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Varesi A, Campagnoli LIM, Barbieri A, Rossi L, Ricevuti G, Esposito C, Chirumbolo S, Marchesi N, Pascale A. RNA binding proteins in senescence: A potential common linker for age-related diseases? Ageing Res Rev 2023; 88:101958. [PMID: 37211318 DOI: 10.1016/j.arr.2023.101958] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 05/09/2023] [Accepted: 05/18/2023] [Indexed: 05/23/2023]
Abstract
Aging represents the major risk factor for the onset and/or progression of various disorders including neurodegenerative diseases, metabolic disorders, and bone-related defects. As the average age of the population is predicted to exponentially increase in the coming years, understanding the molecular mechanisms underlying the development of aging-related diseases and the discovery of new therapeutic approaches remain pivotal. Well-reported hallmarks of aging are cellular senescence, genome instability, autophagy impairment, mitochondria dysfunction, dysbiosis, telomere attrition, metabolic dysregulation, epigenetic alterations, low-grade chronic inflammation, stem cell exhaustion, altered cell-to-cell communication and impaired proteostasis. With few exceptions, however, many of the molecular players implicated within these processes as well as their role in disease development remain largely unknown. RNA binding proteins (RBPs) are known to regulate gene expression by dictating at post-transcriptional level the fate of nascent transcripts. Their activity ranges from directing primary mRNA maturation and trafficking to modulation of transcript stability and/or translation. Accumulating evidence has shown that RBPs are emerging as key regulators of aging and aging-related diseases, with the potential to become new diagnostic and therapeutic tools to prevent or delay aging processes. In this review, we summarize the role of RBPs in promoting cellular senescence and we highlight their dysregulation in the pathogenesis and progression of the main aging-related diseases, with the aim of encouraging further investigations that will help to better disclose this novel and captivating molecular scenario.
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Affiliation(s)
- Angelica Varesi
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy.
| | | | - Annalisa Barbieri
- Department of Drug Sciences, Section of Pharmacology, University of Pavia, Pavia, Italy
| | - Lorenzo Rossi
- Institute of Molecular Biology and Biophysics, ETH Zurich, Zurich, Switzerland
| | | | - Ciro Esposito
- Department of Internal Medicine and Therapeutics, University of Pavia, Italy; Nephrology and dialysis unit, ICS S. Maugeri SPA SB Hospital, Pavia, Italy; High School in Geriatrics, University of Pavia, Italy
| | | | - Nicoletta Marchesi
- Department of Drug Sciences, Section of Pharmacology, University of Pavia, Pavia, Italy
| | - Alessia Pascale
- Department of Drug Sciences, Section of Pharmacology, University of Pavia, Pavia, Italy.
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2
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Lazo PA, Morejón-García P. VRK1 variants at the cross road of Cajal body neuropathogenic mechanisms in distal neuropathies and motor neuron diseases. Neurobiol Dis 2023; 183:106172. [PMID: 37257665 DOI: 10.1016/j.nbd.2023.106172] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 05/09/2023] [Accepted: 05/24/2023] [Indexed: 06/02/2023] Open
Abstract
Distal hereditary neuropathies and neuro motor diseases are complex neurological phenotypes associated with pathogenic variants in a large number of genes, but in some the origin is unknown. Recently, rare pathogenic variants of the human VRK1 gene have been associated with these neurological phenotypes. All VRK1 pathogenic variants are recessive, and their clinical presentation occurs in either homozygous or compound heterozygous patients. The pathogenic VRK1 gene pathogenic variants are located in three clusters within the protein sequence. The main, and initial, shared clinical phenotype among VRK1 pathogenic variants is a distal progressive loss of motor and/or sensory function, which includes diseases such as spinal muscular atrophy, Charcot-Marie-Tooth, amyotrophic lateral sclerosis and hereditary spastic paraplegia. In most cases, symptoms start early in infancy, or in utero, and are slowly progressive. Additional neurological symptoms vary among non-related patients, probably because of their different VRK1 variants and their genetic background. The underlying common pathogenic mechanism, by its functional impairment, is a likely consequence of the roles that the VRK1 protein plays in the regulation on the stability and assembly of Cajal bodies, which affect RNA maturation and processing, neuronal migration of RNPs along axons, and DNA-damage responses. Alterations of these processes are associated with several neuro sensory or motor syndromes. The clinical heterogeneity of the neurological phenotypes associated with VRK1 is a likely consequence of the protein complexes in which VRK1 is integrated, which include several proteins known to be associated with Cajal bodies and DNA damage responses. Several hereditary distal neurological diseases are a consequence of pathogenic variants in genes that alter these cellular functions. We conclude that VRK1-related distal hereditary neuropathies and motor neuron diseases represent a novel subgroup of Cajal body related neurological syndromes.
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Affiliation(s)
- Pedro A Lazo
- Molecular Mechanisms of Cancer Program, Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC) - Universidad de Salamanca, Salamanca, Spain; Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, Salamanca, Spain.
| | - Patricia Morejón-García
- Molecular Mechanisms of Cancer Program, Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC) - Universidad de Salamanca, Salamanca, Spain; Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, Salamanca, Spain.
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Sustained therapeutic benefits by transient reduction of TDP-43 using ENA-modified antisense oligonucleotides in ALS/FTD mice. MOLECULAR THERAPY. NUCLEIC ACIDS 2023; 31:353-366. [PMID: 36817728 PMCID: PMC9925842 DOI: 10.1016/j.omtn.2023.01.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 01/12/2023] [Indexed: 01/17/2023]
Abstract
The abnormal aggregation of TDP-43 into cytoplasmic inclusions in affected neurons is a pathological hallmark of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Although how TDP-43 forms cytoplasmic aggregates and causes neurodegeneration in patients with ALS/FTD remains unclear, reducing cellular TDP-43 levels is likely to prevent aggregation and to rescue neurons from TDP-43 toxicity. To address this issue, here we developed gapmer-type antisense oligonucleotides (ASOs) against human TDP-43 using 2'-O,4'-C-ethylene nucleic acids (ENAs), which are modified nucleic acids with high stability, and tested the therapeutic potential of lowering TDP-43 levels using ENA-modified ASOs. We demonstrated that intracerebroventricular administration of ENA-modified ASOs into a mouse model of ALS/FTD expressing human TDP-43 results in the efficient reduction of TDP-43 levels in the brain and spinal cord. Surprisingly, a single injection of ENA-modified ASOs into TDP-43 mice led to long-lasting improvement of behavioral abnormalities and the suppression of cytoplasmic TDP-43 aggregation, even after TDP-43 levels had returned to the initial levels. Our results demonstrate that transient reduction of TDP-43 using ENA-modified ASOs leads to sustained therapeutic benefits in vivo, indicating the possibility of a disease-modifying therapy by lowering TDP-43 levels for the treatment of the TDP-43 proteinopathies, including ALS/FTD.
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TDP-43 drives synaptic and cognitive deterioration following traumatic brain injury. Acta Neuropathol 2022; 144:187-210. [PMID: 35713704 PMCID: PMC9945325 DOI: 10.1007/s00401-022-02449-w] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 05/31/2022] [Accepted: 05/31/2022] [Indexed: 11/01/2022]
Abstract
Traumatic brain injury (TBI) has been recognized as an important risk factor for Alzheimer's disease (AD). However, the molecular mechanisms by which TBI contributes to developing AD remain unclear. Here, we provide evidence that aberrant production of TDP-43 is a key factor in promoting AD neuropathology and synaptic and cognitive deterioration in mouse models of mild closed head injury (CHI). We observed that a single mild CHI is sufficient to exacerbate AD neuropathology and accelerate synaptic and cognitive deterioration in APP transgenic mice but repeated mild CHI are required to induce neuropathological changes and impairments in synaptic plasticity, spatial learning, and memory retention in wild-type animals. Importantly, these changes in animals exposed to a single or repeated mild CHI are alleviated by silencing of TDP-43 but reverted by rescue of the TDP-43 knockdown. Moreover, overexpression of TDP-43 in the hippocampus aggravates AD neuropathology and provokes cognitive impairment in APP transgenic mice, mimicking single mild CHI-induced changes. We further discovered that neuroinflammation triggered by TBI promotes NF-κB-mediated transcription and expression of TDP-43, which in turn stimulates tau phosphorylation and Aβ formation. Our findings suggest that excessive production of TDP-43 plays an important role in exacerbating AD neuropathology and in driving synaptic and cognitive declines following TBI.
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Chavda V, Patel C, Modh D, Ertas YN, Sonak SS, Munshi NK, Anand K, Soni A, Pandey S. Therapeutic Approaches to Amyotrophic Lateral Sclerosis from the Lab to the Clinic. Curr Drug Metab 2022; 23:200-222. [PMID: 35272595 DOI: 10.2174/1389200223666220310113110] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 01/07/2022] [Accepted: 02/02/2022] [Indexed: 11/22/2022]
Abstract
Amyotrophic Lateral Sclerosis (ALS) is a terminal neuro-degenerative disorder that is clinically recognized as a gradual degeneration of the upper and lower motor neurons, with an average duration of 3 to 5 years from initiation of symptoms to death. The mechanisms underlying the pathogenesis and progression of the disease are multifactorial. Therefore, to find effective treatments, it is necessary to understand this heterogeneity underlying the progression of ALS. Recent developments in gene therapy have opened a new avenue to treat this condition, especially for the characterized genetic types. Gene therapy methods have been studied in a variety of pre-clinical settings and clinical trials, and they may be a promising path for developing an effective and safe ALS cure. A growing body of evidence demonstrates abnormalities in energy metabolism at the cellular and whole-body level in animal models and in people living with ALS. The use and incorporation of high-throughput "omics" methods has radically transformed our thought about ALS, strengthening our understanding of the disease's dynamic molecular architecture, differentiating distinct patient subtypes, and creating a reasonable basis for the identification of biomarkers and novel individualised treatments. Future clinical and laboratory trials would also focus on the diverse relationships between metabolism and ALS to address the issue of whether targeting deficient metabolism in ALS is an effective way to change disease progression. In this review, we focus on the detailed pathogenesis of ALS and highlight principal genes, i.e., SOD1, TDP-43, C9orf72, and FUS, targeted therapeutic approaches of ALS. An attempt is made to provide up-to-date information on clinical outcomes, including various biomarkers which are thought to be important players in early ALS detection.
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Affiliation(s)
- Vivek Chavda
- Department of Pharmaceutic, L M College of Pharmacy, Ahmedabad - 380009 (India)
| | - Chirag Patel
- Department of Pharmacology, L M College of Pharmacy, Ahmedabad - 380009 (India)
| | - Dharti Modh
- Department of pharmaceutical chemistry, Poona college of pharmacy, Bharti vidhyapith, Pune - 411030 (India)
| | - Yavuz Nuri Ertas
- Department of Biomedical Engineering at Erciyes University, Kayseri, Turkey
- ERNAM - Nanotechnology Research and Application Center, Erciyes University, Kayseri 38039, Turkey
| | - Shreya S Sonak
- Department of pharmaceutical chemistry, Poona college of pharmacy, Bharti vidhyapith, Pune - 411030 (India)
| | - Nafisa K Munshi
- Department of pharmaceutical chemistry, Poona college of pharmacy, Bharti vidhyapith, Pune - 411030 (India)
| | - Krishna Anand
- Department of Chemical Pathology, School of Pathology, Faculty of Health Sciences and National Health Laboratory Service, University of the Free State, Bloemfontein 9300, South Africa
| | - Arun Soni
- Department of Pharmacology, SSR College of Pharmacy, Silvassa, Dadra and Nagar Haveli - 396230(India)
| | - Sonal Pandey
- Research and Development, Meril Diagnostic Pvt. Ltd, Vapi - 396191 (India)
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Molecular Pathways Involved in Frontotemporal Lobar Degeneration with TDP-43 Proteinopathy: What Can We Learn from Proteomics? Int J Mol Sci 2021; 22:ijms221910298. [PMID: 34638637 PMCID: PMC8508653 DOI: 10.3390/ijms221910298] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 09/17/2021] [Accepted: 09/22/2021] [Indexed: 12/14/2022] Open
Abstract
Frontotemporal lobar degeneration (FTLD) is a neurodegenerative disorder clinically characterized by behavioral, language, and motor symptoms, with major impact on the lives of patients and their families. TDP-43 proteinopathy is the underlying neuropathological substrate in the majority of cases, referred to as FTLD-TDP. Several genetic causes have been identified, which have revealed some components of its pathophysiology. However, the exact mechanisms driving FTLD-TDP remain largely unknown, forestalling the development of therapies. Proteomic approaches, in particular high-throughput mass spectrometry, hold promise to help elucidate the pathogenic molecular and cellular alterations. In this review, we describe the main findings of the proteomic profiling studies performed on human FTLD-TDP brain tissue. Subsequently, we address the major biological pathways implicated in FTLD-TDP, by reviewing these data together with knowledge derived from genomic and transcriptomic literature. We illustrate that an integrated perspective, encompassing both proteomic, genetic, and transcriptomic discoveries, is vital to unravel core disease processes, and to enable the identification of disease biomarkers and therapeutic targets for this devastating disorder.
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Hallegger M, Chakrabarti AM, Lee FCY, Lee BL, Amalietti AG, Odeh HM, Copley KE, Rubien JD, Portz B, Kuret K, Huppertz I, Rau F, Patani R, Fawzi NL, Shorter J, Luscombe NM, Ule J. TDP-43 condensation properties specify its RNA-binding and regulatory repertoire. Cell 2021; 184:4680-4696.e22. [PMID: 34380047 PMCID: PMC8445024 DOI: 10.1016/j.cell.2021.07.018] [Citation(s) in RCA: 108] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 04/12/2021] [Accepted: 07/15/2021] [Indexed: 11/20/2022]
Abstract
Mutations causing amyotrophic lateral sclerosis (ALS) often affect the condensation properties of RNA-binding proteins (RBPs). However, the role of RBP condensation in the specificity and function of protein-RNA complexes remains unclear. We created a series of TDP-43 C-terminal domain (CTD) variants that exhibited a gradient of low to high condensation propensity, as observed in vitro and by nuclear mobility and foci formation. Notably, a capacity for condensation was required for efficient TDP-43 assembly on subsets of RNA-binding regions, which contain unusually long clusters of motifs of characteristic types and density. These "binding-region condensates" are promoted by homomeric CTD-driven interactions and required for efficient regulation of a subset of bound transcripts, including autoregulation of TDP-43 mRNA. We establish that RBP condensation can occur in a binding-region-specific manner to selectively modulate transcriptome-wide RNA regulation, which has implications for remodeling RNA networks in the context of signaling, disease, and evolution.
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Affiliation(s)
- Martina Hallegger
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK; Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK.
| | - Anob M Chakrabarti
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK; Department of Genetics, Evolution and Environment, UCL Genetics Institute, Gower Street, London WC1E 6BT, UK
| | - Flora C Y Lee
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK; Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Bo Lim Lee
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Aram G Amalietti
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK; Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK; National Institute of Chemistry, Hajdrihova 19, 1001 Ljubljana, Slovenia
| | - Hana M Odeh
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Katie E Copley
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA; Neuroscience Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jack D Rubien
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Bede Portz
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Klara Kuret
- National Institute of Chemistry, Hajdrihova 19, 1001 Ljubljana, Slovenia
| | - Ina Huppertz
- European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Frédérique Rau
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK; Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Rickie Patani
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK; Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Nicolas L Fawzi
- Department of Molecular Pharmacology, Physiology, and Biotechnology, Brown University, Providence, RI 02912, USA
| | - James Shorter
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA; Neuroscience Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Nicholas M Luscombe
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK; Department of Genetics, Evolution and Environment, UCL Genetics Institute, Gower Street, London WC1E 6BT, UK; Okinawa Institute of Science & Technology Graduate University, 1919-1 Tancha, Onna-son, Kunigami-gun, Okinawa 904-0495, Japan
| | - Jernej Ule
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK; Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK; National Institute of Chemistry, Hajdrihova 19, 1001 Ljubljana, Slovenia.
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Giunta M, Solje E, Gardoni F, Borroni B, Benussi A. Experimental Disease-Modifying Agents for Frontotemporal Lobar Degeneration. J Exp Pharmacol 2021; 13:359-376. [PMID: 33790662 PMCID: PMC8005747 DOI: 10.2147/jep.s262352] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 03/09/2021] [Indexed: 12/11/2022] Open
Abstract
Frontotemporal dementia is a clinically, genetically and pathologically heterogeneous neurodegenerative disorder, enclosing a wide range of different pathological entities, associated with the accumulation of proteins such as tau and TPD-43. Characterized by a high hereditability, mutations in three main genes, MAPT, GRN and C9orf72, can drive the neurodegenerative process. The connection between different genes and proteinopathies through specific mechanisms has shed light on the pathophysiology of the disease, leading to the identification of potential pharmacological targets. New experimental strategies are emerging, in both preclinical and clinical settings, which focus on small molecules rather than gene therapy. In this review, we provide an insight into the aberrant mechanisms leading to FTLD-related proteinopathies and discuss recent therapies with the potential to ameliorate neurodegeneration and disease progression.
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Affiliation(s)
- Marcello Giunta
- Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Eino Solje
- Institute of Clinical Medicine - Neurology, University of Eastern Finland, Kuopio, Finland
| | - Fabrizio Gardoni
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Barbara Borroni
- Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Alberto Benussi
- Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
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Huang C, Yan S, Zhang Z. Maintaining the balance of TDP-43, mitochondria, and autophagy: a promising therapeutic strategy for neurodegenerative diseases. Transl Neurodegener 2020; 9:40. [PMID: 33126923 PMCID: PMC7597011 DOI: 10.1186/s40035-020-00219-w] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 10/14/2020] [Indexed: 02/06/2023] Open
Abstract
Mitochondria are the energy center of cell operations and are involved in physiological functions and maintenance of metabolic balance and homeostasis in the body. Alterations of mitochondrial function are associated with a variety of degenerative and acute diseases. As mitochondria age in cells, they gradually become inefficient and potentially toxic. Acute injury can trigger the permeability of mitochondrial membranes, which can lead to apoptosis or necrosis. Transactive response DNA-binding protein 43 kDa (TDP-43) is a protein widely present in cells. It can bind to RNA, regulate a variety of RNA processes, and play a role in the formation of multi-protein/RNA complexes. Thus, the normal physiological functions of TDP-43 are particularly important for cell survival. Normal TDP-43 is located in various subcellular structures including mitochondria, mitochondrial-associated membrane, RNA particles and stress granules to regulate the endoplasmic reticulum–mitochondrial binding, mitochondrial protein translation, and mRNA transport and translation. Importantly, TDP-43 is associated with a variety of neurodegenerative diseases, including amyotrophic lateral sclerosis, frontotemporal dementia and Alzheimer's disease, which are characterized by abnormal phosphorylation, ubiquitination, lysis or nuclear depletion of TDP-43 in neurons and glial cells. Although the pathogenesis of TDP-43 proteinopathy remains unknown, the presence of pathological TDP-43 inside or outside of mitochondria and the functional involvement of TDP-43 in the regulation of mitochondrial morphology, transport, and function suggest that mitochondria are associated with TDP-43-related diseases. Autophagy is a basic physiological process that maintains the homeostasis of cells, including targeted clearance of abnormally aggregated proteins and damaged organelles in the cytoplasm; therefore, it is considered protective against neurodegenerative diseases. However, the combination of abnormal TDP-43 aggregation, mitochondrial dysfunction, and insufficient autophagy can lead to a variety of aging-related pathologies. In this review, we describe the current knowledge on the associations of mitochondria with TDP-43 and the role of autophagy in the clearance of abnormally aggregated TDP-43 and dysfunctional mitochondria. Finally, we discuss a novel approach for neurodegenerative treatment based on the knowledge.
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Affiliation(s)
- Chunhui Huang
- Institute of New Drug Research, Guangdong Province Key Laboratory of Pharmacodynamic, Constituents of Traditional Chinese Medicine and New Drug Research, College of Pharmacy, Jinan University, Guangzhou, 510632, China
| | - Sen Yan
- Ministry of Education CNS Regeneration Collaborative Joint Laboratory, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, 510632, China.
| | - Zaijun Zhang
- Institute of New Drug Research, Guangdong Province Key Laboratory of Pharmacodynamic, Constituents of Traditional Chinese Medicine and New Drug Research, College of Pharmacy, Jinan University, Guangzhou, 510632, China.
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10
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Ishikawa K, Nagai Y. Molecular Mechanisms and Future Therapeutics for Spinocerebellar Ataxia Type 31 (SCA31). Neurotherapeutics 2019; 16:1106-1114. [PMID: 31755042 PMCID: PMC6985187 DOI: 10.1007/s13311-019-00804-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Spinocerebellar ataxia type 31 (SCA31) is one of the autosomal-dominant neurodegenerative disorders that shows progressive cerebellar ataxia as a cardinal symptom. This disease is caused by a 2.5- to 3.8-kb-long complex pentanucleotide repeat containing (TGGAA)n, (TAGAA)n, (TAAAA)n, and (TAAAATAGAA)n in an intron of the gene called BEAN1 (brain expressed, associated with Nedd4). By comparing various pentanucleotide repeats in this particular locus among control Japanese and Caucasian populations, it was found that (TGGAA)n was the only sequence segregating with SCA31, strongly suggesting the pathogenicity of (TGGAA)n. The complex repeat also lies in an intron of another gene, TK2 (thymidine kinase 2), which is transcribed in the opposite direction, indicating that the complex repeat is bi-directionally transcribed as noncoding repeats. In SCA31 human brains, (UGGAA)n, the BEAN1 transcript of SCA31 mutation was found to form abnormal RNA structures called RNA foci in cerebellar Purkinje cell nuclei. Subsequent RNA pulldown analysis disclosed that (UGGAA)n binds to RNA-binding proteins TDP-43, FUS, and hnRNP A2/B1. In fact, TDP-43 was found to co-localize with RNA foci in human SCA31 Purkinje cells. To dissect the pathogenesis of (UGGAA)n in SCA31, we generated transgenic fly models of SCA31 by overexpressing SCA31 complex pentanucleotide repeats in Drosophila. We found that the toxicity of (UGGAA)n is length- and expression level-dependent, and it was dampened by co-expressing TDP-43, FUS, and hnRNP A2/B1. Further investigation revealed that TDP-43 ameliorates (UGGAA)n toxicity by directly fixing the abnormal structure of (UGGAA)n. This led us to propose that TDP-43 acts as an RNA chaperone against toxic (UGGAA)n. Further research on the role of RNA-binding proteins as RNA chaperones may provide a novel therapeutic strategy for SCA31.
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Affiliation(s)
- Kinya Ishikawa
- Department of Neurology and Neurological Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan.
- The Center for Personalized Medicine for Healthy Aging, Tokyo Medical and Dental University, Tokyo, Japan.
| | - Yoshitaka Nagai
- Department of Neurotherapeutics, Osaka University Graduate School of Medicine, Osaka, Japan
- Department of Degenerative Neurological Diseases, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Japan
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11
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Palomo V, Tosat-Bitrian C, Nozal V, Nagaraj S, Martin-Requero A, Martinez A. TDP-43: A Key Therapeutic Target beyond Amyotrophic Lateral Sclerosis. ACS Chem Neurosci 2019; 10:1183-1196. [PMID: 30785719 DOI: 10.1021/acschemneuro.9b00026] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Accumulation of TDP-43 in the cytoplasm of diseased neurons is the pathological hallmark of frontotemporal dementia-TDP (FTLD-TDP) and amyotrophic lateral sclerosis (ALS), two diseases that lack efficacious medicine to prevent or to stop disease progression. The discovery of mutations in the TARDBP gene (encoding the nuclear protein known as TDP-43) in both FTLD and ALS patients provided evidence for a link between TDP-43 alterations and neurodegeneration. Our understanding of TDP-43 function has advanced profoundly in the past several years; however, its complete role and the molecular mechanisms that lead to disease are not fully understood. Here we summarize the recent studies of this protein, its relation to neurodegenerative diseases, and the therapeutic strategies for restoring its homeostasis with small molecules. Finally, we briefly discuss the available cellular and animal models that help to shed light on TDP-43 pathology and could serve as tools for the discovery of pharmacological agents for the treatment of TDP-43-related diseases.
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Affiliation(s)
- Valle Palomo
- Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Instituto Carlos III, 28031 Madrid, Spain
| | | | - Vanesa Nozal
- Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Siranjeevi Nagaraj
- Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Angeles Martin-Requero
- Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Instituto Carlos III, 28031 Madrid, Spain
| | - Ana Martinez
- Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Instituto Carlos III, 28031 Madrid, Spain
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12
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Pozzi S, Thammisetty SS, Codron P, Rahimian R, Plourde KV, Soucy G, Bareil C, Phaneuf D, Kriz J, Gravel C, Julien JP. Virus-mediated delivery of antibody targeting TAR DNA-binding protein-43 mitigates associated neuropathology. J Clin Invest 2019; 129:1581-1595. [PMID: 30667370 DOI: 10.1172/jci123931] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 01/15/2019] [Indexed: 12/12/2022] Open
Abstract
The cytoplasmic aggregation of TAR DNA-binding protein-43 (TDP-43) is a hallmark of degenerating neurons in amyotrophic lateral sclerosis (ALS) and subsets of frontotemporal dementia (FTD). In order to reduce TDP-43 pathology, we generated single-chain (scFv) antibodies against the RNA recognition motif 1 (RRM1) of TDP-43, which is involved in abnormal protein self-aggregation and interaction with p65 NF-κB. Virus-mediated delivery into the nervous system of a scFv antibody, named VH7Vk9, reduced microgliosis in a mouse model of acute neuroinflammation and mitigated cognitive impairment, motor defects, TDP-43 proteinopathy, and neuroinflammation in transgenic mice expressing ALS-linked TDP-43 mutations. These results suggest that antibodies targeting the RRM1 domain of TDP-43 might provide new therapeutic avenues for the treatment of ALS and FTD.
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Affiliation(s)
- Silvia Pozzi
- CERVO Brain Research Centre, Québec, Québec, Canada
| | | | - Philippe Codron
- CERVO Brain Research Centre, Québec, Québec, Canada.,MITOVASC Institute, Centre National de la Recherche Scientifique (CNRS) 6015, INSERM U1083, University of Angers, Angers, France
| | | | | | | | | | | | - Jasna Kriz
- CERVO Brain Research Centre, Québec, Québec, Canada.,Department of Psychiatry and Neuroscience, Université Laval, Québec City, Québec, Canada
| | - Claude Gravel
- CERVO Brain Research Centre, Québec, Québec, Canada.,Department of Psychiatry and Neuroscience, Université Laval, Québec City, Québec, Canada
| | - Jean-Pierre Julien
- CERVO Brain Research Centre, Québec, Québec, Canada.,Department of Psychiatry and Neuroscience, Université Laval, Québec City, Québec, Canada
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13
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Newell K, Paron F, Mompean M, Murrell J, Salis E, Stuani C, Pattee G, Romano M, Laurents D, Ghetti B, Buratti E. Dysregulation of TDP-43 intracellular localization and early onset ALS are associated with a TARDBP S375G variant. Brain Pathol 2018; 29:397-413. [PMID: 30461104 PMCID: PMC6875182 DOI: 10.1111/bpa.12680] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 11/12/2018] [Indexed: 02/06/2023] Open
Abstract
We investigated the Central Nervous System (CNS) and skeletal muscle tissue from A woman was clinically diagnosed with amyotrophic lateral sclerosis (ALS) at the age of 22. Neuropathologic evaluation showed upper and lower motor neuron loss, corticospinal tract degeneration and skeletal muscle denervation. Analysis of the patient's Deoxyribonucleic acid (DNA) revealed a AGT>GGT change resulting in an S375G substitution in the C-terminal region of TDP-43. This variant was previously reported as being benign. Considering the early onset and severity of the disease in this patient, we tested the effects of this genetic variant on TDP-43 localization, pre-mRNA splicing activity and toxicity, in parallel with the effects on known neighboring disease-associated mutations. In cell lines, expressed in culture, S375G TDP-43 appeared to be more significantly localized in the nucleus and to exert higher toxicity than wild-type TDP-43. Strikingly, a phosphomimic mutant at the same residue (S375E) showed a strong tendency to accumulate in the cytoplasm, especially under stress conditions, and molecular dynamics simulations suggest that phosphorylation of this residue can disrupt TDP-43 intermolecular interactions. The results of the current study highlight the importance of phosphorylation and regulation of TDP-43 nuclear-cytoplasmic shuttling/redistribution, in relation to the pathogenetic mechanisms involved in different forms of ALS.
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Affiliation(s)
- Kathy Newell
- University of Kansas School of Medicine, Pathology & Laboratory Medicine, Kansas City, MO
| | - Francesca Paron
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Trieste, Italy
| | - Miguel Mompean
- University of Castile-La Mancha, Instituto Regional de Investigación Científica Aplicada (IRICA), Ciudad Real, Spain
| | - Jill Murrell
- Indiana University School of Medicine, Pathology & Laboratory Medicine, Indianapolis, IN
| | - Elisa Salis
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Trieste, Italy
| | - Cristiana Stuani
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Trieste, Italy
| | - Gary Pattee
- University of Nebraska Medical Center, Lincoln, NE
| | - Maurizio Romano
- Department of Life Sciences, University of Trieste, Trieste, Italy
| | - Douglas Laurents
- Instituto de Química Física "Rocasolano", Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Bernardino Ghetti
- Indiana University School of Medicine, Pathology & Laboratory Medicine, Indianapolis, IN
| | - Emanuele Buratti
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Trieste, Italy
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14
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Choi KJ, Tsoi PS, Moosa MM, Paulucci-Holthauzen A, Liao SCJ, Ferreon JC, Ferreon ACM. A Chemical Chaperone Decouples TDP-43 Disordered Domain Phase Separation from Fibrillation. Biochemistry 2018; 57:6822-6826. [PMID: 30520303 DOI: 10.1021/acs.biochem.8b01051] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Ribonucleoprotein (RNP) condensations through liquid-liquid phase separation play vital roles in the dynamic formation-dissolution of stress granules (SGs). These condensations are, however, usually assumed to be linked to pathologic fibrillation. Here, we show that physiologic condensation and pathologic fibrillation of RNPs are independent processes that can be unlinked with the chemical chaperone trimethylamine N-oxide (TMAO). Using the low-complexity disordered domain of the archetypical SG-protein TDP-43 as a model system, we show that TMAO enhances RNP liquid condensation yet inhibits protein fibrillation. Our results demonstrate effective decoupling of physiologic condensation from pathologic aggregation and suggest that selective targeting of protein fibrillation (without altering condensation) can be employed as a therapeutic strategy for RNP aggregation-associated degenerative disorders.
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Affiliation(s)
- Kyoung-Jae Choi
- Department of Pharmacology and Chemical Biology , Baylor College of Medicine , One Baylor Plaza, N520.03 , Houston , Texas 77030 , United States
| | - Phoebe S Tsoi
- Department of Pharmacology and Chemical Biology , Baylor College of Medicine , One Baylor Plaza, N520.03 , Houston , Texas 77030 , United States
| | - Mahdi Muhammad Moosa
- Department of Pharmacology and Chemical Biology , Baylor College of Medicine , One Baylor Plaza, N520.03 , Houston , Texas 77030 , United States
| | - Adriana Paulucci-Holthauzen
- Department of Genetics , The University of Texas M. D. Anderson Cancer Center , Houston , Texas 77030 , United States
| | - Shih-Chu Jeff Liao
- ISS, Inc. , 1602 Newton Drive , Champaign , Illinois 61822 , United States
| | - Josephine C Ferreon
- Department of Pharmacology and Chemical Biology , Baylor College of Medicine , One Baylor Plaza, N520.03 , Houston , Texas 77030 , United States
| | - Allan Chris M Ferreon
- Department of Pharmacology and Chemical Biology , Baylor College of Medicine , One Baylor Plaza, N520.03 , Houston , Texas 77030 , United States
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15
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Theme 2 In vitro experimental models. Amyotroph Lateral Scler Frontotemporal Degener 2018; 19:112-129. [DOI: 10.1080/21678421.2018.1510569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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16
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Trist BG, Hare DJ, Double KL. A Proposed Mechanism for Neurodegeneration in Movement Disorders Characterized by Metal Dyshomeostasis and Oxidative Stress. Cell Chem Biol 2018; 25:807-816. [PMID: 29861271 DOI: 10.1016/j.chembiol.2018.05.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 04/09/2018] [Accepted: 05/01/2018] [Indexed: 02/07/2023]
Abstract
Shared molecular pathologies between distinct neurodegenerative disorders offer unique opportunities to identify common mechanisms of neuron death, and apply lessons learned from one disease to another. Neurotoxic superoxide dismutase 1 (SOD1) proteinopathy in SOD1-associated familial amyotrophic lateral sclerosis (fALS) is recapitulated in idiopathic Parkinson disease (PD), suggesting that these two phenotypically distinct disorders share an etiological pathway, and tractable therapeutic target(s). Despite 25 years of research, the molecular determinants underlying SOD1 misfolding and toxicity in fALS remain poorly understood. The absence of SOD1 mutations in PD highlights mounting evidence that SOD1 mutations are not the sole cause of SOD1 protein misfolding occasioning oligomerization and toxicity, reinforcing the importance of non-genetic factors, including protein metallation and post-translational modification in determining SOD1 stability and function. We propose that these non-genetic factors underlie the misfolding and dysfunction of SOD1 and other proteins in both PD and fALS, constituting a shared and tractable pathway to neurodegeneration.
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Affiliation(s)
- Benjamin Guy Trist
- Discipline of Biomedical Science and Brain and Mind Centre, Sydney Medical School, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2050, Australia
| | - Dominic James Hare
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC 3052, Australia; Department of Pathology, The University of Melbourne, Parkville, VIC 3052, Australia
| | - Kay Lorraine Double
- Discipline of Biomedical Science and Brain and Mind Centre, Sydney Medical School, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2050, Australia.
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17
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Shenouda M, Zhang AB, Weichert A, Robertson J. Mechanisms Associated with TDP-43 Neurotoxicity in ALS/FTLD. ADVANCES IN NEUROBIOLOGY 2018; 20:239-263. [PMID: 29916022 DOI: 10.1007/978-3-319-89689-2_9] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The discovery of TDP-43 as a major disease protein in amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) was first made in 2006. Prior to 2006 there were only 11 publications related to TDP-43, now there are over 2000, indicating the importance of TDP-43 to unraveling the complex molecular mechanisms that underpin the pathogenesis of ALS/FTLD. Subsequent to this discovery, TDP-43 pathology was also found in other neurodegenerative diseases, including Alzheimer's disease, the significance of which is still in the early stages of exploration. TDP-43 is a predominantly nuclear DNA/RNA-binding protein, one of a number of RNA-binding proteins that are now known to be linked with ALS/FTLD, including Fused in Sarcoma (FUS), heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1), and heterogeneous nuclear ribonucleoprotein A2/B1 (hnRNP A2/B1). However, what sets TDP-43 apart is the vast number of cases in which TDP-43 pathology is present, providing a point of convergence, the understanding of which could lead to broadly applicable therapeutics. Here we will focus on TDP-43 in ALS/FTLD, its nuclear and cytoplasmic functions, and consequences should these functions go awry.
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Affiliation(s)
- Marc Shenouda
- Tanz Centre for Research in Neurodegenerative Diseases and Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, M5T 2S8, Canada
| | - Ashley B Zhang
- Tanz Centre for Research in Neurodegenerative Diseases and Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, M5T 2S8, Canada
| | - Anna Weichert
- Tanz Centre for Research in Neurodegenerative Diseases and Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, M5T 2S8, Canada
| | - Janice Robertson
- Tanz Centre for Research in Neurodegenerative Diseases and Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, M5T 2S8, Canada.
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18
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Appocher C, Mohagheghi F, Cappelli S, Stuani C, Romano M, Feiguin F, Buratti E. Major hnRNP proteins act as general TDP-43 functional modifiers both in Drosophila and human neuronal cells. Nucleic Acids Res 2017; 45:8026-8045. [PMID: 28575377 PMCID: PMC5570092 DOI: 10.1093/nar/gkx477] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 05/16/2017] [Indexed: 12/13/2022] Open
Abstract
Nuclear factor TDP-43 is known to play an important role in several neurodegenerative pathologies. In general, TDP-43 is an abundant protein within the eukaryotic nucleus that binds to many coding and non-coding RNAs and influence their processing. Using Drosophila, we have performed a functional screening to establish the ability of major hnRNP proteins to affect TDP-43 overexpression/depletion phenotypes. Interestingly, we observed that lowering hnRNP and TDP-43 expression has a generally harmful effect on flies locomotor abilities. In parallel, our study has also identified a distinct set of hnRNPs that is capable of powerfully rescuing TDP-43 toxicity in the fly eye (Hrb27c, CG42458, Glo and Syp). Most importantly, removing the human orthologs of Hrb27c (DAZAP1) in human neuronal cell lines can correct several pre-mRNA splicing events altered by TDP-43 depletion. Moreover, using RNA sequencing analysis we show that DAZAP1 and TDP-43 can co-regulate an extensive number of biological processes and molecular functions potentially important for the neuron/motor neuron pathophysiology. Our results suggest that changes in hnRNP expression levels can significantly modulate TDP-43 functions and affect pathological outcomes.
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Affiliation(s)
- Chiara Appocher
- International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy
| | - Fatemeh Mohagheghi
- International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy
| | - Sara Cappelli
- International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy
| | - Cristiana Stuani
- International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy
| | - Maurizio Romano
- Department of Life Sciences, University of Trieste, Via A. Valerio 28, 34127 Trieste, Italy
| | - Fabian Feiguin
- International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy
| | - Emanuele Buratti
- International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy
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19
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Coyne AN, Zaepfel BL, Zarnescu DC. Failure to Deliver and Translate-New Insights into RNA Dysregulation in ALS. Front Cell Neurosci 2017; 11:243. [PMID: 28860970 PMCID: PMC5562674 DOI: 10.3389/fncel.2017.00243] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 07/31/2017] [Indexed: 12/12/2022] Open
Abstract
Amyotrophic Lateral Sclerosis (ALS) is a progressive and fatal neurodegenerative disease affecting both upper and lower motor neurons. The molecular mechanisms underlying disease pathogenesis remain largely unknown. Multiple genetic loci including genes involved in proteostasis and ribostasis have been linked to ALS providing key insights into the molecular mechanisms underlying disease. In particular, the identification of the RNA binding proteins TDP-43 and fused in sarcoma (FUS) as causative factors of ALS resulted in a paradigm shift centered on the study of RNA dysregulation as a major mechanism of disease. With wild-type TDP-43 pathology being found in ~97% of ALS cases and the identification of disease causing mutations within its sequence, TDP-43 has emerged as a prominent player in ALS. More recently, studies of the newly discovered C9orf72 repeat expansion are lending further support to the notion of defects in RNA metabolism as a key factor underlying ALS. RNA binding proteins are involved in all aspects of RNA metabolism ranging from splicing, transcription, transport, storage into RNA/protein granules, and translation. How these processes are affected by disease-associated mutations is just beginning to be understood. Considerable work has gone into the identification of splicing and transcription defects resulting from mutations in RNA binding proteins associated with disease. More recently, defects in RNA transport and translation have been shown to be involved in the pathomechanism of ALS. A central hypothesis in the field is that disease causing mutations lead to the persistence of RNA/protein complexes known as stress granules. Under times of prolonged cellular stress these granules sequester specific mRNAs preventing them from translation, and are thought to evolve into pathological aggregates. Here we will review recent efforts directed at understanding how altered RNA metabolism contributes to ALS pathogenesis.
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Affiliation(s)
- Alyssa N Coyne
- Department of Molecular and Cellular Biology, University of ArizonaTucson, AZ, United States.,Department of Neuroscience, University of ArizonaTucson, AZ, United States
| | - Benjamin L Zaepfel
- Department of Molecular and Cellular Biology, University of ArizonaTucson, AZ, United States
| | - Daniela C Zarnescu
- Department of Molecular and Cellular Biology, University of ArizonaTucson, AZ, United States.,Department of Neuroscience, University of ArizonaTucson, AZ, United States.,Department of Neurology, University of ArizonaTucson, AZ, United States
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20
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Budini M, Buratti E, Morselli E, Criollo A. Autophagy and Its Impact on Neurodegenerative Diseases: New Roles for TDP-43 and C9orf72. Front Mol Neurosci 2017; 10:170. [PMID: 28611593 PMCID: PMC5447761 DOI: 10.3389/fnmol.2017.00170] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 05/15/2017] [Indexed: 12/12/2022] Open
Abstract
Autophagy is a catabolic mechanism where intracellular material is degraded by vesicular structures called autophagolysosomes. Autophagy is necessary to maintain the normal function of the central nervous system (CNS), avoiding the accumulation of misfolded and aggregated proteins. Consistently, impaired autophagy has been associated with the pathogenesis of various neurodegenerative diseases. The proteins TAR DNA-binding protein-43 (TDP-43), which regulates RNA processing at different levels, and chromosome 9 open reading frame 72 (C9orf72), probably involved in membrane trafficking, are crucial in the development of neurodegenerative diseases such as Amyotrophic lateral sclerosis (ALS) and Frontotemporal Lobar Degeneration (FTLD). Additionally, recent studies have identified a role for these proteins in the control of autophagy. In this manuscript, we review what is known regarding the autophagic mechanism and discuss the involvement of TDP-43 and C9orf72 in autophagy and their impact on neurodegenerative diseases.
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Affiliation(s)
- Mauricio Budini
- Dentistry Faculty, Institute in Dentistry Sciences, University of ChileSantiago, Chile
| | - Emanuele Buratti
- International Centre for Genetic Engineering and BiotechnologyTrieste, Italy
| | - Eugenia Morselli
- Department of Physiology, Faculty of Biological Sciences, Pontificia Universidad Católica de ChileSantiago, Chile
| | - Alfredo Criollo
- Dentistry Faculty, Institute in Dentistry Sciences, University of ChileSantiago, Chile.,Advanced Center for Chronic DiseasesSantiago, Chile
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21
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Peled S, Sade D, Bram Y, Porat Z, Kreiser T, Mimouni M, Lichtenstein A, Segal D, Gazit E. Single cell imaging and quantification of TDP-43 and α-synuclein intercellular propagation. Sci Rep 2017; 7:544. [PMID: 28373710 PMCID: PMC5428807 DOI: 10.1038/s41598-017-00657-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Accepted: 03/07/2017] [Indexed: 12/12/2022] Open
Abstract
The intercellular spreading of protein assemblies is a major factor in the progression of neurodegenerative disorders. The quantitative study and visualization of cell-to-cell propagation using tagged-proteins is challenging due to the steric effect of relatively large fluorescence tags and the risk of 'false positive' identification when analyzing these rare transmission events. Here, we established a cell culture model to characterize the cell-to-cell transmission of TAR DNA-binding protein and α-synuclein, involved in amyotrophic lateral sclerosis and Parkinson's disease, respectively, using the small nine amino acid influenza hemagglutinin tag. The novel use of single cell resolution imaging flow cytometry allowed the visualization and quantification of all individual transmission events. Cell-level analysis of these events indicated that the degree of transfer is lower than previously reported based on conventional flow cytometry. Furthermore, our analysis can exclude 'false positive' events of cellular overlap and extracellular debris attachment. The results were corroborated by high-resolution confocal microscopy mapping of protein localization.
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Affiliation(s)
- Sivan Peled
- Department of Molecular Microbiology and Biotechnology, Tel-Aviv University, Tel Aviv, 6997801, Israel
| | - Dorin Sade
- Department of Molecular Microbiology and Biotechnology, Tel-Aviv University, Tel Aviv, 6997801, Israel
| | - Yaron Bram
- Department of Molecular Microbiology and Biotechnology, Tel-Aviv University, Tel Aviv, 6997801, Israel
- Division of Gastroenterology & Hepatology, Department of Medicine, Weill Medical College of Cornell University, New York, NY, 10021, USA
| | - Ziv Porat
- Flow Cytometry Unit, Department of Biological Services, Weizmann Institute of Science, Rehovot, Israel
| | - Topaz Kreiser
- Department of Molecular Microbiology and Biotechnology, Tel-Aviv University, Tel Aviv, 6997801, Israel
| | - Michael Mimouni
- Department of Ophthalmology, Rambam Health Care Campus, Haifa, Israel
| | - Alexandra Lichtenstein
- Sackler Cellular and Molecular Imaging Center, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel
| | - Daniel Segal
- Department of Molecular Microbiology and Biotechnology, Tel-Aviv University, Tel Aviv, 6997801, Israel
- Sagol Interdisciplinary School of Neurosciences, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Ehud Gazit
- Department of Molecular Microbiology and Biotechnology, Tel-Aviv University, Tel Aviv, 6997801, Israel.
- Sagol Interdisciplinary School of Neurosciences, Tel Aviv University, Tel Aviv, 6997801, Israel.
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22
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Affiliation(s)
- Chung-Ke Chang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Tai-Huang Huang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
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24
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Buratti E. Functional Significance of TDP-43 Mutations in Disease. ADVANCES IN GENETICS 2015; 91:1-53. [DOI: 10.1016/bs.adgen.2015.07.001] [Citation(s) in RCA: 133] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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