-in mice reveal 75% of VGLUT1-containing vesicles have a high mobility, comparable to that at ribbon synapses. Experimentally constrained models establish hydrodynamic interactions and vesicle collisions are major determinants of vesicle mobility in crowded presynaptic terminals. Moreover, models incorporating 3D reconstructions of vesicle clouds near active zones (AZs) predict the measured releasable pool size and replenishment rate from the reserve pool. They also show that while vesicle reloading at AZs is not diffusion-limited at the onset of release, diffusion limits vesicle reloading during sustained high-frequency signalling. DOI:http://dx.doi.org/10.7554/eLife.15133.001
Collapse
Affiliation(s)
- Jason Seth Rothman
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, United Kingdom
| | - Laszlo Kocsis
- Laboratory of Cellular Neurophysiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Etienne Herzog
- Department of Molecular Neurobiology, Max Planck Institute of Experimental Medicine, Göttingen, Germany.,Team Synapse in Cognition, Interdisciplinary Institute for Neuroscience, Université de Bordeaux, UMR 5297, F-33000, Bordeaux, France
| | - Zoltan Nusser
- Laboratory of Cellular Neurophysiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Robin Angus Silver
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, United Kingdom
| |
Collapse
|
39
|
Pinto MJ, Alves PL, Martins L, Pedro JR, Ryu HR, Jeon NL, Taylor AM, Almeida RD. The proteasome controls presynaptic differentiation through modulation of an on-site pool of polyubiquitinated conjugates. J Cell Biol 2016; 212:789-801. [PMID: 27022091 PMCID: PMC4810304 DOI: 10.1083/jcb.201509039] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 02/24/2016] [Indexed: 11/22/2022] Open
Abstract
The intra-axonal events governing formation of presynaptic terminals are still poorly understood. Pinto et al. reveal a mechanism by which a localized decrease in proteasome degradation and resultant accumulation of polyubiquitinated proteins at nascent sites signal assembly of presynaptic terminals. Differentiation of the presynaptic terminal is a complex and rapid event that normally occurs in spatially specific axonal regions distant from the soma; thus, it is believed to be dependent on intra-axonal mechanisms. However, the full nature of the local events governing presynaptic assembly remains unknown. Herein, we investigated the involvement of the ubiquitin–proteasome system (UPS), the major degradative pathway, in the local modulation of presynaptic differentiation. We found that proteasome inhibition has a synaptogenic effect on isolated axons. In addition, formation of a stable cluster of synaptic vesicles onto a postsynaptic partner occurs in parallel to an on-site decrease in proteasome degradation. Accumulation of ubiquitinated proteins at nascent sites is a local trigger for presynaptic clustering. Finally, proteasome-related ubiquitin chains (K11 and K48) function as signals for the assembly of presynaptic terminals. Collectively, we propose a new axon-intrinsic mechanism for presynaptic assembly through local UPS inhibition. Subsequent on-site accumulation of proteins in their polyubiquitinated state triggers formation of presynapses.
Collapse
Affiliation(s)
- Maria J Pinto
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal PhD Program in Experimental Biology and Biomedicine, Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal
| | - Pedro L Alves
- Instituto de Educação e Cidadania, 3770-033 Mamarrosa, Portugal
| | - Luís Martins
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal
| | - Joana R Pedro
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal
| | - Hyun R Ryu
- Institute of Advanced Machinery and Design, Seoul National University, Seoul 151-744, Korea
| | - Noo Li Jeon
- Institute of Advanced Machinery and Design, Seoul National University, Seoul 151-744, Korea Department of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-744, Korea
| | - Anne M Taylor
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Chapel Hill, NC 27599
| | - Ramiro D Almeida
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal Institute for Interdisciplinary Research, University of Coimbra, 3004-517 Coimbra, Portugal School of Allied Health Technologies, Polytechnic Institute of Porto, 4400-330 Vila Nova de Gaia, Portugal
| |
Collapse
|
40
|
Danbolt NC, Zhou Y, Furness DN, Holmseth S. Strategies for immunohistochemical protein localization using antibodies: What did we learn from neurotransmitter transporters in glial cells and neurons. Glia 2016; 64:2045-2064. [PMID: 27458697 DOI: 10.1002/glia.23027] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 06/19/2016] [Accepted: 06/21/2016] [Indexed: 12/11/2022]
Abstract
Immunocytochemistry and Western blotting are still major methods for protein localization, but they rely on the specificity of the antibodies. Validation of antibody specificity remains challenging mostly because ideal negative controls are often unavailable. Further, immunochemical labeling patterns are also influenced by a number of other factors such as postmortem changes, fixation procedures and blocking agents as well as the general assay conditions (e.g., buffers, temperature, etc.). Western blotting similarly depends on tissue collection and sample preparation as well as the electrophoretic separation, transfer to blotting membranes and the immunochemical probing of immobilized molecules. Publication of inaccurate information on protein distribution has downstream consequences for other researchers because the interpretation of physiological and pharmacological observations depends on information on where ion channels, receptors, enzymes or transporters are located. Despite numerous reports, some of which are strongly worded, erroneous localization data are being published. Here we describe the extent of the problem and illustrate the nature of the pitfalls with examples from studies of neurotransmitter transporters. We explain the importance of supplementing immunochemical observations with other measurements (e.g., mRNA levels and distribution, protein activity, mass spectrometry, electrophysiological recordings, etc.) and why quantitative considerations are integral parts of the quality control. Further, we propose a practical strategy for researchers who plan to embark on a localization study. We also share our thoughts about guidelines for quality control. GLIA 2016;64:2045-2064.
Collapse
Affiliation(s)
- Niels Christian Danbolt
- Neurotransporter Group, Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway.
| | - Yun Zhou
- Neurotransporter Group, Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - David N Furness
- School of Life Sciences, Keele University, Keele, Staffs, United Kingdom
| | - Silvia Holmseth
- Neurotransporter Group, Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| |
Collapse
|
41
|
Chen CY, Chen YT, Wang JY, Huang YS, Tai CY. Postsynaptic Y654 dephosphorylation of β-catenin modulates presynaptic vesicle turnover through increased n-cadherin-mediated transsynaptic signaling. Dev Neurobiol 2016; 77:61-74. [PMID: 27328456 DOI: 10.1002/dneu.22411] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Revised: 04/26/2016] [Accepted: 06/18/2016] [Indexed: 11/08/2022]
Abstract
Synaptic adhesion molecules, which coordinately control structural and functional changes at both sides of synapses, are important for synaptogenesis and synaptic plasticity. Because they physically form homophilic or heterophilic adhesions across synaptic junctions, these molecules can initiate transsynaptic communication in both anterograde and retrograde directions. Using optical imaging approaches, we investigated whether an increase in postsynaptic N-cadherin could correspondingly alter the function of connected presynaptic terminals. Postsynaptic expression of β-catenin Y654F, a phosphorylation-defective form with enhanced binding to N-cadherin, is sufficient to increase postsynaptic surface levels of N-cadherin and consequently promote presynaptic reorganizations. Such reorganizations include increases in the densities of the synaptic vesicle protein, Synaptotagmin 1 and the active zone scaffold protein, Bassoon, the number of active boutons and the size of the total recycling vesicle pool. In contrast, synaptic vesicle turnover is significantly impaired, preventing the exchange of synaptic vesicles with adjacent boutons. Together, N-cadherin-mediated retrograde signaling, governed by phosphoregulation of postsynaptic β-catenin Y654, coordinately modulates presynaptic vesicle dynamics to enhance synaptic communication in mature neurons. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 61-74, 2017.
Collapse
Affiliation(s)
- Chin-Yi Chen
- Institute of Molecular Biology, Academia Sinica, Taipei, 11529, Taiwan.,Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, 11490, Taiwan.,Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan
| | - Yi-Ting Chen
- Molecular Cell Biology, Taiwan International Graduate Program, Academia Sinica, and Graduate Institute of Life Sciences, National Defense Center, Taipei 11490, Taiwan
| | - Jen-Yeu Wang
- Institute of Molecular Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Yi-Shuian Huang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan
| | - Chin-Yin Tai
- Institute of Molecular Biology, Academia Sinica, Taipei, 11529, Taiwan.,Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, 11490, Taiwan.,Institute of Biologics, Development Center for Biotechnology, New Taipei City, 22180, Taiwan
| |
Collapse
|
42
|
Pinto MJ, Pedro JR, Costa RO, Almeida RD. Visualizing K48 Ubiquitination during Presynaptic Formation By Ubiquitination-Induced Fluorescence Complementation (UiFC). Front Mol Neurosci 2016; 9:43. [PMID: 27375430 PMCID: PMC4901079 DOI: 10.3389/fnmol.2016.00043] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 05/24/2016] [Indexed: 11/18/2022] Open
Abstract
In recent years, signaling through ubiquitin has been shown to be of great importance for normal brain development. Indeed, fluctuations in ubiquitin levels and spontaneous mutations in (de)ubiquitination enzymes greatly perturb synapse formation and neuronal transmission. In the brain, expression of lysine (K) 48-linked ubiquitin chains is higher at a developmental stage coincident with synaptogenesis. Nevertheless, no studies have so far delved into the involvement of this type of polyubiquitin chains in synapse formation. We have recently proposed a role for polyubiquitinated conjugates as triggering signals for presynaptic assembly. Herein, we aimed at characterizing the axonal distribution of K48 polyubiquitin and its dynamics throughout the course of presynaptic formation. To accomplish so, we used an ubiquitination-induced fluorescence complementation (UiFC) strategy for the visualization of K48 polyubiquitin in live hippocampal neurons. We first validated its use in neurons by analyzing changing levels of polyubiquitin. UiFC signal is diffusely distributed with distinct aggregates in somas, dendrites and axons, which perfectly colocalize with staining for a K48-specific antibody. Axonal UiFC aggregates are relatively stable and new aggregates are formed as an axon grows. Approximately 65% of UiFC aggregates colocalize with synaptic vesicle clusters and they preferentially appear in the axonal domains of axo-somatodendritic synapses when compared to isolated axons. We then evaluated axonal accumulation of K48 ubiquitinated signals in bead-induced synapses. We observed rapid accumulation of UiFC signal and endogenous K48 ubiquitin at the sites of newly formed presynapses. Lastly, we show by means of a microfluidic platform, for the isolation of axons, that presynaptic clustering on beads is dependent on E1-mediated ubiquitination at the axonal level. Altogether, these results indicate that enrichment of K48 polyubiquitin at the site of nascent presynaptic terminals is an important axon-intrinsic event for presynaptic differentiation.
Collapse
Affiliation(s)
- Maria J Pinto
- Center for Neuroscience and Cell Biology (CNC), University of CoimbraCoimbra, Portugal; PhD Programme in Experimental Biology and Biomedicine (PDBEB), Center for Neuroscience and Cell Biology, University of CoimbraCoimbra, Portugal
| | - Joana R Pedro
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra Coimbra, Portugal
| | - Rui O Costa
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra Coimbra, Portugal
| | - Ramiro D Almeida
- Center for Neuroscience and Cell Biology (CNC), University of CoimbraCoimbra, Portugal; School of Allied Health Technologies, Polytechnic Institute of Porto (ESTSP-IPP)Vila Nova de Gaia, Portugal; Institute for Interdisciplinary Research, University of CoimbraCoimbra, Portugal
| |
Collapse
|
43
|
|
44
|
Heise C, Schroeder JC, Schoen M, Halbedl S, Reim D, Woelfle S, Kreutz MR, Schmeisser MJ, Boeckers TM. Selective Localization of Shanks to VGLUT1-Positive Excitatory Synapses in the Mouse Hippocampus. Front Cell Neurosci 2016; 10:106. [PMID: 27199660 PMCID: PMC4844616 DOI: 10.3389/fncel.2016.00106] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2016] [Accepted: 04/11/2016] [Indexed: 12/13/2022] Open
Abstract
Members of the Shank family of multidomain proteins (Shank1, Shank2, and Shank3) are core components of the postsynaptic density (PSD) of excitatory synapses. At synaptic sites Shanks serve as scaffolding molecules that cluster neurotransmitter receptors as well as cell adhesion molecules attaching them to the actin cytoskeleton. In this study we investigated the synapse specific localization of Shank1-3 and focused on well-defined synaptic contacts within the hippocampal formation. We found that all three family members are present only at VGLUT1-positive synapses, which is particularly visible at mossy fiber contacts. No costaining was found at VGLUT2-positive contacts indicating that the molecular organization of VGLUT2-associated PSDs diverges from classical VGLUT1-positive excitatory contacts in the hippocampus. In light of SHANK mutations in neuropsychiatric disorders, this study indicates which glutamatergic networks within the hippocampus will be primarily affected by shankopathies.
Collapse
Affiliation(s)
- Christopher Heise
- Institute for Anatomy and Cell Biology, Ulm UniversityUlm, Germany; RG Neuroplasticity, Leibniz Institute for NeurobiologyMagdeburg, Germany
| | - Jan C Schroeder
- Institute for Anatomy and Cell Biology, Ulm University Ulm, Germany
| | - Michael Schoen
- Institute for Anatomy and Cell Biology, Ulm University Ulm, Germany
| | - Sonja Halbedl
- Institute for Anatomy and Cell Biology, Ulm University Ulm, Germany
| | - Dominik Reim
- Institute for Anatomy and Cell Biology, Ulm University Ulm, Germany
| | - Sarah Woelfle
- Institute for Anatomy and Cell Biology, Ulm University Ulm, Germany
| | - Michael R Kreutz
- RG Neuroplasticity, Leibniz Institute for Neurobiology Magdeburg, Germany
| | - Michael J Schmeisser
- Institute for Anatomy and Cell Biology, Ulm UniversityUlm, Germany; Department of Neurology, Ulm UniversityUlm, Germany
| | | |
Collapse
|
45
|
Deehan GA, Hauser SR, Waeiss RA, Knight CP, Toalston JE, Truitt WA, McBride WJ, Rodd ZA. Co-administration of ethanol and nicotine: the enduring alterations in the rewarding properties of nicotine and glutamate activity within the mesocorticolimbic system of female alcohol-preferring (P) rats. Psychopharmacology (Berl) 2015; 232:4293-302. [PMID: 26306917 PMCID: PMC4899841 DOI: 10.1007/s00213-015-4056-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 08/17/2015] [Indexed: 12/21/2022]
Abstract
RATIONALE The co-abuse of ethanol (EtOH) and nicotine (NIC) increases the likelihood that an individual will relapse to drug use while attempting to maintain abstinence. There is limited research examining the consequences of long-term EtOH and NIC co-abuse. OBJECTIVES The current experiments determined the enduring effects of chronic EtOH, NIC, or EtOH + NIC intake on the reinforcing properties of NIC and glutamate (GLU) activity within the mesocorticolimbic (MCL) system. METHODS Alcohol-preferring (P) rats self-administered EtOH, Sacc + NIC, or EtOH + NIC combined for 10 weeks. The reinforcing properties of 0.1-3.0 μM NIC within the nucleus accumbens shell (AcbSh) were assessed following a 2-3-week drug-free period using intracranial self-administration (ICSA) procedures. The effects of EtOH, Sacc, Sacc + NIC, or EtOH + NIC intake on extracellular levels and clearance of glutamate (GLU) in the medial prefrontal cortex (mPFC) were also determined. RESULTS Binge intake of EtOH (96-100 mg%) and NIC (21-27 mg/mL) were attained. All groups of P rats self-infused 3.0 μM NIC directly into the AcbSh, whereas only animals in the EtOH + NIC co-abuse group self-infused the 0.3 and 1.0 μM NIC concentrations. Additionally, self-administration of EtOH + NIC, but not EtOH, Sacc or Sacc + NIC, resulted in enduring increases in basal extracellular GLU levels in the mPFC. CONCLUSIONS Overall, the co-abuse of EtOH + NIC produced enduring neuronal alterations within the MCL which enhanced the rewarding properties of NIC in the AcbSh and elevated extracellular GLU levels within the mPFC.
Collapse
Affiliation(s)
- Gerald A Deehan
- Department of Psychiatry, Institute of Psychiatric Research, Indiana University School of Medicine, Neuroscience Research Building, 320 West 15th St, Indianapolis, IN, 46202-2266, USA.
| | - Sheketha R Hauser
- Department of Psychiatry, Institute of Psychiatric Research, Indiana University School of Medicine, Neuroscience Research Building, 320 West 15th St, Indianapolis, IN, 46202-2266, USA
| | - R Aaron Waeiss
- Department of Psychiatry, Institute of Psychiatric Research, Indiana University School of Medicine, Neuroscience Research Building, 320 West 15th St, Indianapolis, IN, 46202-2266, USA
| | - Christopher P Knight
- Department of Psychiatry, Institute of Psychiatric Research, Indiana University School of Medicine, Neuroscience Research Building, 320 West 15th St, Indianapolis, IN, 46202-2266, USA
| | - Jamie E Toalston
- Department of Psychiatry, Institute of Psychiatric Research, Indiana University School of Medicine, Neuroscience Research Building, 320 West 15th St, Indianapolis, IN, 46202-2266, USA
| | - William A Truitt
- Department of Psychiatry, Institute of Psychiatric Research, Indiana University School of Medicine, Neuroscience Research Building, 320 West 15th St, Indianapolis, IN, 46202-2266, USA
| | - William J McBride
- Department of Psychiatry, Institute of Psychiatric Research, Indiana University School of Medicine, Neuroscience Research Building, 320 West 15th St, Indianapolis, IN, 46202-2266, USA
| | - Zachary A Rodd
- Department of Psychiatry, Institute of Psychiatric Research, Indiana University School of Medicine, Neuroscience Research Building, 320 West 15th St, Indianapolis, IN, 46202-2266, USA
| |
Collapse
|
46
|
Remodeling and Tenacity of Inhibitory Synapses: Relationships with Network Activity and Neighboring Excitatory Synapses. PLoS Comput Biol 2015; 11:e1004632. [PMID: 26599330 PMCID: PMC4658206 DOI: 10.1371/journal.pcbi.1004632] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2015] [Accepted: 10/29/2015] [Indexed: 11/19/2022] Open
Abstract
Glutamatergic synapse size remodeling is governed not only by specific activity forms but also by apparently stochastic processes with well-defined statistics. These spontaneous remodeling processes can give rise to skewed and stable synaptic size distributions, underlie scaling of these distributions and drive changes in glutamatergic synapse size "configurations". Where inhibitory synapses are concerned, however, little is known on spontaneous remodeling dynamics, their statistics, their activity dependence or their long-term consequences. Here we followed individual inhibitory synapses for days, and analyzed their size remodeling dynamics within the statistical framework previously developed for glutamatergic synapses. Similar to glutamatergic synapses, size distributions of inhibitory synapses were skewed and stable; at the same time, however, sizes of individual synapses changed considerably, leading to gradual changes in synaptic size configurations. The suppression of network activity only transiently affected spontaneous remodeling dynamics, did not affect synaptic size configuration change rates and was not followed by the scaling of inhibitory synapse size distributions. Comparisons with glutamatergic synapses within the same dendrites revealed a degree of coupling between nearby inhibitory and excitatory synapse remodeling, but also revealed that inhibitory synapse size configurations changed at considerably slower rates than those of their glutamatergic neighbors. These findings point to quantitative differences in spontaneous remodeling dynamics of inhibitory and excitatory synapses but also reveal deep qualitative similarities in the processes that control their sizes and govern their remodeling dynamics.
Collapse
|
47
|
Fouquet C, Gilles JF, Heck N, Dos Santos M, Schwartzmann R, Cannaya V, Morel MP, Davidson RS, Trembleau A, Bolte S. Improving axial resolution in confocal microscopy with new high refractive index mounting media. PLoS One 2015; 10:e0121096. [PMID: 25822785 PMCID: PMC4379090 DOI: 10.1371/journal.pone.0121096] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Accepted: 02/09/2015] [Indexed: 11/23/2022] Open
Abstract
Resolution, high signal intensity and elevated signal to noise ratio (SNR) are key issues for biologists who aim at studying the localisation of biological structures at the cellular and subcellular levels using confocal microscopy. The resolution required to separate sub-cellular biological structures is often near to the resolving power of the microscope. When optimally used, confocal microscopes may reach resolutions of 180 nm laterally and 500 nm axially, however, axial resolution in depth is often impaired by spherical aberration that may occur due to refractive index mismatches. Spherical aberration results in broadening of the point-spread function (PSF), a decrease in peak signal intensity when imaging in depth and a focal shift that leads to the distortion of the image along the z-axis and thus in a scaling error. In this study, we use the novel mounting medium CFM3 (Citifluor Ltd., UK) with a refractive index of 1.518 to minimize the effects of spherical aberration. This mounting medium is compatible with most common fluorochromes and fluorescent proteins. We compare its performance with established mounting media, harbouring refractive indices below 1.500, by estimating lateral and axial resolution with sub-resolution fluorescent beads. We show furthermore that the use of the high refractive index media renders the tissue transparent and improves considerably the axial resolution and imaging depth in immuno-labelled or fluorescent protein labelled fixed mouse brain tissue. We thus propose to use those novel high refractive index mounting media, whenever optimal axial resolution is required.
Collapse
Affiliation(s)
- Coralie Fouquet
- Sorbonne Universités, UPMC Univ Paris 06, F-75005, Paris, France
- Institut de Biologie Paris-Seine, CNRS FR3631, F-75005, Paris, France
- CNRS, UMR8246, INSERM, U1130, Neuroscience Paris Seine, F-75005, Paris, France
| | - Jean-François Gilles
- Sorbonne Universités, UPMC Univ Paris 06, F-75005, Paris, France
- Institut de Biologie Paris-Seine, CNRS FR3631, F-75005, Paris, France
| | - Nicolas Heck
- Sorbonne Universités, UPMC Univ Paris 06, F-75005, Paris, France
- Institut de Biologie Paris-Seine, CNRS FR3631, F-75005, Paris, France
- CNRS, UMR8246, INSERM, U1130, Neuroscience Paris Seine, F-75005, Paris, France
| | - Marc Dos Santos
- Sorbonne Universités, UPMC Univ Paris 06, F-75005, Paris, France
- Institut de Biologie Paris-Seine, CNRS FR3631, F-75005, Paris, France
- CNRS, UMR8246, INSERM, U1130, Neuroscience Paris Seine, F-75005, Paris, France
| | - Richard Schwartzmann
- Sorbonne Universités, UPMC Univ Paris 06, F-75005, Paris, France
- Institut de Biologie Paris-Seine, CNRS FR3631, F-75005, Paris, France
| | - Vidjeacoumary Cannaya
- Sorbonne Universités, UPMC Univ Paris 06, F-75005, Paris, France
- Institut de Biologie Paris-Seine, CNRS FR3631, F-75005, Paris, France
- CNRS, UMR8246, INSERM, U1130, Neuroscience Paris Seine, F-75005, Paris, France
| | - Marie-Pierre Morel
- Sorbonne Universités, UPMC Univ Paris 06, F-75005, Paris, France
- Institut de Biologie Paris-Seine, CNRS FR3631, F-75005, Paris, France
- CNRS, UMR8246, INSERM, U1130, Neuroscience Paris Seine, F-75005, Paris, France
| | | | - Alain Trembleau
- Sorbonne Universités, UPMC Univ Paris 06, F-75005, Paris, France
- Institut de Biologie Paris-Seine, CNRS FR3631, F-75005, Paris, France
- CNRS, UMR8246, INSERM, U1130, Neuroscience Paris Seine, F-75005, Paris, France
| | - Susanne Bolte
- Sorbonne Universités, UPMC Univ Paris 06, F-75005, Paris, France
- Institut de Biologie Paris-Seine, CNRS FR3631, F-75005, Paris, France
- * E-mail:
| |
Collapse
|
48
|
Synaptic vesicle pools: Principles, properties and limitations. Exp Cell Res 2015; 335:150-6. [PMID: 25814361 DOI: 10.1016/j.yexcr.2015.03.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 03/14/2015] [Indexed: 11/21/2022]
|
49
|
Live imaging of endogenous PSD-95 using ENABLED: a conditional strategy to fluorescently label endogenous proteins. J Neurosci 2015; 34:16698-712. [PMID: 25505322 DOI: 10.1523/jneurosci.3888-14.2014] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Stoichiometric labeling of endogenous synaptic proteins for high-contrast live-cell imaging in brain tissue remains challenging. Here, we describe a conditional mouse genetic strategy termed endogenous labeling via exon duplication (ENABLED), which can be used to fluorescently label endogenous proteins with near ideal properties in all neurons, a sparse subset of neurons, or specific neuronal subtypes. We used this method to label the postsynaptic density protein PSD-95 with mVenus without overexpression side effects. We demonstrated that mVenus-tagged PSD-95 is functionally equivalent to wild-type PSD-95 and that PSD-95 is present in nearly all dendritic spines in CA1 neurons. Within spines, while PSD-95 exhibited low mobility under basal conditions, its levels could be regulated by chronic changes in neuronal activity. Notably, labeled PSD-95 also allowed us to visualize and unambiguously examine otherwise-unidentifiable excitatory shaft synapses in aspiny neurons, such as parvalbumin-positive interneurons and dopaminergic neurons. Our results demonstrate that the ENABLED strategy provides a valuable new approach to study the dynamics of endogenous synaptic proteins in vivo.
Collapse
|
50
|
Sahel A, Ortiz FC, Kerninon C, Maldonado PP, Angulo MC, Nait-Oumesmar B. Alteration of synaptic connectivity of oligodendrocyte precursor cells following demyelination. Front Cell Neurosci 2015; 9:77. [PMID: 25852473 PMCID: PMC4362325 DOI: 10.3389/fncel.2015.00077] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Accepted: 02/21/2014] [Indexed: 11/13/2022] Open
Abstract
Oligodendrocyte precursor cells (OPCs) are a major source of remyelinating oligodendrocytes in demyelinating diseases such as Multiple Sclerosis (MS). While OPCs are innervated by unmyelinated axons in the normal brain, the fate of such synaptic contacts after demyelination is still unclear. By combining electrophysiology and immunostainings in different transgenic mice expressing fluorescent reporters, we studied the synaptic innervation of OPCs in the model of lysolecithin (LPC)-induced demyelination of corpus callosum. Synaptic innervation of reactivated OPCs in the lesion was revealed by the presence of AMPA receptor-mediated synaptic currents, VGluT1+ axon-OPC contacts in 3D confocal reconstructions and synaptic junctions observed by electron microscopy. Moreover, 3D confocal reconstructions of VGluT1 and NG2 immunolabeling showed the existence of glutamatergic axon-OPC contacts in post-mortem MS lesions. Interestingly, patch-clamp recordings in LPC-induced lesions demonstrated a drastic decrease in spontaneous synaptic activity of OPCs early after demyelination that was not caused by an impaired conduction of compound action potentials. A reduction in synaptic connectivity was confirmed by the lack of VGluT1+ axon-OPC contacts in virtually all rapidly proliferating OPCs stained with EdU (50-ethynyl-20-deoxyuridine). At the end of the massive proliferation phase in lesions, the proportion of innervated OPCs rapidly recovers, although the frequency of spontaneous synaptic currents did not reach control levels. In conclusion, our results demonstrate that newly-generated OPCs do not receive synaptic inputs during their active proliferation after demyelination, but gain synapses during the remyelination process. Hence, glutamatergic synaptic inputs may contribute to inhibit OPC proliferation and might have a physiopathological relevance in demyelinating disorders.
Collapse
Affiliation(s)
- Aurélia Sahel
- INSERM U1127, Institut du Cerveau et de la Moelle Epinière Paris, France ; Université Paris 6, Sorbonne Paris Cité, UMR-S1127 Paris, France ; Centre National de la Recherche Scientifique UMR 7225 Paris, France
| | - Fernando C Ortiz
- INSERM U1128 Paris, France ; Université Paris Descartes, Sorbonne Paris Cité Paris, France
| | - Christophe Kerninon
- INSERM U1127, Institut du Cerveau et de la Moelle Epinière Paris, France ; Université Paris 6, Sorbonne Paris Cité, UMR-S1127 Paris, France ; Centre National de la Recherche Scientifique UMR 7225 Paris, France
| | - Paloma P Maldonado
- INSERM U1128 Paris, France ; Université Paris Descartes, Sorbonne Paris Cité Paris, France
| | - María Cecilia Angulo
- INSERM U1128 Paris, France ; Université Paris Descartes, Sorbonne Paris Cité Paris, France
| | - Brahim Nait-Oumesmar
- INSERM U1127, Institut du Cerveau et de la Moelle Epinière Paris, France ; Université Paris 6, Sorbonne Paris Cité, UMR-S1127 Paris, France ; Centre National de la Recherche Scientifique UMR 7225 Paris, France
| |
Collapse
|