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Jin M, Wang S, Gao X, Zou Z, Hirotsune S, Sun L. Pathological and physiological functional cross-talks of α-synuclein and tau in the central nervous system. Neural Regen Res 2024; 19:855-862. [PMID: 37843221 PMCID: PMC10664117 DOI: 10.4103/1673-5374.382231] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 05/05/2023] [Accepted: 07/12/2023] [Indexed: 10/17/2023] Open
Abstract
α-Synuclein and tau are abundant multifunctional brain proteins that are mainly expressed in the presynaptic and axonal compartments of neurons, respectively. Previous works have revealed that intracellular deposition of α-synuclein and/or tau causes many neurodegenerative disorders, including Alzheimer's disease and Parkinson's disease. Despite intense investigation, the normal physiological functions and roles of α-synuclein and tau are still unclear, owing to the fact that mice with knockout of either of these proteins do not present apparent phenotypes. Interestingly, the co-occurrence of α-synuclein and tau aggregates was found in post-mortem brains with synucleinopathies and tauopathies, some of which share similarities in clinical manifestations. Furthermore, the direct interaction of α-synuclein with tau is considered to promote the fibrillization of each of the proteins in vitro and in vivo. On the other hand, our recent findings have revealed that α-synuclein and tau are cooperatively involved in brain development in a stage-dependent manner. These findings indicate strong cross-talk between the two proteins in physiology and pathology. In this review, we provide a summary of the recent findings on the functional roles of α-synuclein and tau in the physiological conditions and pathogenesis of neurodegenerative diseases. A deep understanding of the interplay between α-synuclein and tau in physiological and pathological conditions might provide novel targets for clinical diagnosis and therapeutic strategies to treat neurodegenerative diseases.
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Affiliation(s)
- Mingyue Jin
- Guangxi Key Laboratory of Brain and Cognitive Neuroscience, Guilin Medical University, Guilin, Guangxi Zhuang Autonomous Region, China
- Department of Genetic Disease Research, Osaka Metropolitan University Graduate School of Medicine, Osaka, Japan
| | - Shengming Wang
- Department of Genetic Disease Research, Osaka Metropolitan University Graduate School of Medicine, Osaka, Japan
| | - Xiaodie Gao
- Guangxi Key Laboratory of Brain and Cognitive Neuroscience, Guilin Medical University, Guilin, Guangxi Zhuang Autonomous Region, China
| | - Zhenyou Zou
- Department of Scientific Research, Brain Hospital of Guangxi Zhuang Autonomous Region, Liuzhou, Guangxi Zhuang Autonomous Region, China
| | - Shinji Hirotsune
- Department of Genetic Disease Research, Osaka Metropolitan University Graduate School of Medicine, Osaka, Japan
| | - Liyuan Sun
- Guangxi Key Laboratory of Brain and Cognitive Neuroscience, Guilin Medical University, Guilin, Guangxi Zhuang Autonomous Region, China
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2
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Calogero AM, Basellini MJ, Isilgan HB, Longhena F, Bellucci A, Mazzetti S, Rolando C, Pezzoli G, Cappelletti G. Acetylated α-Tubulin and α-Synuclein: Physiological Interplay and Contribution to α-Synuclein Oligomerization. Int J Mol Sci 2023; 24:12287. [PMID: 37569662 PMCID: PMC10418364 DOI: 10.3390/ijms241512287] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 07/26/2023] [Accepted: 07/28/2023] [Indexed: 08/13/2023] Open
Abstract
Emerging evidence supports that altered α-tubulin acetylation occurs in Parkinson's disease (PD), a neurodegenerative disorder characterized by the deposition of α-synuclein fibrillary aggregates within Lewy bodies and nigrostriatal neuron degeneration. Nevertheless, studies addressing the interplay between α-tubulin acetylation and α-synuclein are lacking. Here, we investigated the relationship between α-synuclein and microtubules in primary midbrain murine neurons and the substantia nigra of post-mortem human brains. Taking advantage of immunofluorescence and Proximity Ligation Assay (PLA), a method allowing us to visualize protein-protein interactions in situ, combined with confocal and super-resolution microscopy, we found that α-synuclein and acetylated α-tubulin colocalized and were in close proximity. Next, we employed an α-synuclein overexpressing cellular model and tested the role of α-tubulin acetylation in α-synuclein oligomer formation. We used the α-tubulin deacetylase HDAC6 inhibitor Tubacin to modulate α-tubulin acetylation, and we evaluated the presence of α-synuclein oligomers by PLA. We found that the increase in acetylated α-tubulin significantly induced α-synuclein oligomerization. In conclusion, we unraveled the link between acetylated α-tubulin and α-synuclein and demonstrated that α-tubulin acetylation could trigger the early step of α-synuclein aggregation. These data suggest that the proper regulation of α-tubulin acetylation might be considered a therapeutic strategy to take on PD.
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Affiliation(s)
- Alessandra Maria Calogero
- Department of Biosciences, Università degli Studi di Milano, 20133 Milan, Italy; (M.J.B.); (H.B.I.); (S.M.); (C.R.)
- Fondazione Grigioni per il Morbo di Parkinson, 20125 Milan, Italy;
| | - Milo Jarno Basellini
- Department of Biosciences, Università degli Studi di Milano, 20133 Milan, Italy; (M.J.B.); (H.B.I.); (S.M.); (C.R.)
| | - Huseyin Berkcan Isilgan
- Department of Biosciences, Università degli Studi di Milano, 20133 Milan, Italy; (M.J.B.); (H.B.I.); (S.M.); (C.R.)
| | - Francesca Longhena
- Department of Molecular and Translational Medicine, University of Brescia, 25123 Brescia, Italy; (F.L.); (A.B.)
| | - Arianna Bellucci
- Department of Molecular and Translational Medicine, University of Brescia, 25123 Brescia, Italy; (F.L.); (A.B.)
| | - Samanta Mazzetti
- Department of Biosciences, Università degli Studi di Milano, 20133 Milan, Italy; (M.J.B.); (H.B.I.); (S.M.); (C.R.)
- Fondazione Grigioni per il Morbo di Parkinson, 20125 Milan, Italy;
| | - Chiara Rolando
- Department of Biosciences, Università degli Studi di Milano, 20133 Milan, Italy; (M.J.B.); (H.B.I.); (S.M.); (C.R.)
| | - Gianni Pezzoli
- Fondazione Grigioni per il Morbo di Parkinson, 20125 Milan, Italy;
- Parkinson Institute, ASST-Pini-CTO, 20126 Milan, Italy
| | - Graziella Cappelletti
- Department of Biosciences, Università degli Studi di Milano, 20133 Milan, Italy; (M.J.B.); (H.B.I.); (S.M.); (C.R.)
- Center of Excellence on Neurodegenerative Diseases, Università degli Studi di Milano, 20133 Milan, Italy
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Kuznetsov IA, Kuznetsov AV. Dynein Dysfunction Prevents Maintenance of High Concentrations of Slow Axonal Transport Cargos at the Axon Terminal: A Computational Study. J Biomech Eng 2023; 145:071001. [PMID: 36795013 PMCID: PMC10158974 DOI: 10.1115/1.4056915] [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: 07/03/2022] [Revised: 02/06/2023] [Accepted: 02/08/2023] [Indexed: 02/17/2023]
Abstract
Here, we report computational studies of bidirectional transport in an axon, specifically focusing on predictions when the retrograde motor becomes dysfunctional. We are motivated by reports that mutations in dynein-encoding genes can cause diseases associated with peripheral motor and sensory neurons, such as type 2O Charcot-Marie-Tooth disease. We use two different models to simulate bidirectional transport in an axon: an anterograde-retrograde model, which neglects passive transport by diffusion in the cytosol, and a full slow transport model, which includes passive transport by diffusion in the cytosol. As dynein is a retrograde motor, its dysfunction should not directly influence anterograde transport. However, our modeling results unexpectedly predict that slow axonal transport fails to transport cargos against their concentration gradient without dynein. The reason is the lack of a physical mechanism for the reverse information flow from the axon terminal, which is required so that the cargo concentration at the terminal could influence the cargo concentration distribution in the axon. Mathematically speaking, to achieve a prescribed concentration at the terminal, equations governing cargo transport must allow for the imposition of a boundary condition postulating the cargo concentration at the terminal. Perturbation analysis for the case when the retrograde motor velocity becomes close to zero predicts uniform cargo distributions along the axon. The obtained results explain why slow axonal transport must be bidirectional to allow for the maintenance of concentration gradients along the axon length. Our result is limited to small cargo diffusivity, which is a reasonable assumption for many slow axonal transport cargos (such as cytosolic and cytoskeletal proteins, neurofilaments, actin, and microtubules) which are transported as large multiprotein complexes or polymers.
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Affiliation(s)
- Ivan A. Kuznetsov
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104; Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104
| | - Andrey V. Kuznetsov
- Department of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh, NC 27695-7910
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Abstract
Neurons are markedly compartmentalized, which makes them reliant on axonal transport to maintain their health. Axonal transport is important for anterograde delivery of newly synthesized macromolecules and organelles from the cell body to the synapse and for the retrograde delivery of signaling endosomes and autophagosomes for degradation. Dysregulation of axonal transport occurs early in neurodegenerative diseases and plays a key role in axonal degeneration. Here, we provide an overview of mechanisms for regulation of axonal transport; discuss how these mechanisms are disrupted in neurodegenerative diseases including Alzheimer's disease, Parkinson's disease, Huntington's disease, hereditary spastic paraplegia, amyotrophic lateral sclerosis, and Charcot-Marie-Tooth disease; and discuss therapeutic approaches targeting axonal transport.
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Griffin TA, Schnier PD, Cleveland EM, Newberry RW, Becker J, Carlson GA. Fibril treatment changes protein interactions of tau and α-synuclein in human neurons. J Biol Chem 2023; 299:102888. [PMID: 36634849 PMCID: PMC9978635 DOI: 10.1016/j.jbc.2023.102888] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 12/07/2022] [Accepted: 01/02/2023] [Indexed: 01/11/2023] Open
Abstract
In several neurodegenerative disorders, the neuronal proteins tau and α-synuclein adopt aggregation-prone conformations capable of replicating within and between cells. To better understand how these conformational changes drive neuropathology, we compared the interactomes of tau and α-synuclein in the presence or the absence of recombinant fibril seeds. Human embryonic stem cells with an inducible neurogenin-2 transgene were differentiated into glutamatergic neurons expressing (1) WT 0N4R tau, (2) mutant (P301L) 0N4R tau, (3) WT α-synuclein, or (4) mutant (A53T) α-synuclein, each genetically fused to a promiscuous biotin ligase (BioID2). Neurons expressing unfused BioID2 served as controls. After treatment with fibrils or PBS, interacting proteins were labeled with biotin in situ and quantified using mass spectrometry via tandem mass tag labeling. By comparing interactions in mutant versus WT neurons and in fibril- versus PBS-treated neurons, we observed changes in protein interactions that are likely relevant to disease progression. We identified 45 shared interactors, suggesting that tau and α-synuclein function within some of the same pathways. Potential loci of shared interactions include microtubules, Wnt signaling complexes, and RNA granules. Following fibril treatment, physiological interactions decreased, whereas other interactions, including those between tau and 14-3-3 η, increased. We confirmed that 14-3-3 proteins, which are known to colocalize with protein aggregates during neurodegeneration, can promote or inhibit tau aggregation in vitro depending on the specific combination of 14-3-3 isoform and tau sequence.
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Affiliation(s)
- Tagan A Griffin
- Institute for Neurodegenerative Diseases, Weill Institute for Neurosciences, University of California, San Francisco, California, USA
| | - Paul D Schnier
- Institute for Neurodegenerative Diseases, Weill Institute for Neurosciences, University of California, San Francisco, California, USA; Department of Neurology, Weill Institute for Neurosciences, University of California, San Francisco, California, USA
| | - Elisa M Cleveland
- Institute for Neurodegenerative Diseases, Weill Institute for Neurosciences, University of California, San Francisco, California, USA
| | - Robert W Newberry
- Institute for Neurodegenerative Diseases, Weill Institute for Neurosciences, University of California, San Francisco, California, USA; Department of Pharmaceutical Chemistry, University of California, San Francisco, California, USA
| | - Julia Becker
- Institute for Neurodegenerative Diseases, Weill Institute for Neurosciences, University of California, San Francisco, California, USA
| | - George A Carlson
- Institute for Neurodegenerative Diseases, Weill Institute for Neurosciences, University of California, San Francisco, California, USA; Department of Neurology, Weill Institute for Neurosciences, University of California, San Francisco, California, USA.
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6
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Mazzetti S, Calogero AM, Pezzoli G, Cappelletti G. Cross-talk between α-synuclein and the microtubule cytoskeleton in neurodegeneration. Exp Neurol 2023; 359:114251. [PMID: 36243059 DOI: 10.1016/j.expneurol.2022.114251] [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: 05/17/2022] [Revised: 10/03/2022] [Accepted: 10/06/2022] [Indexed: 12/30/2022]
Abstract
Looking at the puzzle that depicts the molecular determinants in neurodegeneration, many pieces are lacking and multiple interconnections among key proteins and intracellular pathways still remain unclear. Here we focus on the concerted action of α-synuclein and the microtubule cytoskeleton, whose interplay, indeed, is emerging but remains largely unexplored in both its physiology and pathology. α-Synuclein is a key protein involved in neurodegeneration, underlying those diseases termed synucleinopathies. Its propensity to interact with other proteins and structures renders the identification of neuronal death trigger extremely difficult. Conversely, the unbalance of microtubule cytoskeleton in terms of structure, dynamics and function is emerging as a point of convergence in neurodegeneration. Interestingly, α-synuclein and microtubules have been shown to interact and mediate cross-talks with other intracellular structures. This is supported by an increasing amount of evidence ranging from their direct interaction to the engagement of in-common partners and culminating with their respective impact on microtubule-dependent neuronal functions. Last, but not least, it is becoming even more clear that α-synuclein and tubulin work synergically towards pathological aggregation, ultimately resulting in neurodegeneration. In this respect, we supply a novel perspective towards the understanding of α-synuclein biology and, most importantly, of the link between α-synuclein with microtubule cytoskeleton and its impact for neurodegeneration and future development of novel therapeutic strategies.
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Affiliation(s)
- Samanta Mazzetti
- Department of Biosciences, Università degli Studi di Milano, Milan, Italy; Fondazione Grigioni per il Morbo di Parkinson, Milan, Italy
| | | | - Gianni Pezzoli
- Fondazione Grigioni per il Morbo di Parkinson, Milan, Italy
| | - Graziella Cappelletti
- Department of Biosciences, Università degli Studi di Milano, Milan, Italy; Center of Excellence on Neurodegenerative Diseases, Università degli Studi di Milano, Milano, Italy.
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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: 22] [Impact Index Per Article: 11.0] [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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Jin M, Matsumoto S, Ayaki T, Yamakado H, Taguchi T, Togawa N, Konno A, Hirai H, Nakajima H, Komai S, Ishida R, Chiba S, Takahashi R, Takao T, Hirotsune S. DOPAnization of tyrosine in α-synuclein by tyrosine hydroxylase leads to the formation of oligomers. Nat Commun 2022; 13:6880. [PMID: 36371400 PMCID: PMC9653393 DOI: 10.1038/s41467-022-34555-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 10/27/2022] [Indexed: 11/15/2022] Open
Abstract
Parkinson's disease is a progressive neurodegenerative disorder characterized by the preferential loss of tyrosine hydroxylase (TH)-expressing dopaminergic neurons in the substantia nigra. Although the abnormal accumulation and aggregation of α-synuclein have been implicated in the pathogenesis of Parkinson's disease, the underlying mechanisms remain largely elusive. Here, we found that TH converts Tyr136 in α-synuclein into dihydroxyphenylalanine (DOPA; Y136DOPA) through mass spectrometric analysis. Y136DOPA modification was clearly detected by a specific antibody in the dopaminergic neurons of α-synuclein-overexpressing mice as well as human α-synucleinopathies. Furthermore, dopanized α-synuclein tended to form oligomers rather than large fibril aggregates and significantly enhanced neurotoxicity. Our findings suggest that the dopanization of α-synuclein by TH may contribute to oligomer and/or seed formation causing neurodegeneration with the potential to shed light on the pathogenesis of Parkinson's disease.
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Affiliation(s)
- Mingyue Jin
- Department of Genetic Disease Research, Osaka Metropolitan University Graduate School of Medicine, Abeno-ku, Osaka 545-8585 Japan ,grid.443385.d0000 0004 1798 9548Guangxi Key Laboratory of Brain and Cognitive Neuroscience, Guilin Medical University, Guilin, Guangxi 541199 China
| | - Sakiko Matsumoto
- Department of Genetic Disease Research, Osaka Metropolitan University Graduate School of Medicine, Abeno-ku, Osaka 545-8585 Japan
| | - Takashi Ayaki
- grid.258799.80000 0004 0372 2033Department of Neurology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8507 Japan
| | - Hodaka Yamakado
- grid.258799.80000 0004 0372 2033Department of Neurology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8507 Japan
| | - Tomoyuki Taguchi
- grid.258799.80000 0004 0372 2033Department of Neurology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8507 Japan
| | - Natsuko Togawa
- grid.258799.80000 0004 0372 2033Department of Neurology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8507 Japan
| | - Ayumu Konno
- grid.256642.10000 0000 9269 4097Department of Neurophysiology & Neural Repair, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511 Japan
| | - Hirokazu Hirai
- grid.256642.10000 0000 9269 4097Department of Neurophysiology & Neural Repair, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511 Japan
| | - Hiroshi Nakajima
- Division of Molecular Materials Science, Osaka Metropolitan University Graduate School of Science, Sumiyoshi-ku, Osaka 558-8585 Japan
| | - Shoji Komai
- grid.260493.a0000 0000 9227 2257Department of Science and Technology, Nara Institute of Science Technology, Ikoma, Nara 630-0192 Japan
| | - Ryuichi Ishida
- Department of Genetic Disease Research, Osaka Metropolitan University Graduate School of Medicine, Abeno-ku, Osaka 545-8585 Japan
| | - Syuhei Chiba
- Department of Genetic Disease Research, Osaka Metropolitan University Graduate School of Medicine, Abeno-ku, Osaka 545-8585 Japan
| | - Ryosuke Takahashi
- grid.258799.80000 0004 0372 2033Department of Neurology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8507 Japan
| | - Toshifumi Takao
- grid.136593.b0000 0004 0373 3971Laboratory of Protein Profiling and Functional Proteomics, Osaka University Institute for Protein Research, Suita, Osaka 565-0871 Japan
| | - Shinji Hirotsune
- Department of Genetic Disease Research, Osaka Metropolitan University Graduate School of Medicine, Abeno-ku, Osaka 545-8585 Japan
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Jin M, Matsumoto S, Ayaki T, Yamakado H, Taguchi T, Togawa N, Konno A, Hirai H, Nakajima H, Komai S, Ishida R, Chiba S, Takahashi R, Takao T, Hirotsune S. DOPAnization of tyrosine in α-synuclein by tyrosine hydroxylase leads to the formation of oligomers. Nat Commun 2022. [PMID: 36371400 DOI: 10.1038/s41467-022-34555-4.pmid:36371400;pmcid:pmc9653393] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2023] Open
Abstract
Parkinson's disease is a progressive neurodegenerative disorder characterized by the preferential loss of tyrosine hydroxylase (TH)-expressing dopaminergic neurons in the substantia nigra. Although the abnormal accumulation and aggregation of α-synuclein have been implicated in the pathogenesis of Parkinson's disease, the underlying mechanisms remain largely elusive. Here, we found that TH converts Tyr136 in α-synuclein into dihydroxyphenylalanine (DOPA; Y136DOPA) through mass spectrometric analysis. Y136DOPA modification was clearly detected by a specific antibody in the dopaminergic neurons of α-synuclein-overexpressing mice as well as human α-synucleinopathies. Furthermore, dopanized α-synuclein tended to form oligomers rather than large fibril aggregates and significantly enhanced neurotoxicity. Our findings suggest that the dopanization of α-synuclein by TH may contribute to oligomer and/or seed formation causing neurodegeneration with the potential to shed light on the pathogenesis of Parkinson's disease.
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Affiliation(s)
- Mingyue Jin
- Department of Genetic Disease Research, Osaka Metropolitan University Graduate School of Medicine, Abeno-ku, Osaka, 545-8585, Japan
- Guangxi Key Laboratory of Brain and Cognitive Neuroscience, Guilin Medical University, Guilin, Guangxi, 541199, China
| | - Sakiko Matsumoto
- Department of Genetic Disease Research, Osaka Metropolitan University Graduate School of Medicine, Abeno-ku, Osaka, 545-8585, Japan
| | - Takashi Ayaki
- Department of Neurology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Hodaka Yamakado
- Department of Neurology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Tomoyuki Taguchi
- Department of Neurology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Natsuko Togawa
- Department of Neurology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Ayumu Konno
- Department of Neurophysiology & Neural Repair, Gunma University Graduate School of Medicine, Maebashi, Gunma, 371-8511, Japan
| | - Hirokazu Hirai
- Department of Neurophysiology & Neural Repair, Gunma University Graduate School of Medicine, Maebashi, Gunma, 371-8511, Japan
| | - Hiroshi Nakajima
- Division of Molecular Materials Science, Osaka Metropolitan University Graduate School of Science, Sumiyoshi-ku, Osaka, 558-8585, Japan
| | - Shoji Komai
- Department of Science and Technology, Nara Institute of Science Technology, Ikoma, Nara, 630-0192, Japan
| | - Ryuichi Ishida
- Department of Genetic Disease Research, Osaka Metropolitan University Graduate School of Medicine, Abeno-ku, Osaka, 545-8585, Japan
| | - Syuhei Chiba
- Department of Genetic Disease Research, Osaka Metropolitan University Graduate School of Medicine, Abeno-ku, Osaka, 545-8585, Japan
| | - Ryosuke Takahashi
- Department of Neurology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Toshifumi Takao
- Laboratory of Protein Profiling and Functional Proteomics, Osaka University Institute for Protein Research, Suita, Osaka, 565-0871, Japan
| | - Shinji Hirotsune
- Department of Genetic Disease Research, Osaka Metropolitan University Graduate School of Medicine, Abeno-ku, Osaka, 545-8585, Japan.
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Gezen-Ak D, Yurttaş Z, Çamoǧlu T, Dursun E. Could Amyloid-β 1-42 or α-Synuclein Interact Directly with Mitochondrial DNA? A Hypothesis. ACS Chem Neurosci 2022; 13:2803-2812. [PMID: 36125124 PMCID: PMC9542719 DOI: 10.1021/acschemneuro.2c00512] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The amyloid β (Aβ) and the α-synuclein (α-syn) are shown to be translocated into mitochondria. Even though their roles are widely investigated in pathological conditions, information on the presence and functions of Aβ and α-syn in mitochondria in endogenous levels is somewhat limited. We hypothesized that endogenous Aβ fragments or α-syn could interact with mitochondrial DNA (mtDNA) directly or influence RNAs or transcription factors in mitochondria and change the mtDNA transcription profile. In this review, we summarized clues of these possible interactions.
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Affiliation(s)
| | | | | | - Erdinç Dursun
- E.D.: email, ; phone, +90 212 414 30 00/68025, +90 533 339
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11
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Wang S, Fu Y, Miyata T, Matsumoto S, Shinoda T, Itoh K, Harada A, Hirotsune S, Jin M. Functional Cooperation of α-Synuclein and Tau Is Essential for Proper Corticogenesis. J Neurosci 2022; 42:7031-7046. [PMID: 35906071 PMCID: PMC9480882 DOI: 10.1523/jneurosci.0396-22.2022] [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: 02/26/2022] [Revised: 07/07/2022] [Accepted: 07/21/2022] [Indexed: 11/21/2022] Open
Abstract
Alpha-synuclein (αSyn) and tau are abundant multifunctional neuronal proteins, and their intracellular deposits have been linked to many neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease. Despite the disease relevance, their physiological roles remain elusive, as mice with knock-out of either of these genes do not exhibit overt phenotypes. To reveal functional cooperation, we generated αSyn-/-tau-/- double-knock-out mice and characterized the functional cross talk between these proteins during brain development. Intriguingly, deletion of αSyn and tau reduced Notch signaling and accelerated interkinetic nuclear migration of G2 phase at early embryonic stage. This significantly altered the balance between the proliferative and neurogenic divisions of progenitor cells, resulting in an overproduction of early born neurons and enhanced neurogenesis, by which the brain size was enlarged during the embryonic stage in both sexes. On the other hand, a reduction in the number of neural progenitor cells in the middle stage of corticogenesis diminished subsequent gliogenesis in the αSyn-/-tau-/- cortex. Additionally, the expansion and maturation of macroglial cells (astrocytes and oligodendrocytes) were suppressed in the αSyn-/-tau-/- postnatal brain, which in turn reduced the male αSyn-/-tau-/- brain size and cortical thickness to less than the control values. Our study identifies important functional cooperation of αSyn and tau during corticogenesis.SIGNIFICANCE STATEMENT Correct understanding of the physiological functions of αSyn and tau in CNS is critical to elucidate pathogenesis involved in the etiology of neurodegenerative diseases including Alzheimer's disease and Parkinson's disease. We show here that αSyn and tau are cooperatively involved in brain development via maintenance of progenitor cells. αSyn and tau double-knock-out mice exhibited an overproduction of early born neurons and accelerated neurogenesis at early corticogenesis. Furthermore, loss of αSyn and tau also perturbed gliogenesis at later embryonic stage, as well as the subsequent glial expansion and maturation at postnatal brain. Our findings provide new mechanistic insights and extend therapeutic opportunities for neurodegenerative diseases caused by aberrant αSyn and tau.
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Affiliation(s)
- Shengming Wang
- Department of Genetic Disease Research, Osaka Metropolitan University Graduate School of Medicine, Osaka 545-8585, Japan
| | - Yu Fu
- Department of Genetic Disease Research, Osaka Metropolitan University Graduate School of Medicine, Osaka 545-8585, Japan
| | - Takaki Miyata
- Department of Anatomy and Cell Biology, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | - Sakiko Matsumoto
- Department of Genetic Disease Research, Osaka Metropolitan University Graduate School of Medicine, Osaka 545-8585, Japan
| | - Tomoyasu Shinoda
- Department of Anatomy and Cell Biology, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | - Kyoko Itoh
- Department of Pathology and Applied Neurobiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Akihiro Harada
- Department of Cell Biology, Graduate School of Medicine, Osaka University, Osaka 565-0871, Japan
| | - Shinji Hirotsune
- Department of Genetic Disease Research, Osaka Metropolitan University Graduate School of Medicine, Osaka 545-8585, Japan
| | - Mingyue Jin
- Department of Genetic Disease Research, Osaka Metropolitan University Graduate School of Medicine, Osaka 545-8585, Japan
- Guangxi Key Laboratory of Brain and Cognitive Neuroscience, Guilin Medical University, Guilin, Guangxi 541199, China
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12
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Kuznetsov IA, Kuznetsov AV. Bidirectional, unlike unidirectional transport, allows transporting axonal cargos against their concentration gradient. J Theor Biol 2022; 546:111161. [DOI: 10.1016/j.jtbi.2022.111161] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Revised: 05/04/2022] [Accepted: 05/06/2022] [Indexed: 11/25/2022]
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13
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Amadeo A, Pizzi S, Comincini A, Modena D, Calogero AM, Madaschi L, Faustini G, Rolando C, Bellucci A, Pezzoli G, Mazzetti S, Cappelletti G. The Association between α-Synuclein and α-Tubulin in Brain Synapses. Int J Mol Sci 2021; 22:ijms22179153. [PMID: 34502063 PMCID: PMC8430732 DOI: 10.3390/ijms22179153] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 08/17/2021] [Accepted: 08/19/2021] [Indexed: 12/14/2022] Open
Abstract
α-synuclein is a small protein that is mainly expressed in the synaptic terminals of nervous tissue. Although its implication in neurodegeneration is well established, the physiological role of α-synuclein remains elusive. Given its involvement in the modulation of synaptic transmission and the emerging role of microtubules at the synapse, the current study aimed at investigating whether α-synuclein becomes involved with this cytoskeletal component at the presynapse. We first analyzed the expression of α-synuclein and its colocalization with α-tubulin in murine brain. Differences were found between cortical and striatal/midbrain areas, with substantia nigra pars compacta and corpus striatum showing the lowest levels of colocalization. Using a proximity ligation assay, we revealed the direct interaction of α-synuclein with α-tubulin in murine and in human brain. Finally, the previously unexplored interaction of the two proteins in vivo at the synapse was disclosed in murine striatal presynaptic boutons through multiple approaches, from confocal spinning disk to electron microscopy. Collectively, our data strongly suggest that the association with tubulin/microtubules might actually be an important physiological function for α-synuclein in the synapse, thus suggesting its potential role in a neuropathological context.
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Affiliation(s)
- Alida Amadeo
- Department of Biosciences, University of Milan, Via Celoria 26, 20126 Milano, Italy; (S.P.); (A.C.); (D.M.); (A.M.C.); (C.R.); (S.M.)
- Center of Excellence on Neurodegenerative Diseases, University of Milan, Via Celoria 26, 20126 Milano, Italy
- Correspondence: (A.A.); (G.C.); Tel.: +39-025-031-4885 (A.A.); +39-025-031-4752 (G.C.)
| | - Sara Pizzi
- Department of Biosciences, University of Milan, Via Celoria 26, 20126 Milano, Italy; (S.P.); (A.C.); (D.M.); (A.M.C.); (C.R.); (S.M.)
| | - Alessandro Comincini
- Department of Biosciences, University of Milan, Via Celoria 26, 20126 Milano, Italy; (S.P.); (A.C.); (D.M.); (A.M.C.); (C.R.); (S.M.)
| | - Debora Modena
- Department of Biosciences, University of Milan, Via Celoria 26, 20126 Milano, Italy; (S.P.); (A.C.); (D.M.); (A.M.C.); (C.R.); (S.M.)
| | - Alessandra Maria Calogero
- Department of Biosciences, University of Milan, Via Celoria 26, 20126 Milano, Italy; (S.P.); (A.C.); (D.M.); (A.M.C.); (C.R.); (S.M.)
| | - Laura Madaschi
- UNITECH NOLIMITS, University of Milan, Via Celoria 26, 20133 Milan, Italy;
| | - Gaia Faustini
- Division of Pharmacology, Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy; (G.F.); (A.B.)
| | - Chiara Rolando
- Department of Biosciences, University of Milan, Via Celoria 26, 20126 Milano, Italy; (S.P.); (A.C.); (D.M.); (A.M.C.); (C.R.); (S.M.)
| | - Arianna Bellucci
- Division of Pharmacology, Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy; (G.F.); (A.B.)
| | - Gianni Pezzoli
- Fondazione Grigioni per il Morbo di Parkinson, Via Zuretti 35, 20125 Milano, Italy;
| | - Samanta Mazzetti
- Department of Biosciences, University of Milan, Via Celoria 26, 20126 Milano, Italy; (S.P.); (A.C.); (D.M.); (A.M.C.); (C.R.); (S.M.)
- Fondazione Grigioni per il Morbo di Parkinson, Via Zuretti 35, 20125 Milano, Italy;
| | - Graziella Cappelletti
- Department of Biosciences, University of Milan, Via Celoria 26, 20126 Milano, Italy; (S.P.); (A.C.); (D.M.); (A.M.C.); (C.R.); (S.M.)
- Center of Excellence on Neurodegenerative Diseases, University of Milan, Via Celoria 26, 20126 Milano, Italy
- Correspondence: (A.A.); (G.C.); Tel.: +39-025-031-4885 (A.A.); +39-025-031-4752 (G.C.)
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14
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Tau and Alpha Synuclein Synergistic Effect in Neurodegenerative Diseases: When the Periphery Is the Core. Int J Mol Sci 2020; 21:ijms21145030. [PMID: 32708732 PMCID: PMC7404325 DOI: 10.3390/ijms21145030] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 07/13/2020] [Accepted: 07/14/2020] [Indexed: 02/08/2023] Open
Abstract
In neuronal cells, tau is a microtubule-associated protein placed in axons and alpha synuclein is enriched at presynaptic terminals. They display a propensity to form pathologic aggregates, which are considered the underlying cause of Alzheimer's and Parkinson's diseases. Their functional impairment induces loss of axonal transport, synaptic and mitochondrial disarray, leading to a "dying back" pattern of degeneration, which starts at the periphery of cells. In addition, pathologic spreading of alpha-synuclein from the peripheral nervous system to the brain through anatomical connectivity has been demonstrated for Parkinson's disease. Thus, examination of the extent and types of tau and alpha-synuclein in peripheral tissues and their relation to brain neurodegenerative diseases is of relevance since it may provide insights into patterns of protein aggregation and neurodegeneration. Moreover, peripheral nervous tissues are easily accessible in-vivo and can play a relevant role in the early diagnosis of these conditions. Up-to-date investigations of tau species in peripheral tissues are scant and have mainly been restricted to rodents, whereas, more evidence is available on alpha synuclein in peripheral tissues. Here we aim to review the literature on the functional role of tau and alpha synuclein in physiological conditions and disease at the axonal level, their distribution in peripheral tissues, and discuss possible commonalities/diversities as well as their interaction in proteinopathies.
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15
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Spencer PS. Neuroprotein Targets of γ-Diketone Metabolites of Aliphatic and Aromatic Solvents That Induce Central-Peripheral Axonopathy. Toxicol Pathol 2020; 48:411-421. [PMID: 32162603 DOI: 10.1177/0192623320910960] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Peripheral neuropathy associated with chronic occupational and deliberate overexposure to neurotoxic organic solvents results from axonal degeneration in the central and peripheral nervous system. Human and experimental studies show that axonopathy is triggered by the action of neuroprotein-reactive γ-diketone metabolites formed from exposure to certain aliphatic solvents (n-hexane, 2-hexanone) and aromatic compounds (1,2-diethylbenzene, 1,2-4-triethylbenzene, 6-acetyl-1,1,4,4-tetramethyl-7-ethyl-1,2,3,4-tetralin). Neuroprotein susceptibility is related primarily to their differential content of lysine, the ∊-amino group of which is targeted by γ-diketones. Specific neuroprotein targets have been identified, and the sequence of molecular mechanisms leading to axonal pathology has been illuminated. While occupational n-hexane neuropathy continues to be reported, lessons learned from its experimental study may have relevance to other causes of peripheral neuropathy, including those associated with aging and diabetes mellitus.
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Affiliation(s)
- Peter S Spencer
- Oregon Institute of Occupational Health Sciences and Department of Neurology, School of Medicine, Oregon Health & Science University, Portland, OR, USA
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16
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Calogero AM, Mazzetti S, Pezzoli G, Cappelletti G. Neuronal microtubules and proteins linked to Parkinson's disease: a relevant interaction? Biol Chem 2020; 400:1099-1112. [PMID: 31256059 DOI: 10.1515/hsz-2019-0142] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 06/24/2019] [Indexed: 12/13/2022]
Abstract
Neuronal microtubules are key determinants of cell morphology, differentiation, migration and polarity, and contribute to intracellular trafficking along axons and dendrites. Microtubules are strictly regulated and alterations in their dynamics can lead to catastrophic effects in the neuron. Indeed, the importance of the microtubule cytoskeleton in many human diseases is emerging. Remarkably, a growing body of evidence indicates that microtubule defects could be linked to Parkinson's disease pathogenesis. Only a few of the causes of the progressive neuronal loss underlying this disorder have been identified. They include gene mutations and toxin exposure, but the trigger leading to neurodegeneration is still unknown. In this scenario, the evidence showing that mutated proteins in Parkinson's disease are involved in the regulation of the microtubule cytoskeleton is intriguing. Here, we focus on α-Synuclein, Parkin and Leucine-rich repeat kinase 2 (LRRK2), the three main proteins linked to the familial forms of the disease. The aim is to dissect their interaction with tubulin and microtubules in both physiological and pathological conditions, in which these proteins are overexpressed, mutated or absent. We highlight the relevance of such an interaction and suggest that these proteins could trigger neurodegeneration via defective regulation of the microtubule cytoskeleton.
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Affiliation(s)
- Alessandra M Calogero
- Department of Biosciences, Università degli Studi di Milano, via Celoria 26, I-20133 Milan, Italy
| | - Samanta Mazzetti
- Department of Biosciences, Università degli Studi di Milano, via Celoria 26, I-20133 Milan, Italy.,Fondazione Grigioni per il Morbo di Parkinson, via Zuretti 35, I-20135 Milan, Italy
| | - Gianni Pezzoli
- Fondazione Grigioni per il Morbo di Parkinson, via Zuretti 35, I-20135 Milan, Italy.,Parkinson Institute, ASST "G.Pini-CTO", via Bignami 1, I-20133 Milan, Italy
| | - Graziella Cappelletti
- Department of Biosciences, Università degli Studi di Milano, via Celoria 26, I-20133 Milan, Italy.,Center of Excellence on Neurodegenerative Diseases, Università degli Studi di Milano, via Balzaretti, I-20133 Milan, Italy
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17
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Trushina NI, Mulkidjanian AY, Brandt R. The microtubule skeleton and the evolution of neuronal complexity in vertebrates. Biol Chem 2020; 400:1163-1179. [PMID: 31116700 DOI: 10.1515/hsz-2019-0149] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 04/17/2019] [Indexed: 12/21/2022]
Abstract
The evolution of a highly developed nervous system is mirrored by the ability of individual neurons to develop increased morphological complexity. As microtubules (MTs) are crucially involved in neuronal development, we tested the hypothesis that the evolution of complexity is driven by an increasing capacity of the MT system for regulated molecular interactions as it may be implemented by a higher number of molecular players and a greater ability of the individual molecules to interact. We performed bioinformatics analysis on different classes of components of the vertebrate neuronal MT cytoskeleton. We show that the number of orthologs of tubulin structure proteins, MT-binding proteins and tubulin-sequestering proteins expanded during vertebrate evolution. We observed that protein diversity of MT-binding and tubulin-sequestering proteins increased by alternative splicing. In addition, we found that regions of the MT-binding protein tau and MAP6 displayed a clear increase in disorder extent during evolution. The data provide evidence that vertebrate evolution is paralleled by gene expansions, changes in alternative splicing and evolution of coding sequences of components of the MT system. The results suggest that in particular evolutionary changes in tubulin-structure proteins, MT-binding proteins and tubulin-sequestering proteins were prominent drivers for the development of increased neuronal complexity.
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Affiliation(s)
- Nataliya I Trushina
- Department of Neurobiology, University of Osnabrück, Barbarastraße 11, D-49076 Osnabrück, Germany
| | - Armen Y Mulkidjanian
- Department of Physics, University of Osnabrück, Barbarastraße 7, D-49076 Osnabrück, Germany.,A.N. Belozersky Institute of Physico-Chemical Biology and School of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Roland Brandt
- Department of Neurobiology, University of Osnabrück, Barbarastraße 11, D-49076 Osnabrück, Germany.,Center for Cellular Nanoanalytics, University of Osnabrück, Barbarastraße 11, D-49076 Osnabrück, Germany.,Institute of Cognitive Science, University of Osnabrück, Barbarastraße 11, D-49076 Osnabrück, Germany
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18
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Oláh J, Ovádi J. Pharmacological targeting of α-synuclein and TPPP/p25 in Parkinson's disease: challenges and opportunities in a Nutshell. FEBS Lett 2019; 593:1641-1653. [PMID: 31148150 DOI: 10.1002/1873-3468.13464] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 05/20/2019] [Accepted: 05/21/2019] [Indexed: 01/10/2023]
Abstract
With the aging of population, neurological disorders, and especially disorders involving defects in protein conformation (also known as proteopathies) pose a serious socio-economic problem. So far there is no effective treatment for most proteopathies, including Parkinson's disease (PD). The mechanism underlying PD pathogenesis is largely unknown, and the hallmark proteins, α-synuclein (SYN) and tubulin polymerization promoting protein (TPPP/p25) are challenging drug targets. These proteins are intrinsically disordered with high conformational plasticity, and have diverse physiological and pathological functions. In the healthy brain, SYN and TPPP/p25 occur in neurons and oligodendrocytes, respectively; however, in PD and multiple system atrophy, they are co-enriched and co-localized in both cell types, thereby marking pathogenesis. Although large inclusions appear at a late disease stage, small, soluble assemblies of SYN promoted by TPPP/p25 are pathogenic. In the light of these issues, we established a new innovative strategy for the validation of a specific drug target based upon the identification of contact surfaces of the pathological SYN-TPPP/p25 complex that may lead to the development of peptidomimetic foldamers suitable for pharmaceutical intervention.
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Affiliation(s)
- Judit Oláh
- Institute of Enzymology, Research Center for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - Judit Ovádi
- Institute of Enzymology, Research Center for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
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19
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Living in Promiscuity: The Multiple Partners of Alpha-Synuclein at the Synapse in Physiology and Pathology. Int J Mol Sci 2019; 20:ijms20010141. [PMID: 30609739 PMCID: PMC6337145 DOI: 10.3390/ijms20010141] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 12/24/2018] [Accepted: 12/26/2018] [Indexed: 12/18/2022] Open
Abstract
Alpha-synuclein (α-syn) is a small protein that, in neurons, localizes predominantly to presynaptic terminals. Due to elevated conformational plasticity, which can be affected by environmental factors, in addition to undergoing disorder-to-order transition upon interaction with different interactants, α-syn is counted among the intrinsically disordered proteins (IDPs) family. As with many other IDPs, α-syn is considered a hub protein. This function is particularly relevant at synaptic sites, where α-syn is abundant and interacts with many partners, such as monoamine transporters, cytoskeletal components, lipid membranes, chaperones and synaptic vesicles (SV)-associated proteins. These protein–protein and protein–lipid membrane interactions are crucial for synaptic functional homeostasis, and alterations in α-syn can cause disruption of this complex network, and thus a failure of the synaptic machinery. Alterations of the synaptic environment or post-translational modification of α-syn can induce its misfolding, resulting in the formation of oligomers or fibrillary aggregates. These α-syn species are thought to play a pathological role in neurodegenerative disorders with α-syn deposits such as Parkinson’s disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA), which are referred to as synucleinopathies. Here, we aim at revising the complex and promiscuous role of α-syn at synaptic terminals in order to decipher whether α-syn molecular interactants may influence its conformational state, contributing to its aggregation, or whether they are just affected by it.
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20
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Ilan Y. Microtubules: From understanding their dynamics to using them as potential therapeutic targets. J Cell Physiol 2018; 234:7923-7937. [PMID: 30536951 DOI: 10.1002/jcp.27978] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 11/21/2018] [Indexed: 02/06/2023]
Abstract
Microtubules (MT) and actin microfilaments are dynamic cytoskeleton components involved in a range of intracellular processes. MTs play a role in cell division, beating of cilia and flagella, and intracellular transport. Over the past decades, much knowledge has been gained regarding MT function and structure, and its role in underlying disease progression. This makes MT potential therapeutic targets for various disorders. Disturbances in MT and their associated proteins are the underlying cause of diseases such as Alzheimer's disease, cancer, and several genetic diseases. Some of the advances in the field of MT research, as well as the potenti G beta gamma, is needed al uses of MT-targeting agents in various conditions have been reviewed here.
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Affiliation(s)
- Yaron Ilan
- Department of Medicine, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
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21
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Betzer C, Jensen PH. Reduced Cytosolic Calcium as an Early Decisive Cellular State in Parkinson's Disease and Synucleinopathies. Front Neurosci 2018; 12:819. [PMID: 30459551 PMCID: PMC6232531 DOI: 10.3389/fnins.2018.00819] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 10/19/2018] [Indexed: 12/26/2022] Open
Abstract
The more than 30-year-old Calcium hypothesis postulates that dysregulation in calcium dependent processes in the aging brain contributes to its increased vulnerability and this concept has been extended to Alzheimer’s disease and Parkinson’s disease. Central to the hypothesis is that increased levels of intracellular calcium develop and contributes to neuronal demise. We have studied the impact on cells encountering a gradual build-up of aggregated α-synuclein, which is a central process to Parkinson’s disease and other synucleinopathies. Surprisingly, we observed a yet unrecognized phase characterized by a reduced cytosolic calcium in cellular and neuronal models of Parkinson’s disease, caused by α-synuclein aggregates activating the endoplasmic calcium ATPase, SERCA. Counteracting the initial phase with low calcium rescues the subsequent degenerative phase with increased calcium and cell death – and demonstrates this early phase initiates decisive degenerative signals. In this review, we discuss our findings in relation to literature on calcium dysregulation in Parkinson’s disease and dementia.
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Affiliation(s)
- Cristine Betzer
- DANDRITE - Danish Research Institute of Translational Neuroscience, Aarhus University, Aarhus, Denmark.,Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Poul Henning Jensen
- DANDRITE - Danish Research Institute of Translational Neuroscience, Aarhus University, Aarhus, Denmark.,Department of Biomedicine, Aarhus University, Aarhus, Denmark
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22
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Schuman B, Won A, Brand-Arzamendi K, Koprich JB, Wen XY, Howson PA, Brotchie JM, Yip CM. Non-steric-zipper models for pathogenic α-synuclein conformers. APL Bioeng 2018; 2:026105. [PMID: 31069302 PMCID: PMC6481714 DOI: 10.1063/1.5023460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 04/17/2018] [Indexed: 11/14/2022] Open
Abstract
Parkinson's disease neurodegenerative brain tissue exhibits two biophysically distinct α-synuclein fiber isoforms—single stranded fibers that appear to be steric-zippers and double-stranded fibers with an undetermined structure. Herein, we describe a β-helical homology model of α-synuclein that exhibits stability in probabilistic and Monte Carlo simulations as a candidate for stable prional dimer conformers in equilibrium with double-stranded fibers and cytotoxic pore assemblies. Molecular models of β-helical pore assemblies are consistent with α-synucleinA53T transfected rat immunofluorescence epitope maps. Atomic force microscopy reveals that α-synuclein peptides aggregate into anisotropic fibrils lacking the density or circumference of a steric-zipper. Moreover, fibrillation was blocked by mutations designed to hinder β-helical but not steric-zipper conformations. β-helical species provide a structural basis for previously described biophysical properties that are incompatible with a steric-zipper, provide pathogenic mechanisms for familial human α-synuclein mutations, and offer a direct cytotoxic target for therapeutic development.
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Affiliation(s)
- Brock Schuman
- St. Michael's Hospital, 30 Bond Street, Toronto, Ontario M5B 1W8, Canada
| | - Amy Won
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario M5S 3G9, Canada
| | | | - James B. Koprich
- Krembil Institute, Toronto Western Hospital, University Health Network, Toronto, Ontario M5T 2S8, Canada
| | - Xiao-Yan Wen
- St. Michael's Hospital, 30 Bond Street, Toronto, Ontario M5B 1W8, Canada
| | - Patrick A. Howson
- Krembil Institute, Toronto Western Hospital, University Health Network, Toronto, Ontario M5T 2S8, Canada
| | - Jonathan M. Brotchie
- Krembil Institute, Toronto Western Hospital, University Health Network, Toronto, Ontario M5T 2S8, Canada
| | - Christopher M. Yip
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario M5S 3G9, Canada
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