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Exertier C, Antonelli L, Fiorillo A, Bernardini R, Colotti B, Ilari A, Colotti G. Sorcin in Cancer Development and Chemotherapeutic Drug Resistance. Cancers (Basel) 2024; 16:2810. [PMID: 39199583 PMCID: PMC11352664 DOI: 10.3390/cancers16162810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2024] [Revised: 07/31/2024] [Accepted: 08/08/2024] [Indexed: 09/01/2024] Open
Abstract
SOluble Resistance-related Calcium-binding proteIN (sorcin) earned its name due to its co-amplification with ABCB1 in multidrug-resistant cells. Initially thought to be an accidental consequence of this co-amplification, recent research indicates that sorcin plays a more active role as an oncoprotein, significantly impacting multidrug resistance (MDR). Sorcin is a highly expressed calcium-binding protein, often overproduced in human tumors and multidrug-resistant cancers, and is a promising novel MDR marker. In tumors, sorcin levels inversely correlate with both patient response to chemotherapy and overall prognosis. Multidrug-resistant cell lines consistently exhibit higher sorcin expression compared to their parental counterparts. Furthermore, sorcin overexpression via gene transfection enhances drug resistance to various chemotherapeutic drugs across numerous cancer lines. Conversely, silencing sorcin expression reverses drug resistance in many cell lines. Sorcin participates in several mechanisms of MDR, including drug efflux, drug sequestering, cell death inhibition, gene amplification, epithelial-to-mesenchymal transition, angiogenesis, and metastasis. The present review focuses on the structure and function of sorcin, on sorcin's role in cancer and drug resistance, and on the approaches aimed at targeting sorcin.
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Affiliation(s)
- Cécile Exertier
- Institute of Molecular Biology and Pathology, Italian National Research Council (IBPM-CNR), c/o Department Biochemical Sciences, Sapienza University of Rome, Ed. CU027, P.le A.Moro 5, 00185 Rome, Italy; (C.E.); (A.I.)
| | - Lorenzo Antonelli
- Department Biochemical Sciences, Sapienza University of Rome, Ed. CU027, P.le A.Moro 5, 00185 Rome, Italy; (L.A.); (A.F.)
| | - Annarita Fiorillo
- Department Biochemical Sciences, Sapienza University of Rome, Ed. CU027, P.le A.Moro 5, 00185 Rome, Italy; (L.A.); (A.F.)
| | - Roberta Bernardini
- Department of Clinical Sciences and Translational Medicine, University of Rome “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy;
| | - Beatrice Colotti
- Child Neuropsychiatry Unit, Child Neuropsychiatry School, University Hospital of Tor Vergata, Via Montpellier 1, 00133 Rome, Italy;
| | - Andrea Ilari
- Institute of Molecular Biology and Pathology, Italian National Research Council (IBPM-CNR), c/o Department Biochemical Sciences, Sapienza University of Rome, Ed. CU027, P.le A.Moro 5, 00185 Rome, Italy; (C.E.); (A.I.)
| | - Gianni Colotti
- Institute of Molecular Biology and Pathology, Italian National Research Council (IBPM-CNR), c/o Department Biochemical Sciences, Sapienza University of Rome, Ed. CU027, P.le A.Moro 5, 00185 Rome, Italy; (C.E.); (A.I.)
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2
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Jackson J, Hoffmann C, Scifo E, Wang H, Wischhof L, Piazzesi A, Mondal M, Shields H, Zhou X, Mondin M, Ryan EB, Döring H, Prehn JHM, Rottner K, Giannone G, Nicotera P, Ehninger D, Milovanovic D, Bano D. Actin-nucleation promoting factor N-WASP influences alpha-synuclein condensates and pathology. Cell Death Dis 2024; 15:304. [PMID: 38693139 PMCID: PMC11063037 DOI: 10.1038/s41419-024-06686-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 04/07/2024] [Accepted: 04/16/2024] [Indexed: 05/03/2024]
Abstract
Abnormal intraneuronal accumulation of soluble and insoluble α-synuclein (α-Syn) is one of the main pathological hallmarks of synucleinopathies, such as Parkinson's disease (PD). It has been well documented that the reversible liquid-liquid phase separation of α-Syn can modulate synaptic vesicle condensates at the presynaptic terminals. However, α-Syn can also form liquid-like droplets that may convert into amyloid-enriched hydrogels or fibrillar polymorphs under stressful conditions. To advance our understanding on the mechanisms underlying α-Syn phase transition, we employed a series of unbiased proteomic analyses and found that actin and actin regulators are part of the α-Syn interactome. We focused on Neural Wiskott-Aldrich syndrome protein (N-WASP) because of its association with a rare early-onset familial form of PD. In cultured cells, we demonstrate that N-WASP undergoes phase separation and can be recruited to synapsin 1 liquid-like droplets, whereas it is excluded from α-Syn/synapsin 1 condensates. Consistently, we provide evidence that wsp-1/WASL loss of function alters the number and dynamics of α-Syn inclusions in the nematode Caenorhabditis elegans. Together, our findings indicate that N-WASP expression may create permissive conditions that promote α-Syn condensates and their potentially deleterious conversion into toxic species.
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Affiliation(s)
- Joshua Jackson
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Christian Hoffmann
- German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany
- Einstein Center for Neuroscience, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Enzo Scifo
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Han Wang
- German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany
| | - Lena Wischhof
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Antonia Piazzesi
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | | | - Hanna Shields
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Xuesi Zhou
- University Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, Bordeaux, France
| | - Magali Mondin
- University Bordeaux, CNRS, INSERM, BIC, UAR 3420, F-33000, Bordeaux, France
| | - Eanna B Ryan
- RCSI Centre for Systems Medicine and Department of Physiology and Medical Physics, RCSI University of Medicine and Health Sciences; SFI FutureNeuro Research Centre, Dublin 2, Ireland
| | - Hermann Döring
- Division of Molecular Cell Biology, Zoological Institute, Technische Universität Braunschweig; Department of Cell Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Jochen H M Prehn
- RCSI Centre for Systems Medicine and Department of Physiology and Medical Physics, RCSI University of Medicine and Health Sciences; SFI FutureNeuro Research Centre, Dublin 2, Ireland
| | - Klemens Rottner
- Division of Molecular Cell Biology, Zoological Institute, Technische Universität Braunschweig; Department of Cell Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Gregory Giannone
- University Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, Bordeaux, France
| | | | - Dan Ehninger
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.
| | - Dragomir Milovanovic
- German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany.
- Einstein Center for Neuroscience, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Berlin, and Berlin Institute of Health, Berlin, Germany.
| | - Daniele Bano
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.
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Kasianchuk N, Rzymski P, Kaczmarek Ł. The biomedical potential of tardigrade proteins: A review. Biomed Pharmacother 2023; 158:114063. [PMID: 36495665 DOI: 10.1016/j.biopha.2022.114063] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Revised: 11/25/2022] [Accepted: 12/01/2022] [Indexed: 12/12/2022] Open
Abstract
Tardigrades are ubiquitous microinvertebrates exhibiting extreme tolerance to various environmental stressors like low and high temperatures, lack of water, or high radiation. Although exact pathways behind the tardigrade extremotolerance are yet to be elucidated, some molecules involved have been identified. Their evidenced properties may lead to novel opportunities in biomedical and pharmacological development. This review aims to present the general characteristics of tardigrade intrinsically disordered proteins (TDPs: Dsup, CAHS, SAHS, MAHS) and late embryogenesis-abundant proteins (LEA) and provide an updated overview of their features and relevance for potential use in biomedicine and pharmacology. The Dsup reveals a promising action in attenuating oxidative stress, DNA damage, and pyrimidine dimerization, as well as increasing radiotolerance in transfected human cells. Whether Dsup can perform these functions when delivered externally is yet to be understood by in vivo preclinical testing. In turn, CAHS and SAHS demonstrate properties that could benefit the preservation of pharmaceuticals (e.g., vaccines) and biomaterials (e.g., cells). Selected CAHS proteins can also serve as inspiration for designing novel anti-apoptotic agents. The LEA proteins also reveal promising properties to preserve desiccated biomaterials and can act as anti-osmotic agents. In summary, tardigrade molecules reveal several potential biomedical applications advocating further research and development. The challenge of extracting larger amounts of these molecules can be solved with genetic engineering and synthetic biology tools. With new species identified each year and ongoing studies on their extremotolerance, progress in the medical use of tardigrade proteins is expected shortly.
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Affiliation(s)
- Nadiia Kasianchuk
- Department of Animal Taxonomy and Ecology, Faculty of Biology, Adam Mickiewicz University in Poznań, Poznań, Poland; Faculty of Pharmacy, Bogomolets Nationals Medical University, Kyiv, Ukraine.
| | - Piotr Rzymski
- Department of Environmental Medicine, Poznan University of Medical Sciences, Poznan, Poland; Integrated Science Association (ISA), Universal Scientific Education and Research Network (USERN), Poznań, Poland
| | - Łukasz Kaczmarek
- Department of Animal Taxonomy and Ecology, Faculty of Biology, Adam Mickiewicz University in Poznań, Poznań, Poland
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Halma MTJ, Tuszynski JA, Wuite GJL. Optical tweezers for drug discovery. Drug Discov Today 2023; 28:103443. [PMID: 36396117 DOI: 10.1016/j.drudis.2022.103443] [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: 06/26/2022] [Revised: 09/23/2022] [Accepted: 11/09/2022] [Indexed: 11/16/2022]
Abstract
The time taken and the cost of producing novel therapeutic drugs presents a significant burden - a typical target-based drug discovery process involves computational screening of drug libraries, compound assays and expensive clinical trials. This review summarises the value of dynamic conformational information obtained by optical tweezers and how this information can target 'undruggable' proteins. Optical tweezers provide insights into the link between biological mechanisms and structural conformations, which can be used in drug discovery. Developing workflows including software and sample preparation will improve throughput, enabling adoption of optical tweezers in biopharma. As a complementary tool, optical tweezers increase the number of drug candidates, improve the understanding of a target's complex structural dynamics and elucidate interactions between compounds and their targets.
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Affiliation(s)
- Matthew T J Halma
- Department of Physics and Astronomy, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands; LUMICKS B.V, Paalbergweg 3, 1105 AG Amsterdam, The Netherlands
| | - Jack A Tuszynski
- Department of Physics, University of Alberta, 116 St 85 Ave, Edmonton, Alberta T6G 2R3, Canada
| | - Gijs J L Wuite
- Department of Physics and Astronomy, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands.
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5
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Lipiński WP, Visser BS, Robu I, Fakhree MAA, Lindhoud S, Claessens MMAE, Spruijt E. Biomolecular condensates can both accelerate and suppress aggregation of α-synuclein. SCIENCE ADVANCES 2022; 8:eabq6495. [PMID: 36459561 PMCID: PMC10942789 DOI: 10.1126/sciadv.abq6495] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 10/18/2022] [Indexed: 06/17/2023]
Abstract
Biomolecular condensates present in cells can fundamentally affect the aggregation of amyloidogenic proteins and play a role in the regulation of this process. While liquid-liquid phase separation of amyloidogenic proteins by themselves can act as an alternative nucleation pathway, interaction of partly disordered aggregation-prone proteins with preexisting condensates that act as localization centers could be a far more general mechanism of altering their aggregation behavior. Here, we show that so-called host biomolecular condensates can both accelerate and slow down amyloid formation. We study the amyloidogenic protein α-synuclein and two truncated α-synuclein variants in the presence of three types of condensates composed of nonaggregating peptides, RNA, or ATP. Our results demonstrate that condensates can markedly speed up amyloid formation when proteins localize to their interface. However, condensates can also significantly suppress aggregation by sequestering and stabilizing amyloidogenic proteins, thereby providing living cells with a possible protection mechanism against amyloid formation.
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Affiliation(s)
- Wojciech P. Lipiński
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, Netherlands
| | - Brent S. Visser
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, Netherlands
| | - Irina Robu
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, Netherlands
| | - Mohammad A. A. Fakhree
- Nanobiophysics, Faculty of Science and Technology, University of Twente, PO Box 217, 7500 AE Enschede, Netherlands
| | - Saskia Lindhoud
- Department of Molecules and Materials, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, Netherlands
| | - Mireille M. A. E. Claessens
- Nanobiophysics, Faculty of Science and Technology, University of Twente, PO Box 217, 7500 AE Enschede, Netherlands
| | - Evan Spruijt
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, Netherlands
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Berrocal M, Mata AM. The Plasma Membrane Ca 2+-ATPase, a Molecular Target for Tau-induced Cytosolic Calcium Dysregulation. Neuroscience 2022; 518:112-118. [PMID: 35469971 DOI: 10.1016/j.neuroscience.2022.04.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 04/04/2022] [Accepted: 04/18/2022] [Indexed: 11/28/2022]
Abstract
Disruption of calcium (Ca2+) homeostasis is emerging as a prevalent feature of aging and aging-associated neurodegenerative diseases, including Alzheimer's disease (AD), the most common type of tauopathy. This disease is characterized by the combined presence of extracellular neuritic plaques composed by amyloid β-peptides (Aβ) and neurofibrillary tangles of tau. The association of calcium dyshomeostasis with Aβ has been extensively studied, however its link with tau has been less investigated. Thus, this review will concentrate on the functional link between tau and the plasma membrane Ca2+ pump (PMCA) and other membrane proteins involved in the regulation of intracellular calcium and/or its association with neurodegeneration.
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Affiliation(s)
- María Berrocal
- Departamento de Bioquímica y Biología Molecular y Genética, Facultad de Ciencias, Universidad de Extremadura, 06006 Badajoz, Spain; Instituto de Biomarcadores de Patologías Moleculares, Universidad de Extremadura, 06006 Badajoz, Spain
| | - Ana M Mata
- Departamento de Bioquímica y Biología Molecular y Genética, Facultad de Ciencias, Universidad de Extremadura, 06006 Badajoz, Spain; Instituto de Biomarcadores de Patologías Moleculares, Universidad de Extremadura, 06006 Badajoz, Spain.
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7
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Hoffmann C, Sansevrino R, Morabito G, Logan C, Vabulas RM, Ulusoy A, Ganzella M, Milovanovic D. Synapsin Condensates Recruit alpha-Synuclein. J Mol Biol 2021; 433:166961. [PMID: 33774037 DOI: 10.1016/j.jmb.2021.166961] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 03/07/2021] [Accepted: 03/19/2021] [Indexed: 12/24/2022]
Abstract
Neurotransmission relies on the tight spatial and temporal regulation of the synaptic vesicle (SV) cycle. Nerve terminals contain hundreds of SVs that form tight clusters. These clusters represent a distinct liquid phase in which one component of the phase are SVs and the other synapsin 1, a highly abundant synaptic protein. Another major family of disordered proteins at the presynapse includes synucleins, most notably α-synuclein. The precise physiological role of α-synuclein in synaptic physiology remains elusive, albeit its role has been implicated in nearly all steps of the SV cycle. To determine the effect of α-synuclein on the synapsin phase, we employ the reconstitution approach using natively purified SVs from rat brains and the heterologous cell system to generate synapsin condensates. We demonstrate that synapsin condensates recruit α-synuclein, and while enriched into these synapsin condensates, α-synuclein still maintains its high mobility. The presence of SVs enhances the rate of synapsin/α-synuclein condensation, suggesting that SVs act as catalyzers for the formation of synapsin condensates. Notably, at physiological salt and protein concentrations, α-synuclein alone is not able to cluster isolated SVs. Excess of α-synuclein disrupts the kinetics of synapsin/SV condensate formation, indicating that the molar ratio between synapsin and α-synuclein is important in assembling the functional condensates of SVs. Understanding the molecular mechanism of α-synuclein interactions at the nerve terminals is crucial for clarifying the pathogenesis of synucleinopathies, where α-synuclein, synaptic proteins and lipid organelles all accumulate as insoluble intracellular inclusions.
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Affiliation(s)
- Christian Hoffmann
- Laboratory of Molecular Neuroscience, German Center for Neurodegenerative Diseases (DZNE), 10117 Berlin, Germany
| | - Roberto Sansevrino
- Laboratory of Molecular Neuroscience, German Center for Neurodegenerative Diseases (DZNE), 10117 Berlin, Germany
| | - Giuseppe Morabito
- Laboratory of Molecular Neuroscience, German Center for Neurodegenerative Diseases (DZNE), 10117 Berlin, Germany
| | - Chinyere Logan
- Laboratory of Molecular Neuroscience, German Center for Neurodegenerative Diseases (DZNE), 10117 Berlin, Germany
| | - R Martin Vabulas
- Charité - Universitätsmedizin Berlin, Institute of Biochemistry, 10117 Berlin, Germany
| | - Ayse Ulusoy
- Laboratory of Neuroprotective Mechanisms, German Center for Neurodegenerative Diseases (DZNE), 53127 Bonn, Germany
| | - Marcelo Ganzella
- Department of Neurobiology, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany
| | - Dragomir Milovanovic
- Laboratory of Molecular Neuroscience, German Center for Neurodegenerative Diseases (DZNE), 10117 Berlin, Germany.
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8
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Berrocal M, Saez L, Mata AM. Sorcin Activates the Brain PMCA and Blocks the Inhibitory Effects of Molecular Markers of Alzheimer's Disease on the Pump Activity. Int J Mol Sci 2021; 22:ijms22116055. [PMID: 34205207 PMCID: PMC8200006 DOI: 10.3390/ijms22116055] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 05/26/2021] [Accepted: 06/01/2021] [Indexed: 11/16/2022] Open
Abstract
Since dysregulation of intracellular calcium (Ca2+) levels is a common occurrence in neurodegenerative diseases, including Alzheimer’s disease (AD), the study of proteins that can correct neuronal Ca2+ dysregulation is of great interest. In previous work, we have shown that plasma membrane Ca2+-ATPase (PMCA), a high-affinity Ca2+ pump, is functionally impaired in AD and is inhibited by amyloid-β peptide (Aβ) and tau, two key components of pathological AD hallmarks. On the other hand, sorcin is a Ca2+-binding protein highly expressed in the brain, although its mechanism of action is far from being clear. Sorcin has been shown to interact with the intracellular sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA), and other modulators of intracellular Ca2+ signaling, such as the ryanodine receptor or presenilin 2, which is closely associated with AD. The present work focuses on sorcin in search of new regulators of PMCA and antagonists of Aβ and tau toxicity. Results show sorcin as an activator of PMCA, which also prevents the inhibitory effects of Aβ and tau on the pump, and counteracts the neurotoxicity of Aβ and tau by interacting with them.
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9
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Genovese I, Giamogante F, Barazzuol L, Battista T, Fiorillo A, Vicario M, D'Alessandro G, Cipriani R, Limatola C, Rossi D, Sorrentino V, Poser E, Mosca L, Squitieri F, Perluigi M, Arena A, van Petegem F, Tito C, Fazi F, Giorgi C, Calì T, Ilari A, Colotti G. Sorcin is an early marker of neurodegeneration, Ca 2+ dysregulation and endoplasmic reticulum stress associated to neurodegenerative diseases. Cell Death Dis 2020; 11:861. [PMID: 33060591 PMCID: PMC7566454 DOI: 10.1038/s41419-020-03063-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 09/16/2020] [Accepted: 09/18/2020] [Indexed: 12/12/2022]
Abstract
Dysregulation of calcium signaling is emerging as a key feature in the pathogenesis of neurodegenerative diseases such as Alzheimer’s disease (AD), Parkinson’s disease (PD), and Huntington’s disease (HD), and targeting this process may be therapeutically beneficial. Under this perspective, it is important to study proteins that regulate calcium homeostasis in the cell. Sorcin is one of the most expressed calcium-binding proteins in the human brain; its overexpression increases endoplasmic reticulum (ER) calcium concentration and decreases ER stress in the heart and in other cellular types. Sorcin has been hypothesized to be involved in neurodegenerative diseases, since it may counteract the increased cytosolic calcium levels associated with neurodegeneration. In the present work, we show that Sorcin expression levels are strongly increased in cellular, animal, and human models of AD, PD, and HD, vs. normal cells. Sorcin partially colocalizes with RyRs in neurons and microglia cells; functional experiments with microsomes containing high amounts of RyR2 and RyR3, respectively, show that Sorcin is able to regulate these ER calcium channels. The molecular basis of the interaction of Sorcin with RyR2 and RyR3 is demonstrated by SPR. Sorcin also interacts with other ER proteins as SERCA2 and Sigma-1 receptor in a calcium-dependent fashion. We also show that Sorcin regulates ER calcium transients: Sorcin increases the velocity of ER calcium uptake (increasing SERCA activity). The data presented here demonstrate that Sorcin may represent both a novel early marker of neurodegenerative diseases and a response to cellular stress dependent on neurodegeneration.
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Affiliation(s)
- Ilaria Genovese
- Department of Medical Sciences, Laboratory for Technology of Advanced Therapies (LTTA) University of Ferrara, Ferrara, Italy
| | - Flavia Giamogante
- Department of Biomedical Sciences, University of Padova, Padova, Italy.,Padova Neuroscience Center (PNC), University of Padova, Padova, Italy
| | - Lucia Barazzuol
- Department of Biomedical Sciences, University of Padova, Padova, Italy.,Padova Neuroscience Center (PNC), University of Padova, Padova, Italy
| | - Theo Battista
- Department of Biochemical Sciences "A. Rossi Fanelli", University Sapienza of Rome, Rome, Italy
| | - Annarita Fiorillo
- Department of Biochemical Sciences "A. Rossi Fanelli", University Sapienza of Rome, Rome, Italy
| | - Mattia Vicario
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Giuseppina D'Alessandro
- Department of Physiology and Pharmacology, University of Rome "Sapienza", Rome, Italy.,IRCCS Neuromed, Pozzilli, Isernia, Italy
| | - Raffaela Cipriani
- Department of Physiology and Pharmacology, University of Rome "Sapienza", Rome, Italy
| | - Cristina Limatola
- IRCCS Neuromed, Pozzilli, Isernia, Italy.,Department of Physiology and Pharmacology, Sapienza University, Laboratory Affiliated to Istituto Pasteur Italia - Rome, Rome, Italy
| | - Daniela Rossi
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Vincenzo Sorrentino
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Elena Poser
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Luciana Mosca
- Department of Biochemical Sciences "A. Rossi Fanelli", University Sapienza of Rome, Rome, Italy
| | - Ferdinando Squitieri
- Huntington's and Rare Diseases Unit, IRCCS Ospedale Casa Sollievo della Sofferenza, Rome, Italy
| | - Marzia Perluigi
- Department of Biochemical Sciences "A. Rossi Fanelli", University Sapienza of Rome, Rome, Italy
| | - Andrea Arena
- Department of Biochemical Sciences "A. Rossi Fanelli", University Sapienza of Rome, Rome, Italy
| | - Filip van Petegem
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of British Columbia, Vancouver, Canada
| | - Claudia Tito
- Department of Anatomical, Histological, Forensic & Orthopedic Sciences, Section of Histology & Medical Embryology, Sapienza University of Rome, Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Rome, Italy
| | - Francesco Fazi
- Department of Anatomical, Histological, Forensic & Orthopedic Sciences, Section of Histology & Medical Embryology, Sapienza University of Rome, Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Rome, Italy
| | - Carlotta Giorgi
- Department of Medical Sciences, Laboratory for Technology of Advanced Therapies (LTTA) University of Ferrara, Ferrara, Italy
| | - Tito Calì
- Department of Biomedical Sciences, University of Padova, Padova, Italy.,Padova Neuroscience Center (PNC), University of Padova, Padova, Italy
| | - Andrea Ilari
- Institute of Molecular Biology and Pathology, Italian National Research Council, IBPM-CNR, Rome, Italy.
| | - Gianni Colotti
- Institute of Molecular Biology and Pathology, Italian National Research Council, IBPM-CNR, Rome, Italy.
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10
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The potential mechanism of action of Sorcin and its interacting proteins. Clin Chim Acta 2020; 510:741-745. [PMID: 32946798 DOI: 10.1016/j.cca.2020.09.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 09/09/2020] [Accepted: 09/09/2020] [Indexed: 12/14/2022]
Abstract
Sorcin (Soluble resistance-related calcium binding protein) is a calcium binding oncoprotein. Sorcin is overexpressed in several human tumors and cancer cells lines which confers multidrug resistance (MDR) to these cells. This review summarizes the biochemical functions of Sorcin which includes modulation of calcium homeostasis, apoptosis, and cancer metastasis. Sorcin is involved in various biological processes by interacting with other proteins, such as p-glycoprotein, programmed cell death protein 6, tumor necrosis factor receptor-associated protein 1, Annexin A7, polo-like kinase 1, HCV nonstructural 5A, signal transducer and activator of transcription 3, presenilin 2, α-synuclein, Ca2+-release channel and others. A deeper look into the function and interacting partners of Sorcin sheds more light on the possible effects of its physical activity and more elaborately, exploring the role of Sorcin in future research prospects.
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11
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Landeck N, Strathearn KE, Ysselstein D, Buck K, Dutta S, Banerjee S, Lv Z, Hulleman JD, Hindupur J, Lin LK, Padalkar S, Stanciu LA, Lyubchenko YL, Kirik D, Rochet JC. Two C-terminal sequence variations determine differential neurotoxicity between human and mouse α-synuclein. Mol Neurodegener 2020; 15:49. [PMID: 32900375 PMCID: PMC7487555 DOI: 10.1186/s13024-020-00380-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 05/18/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND α-Synuclein (aSyn) aggregation is thought to play a central role in neurodegenerative disorders termed synucleinopathies, including Parkinson's disease (PD). Mouse aSyn contains a threonine residue at position 53 that mimics the human familial PD substitution A53T, yet in contrast to A53T patients, mice show no evidence of aSyn neuropathology even after aging. Here, we studied the neurotoxicity of human A53T, mouse aSyn, and various human-mouse chimeras in cellular and in vivo models, as well as their biochemical properties relevant to aSyn pathobiology. METHODS Primary midbrain cultures transduced with aSyn-encoding adenoviruses were analyzed immunocytochemically to determine relative dopaminergic neuron viability. Brain sections prepared from rats injected intranigrally with aSyn-encoding adeno-associated viruses were analyzed immunohistochemically to determine nigral dopaminergic neuron viability and striatal dopaminergic terminal density. Recombinant aSyn variants were characterized in terms of fibrillization rates by measuring thioflavin T fluorescence, fibril morphologies via electron microscopy and atomic force microscopy, and protein-lipid interactions by monitoring membrane-induced aSyn aggregation and aSyn-mediated vesicle disruption. Statistical tests consisted of ANOVA followed by Tukey's multiple comparisons post hoc test and the Kruskal-Wallis test followed by a Dunn's multiple comparisons test or a two-tailed Mann-Whitney test. RESULTS Mouse aSyn was less neurotoxic than human aSyn A53T in cell culture and in rat midbrain, and data obtained for the chimeric variants indicated that the human-to-mouse substitutions D121G and N122S were at least partially responsible for this decrease in neurotoxicity. Human aSyn A53T and a chimeric variant with the human residues D and N at positions 121 and 122 (respectively) showed a greater propensity to undergo membrane-induced aggregation and to elicit vesicle disruption. Differences in neurotoxicity among the human, mouse, and chimeric aSyn variants correlated weakly with differences in fibrillization rate or fibril morphology. CONCLUSIONS Mouse aSyn is less neurotoxic than the human A53T variant as a result of inhibitory effects of two C-terminal amino acid substitutions on membrane-induced aSyn aggregation and aSyn-mediated vesicle permeabilization. Our findings highlight the importance of membrane-induced self-assembly in aSyn neurotoxicity and suggest that inhibiting this process by targeting the C-terminal domain could slow neurodegeneration in PD and other synucleinopathy disorders.
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Affiliation(s)
- Natalie Landeck
- Brain Repair and Imaging in Neural Systems, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Katherine E. Strathearn
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN USA
- Present address: Fujifilm Irvine Scientific, Santa Ana, CA USA
| | - Daniel Ysselstein
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN USA
- Present address: Northwestern University Feinberg School of Medicine, Chicago, IL USA
| | - Kerstin Buck
- Brain Repair and Imaging in Neural Systems, Department of Experimental Medical Science, Lund University, Lund, Sweden
- Present address: AbbVie Deutschland GmbH & Co KG, Ludwigshafen, Germany
| | - Sayan Dutta
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN USA
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN USA
| | - Siddhartha Banerjee
- Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha, NE USA
| | - Zhengjian Lv
- Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha, NE USA
- Present address: Bruker Nanosurfaces Division, Goleta, Santa Barbara, CA USA
| | - John D. Hulleman
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN USA
- Present address: Departments of Ophthalmology and Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX USA
| | - Jagadish Hindupur
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN USA
- Present address: Liveon Biolabs Pvt. Ltd., Tumakuru, Karnataka India
| | - Li-Kai Lin
- School of Materials Engineering, Purdue University, West Lafayette, IN USA
| | - Sonal Padalkar
- School of Materials Engineering, Purdue University, West Lafayette, IN USA
- Present address: Department of Mechanical Engineering, Iowa State University, Ames, IA USA
| | - Lia A. Stanciu
- School of Materials Engineering, Purdue University, West Lafayette, IN USA
| | - Yuri L. Lyubchenko
- Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha, NE USA
| | - Deniz Kirik
- Brain Repair and Imaging in Neural Systems, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Jean-Christophe Rochet
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN USA
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN USA
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12
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Advances in modelling alpha-synuclein-induced Parkinson’s diseases in rodents: Virus-based models versus inoculation of exogenous preformed toxic species. J Neurosci Methods 2020; 338:108685. [DOI: 10.1016/j.jneumeth.2020.108685] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 03/05/2020] [Accepted: 03/10/2020] [Indexed: 11/22/2022]
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13
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Battista T, Fiorillo A, Chiarini V, Genovese I, Ilari A, Colotti G. Roles of Sorcin in Drug Resistance in Cancer: One Protein, Many Mechanisms, for a Novel Potential Anticancer Drug Target. Cancers (Basel) 2020; 12:cancers12040887. [PMID: 32268494 PMCID: PMC7226229 DOI: 10.3390/cancers12040887] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 03/31/2020] [Accepted: 04/03/2020] [Indexed: 02/07/2023] Open
Abstract
The development of drug resistance is one of the main causes of failure in anti-cancer treatments. Tumor cells adopt many strategies to counteract the action of chemotherapeutic agents, e.g., enhanced DNA damage repair, inactivation of apoptotic pathways, alteration of drug targets, drug inactivation, and overexpression of ABC (Adenosine triphosphate-binding cassette, or ATP-binding cassette) transporters. These are broad substrate-specificity ATP-dependent efflux pumps able to export toxins or drugs out of cells; for instance, ABCB1 (MDR1, or P-glycoprotein 1), overexpressed in most cancer cells, confers them multidrug resistance (MDR). The gene coding for sorcin (SOluble Resistance-related Calcium-binding proteIN) is highly conserved among mammals and is located in the same chromosomal locus and amplicon as the ABC transporters ABCB1 and ABCB4, both in human and rodent genomes (two variants of ABCB1, i.e., ABCB1a and ABCB1b, are in rodent amplicon). Sorcin was initially characterized as a soluble protein overexpressed in multidrug (MD) resistant cells and named "resistance-related" because of its co-amplification with ABCB1. Although for years sorcin overexpression was thought to be only a by-product of the co-amplification with ABC transporter genes, many papers have recently demonstrated that sorcin plays an important part in MDR, indicating a possible role of sorcin as an oncoprotein. The present review illustrates sorcin roles in the generation of MDR via many mechanisms and points to sorcin as a novel potential target of different anticancer molecules.
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Affiliation(s)
- Theo Battista
- Department of Biochemical Sciences, Sapienza University, P.le A.Moro 5, 00185 Rome, Italy; (T.B.); (A.F.)
| | - Annarita Fiorillo
- Department of Biochemical Sciences, Sapienza University, P.le A.Moro 5, 00185 Rome, Italy; (T.B.); (A.F.)
| | - Valerio Chiarini
- Doctoral Programme in Integrative Life Science, Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland;
| | - Ilaria Genovese
- Department of Medical Sciences, Laboratory for Technologies of Advanced Therapies, University of Ferrara, 44121 Ferrara, Italy;
| | - Andrea Ilari
- Institute of Molecular Biology and Pathology, Italian National Research Council, Istituto di Biologia e Patologia Molecolari, Consiglio Nazionale delle Ricerche (IBPM-CNR), c/o Department of Biochemical Sciences, Sapienza University, P.le A.Moro 5, 00185 Rome, Italy
- Correspondence: (A.I.); (G.C.)
| | - Gianni Colotti
- Institute of Molecular Biology and Pathology, Italian National Research Council, Istituto di Biologia e Patologia Molecolari, Consiglio Nazionale delle Ricerche (IBPM-CNR), c/o Department of Biochemical Sciences, Sapienza University, P.le A.Moro 5, 00185 Rome, Italy
- Correspondence: (A.I.); (G.C.)
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Teil M, Arotcarena ML, Faggiani E, Laferriere F, Bezard E, Dehay B. Targeting α-synuclein for PD Therapeutics: A Pursuit on All Fronts. Biomolecules 2020; 10:biom10030391. [PMID: 32138193 PMCID: PMC7175302 DOI: 10.3390/biom10030391] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 02/26/2020] [Accepted: 02/29/2020] [Indexed: 12/15/2022] Open
Abstract
Parkinson's Disease (PD) is characterized both by the loss of dopaminergic neurons in the substantia nigra and the presence of cytoplasmic inclusions called Lewy Bodies. These Lewy Bodies contain the aggregated α-synuclein (α-syn) protein, which has been shown to be able to propagate from cell to cell and throughout different regions in the brain. Due to its central role in the pathology and the lack of a curative treatment for PD, an increasing number of studies have aimed at targeting this protein for therapeutics. Here, we reviewed and discussed the many different approaches that have been studied to inhibit α-syn accumulation via direct and indirect targeting. These analyses have led to the generation of multiple clinical trials that are either completed or currently active. These clinical trials and the current preclinical studies must still face obstacles ahead, but give hope of finding a therapy for PD with time.
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Affiliation(s)
- Margaux Teil
- Univ. de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France; (M.T.); (M.-L.A.); (E.F.); (F.L.); (E.B.)
- CNRS, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France
| | - Marie-Laure Arotcarena
- Univ. de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France; (M.T.); (M.-L.A.); (E.F.); (F.L.); (E.B.)
- CNRS, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France
| | - Emilie Faggiani
- Univ. de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France; (M.T.); (M.-L.A.); (E.F.); (F.L.); (E.B.)
- CNRS, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France
| | - Florent Laferriere
- Univ. de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France; (M.T.); (M.-L.A.); (E.F.); (F.L.); (E.B.)
- CNRS, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France
| | - Erwan Bezard
- Univ. de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France; (M.T.); (M.-L.A.); (E.F.); (F.L.); (E.B.)
- CNRS, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France
| | - Benjamin Dehay
- Univ. de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France; (M.T.); (M.-L.A.); (E.F.); (F.L.); (E.B.)
- CNRS, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France
- Correspondence:
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15
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Chaudhary H, Fernandes RMF, Gowda V, Claessens MMAE, Furó I, Lendel C. Intrinsically disordered protein as carbon nanotube dispersant: How dynamic interactions lead to excellent colloidal stability. J Colloid Interface Sci 2019; 556:172-179. [PMID: 31445446 DOI: 10.1016/j.jcis.2019.08.050] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 08/12/2019] [Accepted: 08/13/2019] [Indexed: 11/19/2022]
Abstract
The rich pool of protein conformations combined with the dimensions and properties of carbon nanotubes create new possibilities in functional materials and nanomedicine. Here, the intrinsically disordered protein α-synuclein is explored as a dispersant of single-walled carbon nanotubes (SWNTs) in water. We use a range of spectroscopic methods to quantify the amount of dispersed SWNT and to elucidate the binding mode of α-synuclein to SWNT. The dispersion ability of α-synuclein is good even with mild sonication and the obtained dispersion is very stable over time. The whole polypeptide chain is involved in the interaction accompanied by a fraction of the chain changing into a helical structure upon binding. Similar to other dispersants, we observe that only a small fraction (15-20%) of α-synuclein is adsorbed on the SWNT surface with an average residence time below 10 ms.
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Affiliation(s)
- Himanshu Chaudhary
- Department of Chemistry, Division of Applied Physical Chemistry, KTH Royal Institute of Technology, SE-10044 Stockholm, Sweden.
| | - Ricardo M F Fernandes
- Department of Chemistry, Division of Applied Physical Chemistry, KTH Royal Institute of Technology, SE-10044 Stockholm, Sweden; Centro de Investigação em Química, Department of Chemistry and Biochemistry, Faculty of Science, University of Porto, Rua do Campo Alegre, s/n, P-4169-007 Porto, Portugal.
| | - Vasantha Gowda
- Department of Chemistry, Division of Applied Physical Chemistry, KTH Royal Institute of Technology, SE-10044 Stockholm, Sweden
| | - Mireille M A E Claessens
- MESA + Institute for Nanotechnology and Mira Institute for Biomedical Technology and Technical Medicine, University of Twente, 7500AE Enschede, the Netherlands
| | - István Furó
- Department of Chemistry, Division of Applied Physical Chemistry, KTH Royal Institute of Technology, SE-10044 Stockholm, Sweden
| | - Christofer Lendel
- Department of Chemistry, Division of Applied Physical Chemistry, KTH Royal Institute of Technology, SE-10044 Stockholm, Sweden.
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16
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Living in Promiscuity: The Multiple Partners of Alpha-Synuclein at the Synapse in Physiology and Pathology. Int J Mol Sci 2019; 20:ijms20010141. [PMID: 30609739 PMCID: PMC6337145 DOI: 10.3390/ijms20010141] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 12/24/2018] [Accepted: 12/26/2018] [Indexed: 12/18/2022] Open
Abstract
Alpha-synuclein (α-syn) is a small protein that, in neurons, localizes predominantly to presynaptic terminals. Due to elevated conformational plasticity, which can be affected by environmental factors, in addition to undergoing disorder-to-order transition upon interaction with different interactants, α-syn is counted among the intrinsically disordered proteins (IDPs) family. As with many other IDPs, α-syn is considered a hub protein. This function is particularly relevant at synaptic sites, where α-syn is abundant and interacts with many partners, such as monoamine transporters, cytoskeletal components, lipid membranes, chaperones and synaptic vesicles (SV)-associated proteins. These protein–protein and protein–lipid membrane interactions are crucial for synaptic functional homeostasis, and alterations in α-syn can cause disruption of this complex network, and thus a failure of the synaptic machinery. Alterations of the synaptic environment or post-translational modification of α-syn can induce its misfolding, resulting in the formation of oligomers or fibrillary aggregates. These α-syn species are thought to play a pathological role in neurodegenerative disorders with α-syn deposits such as Parkinson’s disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA), which are referred to as synucleinopathies. Here, we aim at revising the complex and promiscuous role of α-syn at synaptic terminals in order to decipher whether α-syn molecular interactants may influence its conformational state, contributing to its aggregation, or whether they are just affected by it.
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17
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Martin EM, Jackson MP, Gamerdinger M, Gense K, Karamonos TK, Humes JR, Deuerling E, Ashcroft AE, Radford SE. Conformational flexibility within the nascent polypeptide-associated complex enables its interactions with structurally diverse client proteins. J Biol Chem 2018; 293:8554-8568. [PMID: 29650757 PMCID: PMC5986199 DOI: 10.1074/jbc.ra117.001568] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 04/07/2018] [Indexed: 12/12/2022] Open
Abstract
As newly synthesized polypeptides emerge from the ribosome, it is crucial that they fold correctly. To prevent premature aggregation, nascent chains interact with chaperones that facilitate folding or prevent misfolding until protein synthesis is complete. Nascent polypeptide-associated complex (NAC) is a ribosome-associated chaperone that is important for protein homeostasis. However, how NAC binds its substrates remains unclear. Using native electrospray ionization MS (ESI-MS), limited proteolysis, NMR, and cross-linking, we analyzed the conformational properties of NAC from Caenorhabditis elegans and studied its ability to bind proteins in different conformational states. Our results revealed that NAC adopts an array of compact and expanded conformations and binds weakly to client proteins that are unfolded, folded, or intrinsically disordered, suggestive of broad substrate compatibility. Of note, we found that this weak binding retards aggregation of the intrinsically disordered protein α-synuclein both in vitro and in vivo These findings provide critical insights into the structure and function of NAC. Specifically, they reveal the ability of NAC to exploit its conformational plasticity to bind a repertoire of substrates with unrelated sequences and structures, independently of actively translating ribosomes.
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Affiliation(s)
- Esther M Martin
- From the Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom and
| | - Matthew P Jackson
- From the Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom and
| | - Martin Gamerdinger
- the Department of Biology, Institute of Molecular Microbiology, University of Konstanz, 78454 Konstanz, Germany
| | - Karina Gense
- the Department of Biology, Institute of Molecular Microbiology, University of Konstanz, 78454 Konstanz, Germany
| | - Theodoros K Karamonos
- From the Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom and
| | - Julia R Humes
- From the Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom and
| | - Elke Deuerling
- the Department of Biology, Institute of Molecular Microbiology, University of Konstanz, 78454 Konstanz, Germany
| | - Alison E Ashcroft
- From the Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom and
| | - Sheena E Radford
- From the Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom and
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18
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Collins DW, Gudiseva HV, Chavali VRM, Trachtman B, Ramakrishnan M, Merritt WT, Pistilli M, Rossi RA, Blachon S, Sankar PS, Miller-Ellis E, Lehman A, Addis V, O'Brien JM. The MT-CO1 V83I Polymorphism is a Risk Factor for Primary Open-Angle Glaucoma in African American Men. Invest Ophthalmol Vis Sci 2018; 59:1751-1759. [PMID: 29610859 PMCID: PMC5886029 DOI: 10.1167/iovs.17-23277] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 02/23/2018] [Indexed: 01/05/2023] Open
Abstract
Purpose We investigate the function of the V83I polymorphism (m.6150G>A, rs879053914) in the mitochondrial cytochrome c oxidase subunit 1 (MT-CO1) gene and its role in African American (AA) primary open-angle glaucoma (POAG). Methods This study used Sanger sequencing (1339 cases, 850 controls), phenotypic characterization of Primary Open-Angle African American Glaucoma Genetics study (POAAGG) cases, a masked chart review of CO1 missense cases (V83I plus M117T, n = 29) versus wild type cases (n = 29), a yeast 2-hybrid (Y2H) cDNA library screen, and quantification of protein-protein interactions by Y2H and ELISA. Results The association of V83I with POAG in AA was highly significant for men (odds ratio [OR] 6.5; 95% confidence interval [CI] 2.0-21.3, P = 0.0001), but not for women (OR 1.1; 95% CI, 0.62-2.00, P = 0.78). POAG cases having CO1 double missense mutation (V83I + M117T, L1c2 haplogroup) had a higher cup-to-disc ratio (0.77 vs. 0.71, P = 0.04) and significantly worse visual function (average pattern standard deviation, 6.5 vs. 4.3, P = 0.009; average mean deviation -10.4 vs. -4.5, P = 0.006) when compared to matched wild type cases (L1b haplogroup). Interaction of the V83I region of CO1 with amyloid beta peptide (Aβ) was confirmed by ELISA assay, and this interaction was abrogated by V83I. A Y2H screen of an adult human brain cDNA library with the V83 region of CO1 as bait retrieved the UBQLN1 gene. Conclusions The V83I polymorphism was associated strongly with POAG in AA men and disrupts Aβ-binding to CO1. This region also interacts with a neuroprotective protein, UBQLN1.
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Affiliation(s)
- David W. Collins
- Scheie Eye Institute, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Harini V. Gudiseva
- Scheie Eye Institute, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Venkata R. M. Chavali
- Scheie Eye Institute, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Benjamin Trachtman
- Scheie Eye Institute, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Meera Ramakrishnan
- Scheie Eye Institute, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - William T. Merritt
- Scheie Eye Institute, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Maxwell Pistilli
- Scheie Eye Institute, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Rebecca A. Rossi
- Scheie Eye Institute, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | | | - Prithvi S. Sankar
- Scheie Eye Institute, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Eydie Miller-Ellis
- Scheie Eye Institute, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Amanda Lehman
- Scheie Eye Institute, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Victoria Addis
- Scheie Eye Institute, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Joan M. O'Brien
- Scheie Eye Institute, University of Pennsylvania, Philadelphia, Pennsylvania, United States
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Abstract
α-Synuclein is an abundant neuronal protein that is highly enriched in presynaptic nerve terminals. Genetics and neuropathology studies link α-synuclein to Parkinson's disease (PD) and other neurodegenerative disorders. Accumulation of misfolded oligomers and larger aggregates of α-synuclein defines multiple neurodegenerative diseases called synucleinopathies, but the mechanisms by which α-synuclein acts in neurodegeneration are unknown. Moreover, the normal cellular function of α-synuclein remains debated. In this perspective, we review the structural characteristics of α-synuclein, its developmental expression pattern, its cellular and subcellular localization, and its function in neurons. We also discuss recent progress on secretion of α-synuclein, which may contribute to its interneuronal spread in a prion-like fashion, and describe the neurotoxic effects of α-synuclein that are thought to be responsible for its role in neurodegeneration.
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Affiliation(s)
- Jacqueline Burré
- Appel Institute for Alzheimer's Disease Research, Brain and Mind Research Institute, Weill Cornell Medicine, New York, New York 10021
| | - Manu Sharma
- Appel Institute for Alzheimer's Disease Research, Brain and Mind Research Institute, Weill Cornell Medicine, New York, New York 10021
| | - Thomas C Südhof
- Departments of Molecular and Cellular Physiology, Stanford University Medical School, Stanford, California 94305
- Howard Hughes Medical Institute, Stanford University Medical School, Stanford, California 94305
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20
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Silvers R, Colvin MT, Frederick KK, Jacavone AC, Lindquist S, Linse S, Griffin RG. Aggregation and Fibril Structure of Aβ M01-42 and Aβ 1-42. Biochemistry 2017; 56:4850-4859. [PMID: 28792214 PMCID: PMC8254419 DOI: 10.1021/acs.biochem.7b00729] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A mechanistic understanding of Aβ aggregation and high-resolution structures of Aβ fibrils and oligomers are vital to elucidating relevant details of neurodegeneration in Alzheimer's disease, which will facilitate the rational design of diagnostic and therapeutic protocols. The most detailed and reproducible insights into structure and kinetics have been achieved using Aβ peptides produced by recombinant expression, which results in an additional methionine at the N-terminus. While the length of the C-terminus is well established to have a profound impact on the peptide's aggregation propensity, structure, and neurotoxicity, the impact of the N-terminal methionine on the aggregation pathways and structure is unclear. For this reason, we have developed a protocol to produce recombinant Aβ1-42, sans the N-terminal methionine, using an N-terminal small ubiquitin-like modifier-Aβ1-42 fusion protein in reasonable yield, with which we compared aggregation kinetics with AβM01-42 containing the additional methionine residue. The data revealed that Aβ1-42 and AβM01-42 aggregate with similar rates and by the same mechanism, in which the generation of new aggregates is dominated by secondary nucleation of monomers on the surface of fibrils. We also recorded magic angle spinning nuclear magnetic resonance spectra that demonstrated that excellent spectral resolution is maintained with both AβM01-42 and Aβ1-42 and that the chemical shifts are virtually identical in dipolar recoupling experiments that provide information about rigid residues. Collectively, these results indicate that the structure of the fibril core is unaffected by N-terminal methionine. This is consistent with the recent structures of AβM01-42 in which M0 is located at the terminus of a disordered 14-amino acid N-terminal tail.
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Affiliation(s)
- Robert Silvers
- Department of Chemistry and Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States
| | - Michael T Colvin
- Department of Chemistry and Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States
| | - Kendra K Frederick
- Whitehead Institute for Biomedical Research , Nine Cambridge Center, Cambridge, Massachusetts 02142, United States
| | - Angela C Jacavone
- Department of Chemistry and Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States
| | - Susan Lindquist
- Whitehead Institute for Biomedical Research , Nine Cambridge Center, Cambridge, Massachusetts 02142, United States
| | - Sara Linse
- Department of Biochemistry and Structural Biology, Lund University , SE22100 Lund, Sweden
| | - Robert G Griffin
- Department of Chemistry and Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States
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Duce JA, Wong BX, Durham H, Devedjian JC, Smith DP, Devos D. Post translational changes to α-synuclein control iron and dopamine trafficking; a concept for neuron vulnerability in Parkinson's disease. Mol Neurodegener 2017; 12:45. [PMID: 28592304 PMCID: PMC5463308 DOI: 10.1186/s13024-017-0186-8] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 06/02/2017] [Indexed: 12/21/2022] Open
Abstract
Parkinson's disease is a multifactorial neurodegenerative disorder, the aetiology of which remains elusive. The primary clinical feature of progressively impaired motor control is caused by a loss of midbrain substantia nigra dopamine neurons that have a high α-synuclein (α-syn) and iron content. α-Syn is a neuronal protein that is highly modified post-translationally and central to the Lewy body neuropathology of the disease. This review provides an overview of findings on the role post translational modifications to α-syn have in membrane binding and intracellular vesicle trafficking. Furthermore, we propose a concept in which acetylation and phosphorylation of α-syn modulate endocytic import of iron and vesicle transport of dopamine during normal physiology. Disregulated phosphorylation and oxidation of α-syn mediate iron and dopamine dependent oxidative stress through impaired cellular location and increase propensity for α-syn aggregation. The proposition highlights a connection between α-syn, iron and dopamine, three pathological components associated with disease progression in sporadic Parkinson's disease.
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Affiliation(s)
- James A Duce
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, West Yorkshire, UK. .,Oxidation Biology Unit, the Florey Institute of Neuroscience and Mental Health, the University of Melbourne, Parkville, VIC, Australia.
| | - Bruce X Wong
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, West Yorkshire, UK.,Oxidation Biology Unit, the Florey Institute of Neuroscience and Mental Health, the University of Melbourne, Parkville, VIC, Australia
| | - Hannah Durham
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, West Yorkshire, UK
| | | | - David P Smith
- Biomolecular Research Centre, Sheffield Hallam University, Howard Street, Sheffield, UK
| | - David Devos
- Department of Medical Pharmacology, Lille University, INSERM U1171, CHU of Lille, Lille, France
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22
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ARPP-16 Is a Striatal-Enriched Inhibitor of Protein Phosphatase 2A Regulated by Microtubule-Associated Serine/Threonine Kinase 3 (Mast 3 Kinase). J Neurosci 2017; 37:2709-2722. [PMID: 28167675 DOI: 10.1523/jneurosci.4559-15.2017] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 01/20/2017] [Accepted: 01/25/2017] [Indexed: 12/27/2022] Open
Abstract
ARPP-16 (cAMP-regulated phospho-protein of molecular weight 16 kDa) is one of several small acid-soluble proteins highly expressed in medium spiny neurons of striatum that are phosphorylated in response to dopamine acting via D1 receptor/protein kinase A (PKA) signaling. We show here that ARPP-16 is also phosphorylated in vitro and in vivo by microtubule-associated serine/threonine kinase 3 (MAST3 kinase), an enzyme of previously unknown function that is enriched in striatum. We find that ARPP-16 interacts directly with the scaffolding A subunit of the serine/threonine protein phosphatase, PP2A, and that phosphorylation of ARPP-16 at Ser46 by MAST3 kinase converts the protein into a selective inhibitor of B55α- and B56δ-containing heterotrimeric forms of PP2A. Ser46 of ARPP-16 is phosphorylated to a high basal stoichiometry in striatum, suggestive of basal inhibition of PP2A in striatal neurons. In support of this hypothesis, conditional knock-out of ARPP-16 in CaMKIIα::cre/floxed ARPP-16/19 mice results in dephosphorylation of a subset of PP2A substrates including phospho-Thr75-DARPP-32, phospho-T308-Akt, and phospho-T202/Y204-ERK. Conditional knock-out of ARPP-16/19 is associated with increased motivation measured on a progressive ratio schedule of food reinforcement, yet an attenuated locomotor response to acute cocaine. Our previous studies have shown that ARPP-16 is phosphorylated at Ser88 by PKA. Activation of PKA in striatal slices leads to phosphorylation of Ser88, and this is accompanied by marked dephosphorylation of Ser46. Together, these studies suggest that phospho-Ser46-ARPP-16 acts to basally control PP2A in striatal medium spiny neurons but that dopamine acting via PKA inactivates ARPP-16 leading to selective potentiation of PP2A signaling.SIGNIFICANCE STATEMENT We describe a novel mechanism of signal transduction enriched in medium spiny neurons of striatum that likely mediates effects of the neurotransmitter dopamine acting on these cells. We find that the protein ARPP-16, which is highly expressed in striatal medium spiny neurons, acts as a selective inhibitor of certain forms of the serine/threonine protein phosphatase, PP2A, when phosphorylated by the kinase, MAST3. Under basal conditions, ARPP-16 is phosphorylated by MAST3 to a very high stoichiometry. However, the actions of MAST3 are antagonized by dopamine and cAMP-regulated signaling leading to disinhibition of ARPP-16 and increased PP2A action.
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23
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Endosulfine-alpha inhibits membrane-induced α-synuclein aggregation and protects against α-synuclein neurotoxicity. Acta Neuropathol Commun 2017; 5:3. [PMID: 28069058 PMCID: PMC5223451 DOI: 10.1186/s40478-016-0403-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2016] [Accepted: 12/10/2016] [Indexed: 12/21/2022] Open
Abstract
Neuropathological and genetic findings suggest that the presynaptic protein α-synuclein (aSyn) is involved in the pathogenesis of synucleinopathy disorders, including Parkinson’s disease (PD), dementia with Lewy bodies (DLB) and multiple system atrophy. Evidence suggests that the self-assembly of aSyn conformers bound to phospholipid membranes in an aggregation-prone state plays a key role in aSyn neurotoxicity. Accordingly, we hypothesized that protein binding partners of lipid-associated aSyn could inhibit the formation of toxic aSyn oligomers at membrane surfaces. To address this hypothesis, we characterized the protein endosulfine-alpha (ENSA), previously shown to interact selectively with membrane-bound aSyn, in terms of its effects on the membrane-induced aggregation and neurotoxicity of two familial aSyn mutants, A30P and G51D. We found that wild-type ENSA, but not the non-aSyn-binding S109E variant, interfered with membrane-induced aSyn self-assembly, aSyn-mediated vesicle disruption and aSyn neurotoxicity. Immunoblotting analyses revealed that ENSA was down-regulated in the brains of synucleinopathy patients versus non-diseased individuals. Collectively, these results suggest that ENSA can alleviate neurotoxic effects of membrane-bound aSyn via an apparent chaperone-like activity at the membrane surface, and a decrease in ENSA expression may contribute to aSyn neuropathology in synucleinopathy disorders. More generally, our findings suggest that promoting interactions between lipid-bound, amyloidogenic proteins and their binding partners is a viable strategy to alleviate cytotoxicity in a range of protein misfolding disorders.
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24
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Ottolini D, Calí T, Szabò I, Brini M. Alpha-synuclein at the intracellular and the extracellular side: functional and dysfunctional implications. Biol Chem 2017; 398:77-100. [DOI: 10.1515/hsz-2016-0201] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Accepted: 08/01/2016] [Indexed: 12/16/2022]
Abstract
Abstract
Alpha-synuclein (α-syn) is an abundant neuronal protein whose physiological function, even if still not completely understood, has been consistently related to synaptic function and vesicle trafficking. A group of disorders known as synucleinopathies, among which Parkinson’s disease (PD), is deeply associated with the misfolding and aggregation of α-syn, which can give rise to proteinaceous inclusion known as Lewy bodies (LB). Proteostasis stress is a relevant aspect in these diseases and, currently, the presence of oligomeric α-syn species rather than insoluble aggregated forms, appeared to be associated with cytotoxicity. Many observations suggest that α-syn is responsible for neurodegeneration by interfering with multiple signaling pathways. α-syn protein can directly form plasma membrane channels or modify with their activity, thus altering membrane permeability to ions, abnormally associate with mitochondria and cause mitochondrial dysfunction (i.e. mitochondrial depolarization, Ca2+ dys-homeostasis, cytochrome c release) and interfere with autophagy regulation. The picture is further complicated by the fact that single point mutations, duplications and triplication in α-syn gene are linked to autosomal dominant forms of PD. In this review we discuss the multi-faced aspect of α-syn biology and address the main hypothesis at the basis of its involvement in neuronal degeneration.
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25
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Sivanesam K, Andersen NH. Modulating the Amyloidogenesis of α-Synuclein. Curr Neuropharmacol 2016; 14:226-37. [PMID: 26517049 PMCID: PMC4857621 DOI: 10.2174/1570159x13666151030103153] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 05/13/2015] [Accepted: 05/13/2015] [Indexed: 12/16/2022] Open
Abstract
Alpha-Synuclein is found in the neuronal cells but its native function is not well known. While α -synuclein is an intrinsically disordered protein that adopts a helical conformation upon membrane binding, numerous studies have shown that oligomeric β-forms of this protein are cytotoxic. This response to misfolded species contributes to Parkinson's Disease etiology and symptoms. The resulting amyloid fibrils are an established diagnostic in Parkinson's Disease. In this review, we focus on strategies that have been used to inhibit the amyloidogenesis of α -synuclein either by stabilizing the native state, or by redirecting the pathway to less toxic aggregates. Small molecules such as polyphenols, peptides as well as large proteins have proven effective at protecting cells against the cytotoxicity of α-synuclein. These strategies may lead to the development of therapeutic agents that could prove useful in combating this disease.
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Affiliation(s)
| | - Niels H Andersen
- Department of Chemistry, University of Washington, Seattle, WA 98195, USA.
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26
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Chung SY, Kishinevsky S, Mazzulli JR, Graziotto J, Mrejeru A, Mosharov EV, Puspita L, Valiulahi P, Sulzer D, Milner TA, Taldone T, Krainc D, Studer L, Shim JW. Parkin and PINK1 Patient iPSC-Derived Midbrain Dopamine Neurons Exhibit Mitochondrial Dysfunction and α-Synuclein Accumulation. Stem Cell Reports 2016; 7:664-677. [PMID: 27641647 PMCID: PMC5063469 DOI: 10.1016/j.stemcr.2016.08.012] [Citation(s) in RCA: 150] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 08/17/2016] [Accepted: 08/17/2016] [Indexed: 01/29/2023] Open
Abstract
Parkinson's disease (PD) is characterized by the selective loss of dopamine neurons in the substantia nigra; however, the mechanism of neurodegeneration in PD remains unclear. A subset of familial PD is linked to mutations in PARK2 and PINK1, which lead to dysfunctional mitochondria-related proteins Parkin and PINK1, suggesting that pathways implicated in these monogenic forms could play a more general role in PD. We demonstrate that the identification of disease-related phenotypes in PD-patient-specific induced pluripotent stem cell (iPSC)-derived midbrain dopamine (mDA) neurons depends on the type of differentiation protocol utilized. In a floor-plate-based but not a neural-rosette-based directed differentiation strategy, iPSC-derived mDA neurons recapitulate PD phenotypes, including pathogenic protein accumulation, cell-type-specific vulnerability, mitochondrial dysfunction, and abnormal neurotransmitter homeostasis. We propose that these form a pathogenic loop that contributes to disease. Our study illustrates the promise of iPSC technology for examining PD pathogenesis and identifying therapeutic targets.
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Affiliation(s)
- Sun Young Chung
- Center for Stem Cell Biology, Sloan-Kettering Institute, New York, NY 10065, USA; Developmental Biology Program, Sloan-Kettering Institute, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, Box 256, New York, NY 10065, USA
| | - Sarah Kishinevsky
- Center for Stem Cell Biology, Sloan-Kettering Institute, New York, NY 10065, USA; Developmental Biology Program, Sloan-Kettering Institute, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, Box 256, New York, NY 10065, USA
| | - Joseph R Mazzulli
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - John Graziotto
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Ana Mrejeru
- Department of Neurology, Columbia University Medical Center, New York, NY 10032, USA
| | - Eugene V Mosharov
- Department of Neurology, Columbia University Medical Center, New York, NY 10032, USA
| | - Lesly Puspita
- Soonchunhyang Institute of Medi-bio Science (SIMS), Soonchunhyang University, 25, Bongjeong-ro, Dongnam-gu, Cheonan-si 31151, Korea
| | - Parvin Valiulahi
- Soonchunhyang Institute of Medi-bio Science (SIMS), Soonchunhyang University, 25, Bongjeong-ro, Dongnam-gu, Cheonan-si 31151, Korea
| | - David Sulzer
- Department of Neurology, Columbia University Medical Center, New York, NY 10032, USA; Department of Psychiatry, Columbia University Medical Center, New York, NY 10032, USA; Department of Pharmacology, Columbia University Medical Center, New York, NY 10032, USA
| | - Teresa A Milner
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA; Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology, The Rockefeller University, New York, NY 10065, USA
| | - Tony Taldone
- Molecular Pharmacology and Chemistry Program, Sloan-Kettering Institute, New York, NY 10065, USA
| | - Dimitri Krainc
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Lorenz Studer
- Center for Stem Cell Biology, Sloan-Kettering Institute, New York, NY 10065, USA; Developmental Biology Program, Sloan-Kettering Institute, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, Box 256, New York, NY 10065, USA.
| | - Jae-Won Shim
- Soonchunhyang Institute of Medi-bio Science (SIMS), Soonchunhyang University, 25, Bongjeong-ro, Dongnam-gu, Cheonan-si 31151, Korea.
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27
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Kim SI, Lee HJ, Kim SS, Kwon YS, Chun W. Sequestration of sorcin by aberrant forms of tau results in the defective calcium homeostasis. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2016; 20:387-97. [PMID: 27382355 PMCID: PMC4930907 DOI: 10.4196/kjpp.2016.20.4.387] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Revised: 03/23/2016] [Accepted: 04/09/2016] [Indexed: 11/15/2022]
Abstract
Neurofi brillary tangles (NFTs) of microtubule-associated protein tau are a pathological hallmark of Alzheimer's disease (AD). Endoplasmic reticulum (ER) stress has been known to be involved in the pathogenesis of AD. However, the exact role of ER stress in tau pathology has not yet been clearly elucidated. In present study, the possible relationship between tau pathology and ER stress was examined in terms of sorcin, which is a calcium binding protein and plays an important role in calcium homeostasis. Our previous yeast two hybrid study showed that sorcin is a novel tau interacting protein. Caspase-3-cleaved tau (T4C3) showed significantly increased tau-sorcin interaction compared to wild type tau (T4). Thapsigargin-induced ER stress and co-expression of constitutively active GSK3β (GSK3β-S9A) also exhibited significantly increased tau-sorcin interactions. T4C3-expressing cells showed potentiated thapsigargin-induced apoptosis and disruption of intracellular calcium homeostasis compared to T4-expressing cells. Overexpression of sorcin signifi cantly attenuated thapsigargin-induced apoptosis and disruption of calcium homeostasis. In contrary, siRNA-mediated knock-down of sorcin showed significantly increased thapsigargin-induced apoptosis and disruption of calcium homeostasis. These data strongly suggest that sequestration of sorcin by aberrant forms of tau compromises the function of sorcin, such as calcium homeostasis and cellular resistance by ER stress, which may consequently result in the contribution to the progression of AD.
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Affiliation(s)
- Song-In Kim
- Department of Pharmacology, School of Medicine, Kangwon National University, Chuncheon 24341, Korea
| | - Hee Jae Lee
- Department of Pharmacology, School of Medicine, Kangwon National University, Chuncheon 24341, Korea
| | - Sung-Soo Kim
- Department of Pharmacology, School of Medicine, Kangwon National University, Chuncheon 24341, Korea
| | - Yong-Soo Kwon
- School of Pharmacy, Kangwon National University, Chuncheon 24341, Korea
| | - Wanjoo Chun
- Department of Pharmacology, School of Medicine, Kangwon National University, Chuncheon 24341, Korea
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28
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Benskey MJ, Perez RG, Manfredsson FP. The contribution of alpha synuclein to neuronal survival and function - Implications for Parkinson's disease. J Neurochem 2016; 137:331-59. [PMID: 26852372 PMCID: PMC5021132 DOI: 10.1111/jnc.13570] [Citation(s) in RCA: 157] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 01/29/2016] [Indexed: 02/06/2023]
Abstract
The aggregation of alpha synuclein (α-syn) is a neuropathological feature that defines a spectrum of disorders collectively termed synucleinopathies, and of these, Parkinson's disease (PD) is arguably the best characterized. Aggregated α-syn is the primary component of Lewy bodies, the defining pathological feature of PD, while mutations or multiplications in the α-syn gene result in familial PD. The high correlation between α-syn burden and PD has led to the hypothesis that α-syn aggregation produces toxicity through a gain-of-function mechanism. However, α-syn has been implicated to function in a diverse range of essential cellular processes such as the regulation of neurotransmission and response to cellular stress. As such, an alternative hypothesis with equal explanatory power is that the aggregation of α-syn results in toxicity because of a toxic loss of necessary α-syn function, following sequestration of functional forms α-syn into insoluble protein aggregates. Within this review, we will provide an overview of the literature linking α-syn to PD and the knowledge gained from current α-syn-based animal models of PD. We will then interpret these data from the viewpoint of the α-syn loss-of-function hypothesis and provide a potential mechanistic model by which loss of α-syn function could result in at least some of the neurodegeneration observed in PD. By providing an alternative perspective on the etiopathogenesis of PD and synucleinopathies, this may reveal alternative avenues of research in order to identify potential novel therapeutic targets for disease modifying strategies. The correlation between α-synuclein burden and Parkinson's disease pathology has led to the hypothesis that α-synuclein aggregation produces toxicity through a gain-of-function mechanism. However, in this review, we discuss data supporting the alternative hypothesis that the aggregation of α-synuclein results in toxicity because of loss of necessary α-synuclein function at the presynaptic terminal, following sequestration of functional forms of α-synuclein into aggregates.
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Affiliation(s)
- Matthew J Benskey
- Department of Translational Science and Molecular Medicine, College of Human Medicine, Michigan State University, Grand Rapids, Michigan, USA
| | - Ruth G Perez
- Department of Biomedical Sciences, Center of Emphasis in Neuroscience, Paul L. Foster School of Medicine, Texas Tech University of the Health Sciences El Paso, El Paso, Texas, USA
| | - Fredric P Manfredsson
- Department of Translational Science and Molecular Medicine, College of Human Medicine, Michigan State University, Grand Rapids, Michigan, USA
- Hauenstein Neuroscience Center, Mercy Health Saint Mary's, Grand Rapids, Michigan, USA
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29
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Ilie IM, den Otter WK, Briels WJ. A coarse grained protein model with internal degrees of freedom. Application to α-synuclein aggregation. J Chem Phys 2016; 144:085103. [DOI: 10.1063/1.4942115] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Affiliation(s)
- Ioana M. Ilie
- Computational Chemical Physics, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands
- MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Wouter K. den Otter
- Computational Chemical Physics, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands
- MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
- Multi Scale Mechanics, Faculty of Engineering Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Wim J. Briels
- Computational Chemical Physics, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands
- MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
- Forschungszentrum Jülich, ICS, D-52425 Jülich, Germany
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30
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Mor DE, Ugras SE, Daniels MJ, Ischiropoulos H. Dynamic structural flexibility of α-synuclein. Neurobiol Dis 2015; 88:66-74. [PMID: 26747212 DOI: 10.1016/j.nbd.2015.12.018] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 12/21/2015] [Accepted: 12/25/2015] [Indexed: 01/08/2023] Open
Abstract
α-Synuclein is a conserved, abundantly expressed protein that is partially localized in pre-synaptic terminals in the central nervous system. The precise biological function(s) and structure of α-synuclein are under investigation. Recently, the native conformation and the presence of naturally occurring multimeric assemblies have come under debate. These are important deliberations because α-synuclein assembles into highly organized amyloid-like fibrils and non-amyloid amorphous aggregates that constitute the neuronal inclusions in Parkinson's disease and related disorders. Therefore understanding the nature of the native and pathological conformations is pivotal from the standpoint of therapeutic interventions that could maintain α-synuclein in its physiological state. In this review, we will discuss the existing evidence that define the physiological states of α-synuclein and highlight how the inherent structural flexibility of this protein may be important in health and disease.
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Affiliation(s)
- Danielle E Mor
- Biomedical graduate studies in Neuroscience, Raymond and Ruth Perelman School of Medicine at the University of Pennsylvania, PA 19104, United States
| | - Scott E Ugras
- Biomedical graduate studies in Biochemistry and Molecular Biophysics, Raymond and Ruth Perelman School of Medicine at the University of Pennsylvania, PA 19104, United States
| | - Malcolm J Daniels
- Biomedical graduate studies in Pharmacology, Raymond and Ruth Perelman School of Medicine at the University of Pennsylvania, PA 19104, United States
| | - Harry Ischiropoulos
- Biomedical graduate studies in Neuroscience, Raymond and Ruth Perelman School of Medicine at the University of Pennsylvania, PA 19104, United States; Biomedical graduate studies in Biochemistry and Molecular Biophysics, Raymond and Ruth Perelman School of Medicine at the University of Pennsylvania, PA 19104, United States; Biomedical graduate studies in Pharmacology, Raymond and Ruth Perelman School of Medicine at the University of Pennsylvania, PA 19104, United States; Children's Hospital of Philadelphia Research Institute, PA 19104, United States; Department of Pediatrics, Raymond, and Ruth Perelman School of Medicine at the University of Pennsylvania, PA 19104, United States; Department of Systems Pharmacology and Translational Therapeutics, Raymond, and Ruth Perelman School of Medicine at the University of Pennsylvania, PA 19104, United States.
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31
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Structural basis of Sorcin-mediated calcium-dependent signal transduction. Sci Rep 2015; 5:16828. [PMID: 26577048 PMCID: PMC4649501 DOI: 10.1038/srep16828] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Accepted: 10/20/2015] [Indexed: 12/11/2022] Open
Abstract
Sorcin is an essential penta-EF hand calcium binding protein, able to confer the multi-drug resistance phenotype to drug-sensitive cancer cells and to reduce Endoplasmic Reticulum stress and cell death. Sorcin silencing blocks cell cycle progression in mitosis and induces cell death by triggering apoptosis. Sorcin participates in the modulation of calcium homeostasis and in calcium-dependent cell signalling in normal and cancer cells. The molecular basis of Sorcin action is yet unknown. The X-ray structures of Sorcin in the apo (apoSor) and in calcium bound form (CaSor) reveal the structural basis of Sorcin action: calcium binding to the EF1-3 hands promotes a large conformational change, involving a movement of the long D-helix joining the EF1-EF2 sub-domain to EF3 and the opening of EF1. This movement promotes the exposure of a hydrophobic pocket, which can accommodate in CaSor the portion of its N-terminal domain displaying the consensus binding motif identified by phage display experiments. This domain inhibits the interaction of sorcin with PDCD6, a protein that carries the Sorcin consensus motif, co-localizes with Sorcin in the perinuclear region of the cell and in the midbody and is involved in the onset of apoptosis.
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32
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Lin W, insley T, Tuttle MD, Zhu L, Berthold DA, Král P, Rienstra CM, Murphy CJ. Control of protein orientation on gold nanoparticles. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2015; 119:21035-21043. [PMID: 28626495 PMCID: PMC5472360 DOI: 10.1021/acs.jpcc.5b07701] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Gold nanoparticles (Au NPs) have attracted much attention due to their potential applications in nano-medicine. While numerous studies have quantified biomolecular adsorption to Au NPs in terms of equilibrium binding constants, far less is known about biomolecular orientation on nanoparticle surfaces. In this study, the binding of the protein α-synuclein to citrate and (16-mercaptohexadecyl) trimethylammonium bromide (MTAB) coated 12 nm Au NPs is examined by heteronuclear single quantum coherence NMR spectroscopy to provide site-specific measurements of protein-nanoparticle binding. Molecular dynamics simulations support the orientation assignments, which show N-terminus binding to the Au NP for citrate-capped NPs, and C-terminus binding for the MTAB-capped NPs.
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Affiliation(s)
- Wayne Lin
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Matthews Avenue, Urbana, Illinois, 61801, USA
| | - Thomas insley
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois, 60607, USA
| | - Marcus D. Tuttle
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Matthews Avenue, Urbana, Illinois, 61801, USA
| | - Lingyang Zhu
- School of Chemical Sciences, University of Illinois at Urbana-Champaign, 505 South Matthews Avenue, Urbana, Illinois, 61801, USA
| | - Deborah A. Berthold
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Matthews Avenue, Urbana, Illinois, 61801, USA
| | - Petr Král
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois, 60607, USA
- Department of Physics, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois, 60607, USA
| | - Chad M. Rienstra
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Matthews Avenue, Urbana, Illinois, 61801, USA
- Department of Biochemistry, University of Illinois at Urbana-Champaign, 600 South Matthews Avenue, Urbana, Illinois, 61801, USA
- Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, 607 South Matthews Avenue, Urbana, Illinois, 61801, USA
| | - Catherine J. Murphy
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Matthews Avenue, Urbana, Illinois, 61801, USA
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Colvin MT, Silvers R, Frohm B, Su Y, Linse S, Griffin RG. High resolution structural characterization of Aβ42 amyloid fibrils by magic angle spinning NMR. J Am Chem Soc 2015; 137:7509-18. [PMID: 26001057 PMCID: PMC4623963 DOI: 10.1021/jacs.5b03997] [Citation(s) in RCA: 88] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
![]()
The presence of amyloid plaques composed
of amyloid beta (Aβ)
fibrils is a hallmark of Alzheimer’s disease (AD). The Aβ
peptide is present as several length variants with two common alloforms
consisting of 40 and 42 amino acids, denoted Aβ1–40 and Aβ1–42, respectively. While there have
been numerous reports that structurally characterize fibrils of Aβ1–40, very little is known about the structure of amyloid
fibrils of Aβ1–42, which are considered the
more toxic alloform involved in AD. We have prepared isotopically 13C/15N labeled AβM01–42 fibrils in vitro from recombinant protein and examined their 13C–13C and 13C–15N magic angle spinning (MAS) NMR spectra. In contrast to several
other studies of Aβ fibrils, we observe spectra with excellent
resolution and a single set of chemical shifts, suggesting the presence
of a single fibril morphology. We report the initial structural characterization
of AβM01–42 fibrils utilizing 13C and 15N shift assignments of 38 of the 43 residues,
including the backbone and side chains, obtained through a series
of cross-polarization based 2D and 3D 13C–13C, 13C–15N MAS NMR experiments for rigid
residues along with J-based 2D TOBSY experiments for dynamic residues.
We find that the first ∼5 residues are dynamic and most efficiently
detected in a J-based TOBSY spectrum. In contrast, residues 16–42
are easily observed in cross-polarization experiments and most likely
form the amyloid core. Calculation of ψ and φ dihedral
angles from the chemical shift assignments indicate that 4 β-strands
are present in the fibril’s secondary structure.
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Affiliation(s)
- Michael T Colvin
- †Department of Chemistry and Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Robert Silvers
- †Department of Chemistry and Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Birgitta Frohm
- ‡Department of Biochemistry and Structural Biology, Lund University, SE22100 Lund, Sweden
| | - Yongchao Su
- †Department of Chemistry and Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Sara Linse
- ‡Department of Biochemistry and Structural Biology, Lund University, SE22100 Lund, Sweden
| | - Robert G Griffin
- †Department of Chemistry and Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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Sivanesam K, Byrne A, Bisaglia M, Bubacco L, Andersen N. Binding Interactions of Agents That Alter α-Synuclein Aggregation. RSC Adv 2015; 5:11577-11590. [PMID: 25705374 DOI: 10.1039/c5ra00325c] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Further examination of peptides with well-folded antiparallel β strands as inhibitors of amyloid formation from α-synuclein has resulted in more potent inhibitors. Several of these had multiple Tyr residues and represent a new lead for inhibitor design by small peptides that do not divert α-synuclein to non-amyloid aggregate formation. The most potent inhibitor obtained in this study is a backbone cyclized version of a previously studied β hairpin, designated as WW2, with a cross-strand Trp/Trp cluster. The cyclization was accomplished by adding a d-Pro-l-Pro turn locus across strand termini. At a 2:1 peptide to α-synuclein ratio, cyclo-WW2 displays complete inhibition of β-structure formation. Trp-bearing antiparallel β-sheets held together by a disulphide bond are also potent inhibitors. 15N HSQC spectra of α-synuclein provided new mechanistic details. The time course of 15N HSQC spectral changes observed during β-oligomer formation has revealed which segments of the structure become part of the rigid core of an oligomer at early stages of amyloidogenesis and that the C-terminus remains fully flexible throughout the process. All of the effective peptide inhibitors display binding-associated titration shifts in 15N HSQC spectra of α-synuclein in the C-terminal Q109-E137 segment. Cyclo-WW2, the most potent inhibitor, also displays titration shifts in the G41-T54 span of α-synuclein, an additional binding site. The earliest aggregation event appears to be centered about H50 which is also a binding site for our most potent inhibitor.
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Affiliation(s)
- K Sivanesam
- Department of Chemistry, University of Washington, Seattle, WA 98195
| | - A Byrne
- Department of Chemistry, University of Washington, Seattle, WA 98195
| | - M Bisaglia
- Department of Biology, University of Padua, 35121 Padova, Italy
| | - L Bubacco
- Department of Biology, University of Padua, 35121 Padova, Italy
| | - N Andersen
- Department of Chemistry, University of Washington, Seattle, WA 98195
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Snead D, Eliezer D. Alpha-synuclein function and dysfunction on cellular membranes. Exp Neurobiol 2014; 23:292-313. [PMID: 25548530 PMCID: PMC4276801 DOI: 10.5607/en.2014.23.4.292] [Citation(s) in RCA: 155] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 11/15/2014] [Accepted: 11/16/2014] [Indexed: 11/19/2022] Open
Abstract
Alpha-synuclein is a small neuronal protein that is closely associated with the etiology of Parkinson's disease. Mutations in and alterations in expression levels of alpha-synuclein cause autosomal dominant early onset heredity forms of Parkinson's disease, and sporadic Parkinson's disease is defined in part by the presence of Lewy bodies and Lewy neurites that are composed primarily of alpha-synuclein deposited in an aggregated amyloid fibril state. The normal function of alpha-synuclein is poorly understood, and the precise mechanisms by which it leads to toxicity and cell death are also unclear. Although alpha-synuclein is a highly soluble, cytoplasmic protein, it binds to a variety of cellular membranes of different properties and compositions. These interactions are considered critical for at least some normal functions of alpha-synuclein, and may well play critical roles in both the aggregation of the protein and its mechanisms of toxicity. Here we review the known features of alpha-synuclein membrane interactions in the context of both the putative functions of the protein and of its pathological roles in disease.
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Affiliation(s)
- David Snead
- Department of Biochemistry, Weill Cornell Medical College, New York, NY 10065, USA
| | - David Eliezer
- Department of Biochemistry, Weill Cornell Medical College, New York, NY 10065, USA
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Abstract
Genetic and pathological studies link α-synuclein to the etiology of Parkinson's disease (PD), but the normal function of this presynaptic protein remains unknown. α-Synuclein, an acidic lipid binding protein, shares high sequence identity with β- and γ-synuclein. Previous studies have implicated synucleins in synaptic vesicle (SV) trafficking, although the precise site of synuclein action continues to be unclear. Here we show, using optical imaging, electron microscopy, and slice electrophysiology, that synucleins are required for the fast kinetics of SV endocytosis. Slowed endocytosis observed in synuclein null cultures can be rescued by individually expressing mouse α-, β-, or γ-synuclein, indicating they are functionally redundant. Through comparisons to dynamin knock-out synapses and biochemical experiments, we suggest that synucleins act at early steps of SV endocytosis. Our results categorize α-synuclein with other familial PD genes known to regulate SV endocytosis, implicating this pathway in PD.
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37
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Colotti G, Poser E, Fiorillo A, Genovese I, Chiarini V, Ilari A. Sorcin, a calcium binding protein involved in the multidrug resistance mechanisms in cancer cells. Molecules 2014; 19:13976-89. [PMID: 25197934 PMCID: PMC6271628 DOI: 10.3390/molecules190913976] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Revised: 08/27/2014] [Accepted: 08/28/2014] [Indexed: 11/23/2022] Open
Abstract
Sorcin is a penta-EF hand calcium binding protein, which participates in the regulation of calcium homeostasis in cells. Sorcin regulates calcium channels and exchangers located at the plasma membrane and at the endo/sarcoplasmic reticulum (ER/SR), and allows high levels of calcium in the ER to be maintained, preventing ER stress and possibly, the unfolded protein response. Sorcin is highly expressed in the heart and in the brain, and overexpressed in many cancer cells. Sorcin gene is in the same amplicon as other genes involved in the resistance to chemotherapeutics in cancer cells (multi-drug resistance, MDR) such as ABCB4 and ABCB1; its overexpression results in increased drug resistance to a number of chemotherapeutic agents, and inhibition of sorcin expression by sorcin-targeting RNA interference leads to reversal of drug resistance. Sorcin is increasingly considered a useful marker of MDR and may represent a therapeutic target for reversing tumor multidrug resistance.
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Affiliation(s)
- Gianni Colotti
- Institute of Biology, Molecular Medicine and Nanobiotechnology, Consiglio Nazionale delle Ricerche, P.le A Moro 5, Rome 00185, Italy.
| | - Elena Poser
- Department Biochemical Sciences "A. Rossi Fanelli", University Sapienza, P.le A. Moro 5, Rome 00185, Italy.
| | - Annarita Fiorillo
- Department Biochemical Sciences "A. Rossi Fanelli", University Sapienza, P.le A. Moro 5, Rome 00185, Italy.
| | - Ilaria Genovese
- Department Biochemical Sciences "A. Rossi Fanelli", University Sapienza, P.le A. Moro 5, Rome 00185, Italy.
| | - Valerio Chiarini
- Department Biochemical Sciences "A. Rossi Fanelli", University Sapienza, P.le A. Moro 5, Rome 00185, Italy.
| | - Andrea Ilari
- Institute of Biology, Molecular Medicine and Nanobiotechnology, Consiglio Nazionale delle Ricerche, P.le A Moro 5, Rome 00185, Italy.
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Kanaan NM, Manfredsson FP. Loss of functional alpha-synuclein: a toxic event in Parkinson's disease? JOURNAL OF PARKINSONS DISEASE 2014; 2:249-67. [PMID: 23938255 PMCID: PMC4736738 DOI: 10.3233/jpd-012138] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The discovery that alpha-synuclein (α-syn) is the primary component of the neuropathological hallmarks of Parkinson's disease (PD) and the identification of α-syn mutations in numerous inherited forms of PD has positioned α-syn at the top of the list of important factors in the pathogenesis of PD. Based on the pathological accumulation of α-syn in the brains of patients, the field is currently focused on therapeutic strategies that aim to reduce or eliminate α-syn. However, recent evidence suggests α-syn is a critical protein in neuron (i.e. dopamine neurons) survival and that maintaining a certain level of biologically functional α-syn is an important consideration in targeting α-syn for therapies. Despite the widespread interest in α-syn, the normal biological functions remain elusive, but a large body of work is focused on addressing this issue. In this review, we will discuss the current evidence related to α-syn function, α-syn folding and aggregation, and α-syn's role in disease. Finally, we will propose a relatively novel hypothesis on the pathogenesis of PD that hinges upon the premises that functional α-syn is critical to cell survival and that a reduction in biologically functional α-syn, whether through aggregation or reduced expression, may lead to the neurodegeneration in PD.
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Affiliation(s)
- Nicholas M Kanaan
- Department of Translational Science & Molecular Medicine, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503, USA
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39
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Gould N, Mor DE, Lightfoot R, Malkus K, Giasson B, Ischiropoulos H. Evidence of native α-synuclein conformers in the human brain. J Biol Chem 2014; 289:7929-34. [PMID: 24474688 DOI: 10.1074/jbc.c113.538249] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
α-Synuclein aggregation is central to the pathogenesis of several brain disorders. However, the native conformations and functions of this protein in the human brain are not precisely known. The native state of α-synuclein was probed by gel filtration coupled with native gradient gel separation, an array of antibodies with non-overlapping epitopes, and mass spectrometry. The existence of metastable conformers and stable monomer was revealed in the human brain.
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Affiliation(s)
- Neal Gould
- From the Departments of Pediatrics and Pharmacology, The Children's Hospital of Philadelphia Research Institute and
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40
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Abstract
Human genetics has indicated a causal role for the protein α-synuclein in the pathogenesis of familial Parkinson's disease (PD), and the aggregation of synuclein in essentially all patients with PD suggests a central role for this protein in the sporadic disorder. Indeed, the accumulation of misfolded α-synuclein now defines multiple forms of neural degeneration. Like many of the proteins that accumulate in other neurodegenerative disorders, however, the normal function of synuclein remains poorly understood. In this article, we review the role of synuclein at the nerve terminal and in membrane remodeling. We also consider the prion-like propagation of misfolded synuclein as a mechanism for the spread of degeneration through the neuraxis.
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41
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Ageta-Ishihara N, Yamakado H, Morita T, Hattori S, Takao K, Miyakawa T, Takahashi R, Kinoshita M. Chronic overload of SEPT4, a parkin substrate that aggregates in Parkinson's disease, causes behavioral alterations but not neurodegeneration in mice. Mol Brain 2013; 6:35. [PMID: 23938054 PMCID: PMC3751304 DOI: 10.1186/1756-6606-6-35] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Accepted: 08/09/2013] [Indexed: 12/13/2022] Open
Abstract
Background In autosomal recessive early-onset Parkinsonism (PARK2), the pathogenetic process from the loss of function of a ubiquitin ligase parkin to the death of dopamine neurons remains unclear. A dominant hypothesis attributes the neurotoxicity to accumulated substrates that are exempt from parkin-mediated degradation. Parkin substrates include two septins; SEPT4/CDCrel-2 which coaggregates with α-synuclein as Lewy bodies in Parkinson’s disease, and its closest homolog SEPT5/CDCrel-1/PNUTL1 whose overload with viral vector can rapidly eliminate dopamine neurons in rats. However, chronic effects of pan-neural overload of septins have never been examined in mammals. To address this, we established a line of transgenic mice that express the largest gene product SEPT454kDa via the prion promoter in the entire brain. Results Histological examination and biochemical quantification of SEPT4-associated proteins including α-synuclein and the dopamine transporter in the nigrostriatal dopamine neurons found no significant difference between Sept4Tg/+ and wild-type littermates. Thus, the hypothetical pathogenicity by the chronic overload of SEPT4 alone, if any, is insufficient to trigger neurodegenerative process in the mouse brain. Intriguingly, however, a systematic battery of behavioral tests revealed unexpected abnormalities in Sept4Tg/+ mice that include consistent attenuation of voluntary activities in distinct behavioral paradigms and altered social behaviors. Conclusions Together, these data indicate that septin dysregulations commonly found in postmortem human brains with Parkinson’s disease, schizophrenia and bipolar disorders may be responsible for a subset of behavioral abnormalities in the patients.
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Affiliation(s)
- Natsumi Ageta-Ishihara
- Department of Molecular Biology, Division of Biological Sciences, Nagoya University Graduate School of Science, Nagoya, Japan
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42
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Lorca T, Castro A. Deciphering the New Role of the Greatwall/PP2A Pathway in Cell Cycle Control. Genes Cancer 2013; 3:712-20. [PMID: 23634258 DOI: 10.1177/1947601912473478] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Mitotic division is induced by protein phosphorylation. For a long time the supported hypothesis was that mitotic entry and exit were the exclusive result of cyclin B-Cdk1 kinase activation and inactivation, whereas the phosphatase activity required to dephosphorylate mitotic substrates was thought to be constant during mitosis. Recent data demonstrate that phosphatase activity must also be tightly regulated to promote correct cell division. Here we describe the new pathway involved in phosphatase regulation and the questions that this discovery raises concerning the classic view of cell cycle regulation.
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Affiliation(s)
- Thierry Lorca
- Universités Montpellier 2 et 1, Centre de Recherche de Biochimie Macromoléculaire, CNRS UMR, Montpellier, France
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43
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Mapping the subcellular distribution of α-synuclein in neurons using genetically encoded probes for correlated light and electron microscopy: implications for Parkinson's disease pathogenesis. J Neurosci 2013; 33:2605-15. [PMID: 23392688 DOI: 10.1523/jneurosci.2898-12.2013] [Citation(s) in RCA: 104] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Modifications to the gene encoding human α-synuclein have been linked to the development of Parkinson's disease. The highly conserved structure of α-synuclein suggests a functional interaction with membranes, and several lines of evidence point to a role in vesicle-related processes within nerve terminals. Using recombinant fusions of human α-synuclein, including new genetic tags developed for correlated light microscopy and electron microscopy (the tetracysteine-biarsenical labeling system or the new fluorescent protein for electron microscopy, MiniSOG), we determined the distribution of α-synuclein when overexpressed in primary neurons at supramolecular and cellular scales in three dimensions (3D). We observed specific association of α-synuclein with a large and otherwise poorly characterized membranous organelle system of the presynaptic terminal, as well as with smaller vesicular structures within these boutons. Furthermore, α-synuclein was localized to multiple elements of the protein degradation pathway, including multivesicular bodies in the axons and lysosomes within neuronal cell bodies. Examination of synapses in brains of transgenic mice overexpressing human α-synuclein revealed alterations of the presynaptic endomembrane systems similar to our findings in cell culture. Three-dimensional electron tomographic analysis of enlarged presynaptic terminals in several brain areas revealed that these terminals were filled with membrane-bounded organelles, including tubulovesicular structures similar to what we observed in vitro. We propose that α-synuclein overexpression is associated with hypertrophy of membrane systems of the presynaptic terminal previously shown to have a role in vesicle recycling. Our data support the conclusion that α-synuclein is involved in processes associated with the sorting, channeling, packaging, and transport of synaptic material destined for degradation.
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44
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The Aggregation of Huntingtin and α-Synuclein. JOURNAL OF BIOPHYSICS 2012; 2012:606172. [PMID: 22899913 PMCID: PMC3412099 DOI: 10.1155/2012/606172] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Revised: 05/15/2012] [Accepted: 05/17/2012] [Indexed: 12/23/2022]
Abstract
Huntington's and Parkinson's diseases are neurodegenerative disorders associated with unusual protein interactions. Although the origin and evolution of these diseases are completely different, characteristic deposits of protein aggregates (huntingtin and α-synuclein resp.), are a common feature in both diseases. After these observations, many studies are performed with both proteins. Some of them try to understand the nature and driving forces of the aggregation process; others try to find a correlation between the genetic and failure in protein function. Finally with the combination of both approaches, it was proposed that possible strategies deal with pathologic aggregation. Unfortunately, if protein aggregation is a cause or a consequence of the neurodegeneration observed in these pathologies, it is still debatable. This paper describes the process of aggregation of two proteins: huntingtin and α synuclein. The characteristics of the aggregation reaction of these proteins have been followed with novel methods both in vivo and in vitro; these studies include both the combination with other proteins and the presence of various chemical compounds. The ultimate goal of this study was to summarize recent findings on protein aggregation and its possible role as a therapeutic target in neurodegenerative diseases and their role in biomaterial science.
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45
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Bellucci A, Zaltieri M, Navarria L, Grigoletto J, Missale C, Spano P. From α-synuclein to synaptic dysfunctions: new insights into the pathophysiology of Parkinson's disease. Brain Res 2012; 1476:183-202. [PMID: 22560500 DOI: 10.1016/j.brainres.2012.04.014] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Revised: 03/30/2012] [Accepted: 04/09/2012] [Indexed: 10/28/2022]
Abstract
Alpha-synuclein is a natively unfolded protein playing a key role in the regulation of several neuronal synaptic functions in physiological and pathological conditions. Many studies, over the past years, have shown that it is actively involved in PD pathophysiology. Alpha-synuclein is integrated in a complex network of neuronal processes through the interaction with cytosolic and synaptic proteins. Hence, it is not the sole α-synuclein pathology but its effects on diverse protein partners and specific cellular pathways in the membrane and/or cytosolic districts such as endoplasmic reticulum/Golgi, axonal and synaptic compartments of dopaminergic neurons, that may cause the onset of neuronal cell dysfunction and degeneration which are among the key pathological features of the PD brain. Here we summarize a series of experimental data supporting that α-synuclein aggregation may induce dysfunction and degeneration of synapses via these multiple mechanisms. Taken together, these data add new insights into the complex mechanisms underlying synaptic derangement in PD and other α-synucleinopathies. This article is part of a Special Issue entitled: Brain Integration.
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Affiliation(s)
- Arianna Bellucci
- Division of Pharmacology, Department of Biomedical Sciences and Biotechnologies and National Institute of Neuroscience, University of Brescia, Brescia, Italy.
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46
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Abstract
New data have recently established that protein phosphorylation during mitosis is the result of a controlled balance between kinase and phosphatase activities and that, as for mitotic kinases, phosphatases are also regulated during cell division. This regulation is at least in part induced by the activation of the Greatwall (Gwl) kinase at mitotic entry. Activated Gwl phosphorylates its substrates cAMP-regulated phospho protein 19 (Arpp19) and α-endosulfine (ENSA), promoting their binding to and the inhibition of PP2A. Interestingly, besides the role of the Gwl-Arpp19/ENSA in the control of mitotic division, new data in yeast support the involvement of this pathway in mRNA stabilization during G(0) program initiation, although in this case the phosphatase PP2A appears not to be implicated. Finally, Gwl activity has been shown to be required for DNA checkpoint recovery. These new findings support the view that Gwl, Arpp19 and ENSA could function as the core of a new signalization pathway that, by targeting different final substrates, could participate in a variety of physiological functions.
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47
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Guo Y, Rosati B, Scarlata S. α-Synuclein increases the cellular level of phospholipase Cβ1. Cell Signal 2012; 24:1109-14. [PMID: 22286107 DOI: 10.1016/j.cellsig.2012.01.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2011] [Revised: 12/30/2011] [Accepted: 01/12/2012] [Indexed: 12/22/2022]
Abstract
α-Synuclein is a conserved protein that is a key component in neurodegenerative plaques [1,2]. α-Synuclein binds strongly to phospholipase Cβ (PLCβ) and promotes Ca2+ release in cells. Here, we show that expression of α-synuclein increases the cellular level of PLCβ1 in two neuronal cell lines: PC12 and SK-N-S-SH. The increase in PLCβ1 is not accompanied by changes in the level of RNA or in ubiquitination. Instead, we find that α-synuclein protects PLCβ1 from trypsin digestion and from degradation by the Ca(+2) activated protease calpain. Calpain removes the C-terminal region of the enzyme which mediates activation by Gα(q). We find that in SK-N-SH cells, α-synuclein reduced degradation of PLCβ1 by calpain during Ca2+ signaling allowing the enzyme to remain sensitive to Gα(q) activation. Taken together, our studies show that α-synuclein protects the integrity of PLCβ1 and its ability to be activated by Gα(q), which may in turn impact Ca2+ signaling.
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Affiliation(s)
- Yuanjian Guo
- Department of Physiology & Biophysics, Stony Book University, Stony Brook, NY 11794-8661, USA
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48
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Bellucci A, Navarria L, Zaltieri M, Missale C, Spano P. α-Synuclein synaptic pathology and its implications in the development of novel therapeutic approaches to cure Parkinson's disease. Brain Res 2011; 1432:95-113. [PMID: 22153624 DOI: 10.1016/j.brainres.2011.11.031] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Revised: 11/11/2011] [Accepted: 11/11/2011] [Indexed: 12/24/2022]
Abstract
Parkinson's disease (PD) is characterized by a progressive loss of dopamine (DA) neurons of the nigrostriatal system and by the presence of Lewy bodies (LB), proteinaceous inclusions mainly composed of filamentous α-synuclein aggregates. Alpha-synuclein is a natively unfolded protein which plays a central role in the control of dopaminergic neuronal functions and which is thought to be critically implicated in PD pathophysiology. Indeed, besides the fact that α-synuclein is the main protein component of LB, genetic studies showed that mutations and multiplications of the α-synuclein gene are responsible for the onset of familial forms of PD. A large body of evidence indicates that α-synuclein pathology at dopaminergic synapses may underlie the onset of neuronal cell dysfunction and degeneration in the PD brain. Thus, since the available therapeutic approaches to cure this disease are still limited, we hypothesized that the analysis of the α-synuclein synaptic proteome/lipidome may represent a tool to identify novel potential therapeutic targets to cure this disorder. We thus performed a critical review of studies describing α-synuclein pathophysiology at synaptic sites in experimental models of PD and in this paper we outline the most relevant findings regarding the specific modulatory effects exerted by α-synuclein in the control of synaptic functions in physiological and pathological conditions. The conclusions of these studies allow to single out novel potential therapeutic targets among the α-synuclein synaptic partners. These targets may be considered for the development of new pharmacological and gene-based strategies to cure PD.
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Affiliation(s)
- Arianna Bellucci
- Division of Pharmacology, Department of Biomedical Sciences and Biotechnology and National Institute of Neuroscience - Italy, School of Medicine, University of Brescia, Brescia, Italy.
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49
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Szego ÉM, Gerhardt E, Kermer P, Schulz JB. A30P α-synuclein impairs dopaminergic fiber regeneration and interacts with L-DOPA replacement in MPTP-treated mice. Neurobiol Dis 2011; 45:591-600. [PMID: 22001606 DOI: 10.1016/j.nbd.2011.09.017] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Revised: 08/29/2011] [Accepted: 09/29/2011] [Indexed: 11/18/2022] Open
Abstract
Parkinson's disease (PD) is the most common neurodegenerative movement disorder and is characterized by the loss of dopaminergic neurons from the substantia nigra pars compacta (SNpc). α-synuclein (αsyn) has been linked to the pathophysiology of PD, because of its mutations causing familial PD and its accumulation in brains of patients with familial and sporadic PD. Dopamine (DA) replacement is the most effective therapy for ameliorating the motor symptoms of PD; however, it remains controversial whether DA-replacement boosts regeneration in the dopaminergic system or accelerates disease progression and enhances neuronal loss. Here, we studied the effect of chronic L-DOPA treatment on dopaminergic neurons in wild-type (WT) and A30P αsyn transgenic mice after MPTP treatment. Acute MPTP intoxication induced degeneration of dopaminergic neurons in both WT and A30P αsyn transgenic mice. A strong regeneration of dopaminergic fibers at 90 days after MPTP was observed in WT mice. In contrast, regeneration was less pronounced in A30P αsyn mice. Chronic L-DOPA treatment after MPTP intoxication did not only reduce the regeneration of nigrostriatal fibers but also led to an increased apoptotic gene-expression profile in the SNpc and to a decline of TH-positive neurons in A30P αsyn. Our findings reveal that the presence of A30P αsyn inhibits the regeneration of nigrostriatal dopaminergic fibers, and that L-DOPA treatment might interact with the pathogenesis in PD.
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Affiliation(s)
- Éva M Szego
- Department of Neurodegeneration and Restorative Research, Georg-August University, DFG Research Center: Molecular Physiology of the Brain (CMPB), Göttingen, 37073, Germany.
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50
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Dikiy I, Eliezer D. Folding and misfolding of alpha-synuclein on membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2011; 1818:1013-8. [PMID: 21945884 DOI: 10.1016/j.bbamem.2011.09.008] [Citation(s) in RCA: 146] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Revised: 09/09/2011] [Accepted: 09/12/2011] [Indexed: 12/23/2022]
Abstract
The protein alpha-synuclein is considered to play a major role in the etiology of Parkinson's disease. Because it is found in a classic amyloid fibril form within the characteristic intra-neuronal Lewy body deposits of the disease, aggregation of the protein is thought to be of critical importance, but the context in which the protein undergoes aggregation within cells remains unknown. The normal function of synucleins is poorly understood, but appears to involve membrane interactions, and in particular reversible binding to synaptic vesicle membranes. Structural studies of different states of alpha-synuclein, in the absence and presence of membranes or membrane mimetics, have led to models of how membrane-bound forms of the protein may contribute both to functional properties of the protein, as well as to membrane-induced self-assembly and aggregation. This article reviews this area, with a focus on a particular model that has emerged in the past few years. This article is part of a Special Issue entitled: Protein Folding in Membranes.
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Affiliation(s)
- Igor Dikiy
- Department of Biochemistry and Program in Structural Biology, Weill Cornell Medical College, New York, NY 10065, USA
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