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Wu X, Wang G, Zhao Z, Qian Z. In silico study on graphene quantum dots modified with various functional groups inhibiting α‑synuclein dimerization. J Colloid Interface Sci 2024; 667:723-730. [PMID: 38641462 DOI: 10.1016/j.jcis.2024.04.111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Revised: 04/06/2024] [Accepted: 04/16/2024] [Indexed: 04/21/2024]
Abstract
HYPOTHESIS Graphene quantum dots (GQDs) with various functional groups are hypothesized to inhibit the α-synuclein (αS) dimerization, a crucial step in Parkinson's disease pathogenesis. The potential of differently functionalized GQDs is systematically explored. EXPERIMENTS All-atom replica-exchange molecular dynamics simulations (accumulating to 75.6 μs) in explicit water were performed to study the dimerization of the αS non-amyloid component region and the influence of GQDs modified with various functional groups. Conformation ensemble, binding behavior, and free energy analysis were conducted. FINDINGS All studied GQDs inhibit β-sheet and backbone hydrogen bond formation in αS dimers, leading to looser oligomeric conformations. Charged GQDs severely impede the growth of extended β-sheets by providing extra contact surface. GQD binding primarily disrupts αS inter-peptide interactions through π-π stacking, CH-π interactions, and for charged GQDs, additionally through salt-bridge and hydrogen bonding interactions. GQD-COO- showed the most optimal inhibitory effect, binding mode, and intensity, which holds promise for the development of nanomedicines targeting amyloid aggregation in neurodegenerative diseases.
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Affiliation(s)
- Xiaoxiao Wu
- Key Laboratory of Exercise and Health Sciences (Ministry of Education), Shanghai Frontiers Science Research Base of Exercise and Metabolic Health, and School of Exercise and Health, Shanghai University of Sport, 399 Changhai Road, Shanghai 200438, China
| | - Gang Wang
- Key Laboratory of Exercise and Health Sciences (Ministry of Education), Shanghai Frontiers Science Research Base of Exercise and Metabolic Health, and School of Exercise and Health, Shanghai University of Sport, 399 Changhai Road, Shanghai 200438, China
| | - Ziqian Zhao
- Key Laboratory of Exercise and Health Sciences (Ministry of Education), Shanghai Frontiers Science Research Base of Exercise and Metabolic Health, and School of Exercise and Health, Shanghai University of Sport, 399 Changhai Road, Shanghai 200438, China
| | - Zhenyu Qian
- Key Laboratory of Exercise and Health Sciences (Ministry of Education), Shanghai Frontiers Science Research Base of Exercise and Metabolic Health, and School of Exercise and Health, Shanghai University of Sport, 399 Changhai Road, Shanghai 200438, China.
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2
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Das D, Mattaparthi VSK. Computational investigation on the conformational dynamics of C-terminal truncated α-synuclein bound to membrane. J Biomol Struct Dyn 2024:1-13. [PMID: 38321955 DOI: 10.1080/07391102.2024.2310788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 01/22/2024] [Indexed: 02/08/2024]
Abstract
Accelerated progression rates in Parkinson's disease (PD) have been linked to C-terminal domain (CTD) truncations of monomeric α-Synuclein (α-Syn), which have been suggested to increase amyloid aggregation in vivo and in vitro. In the brain of PD patients, CTD truncated α-Syn was found to have lower cell viability and tends to increase in the formation of fibrils. The CTD of α-Syn acts as a guard for regulating the normal functioning of α-Syn. The absence of the CTD may allow the N-terminal of α-Syn to interact with the membrane thereby affecting the normal functioning of α-Syn, and all of which will affect the etiology of PD. In this study, the conformational dynamics of CTD truncated α-Syn (1-99 and 1-108) monomers and their effect on the protein-membrane interactions were demonstrated using the all-atom molecular dynamics (MD) simulation method. From the MD analyses, it was noticed that among the two truncated monomers, α-Syn (1-108) was found to be more stable, shows rigidness at the N-terminal region and contains a significant number of intermolecular hydrogen bonds between the non-amyloid β-component (NAC) region and membrane, and lesser number of extended strands. Further, the bending angle in the N-terminal domain was found to be lesser in the α-Syn (1-108) in comparison with the α-Syn (1-99). Our findings suggest that the truncation on the CTD of α-Syn affects its interaction with the membrane and subsequently has an impact on the aggregation.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Dorothy Das
- Molecular Modelling and Simulation Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, Assam, India
| | - Venkata Satish Kumar Mattaparthi
- Molecular Modelling and Simulation Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, Assam, India
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3
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Aubrey LD, Ninkina N, Ulamec SM, Abramycheva NY, Vasili E, Devine OM, Wilkinson M, Mackinnon E, Limorenko G, Walko M, Muwanga S, Amadio L, Peters OM, Illarioshkin SN, Outeiro TF, Ranson NA, Brockwell DJ, Buchman VL, Radford SE. Substitution of Met-38 to Ile in γ-synuclein found in two patients with amyotrophic lateral sclerosis induces aggregation into amyloid. Proc Natl Acad Sci U S A 2024; 121:e2309700120. [PMID: 38170745 PMCID: PMC10786281 DOI: 10.1073/pnas.2309700120] [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: 06/08/2023] [Accepted: 11/17/2023] [Indexed: 01/05/2024] Open
Abstract
α-, β-, and γ-Synuclein are intrinsically disordered proteins implicated in physiological processes in the nervous system of vertebrates. α-synuclein (αSyn) is the amyloidogenic protein associated with Parkinson's disease and certain other neurodegenerative disorders. Intensive research has focused on the mechanisms that cause αSyn to form amyloid structures, identifying its NAC region as being necessary and sufficient for amyloid assembly. Recent work has shown that a 7-residue sequence (P1) is necessary for αSyn amyloid formation. Although γ-synuclein (γSyn) is 55% identical in sequence to αSyn and its pathological deposits are also observed in association with neurodegenerative conditions, γSyn is resilient to amyloid formation in vitro. Here, we report a rare single nucleotide polymorphism (SNP) in the SNCG gene encoding γSyn, found in two patients with amyotrophic lateral sclerosis (ALS). The SNP results in the substitution of Met38 with Ile in the P1 region of the protein. These individuals also had a second, common and nonpathological, SNP in SNCG resulting in the substitution of Glu110 with Val. In vitro studies demonstrate that the Ile38 variant accelerates amyloid fibril assembly. Contrastingly, Val110 retards fibril assembly and mitigates the effect of Ile38. Substitution of residue 38 with Leu had little effect, while Val retards, and Ala increases the rate of amyloid formation. Ile38 γSyn also results in the formation of γSyn-containing inclusions in cells. The results show how a single point substitution can enhance amyloid formation of γSyn and highlight the P1 region in driving amyloid formation in another synuclein family member.
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Affiliation(s)
- Liam D. Aubrey
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Science, University of Leeds, LeedsLS2 9JT, United Kingdom
| | - Natalia Ninkina
- School of Biosciences, Cardiff University, CardiffCF10 3AX, United Kingdom
- Department of Pharmacology and Clinical Pharmacology, Belgorod State National Research University, Belgorod308015, Russian Federation
| | - Sabine M. Ulamec
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Science, University of Leeds, LeedsLS2 9JT, United Kingdom
| | - Natalia Y. Abramycheva
- Laboratory of Neurobiology and Tissue Engineering, Brain Science Institute, Research Center of Neurology, Moscow125367, Russia
| | - Eftychia Vasili
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Institute of Bioengineering, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, LausanneCH-1015, Switzerland
| | - Oliver M. Devine
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Science, University of Leeds, LeedsLS2 9JT, United Kingdom
| | - Martin Wilkinson
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Science, University of Leeds, LeedsLS2 9JT, United Kingdom
| | - Eilish Mackinnon
- School of Biosciences, Cardiff University, CardiffCF10 3AX, United Kingdom
| | - Galina Limorenko
- School of Biosciences, Cardiff University, CardiffCF10 3AX, United Kingdom
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Institute of Bioengineering, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, LausanneCH-1015, Switzerland
| | - Martin Walko
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Science, University of Leeds, LeedsLS2 9JT, United Kingdom
- Astbury Centre for Structural Molecular Biology, School of Chemistry, University of Leeds, LeedsLS2 9JT, United Kingdom
| | - Sarah Muwanga
- School of Biosciences, Cardiff University, CardiffCF10 3AX, United Kingdom
| | - Leonardo Amadio
- School of Biosciences, Cardiff University, CardiffCF10 3AX, United Kingdom
| | - Owen M. Peters
- School of Biosciences, Cardiff University, CardiffCF10 3AX, United Kingdom
| | - Sergey N. Illarioshkin
- Laboratory of Neurobiology and Tissue Engineering, Brain Science Institute, Research Center of Neurology, Moscow125367, Russia
| | - Tiago F. Outeiro
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, Göttingen37075, Germany
- Max Planck Institute for Multidisciplinary Sciences, Goettingen37075, Germany
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon TyneNE2 4HH, United Kingdom
- Scientific employee with a honorary contract at Deutsches Zentrum für Neurodegenerative Erkrankungen, Göttingen37075, Germany
| | - Neil A. Ranson
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Science, University of Leeds, LeedsLS2 9JT, United Kingdom
| | - David J. Brockwell
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Science, University of Leeds, LeedsLS2 9JT, United Kingdom
| | - Vladimir L. Buchman
- School of Biosciences, Cardiff University, CardiffCF10 3AX, United Kingdom
- Department of Pharmacology and Clinical Pharmacology, Belgorod State National Research University, Belgorod308015, Russian Federation
| | - Sheena E. Radford
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Science, University of Leeds, LeedsLS2 9JT, United Kingdom
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Chopra A, Outeiro TF. Aggregation and beyond: alpha-synuclein-based biomarkers in synucleinopathies. Brain 2024; 147:81-90. [PMID: 37526295 DOI: 10.1093/brain/awad260] [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: 04/13/2023] [Revised: 07/12/2023] [Accepted: 07/15/2023] [Indexed: 08/02/2023] Open
Abstract
Parkinson's disease is clinically known for the loss of dopaminergic neurons in the substantia nigra pars compacta and accumulation of intraneuronal cytoplasmic inclusions rich in alpha-synuclein called 'Lewy bodies' and 'Lewy neurites'. Together with dementia with Lewy bodies and multiple system atrophy, Parkinson's disease is part of a group of disorders called synucleinopathies. Currently, diagnosis of synucleinopathies is based on the clinical assessment which often takes place in advanced disease stages. While the causal role of alpha-synuclein aggregates in these disorders is still debatable, measuring the levels, types or seeding properties of different alpha-synuclein species hold great promise as biomarkers. Recent studies indicate significant differences in peptide, protein and RNA levels in blood samples from patients with Parkinson's disease. Seed amplification assays using CSF, blood, skin biopsy, olfactory swab samples show great promise for detecting synucleinopathies and even for discriminating between different synucleinopathies. Interestingly, small extracellular vesicles, such as exosomes, display differences in their cargoes in Parkinson's disease patients versus controls. In this update, we focus on alpha-synuclein aggregation and possible sources of disease-related species released in extracellular vesicles, which promise to revolutionize the diagnosis and the monitoring of disease progression.
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Affiliation(s)
- Avika Chopra
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, 37073 Göttingen, Germany
| | - Tiago Fleming Outeiro
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, 37073 Göttingen, Germany
- Max Planck Institute for Multidisciplinary Sciences, 37075 Göttingen, Germany
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne NE2 4HH, UK
- Scientific Employee with an Honorary Contract at Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE), 37075 Göttingen, Germany
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5
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Jurcau A, Andronie-Cioara FL, Nistor-Cseppento DC, Pascalau N, Rus M, Vasca E, Jurcau MC. The Involvement of Neuroinflammation in the Onset and Progression of Parkinson's Disease. Int J Mol Sci 2023; 24:14582. [PMID: 37834030 PMCID: PMC10573049 DOI: 10.3390/ijms241914582] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 09/22/2023] [Accepted: 09/24/2023] [Indexed: 10/15/2023] Open
Abstract
Parkinson's disease is a neurodegenerative disease exhibiting the fastest growth in incidence in recent years. As with most neurodegenerative diseases, the pathophysiology is incompletely elucidated, but compelling evidence implicates inflammation, both in the central nervous system and in the periphery, in the initiation and progression of the disease, although it is not yet clear what triggers this inflammatory response and where it begins. Gut dysbiosis seems to be a likely candidate for the initiation of the systemic inflammation. The therapies in current use provide only symptomatic relief, but do not interfere with the disease progression. Nonetheless, animal models have shown promising results with therapies that target various vicious neuroinflammatory cascades. Translating these therapeutic strategies into clinical trials is still in its infancy, and a series of issues, such as the exact timing, identifying biomarkers able to identify Parkinson's disease in early and pre-symptomatic stages, or the proper indications of genetic testing in the population at large, will need to be settled in future guidelines.
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Affiliation(s)
- Anamaria Jurcau
- Department of Psycho-Neuroscience and Rehabilitation, Faculty of Medicine and Pharmacy, University of Oradea, 410073 Oradea, Romania; (A.J.); (D.C.N.-C.)
| | - Felicia Liana Andronie-Cioara
- Department of Psycho-Neuroscience and Rehabilitation, Faculty of Medicine and Pharmacy, University of Oradea, 410073 Oradea, Romania; (A.J.); (D.C.N.-C.)
| | - Delia Carmen Nistor-Cseppento
- Department of Psycho-Neuroscience and Rehabilitation, Faculty of Medicine and Pharmacy, University of Oradea, 410073 Oradea, Romania; (A.J.); (D.C.N.-C.)
| | - Nicoleta Pascalau
- Department of Psycho-Neuroscience and Rehabilitation, Faculty of Medicine and Pharmacy, University of Oradea, 410073 Oradea, Romania; (A.J.); (D.C.N.-C.)
| | - Marius Rus
- Department of Medical Disciplines, Faculty of Medicine and Pharmacy, University of Oradea, 410087 Oradea, Romania
| | - Elisabeta Vasca
- Department of Oral Rehabilitation, Faculty of Medicine “Vasile Goldis” Arad, 310025 Arad, Romania
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6
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Aminabad ED, Hasanzadeh M, Ahmadalipour A, Mahmoudi T, Feizi MAH, Safaralizadeh R, Mobed A. Sensitive electrochemical recognition of α-synuclein protein in human plasma samples using bioconjugated gold nanoparticles: An innovative immuno-platform to assist in the early stage identification of Parkinson's disease by biosensor technology. J Mol Recognit 2023; 36:e2952. [PMID: 34985150 DOI: 10.1002/jmr.2952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 12/21/2021] [Accepted: 01/02/2022] [Indexed: 11/07/2022]
Abstract
This research work explains the development of an electrochemical immunosensor for the selective recognition of SNCA in human biofluids. An innovative protocol was proposed for the green synthesis of gold nanoparticle-supported dimethylglyoxime (AuNPs@DMGO) using one-step electrogeneration method. Also, the application of AuNPs@DMGO for the sensitive quantification of α-Synuclein (SNCA) protein and its biomedical analysis. So, an innovative sandwich immunosensor was designed for the sensitive identification of SNCA antigen in an aqueous solution. The gold nanoparticles (AuNPs) were decorated on the surface of the glassy carbon electrode by chronoamperometry technique to provide appropriate immobilization surface with a large number of active sites for immobilization of specific biotinylated antibody (Ab1) and against SNCA protein. Then, the sandwich-type immuno-platform was completed by the attachment of secondary antibody (HRP conjugated Ab [Ab2]) to the primary complexes on the surface of the electrode. For the first time, α-Synuclein protein was measured with an acceptable linear range of 4-64 ng/mL and a lower limit of quantification of 4 ng/mL. Benefiting from the simplicity and high sensitivity, the proposed method shows a potential of employment in clinical applications and high-throughput screening of Parkinson's disease using POC.
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Affiliation(s)
- Esmaeil Darvish Aminabad
- Department of Biology, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran.,Pharmaceutical Analysis Recent Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Hasanzadeh
- Pharmaceutical Analysis Recent Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Nutrition Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Ali Ahmadalipour
- Research Center of Psychiatry and Behavioral Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Tohid Mahmoudi
- Pharmaceutical Analysis Reserch center, Tabriz University of Medical Science, Tabriz, Iran
| | | | - Reza Safaralizadeh
- Department of Biology, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran
| | - Ahmad Mobed
- Pharmaceutical Analysis Reserch center, Tabriz University of Medical Science, Tabriz, Iran.,Aging Research Institute, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
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7
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Interneuronal In Vivo Transfer of Synaptic Proteins. Cells 2023; 12:cells12040569. [PMID: 36831238 PMCID: PMC9954582 DOI: 10.3390/cells12040569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 02/06/2023] [Accepted: 02/08/2023] [Indexed: 02/12/2023] Open
Abstract
Neuron-to-neuron transfer of pathogenic α-synuclein species is a mechanism of likely relevance to Parkinson's disease development. Experimentally, interneuronal α-synuclein spreading from the low brainstem toward higher brain regions can be reproduced by the administration of AAV vectors encoding for α-synuclein into the mouse vagus nerve. The aim of this study was to determine whether α-synuclein's spreading ability is shared by other proteins. Given α-synuclein synaptic localization, experiments involved intravagal injections of AAVs encoding for other synaptic proteins, β-synuclein, VAMP2, or SNAP25. Administration of AAV-VAMP2 or AAV-SNAP25 caused robust transduction of either of the proteins in the dorsal medulla oblongata but was not followed by interneuronal VAMP2 or SNAP25 transfer and caudo-rostral spreading. In contrast, AAV-mediated β-synuclein overexpression triggered its spreading to more frontal brain regions. The aggregate formation was investigated as a potential mechanism involved in protein spreading, and consistent with this hypothesis, results showed that overexpression of β-synuclein, but not VAMP2 or SNAP25, in the dorsal medulla oblongata was associated with pronounced protein aggregation. Data indicate that interneuronal protein transfer is not a mere consequence of increased expression or synaptic localization. It is rather promoted by structural/functional characteristics of synuclein proteins that likely include their tendency to form aggregate species.
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8
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Myers AJ, Brahimi A, Jenkins IJ, Koob AO. The Synucleins and the Astrocyte. BIOLOGY 2023; 12:biology12020155. [PMID: 36829434 PMCID: PMC9952504 DOI: 10.3390/biology12020155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 01/13/2023] [Accepted: 01/16/2023] [Indexed: 01/21/2023]
Abstract
Synucleins consist of three proteins exclusively expressed in vertebrates. α-Synuclein (αS) has been identified as the main proteinaceous aggregate in Lewy bodies, a pathological hallmark of many neurodegenerative diseases. Less is understood about β-synuclein (βS) and γ-synuclein (γS), although it is known βS can interact with αS in vivo to inhibit aggregation. Likewise, both γS and βS can inhibit αS's propensity to aggregate in vitro. In the central nervous system, βS and αS, and to a lesser extent γS, are highly expressed in the neural presynaptic terminal, although they are not strictly located there, and emerging data have shown a more complex expression profile. Synapse loss and astrocyte atrophy are early aspects of degenerative diseases of the brain and correlate with disease progression. Synucleins appear to be involved in synaptic transmission, and astrocytes coordinate and organize synaptic function, with excess αS degraded by astrocytes and microglia adjacent to the synapse. βS and γS have also been observed in the astrocyte and may provide beneficial roles. The astrocytic responsibility for degradation of αS as well as emerging evidence on possible astrocytic functions of βS and γS, warrant closer inspection on astrocyte-synuclein interactions at the synapse.
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Affiliation(s)
- Abigail J. Myers
- Neuroscience Program, Health Science Research Facility, University of Vermont, 149 Beaumont Ave., Burlington, VT 05405, USA
| | - Ayat Brahimi
- Biology Department, University of Hartford, 200 Bloomfield Ave., West Hartford, CT 06117, USA
| | - Imani J. Jenkins
- Biology Department, University of Hartford, 200 Bloomfield Ave., West Hartford, CT 06117, USA
| | - Andrew O. Koob
- Biology Department, University of Hartford, 200 Bloomfield Ave., West Hartford, CT 06117, USA
- Correspondence: ; Tel.: +1-860-768-5780
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Estaun-Panzano J, Arotcarena ML, Bezard E. Monitoring α-synuclein aggregation. Neurobiol Dis 2023; 176:105966. [PMID: 36527982 PMCID: PMC9875312 DOI: 10.1016/j.nbd.2022.105966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 12/12/2022] [Accepted: 12/14/2022] [Indexed: 12/23/2022] Open
Abstract
Synucleinopathies, including Parkinson's disease (PD), dementia with Lewy Bodies (DLB), and multiple system atrophy (MSA), are characterized by the misfolding and subsequent aggregation of alpha-synuclein (α-syn) that accumulates in cytoplasmic inclusions bodies in the cells of affected brain regions. Since the seminal report of likely-aggregated α-syn presence within the Lewy bodies by Spillantini et al. in 1997, the keyword "synuclein aggregation" has appeared in over 6000 papers (Source: PubMed October 2022). Studying, observing, describing, and quantifying α-syn aggregation is therefore of paramount importance, whether it happens in tubo, in vitro, in post-mortem samples, or in vivo. The past few years have witnessed tremendous progress in understanding aggregation mechanisms and identifying various polymorphs. In this context of growing complexity, it is of utmost importance to understand what tools we possess, what exact information they provide, and in what context they may be applied. Nonetheless, it is also crucial to rationalize the relevance of the information and the limitations of these methods for gauging the final result. In this review, we present the main techniques that have shaped the current views about α-syn structure and dynamics, with particular emphasis on the recent breakthroughs that may change our understanding of synucleinopathies.
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Affiliation(s)
| | | | - Erwan Bezard
- Univ. Bordeaux, CNRS, IMN, UMR 5293, F-33000 Bordeaux, France; Motac Neuroscience Ltd, Manchester, United Kingdom.
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10
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Synucleins: New Data on Misfolding, Aggregation and Role in Diseases. Biomedicines 2022; 10:biomedicines10123241. [PMID: 36551997 PMCID: PMC9775291 DOI: 10.3390/biomedicines10123241] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 12/05/2022] [Accepted: 12/07/2022] [Indexed: 12/15/2022] Open
Abstract
The synucleins are a family of natively unfolded (or intrinsically unstructured) proteins consisting of α-, β-, and γ-synuclein involved in neurodegenerative diseases and cancer. The current number of publications on synucleins has exceeded 16.000. They remain the subject of constant interest for over 35 years. Two reasons explain this unchanging attention: synuclein's association with several severe human diseases and the lack of understanding of the functional roles under normal physiological conditions. We analyzed recent publications to look at the main trends and developments in synuclein research and discuss possible future directions. Traditional areas of peak research interest which still remain high among last year's publications are comparative studies of structural features as well as functional research on of three members of the synuclein family. Another popular research topic in the area is a mechanism of α-synuclein accumulation, aggregation, and fibrillation. Exciting fast-growing area of recent research is α-synuclein and epigenetics. We do not present here a broad and comprehensive review of all directions of studies but summarize only the most significant recent findings relevant to these topics and outline potential future directions.
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11
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Single residue modulators of amyloid formation in the N-terminal P1-region of α-synuclein. Nat Commun 2022; 13:4986. [PMID: 36008493 PMCID: PMC9411612 DOI: 10.1038/s41467-022-32687-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 08/10/2022] [Indexed: 11/09/2022] Open
Abstract
Alpha-synuclein (αSyn) is a protein involved in neurodegenerative disorders including Parkinson’s disease. Amyloid formation of αSyn can be modulated by the ‘P1 region’ (residues 36-42). Here, mutational studies of P1 reveal that Y39A and S42A extend the lag-phase of αSyn amyloid formation in vitro and rescue amyloid-associated cytotoxicity in C. elegans. Additionally, L38I αSyn forms amyloid fibrils more rapidly than WT, L38A has no effect, but L38M does not form amyloid fibrils in vitro and protects from proteotoxicity. Swapping the sequence of the two residues that differ in the P1 region of the paralogue γSyn to those of αSyn did not enhance fibril formation for γSyn. Peptide binding experiments using NMR showed that P1 synergises with residues in the NAC and C-terminal regions to initiate aggregation. The remarkable specificity of the interactions that control αSyn amyloid formation, identifies this region as a potential target for therapeutics, despite their weak and transient nature. The authors of this work characterize the effect of amino acid substitution on α-synuclein (α-Syn) aggregation. Residues 38 and 42 (in addition to 39) within the P1 region of α-Syn affect amyloid formation. The effect of substitution at position 38 is dependent on the amino-acid introduced, suggesting that specific interactions control α -Syn aggregation.
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12
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Galamba N. Aggregation of a Parkinson's Disease-Related Peptide: When Does Urea Weaken Hydrophobic Interactions? ACS Chem Neurosci 2022; 13:1769-1781. [PMID: 35616516 PMCID: PMC9775218 DOI: 10.1021/acschemneuro.2c00169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
While the exact cause of neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease is not completely understood, compelling evidence implicates the aggregation of specific proteins and peptides. Co-solvents can provide molecular insight into protein aggregation mechanisms and the chemical nature of potential aggregation inhibitors. Here, we study, through molecular simulations, the hydration and binding free energies of an amphiphilic peptide from the nonamyloid-β component (NAC), a key aggregation-prone domain of α-synuclein, in water and an 8 M aqueous urea solution. Isoleucine, glycine, and serine peptides of the same length are also studied to unravel the role of urea in the hydration and aggregation of hydrophobic and hydrophilic domains. A strong impact of urea in hindering the aggregation of the NAC subdomain is observed. A slightly weaker aggregation inhibition is observed for the Gly and Ser peptides, whereas a much lower aggregation inhibitory activity is found for the Ile peptide, seemingly contrasting with urea's protein unfolding mechanism. This behavior is shown to derive from a lower profusion of urea next to the hydrophobic side chains and the backbone of the Ile's peptide in the dimeric form. As a consequence, β-sheets, formed upon aggregation, remain nearly intact. Hydrophilic neighbor groups in the amphiphilic NAC subdomain, however, are shown to anchor enough urea to weaken hydrophobic interactions and disrupt β-sheet structures. Our results indicate that urea's activity is potentiated in amphiphilic domains and that potential drugs could disrupt hydrophobic β-sheet-rich regions while not binding primarily to hydrophobic amino acids.
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Han M, Li Y, Lu S, Yuan B, Cheng S, Cao C. Amyloid Protein-Biofunctionalized Polydopamine Nanoparticles Demonstrate Minimal Plasma Protein Fouling and Efficient Photothermal Therapy. ACS APPLIED MATERIALS & INTERFACES 2022; 14:13743-13757. [PMID: 35263991 DOI: 10.1021/acsami.2c00716] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Polydopamine (PDA) shows great application potential in photothermal therapy (PTT) of tumors due to its excellent photothermal performance. However, PDA rich in a large number of catechin structures, with strong adhesion, can readily attach to plasma proteins in blood to form protein corona, which greatly hinders the transfer efficiency to tumors and reduces the bioavailability. In this paper, a simple, rapid phase-transitioned albumin biomimetic nanocorona (TBSA) is used for the surface camouflage of PDA nanoparticles for minimal plasma protein fouling and efficient PTT. TBSA coating is formed by the BSA-derived amyloid through the hydrophobic aggregation near the isoelectric point and the rupture of disulfide bonds by tris(2-carboxyethyl) phosphine. The stable PDA@TBSA complexes are formed by camouflaging TBSA onto the surface of PDA through hydrophobic, electrostatic, and covalent binding between TBSA and PDA, which showed excellent anti-plasma protein adsorption properties profited from the surface charge of PDA@TBSA approaching equilibrium and the surface passivation of BSA. The plasma protein thickness of the PDA@TBSA surface is 6 times lower than that of PDA at adsorption saturation. In vitro and in vivo experiments have revealed that PDA@TBSA has an excellent photothermal antitumor effect compared to PDA. Both PDA and PDA@TBSA treatment plus 808 nm laser irradiation result in more than 70% inhibition on tumor cell proliferation. In addition, PDA@TBSA does not cause a significant inflammatory response and tissue damage. Taken together, the TBSA coating endows PDA with low-fouling functions in blood and improves the residence time of PDA in blood and enrichment in the tumor tissue. This work offers a novel and efficient strategy for the design of functional nanosystems exploiting the speciality of the biomolecular corona formation around nanomaterials.
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Affiliation(s)
- Miaomiao Han
- Department of Food Quality and Safety/National R&D Center for Chinese Herbal Medicine Processing, College of Engineering, China Pharmaceutical University, Nanjing 211198, China
| | - Yan Li
- Department of Food Quality and Safety/National R&D Center for Chinese Herbal Medicine Processing, College of Engineering, China Pharmaceutical University, Nanjing 211198, China
| | - Shun Lu
- Department of Food Quality and Safety/National R&D Center for Chinese Herbal Medicine Processing, College of Engineering, China Pharmaceutical University, Nanjing 211198, China
| | - Biao Yuan
- Department of Food Quality and Safety/National R&D Center for Chinese Herbal Medicine Processing, College of Engineering, China Pharmaceutical University, Nanjing 211198, China
| | - Shujie Cheng
- Department of Food Quality and Safety/National R&D Center for Chinese Herbal Medicine Processing, College of Engineering, China Pharmaceutical University, Nanjing 211198, China
| | - Chongjiang Cao
- Department of Food Quality and Safety/National R&D Center for Chinese Herbal Medicine Processing, College of Engineering, China Pharmaceutical University, Nanjing 211198, China
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Singh A, Maharana SK, Shukla R, Kesharwani P. Nanotherapeutics approaches for targeting alpha synuclien protein in the management of Parkinson disease. Process Biochem 2021. [DOI: 10.1016/j.procbio.2021.08.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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15
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Guschina IA, Ninkina N, Roman A, Pokrovskiy MV, Buchman VL. Triple-Knockout, Synuclein-Free Mice Display Compromised Lipid Pattern. Molecules 2021; 26:molecules26113078. [PMID: 34064018 PMCID: PMC8196748 DOI: 10.3390/molecules26113078] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 05/05/2021] [Accepted: 05/11/2021] [Indexed: 11/29/2022] Open
Abstract
Recent studies have implicated synucleins in several reactions during the biosynthesis of lipids and fatty acids in addition to their recognised role in membrane lipid binding and synaptic functions. These are among aspects of decreased synuclein functions that are still poorly acknowledged especially in regard to pathogenesis in Parkinson’s disease. Here, we aimed to add to existing knowledge of synuclein deficiency (i.e., the lack of all three family members), with respect to changes in fatty acids and lipids in plasma, liver, and two brain regions in triple synuclein-knockout (TKO) mice. We describe changes of long-chain polyunsaturated fatty acids (LCPUFA) and palmitic acid in liver and plasma, reduced triacylglycerol (TAG) accumulation in liver and non-esterified fatty acids in plasma of synuclein free mice. In midbrain, we observed counterbalanced changes in the relative concentrations of phosphatidylcholine (PC) and cerebrosides (CER). We also recorded a notable reduction in ethanolamine plasmalogens in the midbrain of synuclein free mice, which is an important finding since the abnormal ether lipid metabolism usually associated with neurological disorders. In summary, our data demonstrates that synuclein deficiency results in alterations of the PUFA synthesis, storage lipid accumulation in the liver, and the reduction of plasmalogens and CER, those polar lipids which are principal compounds of lipid rafts in many tissues. An ablation of all three synuclein family members causes more profound changes in lipid metabolism than changes previously shown to be associated with γ-synuclein deficiency alone. Possible mechanisms by which synuclein deficiency may govern the reported modifications of lipid metabolism in TKO mice are proposed and discussed.
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Affiliation(s)
- Irina A. Guschina
- School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK; (N.N.); (A.R.); (V.L.B.)
- Correspondence:
| | - Natalia Ninkina
- School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK; (N.N.); (A.R.); (V.L.B.)
- Institute of Physiologically Active Compounds Russian Academy of Sciences (IPAC RAS), 1 Severniy Proezd, Chernogolovka 142432, Moscow Region, Russia
| | - Andrei Roman
- School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK; (N.N.); (A.R.); (V.L.B.)
- Institute of Physiologically Active Compounds Russian Academy of Sciences (IPAC RAS), 1 Severniy Proezd, Chernogolovka 142432, Moscow Region, Russia
| | - Mikhail V. Pokrovskiy
- Research Institute of Living Systems Pharmacology, Belgorod State National Research University, 85 Pobedy Street, Belgorod 308015, Belgorod Oblast, Russia;
| | - Vladimir L. Buchman
- School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK; (N.N.); (A.R.); (V.L.B.)
- Institute of Physiologically Active Compounds Russian Academy of Sciences (IPAC RAS), 1 Severniy Proezd, Chernogolovka 142432, Moscow Region, Russia
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16
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Modulation of α-synuclein fibrillation by plant metabolites, daidzein, fisetin and scopoletin under physiological conditions. Int J Biol Macromol 2021; 182:1278-1291. [PMID: 33991558 DOI: 10.1016/j.ijbiomac.2021.05.071] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 04/01/2021] [Accepted: 05/10/2021] [Indexed: 12/11/2022]
Abstract
The aggregation of α-synuclein is linked to neurological disorders, and of these, Parkinson's disease (PD) is among the most widely studied. In this background, we have investigated here the effects of three α, β-unsaturated carbonyl based plant metabolites, daidzein, fisetin and scopoletin on α-Syn aggregation. The ThT and light scattering kinetics studies establish that these compounds have ability to inhibit α-Syn fibrillation to different extents; this is confirmed by TEM studies. It is pertinent to note here that daidzein and scopoletin have been predicted to be able to cross the blood brain barrier. ANS binding assays demonstrate that the compounds interfere in the hydrophobic interactions. The tyrosine quenching, molecular docking and MD simulation studies showed that the compounds bind with α-Syn and provide structural rigidity which delays onset of structural transitions, which is confirmed by CD spectroscopy. The results obtained here throw light on the mechanisms underlying inhibition of α-Syn fibrillation by these compounds. Thus, the current work has significant therapeutic implications for identifying plant based potent therapeutic molecules for PD and other synucleinopathies, an area which needs extensive exploration.
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17
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Yamauchi M, Okumura H. Dimerization of α-Synuclein Fragments Studied by Isothermal-Isobaric Replica-Permutation Molecular Dynamics Simulation. J Chem Inf Model 2021; 61:1307-1321. [PMID: 33625841 DOI: 10.1021/acs.jcim.0c01056] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Aggregates and fibrils of intrinsically disordered α-synuclein are associated with Parkinson's disease. Within a non-amyloid β component (NAC) spanning from the 61st to the 95th residue of α-synuclein, an 11-residue segment called NACore (68GAVVTGVTAVA78) is an essential region for both fibril formation and cytotoxicity. Although NACore peptides alone are known to form aggregates and amyloid fibrils, the mechanisms of aggregation and fibrillation remain unknown. This study investigated the dimerization process of NACore peptides as the initial stage of the aggregation and fibrillation processes. We performed an isothermal-isobaric replica-permutation molecular dynamics simulation, which is one of the efficient sampling methods, for the two NACore peptides in explicit water over 96 μs. The simulation succeeded in sampling a variety of dimer structures. An analysis of secondary structure revealed that most of the NACore dimers form intermolecular β-bridges. In particular, more antiparallel β-bridges were observed than parallel β-bridges. We also found that intramolecular secondary structures such as α-helix and antiparallel β-bridge are stabilized in the pre-dimer state. However, we identified that the intermolecular β-bridges tend to form directly between residues with no specific structure rather than via the intramolecular β-bridges. This is because the NACore peptides still have a low propensity to form the intramolecular secondary structures even though they are stabilized in the pre-dimer state.
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Affiliation(s)
- Masataka Yamauchi
- Department of Structural Molecular Science, The Graduate University for Advanced Studies(SOKENDAI), Okazaki, Aichi 444-8787, Japan.,Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan.,Institute for Molecular Science (IMS), National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan
| | - Hisashi Okumura
- Department of Structural Molecular Science, The Graduate University for Advanced Studies(SOKENDAI), Okazaki, Aichi 444-8787, Japan.,Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan.,Institute for Molecular Science (IMS), National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan
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18
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Kamboj S, Harms C, Kumar L, Creamer D, West C, Klein-Seetharaman J, Sarkar SK. A method of purifying alpha-synuclein in E. coli without chromatography. Heliyon 2021; 7:e05874. [PMID: 33490665 PMCID: PMC7810624 DOI: 10.1016/j.heliyon.2020.e05874] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Revised: 02/18/2020] [Accepted: 12/24/2020] [Indexed: 11/23/2022] Open
Abstract
Research has implicated alpha-synuclein (aSyn) in pathological protein aggregation observed in almost all patients with Parkinson's disease and more than 50% of patients with Alzheimer's disease. An easy and inexpensive method of purifying aSyn and developing an in vitro model system of Lewy body formation would enhance basic biomedical research. We report aSyn purification technique that leverages the amyloidogenic property of aSyn suitable for purifying monomeric aSyn without chromatography and denaturing agents. We expressed full-length and untagged aSyn in Rosetta(DE3) pLysS and purified ~60 μg of aSyn from 500 mL culture within 24 h. After IPTG-induced expression of aSyn in E. coli, we disrupted the cells with a sonicator. We centrifuged the cell lysate in a 15 mL tube, which leads to aSyn-induced aggregation of native E. coli proteins. After removing aggregates, centrifugation in a 30 kDa cut-off filter followed by a 10 kDa cut-off filter led to purified water-soluble aSyn. The identity of aSyn was confirmed by Western blot using anti-aSyn antibody and Edman sequencing. Its mass was determined to be 14.6 kDa using a MALDI TOF-MS mass spectrometer. The majority of aSyn led to water-suspended (as opposed to precipitated) aggregation of E. coli proteins with visible fibrous structures. The broad-spectrum binding and amyloidogenic property of aSyn is thus not only useful for inexpensive aSyn production for diverse applications, but it also expands studying its possible roles in human physiology. The aggregate of E. coli proteins induced by aSyn during the purification process may serve as a Lewy body model.
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Affiliation(s)
- Sumaer Kamboj
- Department of Physics, Colorado School of Mines, Golden, CO 80401, USA
| | - Chase Harms
- Department of Physics, Colorado School of Mines, Golden, CO 80401, USA
| | - Lokender Kumar
- Department of Physics, Colorado School of Mines, Golden, CO 80401, USA
| | - Daniel Creamer
- Department of Physics, Colorado School of Mines, Golden, CO 80401, USA
| | - Colista West
- Department of Chemistry, Colorado School of Mines, Golden, CO 80401, USA
| | | | - Susanta K. Sarkar
- Department of Physics, Colorado School of Mines, Golden, CO 80401, USA
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19
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Cahill CM, Aleyadeh R, Gao J, Wang C, Rogers JT. Alpha-Synuclein in Alcohol Use Disorder, Connections with Parkinson's Disease and Potential Therapeutic Role of 5' Untranslated Region-Directed Small Molecules. Biomolecules 2020; 10:E1465. [PMID: 33096655 PMCID: PMC7589448 DOI: 10.3390/biom10101465] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 09/28/2020] [Accepted: 10/09/2020] [Indexed: 12/23/2022] Open
Abstract
Alpha-synuclein (α-Syn) is a 140-amino acid (aa) protein encoded by the Synuclein alpha SNCA gene. It is the synaptic protein associated with Parkinson's disease (PD) and is the most highly expressed protein in the Lewy bodies associated with PD and other alpha synucleopathies, including Lewy body dementia (LBD) and multiple system atrophy (MSA). Iron deposits are present in the core of Lewy bodies, and there are reports suggesting that divalent metal ions including Cu2+ and Fe2+ enhance the aggregation of α-Syn. Differential expression of α-Syn is associated with alcohol use disorder (AUD), and specific genetic variants contribute to the risk for alcoholism, including alcohol craving. Spliced variants of α-Syn, leading to the expression of several shorter forms which are more prone to aggregation, are associated with both PD and AUD, and common transcript variants may be able to predict at-risk populations for some movement disorders or subtypes of PD, including secondary Parkinsonism. Both PD and AUD are associated with liver and brain iron dyshomeostasis. Research over the past decade has shown that α-Syn has iron import functions with an ability to oxidize the Fe3+ form of iron to Fe2+ to facilitate its entry into cells. Our prior research has identified an iron-responsive element (IRE) in the 5' untranslated region (5'UTR) of α-Syn mRNA, and we have used the α-Syn 5'UTR to screen for small molecules that modulate its expression in the H4 neuronal cell line. These screens have led us to identify several interesting small molecules capable of both decreasing and increasing α-Syn expression and that may have the potential, together with the recently described mesenchymal stem cell therapies, to normalize α-Syn expression in different regions of the alcoholic and PD brain.
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Affiliation(s)
- Catherine M. Cahill
- Neurochemistry Laboratory, Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA;
| | | | - Jin Gao
- Department of Clinical Psychology, Qilu Hospital of Shandong University, Qingdao 266011, China;
| | - Changning Wang
- Athinoula A. Martinos Center for Biomedical Imaging Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA;
| | - Jack T. Rogers
- Neurochemistry Laboratory, Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA;
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20
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Skaanning LK, Santoro A, Skamris T, Martinsen JH, D’Ursi AM, Bucciarelli S, Vestergaard B, Bugge K, Langkilde AE, Kragelund BB. The Non-Fibrillating N-Terminal of α-Synuclein Binds and Co-Fibrillates with Heparin. Biomolecules 2020; 10:E1192. [PMID: 32824376 PMCID: PMC7464290 DOI: 10.3390/biom10081192] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 08/12/2020] [Accepted: 08/14/2020] [Indexed: 01/16/2023] Open
Abstract
The intrinsically disordered protein α-synuclein (aSN) is, in its fibrillated state, the main component of Lewy bodies-hallmarks of Parkinson's disease. Additional Lewy body components include glycosaminoglycans, including heparan sulfate proteoglycans. In humans, heparan sulfate has, in an age-dependent manner, shown increased levels of sulfation. Heparin, a highly sulfated glycosaminoglycan, is a relevant mimic for mature heparan sulfate and has been shown to influence aSN fibrillation. Here, we decompose the underlying properties of the interaction between heparin and aSN and the effect of heparin on fibrillation. Via the isolation of the first 61 residues of aSN, which lacked intrinsic fibrillation propensity, fibrillation could be induced by heparin, and access to the initial steps in fibrillation was possible. Here, structural changes with shifts from disorder via type I β-turns to β-sheets were revealed, correlating with an increase in the aSN1-61/heparin molar ratio. Fluorescence microscopy revealed that heparin and aSN1-61 co-exist in the final fibrils. We conclude that heparin can induce the fibrillation of aSN1-61, through binding to the N-terminal with an affinity that is higher in the truncated form of aSN. It does so by specifically modulating the structure of aSN via the formation of type I β-turn structures likely critical for triggering aSN fibrillation.
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Affiliation(s)
- Line K. Skaanning
- Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark; (L.K.S.); (T.S.); (J.H.M.); (S.B.); (B.V.)
| | - Angelo Santoro
- Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, Ole Maaløes vej 5, 2200 Copenhagen N, Denmark; (A.S.); (K.B.)
- Department of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Italy;
| | - Thomas Skamris
- Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark; (L.K.S.); (T.S.); (J.H.M.); (S.B.); (B.V.)
| | - Jacob Hertz Martinsen
- Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark; (L.K.S.); (T.S.); (J.H.M.); (S.B.); (B.V.)
- Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, Ole Maaløes vej 5, 2200 Copenhagen N, Denmark; (A.S.); (K.B.)
| | - Anna Maria D’Ursi
- Department of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Italy;
| | - Saskia Bucciarelli
- Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark; (L.K.S.); (T.S.); (J.H.M.); (S.B.); (B.V.)
| | - Bente Vestergaard
- Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark; (L.K.S.); (T.S.); (J.H.M.); (S.B.); (B.V.)
| | - Katrine Bugge
- Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, Ole Maaløes vej 5, 2200 Copenhagen N, Denmark; (A.S.); (K.B.)
| | - Annette Eva Langkilde
- Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark; (L.K.S.); (T.S.); (J.H.M.); (S.B.); (B.V.)
| | - Birthe B. Kragelund
- Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, Ole Maaløes vej 5, 2200 Copenhagen N, Denmark; (A.S.); (K.B.)
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21
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Deciphering the anti-Parkinson’s activity of sulphated polysaccharides from Chlamydomonas reinhardtii on the α-Synuclein mutants A30P, A53T, E46K, E57K and E35K. J Biochem 2019; 166:463-474. [DOI: 10.1093/jb/mvz064] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 07/23/2019] [Indexed: 01/18/2023] Open
Abstract
AbstractParkinsonism-linked mutations in alanine and glutamic acid residues of the pre-synaptic protein α-Synuclein (α-Syn) affect specific tertiary interactions essential for stability of the native state and make it prone to more aggregation. Many of the currently available drugs used for the treatment of Parkinson’s disease (PD) are not very effective and are associated with multiple side effects. Recently, marine algae have been reported to have sulphated polysaccharides which offers multiple pharmaceutical properties. With this background, we have isolated sulphated polysaccharides from Chlamydomonas reinhardtii (Cr-SPs) and investigated their effects on inhibition of fibrillation/aggregation of α-Syn mutants through a combination of spectroscopic and microscopic techniques. The kinetics of α-Syn fibrillation establishes that Cr-SPs are very effective in inhibiting fibrillation of α-Syn mutants. The morphological changes associated with the fibrillation/aggregation process have been monitored by transmission electron microscopy. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis gel image suggests that Cr-SPs increase the amount of soluble protein after completion of the fibrillation/aggregation process. The circular dichroism results showed that Cr-SPs efficiently delay the conversion of native protein into β-sheet-rich structures. Thus, the current work has considerable therapeutic implications towards deciphering the potential of Cr-SPs to act against PD and other protein aggregation-related disorders.
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22
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Computational insights into the role of α-strand/sheet in aggregation of α-synuclein. Sci Rep 2019; 9:59. [PMID: 30635607 PMCID: PMC6329781 DOI: 10.1038/s41598-018-37276-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 12/05/2018] [Indexed: 01/03/2023] Open
Abstract
The α-synuclein is a major component of amyloid fibrils found in Lewy bodies, the characteristic intracellular proteinaceous deposits which are pathological hallmarks of neurodegenerative diseases such as Parkinson’s disease (PD) and dementia. It is an intrinsically disordered protein that may undergo dramatic structural changes to form amyloid fibrils. Aggregation process from α-synuclein monomers to amyloid fibrils through oligomeric intermediates is considered as the disease-causative toxic mechanism. However, mechanism underlying aggregation is not well-known despite several attempts. To characterize the mechanism, we have explored the effects of pH and temperature on the structural properties of wild-type and mutant α-synuclein using molecular dynamics (MD) simulation technique. MD studies suggested that amyloid fibrils can grow by monomer. Conformational transformation of the natively unfolded protein into partially folded intermediate could be accountable for aggregation and fibrillation. An intermediate α-strand was observed in the hydrophobic non-amyloid-β component (NAC) region of α-synuclein that could proceed to α-sheet and initiate early assembly events. Water network around the intermediate was analyzed to determine its influence on the α-strand structure. Findings of this study provide novel insights into possible mechanism of α-synuclein aggregation and promising neuroprotective strategy that could aid alleviate PD and its symptoms.
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Van de Vondel E, Baatsen P, Van Elzen R, Lambeir AM, Keiderling TA, Herrebout WA, Johannessen C. Vibrational Circular Dichroism Sheds New Light on the Competitive Effects of Crowding and β-Synuclein on the Fibrillation Process of α-Synuclein. Biochemistry 2018; 57:5989-5995. [DOI: 10.1021/acs.biochem.8b00780] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Evelien Van de Vondel
- Molecular Spectroscopy Group, Department of Chemistry, University of Antwerp, 2020 Antwerp, Belgium
| | - Pieter Baatsen
- VIB & KU Leuven Center for Brain & Disease Research, 3000 Leuven, Belgium
- VIB & KU Leuven BioImaging Core, 9052 Ghent, Belgium
| | - Roos Van Elzen
- Laboratory of Medical Biochemistry, Department of Pharmacy, University of Antwerp, 2610 Wilrijk, Belgium
| | - Anne-Marie Lambeir
- Laboratory of Medical Biochemistry, Department of Pharmacy, University of Antwerp, 2610 Wilrijk, Belgium
| | - Timothy A. Keiderling
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois 60607, United States
| | - Wouter A. Herrebout
- Molecular Spectroscopy Group, Department of Chemistry, University of Antwerp, 2020 Antwerp, Belgium
| | - Christian Johannessen
- Molecular Spectroscopy Group, Department of Chemistry, University of Antwerp, 2020 Antwerp, Belgium
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Jain MK, Singh P, Roy S, Bhat R. Comparative Analysis of the Conformation, Aggregation, Interaction, and Fibril Morphologies of Human α-, β-, and γ-Synuclein Proteins. Biochemistry 2018; 57:3830-3848. [PMID: 29851342 DOI: 10.1021/acs.biochem.8b00343] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The human synuclein (syn) family is comprised of α-, β-, and γ-syn proteins. α-syn has the highest propensity for aggregation, and its aggregated forms accumulate in Lewy bodies (LB) and Lewy neurites, which are involved in Parkinson's disease (PD). β- and γ-syn are absent in LB, and their exact role is still enigmatic. β-syn does not form aggregates under physiological conditions (pH 7.4), while γ-syn is associated with neural and non-neural diseases like breast cancer. Because of their similar regional distribution in the brain, natively unfolded structure, and high degree of sequence homology, studying the effect of the environment on their conformation, interactions, fibrillation, and fibril morphologies has become important. Our studies show that high temperatures, low pH values, and high concentrations increase the rate of fibrillation of α- and γ-syn, while β-syn forms fibrils only at low pH. Fibril morphologies are strongly dependent on the immediate environment of the proteins. The high molar ratio of β-syn inhibits the fibrillation in α- and γ-syn. However, preformed seed fibrils of β- and γ-syn do not affect fibrillation of α-syn. Surface plasmon resonance data show that interactions between α- and β-syn, β- and γ-syn, and α- and γ-syn are weak to moderate in nature and can be physiologically significant in counteracting several adverse conditions in the cells that trigger their aggregation. These studies could be helpful in understanding collective human synuclein behavior in various protein environments and in the modulation of the homeostasis between β-syn and healthy versus corrupt α- and γ-syn that can potentially affect PD pathology.
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Affiliation(s)
- Manish Kumar Jain
- School of Biotechnology , Jawaharlal Nehru University , New Delhi 110 067 , India
| | - Priyanka Singh
- School of Biotechnology , Jawaharlal Nehru University , New Delhi 110 067 , India
| | - Sneha Roy
- School of Biotechnology , Jawaharlal Nehru University , New Delhi 110 067 , India
| | - Rajiv Bhat
- School of Biotechnology , Jawaharlal Nehru University , New Delhi 110 067 , India
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25
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Doherty CPA, Young LM, Karamanos TK, Smith HI, Jackson MP, Radford SE, Brockwell DJ. A peptide-display protein scaffold to facilitate single molecule force studies of aggregation-prone peptides. Protein Sci 2018; 27:1205-1217. [PMID: 29417650 PMCID: PMC6032367 DOI: 10.1002/pro.3386] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 02/05/2018] [Accepted: 02/05/2018] [Indexed: 01/12/2023]
Abstract
Protein aggregation is linked with the onset of several neurodegenerative disorders, including Parkinson's disease (PD), which is associated with the aggregation of α‐synuclein (αSyn). The structural mechanistic details of protein aggregation, including the nature of the earliest protein–protein interactions, remain elusive. In this study, we have used single molecule force spectroscopy (SMFS) to probe the first dimerization events of the central aggregation‐prone region of αSyn (residues 71–82) that may initiate aggregation. This region has been shown to be necessary for the aggregation of full length αSyn and is capable of forming amyloid fibrils in isolation. We demonstrate that the interaction of αSyn71‐82 peptides can be studied using SMFS when inserted into a loop of protein L, a mechanically strong and soluble scaffold protein that acts as a display system for SMFS studies. The corresponding fragment of the homolog protein γ‐synuclein (γSyn), which has a lower aggregation propensity, has also been studied here. The results from SMFS, together with native mass spectrometry and aggregation assays, demonstrate that the dimerization propensity of γSyn71‐82 is lower than that of αSyn71‐82, but that a mixed αSyn71‐82: γSyn71‐82 dimer forms with a similar propensity to the αSyn71‐82 homodimer, slowing amyloid formation. This work demonstrates the utility of a novel display method for SMFS studies of aggregation‐prone peptides, which would otherwise be difficult to study.
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Affiliation(s)
- Ciaran P A Doherty
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, United Kingdom.,School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Lydia M Young
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, United Kingdom.,School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Theodoros K Karamanos
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, United Kingdom.,School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Hugh I Smith
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, United Kingdom.,School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Matthew P Jackson
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, United Kingdom.,School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Sheena E Radford
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, United Kingdom.,School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - David J Brockwell
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, United Kingdom.,School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, United Kingdom
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26
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Molecular and Biological Compatibility with Host Alpha-Synuclein Influences Fibril Pathogenicity. Cell Rep 2018; 16:3373-3387. [PMID: 27653697 DOI: 10.1016/j.celrep.2016.08.053] [Citation(s) in RCA: 122] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 05/17/2016] [Accepted: 08/16/2016] [Indexed: 02/03/2023] Open
Abstract
The accumulation and propagation of misfolded α-synuclein (α-Syn) is a central feature of Parkinson's disease and other synucleinopathies. Molecular compatibility between a fibrillar seed and its native protein state is a major determinant of amyloid self-replication. We show that cross-seeded aggregation of human (Hu) and mouse (Ms) α-Syn is bidirectionally restricted. Although fibrils formed by Hu-Ms-α-Syn chimeric mutants can overcome this inhibition in cell-free systems, sequence homology poorly predicts their efficiency in inducing α-Syn pathology in primary neurons or after intracerebral injection into wild-type mice. Chimeric α-Syn fibrils demonstrate enhanced or reduced pathogenicities compared with wild-type Hu- or Ms-α-Syn fibrils. Furthermore, α-Syn mutants induced to polymerize by fibrillar seeds inherit the functional properties of their template, suggesting that transferable pathogenic and non-pathogenic states likely influence the initial engagement between exogenous α-Syn seeds and endogenous neuronal α-Syn. Thus, transmission of synucleinopathies is regulated by biological processes in addition to molecular compatibility.
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27
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Mochizuki H, Choong CJ, Masliah E. A refined concept: α-synuclein dysregulation disease. Neurochem Int 2018; 119:84-96. [PMID: 29305061 DOI: 10.1016/j.neuint.2017.12.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 12/21/2017] [Accepted: 12/29/2017] [Indexed: 12/23/2022]
Abstract
α-synuclein (αSyn) still remains a mysterious protein even two decades after SNCA encoding it was identified as the first causative gene of familial Parkinson's disease (PD). Accumulation of αSyn causes α-synucleinopathies including PD, dementia with Lewy bodies (DLB) and multiple system atrophy (MSA). Recent advances in therapeutic approaches offer new antibody-, vaccine-, antisense-oligonucleotide- and small molecule-based options to reduce αSyn protein levels and aggregates in patient's brain. Gathering research information of other neurological disease particularly Alzheimer's disease, recent disappointment of an experimental amyloid plaques busting antibody in clinical trials underscores the difficulty of treating people who show even mild dementia as damage in their brain may already be too extensive. Prodromal intervention to inhibit the accumulation of pathogenic protein may advantageously provide a better outcome. However, treatment prior to onset is not ethically justified as standard practice at present. In this review, we initiate a refined concept to define early pathogenic state of αSyn accumulation before occurrence of brain damage as a disease criterion for αSyn dysregulation disease.
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Affiliation(s)
- Hideki Mochizuki
- Department of Neurology, Graduate School of Medicine, Osaka University, Yamadaoka 2-2, Suita, Osaka, 565-0871, Japan.
| | - Chi-Jing Choong
- Department of Neurology, Graduate School of Medicine, Osaka University, Yamadaoka 2-2, Suita, Osaka, 565-0871, Japan
| | - Eliezer Masliah
- Department of Neurology, Graduate School of Medicine, Osaka University, Yamadaoka 2-2, Suita, Osaka, 565-0871, Japan
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28
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Abstract
A neurodegenerative disorder displaying an altered α-synuclein (αS) in the brain tissue is called α-synucleinopathy (αS-pathy) and incorporates clinical entities such as Parkinson disease (PD), PD with dementia, dementia with Lewy bodies, and multiple-system atrophy. Neuroradiologic techniques visualizing αS pathology in the brain or assays of αS in the cerebrospinal fluid or blood are probably available and will be implemented in the near future but currently the definite diagnosis of αS-pathy relies on a postmortem examination of the brain. Since the 1980s immunohistochemical technique based on the use of antibodies directed to proteins of interest has become a method of choice for neuropathologic diagnosis. Furthermore, since the 1990s it has been acknowledged that progressions of most neurodegenerative pathologies follow a certain predictable time-related neuroanatomic distribution. Currently, for Lewy body disease, two staging techniques are commonly used: McKeith and Braak staging. Thus, the neuropathologic diagnosis of a αS-pathy is based on detection of altered αS in the tissue and registration of the neuroanatomic distribution of this alteration in the brain. The clinicopathologic correlation is not absolute due to the quite frequent observation of incidental and concomitant αS pathology.
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Affiliation(s)
- Irina Alafuzoff
- Department of Immunology, Genetics and Pathology, Uppsala University, Department of Pathology, Uppsala University Hospital and Rudbeck Laboratory, Uppsala, Sweden.
| | - Päivi Hartikainen
- Department of Neurology, Institute of Clinical Medicine, University of Eastern Finland and Department of Neurology, Kuopio University Hospital, Kuopio, Finland
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29
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The ER retention protein RER1 promotes alpha-synuclein degradation via the proteasome. PLoS One 2017; 12:e0184262. [PMID: 28877262 PMCID: PMC5587320 DOI: 10.1371/journal.pone.0184262] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Accepted: 08/21/2017] [Indexed: 11/19/2022] Open
Abstract
Abnormal accumulation of α-synuclein (αSyn) has been linked to endoplasmic-reticulum (ER) stress, defective intracellular protein/vesicle trafficking, and cytotoxicity. Targeting factors involved in ER-related protein processing and trafficking may, therefore, be a key to modulating αSyn levels and associated toxicity. Recently retention in endoplasmic reticulum 1 (RER1) has been identified as an important ER retrieval/retention factor for Alzheimer's disease proteins and negatively regulates amyloid-β peptide levels. Here, we hypothesized that RER1 might also play an important role in retention/retrieval of αSyn and mediate levels. We expressed RER1 and a C-terminal mutant RER1Δ25, which lacks the ER retention/retrieval function, in HEK293 and H4 neuroglioma cells. RER1 overexpression significantly decreased levels of both wild type and A30P, A53T, and E46K disease causal mutants of αSyn, whereas the RER1Δ25 mutant had a significantly attenuated effect on αSyn. RER1 effects were specific to αSyn and had little to no effect on either βSyn or the Δ71-82 αSyn mutant, which both lack the NAC domain sequence critical for synuclein fibrillization. Tests with proteasomal and macroautophagy inhibitors further demonstrate that RER1 effects on αSyn are primarily mediated through the ubiquitin-proteasome system. RER1 also appears to interact with the ubiquitin ligase NEDD4. RER1 in human diseased brain tissues co-localizes with αSyn-positive Lewy bodies. Together, these findings provide evidence that RER1 is a novel and potential important mediator of elevated αSyn levels. Further investigation of the mechanism of RER1 and downstream effectors on αSyn may yield novel therapeutic targets for modulation in Parkinson disease and related synucleinopathies.
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30
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Yakupova EI, Vikhlyantsev IM, Bobyleva LG, Penkov NV, Timchenko AA, Timchenko MA, Enin GA, Khutzian SS, Selivanova OM, Bobylev AG. Different amyloid aggregation of smooth muscles titin in vitro. J Biomol Struct Dyn 2017; 36:2237-2248. [PMID: 28661225 DOI: 10.1080/07391102.2017.1348988] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
A comparative study of amyloid properties of the aggregates of smooth muscle titin (SMT) from chicken gizzard was carried out. These aggregates were formed in two solutions: 0.15 M glycine-KOH, pH 7.2-7.4 (SMT(Gly)) and 0.2 M KCl, 10 mM imidazole, pH 7.0 (SMT(KCl)). Electron microscopy data showed that SMT aggregates has an amorphous structure in both cases. The results of atomic-force microscopy demonstrated slight differences in morphology in two types of aggregates. The SMT(Gly) aggregates were represented as branching chains, composed of spherical aggregates approximately 300-500 nm in diameter and up to 35 nm in height. The SMT(KCl) aggregates formed sponge-like structures with strands of 8-10 nm in height. Structural analysis of SMT aggregates by X-ray diffraction revealed the presence of cross-β-sheet structure in the samples under study. In the presence of SMT(Gly) aggregates, thioflavine T fluorescence intensity was higher (~3-fold times) compared with that in the presence of SMT(KCl) aggregates. Congo red-stained SMT(Gly) aggregates had yellow to apple-green birefringence under polarized light, which was not observed for SMT(KCl) aggregates. Dynamic light scattering data showed the similar rate of aggregation for both types of aggregates, though SMT(KCl) aggregates were able to partially disaggregate under increased ionic strength of the solution. The ability of SMT to aggregation followed by disaggregation may be functionally significant in the cell.
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Affiliation(s)
- Elmira I Yakupova
- a Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences , Pushchino , Moscow Region 142290 , Russia.,b Pushchino State Institute of Natural Sciences , Pushchino , Moscow Region 142290 , Russia
| | - Ivan M Vikhlyantsev
- a Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences , Pushchino , Moscow Region 142290 , Russia.,b Pushchino State Institute of Natural Sciences , Pushchino , Moscow Region 142290 , Russia
| | - Liya G Bobyleva
- a Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences , Pushchino , Moscow Region 142290 , Russia
| | - Nikita V Penkov
- c Institute of Cell Biophysics, Russian Academy of Sciences , Pushchino , Moscow Region 142290 , Russia
| | - Alexander A Timchenko
- d Institute of Protein Research, Russian Academy of Sciences , Pushchino , Moscow Region 142290 , Russia
| | - Maria A Timchenko
- a Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences , Pushchino , Moscow Region 142290 , Russia
| | - Gennady A Enin
- d Institute of Protein Research, Russian Academy of Sciences , Pushchino , Moscow Region 142290 , Russia
| | - Sergei S Khutzian
- a Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences , Pushchino , Moscow Region 142290 , Russia.,c Institute of Cell Biophysics, Russian Academy of Sciences , Pushchino , Moscow Region 142290 , Russia
| | - Olga M Selivanova
- d Institute of Protein Research, Russian Academy of Sciences , Pushchino , Moscow Region 142290 , Russia
| | - Alexander G Bobylev
- a Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences , Pushchino , Moscow Region 142290 , Russia.,b Pushchino State Institute of Natural Sciences , Pushchino , Moscow Region 142290 , Russia
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31
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Roeters SJ, Iyer A, Pletikapić G, Kogan V, Subramaniam V, Woutersen S. Evidence for Intramolecular Antiparallel Beta-Sheet Structure in Alpha-Synuclein Fibrils from a Combination of Two-Dimensional Infrared Spectroscopy and Atomic Force Microscopy. Sci Rep 2017; 7:41051. [PMID: 28112214 PMCID: PMC5253669 DOI: 10.1038/srep41051] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 12/12/2016] [Indexed: 12/13/2022] Open
Abstract
The aggregation of the intrinsically disordered protein alpha-synuclein (αS) into amyloid fibrils is thought to play a central role in the pathology of Parkinson’s disease. Using a combination of techniques (AFM, UV-CD, XRD, and amide-I 1D- and 2D-IR spectroscopy) we show that the structure of αS fibrils varies as a function of ionic strength: fibrils aggregated in low ionic-strength buffers ([NaCl] ≤ 25 mM) have a significantly different structure than fibrils grown in higher ionic-strength buffers. The observations for fibrils aggregated in low-salt buffers are consistent with an extended conformation of αS molecules, forming hydrogen-bonded intermolecular β-sheets that are loosely packed in a parallel fashion. For fibrils aggregated in high-salt buffers (including those prepared in buffers with a physiological salt concentration) the measurements are consistent with αS molecules in a more tightly-packed, antiparallel intramolecular conformation, and suggest a structure characterized by two twisting stacks of approximately five hydrogen-bonded intermolecular β-sheets each. We find evidence that the high-frequency peak in the amide-I spectrum of αS fibrils involves a normal mode that differs fundamentally from the canonical high-frequency antiparallel β-sheet mode. The high sensitivity of the fibril structure to the ionic strength might form the basis of differences in αS-related pathologies.
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Affiliation(s)
- Steven J Roeters
- Van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Aditya Iyer
- Nanoscale Biophysics Group, FOM Institute AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
| | - Galja Pletikapić
- Nanoscale Biophysics Group, FOM Institute AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
| | - Vladimir Kogan
- Dannalab BV, Wethouder Beversstraat 185, 7543 BK Enschede, The Netherlands
| | - Vinod Subramaniam
- Nanoscale Biophysics Group, FOM Institute AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands.,Vrije Universiteit Amsterdam, De Boelelaan 1105, 1081 HV Amsterdam, The Netherlands
| | - Sander Woutersen
- Van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
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32
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Landeck N, Buck K, Kirik D. Toxic effects of human and rodent variants of alpha-synuclein in vivo. Eur J Neurosci 2017; 45:536-547. [PMID: 27893183 DOI: 10.1111/ejn.13493] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 11/10/2016] [Accepted: 11/23/2016] [Indexed: 12/11/2022]
Abstract
In Parkinson's disease, abnormal alpha-synuclein (asyn) accumulation leads to the formation of soluble oligomeric species thought to be toxic to cells as well as intraneuronal inclusions. To date, the precise mechanisms leading to aggregation of asyn in the brain is not well-understood. Previous studies in yeast, drosophila, and transgenic mice suggested that a non-A beta component depleted version of human asyn [h-asyn(D70-83)] or human beta-synuclein (h-bsyn), naturally lacking this centrally located hydrophobic region, are less prone to form aggregates in vitro and are expected to be less toxic compared to h-asyn in vivo, although not all experimental studies unequivocally support the latter view. To address this outstanding issue, we directly compared the neurotoxicity of human asyn against that of h-asyn(D70-83), h-bsyn as well as rat asyn using an adeno-associated viral vector to express these proteins in a dose-response study where the vector load was varied over two orders of magnitude. By quantifying the neurodegeneration of rat substantia nigra dopamine neurons here we show that h-asyn, h-bsyn, and h-asyn(D70-83) display comparable neurotoxicity across the vector doses tested. On the other hand, rat asyn and GFP control vectors displayed a different profile, where no detectable neurodegeneration was seen except at the highest vector titer. Thus, the two main conclusions of our study are that (i) deletion of the central hydrophobic region in h-asyn is not sufficient to alter its neurotoxic properties and (ii) expression of the widely used GFP control protein can cause measurable neurodegeneration at high titers.
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Affiliation(s)
- Natalie Landeck
- Brain Repair and Imaging in Neural Systems (BRAINS) Unit, Department of Experimental Medical Science, Lund University, BMC D11, Lund, 22184, Sweden
| | - Kerstin Buck
- Brain Repair and Imaging in Neural Systems (BRAINS) Unit, Department of Experimental Medical Science, Lund University, BMC D11, Lund, 22184, Sweden
| | - Deniz Kirik
- Brain Repair and Imaging in Neural Systems (BRAINS) Unit, Department of Experimental Medical Science, Lund University, BMC D11, Lund, 22184, Sweden
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33
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Sanjeev A, Sahu RK, Mattaparthi VSK. Potential of mean force and molecular dynamics study on the transient interactions between α and β synuclein that drive inhibition of α-synuclein aggregation. J Biomol Struct Dyn 2016; 35:3342-3353. [DOI: 10.1080/07391102.2016.1254119] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Airy Sanjeev
- Molecular Modelling and Simulation Lab, Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur 784 028, Assam, India
| | - Ravi Kumar Sahu
- Molecular Modelling and Simulation Lab, Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur 784 028, Assam, India
| | - Venkata Satish Kumar Mattaparthi
- Molecular Modelling and Simulation Lab, Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur 784 028, Assam, India
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34
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Abstract
α-Synuclein, which is present as a small, soluble, cytosolic protein in healthy subjects, is converted to amyloid-like fibrils in diseases such as Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). Bulk synthesis of purified α-synuclein has made it more convenient to study the nature of the normal protein and the mechanism of its conversion to an abnormal form in vitro and in vivo. Synthetic α-synuclein fibrils and pathological α-synuclein from diseased brains can act as triggers to convert normal α-synuclein to an abnormal form via prion-like mechanisms. In this article, we describe the experimental pathologies of α-synuclein both in vitro and in vivo in human and animal models. Prion-like spreading of abnormal α-synuclein from cell to cell can account for the progression of these α-synucleinopathies.
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Affiliation(s)
- Masato Hasegawa
- Department of Neuropathology and Cell Biology, Dementia Research Project, Tokyo Metropolitan Institute of Medical Science, Setagaya-ku, Tokyo 156-8506, Japan
| | - Takashi Nonaka
- Department of Neuropathology and Cell Biology, Dementia Research Project, Tokyo Metropolitan Institute of Medical Science, Setagaya-ku, Tokyo 156-8506, Japan
| | - Masami Masuda-Suzukake
- Department of Neuropathology and Cell Biology, Dementia Research Project, Tokyo Metropolitan Institute of Medical Science, Setagaya-ku, Tokyo 156-8506, Japan
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35
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Toni M, Cioni C, De Angelis F, di Patti MCB. Synuclein expression in the lizard Anolis carolinensis. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2016; 202:577-95. [DOI: 10.1007/s00359-016-1108-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 06/09/2016] [Accepted: 06/26/2016] [Indexed: 12/30/2022]
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36
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Mane JY, Stepanova M. Understanding the dynamics of monomeric, dimeric, and tetrameric α-synuclein structures in water. FEBS Open Bio 2016; 6:666-86. [PMID: 27398307 PMCID: PMC4932447 DOI: 10.1002/2211-5463.12069] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 04/05/2016] [Accepted: 04/06/2016] [Indexed: 01/20/2023] Open
Abstract
Human α‐synuclein (αS) is an intrinsically disordered protein associated with Parkinson's disease. Molecular mechanisms of corruptive misfolding and aggregation of αS resulting in the disease, as well as the structure and other properties of the corresponding oligomers are not entirely understood yet, preventing the development of efficient therapies. In this study, we investigate the folding dynamics of initially unfolded hypothetical αS constructs in water using all‐atom molecular dynamics simulations. We also employ the novel essential collective dynamics method to analyze the results obtained from the simulations. Our comparative analysis of monomeric, dimeric, and tetrameric αS models reveals pronounced differences in their structure and stability, emphasizing the importance of small oligomers, particularly dimers, in the process of misfolding.
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Affiliation(s)
- Jonathan Y Mane
- Department of Electrical and Computer Engineering University of Alberta Edmonton Canada; National Institute for Nanotechnology National Research Council Canada Edmonton Canada
| | - Maria Stepanova
- Department of Electrical and Computer Engineering University of Alberta Edmonton Canada; National Institute for Nanotechnology National Research Council Canada Edmonton Canada; Department of Physics, Astronomy, and Materials Science Missouri State University Springfield MO USA
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37
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Brandel JP, Corbillé AG, Derkinderen P, Haïk S. [Is Parkinson's disease a prion disease?]. Rev Neurol (Paris) 2015; 171:812-24. [PMID: 26563663 PMCID: PMC7111738 DOI: 10.1016/j.neurol.2015.10.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 10/15/2015] [Accepted: 10/16/2015] [Indexed: 02/07/2023]
Abstract
The accumulation of a specific protein in aggregated form is a common phenomenon in human neurodegenerative diseases. In Parkinson's disease, this protein is α-synuclein which is a neuronal protein of 143 amino acids. With a monomeric conformation in solution, it also has a natural capacity to aggregate into amyloid structures (dimers, oligomers, fibrils and Lewy bodies or neurites). It therefore fulfils the characteristics of a prion protein (different conformations, seeding and spreading). In vitro and in vivo experimental evidence in transgenic and wild animals indicates a prion-like propagation of Parkinson's disease. The sequential and predictive distribution of α-synuclein demonstrated by Braak et al. and its correlation with non-motor signs are consistent with the prion-like progression. Although the triggering factor causing the misfolding and aggregation of the target protein is unknown, Parkinson's disease is a highly relevant model for the study of these mechanisms and also to test specific treatments targeting the assemblies of α-synuclein and propagation from pre-motor phase of the disease. Despite this prion-like progression, there is currently no argument indicating a risk of human transmission of Parkinson's disease.
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Affiliation(s)
- J-P Brandel
- Inserm U 1127, CNRS UMR 7225, Sorbonne universités, UPMC University Paris 06 UMR S 1127, institut du cerveau et de la mœlle épinière, ICM, 75013 Paris, France; Cellule nationale de référence des maladies de Creutzfeldt-Jakob, groupe hospitalier Pitié-Salpêtrière, AP-HP, 47-83, boulevard de l'Hôpital, 75651 Paris cedex 13, France; Centre national de référence des agents transmissibles non conventionnels, 75013 Paris, France; Unité James-Parkinson, Fondation ophtalmologique Rothschild, 75019 Paris, France.
| | - A-G Corbillé
- Département de neurologie, CHU de Nantes, 44093 Nantes, France; Inserm, U913, 44093 Nantes, France
| | - P Derkinderen
- Département de neurologie, CHU de Nantes, 44093 Nantes, France; Inserm, U913, 44093 Nantes, France
| | - S Haïk
- Inserm U 1127, CNRS UMR 7225, Sorbonne universités, UPMC University Paris 06 UMR S 1127, institut du cerveau et de la mœlle épinière, ICM, 75013 Paris, France; Cellule nationale de référence des maladies de Creutzfeldt-Jakob, groupe hospitalier Pitié-Salpêtrière, AP-HP, 47-83, boulevard de l'Hôpital, 75651 Paris cedex 13, France; Centre national de référence des agents transmissibles non conventionnels, 75013 Paris, France
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38
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Rodriguez JA, Ivanova MI, Sawaya MR, Cascio D, Reyes FE, Shi D, Sangwan S, Guenther EL, Johnson LM, Zhang M, Jiang L, Arbing MA, Nannenga BL, Hattne J, Whitelegge J, Brewster AS, Messerschmidt M, Boutet S, Sauter NK, Gonen T, Eisenberg DS. Structure of the toxic core of α-synuclein from invisible crystals. Nature 2015; 525:486-90. [PMID: 26352473 DOI: 10.1038/nature15368] [Citation(s) in RCA: 444] [Impact Index Per Article: 49.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Accepted: 08/13/2015] [Indexed: 12/18/2022]
Abstract
The protein α-synuclein is the main component of Lewy bodies, the neuron-associated aggregates seen in Parkinson disease and other neurodegenerative pathologies. An 11-residue segment, which we term NACore, appears to be responsible for amyloid formation and cytotoxicity of human α-synuclein. Here we describe crystals of NACore that have dimensions smaller than the wavelength of visible light and thus are invisible by optical microscopy. As the crystals are thousands of times too small for structure determination by synchrotron X-ray diffraction, we use micro-electron diffraction to determine the structure at atomic resolution. The 1.4 Å resolution structure demonstrates that this method can determine previously unknown protein structures and here yields, to our knowledge, the highest resolution achieved by any cryo-electron microscopy method to date. The structure exhibits protofibrils built of pairs of face-to-face β-sheets. X-ray fibre diffraction patterns show the similarity of NACore to toxic fibrils of full-length α-synuclein. The NACore structure, together with that of a second segment, inspires a model for most of the ordered portion of the toxic, full-length α-synuclein fibril, presenting opportunities for the design of inhibitors of α-synuclein fibrils.
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Affiliation(s)
- Jose A Rodriguez
- Howard Hughes Medical Institute, UCLA-DOE Institute, Departments of Biological Chemistry and Chemistry and Biochemistry, Box 951570, UCLA, Los Angeles, California 90095-1570, USA
| | - Magdalena I Ivanova
- Howard Hughes Medical Institute, UCLA-DOE Institute, Departments of Biological Chemistry and Chemistry and Biochemistry, Box 951570, UCLA, Los Angeles, California 90095-1570, USA
| | - Michael R Sawaya
- Howard Hughes Medical Institute, UCLA-DOE Institute, Departments of Biological Chemistry and Chemistry and Biochemistry, Box 951570, UCLA, Los Angeles, California 90095-1570, USA
| | - Duilio Cascio
- Howard Hughes Medical Institute, UCLA-DOE Institute, Departments of Biological Chemistry and Chemistry and Biochemistry, Box 951570, UCLA, Los Angeles, California 90095-1570, USA
| | - Francis E Reyes
- Howard Hughes Medical Institute, Janelia Research Campus, 19700 Helix Drive, Ashburn, Virginia 20147, USA
| | - Dan Shi
- Howard Hughes Medical Institute, Janelia Research Campus, 19700 Helix Drive, Ashburn, Virginia 20147, USA
| | - Smriti Sangwan
- Howard Hughes Medical Institute, UCLA-DOE Institute, Departments of Biological Chemistry and Chemistry and Biochemistry, Box 951570, UCLA, Los Angeles, California 90095-1570, USA
| | - Elizabeth L Guenther
- Howard Hughes Medical Institute, UCLA-DOE Institute, Departments of Biological Chemistry and Chemistry and Biochemistry, Box 951570, UCLA, Los Angeles, California 90095-1570, USA
| | - Lisa M Johnson
- Howard Hughes Medical Institute, UCLA-DOE Institute, Departments of Biological Chemistry and Chemistry and Biochemistry, Box 951570, UCLA, Los Angeles, California 90095-1570, USA
| | - Meng Zhang
- Howard Hughes Medical Institute, UCLA-DOE Institute, Departments of Biological Chemistry and Chemistry and Biochemistry, Box 951570, UCLA, Los Angeles, California 90095-1570, USA
| | - Lin Jiang
- Howard Hughes Medical Institute, UCLA-DOE Institute, Departments of Biological Chemistry and Chemistry and Biochemistry, Box 951570, UCLA, Los Angeles, California 90095-1570, USA
| | - Mark A Arbing
- Howard Hughes Medical Institute, UCLA-DOE Institute, Departments of Biological Chemistry and Chemistry and Biochemistry, Box 951570, UCLA, Los Angeles, California 90095-1570, USA
| | - Brent L Nannenga
- Howard Hughes Medical Institute, Janelia Research Campus, 19700 Helix Drive, Ashburn, Virginia 20147, USA
| | - Johan Hattne
- Howard Hughes Medical Institute, Janelia Research Campus, 19700 Helix Drive, Ashburn, Virginia 20147, USA
| | - Julian Whitelegge
- Box 42, NPI-Semel Institute, 760 Westwood Plaza, UCLA, Los Angeles, California 90024, USA
| | - Aaron S Brewster
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Marc Messerschmidt
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Sébastien Boutet
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Nicholas K Sauter
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Tamir Gonen
- Howard Hughes Medical Institute, Janelia Research Campus, 19700 Helix Drive, Ashburn, Virginia 20147, USA
| | - David S Eisenberg
- Howard Hughes Medical Institute, UCLA-DOE Institute, Departments of Biological Chemistry and Chemistry and Biochemistry, Box 951570, UCLA, Los Angeles, California 90095-1570, USA
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Dimerization propensities of Synucleins are not predictive for Synuclein aggregation. Biochim Biophys Acta Mol Basis Dis 2015; 1852:1658-64. [DOI: 10.1016/j.bbadis.2015.05.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Revised: 04/07/2015] [Accepted: 05/02/2015] [Indexed: 12/13/2022]
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Fibril growth and seeding capacity play key roles in α-synuclein-mediated apoptotic cell death. Cell Death Differ 2015; 22:2107-22. [PMID: 26138444 DOI: 10.1038/cdd.2015.79] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 04/30/2015] [Accepted: 05/06/2015] [Indexed: 02/08/2023] Open
Abstract
The role of extracellular α-synuclein (α-syn) in the initiation and the spreading of neurodegeneration in Parkinson's disease (PD) has been studied extensively over the past 10 years. However, the nature of the α-syn toxic species and the molecular mechanisms by which they may contribute to neuronal cell loss remain controversial. In this study, we show that fully characterized recombinant monomeric, fibrillar or stabilized forms of oligomeric α-syn do not trigger significant cell death when added individually to neuroblastoma cell lines. However, a mixture of preformed fibrils (PFFs) with monomeric α-syn becomes toxic under conditions that promote their growth and amyloid formation. In hippocampal primary neurons and ex vivo hippocampal slice cultures, α-syn PFFs are capable of inducing a moderate toxicity over time that is greatly exacerbated upon promoting fibril growth by addition of monomeric α-syn. The causal relationship between α-syn aggregation and cellular toxicity was further investigated by assessing the effect of inhibiting fibrillization on α-syn-induced cell death. Remarkably, our data show that blocking fibril growth by treatment with known pharmacological inhibitor of α-syn fibrillization (Tolcapone) or replacing monomeric α-syn by monomeric β-synuclein in α-syn mixture composition prevent α-syn-induced toxicity in both neuroblastoma cell lines and hippocampal primary neurons. We demonstrate that exogenously added α-syn fibrils bind to the plasma membrane and serve as nucleation sites for the formation of α-syn fibrils and promote the accumulation and internalization of these aggregates that in turn activate both the extrinsic and intrinsic apoptotic cell death pathways in our cellular models. Our results support the hypothesis that ongoing aggregation and fibrillization of extracellular α-syn play central roles in α-syn extracellular toxicity, and suggest that inhibiting fibril growth and seeding capacity constitute a viable strategy for protecting against α-syn-induced toxicity and slowing the progression of neurodegeneration in PD and other synucleinopathies.
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Krassnig S, Schweinzer C, Taub N, Havas D, Auer E, Flunkert S, Schreibmayer W, Hutter-Paier B, Windisch M. Influence of Lentiviral β-Synuclein Overexpression in the Hippocampus of a Transgenic Mouse Model of Alzheimer's Disease on Amyloid Precursor Protein Metabolism and Pathology. NEURODEGENER DIS 2015; 15:243-57. [PMID: 26111745 DOI: 10.1159/000430952] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2014] [Accepted: 04/26/2015] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND β-Synuclein (β-Syn) is a member of the highly homologous synuclein protein family. The most prominent family member, α-synuclein (α-Syn), abnormally accumulates in so-called Lewy bodies, one of the major pathological hallmarks of α-synucleinopathies. Notably, parts of the peptide backbone, called the nonamyloid component, are also found in amyloid plaques. However, β-Syn seems to have beneficial effects by reducing α-Syn aggregation, and amyloid antiaggregatory activity has been described. OBJECTIVE The aim of the study was to analyze if wild-type β-Syn can counteract functional and pathological changes in a murine Alzheimer model over different time periods. METHODS At the onset of pathology, lentiviral particles expressing human β-Syn were injected into the hippocampus of transgenic mice overexpressing human amyloid precursor protein with Swedish and London mutations (APPSL). An empty vector served as the control. Behavioral analyses were performed 1, 3 and 6 months after injection followed by biochemical and histological examinations of brain samples. RESULTS β-Syn expression was locally concentrated and rather modest, but nevertheless changed its effect on APP expression and plaque load in a time- and concentration-dependent manner. Interestingly, the phosphorylation of glycogen synthase kinase 3 beta was enhanced in APPSL mice expressing human β-Syn, but an inverse trend was observed in wild-type animals. CONCLUSION The initially reported beneficial effects of β-Syn could be partially reproduced, but locally elevated levels of β-Syn might also cause neurodegeneration. To enlighten the controversial pathological mechanism of β-Syn, further examinations considering the relationship between concentration and exposure time of β-Syn are needed.
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42
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The Role of α-Synuclein and LRRK2 in Tau Phosphorylation. PARKINSONS DISEASE 2015; 2015:734746. [PMID: 25977830 PMCID: PMC4419261 DOI: 10.1155/2015/734746] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/25/2014] [Revised: 04/02/2015] [Accepted: 04/02/2015] [Indexed: 01/08/2023]
Abstract
There is now a considerable body of experimental evidence that Parkinson's disease arises through physiological interaction of causative molecules, leading to tau pathology. In this review, we discuss the physiological role of α-synuclein and LRRK2 in the abnormal phosphorylation of tau. In addition, as recent reports have indicated that heat shock proteins- (HSPs-) inducing drugs can help to ameliorate neurodegenerative diseases associated with tau pathology, we also discuss therapeutic strategies for PD focusing on inhibition of α-synuclein- and LRRK2-associated tau phosphorylation by HSPs.
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Peters OM, Shelkovnikova T, Highley JR, Cooper-Knock J, Hortobágyi T, Troakes C, Ninkina N, Buchman VL. Gamma-synuclein pathology in amyotrophic lateral sclerosis. Ann Clin Transl Neurol 2014; 2:29-37. [PMID: 25642432 PMCID: PMC4301672 DOI: 10.1002/acn3.143] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Revised: 10/16/2014] [Accepted: 10/17/2014] [Indexed: 12/12/2022] Open
Abstract
Objective The prominent histopathological feature of the amyotrophic lateral sclerosis (ALS) is the presence of intracellular inclusions in degenerating neurons and their axons. The appearance and localization of these pathological structures depend on an aggregated protein that forms their scaffold. We investigated if γ-synuclein, an aggregation-prone protein highly expressed in healthy motor neurons, and predominantly localized in their axons and synaptic terminals is involved in ALS pathology. Methods Immunostaining of histological sections and sequential protein extraction from postmortem neural samples followed by immunoblotting. Results Immunohistochemical screening revealed a subset of sporadic (9 of 31) and familial (8 of 23) ALS cases with a novel type of pathology characterized by the accumulation of γ-synuclein in distinct profiles within the dorsolateral column. Sequential fractionation of proteins from the spinal cord tissues revealed detergent-insoluble γ-synuclein species specifically in the dorsolateral corticospinal tracts of a ALS patient with γ-synuclein-positive profiles in this region. These profiles are negative for protein markers commonly found in pathological inclusions in the spinal cord of ALS patients and most probably represent degenerated axons of upper motor neurons that have lost their neurofilaments. A subset of these profiles was found in association with phagocytic cells positive for Mac-2/Galectin-3. A smaller subset of studied ALS cases (4 of 54) contained large cytoplasmic inclusions in the cell body of remaining spinal motor neurons. Interpretation Our observations suggest that pathological aggregation of γ-synuclein might contribute to the pathogenesis of ALS.
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Affiliation(s)
- Owen M Peters
- School of Biosciences, Cardiff University Museum Avenue, Cardiff, CF10 3AX, United Kingdom
| | - Tatyana Shelkovnikova
- School of Biosciences, Cardiff University Museum Avenue, Cardiff, CF10 3AX, United Kingdom
| | - John Robin Highley
- The Sheffield Institute for Translational Neuroscience 385A Glossop Road, Sheffield, S10 2HQ, United Kingdom
| | - Johnathan Cooper-Knock
- The Sheffield Institute for Translational Neuroscience 385A Glossop Road, Sheffield, S10 2HQ, United Kingdom
| | - Tibor Hortobágyi
- Department of Clinical Neuroscience and MRC London Neurodegenerative Diseases Brain Bank, Institute of Psychiatry, King's College London De Crespigny Park, London, SE5 8AF, United Kingdom
| | - Claire Troakes
- Department of Clinical Neuroscience and MRC London Neurodegenerative Diseases Brain Bank, Institute of Psychiatry, King's College London De Crespigny Park, London, SE5 8AF, United Kingdom
| | - Natalia Ninkina
- School of Biosciences, Cardiff University Museum Avenue, Cardiff, CF10 3AX, United Kingdom ; Institute of General Pathology and Pathophysiology of Russian Academy of Medical Science 8 Baltijskaya str, Moscow, 125315, Russia
| | - Vladimir L Buchman
- School of Biosciences, Cardiff University Museum Avenue, Cardiff, CF10 3AX, United Kingdom
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44
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Allison JR, Rivers RC, Christodoulou JC, Vendruscolo M, Dobson CM. A relationship between the transient structure in the monomeric state and the aggregation propensities of α-synuclein and β-synuclein. Biochemistry 2014; 53:7170-83. [PMID: 25389903 PMCID: PMC4245978 DOI: 10.1021/bi5009326] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 10/25/2014] [Indexed: 12/02/2022]
Abstract
α-Synuclein is an intrinsically disordered protein whose aggregation is implicated in Parkinson's disease. A second member of the synuclein family, β-synuclein, shares significant sequence similarity with α-synuclein but is much more resistant to aggregation. β-Synuclein is missing an 11-residue stretch in the central non-β-amyloid component region that forms the core of α-synuclein amyloid fibrils, yet insertion of these residues into β-synuclein to produce the βSHC construct does not markedly increase the aggregation propensity. To investigate the structural basis of these different behaviors, quantitative nuclear magnetic resonance data, in the form of paramagnetic relaxation enhancement-derived interatomic distances, are combined with molecular dynamics simulations to generate ensembles of structures representative of the solution states of α-synuclein, β-synuclein, and βSHC. Comparison of these ensembles reveals that the differing aggregation propensities of α-synuclein and β-synuclein are associated with differences in the degree of residual structure in the C-terminus coupled to the shorter separation between the N- and C-termini in β-synuclein and βSHC, making protective intramolecular contacts more likely.
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Affiliation(s)
| | | | | | - Michele Vendruscolo
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K.
| | - Christopher M. Dobson
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K.
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Bédard L, Lefèvre T, Morin-Michaud É, Auger M. Besides Fibrillization: Putative Role of the Peptide Fragment 71–82 on the Structural and Assembly Behavior of α-Synuclein. Biochemistry 2014; 53:6463-72. [DOI: 10.1021/bi5008707] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Laurie Bédard
- Department of Chemistry,
Regroupement Québécois de Recherche sur la Fonction,
la Structure et l’Ingénierie des Protéines (PROTEO),
Centre de Recherche sur les Matériaux Avancés (CERMA),
Centre Québécois sur les Matériaux Fonctionnels
(CQMF), Université Laval, Québec, Québec G1V 0A6, Canada
| | - Thierry Lefèvre
- Department of Chemistry,
Regroupement Québécois de Recherche sur la Fonction,
la Structure et l’Ingénierie des Protéines (PROTEO),
Centre de Recherche sur les Matériaux Avancés (CERMA),
Centre Québécois sur les Matériaux Fonctionnels
(CQMF), Université Laval, Québec, Québec G1V 0A6, Canada
| | - Émilie Morin-Michaud
- Department of Chemistry,
Regroupement Québécois de Recherche sur la Fonction,
la Structure et l’Ingénierie des Protéines (PROTEO),
Centre de Recherche sur les Matériaux Avancés (CERMA),
Centre Québécois sur les Matériaux Fonctionnels
(CQMF), Université Laval, Québec, Québec G1V 0A6, Canada
| | - Michèle Auger
- Department of Chemistry,
Regroupement Québécois de Recherche sur la Fonction,
la Structure et l’Ingénierie des Protéines (PROTEO),
Centre de Recherche sur les Matériaux Avancés (CERMA),
Centre Québécois sur les Matériaux Fonctionnels
(CQMF), Université Laval, Québec, Québec G1V 0A6, Canada
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46
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Brodie NI, Makepeace KAT, Petrotchenko EV, Borchers CH. Isotopically-coded short-range hetero-bifunctional photo-reactive crosslinkers for studying protein structure. J Proteomics 2014; 118:12-20. [PMID: 25192908 DOI: 10.1016/j.jprot.2014.08.012] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2014] [Revised: 08/19/2014] [Accepted: 08/23/2014] [Indexed: 12/20/2022]
Abstract
UNLABELLED The resolution and the fidelity of a protein structural model, constructed using crosslinking data, is dependent on the crosslinking distance constraints. Most of the popular amine-reactive NHS-ester crosslinkers are limited in their capacity to provide short distance constraints because of the rarity of lysine residues occurring in close proximity in the protein structure. To solve this problem, hetero-bifunctional crosslinkers containing both a photo-reactive functional group and an NHS-ester group can be used to enable non-specific crosslinking within the proximity of these lysine residues. Here we develop three such isotopically-coded hetero-bifunctional photo-reactive crosslinkers, bearing azido, diazirine or benzophenone photo-reactive groups (azido-benzoic-acid-succinimide (ABAS)-(12)C6/(13)C6, succinimidyl-diazirine (SDA)-(12)C5/(13)C5, and carboxy-benzophenone-succinimide (CBS)-(12)C6/(13)C6, respectively). These crosslinkers were validated using several model proteins/peptides and were then applied to study the structure of the native α-synuclein protein. In that case the ABAS crosslinker proved to be the most suitable, with 10 crosslinks being found in the native α-synuclein structure. BIOLOGICAL SIGNIFICANCE Structural proteomics can be used for studying protein structures which may be difficult to examine by traditional structural biology methods such as NMR or X-ray crystallography. Crosslinking in particular is used to provide distance constraints for molecular modeling of individual proteins and protein complexes. The shortest distance constraints are most valuable for the modeling process. To be able to provide such short distance constraints, non-specific photo-reactive chemistry can be used for crosslinking reactions. However, detection of such non-specific crosslinks is difficult because the signal from any particular crosslink is low due to the broad reactivity of the crosslinking reagents. To overcome this problem, we have employed isotopic labeling of these crosslinkers. In this paper, we have demonstrated their effectiveness for studying the native α-synuclein protein structure. The non-specific reactivity, in combination with isotopic coding of these crosslinkers, allowed for the formation and detection of short-range crosslinks, targeting a variety of amino acids. These reagents may prove useful for future applications to a variety of protein structural problems. This article is part of a Special Issue entitled: Protein dynamics in health and disease. Guest Editors: Pierre Thibault and Anne-Claude Gingras.
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Affiliation(s)
- Nicholas I Brodie
- University of Victoria - Genome British Columbia Proteomics Centre, University of Victoria, #3101-4464 Markham Street, Vancouver Island Technology Park, Victoria V8Z7X8, Canada
| | - Karl A T Makepeace
- University of Victoria - Genome British Columbia Proteomics Centre, University of Victoria, #3101-4464 Markham Street, Vancouver Island Technology Park, Victoria V8Z7X8, Canada
| | - Evgeniy V Petrotchenko
- University of Victoria - Genome British Columbia Proteomics Centre, University of Victoria, #3101-4464 Markham Street, Vancouver Island Technology Park, Victoria V8Z7X8, Canada
| | - Christoph H Borchers
- University of Victoria - Genome British Columbia Proteomics Centre, University of Victoria, #3101-4464 Markham Street, Vancouver Island Technology Park, Victoria V8Z7X8, Canada; Department of Biochemistry & Microbiology, University of Victoria, Petch Building Room 207, 3800 Finnerty Rd., Victoria, BC V8P 5C2, Canada.
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Smith BR, Santos MB, Marshall MS, Cantuti-Castelvetri L, Lopez-Rosas A, Li G, van Breemen R, Claycomb KI, Gallea JI, Celej SM, Crocker S, Givogri MI, Bongarzone ER. Neuronal inclusions of α-synuclein contribute to the pathogenesis of Krabbe disease. J Pathol 2014; 232:509-21. [PMID: 24415155 PMCID: PMC3977150 DOI: 10.1002/path.4328] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Revised: 11/26/2013] [Accepted: 12/29/2013] [Indexed: 11/11/2022]
Abstract
Demyelination is a major contributor to the general decay of neural functions in children with Krabbe disease. However, recent reports have indicated a significant involvement of neurons and axons in the neuropathology of the disease. In this study, we have investigated the nature of cellular inclusions in the Krabbe brain. Brain samples from the twitcher mouse model for Krabbe disease and from patients affected with the infantile and late-onset forms of the disease were examined for the presence of neuronal inclusions. Our experiments demonstrated the presence of cytoplasmic aggregates of thioflavin-S-reactive material in both human and murine mutant brains. Most of these inclusions were associated with neurons. A few inclusions were detected to be associated with microglia and none were associated with astrocytes or oligodendrocytes. Thioflavin-S-reactive inclusions increased in abundance, paralleling the development of neurological symptoms, and distributed throughout the twitcher brain in areas of major involvement in cognition and motor functions. Electron microscopy confirmed the presence of aggregates of stereotypic β-sheet folded proteinaceous material. Immunochemical analyses identified the presence of aggregated forms of α-synuclein and ubiquitin, proteins involved in the formation of Lewy bodies in Parkinson's disease and other neurodegenerative conditions. In vitro assays demonstrated that psychosine, the neurotoxic sphingolipid accumulated in Krabbe disease, accelerated the fibrillization of α-synuclein. This study demonstrates the occurrence of neuronal deposits of fibrillized proteins including α-synuclein, identifying Krabbe disease as a new α-synucleinopathy.
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Affiliation(s)
- Benjamin R. Smith
- Department of Anatomy and Cell Biology, College of Medicine, University of Illinois, University of Illinois Chicago, Chicago Il 60612
| | - Marta B. Santos
- Department of Anatomy and Cell Biology, College of Medicine, University of Illinois, University of Illinois Chicago, Chicago Il 60612
| | - Michael S. Marshall
- Department of Anatomy and Cell Biology, College of Medicine, University of Illinois, University of Illinois Chicago, Chicago Il 60612
| | - Ludovico Cantuti-Castelvetri
- Department of Anatomy and Cell Biology, College of Medicine, University of Illinois, University of Illinois Chicago, Chicago Il 60612
| | - Aurora Lopez-Rosas
- Department of Anatomy and Cell Biology, College of Medicine, University of Illinois, University of Illinois Chicago, Chicago Il 60612
| | - Guanan Li
- Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois, University of Illinois Chicago, Chicago Il 60612
| | - Richard van Breemen
- Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois, University of Illinois Chicago, Chicago Il 60612
| | - Kumiko I. Claycomb
- Department of Neuroscience, University of Connecticut Health Center, Farmington, CT
| | - Jose I. Gallea
- Departamento de Quimica Biologica, CIQUIBIC, CONICET, Universidad Nacional de Cordoba, Cordoba, Argentina
| | - Soledad M. Celej
- Departamento de Quimica Biologica, CIQUIBIC, CONICET, Universidad Nacional de Cordoba, Cordoba, Argentina
| | - Stephen Crocker
- Department of Neuroscience, University of Connecticut Health Center, Farmington, CT
| | - Maria I. Givogri
- Department of Anatomy and Cell Biology, College of Medicine, University of Illinois, University of Illinois Chicago, Chicago Il 60612
| | - Ernesto R. Bongarzone
- Department of Anatomy and Cell Biology, College of Medicine, University of Illinois, University of Illinois Chicago, Chicago Il 60612
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48
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Ducas VC, Rhoades E. Investigation of intramolecular dynamics and conformations of α-, β- and γ-synuclein. PLoS One 2014; 9:e86983. [PMID: 24489820 PMCID: PMC3904966 DOI: 10.1371/journal.pone.0086983] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2013] [Accepted: 12/18/2013] [Indexed: 01/01/2023] Open
Abstract
The synucleins are a family of natively unstructured proteins consisting of α-, β-, and γ-synuclein which are primarily expressed in neurons. They have been linked to a wide variety of pathologies, including neurological disorders, such as Parkinson's disease (α-synuclein) and dementia with Lewy bodies (α- and β-synuclein), as well as various types of cancers (γ-synuclein). Self-association is a key pathological feature of many of these disorders, with α-synuclein having the highest propensity to form aggregates, while β-synuclein is the least prone. Here, we used a combination of fluorescence correlation spectroscopy and single molecule Förster resonance energy transfer to compare the intrinsic dynamics of different regions of all three synuclein proteins to investigate any correlation with putative functional or dysfunctional interactions. Despite a relatively high degree of sequence homology, we find that individual regions sample a broad range of diffusion coefficients, differing by almost a factor of four. At low pH, a condition that accelerates aggregation of α-synuclein, on average smaller diffusion coefficients are measured, supporting a hypothesis that slower intrachain dynamics may be correlated with self-association. Moreover, there is a surprising inverse correlation between dynamics and bulkiness of the segments. Aside from this observation, we could not discern any clear relationship between the physico-chemical properties of the constructs and their intrinsic dynamics. This work suggests that while protein dynamics may play a role in modulating self-association or interactions with other binding partners, other factors, particularly the local cellular environment, may be more important.
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Affiliation(s)
- Vanessa C Ducas
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, United States of America
| | - Elizabeth Rhoades
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, United States of America ; Department of Physics, Yale University, New Haven, Connecticut, United States of America
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49
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Wright JA, McHugh PC, Pan S, Cunningham A, Brown DR. Counter-regulation of alpha- and beta-synuclein expression at the transcriptional level. Mol Cell Neurosci 2013; 57:33-41. [DOI: 10.1016/j.mcn.2013.09.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Revised: 08/22/2013] [Accepted: 09/20/2013] [Indexed: 12/15/2022] Open
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50
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Visanji NP, Brooks PL, Hazrati LN, Lang AE. The prion hypothesis in Parkinson's disease: Braak to the future. Acta Neuropathol Commun 2013; 1:2. [PMID: 24252164 PMCID: PMC3776210 DOI: 10.1186/2051-5960-1-2] [Citation(s) in RCA: 173] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Accepted: 02/22/2013] [Indexed: 11/17/2022] Open
Abstract
Parkinson’s disease (PD) is a progressive neurodegenerative disorder typified by the presence of intraneuronal inclusions containing aggregated alpha synuclein (αsyn). The progression of parkinsonian pathology and clinical phenotype has been broadly demonstrated to follow a specific pattern, most notably described by Braak and colleagues. In more recent times it has been hypothesized that αsyn itself may be a critical factor in mediating transmission of disease pathology from one brain area to another. Here we investigate the growing body of evidence demonstrating the ability of αsyn to spread transcellularly and induce pathological aggregation affecting neurons by permissive templating and provide a critical analysis of some irregularities in the hypothesis that the progression of PD pathology may be mediated by such a prion-like process. Finally we discuss some key questions that remain unanswered which are vital to determining the potential contribution of a prion-like process to the pathogenesis of PD.
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