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Szegő ÉM, Boß F, Komnig D, Gärtner C, Höfs L, Shaykhalishahi H, Wördehoff MM, Saridaki T, Schulz JB, Hoyer W, Falkenburger BH. A β-Wrapin Targeting the N-Terminus of α-Synuclein Monomers Reduces Fibril-Induced Aggregation in Neurons. Front Neurosci 2021; 15:696440. [PMID: 34326719 PMCID: PMC8313869 DOI: 10.3389/fnins.2021.696440] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 05/28/2021] [Indexed: 11/25/2022] Open
Abstract
Reducing α-synuclein pathology constitutes a plausible strategy against Parkinson’s disease. As we recently demonstrated, the β-wrapin protein AS69 binds an N-terminal region in monomeric α-synuclein, interferes with fibril nucleation, and reduces α-synuclein aggregation in vitro and in a fruit fly model of α-synuclein toxicity. The aim of this study was to investigate whether AS69 also reduces α-synuclein pathology in mammalian neurons. To induce α-synuclein pathology, primary mouse neurons were exposed to pre-formed fibrils (PFF) of human α-synuclein. PFF were also injected into the striatum of A30P-α-synuclein transgenic mice. The extent of α-synuclein pathology was determined by phospho-α-synuclein staining and by Triton X-100 solubility. The degeneration of neuronal somata, dendrites, and axon terminals was determined by immunohistochemistry. AS69 and PFF were taken up by primary neurons. AS69 did not alter PFF uptake, but AS69 did reduce PFF-induced α-synuclein pathology. PFF injection into mouse striatum led to α-synuclein pathology and dystrophic neurites. Co-injection of AS69 abrogated PFF-induced pathology. AS69 also reduced the PFF-induced degeneration of dopaminergic axon terminals in the striatum and the degeneration of dopaminergic dendrites in the substantia nigra pars reticulata. AS69 reduced the activation of astroglia but not microglia in response to PFF injection. Collectively, AS69 reduced PFF-induced α-synuclein pathology and the associated neurodegeneration in primary neurons and in mouse brain. Our data therefore suggest that small proteins binding the N-terminus of α-synuclein monomers are promising strategies to modify disease progression in Parkinson’s disease.
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Affiliation(s)
- Éva M Szegő
- Department of Neurology, Technische Universität Dresden, Dresden, Germany
| | - Fabian Boß
- Department of Neurology, RWTH Aachen University, Aachen, Germany
| | - Daniel Komnig
- Department of Neurology, RWTH Aachen University, Aachen, Germany
| | - Charlott Gärtner
- Department of Neurology, Technische Universität Dresden, Dresden, Germany
| | - Lennart Höfs
- Department of Neurology, Technische Universität Dresden, Dresden, Germany
| | - Hamed Shaykhalishahi
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany.,Institute of Biological Information Processing (IBI-7), Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Michael M Wördehoff
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | | | - Jörg B Schulz
- Department of Neurology, RWTH Aachen University, Aachen, Germany.,JARA-Institute Molecular Neuroscience and Neuroimaging, Forschungszentrum Jülich GmbH and RWTH Aachen University, Aachen, Germany
| | - Wolfgang Hoyer
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany.,Institute of Biological Information Processing (IBI-7), Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Björn H Falkenburger
- Department of Neurology, Technische Universität Dresden, Dresden, Germany.,Department of Neurology, RWTH Aachen University, Aachen, Germany.,JARA-Institute Molecular Neuroscience and Neuroimaging, Forschungszentrum Jülich GmbH and RWTH Aachen University, Aachen, Germany.,Deutsches Zentrum für Neurodegenerative Erkrankungen, Dresden, Germany
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Yeasts as Complementary Model Systems for the Study of the Pathological Repercussions of Enhanced Synphilin-1 Glycation and Oxidation. Int J Mol Sci 2021; 22:ijms22041677. [PMID: 33562355 PMCID: PMC7915245 DOI: 10.3390/ijms22041677] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 02/01/2021] [Accepted: 02/02/2021] [Indexed: 01/22/2023] Open
Abstract
Synphilin-1 has previously been identified as an interaction partner of α-Synuclein (αSyn), a primary constituent of neurodegenerative disease-linked Lewy bodies. In this study, the repercussions of a disrupted glyoxalase system and aldose reductase function on Synphilin-1 inclusion formation characteristics and cell growth were investigated. To this end, either fluorescent dsRed-tagged or non-tagged human SNCAIP, which encodes the Synphilin-1 protein, was expressed in Saccharomyces cerevisiae and Schizosaccharomyces pombe yeast strains devoid of enzymes Glo1, Glo2, and Gre3. Presented data shows that lack of Glo2 and Gre3 activity in S. cerevisiae increases the formation of large Synphilin-1 inclusions. This correlates with enhanced oxidative stress levels and an inhibitory effect on exponential growth, which is most likely caused by deregulation of autophagic degradation capacity, due to excessive Synphilin-1 aggresome build-up. These findings illustrate the detrimental impact of increased oxidation and glycation on Synphilin-1 inclusion formation. Similarly, polar-localised inclusions were observed in wild-type S. pombe cells and strains deleted for either glo1+ or glo2+. Contrary to S. cerevisiae, however, no growth defects were observed upon expression of SNCAIP. Altogether, our findings show the relevance of yeasts, especially S. cerevisiae, as complementary models to unravel mechanisms contributing to Synphilin-1 pathology in the context of neurodegenerative diseases.
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Komnig D, Dagli TC, Habib P, Zeyen T, Schulz JB, Falkenburger BH. Fingolimod (FTY720) is not protective in the subacute MPTP mouse model of Parkinson's disease and does not lead to a sustainable increase of brain-derived neurotrophic factor. J Neurochem 2018; 147:678-691. [PMID: 30152864 DOI: 10.1111/jnc.14575] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2017] [Revised: 05/29/2018] [Accepted: 08/05/2018] [Indexed: 12/19/2022]
Abstract
Parkinson's disease (PD) is characterized by the loss of midbrain dopaminergic neurons and aggregates of α-synuclein termed Lewy bodies. Fingolimod (FTY720) is an agonist of sphingosine-1 phosphate receptors and an approved oral treatment for multiple sclerosis. Fingolimod elevates brain-derived neurotrophic factor (BDNF), an important neurotrophic factor for dopaminergic neurons. BDNF and fingolimod are beneficial in several animal models of PD. In order to validate the therapeutic potential of fingolimod for the treatment of PD, we tested its effect in the subacute MPTP mouse model of PD. MPTP or vehicle was applied i.p. in doses of 30 mg/kg MPTP on five consecutive days. In order to recapitulate the combination of dopamine loss and α-synuclein aggregates found in PD, MPTP was first administered in Thy1-A30P-α-synuclein transgenic mice. Fingolimod was administered i.p. at a dose of 0.1 mg/kg every second day. Nigrostriatal degeneration was assayed by stereologically counting the number of dopaminergic neurons in the substantia nigra pars compacta, by analysing the concentration of catecholamines and the density of dopaminergic fibres in the striatum. MPTP administration produced a robust nigrostriatal degeneration, comparable to previous studies. Unexpectedly, we found no difference between mice with and without fingolimod treatment, neither at baseline, nor at 14 or 90 days after MPTP. Also, we found no effect of fingolimod in the subacute MPTP mouse model when we used wildtype mice instead of α-synuclein transgenic mice, and no effect with an increased dose of 1 mg/kg fingolimod administered every day. In order to explain these findings, we analysed BDNF regulation by fingolimod. We did find an increase of BDNF protein after a single injection of fingolimod 0.1 or 1.0 mg/kg, but not after multiple injections, indicating that the BDNF response to fingolimod is unsustainable over time. Taken together we did not observe a neuroprotective effect of fingolimod in the subacute MPTP mouse model of PD. We discuss possible explanations for this discrepancy with previous findings and conclude fingolimod might be beneficial for the nonmotor symptoms of PD. OPEN SCIENCE BADGES: This article has received a badge for *Open Materials* and *Open Data* because it provided all relevant information to reproduce the study in the manuscript and because it made the data publicly available. The data can be accessed at https://osf.io/6xgfn/. The complete Open Science Disclosure form for this article can be found at the end of the article. More information about the Open Practices badges can be found at https://cos.io/our-services/open-science-badges/.
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Affiliation(s)
- Daniel Komnig
- Department of Neurology, RWTH Aachen University, Aachen, Germany
| | | | - Pardes Habib
- Department of Neurology, RWTH Aachen University, Aachen, Germany
| | - Thomas Zeyen
- Department of Neurology, RWTH Aachen University, Aachen, Germany
| | - Jörg B Schulz
- Department of Neurology, RWTH Aachen University, Aachen, Germany.,JARA-BRAIN Institute Molecular Neuroscience and Neuroimaging, Forschungszentrum Jülich GmbH and RWTH Aachen University, Aachen, Germany
| | - Björn H Falkenburger
- Department of Neurology, RWTH Aachen University, Aachen, Germany.,JARA-BRAIN Institute Molecular Neuroscience and Neuroimaging, Forschungszentrum Jülich GmbH and RWTH Aachen University, Aachen, Germany
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Fischer DL, Gombash SE, Kemp CJ, Manfredsson FP, Polinski NK, Duffy MF, Sortwell CE. Viral Vector-Based Modeling of Neurodegenerative Disorders: Parkinson's Disease. Methods Mol Biol 2016; 1382:367-82. [PMID: 26611600 DOI: 10.1007/978-1-4939-3271-9_26] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Gene therapy methods are increasingly used to model Parkinson's disease (PD) in animals in an effort to test experimental therapeutics within a more relevant context to disease pathophysiology and neuropathology. We have detailed several criteria that are critical or advantageous to accurately modeling PD in a murine model or in a nonhuman primate. Using these criteria, we then evaluate approaches made to model PD using viral vectors to date, including both adeno-associated viruses and lentiviruses. Lastly, we comment on the consideration of aging as a critical factor for modeling PD.
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Affiliation(s)
- D Luke Fischer
- Department of Translational Science & Molecular Medicine, Michigan State University, 333 Bostwick Ave., NE, Grand Rapids, MI, 49503-2532, USA
- MD/PhD Program, Michigan State University, Grand Rapids, MI, USA
- Neuroscience Graduate Program, Michigan State University, Grand Rapids, MI, USA
| | - Sara E Gombash
- Department of Translational Science & Molecular Medicine, Michigan State University, 333 Bostwick Ave., NE, Grand Rapids, MI, 49503-2532, USA
- Neuroscience Graduate Program, University of Cincinnati, Cincinnati, OH, USA
| | - Christopher J Kemp
- Department of Translational Science & Molecular Medicine, Michigan State University, 333 Bostwick Ave., NE, Grand Rapids, MI, 49503-2532, USA
| | - Fredric P Manfredsson
- Translational Science and Molecular Medicine, Michigan State University, College of Human Science, 333 Bostwick Ave., NE, Grand Rapids, MI, 49503-2532, USA
| | - Nicole K Polinski
- Department of Translational Science & Molecular Medicine, Michigan State University, 333 Bostwick Ave., NE, Grand Rapids, MI, 49503-2532, USA
- Neuroscience Graduate Program, Michigan State University, Grand Rapids, MI, USA
| | - Megan F Duffy
- Department of Translational Science & Molecular Medicine, Michigan State University, 333 Bostwick Ave., NE, Grand Rapids, MI, 49503-2532, USA
- Neuroscience Graduate Program, Michigan State University, Grand Rapids, MI, USA
| | - Caryl E Sortwell
- Department of Translational Science & Molecular Medicine, Michigan State University, 333 Bostwick Ave., NE, Grand Rapids, MI, 49503-2532, USA.
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Ikonomov OC, Sbrissa D, Compton LM, Kumar R, Tisdale EJ, Chen X, Shisheva A. The Protein Complex of Neurodegeneration-related Phosphoinositide Phosphatase Sac3 and ArPIKfyve Binds the Lewy Body-associated Synphilin-1, Preventing Its Aggregation. J Biol Chem 2015; 290:28515-28529. [PMID: 26405034 DOI: 10.1074/jbc.m115.669929] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Indexed: 12/14/2022] Open
Abstract
The 5-phosphoinositide phosphatase Sac3, in which loss-of-function mutations are linked to neurodegenerative disorders, forms a stable cytosolic complex with the scaffolding protein ArPIKfyve. The ArPIKfyve-Sac3 heterodimer interacts with the phosphoinositide 5-kinase PIKfyve in a ubiquitous ternary complex that couples PtdIns(3,5)P2 synthesis with turnover at endosomal membranes, thereby regulating the housekeeping endocytic transport in eukaryotes. Neuron-specific associations of the ArPIKfyve-Sac3 heterodimer, which may shed light on the neuropathological mechanisms triggered by Sac3 dysfunction, are unknown. Here we conducted mass spectrometry analysis for brain-derived interactors of ArPIKfyve-Sac3 and unraveled the α-synuclein-interacting protein Synphilin-1 (Sph1) as a new component of the ArPIKfyve-Sac3 complex. Sph1, a predominantly neuronal protein that facilitates aggregation of α-synuclein, is a major component of Lewy body inclusions in neurodegenerative α-synucleinopathies. Modulations in ArPIKfyve/Sac3 protein levels by RNA silencing or overexpression in several mammalian cell lines, including human neuronal SH-SY5Y or primary mouse cortical neurons, revealed that the ArPIKfyve-Sac3 complex specifically altered the aggregation properties of Sph1-GFP. This effect required an active Sac3 phosphatase and proceeded through mechanisms that involved increased Sph1-GFP partitioning into the cytosol and removal of Sph1-GFP aggregates by basal autophagy but not by the proteasomal system. If uncoupled from ArPIKfyve elevation, overexpressed Sac3 readily aggregated, markedly enhancing the aggregation potential of Sph1-GFP. These data identify a novel role of the ArPIKfyve-Sac3 complex in the mechanisms controlling aggregate formation of Sph1 and suggest that Sac3 protein deficiency or overproduction may facilitate aggregation of aggregation-prone proteins, thereby precipitating the onset of multiple neuronal disorders.
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Affiliation(s)
- Ognian C Ikonomov
- Departments of Physiology, Wayne State School of Medicine, Detroit, Michigan 48201
| | - Diego Sbrissa
- Departments of Physiology, Wayne State School of Medicine, Detroit, Michigan 48201
| | - Lauren M Compton
- Departments of Physiology, Wayne State School of Medicine, Detroit, Michigan 48201
| | - Rita Kumar
- Departments of Physiology, Wayne State School of Medicine, Detroit, Michigan 48201; Departments of Emergency Medicine, Wayne State School of Medicine, Detroit, Michigan 48201
| | - Ellen J Tisdale
- Departments of Pharmacology, Wayne State School of Medicine, Detroit, Michigan 48201
| | - Xuequn Chen
- Departments of Physiology, Wayne State School of Medicine, Detroit, Michigan 48201
| | - Assia Shisheva
- Departments of Physiology, Wayne State School of Medicine, Detroit, Michigan 48201.
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Synphilin-1A is a phosphoprotein phosphatase 1-interacting protein and affects PPP1 sorting to subcellular compartments. J Mol Neurosci 2014; 55:385-95. [PMID: 24902662 DOI: 10.1007/s12031-014-0343-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Accepted: 05/27/2014] [Indexed: 12/24/2022]
Abstract
Lewy bodies (LBs) are synphilin-1 (Sph1)-containing aggregates and histological hallmarks of Parkinson's disease. Therefore, understanding processes which modulate the aggregation of Sph1, or its isoform Sph1A, will contribute to our understanding of LBs formation. Protein phosphorylation promotes aggregation, but protein phosphatases with activity towards Sph1 have not been described. The present study documents the identification of a novel Sph1A/phosphoprotein phosphatase 1 (PPP1) complex and unravels its regulatory effect on Sph1A aggregation. Using yeast co-transformation and overlay blot assay, the interaction between Sph1A and PPP1 was mapped to the Sph1A RVTF motif. Then, Sph1A overexpression in human embryonic kidney 293 cells demonstrated that Sph1A specifically targets endogenous PPP1 isoforms to inclusion bodies and that Sph1A/PPP1 complex disruption enhances inclusion bodies formation. Finally, as Sph1A interacted with PPP1CC2, a PPP1 sperm-specific isoform, Sph1 and Sph1A expression was addressed in male germ cells by qRT-PCR, revealing high expression levels in round spermatids. Together, these observations established Sph1A as a novel PPP1-interacting protein able to affect PPP1 sorting to subcellular compartments and Sph1A/PPP1 complex as a negative modulator of LBs formation. Contrarily, in physiological conditions, Sph1 isoforms are pointed as putative participants in vesicle dynamics with implications in neurotransmission and spermiogenesis.
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Casadei N, Pöhler AM, Tomás-Zapico C, Torres-Peraza J, Schwedhelm I, Witz A, Zamolo I, De Heer R, Spruijt B, Noldus LPJJ, Klucken J, Lucas JJ, Kahle PJ, Krüger R, Riess O, Nuber S. Overexpression of synphilin-1 promotes clearance of soluble and misfolded alpha-synuclein without restoring the motor phenotype in aged A30P transgenic mice. Hum Mol Genet 2013; 23:767-81. [PMID: 24064336 DOI: 10.1093/hmg/ddt467] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Lewy bodies and neurites are the pathological hallmark of Parkinson's disease. These structures are composed of fibrillized and ubiquitinated alpha-synuclein suggesting that impaired protein clearance is an important event in aggregate formation. The A30P mutation is known for its fast oligomerization, but slow fibrillization rate. Despite its toxicity to neurons, mechanisms involved in either clearance or conversion of A30P alpha-synuclein from its soluble state into insoluble fibrils and their effects in vivo are poorly understood. Synphilin-1 is present in Lewy bodies, interacting with alpha-synuclein in vivo and in vitro and promotes its sequestration into aggresomes, which are thought to act as cytoprotective agents facilitating protein degradation. We therefore crossed animals overexpressing A30P alpha-synuclein with synphilin-1 transgenic mice to analyze its impact on aggregation, protein clearance and phenotype progression. We observed that co-expression of synphilin-1 mildly delayed the motor phenotype caused by A30P alpha-synuclein. Additionally, the presence of N- and C-terminal truncated alpha-synuclein species and fibrils were strongly reduced in double-transgenic mice when compared with single-transgenic A30P mice. Insolubility of mutant A30P and formation of aggresomes was still detectable in aged double-transgenic mice, paralleled by an increase of ubiquitinated proteins and high autophagic activity. Hence, this study supports the notion that co-expression of synphilin-1 promotes formation of autophagic-susceptible aggresomes and consecutively the degradation of human A30P alpha-synuclein. Notably, although synphilin-1 overexpression significantly reduced formation of fibrils and astrogliosis in aged animals, a similar phenotype is present in single- and double-transgenic mice suggesting additional neurotoxic processes in disease progression.
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Affiliation(s)
- Nicolas Casadei
- Institute of Medical Genetics and Applied Genomics, University Tübingen, Tübingen, Germany
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Ageta-Ishihara N, Yamakado H, Morita T, Hattori S, Takao K, Miyakawa T, Takahashi R, Kinoshita M. Chronic overload of SEPT4, a parkin substrate that aggregates in Parkinson's disease, causes behavioral alterations but not neurodegeneration in mice. Mol Brain 2013; 6:35. [PMID: 23938054 PMCID: PMC3751304 DOI: 10.1186/1756-6606-6-35] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Accepted: 08/09/2013] [Indexed: 12/13/2022] Open
Abstract
Background In autosomal recessive early-onset Parkinsonism (PARK2), the pathogenetic process from the loss of function of a ubiquitin ligase parkin to the death of dopamine neurons remains unclear. A dominant hypothesis attributes the neurotoxicity to accumulated substrates that are exempt from parkin-mediated degradation. Parkin substrates include two septins; SEPT4/CDCrel-2 which coaggregates with α-synuclein as Lewy bodies in Parkinson’s disease, and its closest homolog SEPT5/CDCrel-1/PNUTL1 whose overload with viral vector can rapidly eliminate dopamine neurons in rats. However, chronic effects of pan-neural overload of septins have never been examined in mammals. To address this, we established a line of transgenic mice that express the largest gene product SEPT454kDa via the prion promoter in the entire brain. Results Histological examination and biochemical quantification of SEPT4-associated proteins including α-synuclein and the dopamine transporter in the nigrostriatal dopamine neurons found no significant difference between Sept4Tg/+ and wild-type littermates. Thus, the hypothetical pathogenicity by the chronic overload of SEPT4 alone, if any, is insufficient to trigger neurodegenerative process in the mouse brain. Intriguingly, however, a systematic battery of behavioral tests revealed unexpected abnormalities in Sept4Tg/+ mice that include consistent attenuation of voluntary activities in distinct behavioral paradigms and altered social behaviors. Conclusions Together, these data indicate that septin dysregulations commonly found in postmortem human brains with Parkinson’s disease, schizophrenia and bipolar disorders may be responsible for a subset of behavioral abnormalities in the patients.
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Affiliation(s)
- Natsumi Ageta-Ishihara
- Department of Molecular Biology, Division of Biological Sciences, Nagoya University Graduate School of Science, Nagoya, Japan
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MacArthur L, Ressom H, Shah S, Federoff HJ. Network modeling to identify new mechanisms and therapeutic targets for Parkinson’s disease. Expert Rev Neurother 2013; 13:685-93. [DOI: 10.1586/ern.13.59] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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10
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Löw K, Aebischer P. Use of viral vectors to create animal models for Parkinson's disease. Neurobiol Dis 2012; 48:189-201. [DOI: 10.1016/j.nbd.2011.12.038] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2011] [Accepted: 12/20/2011] [Indexed: 12/15/2022] Open
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Aggresome formation and segregation of inclusions influence toxicity of α-synuclein and synphilin-1 in yeast. Biochem Soc Trans 2012; 39:1476-81. [PMID: 21936837 DOI: 10.1042/bst0391476] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
PD (Parkinson's disease) is a neurodegenerative disorder, caused by a selective loss of dopaminergic neurons in the substantia nigra, which affects an increasing number of the elderly population worldwide. One of the major hallmarks of PD is the occurrence of intracellular protein deposits in the dying neurons, termed Lewy bodies, which contain different proteins, including aggregated α-synuclein and its interacting protein synphilin-1. During the last decade, a number of groups developed yeast models that reproduced important features of PD and allowed the deciphering of pathways underlying the cytotoxicity triggered by α-synuclein. Here, we review the recent contributions obtained with yeast models designed to study the presumed pathobiology of synphilin-1. These models pointed towards a crucial role of the sirtuin Sir2 and the chaperonin complex TRiC (TCP-1 ring complex)/CCT (chaperonin containing TCP-1) in handling misfolded and aggregated proteins.
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Li X, Tamashiro KLK, Liu Z, Bello NT, Wang X, Aja S, Bi S, Ladenheim EE, Ross CA, Moran TH, Smith WW. A novel obesity model: synphilin-1-induced hyperphagia and obesity in mice. Int J Obes (Lond) 2011; 36:1215-21. [PMID: 22158267 PMCID: PMC3439552 DOI: 10.1038/ijo.2011.235] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Aims The pathogenesis of obesity remains incompletely understood and the exploration of the role of novel proteins in obesity may provide important insights into its causes and treatments. Here we report a previously unidentified role for synphilin-1 in the controls of food intake and body weight. Synphilin-1, a cytoplasmic protein, was initially identified as an interaction partner of alpha-synuclein, and has implications in Parkinson's disease pathogenesis related to protein aggregation. Subjects and methods To study the in vivo role of synphilin-1, we characterized a human synphilin-1 transgenic mouse (SP1) by assessing synphilin-1 expression, plasma parameters, food intake and spontaneous activity to determine the major behavioral changes and their consequences in the development of the obesity phenotype. Results Expression of human synphilin-1 in brain neurons in SP1 mice resulted in increased food intake, body weight and body fat. SP1 mice also displayed hyperinsulinemia, hyperleptinemia and impaired glucose tolerance. Pair-feeding SP1 mice to amounts consumed by non-transgenic mice prevented the increased body weight, adiposity, hyperinsulinemia and hyperleptinemia demonstrating that these were all the consequences of increased food intake. Transgenic expression of synphilin-1 was enriched in hypothalamic nuclei involved in feeding control, and fasting induced elevated endogenous synphilin-1 levels at these sites, suggesting that synphilin-1 is an important player in the hypothalamic energy balance regulatory system. Conclusion These studies identify a novel function of synphilin-1 in controlling food intake and body weight, and may provide a unique obesity model for future studies of obesity pathogenesis and therapeutics.
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Affiliation(s)
- X Li
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD 21201, USA
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Hernández-Vargas R, Fonseca-Ornelas L, López-González I, Riesgo-Escovar J, Zurita M, Reynaud E. Synphilin suppresses α-synuclein neurotoxicity in a Parkinson's disease Drosophila model. Genesis 2011; 49:392-402. [PMID: 21584925 DOI: 10.1002/dvg.20740] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Parkinson's disease (PD) is the second most common neurodegenerative disorder in humans. It affects 1% of the population over 65-years old. Its causes are environmental and genetic. As the world population ages, there is an urgent need for better and more detailed animal models for this kind of disease. In this work we show that the use of transgenic Drosophila is comparable to more complicated and costly animal models such as mice. The Drosophila model behaves very similar to the equivalent transgenic mice model. We show that both Synphilin-1 and α-synuclein are toxic by themselves, but when co-expressed, they suppress their toxicity reciprocally. Importantly, the symptoms induced in the fly can be treated and partially reverted using standard PD pharmacological treatments. This work showcases Drosophila as a detailed and multifaceted model for Parkinson's disease, providing a convenient platform in which to study and find new genetic modifiers of PD. genesis 49:392-402, 2011.
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Affiliation(s)
- René Hernández-Vargas
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, México
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Alvarez-Castelao B, Castaño JG. Synphilin-1 inhibits alpha-synuclein degradation by the proteasome. Cell Mol Life Sci 2011; 68:2643-54. [PMID: 21103907 PMCID: PMC11114841 DOI: 10.1007/s00018-010-0592-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2010] [Revised: 10/13/2010] [Accepted: 11/04/2010] [Indexed: 01/01/2023]
Abstract
Intracellular deposits of aggregated alpha-synuclein are a hallmark of Parkinson's disease. Protein-protein interactions are critical in the regulation of cell proteostasis. Synphilin-1 interacts both in vitro and in vivo with alpha-synuclein promoting its aggregation. We report here that synphilin-1 specifically inhibits the degradation of alpha-synuclein wild-type and its missense mutants by the 20S proteasome due at least in part by the interaction of the ankyrin and coiled-coil domains of synphilin-1 (amino acids 331-555) with the N-terminal region (amino acids 1-60) of alpha-synuclein. Co-expression of synphilin-1 and alpha-synuclein wild-type in HeLa and N2A cells produces a specific increase in the half-life of alpha-synuclein, as degradation of unstable fluorescent reporters is not affected. Synphilin-1 inhibition can be relieved by co-expression of Siah-1 that targets synphilin-1 to degradation. Synphilin-1 inhibition of the proteasomal pathway of degradation of alpha-synuclein may help to understand the pathophysiological changes occurring in PD and other synucleinopathies.
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Affiliation(s)
- Beatriz Alvarez-Castelao
- Departamento de Bioquímica, Instituto de Investigaciones Biomédicas “Alberto Sols”, Universidad Autónoma de Madrid y Consejo Superior de Investigaciones Científicas (UAM-CSIC), Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED) and Idipaz, Facultad de Medicina UAM, 28029 Madrid, Spain
| | - José G. Castaño
- Departamento de Bioquímica, Instituto de Investigaciones Biomédicas “Alberto Sols”, Universidad Autónoma de Madrid y Consejo Superior de Investigaciones Científicas (UAM-CSIC), Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED) and Idipaz, Facultad de Medicina UAM, 28029 Madrid, Spain
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Zhou H, Huang C, Tong J, Hong WC, Liu YJ, Xia XG. Temporal expression of mutant LRRK2 in adult rats impairs dopamine reuptake. Int J Biol Sci 2011; 7:753-61. [PMID: 21698001 PMCID: PMC3119847 DOI: 10.7150/ijbs.7.753] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Accepted: 06/02/2011] [Indexed: 12/17/2022] Open
Abstract
Parkinson's disease (PD) results from progressive degeneration of dopaminergic neurons. Most PD cases are sporadic, but some have pathogenic mutation in the individual genes. Mutation of the leucine-rich repeat kinase-2 (LRRK2) gene is associated with familial and sporadic PD, as exemplified by G2019S substitution. While constitutive expression of mutant LRRK2 in transgenic mice fails to induce neuron death, transient expression of the disease gene by viral delivery causes a substantial loss of dopaminergic neurons in mice. To further assess LRRK2 pathogenesis, we created inducible transgenic rats expressing human LRRK2 with G2019S substitution. Temporal overexpression of LRRK2(G2019S) in adult rats impaired dopamine reuptake by dopamine transporter (DAT) and thus enhanced locomotor activity, the phenotypes that were not observed in transgenic rats constitutively expressing the gene throughout life time. Reduced DAT binding activity is an early sign of dopaminergic dysfunction in asymptomatic subjects carrying pathogenic mutation in LRRK2. Our transgenic rats recapitulated the initiation process of dopaminergic dysfunction caused by pathogenic mutation in LRRK2. Inducible transgenic approach uncovered phenotypes that may be obscured by developmental compensation in constitutive transgenic rats. Finding in inducible LRRK2 transgenic rats would guide developing effective strategy in transgenic studies: Inducible expression of transgene may induce greater phenotypes than constitutive gene expression, particularly in rodents with short life time.
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Affiliation(s)
- Hongxia Zhou
- Department of Pathology, Anatomy & Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA.
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Abstract
Death receptor (DR) signaling has a major impact on the outcome of numerous neurological diseases, including ischemic stroke. DRs mediate not only cell death signals, but also proinflammatory responses and cell proliferation. Identification of regulatory proteins that control the switch between apoptotic and alternative DR signaling opens new therapeutic opportunities. Fas apoptotic inhibitory molecule 2 (Faim2) is an evolutionary conserved, neuron-specific inhibitor of Fas/CD95-mediated apoptosis. To investigate its role during development and in disease models, we generated Faim2-deficient mice. The ubiquitous null mutation displayed a viable and fertile phenotype without overt deficiencies. However, lack of Faim2 caused an increase in susceptibility to combined oxygen-glucose deprivation in primary neurons in vitro as well as in caspase-associated cell death, stroke volume, and neurological impairment after cerebral ischemia in vivo. These processes were rescued by lentiviral Faim2 gene transfer. In summary, we provide evidence that Faim2 is a novel neuroprotective molecule in the context of cerebral ischemia.
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Development of advanced therapies based on viral vector-mediated overexpression of therapeutic molecules and knockdown of disease-related genes for Parkinson’s disease. Ther Deliv 2011; 2:37-50. [DOI: 10.4155/tde.10.95] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The last decade witnessed the translation of several gene-based therapeutic approaches from experimental studies to early clinical trials. Studies targeting the treatment of Parkinson’s disease (PD) were among the forefront of trials in the CNS. In this article, we overview three major strategies for the treatment of PD: the enzyme-replacement strategies are based on well-defined principles of functional restoration and are well suited for treatment of patients with advanced disease who would typically experience complications due to side effects of pharmacotherapy. Neurotrophic factor delivery, on the other hand, aims to delay the disability and eventually modifiy disease progression. Finally, we present an outlook to a completely new way of interfering with the disease process, which is taking advantage of recently discovered RNAi mechanisms in cells. Gene therapy is now becoming a reality in the clinics and developments in the next decade will help uncover the true potential of this approach for not only the treatment of PD patients, but also many other neurological disorders.
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Büttner S, Delay C, Franssens V, Bammens T, Ruli D, Zaunschirm S, de Oliveira RM, Outeiro TF, Madeo F, Buée L, Galas MC, Winderickx J. Synphilin-1 enhances α-synuclein aggregation in yeast and contributes to cellular stress and cell death in a Sir2-dependent manner. PLoS One 2010; 5:e13700. [PMID: 21060871 PMCID: PMC2965147 DOI: 10.1371/journal.pone.0013700] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2010] [Accepted: 10/07/2010] [Indexed: 11/19/2022] Open
Abstract
Background Parkinson's disease is characterized by the presence of cytoplasmic inclusions, known as Lewy bodies, containing both aggregated α-synuclein and its interaction partner, synphilin-1. While synphilin-1 is known to accelerate inclusion formation by α-synuclein in mammalian cells, its effect on cytotoxicity remains elusive. Methodology/Principal Findings We expressed wild-type synphilin-1 or its R621C mutant either alone or in combination with α-synuclein in the yeast Saccharomyces cerevisiae and monitored the intracellular localization and inclusion formation of the proteins as well as the repercussions on growth, oxidative stress and cell death. We found that wild-type and mutant synphilin-1 formed inclusions and accelerated inclusion formation by α-synuclein in yeast cells, the latter being correlated to enhanced phosphorylation of serine-129. Synphilin-1 inclusions co-localized with lipid droplets and endomembranes. Consistently, we found that wild-type and mutant synphilin-1 interacts with detergent-resistant membrane domains, known as lipid rafts. The expression of synphilin-1 did not incite a marked growth defect in exponential cultures, which is likely due to the formation of aggresomes and the retrograde transport of inclusions from the daughter cells back to the mother cells. However, when the cultures approached stationary phase and during subsequent ageing of the yeast cells, both wild-type and mutant synphilin-1 reduced survival and triggered apoptotic and necrotic cell death, albeit to a different extent. Most interestingly, synphilin-1 did not trigger cytotoxicity in ageing cells lacking the sirtuin Sir2. This indicates that the expression of synphilin-1 in wild-type cells causes the deregulation of Sir2-dependent processes, such as the maintenance of the autophagic flux in response to nutrient starvation. Conclusions/Significance Our findings demonstrate that wild-type and mutant synphilin-1 are lipid raft interacting proteins that form inclusions and accelerate inclusion formation of α-synuclein when expressed in yeast. Synphilin-1 thereby induces cytotoxicity, an effect most pronounced for the wild-type protein and mediated via Sir2-dependent processes.
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Affiliation(s)
- Sabrina Büttner
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Charlotte Delay
- Functional Biology, Katholieke Universiteit Leuven, Heverlee, Belgium
- Alzheimer & Tauopathies, Inserm U837, Lille, France
- Jean-Pierre Aubert Research Centre, Université Lille Nord de France, Lille, France
- Faculté de Médecine-Pole Recherche, Université du Droit et de la Santé de Lille, Lille, France
- Centre Hospitalier Universitaire, Lille, France
| | - Vanessa Franssens
- Functional Biology, Katholieke Universiteit Leuven, Heverlee, Belgium
| | - Tine Bammens
- Functional Biology, Katholieke Universiteit Leuven, Heverlee, Belgium
| | - Doris Ruli
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Sandra Zaunschirm
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Rita Machado de Oliveira
- Cell and Molecular Neuroscience Unit, Instituto de Medicina Molecular, Lisboa, Portugal
- Instituto de Fisiologia, Universidade de Lisboa, Lisboa, Portugal
| | - Tiago Fleming Outeiro
- Cell and Molecular Neuroscience Unit, Instituto de Medicina Molecular, Lisboa, Portugal
- Instituto de Fisiologia, Universidade de Lisboa, Lisboa, Portugal
| | - Frank Madeo
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Luc Buée
- Alzheimer & Tauopathies, Inserm U837, Lille, France
- Jean-Pierre Aubert Research Centre, Université Lille Nord de France, Lille, France
- Faculté de Médecine-Pole Recherche, Université du Droit et de la Santé de Lille, Lille, France
- Centre Hospitalier Universitaire, Lille, France
| | - Marie-Christine Galas
- Alzheimer & Tauopathies, Inserm U837, Lille, France
- Jean-Pierre Aubert Research Centre, Université Lille Nord de France, Lille, France
- Faculté de Médecine-Pole Recherche, Université du Droit et de la Santé de Lille, Lille, France
- Centre Hospitalier Universitaire, Lille, France
| | - Joris Winderickx
- Functional Biology, Katholieke Universiteit Leuven, Heverlee, Belgium
- * E-mail:
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Falkenburger BH, Jensen JB, Hille B. Kinetics of M1 muscarinic receptor and G protein signaling to phospholipase C in living cells. ACTA ACUST UNITED AC 2010; 135:81-97. [PMID: 20100890 PMCID: PMC2812500 DOI: 10.1085/jgp.200910344] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
G protein-coupled receptors (GPCRs) mediate responses to external stimuli in various cell types. Early events, such as the binding of ligand and G proteins to the receptor, nucleotide exchange (NX), and GTPase activity at the Galpha subunit, are common for many different GPCRs. For G(q)-coupled M(1) muscarinic (acetylcholine) receptors (M(1)Rs), we recently measured time courses of intermediate steps in the signaling cascade using Förster resonance energy transfer (FRET). The expression of FRET probes changes the density of signaling molecules. To provide a full quantitative description of M(1)R signaling that includes a simulation of kinetics in native (tsA201) cells, we now determine the density of FRET probes and construct a kinetic model of M(1)R signaling through G(q) to activation of phospholipase C (PLC). Downstream effects on the trace membrane lipid phosphatidylinositol 4,5-bisphosphate (PIP(2)) and PIP(2)-dependent KCNQ2/3 current are considered in our companion paper in this issue (Falkenburger et al. 2010. J. Gen. Physiol. doi:10.1085/jgp.200910345). By calibrating their fluorescence intensity, we found that we selected transfected cells for our experiments with approximately 3,000 fluorescently labeled receptors, G proteins, or PLC molecules per microm(2) of plasma membrane. Endogenous levels are much lower, 1-40 per microm(2). Our kinetic model reproduces the time courses and concentration-response relationships measured by FRET and explains observed delays. It predicts affinities and rate constants that align well with literature values. In native tsA201 cells, much of the delay between ligand binding and PLC activation reflects slow binding of G proteins to receptors. With M(1)R and Gbeta FRET probes overexpressed, 10% of receptors have G proteins bound at rest, rising to 73% in the presence of agonist. In agreement with previous work, the model suggests that binding of PLC to Galpha(q) greatly speeds up NX and GTPase activity, and that PLC is maintained in the active state by cycles of rapid GTP hydrolysis and NX on Galpha(q) subunits bound to PLC.
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Affiliation(s)
- Björn H Falkenburger
- Department of Physiology and Biophysics, University of Washington, Seattle, WA 98195, USA
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Transgenic overexpression of the alpha-synuclein interacting protein synphilin-1 leads to behavioral and neuropathological alterations in mice. Neurogenetics 2010; 11:107-20. [PMID: 19760259 DOI: 10.1007/s10048-009-0212-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2009] [Accepted: 08/03/2009] [Indexed: 12/11/2022]
Abstract
Synphilin-1 has been identified as an interacting protein of alpha-synuclein, Parkin, and LRRK2, proteins which are mutated in familial forms of Parkinson disease (PD). Subsequently, synphilin-1 has also been shown to be an intrinsic component of Lewy bodies in sporadic PD. In order to elucidate the role of synphilin-1 in the pathogenesis of PD, we generated transgenic mice overexpressing wild-type and mutant (R621C) synphilin-1 driven by a mouse prion protein promoter. Transgenic expression of both wild-type and the R621C variant synphilin-1 resulted in increased dopamine levels of the nigrostriatal system in 3-month-old mice. Furthermore, we found pathological ubiquitin-positive inclusions in cerebellar sections and dark-cell degeneration of Purkinje cells. Both transgenic mouse lines showed significant reduction of motor skill learning and motor performance. These findings suggest a pathological role of overexpressed synphilin-1 in vivo and will help to further elucidate the mechanisms of protein aggregation and neuronal cell death.
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Smith WW, Liu Z, Liang Y, Masuda N, Swing DA, Jenkins NA, Copeland NG, Troncoso JC, Pletnikov M, Dawson TM, Martin LJ, Moran TH, Lee MK, Borchelt DR, Ross CA. Synphilin-1 attenuates neuronal degeneration in the A53T alpha-synuclein transgenic mouse model. Hum Mol Genet 2010; 19:2087-98. [PMID: 20185556 DOI: 10.1093/hmg/ddq086] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Genetic alterations in alpha-synuclein cause autosomal dominant familial Parkinsonism and may contribute to sporadic Parkinson's disease (PD). Synphilin-1 is an alpha-synuclein-interacting protein, with implications in PD pathogenesis related to protein aggregation. Currently, the in vivo role of synphilin-1 in alpha-synuclein-linked pathogenesis is not fully understood. Using the mouse prion protein promoter, we generated synphilin-1 transgenic mice, which did not display PD-like phenotypes. However, synphilin-1/A53T alpha-synuclein double-transgenic mice survived longer than A53T alpha-synuclein single-transgenic mice. There were attenuated A53T alpha-synuclein-induced motor abnormalities and decreased astroglial reaction and neuronal degeneration in brains in double-transgenic mice. Overexpression of synphilin-1 decreased caspase-3 activation, increased beclin-1 and LC3 II expression and promoted formation of aggresome-like structures, suggesting that synphilin-1 alters multiple cellular pathways to protect against neuronal degeneration. These studies demonstrate that synphilin-1 can diminish the severity of alpha-synucleinopathy and play a neuroprotective role against A53T alpha-synuclein toxicity in vivo.
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Affiliation(s)
- Wanli W Smith
- Division of Neurobiology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
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Xie YY, Zhou CJ, Zhou ZR, Hong J, Che MX, Fu QS, Song AX, Lin DH, Hu HY. Interaction with synphilin-1 promotes inclusion formation of alpha-synuclein: mechanistic insights and pathological implication. FASEB J 2009; 24:196-205. [PMID: 19762560 DOI: 10.1096/fj.09-133082] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
alpha-Synuclein (alpha-Syn) is the major component of Lewy bodies (LBs) deposited in the brains of patients with Parkinson's disease. Synphilin-1 (Sph1) is a novel alpha-Syn-interacting protein also present in the LBs. However, the roles of alpha-Syn-Sph1 interaction in LB formation and in the related pathogenesis are still unclear. We have studied the interaction between alpha-Syn and Sph1 by biochemical and structural approaches and found that the central coiled-coil domain of Sph1 specifically interacts with the N-terminal stretch of alpha-Syn. When overexpressed in HEK 293T cells, Sph1 forms inclusions together with alpha-Syn, but the Sph1-positive inclusions cannot recruit the N-terminally truncated alpha-Syn. The central portion of Sph1 can also recruit alpha-Syn and induce inclusion formation through its coiled-coil domain. These observations demonstrate that the alpha-Syn-Sph1 interaction significantly promotes the formation of cytoplasmic alpha-Syn inclusions, which may have implications for LB formation in neural cells. We have also elucidated solution structure of the coiled-coil domain of Sph1 and its interaction with the N-terminal peptide of alpha-Syn. The specific interaction between alpha-Syn and Sph1 provides mechanistic insights into the inclusion-body formation in cells and pathological implication in Parkinson's disease.
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Affiliation(s)
- Yuan-Yuan Xie
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai, China
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Versatile somatic gene transfer for modeling neurodegenerative diseases. Neurotox Res 2009; 16:329-42. [PMID: 19669852 DOI: 10.1007/s12640-009-9080-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2009] [Revised: 03/26/2009] [Accepted: 06/29/2009] [Indexed: 12/20/2022]
Abstract
A growing variety of technical approaches allow control over the expression of selected genes in living organisms. The ability to deliver functional exogenous genes involved in neurodegenerative diseases has opened pathological processes to experimental analysis and targeted therapeutic development in rodent and primate preclinical models. Biological adaptability, economic animal use, and reduced model development costs complement improved control over spatial and temporal gene expression compared with conventional transgenic models. A review of viral vector studies, typically adeno-associated virus or lentivirus, for expression of three proteins that are central to major neurodegenerative diseases, will illustrate how this approach has powered new advances and opportunities in CNS disease research.
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