1
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Röntgen A, Toprakcioglu Z, Tomkins JE, Vendruscolo M. Modulation of α-synuclein in vitro aggregation kinetics by its alternative splice isoforms. Proc Natl Acad Sci U S A 2024; 121:e2313465121. [PMID: 38324572 PMCID: PMC10873642 DOI: 10.1073/pnas.2313465121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Accepted: 12/20/2023] [Indexed: 02/09/2024] Open
Abstract
The misfolding and aggregation of α-synuclein is linked to a family of neurodegenerative disorders known as synucleinopathies, the most prominent of which is Parkinson's disease (PD). Understanding the aggregation process of α-synuclein from a mechanistic point of view is thus of key importance. SNCA, the gene encoding α-synuclein, comprises six exons and produces various isoforms through alternative splicing. The most abundant isoform is expressed as a 140-amino acid protein (αSyn-140), while three other isoforms, αSyn-126, αSyn-112, and αSyn-98, are generated by skipping exon 3, exon 5, or both exons, respectively. In this study, we performed a detailed biophysical characterization of the aggregation of these four isoforms. We found that αSyn-112 and αSyn-98 exhibit accelerated aggregation kinetics compared to αSyn-140 and form distinct aggregate morphologies, as observed by transmission electron microscopy. Moreover, we observed that the presence of relatively small amounts of αSyn-112 accelerates the aggregation of αSyn-140, significantly reducing the aggregation half-time. These results indicate a potential role of alternative splicing in the pathological aggregation of α-synuclein and provide insights into how this process could be associated with the development of synucleinopathies.
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Affiliation(s)
- Alexander Röntgen
- Centre for Misfolding Diseases, Yusuf HamiedDepartment of Chemistry, University of Cambridge, CambridgeCB2 1EW, United Kingdom
| | - Zenon Toprakcioglu
- Centre for Misfolding Diseases, Yusuf HamiedDepartment of Chemistry, University of Cambridge, CambridgeCB2 1EW, United Kingdom
| | - James E. Tomkins
- Centre for Misfolding Diseases, Yusuf HamiedDepartment of Chemistry, University of Cambridge, CambridgeCB2 1EW, United Kingdom
- Aligning Science Across Parkinson’s Collaborative Research Network, Chevy Chase, MD20815
| | - Michele Vendruscolo
- Centre for Misfolding Diseases, Yusuf HamiedDepartment of Chemistry, University of Cambridge, CambridgeCB2 1EW, United Kingdom
- Aligning Science Across Parkinson’s Collaborative Research Network, Chevy Chase, MD20815
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2
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Harvey J, Pishva E, Chouliaras L, Lunnon K. Elucidating distinct molecular signatures of Lewy body dementias. Neurobiol Dis 2023; 188:106337. [PMID: 37918758 DOI: 10.1016/j.nbd.2023.106337] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Revised: 10/15/2023] [Accepted: 10/27/2023] [Indexed: 11/04/2023] Open
Abstract
Dementia with Lewy bodies and Parkinson's disease dementia are common neurodegenerative diseases that share similar neuropathological profiles and spectra of clinical symptoms but are primarily differentiated by the order in which symptoms manifest. The question of whether a distinct molecular pathological profile could distinguish these disorders is yet to be answered. However, in recent years, studies have begun to investigate genomic, epigenomic, transcriptomic and proteomic differences that may differentiate these disorders, providing novel insights in to disease etiology. In this review, we present an overview of the clinical and pathological hallmarks of Lewy body dementias before summarizing relevant research into genetic, epigenetic, transcriptional and protein signatures in these diseases, with a particular interest in those resolving "omic" level changes. We conclude by suggesting future research directions to address current gaps and questions present within the field.
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Affiliation(s)
- Joshua Harvey
- Department of Clinical and Biomedical Sciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, UK
| | - Ehsan Pishva
- Department of Clinical and Biomedical Sciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, UK; Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience (MHeNS), Maastricht University, Maastricht, the Netherlands
| | - Leonidas Chouliaras
- Department of Psychiatry, School of Clinical Medicine, University of Cambridge, Cambridge, UK; Specialist Dementia and Frailty Service, Essex Partnership University NHS Foundation Trust, Epping, UK
| | - Katie Lunnon
- Department of Clinical and Biomedical Sciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, UK.
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3
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Sastre D, Zafar F, Torres CAM, Piper D, Kirik D, Sanders LH, Qi LS, Schüle B. Inactive S. aureus Cas9 downregulates alpha-synuclein and reduces mtDNA damage and oxidative stress levels in human stem cell model of Parkinson's disease. Sci Rep 2023; 13:17796. [PMID: 37853101 PMCID: PMC10584834 DOI: 10.1038/s41598-023-45078-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 10/16/2023] [Indexed: 10/20/2023] Open
Abstract
Parkinson's disease (PD) is one of the most common neurodegenerative diseases, but no disease modifying therapies have been successful in clinical translation presenting a major unmet medical need. A promising target is alpha-synuclein or its aggregated form, which accumulates in the brain of PD patients as Lewy bodies. While it is not entirely clear which alpha-synuclein protein species is disease relevant, mere overexpression of alpha-synuclein in hereditary forms leads to neurodegeneration. To specifically address gene regulation of alpha-synuclein, we developed a CRISPR interference (CRISPRi) system based on the nuclease dead S. aureus Cas9 (SadCas9) fused with the transcriptional repressor domain Krueppel-associated box to controllably repress alpha-synuclein expression at the transcriptional level. We screened single guide (sg)RNAs across the SNCA promoter and identified several sgRNAs that mediate downregulation of alpha-synuclein at varying levels. CRISPRi downregulation of alpha-synuclein in iPSC-derived neuronal cultures from a patient with an SNCA genomic triplication showed functional recovery by reduction of oxidative stress and mitochondrial DNA damage. Our results are proof-of-concept in vitro for precision medicine by targeting the SNCA gene promoter. The SNCA CRISPRi approach presents a new model to understand safe levels of alpha-synuclein downregulation and a novel therapeutic strategy for PD and related alpha-synucleinopathies.
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Affiliation(s)
- Danuta Sastre
- Department of Pathology, Stanford University School of Medicine, 300 Pasteur Dr., R271/217, Stanford, CA, 94305, USA
| | - Faria Zafar
- Department of Pathology, Stanford University School of Medicine, 300 Pasteur Dr., R271/217, Stanford, CA, 94305, USA
| | - C Alejandra Morato Torres
- Department of Pathology, Stanford University School of Medicine, 300 Pasteur Dr., R271/217, Stanford, CA, 94305, USA
| | - Desiree Piper
- Department of Biological Sciences, San Jose State University, San Jose, CA, 95192, USA
| | - Deniz Kirik
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Laurie H Sanders
- Departments of Neurology and Pathology, Duke Center for Neurodegeneration and Neurotherapeutics, Duke University Medical Center, Durham, NC, 27710, USA
| | - L Stanley Qi
- Department of Bioengineering, Stanford University, Stanford, CA, 94305, USA
| | - Birgitt Schüle
- Department of Pathology, Stanford University School of Medicine, 300 Pasteur Dr., R271/217, Stanford, CA, 94305, USA.
- Biosciences Division, SRI International, Menlo Park, CA, 94025, USA.
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4
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Nikom D, Zheng S. Alternative splicing in neurodegenerative disease and the promise of RNA therapies. Nat Rev Neurosci 2023; 24:457-473. [PMID: 37336982 DOI: 10.1038/s41583-023-00717-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/02/2023] [Indexed: 06/21/2023]
Abstract
Alternative splicing generates a myriad of RNA products and protein isoforms of different functions from a single gene. Dysregulated alternative splicing has emerged as a new mechanism broadly implicated in the pathogenesis of neurodegenerative diseases such as Alzheimer disease, amyotrophic lateral sclerosis, frontotemporal dementia, Parkinson disease and repeat expansion diseases. Understanding the mechanisms and functional outcomes of abnormal splicing in neurological disorders is vital in developing effective therapies to treat mis-splicing pathology. In this Review, we discuss emerging research and evidence of the roles of alternative splicing defects in major neurodegenerative diseases and summarize the latest advances in RNA-based therapeutic strategies to target these disorders.
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Affiliation(s)
- David Nikom
- Neuroscience Graduate Program, University of California, Riverside, Riverside, CA, USA
- Center for RNA Biology and Medicine, University of California, Riverside, Riverside, CA, USA
| | - Sika Zheng
- Neuroscience Graduate Program, University of California, Riverside, Riverside, CA, USA.
- Center for RNA Biology and Medicine, University of California, Riverside, Riverside, CA, USA.
- Division of Biomedical Sciences, University of California, Riverside, Riverside, CA, USA.
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5
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Tassinari V, La Rosa P, Guida E, Colopi A, Caratelli S, De Paolis F, Gallo A, Cenciarelli C, Sconocchia G, Dolci S, Cesarini V. Contribution of A-to-I RNA editing, M6A RNA Methylation, and Alternative Splicing to physiological brain aging and neurodegenerative diseases. Mech Ageing Dev 2023; 212:111807. [PMID: 37023929 DOI: 10.1016/j.mad.2023.111807] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 03/31/2023] [Accepted: 04/03/2023] [Indexed: 04/08/2023]
Abstract
Aging is a physiological and progressive phenomenon in all organisms' life cycle, characterized by the accumulation of degenerative processes triggered by several alterations within molecular pathways. These changes compromise cell fate, resulting in the loss of functions in tissues throughout the body, including the brain. Physiological brain aging has been linked to structural and functional alterations, as well as to an increased risk of neurodegenerative diseases. Post-transcriptional RNA modifications modulate mRNA coding properties, stability, translatability, expanding the coding capacity of the genome, and are involved in all cellular processes. Among mRNA post-transcriptional modifications, the A-to-I RNA editing, m6A RNA Methylation and Alternative Splicing play a critical role in all the phases of a neuronal cell life cycle and alterations in their mechanisms of action significantly contribute to aging and neurodegeneration. Here we review our current understanding of the contribution of A-to-I RNA editing, m6A RNA Methylation, and Alternative Splicing to physiological brain aging process and neurodegenerative diseases.
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Affiliation(s)
- Valentina Tassinari
- Department of Molecular Medicine, Sapienza University of Rome, Rome, Italy; Department of Experimental Medicine, University of Rome Tor Vergata, Rome, Italy.
| | - Piergiorgio La Rosa
- Division of Neuroscience, Department of Psychology, Sapienza University of Rome, Rome, Italy; European Center for Brain Research, IRCCS Fondazione Santa Lucia, Rome, Italy
| | - Eugenia Guida
- Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy
| | - Ambra Colopi
- Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy
| | - Sara Caratelli
- Department of Biomedicine, Institute of Translational Pharmacology (IFT), National Research Council (CNR), Rome, Italy
| | - Francesca De Paolis
- Department of Biomedicine, Institute of Translational Pharmacology (IFT), National Research Council (CNR), Rome, Italy
| | - Angela Gallo
- RNA Editing Lab., Oncohaematology Department, Cellular and Gene Therapy Unit, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Carlo Cenciarelli
- Department of Biomedicine, Institute of Translational Pharmacology (IFT), National Research Council (CNR), Rome, Italy
| | - Giuseppe Sconocchia
- Department of Biomedicine, Institute of Translational Pharmacology (IFT), National Research Council (CNR), Rome, Italy
| | - Susanna Dolci
- Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy
| | - Valeriana Cesarini
- Department of Biomedicine, Institute of Translational Pharmacology (IFT), National Research Council (CNR), Rome, Italy.
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6
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Sastre D, Zafar F, Torres CAM, Piper D, Kirik D, Sanders LH, Qi S, Schüle B. Nuclease-dead S. aureus Cas9 downregulates alpha-synuclein and reduces mtDNA damage and oxidative stress levels in patient-derived stem cell model of Parkinson's disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.24.525105. [PMID: 36747875 PMCID: PMC9900844 DOI: 10.1101/2023.01.24.525105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Parkinson's disease (PD) is one of the most common neurodegenerative diseases, but no disease modifying therapies have been successful in clinical translation presenting a major unmet medical need. A promising target is alpha-synuclein or its aggregated form, which accumulates in the brain of PD patients as Lewy bodies. While it is not entirely clear which alpha-synuclein protein species is disease relevant, mere overexpression of alpha-synuclein in hereditary forms leads to neurodegeneration. To specifically address gene regulation of alpha-synuclein, we developed a CRISPR interference (CRISPRi) system based on the nuclease dead S. aureus Cas9 (SadCas9) fused with the transcriptional repressor domain Krueppel-associated box to controllably repress alpha-synuclein expression at the transcriptional level. We screened single guide (sg)RNAs across the SNCA promoter and identified several sgRNAs that mediate downregulation of alpha-synuclein at varying levels. CRISPRi downregulation of alpha-synuclein in iPSC-derived neuronal cultures from a patient with an SNCA genomic triplication showed functional recovery by reduction of oxidative stress and mitochondrial DNA damage. Our results are proof-of-concept in vitro for precision medicine by targeting the SNCA gene promoter. The SNCA CRISPRi approach presents a new model to understand safe levels of alpha-synuclein downregulation and a novel therapeutic strategy for PD and related alpha-synucleinopathies.
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Affiliation(s)
- Danuta Sastre
- Stanford University School of Medicine, Department of Pathology, Stanford, CA 94305, U.S.A
| | - Faria Zafar
- Stanford University School of Medicine, Department of Pathology, Stanford, CA 94305, U.S.A
| | | | - Desiree Piper
- San Jose State University, Department of Biological Sciences, San Jose, 95192 CA, U.S.A
| | - Deniz Kirik
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Laurie H. Sanders
- Departments of Neurology and Pathology, Duke Center for Neurodegeneration and Neurotherapeutics, Duke University Medical Center, Durham, NC 27710, U.S.A
| | - Stanley Qi
- Stanford University, Department of Bioengineering, Stanford, CA 94305, U.S.A
| | - Birgitt Schüle
- Stanford University School of Medicine, Department of Pathology, Stanford, CA 94305, U.S.A
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7
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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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8
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Chen X, Chen M, Wolynes PG. Exploring the Interplay between Disordered and Ordered Oligomer Channels on the Aggregation Energy Landscapes of α-Synuclein. J Phys Chem B 2022; 126:5250-5261. [PMID: 35815598 DOI: 10.1021/acs.jpcb.2c03676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The abnormal aggregation of α-synulcein is associated with multiple neurodegenerative diseases such as Parkinson's disease. The hydrophobic non-amyloid component (NAC) region of α-synuclein comprises the core of the fibril in vitro and in vivo. In this work, we study the aggregation landscape of the hydrophobic NAC region of α-synuclein using a transferrable coarse-grained force field, the associative memory water-mediated structure, and energy model (AWSEM). Using structural similarity, we can group metastable states on the free energy landscape of aggregation into three types of oligomers: disordered oligomers, prefibrillar oligomers with disordered tips, and ordered prefibrillar oligomers. The prefibrillar oligomers with disordered tips have more in-register parallel β strands than do the fully disordered oligomers but have fewer in-register parallel β strands than the ordered prefibrillar oligomers. Along with the ordered prefibrillar species, the disordered oligomeric states dominate at small oligomer sizes while the prefibrillar species with disordered tips thermodynamically dominate with the growth of oligomers. The topology of the aggregation landscape and observations in simulations suggest there is backtracking between ordered prefibrillar oligomers and other kinds of oligomers as the aggregation proceeds. The significant structural differences between the ordered prefibrillar oligomers and the disordered oligomers support the idea that the growth of these two kinds of oligomers involves kinetically independent parallel pathways. In contrast, the overall structural similarity between the fully ordered prefibrillar oligomers and the prefibrillar oligomers with disordered tips implies that two channels can interconvert on slower time scales. We also evaluate the effects of phosphorylation on the aggregation free energy landscape using statistical mechanical perturbation theory.
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Affiliation(s)
- Xun Chen
- Center for Theoretical Biological Physics, Houston, Texas 77005, United States.,Department of Chemistry, Rice University, Houston, Texas 77005, United States
| | - Mingchen Chen
- Department of Research and Development, neoX Biotech, Beijing 102206, China
| | - Peter G Wolynes
- Center for Theoretical Biological Physics, Houston, Texas 77005, United States.,Department of Chemistry, Rice University, Houston, Texas 77005, United States.,Department of Bioengineering, Rice University, Houston, Texas 77005, United States
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9
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Amyloid Cross-Seeding: Mechanism, Implication, and Inhibition. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27061776. [PMID: 35335141 PMCID: PMC8955620 DOI: 10.3390/molecules27061776] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 03/04/2022] [Accepted: 03/07/2022] [Indexed: 01/21/2023]
Abstract
Most neurodegenerative diseases such as Alzheimer’s disease, type 2 diabetes, Parkinson’s disease, etc. are caused by inclusions and plaques containing misfolded protein aggregates. These protein aggregates are essentially formed by the interactions of either the same (homologous) or different (heterologous) sequences. Several experimental pieces of evidence have revealed the presence of cross-seeding in amyloid proteins, which results in a multicomponent assembly; however, the molecular and structural details remain less explored. Here, we discuss the amyloid proteins and the cross-seeding phenomena in detail. Data suggest that targeting the common epitope of the interacting amyloid proteins may be a better therapeutic option than targeting only one species. We also examine the dual inhibitors that target the amyloid proteins participating in the cross-seeding events. The future scopes and major challenges in understanding the mechanism and developing therapeutics are also considered. Detailed knowledge of the amyloid cross-seeding will stimulate further research in the practical aspects and better designing anti-amyloid therapeutics.
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10
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Medvedev SP, Malankhanova TB, Valetdinova KR, Zakian SM. Creation and Research of Cell Models of Hereditary Neurodegenerative Diseases Using Directed Genome Editing. NEUROCHEM J+ 2021. [DOI: 10.1134/s1819712421040073] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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11
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Serratos IN, Hernández-Pérez E, Campos C, Aschner M, Santamaría A. An Update on the Critical Role of α-Synuclein in Parkinson's Disease and Other Synucleinopathies: from Tissue to Cellular and Molecular Levels. Mol Neurobiol 2021; 59:620-642. [PMID: 34750787 DOI: 10.1007/s12035-021-02596-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 10/08/2021] [Indexed: 12/15/2022]
Abstract
The aggregation of alpha-synuclein (α-Syn) plays a critical role in the development of Parkinson's disease (PD) and other synucleinopathies. α-Syn, which is encoded by the SNCA gene, is a lysine-rich soluble amphipathic protein normally expressed in neurons. Located in the cytosolic domain, this protein has the ability to remodel itself in plasma membranes, where it assumes an alpha-helix conformation. However, the protein can also adopt another conformation rich in cross-beta sheets, undergoing mutations and post-translational modifications, then leading the protein to an unusual aggregation in the form of Lewy bodies (LB), which are cytoplasmic inclusions constituted predominantly by α-Syn. Pathogenic mechanisms affecting the structural and functional stability of α-Syn - such as endoplasmic reticulum stress, Golgi complex fragmentation, disfunctional protein degradation systems, aberrant interactions with mitochondrial membranes and nuclear DNA, altered cytoskeleton dynamics, disrupted neuronal plasmatic membrane, dysfunctional vesicular transport, and formation of extracellular toxic aggregates - contribute all to the pathogenic progression of PD and synucleinopathies. In this review, we describe the collective knowledge on this topic and provide an update on the critical role of α-Syn aggregates, both at the cellular and molecular levels, in the deregulation of organelles affecting the cellular homeostasis and leading to neuronal cell death in PD and other synucleinopathies.
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Affiliation(s)
- Iris N Serratos
- Departamento de Química, Universidad Autónoma Metropolitana-Iztapalapa, 09340, Mexico City, Mexico
| | - Elizabeth Hernández-Pérez
- Departamento de Ciencias de La Salud, Universidad Autónoma Metropolitana-Iztapalapa, 09340, Mexico City, Mexico
| | - Carolina Campos
- Departamento de Ciencias de La Salud, Universidad Autónoma Metropolitana-Iztapalapa, 09340, Mexico City, Mexico.
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY, 10461, USA
| | - Abel Santamaría
- Laboratorio de Aminoácidos Excitadores/Laboratorio de Neurofarmacología Molecular y Nanotecnología, Instituto Nacional de Neurología y Neurocirugía, SSA, 14269, Mexico City, Mexico.
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12
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Scheibe C, Karreman C, Schildknecht S, Leist M, Hauser K. Synuclein Family Members Prevent Membrane Damage by Counteracting α-Synuclein Aggregation. Biomolecules 2021; 11:biom11081067. [PMID: 34439733 DOI: 10.3390/biom11081067] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 07/09/2021] [Accepted: 07/15/2021] [Indexed: 01/09/2023] Open
Abstract
The 140 amino acid protein α-synuclein (αS) is an intrinsically disordered protein (IDP) with various roles and locations in healthy neurons that plays a key role in Parkinson's disease (PD). Contact with biomembranes can lead to α-helical conformations, but can also act as s seeding event for aggregation and a predominant β-sheet conformation. In PD patients, αS is found to aggregate in various fibrillary structures, and the shift in aggregation and localization is associated with disease progression. Besides full-length αS, several related polypeptides are present in neurons. The role of many αS-related proteins in the aggregation of αS itself is not fully understood Two of these potential aggregation modifiers are the αS splicing variant αS Δexon3 (Δ3) and the paralog β-synuclein (βS). Here, polarized ATR-FTIR spectroscopy was used to study the membrane interaction of these proteins individually and in various combinations. The method allowed a continuous monitoring of both the lipid structure of biomimetic membranes and the aggregation state of αS and related proteins. The use of polarized light also revealed the orientation of secondary structure elements. While αS led to a destruction of the lipid membrane upon membrane-catalyzed aggregation, βS and Δ3 aggregated significantly less, and they did not harm the membrane. Moreover, the latter proteins reduced the membrane damage triggered by αS. There were no major differences in the membrane interaction for the different synuclein variants. In combination, these observations suggest that the formation of particular protein aggregates is the major driving force for αS-driven membrane damage. The misbalance of αS, βS, and Δ3 might therefore play a crucial role in neurodegenerative disease.
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Affiliation(s)
- Christian Scheibe
- Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
| | | | - Stefan Schildknecht
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany
- Department of Life Sciences, Albstadt-Sigmaringen University of Applied Sciences, 72488 Sigmaringen, Germany
| | - Marcel Leist
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany
| | - Karin Hauser
- Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
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13
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Larsen K, Bæk R, Sahin C, Kjær L, Christiansen G, Nielsen J, Farajzadeh L, Otzen DE. Molecular characteristics of porcine alpha-synuclein splicing variants. Biochimie 2020; 180:121-133. [PMID: 33152422 DOI: 10.1016/j.biochi.2020.10.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 10/05/2020] [Accepted: 10/30/2020] [Indexed: 12/15/2022]
Abstract
Alpha-synuclein (α-syn) is a 140 amino acid, intrinsically disordered protein with a potential role in neurotransmitter vesicle release. The protein is natively unfolded under physiological conditions, and is expressed predominantly in neural tissue. α-syn is associated with neuropathological conditions in Parkinson's disease, where the protein misfolds into oligomers and fibrils resulting in aggregates in Lewy bodies. Here we report the molecular cloning of SNCA cDNA encoding porcine α-syn and transcript variants hereof. Six transcripts coding for porcine α-syn are presented in the report, of which three result from exon skipping, generating in-frame splicing of coding exons 3 and 5. The splicing pattern of these alternative spliced variants is conserved between human and pig. All the observed in-frame deletions yield significantly shorter α-syn proteins compared with the 140 amino acid full-length protein. Expression analysis performed by real-time quantitative RT-PCR revealed a differential expression of the six transcript splicing variants in different pig organs and tissues. Common for all splicing variants, a very high transcript expression was detected in brain tissues and in spinal cord and very low or no expression outside the central nervous system. The porcine α-syn protein demonstrated markedly different biophysical characteristics compared with its human counterpart. No fibrillation of porcine α-syn was observed with the pig wild-type α-syn and A30P α-syn, and both variants show significantly reduced ability to bind to lipid vesicles. Overexpression of mutated porcine α-syn might recapitulate the human PD pathogenesis and lead to the identification of genetic modifiers of the disease.
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Affiliation(s)
- Knud Larsen
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Allé 3, DK-8000, Aarhus C, Denmark.
| | - Rikke Bæk
- Department of Clinical Immunology, Aalborg University Hospital, Urbansgade 32, DK-9000, Aalborg, Denmark.
| | - Cagla Sahin
- Interdisciplinary Nanoscience Center and Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 14, DK-8000, Aarhus C, Denmark.
| | - Lars Kjær
- Interdisciplinary Nanoscience Center and Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 14, DK-8000, Aarhus C, Denmark.
| | - Gunna Christiansen
- Department of Biomedicine, Aarhus University, Wilhelm Meyers Allé 4, DK-8000, Aarhus C, Denmark.
| | - Janni Nielsen
- Interdisciplinary Nanoscience Center and Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 14, DK-8000, Aarhus C, Denmark.
| | - Leila Farajzadeh
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Allé 3, DK-8000, Aarhus C, Denmark.
| | - Daniel E Otzen
- Interdisciplinary Nanoscience Center and Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 14, DK-8000, Aarhus C, Denmark.
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14
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Sorrentino ZA, Giasson BI. The emerging role of α-synuclein truncation in aggregation and disease. J Biol Chem 2020; 295:10224-10244. [PMID: 32424039 DOI: 10.1074/jbc.rev120.011743] [Citation(s) in RCA: 91] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 05/13/2020] [Indexed: 12/21/2022] Open
Abstract
α-Synuclein (αsyn) is an abundant brain neuronal protein that can misfold and polymerize to form toxic fibrils coalescing into pathologic inclusions in neurodegenerative diseases, including Parkinson's disease, Lewy body dementia, and multiple system atrophy. These fibrils may induce further αsyn misfolding and propagation of pathologic fibrils in a prion-like process. It is unclear why αsyn initially misfolds, but a growing body of literature suggests a critical role of partial proteolytic processing resulting in various truncations of the highly charged and flexible carboxyl-terminal region. This review aims to 1) summarize recent evidence that disease-specific proteolytic truncations of αsyn occur in Parkinson's disease, Lewy body dementia, and multiple system atrophy and animal disease models; 2) provide mechanistic insights on how truncation of the amino and carboxyl regions of αsyn may modulate the propensity of αsyn to pathologically misfold; 3) compare experiments evaluating the prion-like properties of truncated forms of αsyn in various models with implications for disease progression; 4) assess uniquely toxic properties imparted to αsyn upon truncation; and 5) discuss pathways through which truncated αsyn forms and therapies targeted to interrupt them. Cumulatively, it is evident that truncation of αsyn, particularly carboxyl truncation that can be augmented by dysfunctional proteostasis, dramatically potentiates the propensity of αsyn to pathologically misfold into uniquely toxic fibrils with modulated prion-like seeding activity. Therapeutic strategies and experimental paradigms should operate under the assumption that truncation of αsyn is likely occurring in both initial and progressive disease stages, and preventing truncation may be an effective preventative strategy against pathologic inclusion formation.
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Affiliation(s)
- Zachary A Sorrentino
- Department of Neuroscience, College of Medicine, University of Florida, Gainesville, Florida, USA.,Center for Translational Research in Neurodegenerative Disease, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Benoit I Giasson
- Department of Neuroscience, College of Medicine, University of Florida, Gainesville, Florida, USA .,Center for Translational Research in Neurodegenerative Disease, College of Medicine, University of Florida, Gainesville, Florida, USA.,McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida, USA
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15
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Chaudhuri P, Prajapati KP, Anand BG, Dubey K, Kar K. Amyloid cross-seeding raises new dimensions to understanding of amyloidogenesis mechanism. Ageing Res Rev 2019; 56:100937. [PMID: 31430565 DOI: 10.1016/j.arr.2019.100937] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 06/21/2019] [Accepted: 07/23/2019] [Indexed: 12/12/2022]
Abstract
Hallmarks of most of the amyloid pathologies are surprisingly found to be heterocomponent entities such as inclusions and plaques which contain diverse essential proteins and metabolites. Experimental studies have already revealed the occurrence of coaggregation and cross-seeding during amyloid formation of several proteins and peptides, yielding multicomponent assemblies of amyloid nature. Further, research reports on the co-occurrence of more than one type of amyloid-linked pathologies in the same individual suggest the possible cross-talk among the disease related amyloidogenic protein species during their amyloid growth. In this review paper, we have tried to gain more insight into the process of coaggregation and cross-seeding during amyloid aggregation of proteins, particularly focusing on their relevance to the pathogenesis of the protein misfolding diseases. Revelation of amyloid cross-seeding and coaggregation seems to open new dimensions in our mechanistic understanding of amyloidogenesis and such knowledge may possibly inspire better designing of anti-amyloid therapeutics.
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16
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Du T, Wu Z, Luo H, Lu S, Ma K. Injection of α-syn-98 Aggregates Into the Brain Triggers α-Synuclein Pathology and an Inflammatory Response. Front Mol Neurosci 2019; 12:189. [PMID: 31447645 PMCID: PMC6691047 DOI: 10.3389/fnmol.2019.00189] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 07/22/2019] [Indexed: 11/24/2022] Open
Abstract
Pathological aggregation of α-synuclein (α-syn) is a major component of Lewy bodies (LB), which play a central role in pathogenesis of Parkinson’s disease (PD). Differential expression of α-syn isoforms has been shown in PD. Isoform α-syn-98 is generated by excision of exon-3 and exon-5 of the α-syn gene. In contrast to the canonical full-length α-syn isoform (α-syn140), little is known about the function of the α-syn-98 isoform. In the present study, to identify the potential role of α-syn-98 protein in PD, we examined the effects of exogenous recombinant insoluble α-syn-98 aggregates on α-syn pathology and inflammatory responses in the midbrain. After injection of α-syn-98 aggregates into the substantia nigra (SN), mice exhibited motor dysfunction accompanied by nigral dopaminergic neuron loss. In addition, α-syn-98 aggregates injection resulted in a significant increase in phosphorylation of endogenous α-syn. Accumulations of α-syn were co-localized with p62 and ubiquitin, which suggests α-syn-98 aggregates-induced pathology exhibits properties similar to human LB. Many glial cells were activated after α-syn-98 aggregates injection. In addition, expression of NF-κB, interleukin 6 (IL6), and tumor necrosis factor-α (TNF-α) and levels of oxidative stress increased after α-syn-98 aggregates injection. Our results suggest that α-syn-98 may play a crucial role in the pathogenesis of PD.
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Affiliation(s)
- Tingfu Du
- Center for Drug Safety Evaluation and Research, Institute of Medical Biology, Chinese Academy of Medical Sciences, Kunming, China.,Medical Primate Research Center & Neuroscience Center, Chinese Academy of Medical Sciences, Beijing, China.,Yunnan Key Laboratory of Vaccine Research Development on Severe Infectious Diseases, Kunming, China
| | - Zhengcun Wu
- Center for Drug Safety Evaluation and Research, Institute of Medical Biology, Chinese Academy of Medical Sciences, Kunming, China.,Yunnan Key Laboratory of Vaccine Research Development on Severe Infectious Diseases, Kunming, China
| | - Haiyu Luo
- Center for Drug Safety Evaluation and Research, Institute of Medical Biology, Chinese Academy of Medical Sciences, Kunming, China.,Yunnan Key Laboratory of Vaccine Research Development on Severe Infectious Diseases, Kunming, China
| | - Shuaiyao Lu
- Center for Drug Safety Evaluation and Research, Institute of Medical Biology, Chinese Academy of Medical Sciences, Kunming, China.,Yunnan Key Laboratory of Vaccine Research Development on Severe Infectious Diseases, Kunming, China
| | - Kaili Ma
- Center for Drug Safety Evaluation and Research, Institute of Medical Biology, Chinese Academy of Medical Sciences, Kunming, China.,Medical Primate Research Center & Neuroscience Center, Chinese Academy of Medical Sciences, Beijing, China.,Yunnan Key Laboratory of Vaccine Research Development on Severe Infectious Diseases, Kunming, China
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17
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Riederer P, Berg D, Casadei N, Cheng F, Classen J, Dresel C, Jost W, Krüger R, Müller T, Reichmann H, Rieß O, Storch A, Strobel S, van Eimeren T, Völker HU, Winkler J, Winklhofer KF, Wüllner U, Zunke F, Monoranu CM. α-Synuclein in Parkinson's disease: causal or bystander? J Neural Transm (Vienna) 2019; 126:815-840. [PMID: 31240402 DOI: 10.1007/s00702-019-02025-9] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 05/29/2019] [Indexed: 12/13/2022]
Abstract
Parkinson's disease (PD) comprises a spectrum of disorders with differing subtypes, the vast majority of which share Lewy bodies (LB) as a characteristic pathological hallmark. The process(es) underlying LB generation and its causal trigger molecules are not yet fully understood. α-Synuclein (α-syn) is a major component of LB and SNCA gene missense mutations or duplications/triplications are causal for rare hereditary forms of PD. As typical sporadic PD is associated with LB pathology, a factor of major importance is the study of the α-syn protein and its pathology. α-Syn pathology is, however, also evident in multiple system atrophy (MSA) and Lewy body disease (LBD), making it non-specific for PD. In addition, there is an overlap of these α-synucleinopathies with other protein-misfolding diseases. It has been proven that α-syn, phosphorylated tau protein (pτ), amyloid beta (Aβ) and other proteins show synergistic effects in the underlying pathogenic mechanisms. Multiple cell death mechanisms can induce pathological protein-cascades, but this can also be a reverse process. This holds true for the early phases of the disease process and especially for the progression of PD. In conclusion, while rare SNCA gene mutations are causal for a minority of familial PD patients, in sporadic PD (where common SNCA polymorphisms are the most consistent genetic risk factor across populations worldwide, accounting for 95% of PD patients) α-syn pathology is an important feature. Conversely, with regard to the etiopathogenesis of α-synucleinopathies PD, MSA and LBD, α-syn is rather a bystander contributing to multiple neurodegenerative processes, which overlap in their composition and individual strength. Therapeutic developments aiming to impact on α-syn pathology should take this fact into consideration.
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Affiliation(s)
- Peter Riederer
- Clinic and Policlinic for Psychiatry, Psychosomatics and Psychotherapy, University Hospital Würzburg, University of Würzburg, Margarete-Höppel-Platz 1, 97080, Würzburg, Germany. .,Department of Psychiatry, University of South Denmark, Odense, Denmark.
| | - Daniela Berg
- Department of Neurology, UKHS, Christian-Albrechts-Universität, Campus Kiel, Kiel, Germany
| | - Nicolas Casadei
- NGS Competence Center Tübingen, Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Fubo Cheng
- NGS Competence Center Tübingen, Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Joseph Classen
- Department of Neurology, University Hospital Leipzig, Leipzig, Germany
| | - Christian Dresel
- Department of Neurology, Center for Movement Disorders, Neuroimaging Center Mainz, Clinical Neurophysiology, Forschungszentrum Translationale Neurowissenschaften (FTN), Rhein-Main-Neuronetz, Mainz, Germany
| | | | - Rejko Krüger
- Clinical and Experimental Neuroscience, LCSB (Luxembourg Centre for Systems, Biomedicine), University of Luxembourg, Esch-sur-Alzette and Centre Hospitalier de Luxembourg (CHL), Luxembourg, Luxembourg.,National Center for Excellence in Research, Parkinson's disease (NCER-PD), Parkinson Research Clinic, Centre Hospitalier de Luxembourg, Luxembourg, Luxembourg
| | - Thomas Müller
- Department of Neurology, Alexianer St. Joseph Berlin-Weißensee, Berlin, Germany
| | - Heinz Reichmann
- Department of Neurology, University of Dresden, Dresden, Germany
| | - Olaf Rieß
- Institute of Medical Genetics and Applied Genomics, Tübingen, Germany
| | - Alexander Storch
- Department of Neurology, University of Rostock, Rostock, Germany.,German Centre for Neurodegenerative Diseases (DZNE) Rostock/Greifswald, Rostock, Germany
| | - Sabrina Strobel
- Department of Neuropathology, Institute of Pathology, University of Würzburg, Würzburg, Germany
| | - Thilo van Eimeren
- Department of Neurology, University Hospital of Cologne, Cologne, Germany
| | | | - Jürgen Winkler
- Department Kopfkliniken, Molekulare Neurologie, Universitätsklinikum Erlangen, Erlangen, Germany
| | - Konstanze F Winklhofer
- Institute of Biochemistry and Pathobiochemistry, Ruhr-Universität Bochum, Bochum, Germany
| | - Ullrich Wüllner
- Department of Neurology, University of Bonn, German Center for Neurodegenerative Diseases (DZNE Bonn), Bonn, Germany
| | - Friederike Zunke
- Department of Biochemistry, Medical Faculty, University of Kiel, Kiel, Germany
| | - Camelia-Maria Monoranu
- Department of Neuropathology, Institute of Pathology, University of Würzburg, Würzburg, Germany
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18
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Vinnakota RL, Yedlapudi D, Manda KM, Bhamidipati K, Bommakanti KT, RangaLakshmi GS, Kalivendi SV. Identification of an Alternatively Spliced α-Synuclein Isoform That Generates a 41-Amino Acid N-Terminal Truncated Peptide, 41-syn: Role in Dopamine Homeostasis. ACS Chem Neurosci 2018; 9:2948-2958. [PMID: 29996045 DOI: 10.1021/acschemneuro.8b00140] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The presynaptic protein, α-synuclein (α-syn), has been shown to play a crucial role in multiple neurodegenerative diseases, such as Parkinson's disease (PD), Alzheimer's disease (AD), and dementia with Lewy bodies (DLB). The three major domains of α-syn protein were shown to govern its membrane interaction, protein fibrillation, and chaperone activity. So far, four different alternatively spliced isoforms of α-syn, which lack either exon 3 (syn-126) or exon 5 (syn-112) or both (syn-98) resulting in altered function of the proteins, have been identified. In the present study, we have identified the smallest isoform of α-syn due to the skipping of exons 3 and 4 generating a 238 bp transcript. Due to the presence of a premature stop codon, the 238 bp transcript generated a 41 aa N-terminal peptide instead of the 78 aa protein, which is secreted into the extracellular medium when overexpressed in cells. The presence of 41-syn was initially noticed in the substantia nigra of PD autopsy tissues, as well as in cells undergoing oxidative stress. In vitro studies inferred that 41-syn neither aggregates nor alters the aggregation propensity of either WT or 112-syn. Overexpression of 41-syn or treatment of cells with 41-syn peptide did not affect cell viability. However, PC-12 cells treated with 41-syn exhibited a time and dose dependent enhancement in the cellular uptake of dopamine. Based on the physiological role of the N-terminal region of α-syn in modulating membrane trafficking events, we believe that the identification of 41-syn may provide novel impetus in unraveling the physiological basis of alternative splicing events in governing PD pathophysiology.
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Affiliation(s)
| | | | | | | | | | - G Sree RangaLakshmi
- Department of Neurology, Osmania General Hospital, Afzal Gunj, Hyderabad, 500012 TS, India
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19
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Wu ZC, Gao JH, Du TF, Tang DH, Chen NH, Yuan YH, Ma KL. Alpha-synuclein is highly prone to distribution in the hippocampus and midbrain in tree shrews, and its fibrils seed Lewy body-like pathology in primary neurons. Exp Gerontol 2018; 116:37-45. [PMID: 30553024 DOI: 10.1016/j.exger.2018.12.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Revised: 12/09/2018] [Accepted: 12/10/2018] [Indexed: 11/30/2022]
Abstract
The Chinese tree shrew (TS) has many unique advantages that make it suitable for use as an experimental animal model for human disease including moderate body size, low cost of feeding, short reproductive cycle and lifespan, and close phylogenetic relationship to primates. Our previous studies have shown that TS treated with the mitochondrial inhibitor MPTP displayed classic Parkinsonian symptoms. Additionally, the structure of TS alpha-synuclein (α-syn) is highly homologous to that found in humans. Previous studies have concluded that misfolded, fibrillar α-syn is a hallmark of α-synucleinopathies. In this study, we examined the distribution and expression levels of α-syn in different TS brain regions. We also obtained recombinant TS α-syn protein to study its aggregation and cytotoxic properties in primary neurons. Our results showed that α-syn was expressed in numerous different brain regions in TS but was most abundant in the hippocampus and midbrain. The recombinant α-syn of TS displayed straight fibrils when incubated for 72 h in vitro, which is very similar to human α-syn. When exposed to primary neurons, the TS and human α-syn fibrils led to cytotoxicity and Lewy-like pathology. Our findings indicated that TS could be a potential animal model to study the pathology of α-synucleinopathies.
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Affiliation(s)
- Zheng-Cun Wu
- Institute of Medical Biology, Chinese Academy of Medical Sciences, Kunming 650118, China; Medical Primate Research Center & Neuroscience Center, Chinese Academy of Medical Sciences, Beijing 100005, China; Yunnan Key Laboratory of Vaccine Research Development on Severe Infectious Diseases, Kunming 650118, China
| | - Jia-Hong Gao
- Institute of Medical Biology, Chinese Academy of Medical Sciences, Kunming 650118, China; Medical Primate Research Center & Neuroscience Center, Chinese Academy of Medical Sciences, Beijing 100005, China; Yunnan Key Laboratory of Vaccine Research Development on Severe Infectious Diseases, Kunming 650118, China
| | - Ting-Fu Du
- Institute of Medical Biology, Chinese Academy of Medical Sciences, Kunming 650118, China; Medical Primate Research Center & Neuroscience Center, Chinese Academy of Medical Sciences, Beijing 100005, China; Yunnan Key Laboratory of Vaccine Research Development on Severe Infectious Diseases, Kunming 650118, China
| | - Dong-Hong Tang
- Institute of Medical Biology, Chinese Academy of Medical Sciences, Kunming 650118, China; Yunnan Key Laboratory of Vaccine Research Development on Severe Infectious Diseases, Kunming 650118, China
| | - Nai-Hong Chen
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Department of Pharmacology, Institute of Materia Medic, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Yu-He Yuan
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Department of Pharmacology, Institute of Materia Medic, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Kai-Li Ma
- Institute of Medical Biology, Chinese Academy of Medical Sciences, Kunming 650118, China; Medical Primate Research Center & Neuroscience Center, Chinese Academy of Medical Sciences, Beijing 100005, China; Yunnan Key Laboratory of Vaccine Research Development on Severe Infectious Diseases, Kunming 650118, China.
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20
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Barrie ES, Lee S, Frater JT, Kataki M, Scharre DW, Sadee W. Alpha-synuclein mRNA isoform formation and translation affected by polymorphism in the human SNCA 3'UTR. Mol Genet Genomic Med 2018; 6:565-574. [PMID: 29730891 PMCID: PMC6081226 DOI: 10.1002/mgg3.407] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 04/02/2018] [Accepted: 04/05/2018] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND Multiple variants in SNCA, encoding alpha-synuclein, a main component of Lewy bodies, are implicated in Parkinson's disease. METHODS We searched for cis-acting SNCA variants using allelic mRNA ratios in human brain tissues. In a SNCA 3'UTR (2,520 bp) luciferase reporter gene assay, translation in SH-SY5Y cells in the presence of the rs17016074 G/A alleles was measured. To assess clinical impact, we queried neurocognitive genome-wide association studies. RESULTS Allelic ratios deviated up to twofold, measured at a marker SNP in the middle of a long 3' untranslated region (3'UTR), but not at a marker at its start, suggesting regulation of 3'UTR processing. 3'UTR SNP rs17016074 G/A, minor allele frequency (MAF) <1% in Caucasians, 13% in Africans, strongly associates with large allelic mRNA expression imbalance (AEI), resulting in reduced expression of long 3'UTR isoforms. A second 3'UTR SNP (rs356165) associates with moderate AEI and enhances SNCA mRNA expression. The rs17016074 A allele reduces overall 3'UTR expression in luciferase reporter gene assays but supports more efficient translation, resolving previous contradictory results. We failed to detect significant genome-wide associations for rs17016074, possibly a result of low MAF in Caucasians or its absence from most genotyping panels. In the "Genome Wide Association Study of Yoruba in Nigeria," rs356165 was associated with reduced memory performance. CONCLUSIONS Here, we identify two cis-acting regulatory variants affecting SNCA mRNA expression, measured by allelic ratios in the 3'UTR. The rs17016074 minor A allele is associated with higher expression of luciferase protein activity. Resolving the genetic influence of SNCA polymorphisms requires study of the interactions between multiple regulatory variants with distinct frequencies among populations.
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Affiliation(s)
- Elizabeth S. Barrie
- Institute for Genomic MedicineNationwide Children's HospitalColumbusOhio
- Center for PharmacogenomicsDepartment of Cancer Biology and GeneticsCollege of MedicineThe Ohio State UniversityColumbusOhio
| | - Sung‐Ha Lee
- Center for PharmacogenomicsDepartment of Cancer Biology and GeneticsCollege of MedicineThe Ohio State UniversityColumbusOhio
| | - John T. Frater
- Center for PharmacogenomicsDepartment of Cancer Biology and GeneticsCollege of MedicineThe Ohio State UniversityColumbusOhio
| | - Maria Kataki
- Division of Cognitive NeurologyDepartment of NeurologyThe Ohio State University Wexner Medical CenterColumbusOhio
| | - Douglas W. Scharre
- Division of Cognitive NeurologyDepartment of NeurologyThe Ohio State University Wexner Medical CenterColumbusOhio
| | - Wolfgang Sadee
- Center for PharmacogenomicsDepartment of Cancer Biology and GeneticsCollege of MedicineThe Ohio State UniversityColumbusOhio
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21
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Gámez-Valero A, Beyer K. Alternative Splicing of Alpha- and Beta-Synuclein Genes Plays Differential Roles in Synucleinopathies. Genes (Basel) 2018; 9:genes9020063. [PMID: 29370097 PMCID: PMC5852559 DOI: 10.3390/genes9020063] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 01/15/2018] [Accepted: 01/17/2018] [Indexed: 11/16/2022] Open
Abstract
The synuclein family is composed of three members, two of which, α- and β-synuclein, play a major role in the development of synucleinopathies, including Parkinson’s disease (PD) as most important movement disorder, dementia with Lewy bodies (DLB) as the second most frequent cause of dementia after Alzheimer’s disease and multiple system atrophy. Whereas abnormal oligomerization and fibrillation of α-synuclein are now well recognized as initial steps in the development of synucleinopathies, β-synuclein is thought to be a natural α-synuclein anti-aggregant. α-synuclein is encoded by the SNCA gene, and β-synuclein by SNCB. Both genes are homologous and undergo complex splicing events. On one hand, in-frame splicing of coding exons gives rise to at least three shorter transcripts, and the functional properties of the corresponding protein isoforms are different. Another type of alternative splicing is the alternative inclusion of at least four initial exons in the case of SNCA, and two in the case of SNCB. Finally, different lengths of 3’ untranslated regions have been also reported for both genes. SNCB only expresses in the brain, but some of the numerous SNCA transcripts are also brain-specific. With the present article, we aim to provide a systematic review of disease related changes in the differential expression of the various SNCA and SNCB transcript variants in brain, blood, and non-neuronal tissue of synucleinopathies, but especially PD and DLB as major neurodegenerative disorders.
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Affiliation(s)
- Ana Gámez-Valero
- Department of Pathology, Germans Trias i Pujol Research Institute, Badalona, 08916 Barcelona, Spain.
| | - Katrin Beyer
- Department of Pathology, Germans Trias i Pujol Research Institute, Badalona, 08916 Barcelona, Spain.
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22
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Homma T, Mochizuki Y, Komori T, Isozaki E. Frequent globular neuronal cytoplasmic inclusions in the medial temporal region as a possible characteristic feature in multiple system atrophy with dementia. Neuropathology 2016; 36:421-431. [DOI: 10.1111/neup.12289] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Revised: 01/03/2016] [Accepted: 01/03/2016] [Indexed: 11/29/2022]
Affiliation(s)
- Taku Homma
- Department of Pathology; Tokyo Metropolitan Neurological Hospital; Fuchu Tokyo Japan
- Department of Pathology; Nihon University School of Medicine; Itabashi Tokyo Japan
| | - Yoko Mochizuki
- Department of Pathology; Tokyo Metropolitan Neurological Hospital; Fuchu Tokyo Japan
- Department of Neurology; Tokyo Metropolitan Kita Medical and Rehabilitation Centre for the Disabled; Kita-ku Tokyo Japan
| | - Takashi Komori
- Department of Pathology; Tokyo Metropolitan Neurological Hospital; Fuchu Tokyo Japan
| | - Eiji Isozaki
- Department of Neurology; Tokyo Metropolitan Neurological Hospital, Tokyo Metropolitan Neurological Hospital; Fuchu-shi Tokyo Japan
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23
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Brudek T, Winge K, Rasmussen NB, Bahl JMC, Tanassi J, Agander TK, Hyde TM, Pakkenberg B. Altered α-synuclein, parkin, and synphilin isoform levels in multiple system atrophy brains. J Neurochem 2015; 136:172-85. [DOI: 10.1111/jnc.13392] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 09/29/2015] [Indexed: 01/16/2023]
Affiliation(s)
- Tomasz Brudek
- Research Laboratory for Stereology and Neuroscience; Bispebjerg-Frederiksberg Hospital; University Hospital of Copenhagen; Copenhagen NV Denmark
- Bispebjerg Movement Disorders Biobank; Bispebjerg-Frederiksberg Hospital; University Hospital of Copenhagen; Copenhagen N Denmark
| | - Kristian Winge
- Department of Neurology; Bispebjerg-Frederiksberg Hospital; University Hospital of Copenhagen; Copenhagen NV Denmark
- Bispebjerg Movement Disorders Biobank; Bispebjerg-Frederiksberg Hospital; University Hospital of Copenhagen; Copenhagen N Denmark
| | - Nadja Bredo Rasmussen
- Research Laboratory for Stereology and Neuroscience; Bispebjerg-Frederiksberg Hospital; University Hospital of Copenhagen; Copenhagen NV Denmark
| | | | - Julia Tanassi
- Department of Autoimmunology and Biomarkers; Statens Serum Institut; Copenhagen S Denmark
| | | | - Thomas M. Hyde
- Lieber Institute for Brain Development; Johns Hopkins Medical Campus; Baltimore Maryland USA
- Department of Psychiatry and Behavioral Sciences; Johns Hopkins University School of Medicine; Baltimore Maryland USA
- Department of Neurology; Johns Hopkins University School of Medicine; Baltimore Maryland USA
| | - Bente Pakkenberg
- Research Laboratory for Stereology and Neuroscience; Bispebjerg-Frederiksberg Hospital; University Hospital of Copenhagen; Copenhagen NV Denmark
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24
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Janeczek P, Brooker C, Dodd PR, Lewohl JM. Differential expression of α-synuclein splice variants in the brain of alcohol misusers: Influence of genotype. Drug Alcohol Depend 2015; 155:284-92. [PMID: 26297298 DOI: 10.1016/j.drugalcdep.2015.05.045] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Revised: 05/28/2015] [Accepted: 05/28/2015] [Indexed: 12/31/2022]
Abstract
BACKGROUND Chronic alcohol misuse causes damage in the central nervous system that may lead to tolerance, craving and dependence. These behavioural changes are likely the result of cellular adaptations that include changes in gene expression. α-Synuclein is involved in the dopaminergic reward pathway, where it regulates dopamine synthesis and release. Previous studies have found that the gene for α-synuclein, SNCA, is differentially expressed in alcohol misusers. METHODS The present study measured the expression of three α-synuclein variants, SNCA-140, SNCA-112, and SNCA-115 in the prefrontal cortex of controls and alcohol misusers with and without cirrhosis of the liver. In addition, eight SNPs located in the 5'- and 3'-UTRs were genotyped in a Caucasian population of 125 controls and 115 alcohol misusers. RESULTS The expression of SNCA-140 and SNCA-112 was significantly lower in alcohol misusers with cirrhosis than in controls. However, SNCA-115 expression was significantly greater in alcohol misusers with cirrhosis than in controls. Allele and genotype frequencies differed significantly between alcohol misusers and controls for three SNPs, rs356221, rs356219 and rs2736995. Two SNPs, rs356221 and rs356219, were in high linkage disequilibrium. There was no increased risk of alcoholism associated with specific genotypes or haplotypes. Our results suggest that the rs356219/356221 G-A haplotype may decrease the chance of having an alcohol misuse phenotype. CONCLUSION These findings suggest that alcohol misuse may alter the expression of the individual α-synuclein splice variants differently in human brain. There was no evidence of an effect of sequence variation on the expression of α-synuclein splice variants in this population.
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Affiliation(s)
- Paulina Janeczek
- Menzies Health Institute Queensland, School of Medical Sciences, Griffith University, Gold Coast Campus, Southport, Australia
| | - Corinne Brooker
- Menzies Health Institute Queensland, School of Medical Sciences, Griffith University, Gold Coast Campus, Southport, Australia
| | - Peter R Dodd
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Australia
| | - Joanne M Lewohl
- Menzies Health Institute Queensland, School of Medical Sciences, Griffith University, Gold Coast Campus, Southport, Australia.
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Taguchi K, Watanabe Y, Tsujimura A, Tanaka M. Brain region-dependent differential expression of alpha-synuclein. J Comp Neurol 2015; 524:1236-58. [DOI: 10.1002/cne.23901] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2015] [Revised: 09/09/2015] [Accepted: 09/09/2015] [Indexed: 12/24/2022]
Affiliation(s)
- Katsutoshi Taguchi
- Department of Basic Geriatrics; Kyoto Prefectural University of Medicine; Kawaramachi-Hirokoji, Kamikyo-ku Kyoto Japan
| | - Yoshihisa Watanabe
- Department of Basic Geriatrics; Kyoto Prefectural University of Medicine; Kawaramachi-Hirokoji, Kamikyo-ku Kyoto Japan
| | - Atsushi Tsujimura
- Department of Basic Geriatrics; Kyoto Prefectural University of Medicine; Kawaramachi-Hirokoji, Kamikyo-ku Kyoto Japan
| | - Masaki Tanaka
- Department of Basic Geriatrics; Kyoto Prefectural University of Medicine; Kawaramachi-Hirokoji, Kamikyo-ku Kyoto Japan
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Splicing Regulation of Pro-Inflammatory Cytokines and Chemokines: At the Interface of the Neuroendocrine and Immune Systems. Biomolecules 2015; 5:2073-100. [PMID: 26371053 PMCID: PMC4598789 DOI: 10.3390/biom5032073] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 08/28/2015] [Indexed: 01/13/2023] Open
Abstract
Alternative splicing plays a key role in posttranscriptional regulation of gene expression, allowing a single gene to encode multiple protein isoforms. As such, alternative splicing amplifies the coding capacity of the genome enormously, generates protein diversity, and alters protein function. More than 90% of human genes undergo alternative splicing, and alternative splicing is especially prevalent in the nervous and immune systems, tissues where cells need to react swiftly and adapt to changes in the environment through carefully regulated mechanisms of cell differentiation, migration, targeting, and activation. Given its prevalence and complexity, this highly regulated mode of gene expression is prone to be affected by disease. In the following review, we look at how alternative splicing of signaling molecules—cytokines and their receptors—changes in different pathological conditions, from chronic inflammation to neurologic disorders, providing means of functional interaction between the immune and neuroendocrine systems. Switches in alternative splicing patterns can be very dynamic and can produce signaling molecules with distinct or antagonistic functions and localization to different subcellular compartments. This newly discovered link expands our understanding of the biology of immune and neuroendocrine cells, and has the potential to open new windows of opportunity for treatment of neurodegenerative disorders.
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Splicing: is there an alternative contribution to Parkinson's disease? Neurogenetics 2015; 16:245-63. [PMID: 25980689 PMCID: PMC4573652 DOI: 10.1007/s10048-015-0449-x] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 05/04/2015] [Indexed: 12/21/2022]
Abstract
Alternative splicing is a crucial mechanism of gene expression regulation that enormously increases the coding potential of our genome and represents an intermediate step between messenger RNA (mRNA) transcription and protein posttranslational modifications. Alternative splicing occupies a central position in the development and functions of the nervous system. Therefore, its deregulation frequently leads to several neurological human disorders. In the present review, we provide an updated overview on the impact of alternative splicing in Parkinson's disease (PD), the second most common neurodegenerative disorder worldwide. We will describe the alternative splicing of major PD-linked genes by collecting the current evidences about this intricate and not carefully explored aspect. Assessing the role of this mechanism on PD pathobiology may represent a central step toward an improved understanding of this complex disease.
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28
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Giráldez-Pérez RM, Antolín-Vallespín M, Muñoz MD, Sánchez-Capelo A. Models of α-synuclein aggregation in Parkinson's disease. Acta Neuropathol Commun 2014; 2:176. [PMID: 25497491 PMCID: PMC4272812 DOI: 10.1186/s40478-014-0176-9] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Accepted: 12/04/2014] [Indexed: 12/13/2022] Open
Abstract
Parkinson's disease (PD) is not only characterized by motor disturbances but also, by cognitive, sensory, psychiatric and autonomic dysfunction. It has been proposed that some of these symptoms might be related to the widespread pathology of α-synuclein (α-syn) aggregation in different nuclei of the central and peripheral nervous system. However, the pathogenic formation of α-syn aggregates in different brain areas of PD patients is poorly understood. Most experimental models of PD are valuable to assess specific aspects of its pathogenesis, such as toxin-induced dopaminergic neurodegeneration. However, new models are required that reflect the widespread and progressive formation of α-syn aggregates in different brain areas. Such α-syn aggregation is induced in only a few animal models, for example perikaryon inclusions are found in rats administered rotenone, aggregates with a neuritic morphology develop in mice overexpressing either mutated or wild-type α-syn, and in Smad3 deficient mice, aggregates form extensively in the perikaryon and neurites of specific brain nuclei. In this review we focus on α-syn aggregation in the human disorder, its genetics and the availability of experimental models. Indeed, evidences show that dopamine (DA) metabolism may be related to α-syn and its conformational plasticity, suggesting an interesting link between the two pathological hallmarks of PD: dopaminergic neurodegeneration and Lewy body (LB) formation.
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Affiliation(s)
- Rosa María Giráldez-Pérez
- />CIBERNED - Ser. Neurobiología – Investigación, Hospital Universitario Ramón y Cajal – IRYCIS, Ctra. Colmenar Viejo Km 9, 28034 Madrid, Spain
- />Departamento Fisiología, Facultad de Farmacia, Universidad de Sevilla, Sevilla, Spain
| | - Mónica Antolín-Vallespín
- />CIBERNED - Ser. Neurobiología – Investigación, Hospital Universitario Ramón y Cajal – IRYCIS, Ctra. Colmenar Viejo Km 9, 28034 Madrid, Spain
| | - María Dolores Muñoz
- />Unidad de Neurología Experimental, Hospital Universitario Ramón y Cajal – IRYCIS, Ctra. Colmenar Viejo Km 9, 28034 Madrid, Spain
| | - Amelia Sánchez-Capelo
- />CIBERNED - Ser. Neurobiología – Investigación, Hospital Universitario Ramón y Cajal – IRYCIS, Ctra. Colmenar Viejo Km 9, 28034 Madrid, Spain
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