1
|
Daskivich GJ, Brodsky JL. The generation of detergent-insoluble clipped fragments from an ERAD substrate in mammalian cells. Sci Rep 2023; 13:21508. [PMID: 38057493 PMCID: PMC10700608 DOI: 10.1038/s41598-023-48769-z] [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: 07/28/2023] [Accepted: 11/30/2023] [Indexed: 12/08/2023] Open
Abstract
Proteostasis ensures the proper synthesis, folding, and trafficking of proteins and is required for cellular and organellar homeostasis. This network also oversees protein quality control within the cell and prevents accumulation of aberrant proteins, which can lead to cellular dysfunction and disease. For example, protein aggregates irreversibly disrupt proteostasis and can exert gain-of-function toxic effects. Although this process has been examined in detail for cytosolic proteins, how endoplasmic reticulum (ER)-tethered, aggregation-prone proteins are handled is ill-defined. To determine how a membrane protein with a cytoplasmic aggregation-prone domain is routed for ER-associated degradation (ERAD), we analyzed a new model substrate, TM-Ubc9ts. In yeast, we previously showed that TM-Ubc9ts ERAD requires Hsp104, which is absent in higher cells. In transient and stable HEK293 cells, we now report that TM-Ubc9ts degradation is largely proteasome-dependent, especially at elevated temperatures. In contrast to yeast, clipped TM-Ubc9ts polypeptides, which are stabilized upon proteasome inhibition, accumulate and are insoluble at elevated temperatures. TM-Ubc9ts cleavage is independent of the intramembrane protease RHBDL4, which clips other classes of ERAD substrates. These studies highlight an unappreciated mechanism underlying the degradation of aggregation-prone substrates in the ER and invite further work on other proteases that contribute to ERAD.
Collapse
Affiliation(s)
- Grant J Daskivich
- A320 Langley Hall, Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - Jeffrey L Brodsky
- A320 Langley Hall, Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15260, USA.
| |
Collapse
|
2
|
Pomatto LCD, Sisliyan C, Wong S, Cline M, Tower J, Davies KJA. The proteasome beta 5 subunit is essential for sexually divergent adaptive homeostatic responses to oxidative stress in D. melanogaster. Free Radic Biol Med 2020; 160:67-77. [PMID: 32758664 PMCID: PMC7704559 DOI: 10.1016/j.freeradbiomed.2020.07.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 07/01/2020] [Accepted: 07/02/2020] [Indexed: 11/17/2022]
Abstract
Our studies center on the physiological phenomenon of adaptive homeostasis in which very low, signaling levels of an oxidant can induce transient expansion of the baseline homeostatic range of protective mechanisms, resulting in transient stress protection. The 20S proteasome is a major element of such inducible defense enzymes against oxidative stress but the relative importance of each of its three proteolytic subunits, β1, β2, and β5, is only poorly understood. We focused the present studies on determining the role of the β5 subunit in adaptation, survival, and lifespan. Decreased expression of the 20S proteasome β5 subunit (with RNAi) blocked the adaptive increase in the catalytic activities of the 20S proteasome response to signaling levels of H2O2 in female flies. Similarly, female-specific adaptive increases in survival following H2O2 pretreatment and subsequent toxic challenge was blocked. In contrast, direct overexpression of the 20S proteasome β5 subunit enabled an increased 20S proteasome proteolytic response, but prevented further adaptive homeostatic increases through H2O2 signaling, indicating there is a maximum 'ceiling' to the adaptive response. Males showed no adaptive change in proteasomal levels or activity whatsoever with H2O2 pretreatment and exhibited no significant impact upon the other 2 proteolytic subunits of the proteasome. However, chronic loss of the β5 subunit led to shortened lifespan in both sexes. Our exploration of the importance of the 20S proteasome β5 subunit in adaptive homeostasis highlights the interconnection between signal transduction pathways and regulated gene expression in sexually divergent responses to oxidative stimulation.
Collapse
Affiliation(s)
- Laura C D Pomatto
- Leonard Davis School of Gerontology of the Ethel Percy Andrus Gerontology Center, The University of Southern California, Los Angeles, CA, 00089-0191, USA; National Institute of General Medical Sciences, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Christina Sisliyan
- Leonard Davis School of Gerontology of the Ethel Percy Andrus Gerontology Center, The University of Southern California, Los Angeles, CA, 00089-0191, USA
| | - Sarah Wong
- Leonard Davis School of Gerontology of the Ethel Percy Andrus Gerontology Center, The University of Southern California, Los Angeles, CA, 00089-0191, USA
| | - Mayme Cline
- Leonard Davis School of Gerontology of the Ethel Percy Andrus Gerontology Center, The University of Southern California, Los Angeles, CA, 00089-0191, USA
| | - John Tower
- Leonard Davis School of Gerontology of the Ethel Percy Andrus Gerontology Center, The University of Southern California, Los Angeles, CA, 00089-0191, USA; Molecular & Computational Biology Program of the Department of Biological Sciences, Dornsife College of Letters, Arts, and Sciences, The University of Southern California, Los Angeles, CA, 90089-0191, USA
| | - Kelvin J A Davies
- Leonard Davis School of Gerontology of the Ethel Percy Andrus Gerontology Center, The University of Southern California, Los Angeles, CA, 00089-0191, USA; Molecular & Computational Biology Program of the Department of Biological Sciences, Dornsife College of Letters, Arts, and Sciences, The University of Southern California, Los Angeles, CA, 90089-0191, USA; Department of Biochemistry & Molecular Medicine, Keck School of Medicine of USC, The University of Southern California, Los Angeles, CA, USA.
| |
Collapse
|
3
|
Wang Z, Gao G, Duan C, Yang H. Progress of immunotherapy of anti-α-synuclein in Parkinson's disease. Biomed Pharmacother 2019; 115:108843. [PMID: 31055236 DOI: 10.1016/j.biopha.2019.108843] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 03/14/2019] [Accepted: 03/31/2019] [Indexed: 12/12/2022] Open
Abstract
Many neurodegenerative diseases are characterized by progressive loss of neurons and abnormal protein accumulation, including amyloid (A)β and tau in Alzheimer's disease and Lewy bodies and α-synuclein (α-syn) in Parkinson's disease (PD). Recent evidence suggests that adaptive immunity plays an important role in PD, and that anti-α-syn antibodies can be used as therapy in neurodegenerative diseases; monoclonal antibodies were shown to inhibit α-syn propagation and aggregation in PD models and patients. In this review, we summarize the different pathological states of α-syn, including gene mutations, truncation, phosphorylation, and the high molecular weight form, and describe the specific antibodies that recognize the α-syn monomer or oligomer, some of which have been tested in clinic trials. We also discuss future research directions and potential targets in PD therapy.
Collapse
Affiliation(s)
- Zhipeng Wang
- Department of Neurobiology School of Basic Medical Sciences, Center of Parkinson Disease Beijing Institute for Brain Disorders, Beijing Key Laboratory for Neural Regeneration and Repair, Beijing Key Laboratory on Parkinson's Disease, Key Laboratory for Neurodegenerative Disease of the Ministry of Education, Capital Medical University, Beijing, 100069, China
| | - Ge Gao
- Department of Neurobiology School of Basic Medical Sciences, Center of Parkinson Disease Beijing Institute for Brain Disorders, Beijing Key Laboratory for Neural Regeneration and Repair, Beijing Key Laboratory on Parkinson's Disease, Key Laboratory for Neurodegenerative Disease of the Ministry of Education, Capital Medical University, Beijing, 100069, China
| | - Chunli Duan
- Department of Neurobiology School of Basic Medical Sciences, Center of Parkinson Disease Beijing Institute for Brain Disorders, Beijing Key Laboratory for Neural Regeneration and Repair, Beijing Key Laboratory on Parkinson's Disease, Key Laboratory for Neurodegenerative Disease of the Ministry of Education, Capital Medical University, Beijing, 100069, China
| | - Hui Yang
- Department of Neurobiology School of Basic Medical Sciences, Center of Parkinson Disease Beijing Institute for Brain Disorders, Beijing Key Laboratory for Neural Regeneration and Repair, Beijing Key Laboratory on Parkinson's Disease, Key Laboratory for Neurodegenerative Disease of the Ministry of Education, Capital Medical University, Beijing, 100069, China.
| |
Collapse
|
4
|
Bengoa-Vergniory N, Roberts RF, Wade-Martins R, Alegre-Abarrategui J. Alpha-synuclein oligomers: a new hope. Acta Neuropathol 2017; 134:819-838. [PMID: 28803412 PMCID: PMC5663814 DOI: 10.1007/s00401-017-1755-1] [Citation(s) in RCA: 250] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 07/21/2017] [Accepted: 07/22/2017] [Indexed: 01/22/2023]
Abstract
Alpha-synuclein is a protein implicated in Parkinson’s disease and thought to be one of the main pathological drivers in the disease, although it remains unclear how this protein elicits its neurotoxic effects. Recent findings indicate that the assembly of toxic oligomeric species of alpha-synuclein may be one of the key processes for the pathology and spread of the disease. The absence of a sensitive in situ detection method has hindered the study of these oligomeric species and the role they play in the human brain until recently. In this review, we assess the evidence for the toxicity and prion-like activity of oligomeric forms of alpha-synuclein and discuss the advances in our understanding of the role of alpha-synuclein in Parkinson’s disease that may be brought about by the specific and sensitive detection of distinct oligomeric species in post-mortem patient brain. Finally, we discuss current approaches being taken to therapeutically target alpha-synuclein oligomers and their implications.
Collapse
Affiliation(s)
- Nora Bengoa-Vergniory
- Department of Physiology, Anatomy and Genetics, Oxford Parkinson's Disease Centre, University of Oxford, South Parks Road, Oxford, OX1 3QT, UK
| | - Rosalind F Roberts
- Montreal Neurological Institute, McGill University, 3801 Rue University, Montreal, QC, H3A 2B4, Canada
| | - Richard Wade-Martins
- Department of Physiology, Anatomy and Genetics, Oxford Parkinson's Disease Centre, University of Oxford, South Parks Road, Oxford, OX1 3QT, UK.
| | - Javier Alegre-Abarrategui
- Department of Physiology, Anatomy and Genetics, Oxford Parkinson's Disease Centre, University of Oxford, South Parks Road, Oxford, OX1 3QT, UK.
| |
Collapse
|
5
|
Rey NL, George S, Brundin P. Review: Spreading the word: precise animal models and validated methods are vital when evaluating prion-like behaviour of alpha-synuclein. Neuropathol Appl Neurobiol 2016; 42:51-76. [PMID: 26666838 DOI: 10.1111/nan.12299] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 12/08/2015] [Accepted: 12/15/2015] [Indexed: 01/02/2023]
Abstract
Synucleinopathies are characterized by abnormal proteinaceous aggregates, mainly composed of fibrillar α-synuclein (α-syn). It is now believed that α-syn can form small aggregates in a restricted number of cells, that propagate to neighbouring cells and seed aggregation of endogenous α-syn, in a 'prion-like manner'. This process could underlie the stereotypical progression of Lewy bodies described by Braak and colleagues across different stages of Parkinson's disease (PD). This prion-like behaviour of α-syn has been recently investigated in animal models of PD or multiple system atrophy (MSA). These models investigate the cell-to-cell transfer of α-syn seeds, or the induction and spreading of α-syn pathology in transgenic or wild-type rodent brain. In this review, we first outline the involvement of α-syn in Lewy body diseases and MSA, and discuss how 'prion-like' mechanisms can contribute to disease. Thereon, we debate the relevance of animal models used to study prion-like propagation. Finally, we review current main histological methods used to assess α-syn pathology both in animal models and in human samples and their relevance to the disease. Specifically, we discuss using α-syn phosphorylated at serine 129 as a marker of pathology, and the novel methods available that allow for more sensitive detection of early pathology, which has relevance for modelling synucleinopathies.
Collapse
Affiliation(s)
- N L Rey
- Van Andel Research Institute, Center for Neurodegenerative Science, Grand Rapids, Michigan, USA
| | - S George
- Van Andel Research Institute, Center for Neurodegenerative Science, Grand Rapids, Michigan, USA
| | - P Brundin
- Van Andel Research Institute, Center for Neurodegenerative Science, Grand Rapids, Michigan, USA
| |
Collapse
|
6
|
Caspase-1 causes truncation and aggregation of the Parkinson's disease-associated protein α-synuclein. Proc Natl Acad Sci U S A 2016; 113:9587-92. [PMID: 27482083 DOI: 10.1073/pnas.1610099113] [Citation(s) in RCA: 204] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The aggregation of α-synuclein (aSyn) leading to the formation of Lewy bodies is the defining pathological hallmark of Parkinson's disease (PD). Rare familial PD-associated mutations in aSyn render it aggregation-prone; however, PD patients carrying wild type (WT) aSyn also have aggregated aSyn in Lewy bodies. The mechanisms by which WT aSyn aggregates are unclear. Here, we report that inflammation can play a role in causing the aggregation of WT aSyn. We show that activation of the inflammasome with known stimuli results in the aggregation of aSyn in a neuronal cell model of PD. The insoluble aggregates are enriched with truncated aSyn as found in Lewy bodies of the PD brain. Inhibition of the inflammasome enzyme caspase-1 by chemical inhibition or genetic knockdown with shRNA abated aSyn truncation. In vitro characterization confirmed that caspase-1 directly cleaves aSyn, generating a highly aggregation-prone species. The truncation-induced aggregation of aSyn is toxic to neuronal culture, and inhibition of caspase-1 by shRNA or a specific chemical inhibitor improved the survival of a neuronal PD cell model. This study provides a molecular link for the role of inflammation in aSyn aggregation, and perhaps in the pathogenesis of sporadic PD as well.
Collapse
|
7
|
Szczepankiewicz O, Linse B, Meisl G, Thulin E, Frohm B, Frigerio CS, Colvin MT, Jacavone AC, Griffin RG, Knowles T, Walsh DM, Linse S. N-Terminal Extensions Retard Aβ42 Fibril Formation but Allow Cross-Seeding and Coaggregation with Aβ42. J Am Chem Soc 2015; 137:14673-85. [PMID: 26535489 PMCID: PMC5412961 DOI: 10.1021/jacs.5b07849] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Amyloid β-protein (Aβ) sequence length variants with varying aggregation propensity coexist in vivo, where coaggregation and cross-catalysis phenomena may affect the aggregation process. Until recently, naturally occurring amyloid β-protein (Aβ) variants were believed to begin at or after the canonical β-secretase cleavage site within the amyloid β-protein precursor. However, N-terminally extended forms of Aβ (NTE-Aβ) were recently discovered and may contribute to Alzheimer's disease. Here, we have used thioflavin T fluorescence to study the aggregation kinetics of Aβ42 variants with N-terminal extensions of 5-40 residues, and transmission electron microscopy to analyze the end states. We find that all variants form amyloid fibrils of similar morphology as Aβ42, but the half-time of aggregation (t1/2) increases exponentially with extension length. Monte Carlo simulations of model peptides suggest that the retardation is due to an underlying general physicochemical effect involving reduced frequency of productive molecular encounters. Indeed, global kinetic analyses reveal that NTE-Aβ42s form fibrils via the same mechanism as Aβ42, but all microscopic rate constants (primary and secondary nucleation, elongation) are reduced for the N-terminally extended variants. Still, Aβ42 and NTE-Aβ42 coaggregate to form mixed fibrils and fibrils of either Aβ42 or NTE-Aβ42 catalyze aggregation of all monomers. NTE-Aβ42 monomers display reduced aggregation rate with all kinds of seeds implying that extended termini interfere with the ability of monomers to nucleate or elongate. Cross-seeding or coaggregation may therefore represent an important contribution in the in vivo formation of assemblies believed to be important in disease.
Collapse
Affiliation(s)
- Olga Szczepankiewicz
- Department of Biochemistry and Structural Biology, Lund University, P O Box 124, 221 00 Lund, Sweden
| | - Björn Linse
- Department of Biochemistry and Structural Biology, Lund University, P O Box 124, 221 00 Lund, Sweden
| | - Georg Meisl
- Department of Chemistry, Cambridge University, Lensfield Road, Cambridge, CB2 1EW, United Kingdom
| | - Eva Thulin
- Department of Biochemistry and Structural Biology, Lund University, P O Box 124, 221 00 Lund, Sweden
| | - Birgitta Frohm
- Department of Biochemistry and Structural Biology, Lund University, P O Box 124, 221 00 Lund, Sweden
| | - Carlo Sala Frigerio
- Laboratory for Neurodegenerative Research, Conway Institute of Biomedical and Biomolecular Research, University College Dublin, Belfield, Dublin 4, Republic of Ireland
| | - Michael T. Colvin
- Department of Chemistry and Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Angela C. Jacavone
- Department of Chemistry and Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Robert G. Griffin
- Department of Chemistry and Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Tuomas Knowles
- Department of Chemistry, Cambridge University, Lensfield Road, Cambridge, CB2 1EW, United Kingdom
| | - Dominic M. Walsh
- Laboratory for Neurodegenerative Research, Conway Institute of Biomedical and Biomolecular Research, University College Dublin, Belfield, Dublin 4, Republic of Ireland
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Sara Linse
- Department of Biochemistry and Structural Biology, Lund University, P O Box 124, 221 00 Lund, Sweden
| |
Collapse
|
8
|
Sengupta U, Guerrero-Muñoz MJ, Castillo-Carranza DL, Lasagna-Reeves CA, Gerson JE, Paulucci-Holthauzen AA, Krishnamurthy S, Farhed M, Jackson GR, Kayed R. Pathological interface between oligomeric alpha-synuclein and tau in synucleinopathies. Biol Psychiatry 2015; 78:672-83. [PMID: 25676491 DOI: 10.1016/j.biopsych.2014.12.019] [Citation(s) in RCA: 125] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 12/05/2014] [Accepted: 12/11/2014] [Indexed: 10/24/2022]
Abstract
BACKGROUND Aberrant accumulation of α-synuclein constitutes inclusion bodies that are considered a characteristic feature of a group of neurological disorders described as synucleinopathies. Often, multiple disease-causing proteins overlap within a given disease pathology. An emerging body of research focuses on the oligomeric populations of various pathogenic proteins, considering them as the culprits causing neuronal damage and degeneration. To this end, the use of conformation-specific antibodies has proven to be an effective tool. Previous work from our laboratory and others has shown that oligomeric entities of α-synuclein and tau accumulate in their respective diseases, but their interrelationship at this higher order has yet to be shown in synucleinopathies. METHODS Here, we used two novel conformation-specific antibodies, F8H7 and Syn33, which recognize α-synuclein oligomers and were developed in our laboratory. We investigated brain tissue from five of each Parkinson's disease and dementia with Lewy bodies patients by performing biophysical and biochemical assays using these antibodies, in addition to the previously characterized anti-tau oligomer antibody T22. RESULTS We demonstrate that in addition to the deposition of oligomeric α-synuclein, tau oligomers accumulate in these diseased brains compared with control brains. Moreover, we observed that oligomers of tau and α-synuclein exist in the same aggregates, forming hybrid oligomers in these patients' brains. CONCLUSIONS In addition to the deposition of tau oligomers, our results also provide compelling evidence of co-occurrence of α-synuclein and tau into their most toxic forms, i.e., oligomers suggesting that these species interact and influence each other's aggregation via an interface in synucleinopathies.
Collapse
Affiliation(s)
- Urmi Sengupta
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, Texas; Departments of Neurology and Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas
| | - Marcos J Guerrero-Muñoz
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, Texas; Departments of Neurology and Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas
| | - Diana L Castillo-Carranza
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, Texas; Departments of Neurology and Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas
| | - Cristian A Lasagna-Reeves
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, Texas; Departments of Neurology and Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas
| | - Julia E Gerson
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, Texas; Departments of Neurology and Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas
| | | | - Shashirekha Krishnamurthy
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, Texas; Departments of Neurology and Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas
| | - Malika Farhed
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, Texas; Departments of Neurology and Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas
| | - George R Jackson
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, Texas; Departments of Neurology and Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas; Sealy Center for Vaccine Development, University of Texas Medical Branch, Galveston, Texas
| | - Rakez Kayed
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, Texas; Departments of Neurology and Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas; Sealy Center for Vaccine Development, University of Texas Medical Branch, Galveston, Texas.
| |
Collapse
|
9
|
Allen Reish HE, Standaert DG. Role of α-synuclein in inducing innate and adaptive immunity in Parkinson disease. JOURNAL OF PARKINSON'S DISEASE 2015; 5:1-19. [PMID: 25588354 PMCID: PMC4405142 DOI: 10.3233/jpd-140491] [Citation(s) in RCA: 172] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Alpha-synuclein (α-syn) is central to the pathogenesis of Parkinson disease (PD). Gene duplications, triplications and point mutations in SNCA1, the gene encoding α-syn, cause autosomal dominant forms of PD. Aggregated and post-translationally modified forms of α-syn are present in Lewy bodies and Lewy neurites in both sporadic and familial PD, and recent work has emphasized the prion-like ability of aggregated α-syn to produce spreading pathology. Accumulation of abnormal forms of α-syn is a trigger for PD, but recent evidence suggests that much of the downstream neurodegeneration may result from inflammatory responses. Components of both the innate and adaptive immune systems are activated in PD, and influencing interactions between innate and adaptive immune components has been shown to modify the pathological process in animal models of PD. Understanding the relationship between α-syn and subsequent inflammation may reveal novel targets for neuroprotective interventions. In this review, we examine the role of α-syn and modified forms of this protein in the initiation of innate and adaptive immune responses.
Collapse
Affiliation(s)
- Heather E Allen Reish
- Center for Neurodegeneration and Experimental Therapeutics, Department of Neurology, University of Alabama at Birmingham, Alabama, USA
| | - David G Standaert
- Center for Neurodegeneration and Experimental Therapeutics, Department of Neurology, University of Alabama at Birmingham, Alabama, USA
| |
Collapse
|
10
|
Fournier M, Roux A, Garrigue J, Muriel MP, Blanche P, Lashuel HA, Anderson JP, Barbour R, Huang J, du Montcel ST, Brice A, Corti O. Parkin depletion delays motor decline dose-dependently without overtly affecting neuropathology in α-synuclein transgenic mice. BMC Neurosci 2013; 14:135. [PMID: 24192137 PMCID: PMC4228309 DOI: 10.1186/1471-2202-14-135] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Accepted: 10/28/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Mutations of the gene encoding the major component of Lewy bodies (LB), α-synuclein (α-syn), cause autosomal dominant forms of Parkinson's disease (PD), whereas loss-of-function mutations of the gene encoding the multifunctional E3 ubiquitin-protein ligase Parkin account for autosomal recessive forms of the disease. Parkin overproduction protects against α-syn-dependent neurodegeneration in various in vitro and in vivo models, but it remains unclear whether this process is affected by Parkin deficiency. We addressed this issue, by carrying out more detailed analyses of transgenic mice overproducing the A30P variant of human α-syn (hA30Pα-syn) and with two, one or no parkin knockout alleles. RESULTS Longitudinal behavioral follow-up of these mice indicated that Parkin depletion delayed disease-predictive sensorimotor impairment due to α-syn accumulation, in a dose-dependent fashion. At the end stage of the disease, neuronal deposits containing fibrillar α-syn species phosphorylated at S129 (PS129α-syn) were the predominant neuropathological feature in hA30Pα-syn mice, regardless of their parkin expression. Some of these deposits colocalized with the LB markers ubiquitin and α-syn truncated at D135 (α-synD135), indicating that PS129α-syn is subjected to secondary posttranslational modification (PTM); these features were not significantly affected by parkin dysfunction. CONCLUSIONS These findings suggest that Parkin deficiency acts as a protective modifier in α-syn-dependent neurodegeneration, without overtly affecting the composition and characteristics of α-syn deposits in end-stage disease.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | - Olga Corti
- Inserm, U 975, CRICM, Hôpital de la Pitié-Salpêtrière, F-75013 Paris, France.
| |
Collapse
|
11
|
George S, Rey NL, Reichenbach N, Steiner JA, Brundin P. α-Synuclein: the long distance runner. Brain Pathol 2013; 23:350-7. [PMID: 23587141 PMCID: PMC3674536 DOI: 10.1111/bpa.12046] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Accepted: 02/04/2013] [Indexed: 01/11/2023] Open
Abstract
Parkinson's disease is characterized by α-synuclein pathology in the form of Lewy bodies and Lewy neurites. Braak et al described the spatial and temporal spread of α-synuclein pathology in Parkinson's disease. Recent experimental studies have demonstrated that α-synuclein can transfer from cell to cell. In this review, we highlight the involvement of α-synuclein in Parkinson's disease and in Braak's staging of Parkinson's disease pathology. We discuss whether a prion-like mechanism of α-synuclein spread might contribute to Parkinson's disease pathology. We describe recent studies investigating cell-to-cell transfer of α-synuclein and focus our review on the long-distance axonal transport of α-synuclein along neurons.
Collapse
Affiliation(s)
- Sonia George
- Neuronal Survival Unit, Wallenberg Neuroscience Center, Lund University, Lund, Sweden
| | | | | | | | | |
Collapse
|
12
|
Beyer K, Ariza A. Alpha-Synuclein Posttranslational Modification and Alternative Splicing as a Trigger for Neurodegeneration. Mol Neurobiol 2012; 47:509-24. [DOI: 10.1007/s12035-012-8330-5] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Accepted: 08/13/2012] [Indexed: 12/11/2022]
|
13
|
Hansen C, Li JY. Beyond α-synuclein transfer: pathology propagation in Parkinson's disease. Trends Mol Med 2012; 18:248-55. [PMID: 22503115 DOI: 10.1016/j.molmed.2012.03.002] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Revised: 02/29/2012] [Accepted: 03/05/2012] [Indexed: 02/08/2023]
Abstract
α-Synuclein (α-syn) is the most abundant protein found in Lewy bodies, a hallmark of Parkinson's disease (PD), and can aggregate to form toxic oligomers and fibrillar structures. Recent studies have shown that α-syn can be transmitted between neurons and can seed the formation of toxic aggregates in recipient neurons in a prion-like manner. In addition, it is known that Lewy body pathology may spread gradually and systematically from the peripheral or enteric nervous system or olfactory bulb to specific brain regions during progression of idiopathic PD. It is therefore conceivable that α-syn species could act as seeds that drive PD progression. Here, we review recent advances from studies of α-syn cell-to-cell transfer, the current understanding of α-syn toxicity, and how these relate to progression of PD pathology.
Collapse
Affiliation(s)
- Christian Hansen
- Neural Plasticity and Repair Unit, Wallenberg Neuroscience Center, Lund University, BMC A10 22184, Lund, Sweden
| | | |
Collapse
|
14
|
Horvath I, Weise CF, Andersson EK, Chorell E, Sellstedt M, Bengtsson C, Olofsson A, Hultgren SJ, Chapman M, Wolf-Watz M, Almqvist F, Wittung-Stafshede P. Mechanisms of protein oligomerization: inhibitor of functional amyloids templates α-synuclein fibrillation. J Am Chem Soc 2012; 134:3439-44. [PMID: 22260746 PMCID: PMC3290101 DOI: 10.1021/ja209829m] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Small organic molecules that inhibit functional bacterial amyloid fibers, curli, are promising new antibiotics. Here we investigated the mechanism by which the ring-fused 2-pyridone FN075 inhibits fibrillation of the curli protein CsgA. Using a variety of biophysical techniques, we found that FN075 promotes CsgA to form off-pathway, non-amyloidogenic oligomeric species. In light of the generic properties of amyloids, we tested whether FN075 would also affect the fibrillation reaction of human α-synuclein, an amyloid-forming protein involved in Parkinson's disease. Surprisingly, FN075 stimulates α-synuclein amyloid fiber formation as measured by thioflavin T emission, electron microscopy (EM), and atomic force microscopy (AFM). NMR data on (15)N-labeled α-synuclein show that upon FN075 addition, α-synuclein oligomers with 7 nm radius form in which the C-terminal 40 residues remain disordered and solvent exposed. The polypeptides in these oligomers contain β-like secondary structure, and the oligomers are detectable by AFM, EM, and size-exclusion chromatography (SEC). Taken together, FN075 triggers oligomer formation of both proteins: in the case of CsgA, the oligomers do not proceed to fibers, whereas for α-synuclein, the oligomers are poised to rapidly form fibers. We conclude that there is a fine balance between small-molecule inhibition and templation that depends on protein chemistry.
Collapse
Affiliation(s)
- Istvan Horvath
- Department of Chemistry, Chemical Biological Center, Umeå University, 901 87 Umeå, Sweden
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Abstract
AbstractGenetic, neuropathological and biochemical evidence implicates α-synuclein, a 140 amino acid presynaptic neuronal protein, in the pathogenesis of Parkinson’s disease and other neurodegenerative disorders. The aggregated protein inclusions mainly containing aberrant α-synuclein are widely accepted as morphological hallmarks of α-synucleinopathies, but their composition and location vary between disorders along with neuronal networks affected. α-Synuclein exists physiologically in both soluble and membran-bound states, in unstructured and α-helical conformations, respectively, while posttranslational modifications due to proteostatic deficits are involved in β-pleated aggregation resulting in formation of typical inclusions. The physiological function of α-synuclein and its role linked to neurodegeneration, however, are incompletely understood. Soluble oligomeric, not fully fibrillar α-synuclein is thought to be neurotoxic, main targets might be the synapse, axons and glia. The effects of aberrant α-synuclein include alterations of calcium homeostasis, mitochondrial dysfunction, oxidative and nitric injuries, cytoskeletal effects, and neuroinflammation. Proteasomal dysfunction might be a common mechanism in the pathogenesis of neuronal degeneration in α-synucleinopathies. However, how α-synuclein induces neurodegeneration remains elusive as its physiological function. Genome wide association studies demonstrated the important role for genetic variants of the SNCA gene encoding α-synuclein in the etiology of Parkinson’s disease, possibly through effects on oxidation, mitochondria, autophagy, and lysosomal function. The neuropathology of synucleinopathies and the role of α-synuclein as a potential biomarker are briefly summarized. Although animal models provided new insights into the pathogenesis of Parkinson disease and multiple system atrophy, most of them do not adequately reproduce the cardinal features of these disorders. Emerging evidence, in addition to synergistic interactions of α-synuclein with various pathogenic proteins, suggests that prionlike induction and seeding of α-synuclein could lead to the spread of the pathology and disease progression. Intervention in the early aggregation pathway, aberrant cellular effects, or secretion of α-synuclein might be targets for neuroprotection and disease-modifying therapy.
Collapse
|
16
|
Rochet JC, Hay BA, Guo M. Molecular insights into Parkinson's disease. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2012; 107:125-88. [PMID: 22482450 DOI: 10.1016/b978-0-12-385883-2.00011-4] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Mutations in SNCA, PINK1, parkin, and DJ-1 are associated with autosomal-dominant or autosomal-recessive forms of Parkinson's disease (PD), the second most common neurodegenerative disorder. Studies on the structural and functional properties of the corresponding gene products have provided significant insights into the molecular underpinnings of familial PD and the much more common sporadic forms of the disease. Here, we review recent advances in our understanding of four PD-related gene products: α-synuclein, parkin, PINK1, and DJ-1. In Part 1, we review new insights into the role of α-synuclein in PD. In Part 2, we summarize the latest developments in understanding the role of mitochondrial dysfunction in PD, emphasizing the role of the PINK1/parkin pathway in regulating mitochondrial dynamics and mitophagy. The role of DJ-1 is also discussed. In Part 3, we point out converging pathways and future directions.
Collapse
Affiliation(s)
- Jean-Christophe Rochet
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana, USA
| | | | | |
Collapse
|
17
|
Olanow CW, McNaught K. Parkinson's disease, proteins, and prions: Milestones. Mov Disord 2011; 26:1056-71. [DOI: 10.1002/mds.23767] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
|
18
|
Lewis KA, Su Y, Jou O, Ritchie C, Foong C, Hynan LS, White CL, Thomas PJ, Hatanpaa KJ. Abnormal neurites containing C-terminally truncated alpha-synuclein are present in Alzheimer's disease without conventional Lewy body pathology. THE AMERICAN JOURNAL OF PATHOLOGY 2010; 177:3037-50. [PMID: 21056999 DOI: 10.2353/ajpath.2010.100552] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The pathological hallmark of Parkinson's disease and diffuse Lewy body disease (DLBD) is the aggregation of α-synuclein (α-syn) in the form of Lewy bodies and Lewy neurites. Patients with both Alzheimer's disease (AD) and cortical Lewy pathology represent the Lewy body variant of AD (LBV) and constitute 25% of AD cases. C-terminally truncated forms of α-syn enhance the aggregation of α-syn in vitro. To investigate the presence of C-terminally truncated α-syn in DLBD, AD, and LBV, we generated and validated polyclonal antibodies to truncated α-syn ending at residues 110 (α-syn110) and 119 (α-syn119), two products of 20S proteosome-mediated endoproteolytic cleavage. Double immunofluorescence staining of the cingulate cortex showed that α-syn110 and α-syn140 (full-length) aggregates were not colocalized in LBV. All aggregates containing α-syn140 also contained α-syn119; however, some aggregates contained α-syn119 without α-syn140, suggesting that α-syn119 may stimulate aggregate formation. Immunohistochemistry and image analysis of tissue microarrays of the cingulate cortex from patients with DLBD (n = 27), LBV (n = 27), and AD (n = 19) and age-matched controls (n = 15) revealed that AD is also characterized by frequent abnormal neurites containing α-syn119. Notably, these neurites did not contain α-syn ending at residues 110 or 122-140. The presence of abnormal neurites containing α-syn119 in AD without conventional Lewy pathology suggests that AD and Lewy body disease may be more closely related than previously thought.
Collapse
Affiliation(s)
- Karen A Lewis
- Graduate Program in Molecular Biophysics, Department of Physiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Oueslati A, Fournier M, Lashuel HA. Role of post-translational modifications in modulating the structure, function and toxicity of alpha-synuclein: implications for Parkinson's disease pathogenesis and therapies. PROGRESS IN BRAIN RESEARCH 2010; 183:115-45. [PMID: 20696318 DOI: 10.1016/s0079-6123(10)83007-9] [Citation(s) in RCA: 264] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A better understanding of the molecular and cellular determinants that influence the pathology of Parkinson's disease (PD) is essential for developing effective diagnostic, preventative and therapeutic strategies to treat this devastating disease. A number of post-translational modifications to alpha-syn are present within the Lewy bodies in the brains of affected patients and transgenic models of PD and related disorders. However, whether disease-associated alpha-syn post-translational modifications promote or inhibit alpha-syn aggregation and neurotoxicity in vivo remains unknown. Herein, we summarize and discuss the major disease-associated post-translational modifications (phosphorylation, truncation and ubiquitination) and present our current understanding of the effect of these modifications on alpha-syn aggregation and toxicity. Elucidating the molecular mechanisms underlying post-translation modifications of alpha-syn and the consequences of such modifications on the biochemical, structural, aggregation and toxic properties of the protein is essential for unravelling the molecular basis of its function(s) in health and disease. Furthermore, the identification of the natural enzymes involved in regulating the post-translational modifications of alpha-synuclein will yield novel and more tractable therapeutic targets to treat PD and related synucleinopathies.
Collapse
Affiliation(s)
- Abid Oueslati
- Laboratory of Molecular Neurobiology and Neuroproteomics, Brain Mind Institute, The Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | | | | |
Collapse
|