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Sellier C, Corcia P, Vourc'h P, Dupuis L. C9ORF72 hexanucleotide repeat expansion: From ALS and FTD to a broader pathogenic role? Rev Neurol (Paris) 2024; 180:417-428. [PMID: 38609750 DOI: 10.1016/j.neurol.2024.03.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Accepted: 03/30/2024] [Indexed: 04/14/2024]
Abstract
The major gene underlying monogenic forms of amyotrophic lateral sclerosis (ALS) and fronto-temporal dementia (FTD) is C9ORF72. The causative mutation in C9ORF72 is an abnormal hexanucleotide (G4C2) repeat expansion (HRE) located in the first intron of the gene. The aim of this review is to propose a comprehensive update on recent developments on clinical, biological and therapeutics aspects related to C9ORF72 in order to highlight the current understanding of genotype-phenotype correlations, and also on biological machinery leading to neuronal death. We will particularly focus on the broad phenotypic presentation of C9ORF72-related diseases, that goes well beyond the classical phenotypes observed in ALS and FTD patients. Last, we will comment the possible therapeutical hopes for patients carrying a C9ORF72 HRE.
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Affiliation(s)
- C Sellier
- Centre de recherches en biomédecine de Strasbourg, UMR-S1329, Inserm, université de Strasbourg, Strasbourg, France
| | - P Corcia
- UMR 1253 iBrain, Inserm, université de Tours, Tours, France; Centre constitutif de coordination SLA, CHU de Bretonneau, 2, boulevard Tonnelle, 37044 Tours cedex 1, France
| | - P Vourc'h
- UMR 1253 iBrain, Inserm, université de Tours, Tours, France; Service de biochimie et biologie moléculaire, CHU de Tours, Tours, France
| | - L Dupuis
- Centre de recherches en biomédecine de Strasbourg, UMR-S1329, Inserm, université de Strasbourg, Strasbourg, France.
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2
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Sachdev A, Gill K, Sckaff M, Birk AM, Aladesuyi Arogundade O, Brown KA, Chouhan RS, Issagholian-Lewin PO, Patel E, Watry HL, Bernardi MT, Keough KC, Tsai YC, Smith AST, Conklin BR, Clelland CD. Reversal of C9orf72 mutation-induced transcriptional dysregulation and pathology in cultured human neurons by allele-specific excision. Proc Natl Acad Sci U S A 2024; 121:e2307814121. [PMID: 38621131 PMCID: PMC11047104 DOI: 10.1073/pnas.2307814121] [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: 05/09/2023] [Accepted: 03/01/2024] [Indexed: 04/17/2024] Open
Abstract
Efforts to genetically reverse C9orf72 pathology have been hampered by our incomplete understanding of the regulation of this complex locus. We generated five different genomic excisions at the C9orf72 locus in a patient-derived induced pluripotent stem cell (iPSC) line and a non-diseased wild-type (WT) line (11 total isogenic lines), and examined gene expression and pathological hallmarks of C9 frontotemporal dementia/amyotrophic lateral sclerosis in motor neurons differentiated from these lines. Comparing the excisions in these isogenic series removed the confounding effects of different genomic backgrounds and allowed us to probe the effects of specific genomic changes. A coding single nucleotide polymorphism in the patient cell line allowed us to distinguish transcripts from the normal vs. mutant allele. Using digital droplet PCR (ddPCR), we determined that transcription from the mutant allele is upregulated at least 10-fold, and that sense transcription is independently regulated from each allele. Surprisingly, excision of the WT allele increased pathologic dipeptide repeat poly-GP expression from the mutant allele. Importantly, a single allele was sufficient to supply a normal amount of protein, suggesting that the C9orf72 gene is haplo-sufficient in induced motor neurons. Excision of the mutant repeat expansion reverted all pathology (RNA abnormalities, dipeptide repeat production, and TDP-43 pathology) and improved electrophysiological function, whereas silencing sense expression did not eliminate all dipeptide repeat proteins, presumably because of the antisense expression. These data increase our understanding of C9orf72 gene regulation and inform gene therapy approaches, including antisense oligonucleotides (ASOs) and CRISPR gene editing.
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Affiliation(s)
| | - Kamaljot Gill
- Gladstone Institutes, San Francisco, CA94158
- Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA94158
| | - Maria Sckaff
- Gladstone Institutes, San Francisco, CA94158
- Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA94158
| | | | - Olubankole Aladesuyi Arogundade
- Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA94158
- Memory & Aging Center, Department of Neurology, University of California San Francisco, San Francisco, CA94158
| | - Katherine A. Brown
- Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA94158
- Memory & Aging Center, Department of Neurology, University of California San Francisco, San Francisco, CA94158
| | - Runvir S. Chouhan
- Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA94158
- Memory & Aging Center, Department of Neurology, University of California San Francisco, San Francisco, CA94158
| | - Patrick Oliver Issagholian-Lewin
- Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA94158
- Memory & Aging Center, Department of Neurology, University of California San Francisco, San Francisco, CA94158
| | - Esha Patel
- Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA94158
- Memory & Aging Center, Department of Neurology, University of California San Francisco, San Francisco, CA94158
| | | | | | | | | | - Alec Simon Tulloch Smith
- Department of Physiology and Biophysics, University of Washington, Seattle, WA98195
- The Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA98195
| | - Bruce R. Conklin
- Gladstone Institutes, San Francisco, CA94158
- Department of Medicine, University of California San Francisco, San Francisco, CA94143
- Department of Ophthalmology, University of California San Francisco, San Francisco, CA94143
- Department of Pharmacology, University of California San Francisco, San Francisco, CA94158
| | - Claire Dudley Clelland
- Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA94158
- Memory & Aging Center, Department of Neurology, University of California San Francisco, San Francisco, CA94158
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3
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Chen S, Cai X, Lao L, Wang Y, Su H, Sun H. Brain-Gut-Microbiota Axis in Amyotrophic Lateral Sclerosis: A Historical Overview and Future Directions. Aging Dis 2024; 15:74-95. [PMID: 37307822 PMCID: PMC10796086 DOI: 10.14336/ad.2023.0524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Accepted: 05/24/2023] [Indexed: 06/14/2023] Open
Abstract
Amyotrophic Lateral Sclerosis (ALS) is a devastating neurodegenerative disease which is strongly associated with age. The incidence of ALS increases from the age of 40 and peaks between the ages of 65 and 70. Most patients die of respiratory muscle paralysis or lung infections within three to five years of the appearance of symptoms, dealing a huge blow to patients and their families. With aging populations, improved diagnostic methods and changes in reporting criteria, the incidence of ALS is likely to show an upward trend in the coming decades. Despite extensive researches have been done, the cause and pathogenesis of ALS remains unclear. In recent decades, large quantities of studies focusing on gut microbiota have shown that gut microbiota and its metabolites seem to change the evolvement of ALS through the brain-gut-microbiota axis, and in turn, the progression of ALS will exacerbate the imbalance of gut microbiota, thereby forming a vicious cycle. This suggests that further exploration and identification of the function of gut microbiota in ALS may be crucial to break the bottleneck in the diagnosis and treatment of this disease. Hence, the current review summarizes and discusses the latest research advancement and future directions of ALS and brain-gut-microbiota axis, so as to help relevant researchers gain correlative information instantly.
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Affiliation(s)
- Shilan Chen
- Clinical Biobank Center, Microbiome Medicine Center, Department of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou 510280, China.
- Neurosurgery Center, The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China on Diagnosis and Treatment of Cerebrovascular Disease, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, The Neurosurgery Institute of Guangdong Province, Zhujiang Hospital, Southern Medical University, Guangzhou 510280, China.
| | - Xinhong Cai
- Clinical Biobank Center, Microbiome Medicine Center, Department of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou 510280, China.
- Neurosurgery Center, The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China on Diagnosis and Treatment of Cerebrovascular Disease, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, The Neurosurgery Institute of Guangdong Province, Zhujiang Hospital, Southern Medical University, Guangzhou 510280, China.
| | - Lin Lao
- Clinical Biobank Center, Microbiome Medicine Center, Department of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou 510280, China.
- Neurosurgery Center, The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China on Diagnosis and Treatment of Cerebrovascular Disease, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, The Neurosurgery Institute of Guangdong Province, Zhujiang Hospital, Southern Medical University, Guangzhou 510280, China.
| | - Yuxuan Wang
- Clinical Biobank Center, Microbiome Medicine Center, Department of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou 510280, China.
- Neurosurgery Center, The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China on Diagnosis and Treatment of Cerebrovascular Disease, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, The Neurosurgery Institute of Guangdong Province, Zhujiang Hospital, Southern Medical University, Guangzhou 510280, China.
| | - Huanxing Su
- Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Taipa, Macau.
| | - Haitao Sun
- Clinical Biobank Center, Microbiome Medicine Center, Department of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou 510280, China.
- Neurosurgery Center, The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China on Diagnosis and Treatment of Cerebrovascular Disease, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, The Neurosurgery Institute of Guangdong Province, Zhujiang Hospital, Southern Medical University, Guangzhou 510280, China.
- Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Southern Medical University, Guangzhou, China.
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4
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Parameswaran J, Zhang N, Braems E, Tilahun K, Pant DC, Yin K, Asress S, Heeren K, Banerjee A, Davis E, Schwartz SL, Conn GL, Bassell GJ, Van Den Bosch L, Jiang J. Antisense, but not sense, repeat expanded RNAs activate PKR/eIF2α-dependent ISR in C9ORF72 FTD/ALS. eLife 2023; 12:e85902. [PMID: 37073950 PMCID: PMC10188109 DOI: 10.7554/elife.85902] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Accepted: 04/18/2023] [Indexed: 04/20/2023] Open
Abstract
GGGGCC (G4C2) hexanucleotide repeat expansion in the C9ORF72 gene is the most common genetic cause of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). The repeat is bidirectionally transcribed and confers gain of toxicity. However, the underlying toxic species is debated, and it is not clear whether antisense CCCCGG (C4G2) repeat expanded RNAs contribute to disease pathogenesis. Our study shows that C9ORF72 antisense C4G2 repeat expanded RNAs trigger the activation of the PKR/eIF2α-dependent integrated stress response independent of dipeptide repeat proteins that are produced through repeat-associated non-AUG-initiated translation, leading to global translation inhibition and stress granule formation. Reducing PKR levels with either siRNA or morpholinos mitigates integrated stress response and toxicity caused by the antisense C4G2 RNAs in cell lines, primary neurons, and zebrafish. Increased phosphorylation of PKR/eIF2α is also observed in the frontal cortex of C9ORF72 FTD/ALS patients. Finally, only antisense C4G2, but not sense G4C2, repeat expanded RNAs robustly activate the PKR/eIF2α pathway and induce aberrant stress granule formation. These results provide a mechanism by which antisense C4G2 repeat expanded RNAs elicit neuronal toxicity in FTD/ALS caused by C9ORF72 repeat expansions.
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Affiliation(s)
| | - Nancy Zhang
- Department of Cell Biology, Emory UniversityAtlantaUnited States
| | - Elke Braems
- Department of Neurosciences, Experimental Neurology and Leuven Brain Institute, KU LeuvenLeuvenBelgium
- Center for Brain & Disease Research, Laboratory of Neurobiology, VIB, Campus GasthuisbergLeuvenBelgium
| | | | - Devesh C Pant
- Department of Cell Biology, Emory UniversityAtlantaUnited States
| | - Keena Yin
- Department of Cell Biology, Emory UniversityAtlantaUnited States
| | - Seneshaw Asress
- Department of Neurology, Emory UniversityAtlantaUnited States
| | - Kara Heeren
- Department of Neurosciences, Experimental Neurology and Leuven Brain Institute, KU LeuvenLeuvenBelgium
- Center for Brain & Disease Research, Laboratory of Neurobiology, VIB, Campus GasthuisbergLeuvenBelgium
| | - Anwesha Banerjee
- Department of Cell Biology, Emory UniversityAtlantaUnited States
| | - Emma Davis
- Department of Cell Biology, Emory UniversityAtlantaUnited States
| | | | - Graeme L Conn
- Department of Biochemistry, Emory UniversityAtlantaUnited States
| | - Gary J Bassell
- Department of Cell Biology, Emory UniversityAtlantaUnited States
| | - Ludo Van Den Bosch
- Department of Neurosciences, Experimental Neurology and Leuven Brain Institute, KU LeuvenLeuvenBelgium
- Center for Brain & Disease Research, Laboratory of Neurobiology, VIB, Campus GasthuisbergLeuvenBelgium
| | - Jie Jiang
- Department of Cell Biology, Emory UniversityAtlantaUnited States
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Teng Y, Zhu M, Qiu Z. G-Quadruplexes in Repeat Expansion Disorders. Int J Mol Sci 2023; 24:ijms24032375. [PMID: 36768697 PMCID: PMC9916761 DOI: 10.3390/ijms24032375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 01/19/2023] [Accepted: 01/23/2023] [Indexed: 01/27/2023] Open
Abstract
The repeat expansions are the main genetic cause of various neurodegeneration diseases. More than ten kinds of repeat sequences with different lengths, locations, and structures have been confirmed in the past two decades. G-rich repeat sequences, such as CGG and GGGGCC, are reported to form functional G-quadruplexes, participating in many important bioprocesses. In this review, we conducted an overview concerning the contribution of G-quadruplex in repeat expansion disorders and summarized related mechanisms in current pathological studies, including the increasing genetic instabilities in replication and transcription, the toxic RNA foci formed in neurons, and the loss/gain function of proteins and peptides. Furthermore, novel strategies targeting G-quadruplex repeats were developed based on the understanding of disease mechanism. Small molecules and proteins binding to G-quadruplex in repeat expansions were investigated to protect neurons from dysfunction and delay the progression of neurodegeneration. In addition, the effects of environment on the stability of G-quadruplex were discussed, which might be critical factors in the pathological study of repeat expansion disorders.
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6
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Meanti R, Bresciani E, Rizzi L, Coco S, Zambelli V, Dimitroulas A, Molteni L, Omeljaniuk RJ, Locatelli V, Torsello A. Potential Applications for Growth Hormone Secretagogues Treatment of Amyotrophic Lateral Sclerosis. Curr Neuropharmacol 2023; 21:2376-2394. [PMID: 36111771 PMCID: PMC10616926 DOI: 10.2174/1570159x20666220915103613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 07/18/2022] [Accepted: 08/01/2022] [Indexed: 11/22/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) arises from neuronal death due to complex interactions of genetic, molecular, and environmental factors. Currently, only two drugs, riluzole and edaravone, have been approved to slow the progression of this disease. However, ghrelin and other ligands of the GHS-R1a receptor have demonstrated interesting neuroprotective activities that could be exploited in this pathology. Ghrelin, a 28-amino acid hormone, primarily synthesized and secreted by oxyntic cells in the stomach wall, binds to the pituitary GHS-R1a and stimulates GH secretion; in addition, ghrelin is endowed with multiple extra endocrine bioactivities. Native ghrelin requires esterification with octanoic acid for binding to the GHS-R1a receptor; however, this esterified form is very labile and represents less than 10% of circulating ghrelin. A large number of synthetic compounds, the growth hormone secretagogues (GHS) encompassing short peptides, peptoids, and non-peptidic moieties, are capable of mimicking several biological activities of ghrelin, including stimulation of GH release, appetite, and elevation of blood IGF-I levels. GHS have demonstrated neuroprotective and anticonvulsant effects in experimental models of pathologies both in vitro and in vivo. To illustrate, some GHS, currently under evaluation by regulatory agencies for the treatment of human cachexia, have a good safety profile and are safe for human use. Collectively, evidence suggests that ghrelin and cognate GHS may constitute potential therapies for ALS.
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Affiliation(s)
- Ramona Meanti
- School of Medicine and Surgery, University of Milano-Bicocca, Via Cadore 48, Monza, 20900, Italy
| | - Elena Bresciani
- School of Medicine and Surgery, University of Milano-Bicocca, Via Cadore 48, Monza, 20900, Italy
| | - Laura Rizzi
- School of Medicine and Surgery, University of Milano-Bicocca, Via Cadore 48, Monza, 20900, Italy
| | - Silvia Coco
- School of Medicine and Surgery, University of Milano-Bicocca, Via Cadore 48, Monza, 20900, Italy
| | - Vanessa Zambelli
- School of Medicine and Surgery, University of Milano-Bicocca, Via Cadore 48, Monza, 20900, Italy
| | - Anna Dimitroulas
- Faculty of Health and Medical Sciences, University of Surrey, Stag Hill, Guildford, GU2 7XH, United Kingdom
| | - Laura Molteni
- School of Medicine and Surgery, University of Milano-Bicocca, Via Cadore 48, Monza, 20900, Italy
| | - Robert J. Omeljaniuk
- Department of Biology, Lakehead University, 955 Oliver Rd, Thunder Bay, Ontario, P7B 5E1, Canada
| | - Vittorio Locatelli
- School of Medicine and Surgery, University of Milano-Bicocca, Via Cadore 48, Monza, 20900, Italy
| | - Antonio Torsello
- School of Medicine and Surgery, University of Milano-Bicocca, Via Cadore 48, Monza, 20900, Italy
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7
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Smeyers J, Banchi EG, Latouche M. C9ORF72: What It Is, What It Does, and Why It Matters. Front Cell Neurosci 2021; 15:661447. [PMID: 34025358 PMCID: PMC8131521 DOI: 10.3389/fncel.2021.661447] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Accepted: 03/17/2021] [Indexed: 12/11/2022] Open
Abstract
When the non-coding repeat expansion in the C9ORF72 gene was discovered to be the most frequent cause of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) in 2011, this gene and its derived protein, C9ORF72, were completely unknown. The mutation appeared to produce both haploinsufficiency and gain-of-function effects in the form of aggregating expanded RNAs and dipeptide repeat proteins (DPRs). An unprecedented effort was then unleashed to decipher the pathogenic mechanisms and the functions of C9ORF72 in order to design therapies. A decade later, while the toxicity of accumulating gain-of-function products has been established and therapeutic strategies are being developed to target it, the contribution of the loss of function starts to appear more clearly. This article reviews the current knowledge about the C9ORF72 protein, how it is affected by the repeat expansion in models and patients, and what could be the contribution of its haploinsufficiency to the disease in light of the most recent findings. We suggest that these elements should be taken into consideration to refine future therapeutic strategies, compensating for the decrease of C9ORF72 or at least preventing a further reduction.
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Affiliation(s)
- Julie Smeyers
- Sorbonne Université, Institut du Cerveau - Paris Brain Institute - ICM, Inserm, CNRS, APHP, Hôpital de la Pitié Salpêtrière, DMU Neuroscience 6, Paris, France
- PSL Research university, EPHE, Neurogenetics team, Paris, France
| | - Elena-Gaia Banchi
- Sorbonne Université, Institut du Cerveau - Paris Brain Institute - ICM, Inserm, CNRS, APHP, Hôpital de la Pitié Salpêtrière, DMU Neuroscience 6, Paris, France
| | - Morwena Latouche
- Sorbonne Université, Institut du Cerveau - Paris Brain Institute - ICM, Inserm, CNRS, APHP, Hôpital de la Pitié Salpêtrière, DMU Neuroscience 6, Paris, France
- PSL Research university, EPHE, Neurogenetics team, Paris, France
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8
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Gagliardi D, Costamagna G, Taiana M, Andreoli L, Biella F, Bersani M, Bresolin N, Comi GP, Corti S. Insights into disease mechanisms and potential therapeutics for C9orf72-related amyotrophic lateral sclerosis/frontotemporal dementia. Ageing Res Rev 2020; 64:101172. [PMID: 32971256 DOI: 10.1016/j.arr.2020.101172] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 08/31/2020] [Indexed: 12/12/2022]
Abstract
In 2011, a hexanucleotide repeat expansion (HRE) in the noncoding region of C9orf72 was associated with the most frequent genetic cause of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). The main pathogenic mechanisms in C9-ALS/FTD are haploinsufficiency of the C9orf72 protein and gain of function toxicity from bidirectionally-transcribed repeat-containing RNAs and dipeptide repeat proteins (DPRs) resulting from non-canonical RNA translation. Additionally, abnormalities in different downstream cellular mechanisms, such as nucleocytoplasmic transport and autophagy, play a role in pathogenesis. Substantial research efforts using in vitro and in vivo models have provided valuable insights into the contribution of each mechanism in disease pathogenesis. However, conflicting evidence exists, and a unifying theory still lacks. Here, we provide an overview of the recently published literature on clinical, neuropathological and molecular features of C9-ALS/FTD. We highlight the supposed neuronal role of C9orf72 and the HRE pathogenic cascade, mainly focusing on the contribution of RNA foci and DPRs to neurodegeneration and discussing the several downstream mechanisms. We summarize the emerging biochemical and neuroimaging biomarkers, as well as the potential therapeutic approaches. Despite promising results, a specific disease-modifying treatment is still not available to date and greater insights into disease mechanisms may help in this direction.
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Affiliation(s)
- Delia Gagliardi
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Via Francesco Sforza 35, 20122 Milan, Italy
| | - Gianluca Costamagna
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Via Francesco Sforza 35, 20122 Milan, Italy
| | - Michela Taiana
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Via Francesco Sforza 35, 20122 Milan, Italy
| | - Luca Andreoli
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Via Francesco Sforza 35, 20122 Milan, Italy
| | - Fabio Biella
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Via Francesco Sforza 35, 20122 Milan, Italy
| | - Margherita Bersani
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Via Francesco Sforza 35, 20122 Milan, Italy
| | - Nereo Bresolin
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Via Francesco Sforza 35, 20122 Milan, Italy; Neurology Unit, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, Via Francesco Sforza 35, 20122, Milan, Italy
| | - Giacomo Pietro Comi
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Via Francesco Sforza 35, 20122 Milan, Italy; Neurology Unit, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, Via Francesco Sforza 35, 20122, Milan, Italy
| | - Stefania Corti
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Via Francesco Sforza 35, 20122 Milan, Italy; Neurology Unit, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, Via Francesco Sforza 35, 20122, Milan, Italy.
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9
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Braems E, Swinnen B, Van Den Bosch L. C9orf72 loss-of-function: a trivial, stand-alone or additive mechanism in C9 ALS/FTD? Acta Neuropathol 2020; 140:625-643. [PMID: 32876811 PMCID: PMC7547039 DOI: 10.1007/s00401-020-02214-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Revised: 07/28/2020] [Accepted: 08/13/2020] [Indexed: 12/11/2022]
Abstract
A repeat expansion in C9orf72 is responsible for the characteristic neurodegeneration in amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) in a still unresolved manner. Proposed mechanisms involve gain-of-functions, comprising RNA and protein toxicity, and loss-of-function of the C9orf72 gene. Their exact contribution is still inconclusive and reports regarding loss-of-function are rather inconsistent. Here, we review the function of the C9orf72 protein and its relevance in disease. We explore the potential link between reduced C9orf72 levels and disease phenotypes in postmortem, in vitro, and in vivo models. Moreover, the significance of loss-of-function in other non-coding repeat expansion diseases is used to clarify its contribution in C9orf72 ALS/FTD. In conclusion, with evidence pointing to a multiple-hit model, loss-of-function on itself seems to be insufficient to cause neurodegeneration in C9orf72 ALS/FTD.
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Affiliation(s)
- Elke Braems
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute (LBI), KU Leuven-University of Leuven, 3000, Leuven, Belgium
- Laboratory of Neurobiology, Experimental Neurology, Center for Brain and Disease Research, VIB, Campus Gasthuisberg, O&N4, Herestraat 49, PB 602, 3000, Leuven, Belgium
| | - Bart Swinnen
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute (LBI), KU Leuven-University of Leuven, 3000, Leuven, Belgium
- Laboratory of Neurobiology, Experimental Neurology, Center for Brain and Disease Research, VIB, Campus Gasthuisberg, O&N4, Herestraat 49, PB 602, 3000, Leuven, Belgium
- Department of Neurology, University Hospitals Leuven, 3000, Leuven, Belgium
| | - Ludo Van Den Bosch
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute (LBI), KU Leuven-University of Leuven, 3000, Leuven, Belgium.
- Laboratory of Neurobiology, Experimental Neurology, Center for Brain and Disease Research, VIB, Campus Gasthuisberg, O&N4, Herestraat 49, PB 602, 3000, Leuven, Belgium.
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10
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Martier R, Konstantinova P. Gene Therapy for Neurodegenerative Diseases: Slowing Down the Ticking Clock. Front Neurosci 2020; 14:580179. [PMID: 33071748 PMCID: PMC7530328 DOI: 10.3389/fnins.2020.580179] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Accepted: 08/31/2020] [Indexed: 12/13/2022] Open
Abstract
Gene therapy is an emerging and powerful therapeutic tool to deliver functional genetic material to cells in order to correct a defective gene. During the past decades, several studies have demonstrated the potential of AAV-based gene therapies for the treatment of neurodegenerative diseases. While some clinical studies have failed to demonstrate therapeutic efficacy, the use of AAV as a delivery tool has demonstrated to be safe. Here, we discuss the past, current and future perspectives of gene therapies for neurodegenerative diseases. We also discuss the current advances on the newly emerging RNAi-based gene therapies which has been widely studied in preclinical model and recently also made it to the clinic.
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Affiliation(s)
- Raygene Martier
- Department of Research and Development, uniQure Biopharma B.V., Amsterdam, Netherlands
| | - Pavlina Konstantinova
- Department of Research and Development, uniQure Biopharma B.V., Amsterdam, Netherlands
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11
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McEachin ZT, Parameswaran J, Raj N, Bassell GJ, Jiang J. RNA-mediated toxicity in C9orf72 ALS and FTD. Neurobiol Dis 2020; 145:105055. [PMID: 32829028 DOI: 10.1016/j.nbd.2020.105055] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 07/27/2020] [Accepted: 08/18/2020] [Indexed: 12/13/2022] Open
Abstract
A GGGGCC hexanucleotide repeat expansion in the first intron of C9orf72 is the most common genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia. Compelling evidence suggests that gain of toxicity from the bidirectionally transcribed repeat expanded RNAs plays a central role in disease pathogenesis. Two potential mechanisms have been proposed including RNA-mediated toxicity and/or the production of toxic dipeptide repeat proteins. In this review, we focus on the role of RNA mediated toxicity in ALS/FTD caused by the C9orf72 mutation and discuss arguments for and against this mechanism. In addition, we summarize how G4C2 repeat RNAs can elicit toxicity and potential therapeutic strategies to mitigate RNA-mediated toxicity.
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Affiliation(s)
- Zachary T McEachin
- Department of Cell Biology, Emory University, Atlanta, GA 30322, USA; Laboratory for Translational Cell Biology, Emory University, Atlanta, GA 30322, USA.
| | | | - Nisha Raj
- Department of Cell Biology, Emory University, Atlanta, GA 30322, USA; Laboratory for Translational Cell Biology, Emory University, Atlanta, GA 30322, USA
| | - Gary J Bassell
- Department of Cell Biology, Emory University, Atlanta, GA 30322, USA; Laboratory for Translational Cell Biology, Emory University, Atlanta, GA 30322, USA; Department of Neurology, Emory University, Atlanta, GA 30322, USA
| | - Jie Jiang
- Department of Cell Biology, Emory University, Atlanta, GA 30322, USA.
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12
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Mystery of Expansion: DNA Metabolism and Unstable Repeats. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1241:101-124. [PMID: 32383118 DOI: 10.1007/978-3-030-41283-8_7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
The mammalian genome mostly contains repeated sequences. Some of these repeats are in the regulatory elements of genes, and their instability, particularly the propensity to change the repeat unit number, is responsible for 36 well-known neurodegenerative human disorders. The mechanism of repeat expansion has been an unsolved question for more than 20 years. There are a few hypotheses describing models of mutation development. Every hypothesis is based on assumptions about unusual secondary structures that violate DNA metabolism processes in the cell. Some models are based on replication errors, and other models are based on mismatch repair or base excision repair errors. Additionally, it has been shown that epigenetic regulation of gene expression can influence the probability and frequency of expansion. In this review, we consider the molecular bases of repeat expansion disorders and discuss possible mechanisms of repeat expansion during cell metabolism.
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13
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Goodier JL, Soares AO, Pereira GC, DeVine LR, Sanchez L, Cole RN, García-Pérez JL. C9orf72-associated SMCR8 protein binds in the ubiquitin pathway and with proteins linked with neurological disease. Acta Neuropathol Commun 2020; 8:110. [PMID: 32678027 PMCID: PMC7364817 DOI: 10.1186/s40478-020-00982-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 06/26/2020] [Indexed: 02/08/2023] Open
Abstract
A pathogenic GGGCCC hexanucleotide expansion in the first intron/promoter region of the C9orf72 gene is the most common mutation associated with amyotrophic lateral sclerosis (ALS). The C9orf72 gene product forms a complex with SMCR8 (Smith-Magenis Syndrome Chromosome Region, Candidate 8) and WDR41 (WD Repeat domain 41) proteins. Recent studies have indicated roles for the complex in autophagy regulation, vesicle trafficking, and immune response in transgenic mice, however a direct connection with ALS etiology remains unclear. With the aim of increasing understanding of the multi-functional C9orf72-SMCR8-WDR41 complex, we determined by mass spectrometry analysis the proteins that directly associate with SMCR8. SMCR8 protein binds many components of the ubiquitin-proteasome system, and we demonstrate its poly-ubiquitination without obvious degradation. Evidence is also presented for localization of endogenous SMCR8 protein to cytoplasmic stress granules. However, in several cell lines we failed to reproduce previous observations that C9orf72 protein enters these granules. SMCR8 protein associates with many products of genes associated with various Mendelian neurological disorders in addition to ALS, implicating SMCR8-containing complexes in a range of neuropathologies. We reinforce previous observations that SMCR8 and C9orf72 protein levels are positively linked, and now show in vivo that SMCR8 protein levels are greatly reduced in brain tissues of C9orf72 gene expansion carrier individuals. While further study is required, these data suggest that SMCR8 protein level might prove a useful biomarker for the C9orf72 expansion in ALS.
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Affiliation(s)
- John L. Goodier
- McKusick-Nathans Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD USA
| | - Alisha O. Soares
- McKusick-Nathans Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD USA
| | - Gavin C. Pereira
- McKusick-Nathans Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD USA
| | - Lauren R. DeVine
- Mass Spectrometry and Proteomics Facility, Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD USA
| | - Laura Sanchez
- GENYO. Centre for Genomics and Oncological Research: Pfizer, University of Granada, Andalusian Regional Government, Granada, Spain
| | - Robert N. Cole
- Mass Spectrometry and Proteomics Facility, Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD USA
| | - Jose Luis García-Pérez
- GENYO. Centre for Genomics and Oncological Research: Pfizer, University of Granada, Andalusian Regional Government, Granada, Spain
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine (IGMM), University of Edinburgh, Western General Hospital, Edinburgh, UK
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14
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Porterfield V, Khan SS, Foff EP, Koseoglu MM, Blanco IK, Jayaraman S, Lien E, McConnell MJ, Bloom GS, Lazo JS, Sharlow ER. A three-dimensional dementia model reveals spontaneous cell cycle re-entry and a senescence-associated secretory phenotype. Neurobiol Aging 2020; 90:125-134. [PMID: 32184029 DOI: 10.1016/j.neurobiolaging.2020.02.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 01/31/2020] [Accepted: 02/12/2020] [Indexed: 12/12/2022]
Abstract
A hexanucleotide repeat expansion on chromosome 9 open reading frame 72 (C9orf72) is associated with familial amyotrophic lateral sclerosis (ALS) and a subpopulation of patients with sporadic ALS and frontotemporal dementia. We used inducible pluripotent stem cells from neurotypic and C9orf72+ (C9+) ALS patients to derive neuronal progenitor cells. We demonstrated that C9+ and neurotypic neuronal progenitor cells differentiate into neurons. The C9+ neurons, however, spontaneously re-expressed cyclin D1 after 12 weeks, suggesting cell cycle re-engagement. Gene profiling revealed significant increases in senescence-associated genes in C9+ neurons. Moreover, C9+ neurons expressed high levels of mRNA for CXCL8, a chemokine overexpressed by senescent cells, while media from C9+ neurons contained significant levels of CXCL8, CXCL1, IL13, IP10, CX3CL1, and reactive oxygen species, which are components of the senescence-associated secretory phenotype. Thus, re-engagement of cell cycle-associated proteins and a senescence-associated secretory phenotype could be fundamental components of neuronal dysfunction in ALS and frontotemporal dementia.
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Affiliation(s)
- Veronica Porterfield
- Department of Neurology, University of Virginia, Charlottesville, VA, USA; University of Virginia Stem Cell Core, Office of Research Core Administration, University of Virginia, Charlottesville, VA, USA; Department of Cell Biology, University of Virginia, Charlottesville, VA, USA
| | - Shahzad S Khan
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Erin P Foff
- Department of Neurology, University of Virginia, Charlottesville, VA, USA
| | - Mehmet Murat Koseoglu
- Department of Biology, University of Virginia, Charlottesville, VA, USA; Department of Pharmacology, University of Virginia, Charlottesville, VA, USA; Fiske Drug Discovery Laboratory, University of Virginia, Charlottesville, VA, USA
| | - Isabella K Blanco
- Department of Pharmacology, University of Virginia, Charlottesville, VA, USA
| | - Sruthi Jayaraman
- Department of Pharmacology, University of Virginia, Charlottesville, VA, USA
| | - Eric Lien
- Department of Pharmacology, University of Virginia, Charlottesville, VA, USA
| | - Michael J McConnell
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA, USA; Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - George S Bloom
- Department of Cell Biology, University of Virginia, Charlottesville, VA, USA; Department of Biology, University of Virginia, Charlottesville, VA, USA; Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - John S Lazo
- Department of Pharmacology, University of Virginia, Charlottesville, VA, USA; Fiske Drug Discovery Laboratory, University of Virginia, Charlottesville, VA, USA
| | - Elizabeth R Sharlow
- Department of Pharmacology, University of Virginia, Charlottesville, VA, USA; Fiske Drug Discovery Laboratory, University of Virginia, Charlottesville, VA, USA.
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15
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Swinnen B, Robberecht W, Van Den Bosch L. RNA toxicity in non-coding repeat expansion disorders. EMBO J 2020; 39:e101112. [PMID: 31721251 PMCID: PMC6939197 DOI: 10.15252/embj.2018101112] [Citation(s) in RCA: 113] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 09/30/2019] [Accepted: 10/09/2019] [Indexed: 12/11/2022] Open
Abstract
Several neurodegenerative disorders like amyotrophic lateral sclerosis (ALS) and spinocerebellar ataxia (SCA) are caused by non-coding nucleotide repeat expansions. Different pathogenic mechanisms may underlie these non-coding repeat expansion disorders. While gain-of-function mechanisms, such as toxicity associated with expression of repeat RNA or toxicity associated with repeat-associated non-ATG (RAN) products, are most frequently connected with these disorders, loss-of-function mechanisms have also been implicated. We review the different pathways that have been linked to non-coding repeat expansion disorders such as C9ORF72-linked ALS/frontotemporal dementia (FTD), myotonic dystrophy, fragile X tremor/ataxia syndrome (FXTAS), SCA, and Huntington's disease-like 2. We discuss modes of RNA toxicity focusing on the identity and the interacting partners of the toxic RNA species. Using the C9ORF72 ALS/FTD paradigm, we further explore the efforts and different methods used to disentangle RNA vs. RAN toxicity. Overall, we conclude that there is ample evidence for a role of RNA toxicity in non-coding repeat expansion diseases.
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Affiliation(s)
- Bart Swinnen
- Department of NeurosciencesExperimental NeurologyLeuven Brain Institute (LBI)KU Leuven – University of LeuvenLeuvenBelgium
- Laboratory of NeurobiologyVIB, Center for Brain & Disease ResearchLeuvenBelgium
- Department of NeurologyUniversity Hospitals LeuvenLeuvenBelgium
| | - Wim Robberecht
- Department of NeurosciencesExperimental NeurologyLeuven Brain Institute (LBI)KU Leuven – University of LeuvenLeuvenBelgium
- Laboratory of NeurobiologyVIB, Center for Brain & Disease ResearchLeuvenBelgium
- Department of NeurologyUniversity Hospitals LeuvenLeuvenBelgium
| | - Ludo Van Den Bosch
- Department of NeurosciencesExperimental NeurologyLeuven Brain Institute (LBI)KU Leuven – University of LeuvenLeuvenBelgium
- Laboratory of NeurobiologyVIB, Center for Brain & Disease ResearchLeuvenBelgium
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16
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St Martin JL, Wang L, Kaprielian Z. Toxicity in ALS: TDP-43 modifiers and C9orf72. Neurosci Lett 2019; 716:134621. [PMID: 31726180 DOI: 10.1016/j.neulet.2019.134621] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 10/24/2019] [Accepted: 11/07/2019] [Indexed: 12/13/2022]
Abstract
Amyotrophic Lateral Sclerosis (ALS) is a devastating and fatal neurodegenerative disease affecting approximately 30,000 individuals in the United States. The average age of onset is 55 years and progression of the disease is rapid with most patients dying of respiratory failure within 3-5 years. Currently available therapeutics have modest effects on patient survival, underscoring the immediate need for more effective medicines. Recent technological advances in next generation sequencing have led to a substantial uptick in the discovery of genes linked to ALS. Since 90 % of ALS cases are sporadic, risk genes identified in familial cases provide invaluable insights into the molecular pathogenesis of the disease. Most notably, TDP-43-expressing neuronal inclusions and C9orf72 mutations have emerged as the key pathological and genetic hallmarks, respectively, of ALS. In this review, we will discuss recent advances in modifiers of TDP-43 toxicity, with an emphasis on Ataxin-2, one of the most well-characterized TDP-43 modifiers. An understanding of Ataxin-2 function and related biological pathways could provide a framework for the discovery of other novel modifiers of TDP-43. We will also describe the pathogenic mechanisms underlying C9orf72 toxicity and how these impact the disease process. Finally, we will explore emerging therapeutic strategies for dampening TDP-43 and C9orf72 toxicity and, ultimately, slowing or halting the progression of ALS.
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Affiliation(s)
| | - Lina Wang
- Amgen, Neuroscience Discovery, Cambridge, MA, United States
| | - Zaven Kaprielian
- Dementia Discovery Foundation US Discovery, Boston, United States.
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17
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Cammack AJ, Atassi N, Hyman T, van den Berg LH, Harms M, Baloh RH, Brown RH, van Es MA, Veldink JH, de Vries BS, Rothstein JD, Drain C, Jockel-Balsarotti J, Malcolm A, Boodram S, Salter A, Wightman N, Yu H, Sherman AV, Esparza TJ, McKenna-Yasek D, Owegi MA, Douthwright C, McCampbell A, Ferguson T, Cruchaga C, Cudkowicz M, Miller TM. Prospective natural history study of C9orf72 ALS clinical characteristics and biomarkers. Neurology 2019; 93:e1605-e1617. [PMID: 31578300 DOI: 10.1212/wnl.0000000000008359] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Accepted: 05/20/2019] [Indexed: 12/13/2022] Open
Abstract
OBJECTIVE To define the natural history of the C9orf72 amyotrophic lateral sclerosis (C9ALS) patient population, develop disease biomarkers, and characterize patient pathologies. METHODS We prospectively collected clinical and demographic data from 116 symptomatic C9ALS and 12 non-amyotrophic lateral sclerosis (ALS) full expansion carriers across 7 institutions in the United States and the Netherlands. In addition, we collected blood samples for DNA repeat size assessment, CSF samples for biomarker identification, and autopsy samples for dipeptide repeat protein (DPR) size determination. Finally, we collected retrospective clinical data via chart review from 208 individuals with C9ALS and 450 individuals with singleton ALS. RESULTS The mean age at onset in the symptomatic prospective cohort was 57.9 ± 8.3 years, and median duration of survival after onset was 36.9 months. The monthly change was -1.8 ± 1.7 for ALS Functional Rating Scale-Revised and -1.4% ± 3.24% of predicted for slow vital capacity. In blood DNA, we found that G4C2 repeat size correlates positively with age. In CSF, we observed that concentrations of poly(GP) negatively correlate with DNA expansion size but do not correlate with measures of disease progression. Finally, we found that size of poly(GP) dipeptides in the brain can reach large sizes similar to that of their DNA repeat derivatives. CONCLUSIONS We present a thorough investigation of C9ALS natural history, providing the basis for C9ALS clinical trial design. We found that clinical features of this genetic subset are less variant than in singleton ALS. In addition, we identified important correlations of C9ALS patient pathologies with clinical and demographic data.
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Affiliation(s)
- Alexander J Cammack
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Nazem Atassi
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Theodore Hyman
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Leonard H van den Berg
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Matthew Harms
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Robert H Baloh
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Robert H Brown
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Michael A van Es
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Jan H Veldink
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Balint S de Vries
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Jeffrey D Rothstein
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Caroline Drain
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Jennifer Jockel-Balsarotti
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Amber Malcolm
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Sonia Boodram
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Amber Salter
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Nicholas Wightman
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Hong Yu
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Alexander V Sherman
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Thomas J Esparza
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Diane McKenna-Yasek
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Margaret A Owegi
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Catherine Douthwright
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | | | - Alexander McCampbell
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Toby Ferguson
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Carlos Cruchaga
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Merit Cudkowicz
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA
| | - Timothy M Miller
- From the Department of Neurology (A.J.C., T.H., C.D., J.J.-B., A.M., S.B., A.S., T.J.E., C.C., T.M.M.), Washington University School of Medicine, St. Louis, MO; Department of Neurology (N.A., H.Y., A.V.S., M.C.), Neurological Clinical Research Institute, Massachusetts General Hospital, Boston; Department of Neurology (L.H.v.d.B., M.A.v.E., J.H.V., B.S.d.V.), Brain Center Rudolf Magnus, University Medical Center Utrecht, University Utrecht, the Netherlands; Department of Neurology (M.H.), Columbia University, New York, NY; Department of Neurology (R.H. Baloh), Cedars-Sinai Medical Center, Los Angeles, CA; Department of Neurology (R.H. Brown, N.W., D.M.-Y., M.A.O., C.D.), University of Massachusetts, Worcester; Department of Neurology (J.D.R.), Johns Hopkins University, Baltimore, MD; and Biogen Inc. (A.M., T.F.), Boston, MA.
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Jiang J, Ravits J. Pathogenic Mechanisms and Therapy Development for C9orf72 Amyotrophic Lateral Sclerosis/Frontotemporal Dementia. Neurotherapeutics 2019; 16:1115-1132. [PMID: 31667754 PMCID: PMC6985338 DOI: 10.1007/s13311-019-00797-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
In 2011, a hexanucleotide repeat expansion in the first intron of the C9orf72 gene was identified as the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). The proposed disease mechanisms include loss of C9orf72 function and gain of toxicity from the bidirectionally transcribed repeat-containing RNAs. Over the last few years, substantial progress has been made to determine the contribution of loss and gain of function in disease pathogenesis. The extensive body of molecular, cellular, animal, and human neuropathological studies is conflicted, but the predominance of evidence favors gain of toxicity as the main pathogenic mechanism for C9orf72 repeat expansions. Alterations in several downstream cellular functions, such as nucleocytoplasmic transport and autophagy, are implicated. Exciting progress has also been made in therapy development targeting this mutation, such as by antisense oligonucleotide therapies targeting sense transcripts and small molecules targeting nucleocytoplasmic transport, and these are now in phase 1 clinical trials.
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Affiliation(s)
- Jie Jiang
- Department of Cell Biology, Emory University, Atlanta, GA, 30322, USA.
| | - John Ravits
- Department of Neurosciences, University of California at San Diego, La Jolla, CA, 92093, USA.
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Abstract
The discovery that repeat expansions in the C9orf72 gene are a frequent cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) has revolutionized our understanding of these diseases. Substantial headway has been made in characterizing C9orf72-mediated disease and unravelling its underlying aetiopathogenesis. Three main disease mechanisms have been proposed: loss of function of the C9orf72 protein and toxic gain of function from C9orf72 repeat RNA or from dipeptide repeat proteins produced by repeat-associated non-ATG translation. Several downstream processes across a range of cellular functions have also been implicated. In this article, we review the pathological and mechanistic features of C9orf72-associated FTD and ALS (collectively termed C9FTD/ALS), the model systems used to study these conditions, and the probable initiators of downstream disease mechanisms. We suggest that a combination of upstream mechanisms involving both loss and gain of function and downstream cellular pathways involving both cell-autonomous and non-cell-autonomous effects contributes to disease progression.
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Affiliation(s)
- Rubika Balendra
- Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK.,Department of Genetics, Evolution and Environment, Institute of Healthy Ageing, UCL, London, UK
| | - Adrian M Isaacs
- Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK. .,UK Dementia Research Institute at UCL, UCL Institute of Neurology, London, UK.
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Ragagnin AMG, Shadfar S, Vidal M, Jamali MS, Atkin JD. Motor Neuron Susceptibility in ALS/FTD. Front Neurosci 2019; 13:532. [PMID: 31316328 PMCID: PMC6610326 DOI: 10.3389/fnins.2019.00532] [Citation(s) in RCA: 119] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 05/08/2019] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by the death of both upper and lower motor neurons (MNs) in the brain, brainstem and spinal cord. The neurodegenerative mechanisms leading to MN loss in ALS are not fully understood. Importantly, the reasons why MNs are specifically targeted in this disorder are unclear, when the proteins associated genetically or pathologically with ALS are expressed ubiquitously. Furthermore, MNs themselves are not affected equally; specific MNs subpopulations are more susceptible than others in both animal models and human patients. Corticospinal MNs and lower somatic MNs, which innervate voluntary muscles, degenerate more readily than specific subgroups of lower MNs, which remain resistant to degeneration, reflecting the clinical manifestations of ALS. In this review, we discuss the possible factors intrinsic to MNs that render them uniquely susceptible to neurodegeneration in ALS. We also speculate why some MN subpopulations are more vulnerable than others, focusing on both their molecular and physiological properties. Finally, we review the anatomical network and neuronal microenvironment as determinants of MN subtype vulnerability and hence the progression of ALS.
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Affiliation(s)
- Audrey M G Ragagnin
- Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
| | - Sina Shadfar
- Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
| | - Marta Vidal
- Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
| | - Md Shafi Jamali
- Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
| | - Julie D Atkin
- Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia.,Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, Australia
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McCauley ME, Baloh RH. Inflammation in ALS/FTD pathogenesis. Acta Neuropathol 2019; 137:715-730. [PMID: 30465257 PMCID: PMC6482122 DOI: 10.1007/s00401-018-1933-9] [Citation(s) in RCA: 179] [Impact Index Per Article: 35.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 11/08/2018] [Accepted: 11/09/2018] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are neurodegenerative diseases that overlap in their clinical presentation, pathology and genetics, and likely represent a spectrum of one underlying disease. In ALS/FTD patients, neuroinflammation characterized by innate immune responses of tissue-resident glial cells is uniformly present on end-stage pathology, and human imaging studies and rodent models support that neuroinflammation begins early in disease pathogenesis. Additionally, changes in circulating immune cell populations and cytokines are found in ALS/FTD patients, and there is evidence for an autoinflammatory state. However, despite the prominent role of neuro- and systemic inflammation in ALS/FTD, and experimental evidence in rodents that altering microglial function can mitigate pathology, therapeutic approaches to decrease inflammation have thus far failed to alter disease course in humans. Here, we review the characteristics of inflammation in ALS/FTD in both the nervous and peripheral immune systems. We further discuss evidence for direct influence on immune cell function by mutations in ALS/FTD genes including C9orf72, TBK1 and OPTN, and how this could lead to the altered innate immune system “tone” observed in these patients.
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22
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Martier R, Liefhebber JM, Miniarikova J, van der Zon T, Snapper J, Kolder I, Petry H, van Deventer SJ, Evers MM, Konstantinova P. Artificial MicroRNAs Targeting C9orf72 Can Reduce Accumulation of Intra-nuclear Transcripts in ALS and FTD Patients. MOLECULAR THERAPY. NUCLEIC ACIDS 2019; 14:593-608. [PMID: 30776581 PMCID: PMC6378669 DOI: 10.1016/j.omtn.2019.01.010] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 01/22/2019] [Accepted: 01/22/2019] [Indexed: 12/13/2022]
Abstract
The most common pathogenic mutation in amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) is an intronic GGGGCC (G4C2) repeat in the chromosome 9 open reading frame 72 (C9orf72) gene. Cellular toxicity due to RNA foci and dipeptide repeat (DPR) proteins produced by the sense and antisense repeat-containing transcripts is thought to underlie the pathogenesis of both diseases. RNA sequencing (RNA-seq) data of C9orf72-ALS patients and controls were analyzed to better understand the sequence conservation of C9orf72 in patients. MicroRNAs were developed in conserved regions to silence C9orf72 (miC), and the feasibility of different silencing approaches was demonstrated in reporter overexpression systems. In addition, we demonstrated the feasibility of a bidirectional targeting approach by expressing two concatenated miC hairpins. The efficacy of miC was confirmed by the reduction of endogenously expressed C9orf72 mRNA, in both nucleus and cytoplasm, and an ∼50% reduction of nuclear RNA foci in (G4C2)44-expressing cells. Ultimately, two miC candidates were incorporated in adeno-associated virus vector serotype 5 (AAV5), and silencing of C9orf72 was demonstrated in HEK293T cells and induced pluripotent stem cell (iPSC)-derived neurons. These data support the feasibility of microRNA (miRNA)-based and AAV-delivered gene therapy that could alleviate the gain of toxicity seen in ALS and FTD patients.
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Affiliation(s)
- Raygene Martier
- Department of Research & Development, uniQure Biopharma B.V., Amsterdam, the Netherlands; Department of Gastroenterology and Hepatology, Leiden University Medical Center, Leiden, the Netherlands
| | - Jolanda M Liefhebber
- Department of Research & Development, uniQure Biopharma B.V., Amsterdam, the Netherlands
| | - Jana Miniarikova
- Department of Research & Development, uniQure Biopharma B.V., Amsterdam, the Netherlands
| | - Tom van der Zon
- Department of Research & Development, uniQure Biopharma B.V., Amsterdam, the Netherlands
| | - Jolanda Snapper
- Department of Research & Development, uniQure Biopharma B.V., Amsterdam, the Netherlands
| | - Iris Kolder
- BaseClear B.V., Sylviusweg 74, 2333 BE, Leiden, the Netherlands
| | - Harald Petry
- Department of Research & Development, uniQure Biopharma B.V., Amsterdam, the Netherlands
| | - Sander J van Deventer
- Department of Research & Development, uniQure Biopharma B.V., Amsterdam, the Netherlands; Department of Gastroenterology and Hepatology, Leiden University Medical Center, Leiden, the Netherlands
| | - Melvin M Evers
- Department of Research & Development, uniQure Biopharma B.V., Amsterdam, the Netherlands
| | - Pavlina Konstantinova
- Department of Research & Development, uniQure Biopharma B.V., Amsterdam, the Netherlands.
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Alrafiah AR. From Mouse Models to Human Disease: An Approach for Amyotrophic Lateral Sclerosis. In Vivo 2018; 32:983-998. [PMID: 30150420 DOI: 10.21873/invivo.11339] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Revised: 05/22/2018] [Accepted: 05/31/2018] [Indexed: 02/06/2023]
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal adult-onset neurodegenerative disorder. There are several genetic mutations that lead to ALS development, such as chromosome 9 hexanucleotide repeat 72 (C9ORF72), transactive response DNA-binding protein (TARDBP), superoxide dismutase 1 (SOD1) and fused in sarcoma (FUS). ALS is associated with disrupted gene homeostasis causing aberrant RNA processing or toxic pathology. Several animal models of ALS disease have been developed to understand whether TARDBP-mediated neurodegeneration results from a gain or a loss of function of the protein, however, none exactly mimic the pathophysiology and the phenotype of human ALS. Here, the pathophysiology of specific ALS-linked gene mutations is discussed. Furthermore, some of the generated mouse models, as well as the similarities and differences between these models, are comprehensively reviewed. Further refinement of mouse models will likely aid the development of a better form of model that mimics human ALS. However, disrupted gene homeostasis that causes mutation can result in an ALS-like syndrome, increasing concerns about whether neurodegeneration and other effects in these models are due to the mutation or to gene overexpression. Research on the pleiotropic role of different proteins present in motor neurons is also summarized. The development of better mouse models that closely mimic human ALS will help identify potential therapeutic targets for this disease.
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Affiliation(s)
- Aziza Rashed Alrafiah
- Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences and Neuroscience Research Unit, King Abdulaziz University, Jeddah, Saudi Arabia
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24
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Ueyama M, Nagai Y. Repeat Expansion Disease Models. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1076:63-78. [PMID: 29951815 DOI: 10.1007/978-981-13-0529-0_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
Repeat expansion disorders are a group of inherited neuromuscular diseases, which are caused by expansion mutations of repeat sequences in the disease-causing genes. Repeat expansion disorders include a class of diseases caused by repeat expansions in the coding region of the genes, producing mutant proteins with amino acid repeats, mostly the polyglutamine (polyQ) diseases, and another class of diseases caused by repeat expansions in the noncoding regions, producing aberrant RNA with expanded repeats, which are called noncoding repeat expansion diseases. A variety of Drosophila disease models have been established for both types of diseases, and they have made significant contributions toward elucidating the molecular mechanisms of and developing therapies for these neuromuscular diseases.
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Affiliation(s)
- Morio Ueyama
- Department of Neurotherapeutics, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Yoshitaka Nagai
- Department of Neurotherapeutics, Osaka University Graduate School of Medicine, Osaka, Japan.
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25
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Selvaraj BT, Livesey MR, Chandran S. Modeling the C9ORF72 repeat expansion mutation using human induced pluripotent stem cells. Brain Pathol 2018; 27:518-524. [PMID: 28585384 PMCID: PMC8029270 DOI: 10.1111/bpa.12520] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 04/23/2017] [Indexed: 12/12/2022] Open
Abstract
C9ORF72 repeat expansion is the most frequent causal genetic mutation giving rise to amyotrophic lateral sclerosis (ALS) and fronto‐temporal dementia (FTD). The relatively recent discovery of the C9ORF72 repeat expansion in 2011 and the complexity of the mutation have meant that animal models that successfully recapitulate human C9ORF72 repeat expansion‐mediated disease are only now emerging. Concurrent advances in the use of patient‐derived induced pluripotent stem cells (iPSCs) to model aspects of neurological disease offers an additional approach for the study of C9ORF72 mutation. This review focuses on the opportunities of human C9ORF72 iPSC platforms to model pathological aspects of disease and how findings compare with other existing models of disease and post mortem data.
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Affiliation(s)
- Bhuvaneish T Selvaraj
- MRC Centre for Regenerative Medicine, University of Edinburgh, Edinburgh, EH16 4UU, UK.,Euan MacDonald Centre for MND Research, University of Edinburgh, Edinburgh, EH16 4SB, UK.,Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, EH16 4SB, UK
| | - Matthew R Livesey
- Euan MacDonald Centre for MND Research, University of Edinburgh, Edinburgh, EH16 4SB, UK.,Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, EH16 4SB, UK.,Centre for Integrative Physiology, University of Edinburgh, EH8 9XD, UK
| | - Siddharthan Chandran
- MRC Centre for Regenerative Medicine, University of Edinburgh, Edinburgh, EH16 4UU, UK.,Euan MacDonald Centre for MND Research, University of Edinburgh, Edinburgh, EH16 4SB, UK.,Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, EH16 4SB, UK.,Centre for Brain Development and Repair, inStem, Bangalore, 560065, Karnataka, India
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26
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Cruchaga C, Del-Aguila JL, Saef B, Black K, Fernandez MV, Budde J, Ibanez L, Deming Y, Kapoor M, Tosto G, Mayeux RP, Holtzman DM, Fagan AM, Morris JC, Bateman RJ, Goate AM, Harari O. Polygenic risk score of sporadic late-onset Alzheimer's disease reveals a shared architecture with the familial and early-onset forms. Alzheimers Dement 2018; 14:205-214. [PMID: 28943286 PMCID: PMC5803427 DOI: 10.1016/j.jalz.2017.08.013] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 07/31/2017] [Accepted: 08/18/2017] [Indexed: 01/01/2023]
Abstract
OBJECTIVE To determine whether the extent of overlap of the genetic architecture among the sporadic late-onset Alzheimer's Disease (sLOAD), familial late-onset AD (fLOAD), sporadic early-onset AD (sEOAD), and autosomal dominant early-onset AD (eADAD). METHODS Polygenic risk scores (PRSs) were constructed using previously identified 21 genome-wide significant loci for LOAD risk. RESULTS We found that there is an overlap in the genetic architecture among sEOAD, fLOAD, and sLOAD. The highest association of the PRS and risk (odds ratio [OR] = 2.27; P = 1.29 × 10-7) was observed in sEOAD, followed by fLOAD (OR = 1.75; P = 1.12 × 10-7) and sLOAD (OR = 1.40; P = 1.21 × 10-3). The PRS was associated with cerebrospinal fluid ptau181-Aβ42 on eADAD (P = 4.36 × 10-2). CONCLUSION Our analysis confirms that the genetic factors identified for LOAD modulate risk in sLOAD and fLOAD and also sEOAD cohorts. Specifically, our results suggest that the burden of these risk variants is associated with familial clustering and earlier onset of AD. Although these variants are not associated with risk in the eADAD, they may be modulating age at onset.
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Affiliation(s)
- Carlos Cruchaga
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA; Knight Alzheimer's Disease Research Center, Washington University School of Medicine, St. Louis, MO, USA; Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, MO, USA
| | - Jorge L Del-Aguila
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA
| | - Benjamin Saef
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA
| | - Kathleen Black
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA
| | | | - John Budde
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA
| | - Laura Ibanez
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA
| | - Yuetiva Deming
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA
| | - Manav Kapoor
- Ronald M. Loeb Center for Alzheimer's Disease, Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Giuseppe Tosto
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University College of Physicians and Surgeons, New York, NY, USA; Gertrude H. Sergievsky Center, Columbia University College of Physicians and Surgeons, New York, NY, USA; Department of Neurology, Columbia University College of Physicians and Surgeons, New York-Presbyterian Hospital, New York, NY, USA
| | - Richard P Mayeux
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University College of Physicians and Surgeons, New York, NY, USA; Gertrude H. Sergievsky Center, Columbia University College of Physicians and Surgeons, New York, NY, USA; School of Medicine, Mother and Teacher Pontifical Catholic University, Santiago, Dominican Republic
| | - David M Holtzman
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA; Knight Alzheimer's Disease Research Center, Washington University School of Medicine, St. Louis, MO, USA; Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA
| | - Anne M Fagan
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA; Knight Alzheimer's Disease Research Center, Washington University School of Medicine, St. Louis, MO, USA; Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA
| | - John C Morris
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA; Knight Alzheimer's Disease Research Center, Washington University School of Medicine, St. Louis, MO, USA; Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA
| | - Randall J Bateman
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA; Knight Alzheimer's Disease Research Center, Washington University School of Medicine, St. Louis, MO, USA; Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA
| | - Alison M Goate
- Ronald M. Loeb Center for Alzheimer's Disease, Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Oscar Harari
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA.
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27
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Fernández MV, Kim JH, Budde JP, Black K, Medvedeva A, Saef B, Deming Y, Del-Aguila J, Ibañez L, Dube U, Harari O, Norton J, Chasse R, Morris JC, Goate A, Cruchaga C. Analysis of neurodegenerative Mendelian genes in clinically diagnosed Alzheimer Disease. PLoS Genet 2017; 13:e1007045. [PMID: 29091718 PMCID: PMC5683650 DOI: 10.1371/journal.pgen.1007045] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 11/13/2017] [Accepted: 09/27/2017] [Indexed: 12/12/2022] Open
Abstract
Alzheimer disease (AD), Frontotemporal lobar degeneration (FTD), Amyotrophic lateral sclerosis (ALS) and Parkinson disease (PD) have a certain degree of clinical, pathological and molecular overlap. Previous studies indicate that causative mutations in AD and FTD/ALS genes can be found in clinical familial AD. We examined the presence of causative and low frequency coding variants in the AD, FTD, ALS and PD Mendelian genes, in over 450 families with clinical history of AD and over 11,710 sporadic cases and cognitive normal participants from North America. Known pathogenic mutations were found in 1.05% of the sporadic cases, in 0.69% of the cognitively normal participants and in 4.22% of the families. A trend towards enrichment, albeit non-significant, was observed for most AD, FTD and PD genes. Only PSEN1 and PINK1 showed consistent association with AD cases when we used ExAC as the control population. These results suggest that current study designs may contain heterogeneity and contamination of the control population, and that current statistical methods for the discovery of novel genes with real pathogenic variants in complex late onset diseases may be inadequate or underpowered to identify genes carrying pathogenic mutations.
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Affiliation(s)
- Maria Victoria Fernández
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, United States of America
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, MO, United States of America
| | - Jong Hun Kim
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, United States of America
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, MO, United States of America
- Department of Neurology, Dementia Center, Ilsan hospital, National Health Insurance Service, Goyang, South Korea
| | - John P. Budde
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, United States of America
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, MO, United States of America
| | - Kathleen Black
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, United States of America
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, MO, United States of America
| | - Alexandra Medvedeva
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, United States of America
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, MO, United States of America
| | - Ben Saef
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, United States of America
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, MO, United States of America
| | - Yuetiva Deming
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, United States of America
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, MO, United States of America
| | - Jorge Del-Aguila
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, United States of America
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, MO, United States of America
| | - Laura Ibañez
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, United States of America
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, MO, United States of America
| | - Umber Dube
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, United States of America
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, MO, United States of America
- Medical Scientist Training Program, Division of Biology and Biomedical sciences, School of Medicine, Washington University in Saint Louis, St. Louis, MO, United States of America
| | - Oscar Harari
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, United States of America
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, MO, United States of America
| | - Joanne Norton
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, United States of America
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, MO, United States of America
| | - Rachel Chasse
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, United States of America
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, MO, United States of America
| | - John C. Morris
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, MO, United States of America
- Knight Alzheimer's Disease Research Center, Washington University School of Medicine, St. Louis, MO, United States of America
| | - Alison Goate
- Ronald M. Loeb Center for Alzheimer’s disease, Dept of Neuroscience, Icahn School of Medicine at Mount Sinai, ICAHN 10–52, New York, NY, United States of America
| | | | | | - Carlos Cruchaga
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, United States of America
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, MO, United States of America
- * E-mail:
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28
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Moens TG, Partridge L, Isaacs AM. Genetic models of C9orf72: what is toxic? Curr Opin Genet Dev 2017; 44:92-101. [PMID: 28364657 DOI: 10.1016/j.gde.2017.01.006] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 01/13/2017] [Accepted: 01/18/2017] [Indexed: 12/11/2022]
Abstract
A hexanucleotide repeat expansion in the gene C9orf72 is the most common genetic cause of both amyotrophic lateral sclerosis and frontotemporal dementia. Pathogenesis may occur either due to loss of function of the C9orf72 gene, or a toxic gain of function, via the production of repetitive sense and antisense RNA and/or repetitive dipeptide repeat proteins. Recently, mouse knockouts have suggested that a loss of function of C9orf72 alone is insufficient to lead to neurodegeneration, whilst overexpression of hexanucleotide DNA is sufficient in a wide range of model systems. Additionally, models have now been created to attempt to study the effects of repetitive RNA and dipeptide proteins in isolation and thus determine their relevance to disease.
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Affiliation(s)
- Thomas G Moens
- Department of Neurodegenerative Disease, UCL Institute of Neurology, London WC1N 3BG, UK; Department of Genetics, Evolution and Environment, Institute of Healthy Ageing, University College London, London WC1E 6BT, UK
| | - Linda Partridge
- Department of Genetics, Evolution and Environment, Institute of Healthy Ageing, University College London, London WC1E 6BT, UK; Max Planck Institute for Biology of Ageing, Robert-Koch-Str. 21, 50931 Cologne, Germany
| | - Adrian M Isaacs
- Department of Neurodegenerative Disease, UCL Institute of Neurology, London WC1N 3BG, UK.
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29
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Koon AC, Chan HYE. Drosophila melanogaster As a Model Organism to Study RNA Toxicity of Repeat Expansion-Associated Neurodegenerative and Neuromuscular Diseases. Front Cell Neurosci 2017; 11:70. [PMID: 28377694 PMCID: PMC5359753 DOI: 10.3389/fncel.2017.00070] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 02/27/2017] [Indexed: 12/14/2022] Open
Abstract
For nearly a century, the fruit fly, Drosophila melanogaster, has proven to be a valuable tool in our understanding of fundamental biological processes, and has empowered our discoveries, particularly in the field of neuroscience. In recent years, Drosophila has emerged as a model organism for human neurodegenerative and neuromuscular disorders. In this review, we highlight a number of recent studies that utilized the Drosophila model to study repeat-expansion associated diseases (READs), such as polyglutamine diseases, fragile X-associated tremor/ataxia syndrome (FXTAS), myotonic dystrophy type 1 (DM1) and type 2 (DM2), and C9ORF72-associated amyotrophic lateral sclerosis/frontotemporal dementia (C9-ALS/FTD). Discoveries regarding the possible mechanisms of RNA toxicity will be focused here. These studies demonstrate Drosophila as an excellent in vivo model system that can reveal novel mechanistic insights into human disorders, providing the foundation for translational research and therapeutic development.
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Affiliation(s)
- Alex C Koon
- Laboratory of Drosophila ResearchHong Kong, Hong Kong; Biochemistry ProgramHong Kong, Hong Kong
| | - Ho Yin Edwin Chan
- Laboratory of Drosophila ResearchHong Kong, Hong Kong; Biochemistry ProgramHong Kong, Hong Kong; Cell and Molecular Biology ProgramHong Kong, Hong Kong; Molecular Biotechnology Program, Faculty of Science, School of Life SciencesHong Kong, Hong Kong; School of Life Sciences, Gerald Choa Neuroscience Centre, The Chinese University of Hong KongHong Kong, Hong Kong
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30
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Van Mossevelde S, van der Zee J, Cruts M, Van Broeckhoven C. Relationship between C9orf72 repeat size and clinical phenotype. Curr Opin Genet Dev 2017; 44:117-124. [PMID: 28319737 DOI: 10.1016/j.gde.2017.02.008] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 01/19/2017] [Accepted: 02/10/2017] [Indexed: 12/12/2022]
Abstract
Patient carriers of a C9orf72 repeat expansion exhibit remarkable heterogeneous clinical and pathological characteristics suggesting the presence of modifying factors. In accordance with other repeat expansion diseases, repeat length is the prime candidate as a genetic modifier. Observations of earlier onset ages in younger generations of large families suggested a mechanism of disease anticipation. Yet, studies of repeat size and onset age have led to conflicting results. Also, the correlation between repeat size and diagnosis is poorly understood. We review what has been published regarding C9orf72 repeat size as modifier for phenotypic characteristics. Conclusive evidence is lacking, partly due to the difficulties in accurately defining the exact repeat size and the presence of repeat variability due to somatic mosaicism.
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Affiliation(s)
- Sara Van Mossevelde
- Center for Molecular Neurology, VIB, Universiteitsplein 1, 2610 Antwerp, Belgium; Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Universiteitsplein 1, 2610 Antwerp, Belgium; Department of Neurology and Memory Clinic, Hospital Network Antwerp Hoge Beuken, Commandant Weynsstraat 165, 2660 Hoboken, Belgium; Department of Neurology, Antwerp University Hospital, Wilrijkstraat 10, 2650 Edegem, Belgium
| | - Julie van der Zee
- Center for Molecular Neurology, VIB, Universiteitsplein 1, 2610 Antwerp, Belgium; Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Universiteitsplein 1, 2610 Antwerp, Belgium
| | - Marc Cruts
- Center for Molecular Neurology, VIB, Universiteitsplein 1, 2610 Antwerp, Belgium; Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Universiteitsplein 1, 2610 Antwerp, Belgium
| | - Christine Van Broeckhoven
- Center for Molecular Neurology, VIB, Universiteitsplein 1, 2610 Antwerp, Belgium; Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Universiteitsplein 1, 2610 Antwerp, Belgium.
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31
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Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal disorder that is characterized by a progressive degeneration of the upper and lower motor neurons. Most cases appear to be sporadic, but 5-10 % of cases have a family history of the disease. High-throughput DNA sequencing and related genomic capture tools are methodological advances which have rapidly contributed to an acceleration in the discovery of genetic risk factors for both familial and sporadic ALS. It is interesting to note that as the number of ALS genes grows, many of the proteins they encode are in shared intracellular processes. This review will summarize some of the recent advances and gene discovery made in ALS.
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32
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Burrell JR, Halliday GM, Kril JJ, Ittner LM, Götz J, Kiernan MC, Hodges JR. The frontotemporal dementia-motor neuron disease continuum. Lancet 2016; 388:919-31. [PMID: 26987909 DOI: 10.1016/s0140-6736(16)00737-6] [Citation(s) in RCA: 240] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Early reports of cognitive and behavioural deficits in motor neuron disease might have been overlooked initially, but the concept of a frontotemporal dementia-motor neuron disease continuum has emerged during the past decade. Frontotemporal dementia-motor neuron disease is now recognised as an important dementia syndrome, which presents substantial challenges for diagnosis and management. Frontotemporal dementia, motor neuron disease, and frontotemporal dementia-motor neuron disease are characterised by overlapping patterns of TAR DNA binding protein (TDP-43) pathology, while the chromosome 9 open reading frame 72 (C9orf72) repeat expansion is common across the disease spectrum. Indeed, the C9orf72 repeat expansion provides important clues to disease pathogenesis and suggests potential therapeutic targets. Variable diagnostic criteria identify motor, cognitive, and behavioural deficits, but further refinement is needed to define the clinical syndromes encountered in frontotemporal dementia-motor neuron disease.
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Affiliation(s)
- James R Burrell
- Neuroscience Research Australia, Sydney, NSW, Australia; Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia
| | - Glenda M Halliday
- Neuroscience Research Australia, Sydney, NSW, Australia; Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia
| | - Jillian J Kril
- Disciplines of Medicine and Pathology, Sydney Medical School, University of Sydney, Sydney, NSW, Australia
| | - Lars M Ittner
- Neuroscience Research Australia, Sydney, NSW, Australia; Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia
| | - Jürgen Götz
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, University of Queensland, Brisbane, QLD, Australia
| | - Matthew C Kiernan
- Neuroscience Research Australia, Sydney, NSW, Australia; Brain and Mind Centre, Sydney Medical School, University of Sydney, Sydney, NSW, Australia
| | - John R Hodges
- Neuroscience Research Australia, Sydney, NSW, Australia; Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia.
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33
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Jovičić A, Paul JW, Gitler AD. Nuclear transport dysfunction: a common theme in amyotrophic lateral sclerosis and frontotemporal dementia. J Neurochem 2016; 138 Suppl 1:134-44. [PMID: 27087014 DOI: 10.1111/jnc.13642] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Revised: 04/03/2016] [Accepted: 04/08/2016] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are neurodegenerative diseases with overlapping genetic factors and pathology. On the cellular level, a majority of ALS and FTD cases are characterized by nuclear clearance and cytoplasmic aggregation of otherwise nuclear proteins, TAR DNA-binding protein 43 (TDP-43), or fused in sarcoma. Recent studies investigating cellular pathways perturbed by genetic risk factors for ALS/FTD converge on nucleocytoplasmic transport dysfunction as a mechanism leading to disease pathophysiology. We propose that mutations in FUS and hexanucleotide expansions in C9orf72 and aging all converge on the impairment of nucleocytoplasmic transport, which results in the hallmark pathological feature of ALS/FTD - cytoplasmic aggregation of TDP-43 or FUS.
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Affiliation(s)
- Ana Jovičić
- Department of Genetics, Stanford University School of Medicine, Stanford, California, USA
| | - Joseph W Paul
- Department of Genetics, Stanford University School of Medicine, Stanford, California, USA
| | - Aaron D Gitler
- Department of Genetics, Stanford University School of Medicine, Stanford, California, USA
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34
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Todd TW, Petrucelli L. Insights into the pathogenic mechanisms of Chromosome 9 open reading frame 72 (C9orf72) repeat expansions. J Neurochem 2016; 138 Suppl 1:145-62. [PMID: 27016280 DOI: 10.1111/jnc.13623] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Revised: 03/04/2016] [Accepted: 03/21/2016] [Indexed: 12/12/2022]
Abstract
The identification of a hexanucleotide repeat expansion in a non-coding region of C9orf72 as a major cause of both frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) drastically changed the field of research on both of these conditions. Yet, despite the vast amount of work aimed at elucidating the molecular mechanisms underlying the role of this repeat in disease, the exact pathomechanisms are still unclear. A reduction in the expression of the C9orf72 gene is observed in patients, but a gain-of-function model is now preferred. The hexanucleotide repeat expansion forms RNA foci in the central nervous system (CNS) of repeat-positive FTD and ALS patients, and these foci are believed to sequester RNA-binding proteins (RBPs) and impair their function in RNA processing. At the same time, the repeat undergoes repeat-associated non-ATG translation to produce dipeptide repeat proteins that also form inclusions in the patient CNS. Studies from cells and flies suggest that these proteins may also be an important factor in the disease. Finally, the hexanucleotide repeat also induces the mislocalization and aggregation of TAR DNA-binding protein 43 (TDP-43) through an as yet unknown mechanism. This review covers the different potential pathogenic factors that have been put forth for C9orf72-repeat-associated FTD and ALS (C9-FTD/ALS), while highlighting some remaining questions. A repeat expansion in C9orf72 is a common cause of both frontal temporal dementia and amyotrophic lateral sclerosis. Although there is a decrease in C9orf72 expression in patients, this repeat is believed to induce disease primarily through an unknown gain-of-function mechanism involving the RNA, repeat-associated non-AUG translation, or both. This review summarizes and discusses current knowledge on C9orf72 repeat-associated pathophysiology. This article is part of the Frontotemporal Dementia special issue.
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Affiliation(s)
- Tiffany W Todd
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
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35
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The expanding biology of the C9orf72 nucleotide repeat expansion in neurodegenerative disease. Nat Rev Neurosci 2016; 17:383-95. [PMID: 27150398 DOI: 10.1038/nrn.2016.38] [Citation(s) in RCA: 151] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
A nucleotide repeat expansion (NRE) within the chromosome 9 open reading frame 72 (C9orf72) gene was the first of this type of mutation to be linked to multiple neurological conditions, including amyotrophic lateral sclerosis and frontotemporal dementia. The pathogenic mechanisms through which the C9orf72 NRE contributes to these disorders include loss of C9orf72 function and gain-of-function mechanisms of C9orf72 driven by toxic RNA and protein species encoded by the NRE. These mechanisms have been linked to several cellular defects - including nucleocytoplasmic trafficking deficits and nuclear stress - that have been observed in both patients and animal models.
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Jiang J, Zhu Q, Gendron TF, Saberi S, McAlonis-Downes M, Seelman A, Stauffer JE, Jafar-Nejad P, Drenner K, Schulte D, Chun S, Sun S, Ling SC, Myers B, Engelhardt J, Katz M, Baughn M, Platoshyn O, Marsala M, Watt A, Heyser CJ, Ard MC, De Muynck L, Daughrity LM, Swing DA, Tessarollo L, Jung CJ, Delpoux A, Utzschneider DT, Hedrick SM, de Jong PJ, Edbauer D, Van Damme P, Petrucelli L, Shaw CE, Bennett CF, Da Cruz S, Ravits J, Rigo F, Cleveland DW, Lagier-Tourenne C. Gain of Toxicity from ALS/FTD-Linked Repeat Expansions in C9ORF72 Is Alleviated by Antisense Oligonucleotides Targeting GGGGCC-Containing RNAs. Neuron 2016; 90:535-50. [PMID: 27112497 PMCID: PMC4860075 DOI: 10.1016/j.neuron.2016.04.006] [Citation(s) in RCA: 384] [Impact Index Per Article: 48.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 02/29/2016] [Accepted: 04/04/2016] [Indexed: 12/13/2022]
Abstract
Hexanucleotide expansions in C9ORF72 are the most frequent genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia. Disease mechanisms were evaluated in mice expressing C9ORF72 RNAs with up to 450 GGGGCC repeats or with one or both C9orf72 alleles inactivated. Chronic 50% reduction of C9ORF72 did not provoke disease, while its absence produced splenomegaly, enlarged lymph nodes, and mild social interaction deficits, but not motor dysfunction. Hexanucleotide expansions caused age-, repeat-length-, and expression-level-dependent accumulation of RNA foci and dipeptide-repeat proteins synthesized by AUG-independent translation, accompanied by loss of hippocampal neurons, increased anxiety, and impaired cognitive function. Single-dose injection of antisense oligonucleotides (ASOs) that target repeat-containing RNAs but preserve levels of mRNAs encoding C9ORF72 produced sustained reductions in RNA foci and dipeptide-repeat proteins, and ameliorated behavioral deficits. These efforts identify gain of toxicity as a central disease mechanism caused by repeat-expanded C9ORF72 and establish the feasibility of ASO-mediated therapy.
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Affiliation(s)
- Jie Jiang
- Ludwig Institute for Cancer Research, University of California, San Diego, La Jolla, CA 92093, USA; Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Qiang Zhu
- Ludwig Institute for Cancer Research, University of California, San Diego, La Jolla, CA 92093, USA
| | - Tania F Gendron
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL 32224, USA
| | - Shahram Saberi
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Melissa McAlonis-Downes
- Ludwig Institute for Cancer Research, University of California, San Diego, La Jolla, CA 92093, USA
| | - Amanda Seelman
- Ludwig Institute for Cancer Research, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jennifer E Stauffer
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | | | - Kevin Drenner
- Ludwig Institute for Cancer Research, University of California, San Diego, La Jolla, CA 92093, USA
| | - Derek Schulte
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Seung Chun
- Ionis Pharmaceuticals, 2855 Gazelle Court, Carlsbad, CA 92010, USA
| | - Shuying Sun
- Ludwig Institute for Cancer Research, University of California, San Diego, La Jolla, CA 92093, USA
| | - Shuo-Chien Ling
- Ludwig Institute for Cancer Research, University of California, San Diego, La Jolla, CA 92093, USA; Department of Physiology, National University of Singapore, 12 Science Drive 2, Singapore 117549, Singapore
| | - Brian Myers
- Ludwig Institute for Cancer Research, University of California, San Diego, La Jolla, CA 92093, USA
| | | | - Melanie Katz
- Ionis Pharmaceuticals, 2855 Gazelle Court, Carlsbad, CA 92010, USA
| | - Michael Baughn
- Ludwig Institute for Cancer Research, University of California, San Diego, La Jolla, CA 92093, USA; Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Oleksandr Platoshyn
- Department of Anesthesiology, University of California, San Diego, La Jolla, CA 92093, USA; Neuroregeneration Laboratory, Sanford Consortium for Regenerative Medicine, 2880 Torrey Pines Scenic Drive, La Jolla, CA 92037, USA
| | - Martin Marsala
- Department of Anesthesiology, University of California, San Diego, La Jolla, CA 92093, USA; Neuroregeneration Laboratory, Sanford Consortium for Regenerative Medicine, 2880 Torrey Pines Scenic Drive, La Jolla, CA 92037, USA; Institute of Neurobiology, Slovak Academy of Sciences, Soltesovej 9, 04001 Kosice, Slovakia
| | - Andy Watt
- Ionis Pharmaceuticals, 2855 Gazelle Court, Carlsbad, CA 92010, USA
| | - Charles J Heyser
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - M Colin Ard
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Louis De Muynck
- Laboratory of Neurobiology, Vesalius Research Center, Experimental Neurology, Department of Neurosciences, KU Leuven/VIB, 3000 Leuven, Belgium; Department of Neurology, University Hospitals Leuven, 3000 Leuven, Belgium
| | - Lillian M Daughrity
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL 32224, USA
| | - Deborah A Swing
- Mouse Cancer Genetics Program, National Cancer Institute, Frederick, MD 21702, USA
| | - Lino Tessarollo
- Mouse Cancer Genetics Program, National Cancer Institute, Frederick, MD 21702, USA
| | - Chris J Jung
- Children's Hospital Oakland Research Institute, 5700 Martin Luther King Jr Way, Oakland, CA 94609, USA
| | - Arnaud Delpoux
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Molecular Biology Section, Division of Biological Sciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Daniel T Utzschneider
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Molecular Biology Section, Division of Biological Sciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Stephen M Hedrick
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Molecular Biology Section, Division of Biological Sciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Pieter J de Jong
- Children's Hospital Oakland Research Institute, 5700 Martin Luther King Jr Way, Oakland, CA 94609, USA
| | - Dieter Edbauer
- German Center for Neurodegenerative Diseases (DZNE), Ludwig-Maximilians University and Munich Cluster of Systems Neurology (SyNergy), Feodor-Lynen Strasse 17, 81377 Munich, Germany
| | - Philip Van Damme
- Laboratory of Neurobiology, Vesalius Research Center, Experimental Neurology, Department of Neurosciences, KU Leuven/VIB, 3000 Leuven, Belgium; Department of Neurology, University Hospitals Leuven, 3000 Leuven, Belgium
| | - Leonard Petrucelli
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL 32224, USA
| | | | - C Frank Bennett
- Ionis Pharmaceuticals, 2855 Gazelle Court, Carlsbad, CA 92010, USA
| | - Sandrine Da Cruz
- Ludwig Institute for Cancer Research, University of California, San Diego, La Jolla, CA 92093, USA
| | - John Ravits
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Frank Rigo
- Ionis Pharmaceuticals, 2855 Gazelle Court, Carlsbad, CA 92010, USA
| | - Don W Cleveland
- Ludwig Institute for Cancer Research, University of California, San Diego, La Jolla, CA 92093, USA; Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA.
| | - Clotilde Lagier-Tourenne
- Ludwig Institute for Cancer Research, University of California, San Diego, La Jolla, CA 92093, USA; Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA.
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Gitler AD, Tsuiji H. There has been an awakening: Emerging mechanisms of C9orf72 mutations in FTD/ALS. Brain Res 2016; 1647:19-29. [PMID: 27059391 DOI: 10.1016/j.brainres.2016.04.004] [Citation(s) in RCA: 117] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 03/30/2016] [Accepted: 04/03/2016] [Indexed: 12/13/2022]
Abstract
The discovery of C9orf72 mutations as the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) has awakened a surge of interest in deciphering how mutations in this mysterious gene cause disease and what can be done to stop it. C9orf72 harbors a hexanucleotide repeat, GGGGCC, in a non-coding region of the gene and a massive expansion of this repeat causes ALS, FTD, or both (FTD/ALS). Many questions lie ahead. What does this gene normally do? What is the consequence of an enormous GGGGCC repeat expansion on that gene's function? Could that hexanucleotide repeat expansion have additional pathological actions unrelated to C9orf72 function? There has been tremendous progress on all fronts in the quest to define how C9orf72 mutations cause disease. Many new experimental models have been constructed and unleashed in powerful genetic screens. Studies in mouse and human patient samples, including iPS-derived neurons, have provided unprecedented insights into pathogenic mechanisms. Three major hypotheses have emerged and are still being hotly debated in the field. These include (1) loss of function owing to decrease in the abundance of C9orf72 protein and its ability to carryout its still unknown cellular role; (2) RNA toxicity from bidirectionally transcribed sense (GGGGCC) and antisense (GGCCCC) transcripts that accumulate in RNA foci and might sequester critical RNA-binding proteins; (3) proteotoxicity from dipeptide repeat proteins produced by an unconventional form of translation from the expanded nucleotide repeats. Here we review the evidence in favor and against each of these three hypotheses. We also suggest additional experiments and considerations that we propose will help clarify which mechanism(s) are most important for driving disease and therefore most critical for considering during the development of therapeutic interventions. This article is part of a Special Issue entitled SI:RNA Metabolism in Disease.
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Affiliation(s)
- Aaron D Gitler
- Department of Genetics, Stanford University School of Medicine, 300 Pasteur Drive, M322 Alway Building, Stanford, CA 94305, USA.
| | - Hitomi Tsuiji
- Department of Biomedical Science, Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabedori, Mizuhoku, Nagoya, Aichi 467-8603, Japan.
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O'Rourke JG, Bogdanik L, Muhammad AKMG, Gendron TF, Kim KJ, Austin A, Cady J, Liu EY, Zarrow J, Grant S, Ho R, Bell S, Carmona S, Simpkinson M, Lall D, Wu K, Daughrity L, Dickson DW, Harms MB, Petrucelli L, Lee EB, Lutz CM, Baloh RH. C9orf72 BAC Transgenic Mice Display Typical Pathologic Features of ALS/FTD. Neuron 2016; 88:892-901. [PMID: 26637796 DOI: 10.1016/j.neuron.2015.10.027] [Citation(s) in RCA: 220] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Revised: 06/16/2015] [Accepted: 09/09/2015] [Indexed: 12/13/2022]
Abstract
Noncoding expansions of a hexanucleotide repeat (GGGGCC) in the C9orf72 gene are the most common cause of familial amyotrophic lateral sclerosis and frontotemporal dementia. Here we report transgenic mice carrying a bacterial artificial chromosome (BAC) containing the full human C9orf72 gene with either a normal allele (15 repeats) or disease-associated expansion (∼100-1,000 repeats; C9-BACexp). C9-BACexp mice displayed pathologic features seen in C9orf72 expansion patients, including widespread RNA foci and repeat-associated non-ATG (RAN) translated dipeptides, which were suppressed by antisense oligonucleotides targeting human C9orf72. Nucleolin distribution was altered, supporting that either C9orf72 transcripts or RAN dipeptides promote nucleolar dysfunction. Despite early and widespread production of RNA foci and RAN dipeptides in C9-BACexp mice, behavioral abnormalities and neurodegeneration were not observed even at advanced ages, supporting the hypothesis that RNA foci and RAN dipeptides occur presymptomatically and are not sufficient to drive neurodegeneration in mice at levels seen in patients.
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Affiliation(s)
- Jacqueline G O'Rourke
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, CA 90048, USA
| | - Laurent Bogdanik
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA
| | - A K M G Muhammad
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, CA 90048, USA
| | - Tania F Gendron
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL 32224, USA
| | - Kevin J Kim
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, CA 90048, USA
| | - Andrew Austin
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA
| | - Janet Cady
- Department of Neurology, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA
| | - Elaine Y Liu
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jonah Zarrow
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, CA 90048, USA
| | - Sharday Grant
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, CA 90048, USA
| | - Ritchie Ho
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, CA 90048, USA
| | - Shaughn Bell
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, CA 90048, USA
| | - Sharon Carmona
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, CA 90048, USA
| | - Megan Simpkinson
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, CA 90048, USA
| | - Deepti Lall
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, CA 90048, USA
| | - Kathryn Wu
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, CA 90048, USA
| | - Lillian Daughrity
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL 32224, USA
| | - Dennis W Dickson
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL 32224, USA
| | - Matthew B Harms
- Department of Neurology, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA
| | - Leonard Petrucelli
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL 32224, USA
| | - Edward B Lee
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Cathleen M Lutz
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA
| | - Robert H Baloh
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, CA 90048, USA; Department of Neurology, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, CA 90048, USA.
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C9orf72 amyotrophic lateral sclerosis and frontotemporal dementia: gain or loss of function? Curr Opin Neurol 2015; 27:515-23. [PMID: 25188012 PMCID: PMC4165481 DOI: 10.1097/wco.0000000000000130] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Purpose of review The molecular mechanisms that underlie chromosome 9 open reading frame 72 (C9orf72)-associated amyotrophic lateral sclerosis and frontotemporal dementia are rapidly emerging. Two potential disease mechanisms have been postulated – gain or loss of function. We provide an overview of recent advances that support or oppose gain-of-function and loss-of-function mechanisms. Recent findings Since the discovery that a noncoding repeat expansion in C9orf72 was responsible for chromosome 9-linked amyotrophic lateral sclerosis and frontotemporal dementia in 2011, a plethora of studies have investigated clinical, pathological and mechanistic aspects of the disease. Loss of function is supported by reduced levels of C9orf72 in patient brain and functional work, revealing a role of the C9orf72 protein in endocytic and autophagic pathways and motor function. Gain of function is supported by the presence in patient brain of both repeat RNA and protein aggregates. Repeat RNA aggregates termed RNA foci, a hallmark of noncoding repeat expansion diseases, have been shown to sequester proteins involved in RNA splicing, editing, nuclear export and nucleolar function. Repeat-associated non-ATG dependent translation gives rise to toxic dipeptide repeat proteins that form inclusions in patient tissue. Antisense oligonucleotides targeting C9orf72 have shown promise for combating gain-of-function toxicity. Summary Rapid progress is being made towards understanding this common genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia. Overall, the weight of data currently sits in favour of gain of function as the most important disease mechanism, which has important implications for the development of effective and targeted therapies.
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Walsh MJ, Cooper-Knock J, Dodd JE, Stopford MJ, Mihaylov SR, Kirby J, Shaw PJ, Hautbergue GM. Invited review: decoding the pathophysiological mechanisms that underlie RNA dysregulation in neurodegenerative disorders: a review of the current state of the art. Neuropathol Appl Neurobiol 2015; 41:109-34. [PMID: 25319671 PMCID: PMC4329338 DOI: 10.1111/nan.12187] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 10/07/2014] [Indexed: 12/12/2022]
Abstract
Altered RNA metabolism is a key pathophysiological component causing several neurodegenerative diseases. Genetic mutations causing neurodegeneration occur in coding and noncoding regions of seemingly unrelated genes whose products do not always contribute to the gene expression process. Several pathogenic mechanisms may coexist within a single neuronal cell, including RNA/protein toxic gain-of-function and/or protein loss-of-function. Genetic mutations that cause neurodegenerative disorders disrupt healthy gene expression at diverse levels, from chromatin remodelling, transcription, splicing, through to axonal transport and repeat-associated non-ATG (RAN) translation. We address neurodegeneration in repeat expansion disorders [Huntington's disease, spinocerebellar ataxias, C9ORF72-related amyotrophic lateral sclerosis (ALS)] and in diseases caused by deletions or point mutations (spinal muscular atrophy, most subtypes of familial ALS). Some neurodegenerative disorders exhibit broad dysregulation of gene expression with the synthesis of hundreds to thousands of abnormal messenger RNA (mRNA) molecules. However, the number and identity of aberrant mRNAs that are translated into proteins - and how these lead to neurodegeneration - remain unknown. The field of RNA biology research faces the challenge of identifying pathophysiological events of dysregulated gene expression. In conclusion, we discuss current research limitations and future directions to improve our characterization of pathological mechanisms that trigger disease onset and progression.
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Affiliation(s)
- M J Walsh
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of SheffieldSheffield, UK
| | - J Cooper-Knock
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of SheffieldSheffield, UK
| | - J E Dodd
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of SheffieldSheffield, UK
| | - M J Stopford
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of SheffieldSheffield, UK
| | - S R Mihaylov
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of SheffieldSheffield, UK
| | - J Kirby
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of SheffieldSheffield, UK
| | - P J Shaw
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of SheffieldSheffield, UK
| | - G M Hautbergue
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of SheffieldSheffield, UK
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Cady J, Allred P, Bali T, Pestronk A, Goate A, Miller TM, Mitra R, Ravits J, Harms MB, Baloh RH. Amyotrophic lateral sclerosis onset is influenced by the burden of rare variants in known amyotrophic lateral sclerosis genes. Ann Neurol 2015; 77:100-13. [PMID: 25382069 PMCID: PMC4293318 DOI: 10.1002/ana.24306] [Citation(s) in RCA: 154] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 10/16/2014] [Accepted: 11/02/2014] [Indexed: 12/11/2022]
Abstract
OBJECTIVE To define the genetic landscape of amyotrophic lateral sclerosis (ALS) and assess the contribution of possible oligogenic inheritance, we aimed to comprehensively sequence 17 known ALS genes in 391 ALS patients from the United States. METHODS Targeted pooled-sample sequencing was used to identify variants in 17 ALS genes. Fragment size analysis was used to define ATXN2 and C9ORF72 expansion sizes. Genotype-phenotype correlations were made with individual variants and total burden of variants. Rare variant associations for risk of ALS were investigated at both the single variant and gene level. RESULTS A total of 64.3% of familial and 27.8% of sporadic subjects carried potentially pathogenic novel or rare coding variants identified by sequencing or an expanded repeat in C9ORF72 or ATXN2; 3.8% of subjects had variants in >1 ALS gene, and these individuals had disease onset 10 years earlier (p = 0.0046) than subjects with variants in a single gene. The number of potentially pathogenic coding variants did not influence disease duration or site of onset. INTERPRETATION Rare and potentially pathogenic variants in known ALS genes are present in >25% of apparently sporadic and 64% of familial patients, significantly higher than previous reports using less comprehensive sequencing approaches. A significant number of subjects carried variants in >1 gene, which influenced the age of symptom onset and supports oligogenic inheritance as relevant to disease pathogenesis.
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Affiliation(s)
- Janet Cady
- Department of Neurology; Washington University. St. Louis, MO, USA
| | - Peggy Allred
- Department of Neurology; Cedars Sinai Medical Center. Los Angeles, CA, USA
| | - Taha Bali
- Department of Neurology; Washington University. St. Louis, MO, USA
| | - Alan Pestronk
- Department of Neurology; Washington University. St. Louis, MO, USA
| | - Alison Goate
- Department of Neurology; Washington University. St. Louis, MO, USA
- Department of Psychiatry; Washington University. St. Louis, MO, USA
- Hope Center for Neurological Disorders; Washington University. St. Louis, MO, USA
| | - Timothy M. Miller
- Department of Neurology; Washington University. St. Louis, MO, USA
- Hope Center for Neurological Disorders; Washington University. St. Louis, MO, USA
| | - Rob Mitra
- Department of Genetics; Washington University. St. Louis, MO, USA
| | - John Ravits
- Department of Neurosciences; University of California, San Diego. La Jolla, CA, USA
| | - Matthew B. Harms
- Department of Neurology; Washington University. St. Louis, MO, USA
- Hope Center for Neurological Disorders; Washington University. St. Louis, MO, USA
| | - Robert H. Baloh
- Department of Neurology; Cedars Sinai Medical Center. Los Angeles, CA, USA
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Liu EY, Russ J, Wu K, Neal D, Suh E, McNally AG, Irwin DJ, Van Deerlin VM, Lee EB. C9orf72 hypermethylation protects against repeat expansion-associated pathology in ALS/FTD. Acta Neuropathol 2014; 128:525-41. [PMID: 24806409 PMCID: PMC4161616 DOI: 10.1007/s00401-014-1286-y] [Citation(s) in RCA: 132] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Revised: 04/24/2014] [Accepted: 04/25/2014] [Indexed: 12/13/2022]
Abstract
Hexanucleotide repeat expansions of C9orf72 are the most common genetic cause of amyotrophic lateral sclerosis and frontotemporal degeneration. The mutation is associated with reduced C9orf72 expression and the accumulation of potentially toxic RNA and protein aggregates. CpG methylation is known to protect the genome against unstable DNA elements and to stably silence inappropriate gene expression. Using bisulfite cloning and restriction enzyme-based methylation assays on DNA from human brain and peripheral blood, we observed CpG hypermethylation involving the C9orf72 promoter in cis to the repeat expansion mutation in approximately one-third of C9orf72 repeat expansion mutation carriers. Promoter hypermethylation of mutant C9orf72 was associated with transcriptional silencing of C9orf72 in patient-derived lymphoblast cell lines, resulting in reduced accumulation of intronic C9orf72 RNA and reduced numbers of RNA foci. Furthermore, demethylation of mutant C9orf72 with 5-aza-deoxycytidine resulted in increased vulnerability of mutant cells to oxidative and autophagic stress. Promoter hypermethylation of repeat expansion carriers was also associated with reduced accumulation of RNA foci and dipeptide repeat protein aggregates in human brains. These results indicate that C9orf72 promoter hypermethylation prevents downstream molecular aberrations associated with the hexanucleotide repeat expansion, suggesting that epigenetic silencing of the mutant C9orf72 allele may represent a protective counter-regulatory response to hexanucleotide repeat expansion.
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Affiliation(s)
- Elaine Y. Liu
- Translational Neuropathology Research Laboratory, Perelman School of Medicine at the University of Pennsylvania, 605B Stellar Chance Laboratories, 422 Curie Blvd, Philadelphia, PA 19104, USA. Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, USA
| | - Jenny Russ
- Translational Neuropathology Research Laboratory, Perelman School of Medicine at the University of Pennsylvania, 605B Stellar Chance Laboratories, 422 Curie Blvd, Philadelphia, PA 19104, USA. Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, USA
| | - Kathryn Wu
- Translational Neuropathology Research Laboratory, Perelman School of Medicine at the University of Pennsylvania, 605B Stellar Chance Laboratories, 422 Curie Blvd, Philadelphia, PA 19104, USA. Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, USA
| | - Donald Neal
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, USA
| | - Eunran Suh
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, USA
| | - Anna G. McNally
- Translational Neuropathology Research Laboratory, Perelman School of Medicine at the University of Pennsylvania, 605B Stellar Chance Laboratories, 422 Curie Blvd, Philadelphia, PA 19104, USA. Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, USA
| | - David J. Irwin
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, USA. Department of Neurology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, USA
| | - Vivianna M. Van Deerlin
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, USA
| | - Edward B. Lee
- Translational Neuropathology Research Laboratory, Perelman School of Medicine at the University of Pennsylvania, 605B Stellar Chance Laboratories, 422 Curie Blvd, Philadelphia, PA 19104, USA
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Mizielinska S, Grönke S, Niccoli T, Ridler CE, Clayton EL, Devoy A, Moens T, Norona FE, Woollacott IO, Pietrzyk J, Cleverley K, Nicoll AJ, Pickering-Brown S, Dols J, Cabecinha M, Hendrich O, Fratta P, Fisher EM, Partridge L, Isaacs AM. C9orf72 repeat expansions cause neurodegeneration in Drosophila through arginine-rich proteins. Science 2014; 345:1192-1194. [PMID: 25103406 PMCID: PMC4944841 DOI: 10.1126/science.1256800] [Citation(s) in RCA: 530] [Impact Index Per Article: 53.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
An expanded GGGGCC repeat in C9orf72 is the most common genetic cause of frontotemporal dementia and amyotrophic lateral sclerosis. A fundamental question is whether toxicity is driven by the repeat RNA itself and/or by dipeptide repeat proteins generated by repeat-associated, non-ATG translation. To address this question, we developed in vitro and in vivo models to dissect repeat RNA and dipeptide repeat protein toxicity. Expression of pure repeats, but not stop codon-interrupted "RNA-only" repeats in Drosophila caused adult-onset neurodegeneration. Thus, expanded repeats promoted neurodegeneration through dipeptide repeat proteins. Expression of individual dipeptide repeat proteins with a non-GGGGCC RNA sequence revealed that both poly-(glycine-arginine) and poly-(proline-arginine) proteins caused neurodegeneration. These findings are consistent with a dual toxicity mechanism, whereby both arginine-rich proteins and repeat RNA contribute to C9orf72-mediated neurodegeneration.
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Affiliation(s)
- Sarah Mizielinska
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Sebastian Grönke
- Max Planck Institute for Biology of Ageing, Joseph-Stelzmann-Strasse 9b, 50931 Cologne, Germany
| | - Teresa Niccoli
- Department of Genetics, Evolution and Environment, Institute of Healthy Ageing, UCL, Darwin Building, Gower Street, London WC1E 6BT, UK
| | - Charlotte E. Ridler
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Emma L. Clayton
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Anny Devoy
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Thomas Moens
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
- Department of Genetics, Evolution and Environment, Institute of Healthy Ageing, UCL, Darwin Building, Gower Street, London WC1E 6BT, UK
| | - Frances E. Norona
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Ione O.C. Woollacott
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Julian Pietrzyk
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Karen Cleverley
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Andrew J. Nicoll
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
- MRC Prion Unit, UCL Institute of Neurology, London WC1N 3BG, UK
| | - Stuart Pickering-Brown
- Institute of Brain, Behaviour and Mental Health, Faculty of Human and Medical Sciences, University of Manchester, AV Hill Building, Oxford Road, Manchester, M13 9PT, UK
| | - Jacqueline Dols
- Max Planck Institute for Biology of Ageing, Joseph-Stelzmann-Strasse 9b, 50931 Cologne, Germany
| | - Melissa Cabecinha
- Department of Genetics, Evolution and Environment, Institute of Healthy Ageing, UCL, Darwin Building, Gower Street, London WC1E 6BT, UK
| | - Oliver Hendrich
- Max Planck Institute for Biology of Ageing, Joseph-Stelzmann-Strasse 9b, 50931 Cologne, Germany
| | - Pietro Fratta
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
- MRC Centre for Neuromuscular Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Elizabeth M.C. Fisher
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
- MRC Centre for Neuromuscular Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Linda Partridge
- Max Planck Institute for Biology of Ageing, Joseph-Stelzmann-Strasse 9b, 50931 Cologne, Germany
- Department of Genetics, Evolution and Environment, Institute of Healthy Ageing, UCL, Darwin Building, Gower Street, London WC1E 6BT, UK
| | - Adrian M. Isaacs
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
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Sareen D, O'Rourke JG, Meera P, Muhammad AKMG, Grant S, Simpkinson M, Bell S, Carmona S, Ornelas L, Sahabian A, Gendron T, Petrucelli L, Baughn M, Ravits J, Harms MB, Rigo F, Bennett CF, Otis TS, Svendsen CN, Baloh RH. Targeting RNA foci in iPSC-derived motor neurons from ALS patients with a C9ORF72 repeat expansion. Sci Transl Med 2014; 5:208ra149. [PMID: 24154603 DOI: 10.1126/scitranslmed.3007529] [Citation(s) in RCA: 514] [Impact Index Per Article: 51.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Amyotrophic lateral sclerosis (ALS) is a severe neurodegenerative condition characterized by loss of motor neurons in the brain and spinal cord. Expansions of a hexanucleotide repeat (GGGGCC) in the noncoding region of the C9ORF72 gene are the most common cause of the familial form of ALS (C9-ALS), as well as frontotemporal lobar degeneration and other neurological diseases. How the repeat expansion causes disease remains unclear, with both loss of function (haploinsufficiency) and gain of function (either toxic RNA or protein products) proposed. We report a cellular model of C9-ALS with motor neurons differentiated from induced pluripotent stem cells (iPSCs) derived from ALS patients carrying the C9ORF72 repeat expansion. No significant loss of C9ORF72 expression was observed, and knockdown of the transcript was not toxic to cultured human motor neurons. Transcription of the repeat was increased, leading to accumulation of GGGGCC repeat-containing RNA foci selectively in C9-ALS iPSC-derived motor neurons. Repeat-containing RNA foci colocalized with hnRNPA1 and Pur-α, suggesting that they may be able to alter RNA metabolism. C9-ALS motor neurons showed altered expression of genes involved in membrane excitability including DPP6, and demonstrated a diminished capacity to fire continuous spikes upon depolarization compared to control motor neurons. Antisense oligonucleotides targeting the C9ORF72 transcript suppressed RNA foci formation and reversed gene expression alterations in C9-ALS motor neurons. These data show that patient-derived motor neurons can be used to delineate pathogenic events in ALS.
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Affiliation(s)
- Dhruv Sareen
- Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, CA 90048, USA
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Abstract
Our understanding of amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disease, is expanding rapidly as its genetic causes are uncovered. The pace of new gene discovery over the last 5 years has accelerated, providing new insights into the pathogenesis of disease and highlighting biological pathways as targets for therapeutic development. This article reviews our current understanding of the heritability of ALS and provides an overview of each of the major ALS genes, highlighting their phenotypic characteristics and frequencies as a guide for clinicians evaluating patients with ALS.
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Affiliation(s)
- Matthew B Harms
- Neuromuscular Division, Department of Neurology, Hope Center for Neurological Disorders, Washington University School of Medicine, 660 South Euclid Avenue, St Louis, MO 63110, USA.
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Cooper-Knock J, Walsh MJ, Higginbottom A, Robin Highley J, Dickman MJ, Edbauer D, Ince PG, Wharton SB, Wilson SA, Kirby J, Hautbergue GM, Shaw PJ. Sequestration of multiple RNA recognition motif-containing proteins by C9orf72 repeat expansions. ACTA ACUST UNITED AC 2014; 137:2040-51. [PMID: 24866055 PMCID: PMC4065024 DOI: 10.1093/brain/awu120] [Citation(s) in RCA: 229] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Expansion of GGGGCC repeats in C9orf72 causes familial amyotrophic lateral sclerosis (ALS) and frontotemporal dementia, but the underlying mechanism is unclear. Using RNA pulldown and immunohistochemistry in ALS biosamples, Cooper-Knock et al. identify proteins that bind to the repeat expansions. Disrupted RNA splicing and/or nuclear export may underlie C9orf72-ALS pathogenesis. GGGGCC repeat expansions of C9orf72 represent the most common genetic variant of amyotrophic lateral sclerosis and frontotemporal degeneration, but the mechanism of pathogenesis is unclear. Recent reports have suggested that the transcribed repeat might form toxic RNA foci that sequester various RNA processing proteins. Consensus as to the identity of the binding partners is missing and whole neuronal proteome investigation is needed. Using RNA fluorescence in situ hybridization we first identified nuclear and cytoplasmic RNA foci in peripheral and central nervous system biosamples from patients with amyotrophic lateral sclerosis with a repeat expansion of C9orf72 (C9orf72+), but not from those patients without a repeat expansion of C9orf72 (C9orf72−) or control subjects. Moreover, in the cases examined, the distribution of foci-positive neurons correlated with the clinical phenotype (t-test P < 0.05). As expected, RNA foci are ablated by RNase treatment. Interestingly, we identified foci in fibroblasts from an asymptomatic C9orf72+ carrier. We next performed pulldown assays, with GGGGCC5, in conjunction with mass spectrometry analysis, to identify candidate binding partners of the GGGGCC repeat expansion. Proteins containing RNA recognition motifs and involved in splicing, messenger RNA nuclear export and/or translation were significantly enriched. Immunohistochemistry in central nervous system tissue from C9orf72+ patients with amyotrophic lateral sclerosis demonstrated co-localization of RNA foci with SRSF2, hnRNP H1/F, ALYREF and hnRNP A1 in cerebellar granule cells and with SRSF2, hnRNP H1/F and ALYREF in motor neurons, the primary target of pathology in amyotrophic lateral sclerosis. Direct binding of proteins to GGGGCC repeat RNA was confirmed in vitro by ultraviolet-crosslinking assays. Co-localization was only detected in a small proportion of RNA foci, suggesting dynamic sequestration rather than irreversible binding. Additional immunohistochemistry demonstrated that neurons with and without RNA foci were equally likely to show nuclear depletion of TDP-43 (χ2P = 0.75) or poly-GA dipeptide repeat protein inclusions (χ2P = 0.46). Our findings suggest two non-exclusive pathogenic mechanisms: (i) functional depletion of RNA-processing proteins resulting in disruption of messenger RNA splicing; and (ii) licensing of expanded C9orf72 pre-messenger RNA for nuclear export by inappropriate association with messenger RNA export adaptor protein(s) leading to cytoplasmic repeat associated non-ATG translation and formation of potentially toxic dipeptide repeat protein.
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Affiliation(s)
- Johnathan Cooper-Knock
- 1 Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, 385A Glossop Road, Sheffield S10 2HQ, UK
| | - Matthew J Walsh
- 1 Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, 385A Glossop Road, Sheffield S10 2HQ, UK
| | - Adrian Higginbottom
- 1 Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, 385A Glossop Road, Sheffield S10 2HQ, UK
| | - J Robin Highley
- 1 Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, 385A Glossop Road, Sheffield S10 2HQ, UK
| | - Mark J Dickman
- 2 Chemical and Biological Engineering, ChELSI Institute, University of Sheffield, Mappin Street, Sheffield, S1 3JD, UK
| | - Dieter Edbauer
- 3 DZNE-German Centre for Neurodegenerative Diseases and Munich Cluster of Systems Neurology (SyNergy), Munich, Germany
| | - Paul G Ince
- 1 Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, 385A Glossop Road, Sheffield S10 2HQ, UK
| | - Stephen B Wharton
- 1 Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, 385A Glossop Road, Sheffield S10 2HQ, UK
| | - Stuart A Wilson
- 4 Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Sheffield, S10 2TN, UK
| | - Janine Kirby
- 1 Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, 385A Glossop Road, Sheffield S10 2HQ, UK
| | - Guillaume M Hautbergue
- 1 Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, 385A Glossop Road, Sheffield S10 2HQ, UK
| | - Pamela J Shaw
- 1 Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, 385A Glossop Road, Sheffield S10 2HQ, UK
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47
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Antisense oligonucleotide therapy for the treatment of C9ORF72 ALS/FTD diseases. Mol Neurobiol 2014; 50:721-32. [PMID: 24809691 DOI: 10.1007/s12035-014-8724-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2013] [Accepted: 04/28/2014] [Indexed: 10/25/2022]
Abstract
Motor neuron disorders, and particularly amyotrophic lateral sclerosis (ALS), are fatal diseases that are due to the loss of motor neurons in the brain and spinal cord, with progressive paralysis and premature death. It has been recently shown that the most frequent genetic cause of ALS, frontotemporal dementia (FTD), and other neurological diseases is the expansion of a hexanucleotide repeat (GGGGCC) in the non-coding region of the C9ORF72 gene. The pathogenic mechanisms that produce cell death in the presence of this expansion are still unclear. One of the most likely hypotheses seems to be the gain-of-function that is achieved through the production of toxic RNA (able to sequester RNA-binding protein) and/or toxic proteins. In recent works, different authors have reported that antisense oligonucleotides complementary to the C9ORF72 RNA transcript sequence were able to significantly reduce RNA foci generated by the expanded RNA, in affected cells. Here, we summarize the recent findings that support the idea that the buildup of "toxic" RNA containing the GGGGCC repeat contributes to the death of motor neurons in ALS and also suggest that the use of antisense oligonucleotides targeting this transcript is a promising strategy for treating ALS/frontotemporal lobe dementia (FTLD) patients with the C9ORF72 repeat expansion. These data are particularly important, given the state of the art antisense technology, and they allow researchers to believe that a clinical application of these discoveries will be possible soon.
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48
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Su XW, Broach JR, Connor JR, Gerhard GS, Simmons Z. Genetic heterogeneity of amyotrophic lateral sclerosis: Implications for clinical practice and research. Muscle Nerve 2014; 49:786-803. [DOI: 10.1002/mus.24198] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/29/2014] [Indexed: 12/26/2022]
Affiliation(s)
- Xiaowei W. Su
- Department of Neurosurgery; The Pennsylvania State University College of Medicine; Hershey Pennsylvania USA
| | - James R. Broach
- Department of Biochemistry and Molecular Biology; The Pennsylvania State University College of Medicine; Hershey Pennsylvania USA
| | - James R. Connor
- Department of Neurosurgery; The Pennsylvania State University College of Medicine; Hershey Pennsylvania USA
| | - Glenn S. Gerhard
- Department of Biochemistry and Molecular Biology; The Pennsylvania State University College of Medicine; Hershey Pennsylvania USA
| | - Zachary Simmons
- Department of Neurology; Penn State Milton S. Hershey Medical Center; 30 Hope Drive (Suite EC037) Hershey Pennsylvania 17033 USA
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49
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Yokoyama JS, Sirkis DW, Miller BL. C9ORF72 hexanucleotide repeats in behavioral and motor neuron disease: clinical heterogeneity and pathological diversity. AMERICAN JOURNAL OF NEURODEGENERATIVE DISEASE 2014; 3:1-18. [PMID: 24753999 PMCID: PMC3986607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 03/10/2014] [Indexed: 06/03/2023]
Abstract
Hexanucleotide repeat expansion in C9ORF72 is the most common genetic cause of frontotemporal dementia (FTD), a predominantly behavioral disease, and amyotrophic lateral sclerosis (ALS), a disease of motor neurons. The primary objectives of this review are to highlight the clinical heterogeneity associated with C9ORF72 pathogenic expansion and identify potential molecular mechanisms underlying selective vulnerability of distinct neural populations. The proposed mechanisms by which C9ORF72 expansion causes behavioral and motor neuron disease highlight the emerging role of impaired RNA and protein homeostasis in a spectrum of neurodegeneration and strengthen the biological connection between FTD and ALS.
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Affiliation(s)
| | - Daniel W Sirkis
- Department of Molecular and Cell Biology and Howard Hughes Medical Institute, University of California at BerkeleyBerkeley, CA, USA
| | - Bruce L Miller
- Department of Neurology, University of CaliforniaSan Francisco, CA, USA
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50
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Pliner HA, Mann DM, Traynor BJ. Searching for Grendel: origin and global spread of the C9ORF72 repeat expansion. Acta Neuropathol 2014; 127:391-6. [PMID: 24496499 DOI: 10.1007/s00401-014-1250-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Revised: 01/23/2014] [Accepted: 01/24/2014] [Indexed: 12/11/2022]
Abstract
Recent advances are uncovering more and more of the genetic architecture underlying amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative condition that affects ~6,000 Americans annually. Chief among these was the discovery that a large repeat expansion in the C9ORF72 gene is responsible for an unprecedented portion of familial and sporadic ALS cases. Much has been published on how this expansion disrupts neuronal homeostasis and how gene-based therapy might be an effective treatment in the future. Nevertheless, it is instructive to look back at the origins of this important mutation. In this opinion piece, we attempt to answer three key questions concerning C9ORF72. First, how many times did the expansion occur throughout human history? Second, how old is the expansion? And finally and perhaps most importantly, how did the expansion spread throughout Europe? We speculate that the expansion occurred only once in the past, that this event took place in the Finnish population and that the Vikings and their descendants were responsible for disseminating this mutation throughout the rest of the continent.
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Affiliation(s)
- Hannah A Pliner
- Neuromuscular Diseases Research Unit, Laboratory of Neurogenetics, National Institute on Aging, NIH, Bethesda, MD, 20892, USA
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