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Non-neuronal cells in amyotrophic lateral sclerosis - from pathogenesis to biomarkers. Nat Rev Neurol 2021; 17:333-348. [PMID: 33927394 DOI: 10.1038/s41582-021-00487-8] [Citation(s) in RCA: 75] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/16/2021] [Indexed: 02/04/2023]
Abstract
The prevailing motor neuron-centric view of amyotrophic lateral sclerosis (ALS) pathogenesis could be an important factor in the failure to identify disease-modifying therapy for this neurodegenerative disorder. Non-neuronal cells have crucial homeostatic functions within the CNS and evidence of involvement of these cells in the pathophysiology of several neurodegenerative disorders, including ALS, is accumulating. Microglia and astrocytes, in crosstalk with peripheral immune cells, can exert both neuroprotective and adverse effects, resulting in a highly nuanced range of neuronal and non-neuronal cell interactions. This Review provides an overview of the diverse roles of non-neuronal cells in relation to the pathogenesis of ALS and the emerging potential of non-neuronal cell biomarkers to advance therapeutic development.
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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: 66] [Impact Index Per Article: 22.0] [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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Mini-Review: Induced pluripotent stem cells and the search for new cell-specific ALS therapeutic targets. Neurosci Lett 2021; 755:135911. [PMID: 33892003 DOI: 10.1016/j.neulet.2021.135911] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 04/05/2021] [Accepted: 04/17/2021] [Indexed: 12/30/2022]
Abstract
Amongst the most important discoveries in ALS pathobiology are the works demonstrating that multiple cell types contribute to disease onset and progression. However, a significant limitation in ALS research is the inability to obtain tissues from ALS patient brain and spinal cord during the course of the disease. In vivo modeling has provided insights into the role of these cell subtypes in disease onset and progression. However, in vivo models also have shortcomings, including the reliance on a limited number of models based upon hereditary forms of the disease. Therefore, using human induced pluripotent stem cells (iPSC) reprogrammed from somatic cells of ALS patients, with both hereditary and sporadic forms of the disease, and differentiated into cell subtypes of both the central nervous system (CNS) and peripheral nervous system (PNS), have become powerful complementary tools for investigating basic mechanisms of disease as well as a platform for drug discovery. Motor neuron and other neuron subtypes, as well as non-neuronal cells have been differentiated from human iPSC and studied for their potential contributions to ALS pathobiology. As iPSC technologies have advanced, 3D modeling with multicellular systems organised in microfluidic chambers or organoids are the next step in validating the pathways and therapeutic targets already identified. Precision medicine approaches with iPSC using either traditional strategies of screening drugs that target a known pathogenic mechanism as well as "blind-to-target" drug screenings that allow for patient stratification based on drug response rather than clinical characteristics are now being employed.
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Expression of C9orf72 hexanucleotide repeat expansion leads to formation of RNA foci and dipeptide repeat proteins but does not influence autophagy or proteasomal function in neuronal cells. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2021; 1868:119021. [PMID: 33775797 DOI: 10.1016/j.bbamcr.2021.119021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 03/06/2021] [Accepted: 03/22/2021] [Indexed: 12/22/2022]
Abstract
C9orf72 hexanucleotide repeat expansion (HRE) is the major genetic cause underpinning frontotemporal lobar degeneration (FLTD) and amyotrophic lateral sclerosis (ALS). C9orf72 HRE-associated pathogenesis involves both loss-of-function, through reduced C9orf72 levels, and gain-of-function mechanisms, including formation of RNA foci and generation of dipeptide repeat (DPR) proteins. In addition, dysfunctional protein degradation pathways, i.e. autophagy and ubiquitin-proteasome system (UPS), are suggested. Our aim was to study the gain-of-function mechanisms in the context of the function of protein degradation pathways as well as the regulation of the DPR proteins through these pathways. To this end, we expressed the pathological HRE in neuronal N2a cells and mouse primary cortical neurons. Protein degradation pathways were modulated to induce or block autophagy or to inhibit UPS. In addition, proteasomal activity was assessed. The C9orf72 HRE-expressing N2a cells and neurons were confirmed to produce RNA foci and DPR proteins, predominantly the Poly-GP proteins. However, the presence of these pathological hallmarks did not result in alterations in autophagy or proteasomal activity in either of the studied cell types. In N2a cells, Poly-GP proteins appeared in soluble forms and Lactacystin-mediated UPS inhibition increased their levels, indicating proteasomal regulation. Similar effects were not observed in cortical neurons, where the Poly-GP proteins formed also higher molecular weight forms. These results suggest a cell type-specific morphology and regulation of the DPR proteins. Further studies in other model systems may shed additional light onto the effects of the C9orf72 HRE on cellular protein degradation pathways and the regulation of the DPR protein levels.
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Quezada E, Cappelli C, Diaz I, Jury N, Wightman N, Brown RH, Montecino M, van Zundert B. BET bromodomain inhibitors PFI-1 and JQ1 are identified in an epigenetic compound screen to enhance C9ORF72 gene expression and shown to ameliorate C9ORF72-associated pathological and behavioral abnormalities in a C9ALS/FTD model. Clin Epigenetics 2021; 13:56. [PMID: 33726839 PMCID: PMC7962347 DOI: 10.1186/s13148-021-01039-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Accepted: 02/23/2021] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND An intronic GGGGCC (G4C2) hexanucleotide repeat expansion (HRE) in the C9ORF72 gene is the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), referred to as C9ALS/FTD. No cure or effective treatment exist for C9ALS/FTD. Three major molecular mechanisms have emerged to explain C9ALS/FTD disease mechanisms: (1) C9ORF72 loss-of-function through haploinsufficiency, (2) dipeptide repeat (DPR) proteins mediated toxicity by the translation of the repeat RNAs, and more controversial, (3) RNA-mediated toxicity by bidirectional transcription of the repeats that form intranuclear RNA foci. Recent studies indicate a double-hit pathogenic mechanism in C9ALS/FTD, where reduced C9ORF72 protein levels lead to impaired clearance of toxic DPRs. Here we explored whether pharmacological compounds can revert these pathological hallmarks in vitro and cognitive impairment in a C9ALS/FTD mouse model (C9BAC). We specifically focused our study on small molecule inhibitors targeting chromatin-regulating proteins (epidrugs) with the goal of increasing C9ORF72 gene expression and reduce toxic DPRs. RESULTS We generated luciferase reporter cell lines containing 10 (control) or ≥ 90 (mutant) G4C2 HRE located between exon 1a and 1b of the human C9ORF72 gene. In a screen of 14 different epidrugs targeting bromodomains, chromodomains and histone-modifying enzymes, we found that several bromodomain and extra-terminal domain (BET) inhibitors (BETi), including PFI-1 and JQ1, increased luciferase reporter activity. Using primary cortical cultures from C9BAC mice, we further found that PFI-1 treatment increased the expression of V1-V3 transcripts of the human mutant C9ORF72 gene, reduced poly(GP)-DPR inclusions but enhanced intranuclear RNA foci. We also tested whether JQ1, an BETi previously shown to reach the mouse brain by intraperitoneal (i.p.) injection, can revert behavioral abnormalities in C9BAC mice. Interestingly, it was found that JQ1 administration (daily i.p. administration for 7 days) rescued hippocampal-dependent cognitive deficits in C9BAC mice. CONCLUSIONS Our findings place BET bromodomain inhibitors as a potential therapy for C9ALS/FTD by ameliorating C9ORF72-associated pathological and behavioral abnormalities. Our finding that PFI-1 increases accumulation of intranuclear RNA foci is in agreement with recent data in flies suggesting that nuclear RNA foci can be neuroprotective by sequestering repeat transcripts that result in toxic DPRs.
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Affiliation(s)
- Esteban Quezada
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile
| | - Claudio Cappelli
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile
| | - Iván Diaz
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile
| | - Nur Jury
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile
| | - Nicholas Wightman
- Department of Neurology, University of Massachusetts Medical School (UMMS), Worcester, MA, USA
| | - Robert H Brown
- Department of Neurology, University of Massachusetts Medical School (UMMS), Worcester, MA, USA
| | - Martín Montecino
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile.
- FONDAP Center for Genome Regulation, Santiago, Chile.
| | - Brigitte van Zundert
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile.
- Department of Neurology, University of Massachusetts Medical School (UMMS), Worcester, MA, USA.
- CARE Biomedical Research Center, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile.
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Perkins EM, Burr K, Banerjee P, Mehta AR, Dando O, Selvaraj BT, Suminaite D, Nanda J, Henstridge CM, Gillingwater TH, Hardingham GE, Wyllie DJA, Chandran S, Livesey MR. Altered network properties in C9ORF72 repeat expansion cortical neurons are due to synaptic dysfunction. Mol Neurodegener 2021; 16:13. [PMID: 33663561 PMCID: PMC7931347 DOI: 10.1186/s13024-021-00433-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 02/14/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Physiological disturbances in cortical network excitability and plasticity are established and widespread in amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) patients, including those harbouring the C9ORF72 repeat expansion (C9ORF72RE) mutation - the most common genetic impairment causal to ALS and FTD. Noting that perturbations in cortical function are evidenced pre-symptomatically, and that the cortex is associated with widespread pathology, cortical dysfunction is thought to be an early driver of neurodegenerative disease progression. However, our understanding of how altered network function manifests at the cellular and molecular level is not clear. METHODS To address this we have generated cortical neurons from patient-derived iPSCs harbouring C9ORF72RE mutations, as well as from their isogenic expansion-corrected controls. We have established a model of network activity in these neurons using multi-electrode array electrophysiology. We have then mechanistically examined the physiological processes underpinning network dysfunction using a combination of patch-clamp electrophysiology, immunocytochemistry, pharmacology and transcriptomic profiling. RESULTS We find that C9ORF72RE causes elevated network burst activity, associated with enhanced synaptic input, yet lower burst duration, attributable to impaired pre-synaptic vesicle dynamics. We also show that the C9ORF72RE is associated with impaired synaptic plasticity. Moreover, RNA-seq analysis revealed dysregulated molecular pathways impacting on synaptic function. All molecular, cellular and network deficits are rescued by CRISPR/Cas9 correction of C9ORF72RE. Our study provides a mechanistic view of the early dysregulated processes that underpin cortical network dysfunction in ALS-FTD. CONCLUSION These findings suggest synaptic pathophysiology is widespread in ALS-FTD and has an early and fundamental role in driving altered network function that is thought to contribute to neurodegenerative processes in these patients. The overall importance is the identification of previously unidentified defects in pre and postsynaptic compartments affecting synaptic plasticity, synaptic vesicle stores, and network propagation, which directly impact upon cortical function.
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Affiliation(s)
- Emma M. Perkins
- 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 Discovery Brain Sciences, University of Edinburgh, Edinburgh, EH8 9XD UK
| | - Karen Burr
- 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
- UK Dementia Research Institute at the University of Edinburgh, Edinburgh, EH16 4SB UK
| | - Poulomi Banerjee
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, EH16 4SB UK
- UK Dementia Research Institute at the University of Edinburgh, Edinburgh, EH16 4SB UK
| | - Arpan R. Mehta
- 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
- UK Dementia Research Institute at the University of Edinburgh, Edinburgh, EH16 4SB UK
| | - Owen Dando
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, EH8 9XD UK
- UK Dementia Research Institute at the University of Edinburgh, Edinburgh, EH16 4SB UK
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, EH8 9XD UK
| | - Bhuvaneish T. Selvaraj
- 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
- UK Dementia Research Institute at the University of Edinburgh, Edinburgh, EH16 4SB UK
| | - Daumante Suminaite
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, EH8 9XD UK
| | - Jyoti Nanda
- 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
- UK Dementia Research Institute at the University of Edinburgh, Edinburgh, EH16 4SB UK
| | - Christopher M. Henstridge
- Euan MacDonald Centre for MND Research, University of Edinburgh, Edinburgh, EH16 4SB UK
- Division of Systems Medicine, School of Medicine, University of Dundee, Dundee, DD1 9SY UK
| | - Thomas H. Gillingwater
- Euan MacDonald Centre for MND Research, University of Edinburgh, Edinburgh, EH16 4SB UK
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, EH8 9XD UK
| | - Giles E. Hardingham
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, EH8 9XD UK
- UK Dementia Research Institute at the University of Edinburgh, Edinburgh, EH16 4SB UK
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, EH8 9XD UK
| | - David J. A. Wyllie
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, EH8 9XD UK
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, EH8 9XD UK
- Centre for Brain Development and Repair, inStem, Bangalore, 560065 India
| | - Siddharthan Chandran
- 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
- UK Dementia Research Institute at the University of Edinburgh, Edinburgh, EH16 4SB UK
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, EH8 9XD UK
- Centre for Brain Development and Repair, inStem, Bangalore, 560065 India
| | - Matthew R. Livesey
- Euan MacDonald Centre for MND Research, University of Edinburgh, Edinburgh, EH16 4SB UK
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, EH8 9XD UK
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, EH8 9XD UK
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, S10 2HQ UK
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Vangoor VR, Gomes‐Duarte A, Pasterkamp RJ. Long non-coding RNAs in motor neuron development and disease. J Neurochem 2021; 156:777-801. [PMID: 32970857 PMCID: PMC8048821 DOI: 10.1111/jnc.15198] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 09/11/2020] [Accepted: 09/14/2020] [Indexed: 12/11/2022]
Abstract
Long non-coding RNAs (lncRNAs) are RNAs that exceed 200 nucleotides in length and that are not translated into proteins. Thousands of lncRNAs have been identified with functions in processes such as transcription and translation regulation, RNA processing, and RNA and protein sponging. LncRNAs show prominent expression in the nervous system and have been implicated in neural development, function and disease. Recent work has begun to report on the expression and roles of lncRNAs in motor neurons (MNs). The cell bodies of MNs are located in cortex, brainstem or spinal cord and their axons project into the brainstem, spinal cord or towards peripheral muscles, thereby controlling important functions such as movement, breathing and swallowing. Degeneration of MNs is a pathological hallmark of diseases such as amyotrophic lateral sclerosis and spinal muscular atrophy. LncRNAs influence several aspects of MN development and disruptions in these lncRNA-mediated effects are proposed to contribute to the pathogenic mechanisms underlying MN diseases (MNDs). Accumulating evidence suggests that lncRNAs may comprise valuable therapeutic targets for different MNDs. In this review, we discuss the role of lncRNAs (including circular RNAs [circRNAs]) in the development of MNs, discuss how lncRNAs may contribute to MNDs and provide directions for future research.
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Affiliation(s)
- Vamshidhar R. Vangoor
- Department of Translational NeuroscienceUniversity Medical Center Utrecht Brain CenterUtrecht UniversityUtrechtThe Netherlands
| | - Andreia Gomes‐Duarte
- Department of Translational NeuroscienceUniversity Medical Center Utrecht Brain CenterUtrecht UniversityUtrechtThe Netherlands
| | - R. Jeroen Pasterkamp
- Department of Translational NeuroscienceUniversity Medical Center Utrecht Brain CenterUtrecht UniversityUtrechtThe Netherlands
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Beckers J, Tharkeshwar AK, Van Damme P. C9orf72 ALS-FTD: recent evidence for dysregulation of the autophagy-lysosome pathway at multiple levels. Autophagy 2021; 17:3306-3322. [PMID: 33632058 PMCID: PMC8632097 DOI: 10.1080/15548627.2021.1872189] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are two clinically distinct classes of neurodegenerative disorders. Yet, they share a range of genetic, cellular, and molecular features. Hexanucleotide repeat expansions (HREs) in the C9orf72 gene and the accumulation of toxic protein aggregates in the nervous systems of the affected individuals are among such common features. Though the mechanisms by which HREs cause toxicity is not clear, the toxic gain of function due to transcribed HRE RNA or dipeptide repeat proteins (DPRs) produced by repeat-associated non-AUG translation together with a reduction in C9orf72 expression are proposed as the contributing factors for disease pathogenesis in ALS and FTD. In addition, several recent studies point toward alterations in protein homeostasis as one of the root causes of the disease pathogenesis. In this review, we discuss the effects of the C9orf72 HRE in the autophagy-lysosome pathway based on various recent findings. We suggest that dysfunction of the autophagy-lysosome pathway synergizes with toxicity from C9orf72 repeat RNA and DPRs to drive disease pathogenesis. Abbreviation: ALP: autophagy-lysosome pathway; ALS: amyotrophic lateral sclerosis; AMPK: AMP-activated protein kinase; ATG: autophagy-related; ASO: antisense oligonucleotide; C9orf72: C9orf72-SMCR8 complex subunit; DENN: differentially expressed in normal and neoplastic cells; DPR: dipeptide repeat protein; EIF2A/eIF2α: eukaryotic translation initiation factor 2A; ER: endoplasmic reticulum; FTD: frontotemporal dementia; GAP: GTPase-activating protein; GEF: guanine nucleotide exchange factor; HRE: hexanucleotide repeat expansion; iPSC: induced pluripotent stem cell; ISR: integrated stress response; M6PR: mannose-6-phosphate receptor, cation dependent; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MN: motor neuron; MTORC1: mechanistic target of rapamycin kinase complex 1; ND: neurodegenerative disorder; RAN: repeat-associated non-ATG; RB1CC1/FIP200: RB1 inducible coiled-coil 1; SLC66A1/PQLC2: solute carrier family 66 member 1; SMCR8: SMCR8-C9orf72 complex subunit; SQSTM1/p62: sequestosome 1; STX17: syntaxin 17; TARDBP/TDP-43: TAR DNA binding protein; TBK1: TANK binding kinase 1; TFEB: transcription factor EB; ULK1: unc-51 like autophagy activating kinase 1; UPS: ubiquitin-proteasome system; WDR41: WD repeat domain 41.
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Affiliation(s)
- Jimmy Beckers
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute (LBI), KU Leuven-University of Leuven, Leuven, Belgium.,VIB, Center for Brain & Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - Arun Kumar Tharkeshwar
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute (LBI), KU Leuven-University of Leuven, Leuven, Belgium.,VIB, Center for Brain & Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - Philip Van Damme
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute (LBI), KU Leuven-University of Leuven, Leuven, Belgium.,VIB, Center for Brain & Disease Research, Laboratory of Neurobiology, Leuven, Belgium.,University Hospitals Leuven, Department of Neurology, Leuven, Belgium
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59
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Liu Y, Dodart JC, Tran H, Berkovitch S, Braun M, Byrne M, Durbin AF, Hu XS, Iwamoto N, Jang HG, Kandasamy P, Liu F, Longo K, Ruschel J, Shelke J, Yang H, Yin Y, Donner A, Zhong Z, Vargeese C, Brown RH. Variant-selective stereopure oligonucleotides protect against pathologies associated with C9orf72-repeat expansion in preclinical models. Nat Commun 2021; 12:847. [PMID: 33558503 PMCID: PMC7870851 DOI: 10.1038/s41467-021-21112-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Accepted: 01/08/2021] [Indexed: 12/13/2022] Open
Abstract
A large G4C2-repeat expansion in C9orf72 is the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Neuronal degeneration associated with this expansion arises from a loss of C9orf72 protein, the accumulation of RNA foci, the expression of dipeptide repeat (DPR) proteins, or all these factors. We report the discovery of a new targeting sequence that is common to all C9orf72 transcripts but enables preferential knockdown of repeat-containing transcripts in multiple cellular models and C9BAC transgenic mice. We optimize stereopure oligonucleotides that act through this site, and we demonstrate that their preferential activity depends on both backbone stereochemistry and asymmetric wing design. In mice, stereopure oligonucleotides produce durable depletion of pathogenic signatures without disrupting protein expression. These oligonucleotides selectively protect motor neurons harboring C9orf72-expansion mutation from glutamate-induced toxicity. We hypothesize that targeting C9orf72 with stereopure oligonucleotides may be a viable therapeutic approach for the treatment of C9orf72-associated neurodegenerative disorders.
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Affiliation(s)
| | | | - Helene Tran
- Department of Neurology, University of Massachusetts, Worcester, MA, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | - Yuan Yin
- Wave Life Sciences Ltd., Cambridge, MA, USA
| | - Amy Donner
- Wave Life Sciences Ltd., Cambridge, MA, USA
| | | | | | - Robert H Brown
- Department of Neurology, University of Massachusetts, Worcester, MA, USA
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Ghasemi M, Keyhanian K, Douthwright C. Glial Cell Dysfunction in C9orf72-Related Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Cells 2021; 10:cells10020249. [PMID: 33525344 PMCID: PMC7912327 DOI: 10.3390/cells10020249] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/14/2021] [Accepted: 01/25/2021] [Indexed: 12/17/2022] Open
Abstract
Since the discovery of the chromosome 9 open reading frame 72 (C9orf72) repeat expansion mutation in 2011 as the most common genetic abnormality in amyotrophic lateral sclerosis (ALS, also known as Lou Gehrig's disease) and frontotemporal dementia (FTD), progress in understanding the signaling pathways related to this mutation can only be described as intriguing. Two major theories have been suggested-(i) loss of function or haploinsufficiency and (ii) toxic gain of function from either C9orf72 repeat RNA or dipeptide repeat proteins (DPRs) generated from repeat-associated non-ATG (RAN) translation. Each theory has provided various signaling pathways that potentially participate in the disease progression. Dysregulation of the immune system, particularly glial cell dysfunction (mainly microglia and astrocytes), is demonstrated to play a pivotal role in both loss and gain of function theories of C9orf72 pathogenesis. In this review, we discuss the pathogenic roles of glial cells in C9orf72 ALS/FTD as evidenced by pre-clinical and clinical studies showing the presence of gliosis in C9orf72 ALS/FTD, pathologic hallmarks in glial cells, including TAR DNA-binding protein 43 (TDP-43) and p62 aggregates, and toxicity of C9orf72 glial cells. A better understanding of these pathways can provide new insights into the development of therapies targeting glial cell abnormalities in C9orf72 ALS/FTD.
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Affiliation(s)
- Mehdi Ghasemi
- Correspondence: ; Tel.: +1-774-441-7726; Fax: +1-508-856-4485
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Cihankaya H, Theiss C, Matschke V. Little Helpers or Mean Rogue-Role of Microglia in Animal Models of Amyotrophic Lateral Sclerosis. Int J Mol Sci 2021; 22:ijms22030993. [PMID: 33498186 PMCID: PMC7863915 DOI: 10.3390/ijms22030993] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 01/15/2021] [Accepted: 01/16/2021] [Indexed: 12/13/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is one of the most common neurodegenerative diseases, causing degeneration of both upper and lower motor neurons in the central nervous system (CNS). ALS patients suffer from hyperreflexia, spasticity, paralysis and muscle atrophy and typically die due to respiratory failure 1–5 years after disease onset. In addition to the degeneration of motor neurons on the cellular level, ALS has been associated with neuroinflammation, such as microgliosis. Microglial activation in ALS can either be protective or degenerative to the neurons. Among others, mutations in superoxide dismutase 1 (SOD1), chromosome 9 open reading frame 72 (C9Orf72), transactive response DNA binding protein (TDP) 43 and vacuolar protein sorting-associated protein 54 (VPS54) genes have been associated with ALS. Here, we describe the dual role and functionality of microglia in four different in vivo ALS models and search for the lowest common denominator with respect to the role of microglia in the highly heterogeneous disease of ALS.
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Affiliation(s)
- Hilal Cihankaya
- Department of Cytology, Institute of Anatomy, Ruhr-University Bochum, D-44801 Bochum, Germany; (H.C.); (C.T.)
- International Graduate School of Neuroscience (IGSN), Ruhr-University Bochum, D-44801 Bochum, Germany
| | - Carsten Theiss
- Department of Cytology, Institute of Anatomy, Ruhr-University Bochum, D-44801 Bochum, Germany; (H.C.); (C.T.)
- International Graduate School of Neuroscience (IGSN), Ruhr-University Bochum, D-44801 Bochum, Germany
| | - Veronika Matschke
- Department of Cytology, Institute of Anatomy, Ruhr-University Bochum, D-44801 Bochum, Germany; (H.C.); (C.T.)
- Correspondence: ; Tel.: +49-234-32-25018
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62
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Riemslagh FW, van der Toorn EC, Verhagen RFM, Maas A, Bosman LWJ, Hukema RK, Willemsen R. Inducible expression of human C9ORF72 36x G 4C 2 hexanucleotide repeats is sufficient to cause RAN translation and rapid muscular atrophy in mice. Dis Model Mech 2021; 14:dmm.044842. [PMID: 33431483 PMCID: PMC7903916 DOI: 10.1242/dmm.044842] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 12/17/2020] [Indexed: 12/29/2022] Open
Abstract
The hexanucleotide G4C2 repeat expansion in the first intron of the C9ORF72 gene explains the majority of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) cases. Numerous studies have indicated the toxicity of dipeptide repeats (DPRs) which are produced via repeat-associated non-AUG (RAN) translation from the repeat expansion and accumulate in the brain of C9FTD/ALS patients. Mouse models expressing the human C9ORF72 repeat and/or DPRs show variable pathological, functional, and behavioral characteristics of FTD and ALS. Here, we report a new Tet-on inducible mouse model that expresses 36x pure G4C2 repeats with 100bp upstream and downstream human flanking regions. Brain specific expression causes the formation of sporadic sense DPRs aggregates upon 6 months dox induction but no apparent neurodegeneration. Expression in the rest of the body evokes abundant sense DPRs in multiple organs, leading to weight loss, neuromuscular junction disruption, myopathy, and a locomotor phenotype within the time frame of four weeks. We did not observe any RNA foci or pTDP-43 pathology. Accumulation of DPRs and the myopathy phenotype could be prevented when 36x G4C2 repeat expression was stopped after 1 week. After 2 weeks of expression, the phenotype could not be reversed, even though DPR levels were reduced. In conclusion, expression of 36x pure G4C2 repeats including 100bp human flanking regions is sufficient for RAN translation of sense DPRs and evokes a functional locomotor phenotype. Our inducible mouse model suggests early diagnosis and treatment are important for C9FTD/ALS patients.
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Affiliation(s)
- F W Riemslagh
- Department of Clinical Genetics, Erasmus University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - E C van der Toorn
- Department of Clinical Genetics, Erasmus University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - R F M Verhagen
- Department of Clinical Genetics, Erasmus University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - A Maas
- Department of Cell Biology, Erasmus University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - L W J Bosman
- Department of Neuroscience, Erasmus University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - R K Hukema
- Department of Clinical Genetics, Erasmus University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - R Willemsen
- Department of Clinical Genetics, Erasmus University Medical Center Rotterdam, Rotterdam, The Netherlands
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63
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Pattamatta A, Nguyen L, Olafson HR, Scotti MM, Laboissonniere LA, Richardson J, Berglund JA, Zu T, Wang ET, Ranum LPW. Repeat length increases disease penetrance and severity in C9orf72 ALS/FTD BAC transgenic mice. Hum Mol Genet 2020; 29:3900-3918. [PMID: 33378537 DOI: 10.1093/hmg/ddaa279] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 11/14/2020] [Accepted: 12/23/2020] [Indexed: 12/12/2022] Open
Abstract
C9orf72 ALS/FTD patients show remarkable clinical heterogeneity, but the complex biology of the repeat expansion mutation has limited our understanding of the disease. BAC transgenic mice were used to better understand the molecular mechanisms and repeat length effects of C9orf72 ALS/FTD. Genetic analyses of these mice demonstrate that the BAC transgene and not integration site effects cause ALS/FTD phenotypes. Transcriptomic changes in cell proliferation, inflammation and neuronal pathways are found late in disease and alternative splicing changes provide early molecular markers that worsen with disease progression. Isogenic sublines of mice with 800, 500 or 50 G4C2 repeats generated from the single-copy C9-500 line show longer repeats result in earlier onset, increased disease penetrance and increased levels of RNA foci and dipeptide RAN protein aggregates. These data demonstrate G4C2 repeat length is an important driver of disease and identify alternative splicing changes as early biomarkers of C9orf72 ALS/FTD.
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Affiliation(s)
- Amrutha Pattamatta
- Center for NeuroGenetics, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,Department of Molecular Genetics and Microbiology, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,University of Florida Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - Lien Nguyen
- Center for NeuroGenetics, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,Department of Molecular Genetics and Microbiology, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,University of Florida Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - Hailey R Olafson
- Center for NeuroGenetics, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,Department of Molecular Genetics and Microbiology, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,University of Florida Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - Marina M Scotti
- Center for NeuroGenetics, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,Department of Molecular Genetics and Microbiology, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,University of Florida Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - Lauren A Laboissonniere
- Center for NeuroGenetics, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,Department of Molecular Genetics and Microbiology, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,University of Florida Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - Jared Richardson
- Center for NeuroGenetics, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,University of Florida Genetics Institute, University of Florida, Gainesville, FL 32610, USA.,McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA
| | - J Andrew Berglund
- Center for NeuroGenetics, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,Department of Biochemistry and Molecular Biology, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,RNA Institute and Department of Biological Sciences, University at Albany, Albany, NY 12222, USA
| | - Tao Zu
- Center for NeuroGenetics, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,Department of Molecular Genetics and Microbiology, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,University of Florida Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - Eric T Wang
- Center for NeuroGenetics, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,Department of Molecular Genetics and Microbiology, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,University of Florida Genetics Institute, University of Florida, Gainesville, FL 32610, USA.,McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA
| | - Laura P W Ranum
- Center for NeuroGenetics, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,Department of Molecular Genetics and Microbiology, Colllege of Medicine, University of Florida, Gainesville, FL 32610, USA.,University of Florida Genetics Institute, University of Florida, Gainesville, FL 32610, USA.,McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA.,Fixel Institute, University of Florida, Gainesville, FL 32610, USA
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64
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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: 6] [Impact Index Per Article: 1.5] [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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65
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Shabir O, Moll TA, Matuszyk MM, Eyre B, Dake MD, Berwick J, Francis SE. Preclinical models of disease and multimorbidity with focus upon cardiovascular disease and dementia. Mech Ageing Dev 2020; 192:111361. [DOI: 10.1016/j.mad.2020.111361] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 08/28/2020] [Accepted: 09/16/2020] [Indexed: 12/12/2022]
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Castro AF, Loureiro JR, Bessa J, Silveira I. Antisense Transcription across Nucleotide Repeat Expansions in Neurodegenerative and Neuromuscular Diseases: Progress and Mysteries. Genes (Basel) 2020; 11:E1418. [PMID: 33261024 PMCID: PMC7760973 DOI: 10.3390/genes11121418] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 11/24/2020] [Accepted: 11/24/2020] [Indexed: 12/14/2022] Open
Abstract
Unstable repeat expansions and insertions cause more than 30 neurodegenerative and neuromuscular diseases. Remarkably, bidirectional transcription of repeat expansions has been identified in at least 14 of these diseases. More remarkably, a growing number of studies has been showing that both sense and antisense repeat RNAs are able to dysregulate important cellular pathways, contributing together to the observed clinical phenotype. Notably, antisense repeat RNAs from spinocerebellar ataxia type 7, myotonic dystrophy type 1, Huntington's disease and frontotemporal dementia/amyotrophic lateral sclerosis associated genes have been implicated in transcriptional regulation of sense gene expression, acting either at a transcriptional or posttranscriptional level. The recent evidence that antisense repeat RNAs could modulate gene expression broadens our understanding of the pathogenic pathways and adds more complexity to the development of therapeutic strategies for these disorders. In this review, we cover the amazing progress made in the understanding of the pathogenic mechanisms associated with repeat expansion neurodegenerative and neuromuscular diseases with a focus on the impact of antisense repeat transcription in the development of efficient therapies.
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Affiliation(s)
- Ana F. Castro
- Genetics of Cognitive Dysfunction Laboratory, i3S- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal; (A.F.C.); (J.R.L.)
- IBMC-Institute for Molecular and Cell Biology, Universidade do Porto, 4200-135 Porto, Portugal;
- ICBAS, Universidade do Porto, 4050-313 Porto, Portugal
| | - Joana R. Loureiro
- Genetics of Cognitive Dysfunction Laboratory, i3S- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal; (A.F.C.); (J.R.L.)
- IBMC-Institute for Molecular and Cell Biology, Universidade do Porto, 4200-135 Porto, Portugal;
| | - José Bessa
- IBMC-Institute for Molecular and Cell Biology, Universidade do Porto, 4200-135 Porto, Portugal;
- Vertebrate Development and Regeneration Laboratory, i3S- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal
| | - Isabel Silveira
- Genetics of Cognitive Dysfunction Laboratory, i3S- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal; (A.F.C.); (J.R.L.)
- IBMC-Institute for Molecular and Cell Biology, Universidade do Porto, 4200-135 Porto, Portugal;
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67
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Gittings LM, Sattler R. Recent advances in understanding amyotrophic lateral sclerosis and emerging therapies. Fac Rev 2020; 9:12. [PMID: 33659944 PMCID: PMC7886072 DOI: 10.12703/b/9-12] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that is characterized by degeneration of both upper and lower motor neurons and subsequent progressive loss of muscle function. Within the last decade, significant progress has been made in the understanding of the etiology and pathobiology of the disease; however, treatment options remain limited and only two drugs, which exert a modest effect on survival, are approved for ALS treatment in the US. Therefore, the search for effective ALS therapies continues, and over 60 clinical trials are in progress for patients with ALS and other therapeutics are at the pre-clinical stage of development. Recent advances in understanding the genetics, pathology, and molecular mechanisms of ALS have led to the identification of novel targets and strategies that are being used in emerging ALS therapeutic interventions. Here, we review the current status and mechanisms of action of a selection of emerging ALS therapies in pre-clinical or early clinical development, including gene therapy, immunotherapy, and strategies that target neuroinflammation, phase separation, and protein clearance.
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Affiliation(s)
- Lauren M Gittings
- Department of Neurobiology, Barrow Neurological Institute, Phoenix, AZ, USA
| | - Rita Sattler
- Department of Neurobiology, Barrow Neurological Institute, Phoenix, AZ, USA
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68
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Survival and Motor Phenotypes in FVB C9-500 ALS/FTD BAC Transgenic Mice Reproduced by Multiple Labs. Neuron 2020; 108:784-796.e3. [PMID: 33022226 DOI: 10.1016/j.neuron.2020.09.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 05/14/2020] [Accepted: 09/04/2020] [Indexed: 01/21/2023]
Abstract
Mordes et al. (2020) did not detect the survival or motor phenotypes in C9orf72 BAC transgenic mice originally described by Liu et al. (2016). We discuss methodological differences between the Mordes and Liu studies, several additional studies in which survival and motor phenotypes were found, and possible environmental and genetic effects. First, Nguyen et al. (2020) showed robust ALS/FTD phenotypes in C9-BAC versus non-transgenic (NT) mice and that α-GA1 treatment improved survival, behavior, and neurodegeneration. The groups of Gelbard and Saxena also show decreased survival of C9-BAC versus NT mice and neuropathological and behavioral deficits similar to those shown by Liu et al. (2016). Although FVB/N mice can have seizures, increases in seizure severity and death of C9 and NT animals, which may mask C9 disease phenotypes, have been observed in recent C9-500 FVB/NJ-bred cohorts. In summary, we provide an update on phenotypes seen in FVB C9-BAC mice and additional details to successfully use this model. This Matters Arising Response paper addresses the Mordes et al. (2020) Matters Arising paper, published concurrently in Neuron.
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69
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Absence of Survival and Motor Deficits in 500 Repeat C9ORF72 BAC Mice. Neuron 2020; 108:775-783.e4. [PMID: 33022228 DOI: 10.1016/j.neuron.2020.08.009] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 05/06/2020] [Accepted: 08/11/2020] [Indexed: 12/28/2022]
Abstract
A hexanucleotide repeat expansion at C9ORF72 is the most common genetic cause of amyotrophic lateral sclerosis (ALS)/frontotemporal dementia (FTD). Initial studies of bacterial artificial chromosome (BAC) transgenic mice harboring this expansion described an absence of motor and survival phenotypes. However, a recent study by Liu and colleagues described transgenic mice harboring a large repeat expansion (C9-500) and reported decreased survival and progressive motor phenotypes. To determine the utility of the C9-500 animals for understanding degenerative mechanisms, we validated and established two independent colonies of transgene carriers. However, extended studies of these animals for up to 1 year revealed no reproducible abnormalities in survival, motor function, or neurodegeneration. Here, we propose several potential explanations for the disparate nature of our findings from those of Liu and colleagues. Resolving the discrepancies we identify will be essential to settle the translational utility of C9-500 mice. This Matters Arising paper is in response to Liu et al. (2016), published in Neuron. See also the response by Nguyen et al. (2020), published in this issue.
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70
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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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71
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Yang Q, Jiao B, Shen L. The Development of C9orf72-Related Amyotrophic Lateral Sclerosis and Frontotemporal Dementia Disorders. Front Genet 2020; 11:562758. [PMID: 32983232 PMCID: PMC7492664 DOI: 10.3389/fgene.2020.562758] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Accepted: 08/12/2020] [Indexed: 12/12/2022] Open
Abstract
The expanded GGGGCC hexanucleotide repeat in the non-coding region of the C9orf72 gene is the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). There are three main disease mechanisms: loss of function of C9ORF72 protein, gain of function from the accumulation of sense and antisense (GGGGCC)n in RNA, and from the production of toxic dipeptides repeat proteins (DPRs) by non-AUG initiated translation. While many of the downstream mechanisms have been identified, the specific pathogenic pathway is still unclear. In this article, we provide an overview on the currently available literature and propose several hypotheses: (1) The pathogenesis of C9orf72-associated ALS/FTD, which cannot be explained by a single mechanism, involves a dual mechanism of both loss and gain of function. (2) The loss of function and gain of function can cause TDP-43 aggregation and damage nucleocytoplasmic transport. (3) Neurodegeneration can be caused by an accumulation of toxic substances in neurons themselves. In addition, we suggest that microglia may cause neurodegeneration by releasing inflammatory factors to neurons. Finally, we summarize several of the most promising treatment strategies.
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Affiliation(s)
- Qijie Yang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Bin Jiao
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Central South University, Changsha, China
| | - Lu Shen
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Central South University, Changsha, China
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Herrando-Grabulosa M, Gaja-Capdevila N, Vela JM, Navarro X. Sigma 1 receptor as a therapeutic target for amyotrophic lateral sclerosis. Br J Pharmacol 2020; 178:1336-1352. [PMID: 32761823 DOI: 10.1111/bph.15224] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 07/13/2020] [Accepted: 07/25/2020] [Indexed: 12/13/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is an adult disease causing a progressive loss of upper and lower motoneurons, muscle paralysis and early death. ALS has a poor prognosis of 3-5 years after diagnosis with no effective cure. The aetiopathogenic mechanisms involved include glutamate excitotoxicity, oxidative stress, protein misfolding, mitochondrial alterations, disrupted axonal transport and inflammation. Sigma non-opioid intracellular receptor 1 (sigma 1 receptor) is a protein expressed in motoneurons, mainly found in the endoplasmic reticulum (ER) on the mitochondria-associated ER membrane (MAM) or in close contact with cholinergic postsynaptic sites. MAMs are sites that allow the assembly of several complexes implicated in essential survival cell functions. The sigma 1 receptor modulates essential mechanisms for motoneuron survival including excitotoxicity, calcium homeostasis, ER stress and mitochondrial dysfunction. This review updates sigma 1 receptor mechanisms and its alterations in ALS, focusing on MAM modulation, which may constitute a novel target for therapeutic strategies. LINKED ARTICLES: This article is part of a themed issue on Neurochemistry in Japan. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.6/issuetoc.
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Affiliation(s)
- Mireia Herrando-Grabulosa
- Institute of Neurosciences, Department Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, Bellaterra, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Núria Gaja-Capdevila
- Institute of Neurosciences, Department Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, Bellaterra, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - José M Vela
- Esteve Pharmaceuticals S.A., Drug Discovery and Preclinical Development, Barcelona, Spain
| | - Xavier Navarro
- Institute of Neurosciences, Department Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, Bellaterra, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.,Institut Guttmann de Neurorehabilitació, Badalona, Spain
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Dong W, Zhang L, Sun C, Gao X, Guan F, Li J, Chen W, Ma Y, Zhang L. Knock in of a hexanucleotide repeat expansion in the C9orf72 gene induces ALS in rats. Animal Model Exp Med 2020; 3:237-244. [PMID: 33024945 PMCID: PMC7529333 DOI: 10.1002/ame2.12129] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 07/07/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND The GGGGCC (G4C2) repeat expansion in the human open reading frame 72 on chromosome 9, C9orf72, is the most common cause of amyotrophic lateral sclerosis (ALS). Studies in transgenic mouse models have linked the pathogenic mechanism of G4C2 repeat expansion to RNA foci or the accumulation of unnatural dipeptide repeats in neurons. However, only one of the existing transgenic mouse lines developed typical ALS. METHODS C9orf72 knockin rats were generated by knockin of 80 G4C2 repeats with human flanking fragments within exon1a and exon1b at the rat C9orf72 locus. Protein expression was detected by western blot. Motor coordination and grip force were measured using a Rotarod test and a grip strength test. Neurodegeneration was assessed by Nissl staining with cresyl violet. RESULTS C9orf72 haploinsufficiency reduced C9orf72 protein expression 40% in the cerebrum, cerebellum and spinal cords from knockin rats (P < .05). The knockin (KI) rats developed motor deficits from 4 months of age. Their falling latencies and grip force were decreased by 67% (P < .01) and 44% (P < .01), respectively, at 12 months of age compared to wild-type (WT) mice. The knockin of the hexanucleotide repeat expansion (HRE) caused a 47% loss of motor neurons in the spinal cord (P < .001) and 25% (5/20) of female KI rats developed hind limb paralysis at 13 to 24 months. CONCLUSION Motor defects in KI rats may result from neurotoxicity caused by HRE and the resulting reduction in C9orf72 protein due to haploinsufficiency. These KI rats could be a useful model for investigating the contributions of loss-of-function to neurotoxicity in C9orf72-related ALS.
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Affiliation(s)
- Wei Dong
- Key Laboratory of Human Disease Comparative MedicineNational Health Commission of China (NHC)Institute of Laboratory Animal SciencePeking Union Medicine CollegeChinese Academy of Medical SciencesBeijingChina
- Neuroscience CenterChinese Academy of Medical SciencesBeijingChina
| | - Li Zhang
- Neuroscience CenterChinese Academy of Medical SciencesBeijingChina
- Beijing Engineering Research Center for Experimental Animal Models of Human DiseasesInstitute of Laboratory Animal SciencePeking Union Medicine CollegeChinese Academy of Medical SciencesBeijingChina
| | - Caixian Sun
- Key Laboratory of Human Disease Comparative MedicineNational Health Commission of China (NHC)Institute of Laboratory Animal SciencePeking Union Medicine CollegeChinese Academy of Medical SciencesBeijingChina
| | - Xiang Gao
- Key Laboratory of Human Disease Comparative MedicineNational Health Commission of China (NHC)Institute of Laboratory Animal SciencePeking Union Medicine CollegeChinese Academy of Medical SciencesBeijingChina
| | - Feifei Guan
- Key Laboratory of Human Disease Comparative MedicineNational Health Commission of China (NHC)Institute of Laboratory Animal SciencePeking Union Medicine CollegeChinese Academy of Medical SciencesBeijingChina
| | - Jing Li
- Beijing Engineering Research Center for Experimental Animal Models of Human DiseasesInstitute of Laboratory Animal SciencePeking Union Medicine CollegeChinese Academy of Medical SciencesBeijingChina
| | - Wei Chen
- Key Laboratory of Human Disease Comparative MedicineNational Health Commission of China (NHC)Institute of Laboratory Animal SciencePeking Union Medicine CollegeChinese Academy of Medical SciencesBeijingChina
| | - Yuanwu Ma
- Beijing Engineering Research Center for Experimental Animal Models of Human DiseasesInstitute of Laboratory Animal SciencePeking Union Medicine CollegeChinese Academy of Medical SciencesBeijingChina
| | - Lianfeng Zhang
- Key Laboratory of Human Disease Comparative MedicineNational Health Commission of China (NHC)Institute of Laboratory Animal SciencePeking Union Medicine CollegeChinese Academy of Medical SciencesBeijingChina
- Neuroscience CenterChinese Academy of Medical SciencesBeijingChina
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74
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Hao Z, Wang R, Ren H, Wang G. Role of the C9ORF72 Gene in the Pathogenesis of Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Neurosci Bull 2020; 36:1057-1070. [PMID: 32860626 DOI: 10.1007/s12264-020-00567-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2020] [Accepted: 04/30/2020] [Indexed: 12/12/2022] Open
Abstract
Since the discovery of the C9ORF72 gene in 2011, great advances have been achieved in its genetics and in identifying its role in disease models and pathological mechanisms; it is the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). ALS patients with C9ORF72 expansion show heterogeneous symptoms. Those who are C9ORF72 expansion carriers have shorter survival after disease onset than non-C9ORF72 expansion patients. Pathological and clinical features of C9ORF72 patients have been well mimicked via several models, including induced pluripotent stem cell-derived neurons and transgenic mice that were embedded with bacterial artificial chromosome construct and that overexpressing dipeptide repeat proteins. The mechanisms implicated in C9ORF72 pathology include DNA damage, changes of RNA metabolism, alteration of phase separation, and impairment of nucleocytoplasmic transport, which may underlie C9ORF72 expansion-related ALS/FTD and provide insight into non-C9ORF72 expansion-related ALS, FTD, and other neurodegenerative diseases.
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Affiliation(s)
- Zongbing Hao
- Laboratory of Molecular Neuropathology, Jiangsu Key Laboratory of Neuropsychiatric Diseases and Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, 215123, China
| | - Rui Wang
- Laboratory of Molecular Neuropathology, Jiangsu Key Laboratory of Neuropsychiatric Diseases and Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, 215123, China
| | - Haigang Ren
- Laboratory of Molecular Neuropathology, Jiangsu Key Laboratory of Neuropsychiatric Diseases and Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, 215123, China
| | - Guanghui Wang
- Laboratory of Molecular Neuropathology, Jiangsu Key Laboratory of Neuropsychiatric Diseases and Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, 215123, China.
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75
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Dong W, Ma Y, Guan F, Zhang X, Chen W, Zhang L, Zhang L. Ablation of C9orf72 together with excitotoxicity induces ALS in rats. FEBS J 2020; 288:1712-1723. [PMID: 32745320 DOI: 10.1111/febs.15501] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 05/19/2020] [Accepted: 07/28/2020] [Indexed: 12/12/2022]
Abstract
Pathogenesis of familial amyotrophic lateral sclerosis (ALS) linked to expansion of the chromosome 9 open reading frame 72 (C9orf72) hexanucleotide repeat that impairs C9orf72 expression. Loss of function of the C9orf72 protein is one of the three main proposed C9orf72-related ALS mechanisms. However, C9orf72 loss of function, by itself, is insufficient to cause severe phenotypes in mice. Excitotoxicity is another major disease mechanism of ALS. We speculate that loss of C9orf72 protein might cause ALS in combination with excitotoxicity. To date, the effect of C9orf72 deficiency in the background of SD rat has not been examined. To test our hypothesis, we generated a line of rat with a deletion of part of the C9orf72 gene ablating the encoded protein. These animals did not develop any ALS phenotypes; however, when they were treated with kainic acid, an excitotoxicity inducer, the rats developed motor deficits and showed loss of motor neurons (MNs), Golgi complex fragmentation, and abnormal vesicle trafficking. RNA sequencing revealed profound changes in the gene profiles that were primarily associated with neural activity. Our results demonstrated that C9orf72 ablation alone was not enough to cause ALS pathogenesis in rat; but the ablation sensitized MNs to other risk factors that synergistically caused the ALS. These results support a loss of function of C9orf72 mechanism of ALS.
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Affiliation(s)
- Wei Dong
- Key Laboratory of Human Disease Comparative Medicine, National Health Commission of China (NHC), Institute of Laboratory Animal Science, Peking Union Medicine College, Chinese Academy of Medical Sciences, Beijing, China.,Neuroscience Center, Chinese Academy of Medical Sciences, Beijing, China
| | - Yuanwu Ma
- Neuroscience Center, Chinese Academy of Medical Sciences, Beijing, China.,Beijing Engineering Research Center for Experimental Animal Models of Human Diseases, Institute of Laboratory Animal Science, Peking Union Medicine College, Chinese Academy of Medical Sciences, Beijing, China
| | - Feifei Guan
- Key Laboratory of Human Disease Comparative Medicine, National Health Commission of China (NHC), Institute of Laboratory Animal Science, Peking Union Medicine College, Chinese Academy of Medical Sciences, Beijing, China
| | - Xu Zhang
- Beijing Engineering Research Center for Experimental Animal Models of Human Diseases, Institute of Laboratory Animal Science, Peking Union Medicine College, Chinese Academy of Medical Sciences, Beijing, China
| | - Wei Chen
- Key Laboratory of Human Disease Comparative Medicine, National Health Commission of China (NHC), Institute of Laboratory Animal Science, Peking Union Medicine College, Chinese Academy of Medical Sciences, Beijing, China
| | - Li Zhang
- Beijing Engineering Research Center for Experimental Animal Models of Human Diseases, Institute of Laboratory Animal Science, Peking Union Medicine College, Chinese Academy of Medical Sciences, Beijing, China
| | - Lianfeng Zhang
- Key Laboratory of Human Disease Comparative Medicine, National Health Commission of China (NHC), Institute of Laboratory Animal Science, Peking Union Medicine College, Chinese Academy of Medical Sciences, Beijing, China.,Neuroscience Center, Chinese Academy of Medical Sciences, Beijing, China
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76
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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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77
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Solomon DA, Mitchell JC, Salcher-Konrad MT, Vance CA, Mizielinska S. Review: Modelling the pathology and behaviour of frontotemporal dementia. Neuropathol Appl Neurobiol 2020; 45:58-80. [PMID: 30582188 DOI: 10.1111/nan.12536] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 12/16/2018] [Indexed: 12/11/2022]
Abstract
Frontotemporal dementia (FTD) encompasses a collection of clinically and pathologically diverse neurological disorders. Clinical features of behavioural and language dysfunction are associated with neurodegeneration, predominantly of frontal and temporal cortices. Over the past decade, there have been significant advances in the understanding of the genetic aetiology and neuropathology of FTD which have led to the creation of various disease models to investigate the molecular pathways that contribute to disease pathogenesis. The generation of in vivo models of FTD involves either targeting genes with known disease-causative mutations such as GRN and C9orf72 or genes encoding proteins that form the inclusions that characterize the disease pathologically, such as TDP-43 and FUS. This review provides a comprehensive summary of the different in vivo model systems used to understand pathomechanisms in FTD, with a focus on disease models which reproduce aspects of the wide-ranging behavioural phenotypes seen in people with FTD. We discuss the emerging disease pathways that have emerged from these in vivo models and how this has shaped our understanding of disease mechanisms underpinning FTD. We also discuss the challenges of modelling the complex clinical symptoms shown by people with FTD, the confounding overlap with features of motor neuron disease, and the drive to make models more disease-relevant. In summary, in vivo models can replicate many pathological and behavioural aspects of clinical FTD, but robust and thorough investigations utilizing shared features and variability between disease models will improve the disease-relevance of findings and thus better inform therapeutic development.
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Affiliation(s)
- D A Solomon
- UK Dementia Research Institute, King's College London, London, Camberwell, UK.,Department of Basic & Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, London, Camberwell, UK
| | - J C Mitchell
- Department of Basic & Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, London, Camberwell, UK
| | - M-T Salcher-Konrad
- Department of Basic & Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, London, Camberwell, UK
| | - C A Vance
- Department of Basic & Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, London, Camberwell, UK
| | - S Mizielinska
- UK Dementia Research Institute, King's College London, London, Camberwell, UK.,Department of Basic & Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, London, Camberwell, UK
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78
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Nair RR, Tibbit C, Thompson D, McLeod R, Nakhuda A, Simon MM, Baloh RH, Fisher EMC, Isaacs AM, Cunningham TJ. Sizing, stabilising, and cloning repeat-expansions for gene targeting constructs. Methods 2020; 191:15-22. [PMID: 32721467 PMCID: PMC8215685 DOI: 10.1016/j.ymeth.2020.07.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 06/15/2020] [Accepted: 07/16/2020] [Indexed: 11/29/2022] Open
Abstract
Large GGGGCC repeat expansions within BAC vectors are highly unstable. CRISPR-Cas9 screening of BAC vector clones to determine repeat length. CRISPR-Cas9 cloning of GGGGCC repeat expansion regions into the linear pJazz vector. pJazz dramatically stabilizes GGGGCC repeat expansions over 4 kb in length.
Aberrant microsatellite repeat-expansions at specific loci within the human genome cause several distinct, heritable, and predominantly neurological, disorders. Creating models for these diseases poses a challenge, due to the instability of such repeats in bacterial vectors, especially with large repeat expansions. Designing constructs for more precise genome engineering projects, such as engineering knock-in mice, proves a greater challenge still, since these unstable repeats require numerous cloning steps in order to introduce homology arms or selection cassettes. Here, we report our efforts to clone a large hexanucleotide repeat in the C9orf72 gene, originating from within a BAC construct, derived from a C9orf72-ALS patient. We provide detailed methods for efficient repeat sizing and growth conditions in bacteria to facilitate repeat retention during growth and sub-culturing. We report that sub-cloning into a linear vector dramatically improves stability, but is dependent on the relative orientation of DNA replication through the repeat, consistent with previous studies. We envisage the findings presented here provide a relatively straightforward route to maintaining large-range microsatellite repeat-expansions, for efficient cloning into vectors.
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Affiliation(s)
- Remya R Nair
- Mammalian Genetics Unit, MRC Harwell Institute, Oxfordshire OX11 0RD, UK
| | - Charlotte Tibbit
- Mammalian Genetics Unit, MRC Harwell Institute, Oxfordshire OX11 0RD, UK
| | - David Thompson
- Mammalian Genetics Unit, MRC Harwell Institute, Oxfordshire OX11 0RD, UK
| | - Ross McLeod
- Mammalian Genetics Unit, MRC Harwell Institute, Oxfordshire OX11 0RD, UK
| | - Asif Nakhuda
- Mammalian Genetics Unit, MRC Harwell Institute, Oxfordshire OX11 0RD, UK
| | - Michelle M Simon
- Mammalian Genetics Unit, MRC Harwell Institute, Oxfordshire OX11 0RD, UK
| | - Robert H Baloh
- Board of Governors Regenerative Medicine Institute, Los Angeles, CA, USA; Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Elizabeth M C Fisher
- Department of Neuromuscular Diseases, UCL Institute of Neurology, London WC1N 3BG, UK
| | - Adrian M Isaacs
- Department of Neurodegenerative Disease, UCL Institute of Neurology, London WC1N 3BG, UK; UK Dementia Research Institute at UCL, UCL Institute of Neurology, London WC1N 3BG, UK
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79
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Ranganathan R, Haque S, Coley K, Shepheard S, Cooper-Knock J, Kirby J. Multifaceted Genes in Amyotrophic Lateral Sclerosis-Frontotemporal Dementia. Front Neurosci 2020; 14:684. [PMID: 32733193 PMCID: PMC7358438 DOI: 10.3389/fnins.2020.00684] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 06/04/2020] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis and frontotemporal dementia are two progressive, adult onset neurodegenerative diseases, caused by the cell death of motor neurons in the motor cortex and spinal cord and cortical neurons in the frontal and temporal lobes, respectively. Whilst these have previously appeared to be quite distinct disorders, in terms of areas affected and clinical symptoms, identification of cognitive dysfunction as a component of amyotrophic lateral sclerosis (ALS), with some patients presenting with both ALS and FTD, overlapping features of neuropathology and the ongoing discoveries that a significant proportion of the genes underlying the familial forms of the disease are the same, has led to ALS and FTD being described as a disease spectrum. Many of these genes encode proteins in common biological pathways including RNA processing, autophagy, ubiquitin proteasome system, unfolded protein response and intracellular trafficking. This article provides an overview of the ALS-FTD genes before summarizing other known ALS and FTD causing genes where mutations have been found primarily in patients of one disease and rarely in the other. In discussing these genes, the review highlights the similarity of biological pathways in which the encoded proteins function and the interactions that occur between these proteins, whilst recognizing the distinctions of MAPT-related FTD and SOD1-related ALS. However, mutations in all of these genes result in similar pathology including protein aggregation and neuroinflammation, highlighting that multiple different mechanisms lead to common downstream effects and neuronal loss. Next generation sequencing has had a significant impact on the identification of genes associated with both diseases, and has also highlighted the widening clinical phenotypes associated with variants in these ALS and FTD genes. It is hoped that the large sequencing initiatives currently underway in ALS and FTD will begin to uncover why different diseases are associated with mutations within a single gene, especially as a personalized medicine approach to therapy, based on a patient's genetics, approaches the clinic.
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Affiliation(s)
- Ramya Ranganathan
- Sheffield Institute for Translational Neuroscience (SITraN), The University of Sheffield, Sheffield, United Kingdom
| | - Shaila Haque
- Sheffield Institute for Translational Neuroscience (SITraN), The University of Sheffield, Sheffield, United Kingdom
- Department of Biochemistry and Biotechnology, University of Barishal, Barishal, Bangladesh
| | - Kayesha Coley
- Sheffield Institute for Translational Neuroscience (SITraN), The University of Sheffield, Sheffield, United Kingdom
| | - Stephanie Shepheard
- Sheffield Institute for Translational Neuroscience (SITraN), The University of Sheffield, Sheffield, United Kingdom
| | - Johnathan Cooper-Knock
- Sheffield Institute for Translational Neuroscience (SITraN), The University of Sheffield, Sheffield, United Kingdom
| | - Janine Kirby
- Sheffield Institute for Translational Neuroscience (SITraN), The University of Sheffield, Sheffield, United Kingdom
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80
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Tang X, Toro A, T G S, Gao J, Chalk J, Oskarsson B, Zhang K. Divergence, Convergence, and Therapeutic Implications: A Cell Biology Perspective of C9ORF72-ALS/FTD. Mol Neurodegener 2020; 15:34. [PMID: 32513219 PMCID: PMC7282082 DOI: 10.1186/s13024-020-00383-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Accepted: 05/26/2020] [Indexed: 12/12/2022] Open
Abstract
Ever since a GGGGCC hexanucleotide repeat expansion mutation in C9ORF72 was identified as the most common cause of familial amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), three competing but nonexclusive hypotheses to explain how this mutation causes diseases have been proposed and are still under debate. Recent studies in the field have tried to understand how the repeat expansion disrupts cellular physiology, which has suggested interesting convergence of these hypotheses on downstream, functional defects in cells, such as nucleocytoplasmic transport disruption, membrane-less organelle defects, and DNA damage. These studies have not only provided an integrated view of the disease mechanism but also revealed novel cell biology implicated in neurodegeneration. Furthermore, some of the discoveries have given rise to new ideas for therapeutic development. Here, we review the research progress on cellular pathophysiology of C9ORF72-mediated ALS and FTD and its therapeutic implication. We suggest that the repeat expansion drives pathogenesis through a combination of downstream defects, of which some can be therapeutic targets.
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Affiliation(s)
- Xiaoqiang Tang
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Arturo Toro
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Sahana T G
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Junli Gao
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Jessica Chalk
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | | | - Ke Zhang
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA. .,Neuroscience Graduate Program, Mayo Clinic Graduate School of Biomedical Sciences, Jacksonville, FL, USA.
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81
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Liang C, Shao Q, Zhang W, Yang M, Chang Q, Chen R, Chen JF. Smcr8 deficiency disrupts axonal transport-dependent lysosomal function and promotes axonal swellings and gain of toxicity in C9ALS/FTD mouse models. Hum Mol Genet 2020; 28:3940-3953. [PMID: 31625563 DOI: 10.1093/hmg/ddz230] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2019] [Revised: 08/28/2019] [Accepted: 09/23/2019] [Indexed: 02/06/2023] Open
Abstract
G4C2 repeat expansions in an intron of C9ORF72 cause the most common familial amyotrophic lateral sclerosis and frontotemporal dementia (collectively, C9ALS/FTD). Mechanisms and mediators of C9ALS/FTD pathogenesis remain poorly understood. C9orf72 and Smcr8 form a protein complex. Here, we show that expression of Smcr8, like C9orf72, is reduced in C9ALS/FTD mouse models and patient tissues. Since Smcr8 is highly conserved between human and mouse, we evaluated the effects of Smcr8 downregulation in mice. Smcr8 knockout (KO) mice exhibited motor behavior deficits, which resemble those of C9ALS/FTD mouse models, and displayed axonal swellings in their spinal cords and neuromuscular junctions. These deficits are caused by impaired autophagy-lysosomal functions due to disrupted axonal transport in mutant motor neurons. Consistent with its interaction with C9orf72 and their downregulation in patient tissues, Smcr8 deficiency exacerbated autophagy-lysosomal impairment in C9orf72 KO mice. The disease relevance of Smcr8 downregulation was reflected by exacerbated axonal swellings and gain of toxicity pathology arising from Smcr8 haploinsufficiency in a mouse model of C9ALS/FTD. Thus, our in vivo studies suggested that Smcr8 deficiency impairs axonal transport dependent autophagy-lysosomal function and exacerbates axonal degeneration and gain of toxicity in C9ALS/FTD mouse models.
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Affiliation(s)
- Chen Liang
- Center for Craniofacial Molecular Biology, University of Southern California (USC), Los Angeles, CA 90033, USA.,Department of Cellular Biology, University of Georgia, Athens, GA 30602, USA
| | - Qiang Shao
- Center for Craniofacial Molecular Biology, University of Southern California (USC), Los Angeles, CA 90033, USA
| | - Wei Zhang
- Center for Craniofacial Molecular Biology, University of Southern California (USC), Los Angeles, CA 90033, USA
| | - Mei Yang
- Center for Craniofacial Molecular Biology, University of Southern California (USC), Los Angeles, CA 90033, USA
| | - Qing Chang
- Center for Craniofacial Molecular Biology, University of Southern California (USC), Los Angeles, CA 90033, USA
| | - Rong Chen
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, 100 N. Greene Street, Baltimore, MD 21205, USA
| | - Jian-Fu Chen
- Center for Craniofacial Molecular Biology, University of Southern California (USC), Los Angeles, CA 90033, USA
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82
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Lanznaster D, Veyrat-Durebex C, Vourc’h P, Andres CR, Blasco H, Corcia P. Metabolomics: A Tool to Understand the Impact of Genetic Mutations in Amyotrophic Lateral Sclerosis. Genes (Basel) 2020; 11:genes11050537. [PMID: 32403313 PMCID: PMC7288444 DOI: 10.3390/genes11050537] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 04/27/2020] [Accepted: 04/27/2020] [Indexed: 12/12/2022] Open
Abstract
Metabolomics studies performed in patients with amyotrophic lateral sclerosis (ALS) reveal a set of distinct metabolites that can shed light on the pathological alterations taking place in each individual. Metabolites levels are influenced by disease status, and genetics play an important role both in familial and sporadic ALS cases. Metabolomics analysis helps to unravel the differential impact of the most common ALS-linked genetic mutations (as C9ORF72, SOD1, TARDBP, and FUS) in specific signaling pathways. Further, studies performed in genetic models of ALS reinforce the role of TDP-43 pathology in the vast majority of ALS cases. Studies performed in differentiated cells from ALS-iPSC (induced Pluripotent Stem Cells) reveal alterations in the cell metabolism that are also found in ALS models and ultimately in ALS patients. The development of metabolomics approaches in iPSC derived from ALS patients allow addressing and ultimately understanding the pathological mechanisms taking place in any patient. Lately, the creation of a "patient in a dish" will help to identify patients that may benefit from specific treatments and allow the implementation of personalized medicine.
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Affiliation(s)
- Débora Lanznaster
- UMR 1253, iBrain, University of Tours, Inserm, 37000 Tours, France; (C.V.-D.); (P.V.); (C.R.A.); (H.B.); (P.C.)
- Correspondence:
| | - Charlotte Veyrat-Durebex
- UMR 1253, iBrain, University of Tours, Inserm, 37000 Tours, France; (C.V.-D.); (P.V.); (C.R.A.); (H.B.); (P.C.)
- CHU de Tours, Service de Biochimie et Biologie Moléculaire, 37000 Tours, France
| | - Patrick Vourc’h
- UMR 1253, iBrain, University of Tours, Inserm, 37000 Tours, France; (C.V.-D.); (P.V.); (C.R.A.); (H.B.); (P.C.)
- CHU de Tours, Service de Biochimie et Biologie Moléculaire, 37000 Tours, France
| | - Christian R. Andres
- UMR 1253, iBrain, University of Tours, Inserm, 37000 Tours, France; (C.V.-D.); (P.V.); (C.R.A.); (H.B.); (P.C.)
- CHU de Tours, Service de Biochimie et Biologie Moléculaire, 37000 Tours, France
| | - Hélène Blasco
- UMR 1253, iBrain, University of Tours, Inserm, 37000 Tours, France; (C.V.-D.); (P.V.); (C.R.A.); (H.B.); (P.C.)
- CHU de Tours, Service de Biochimie et Biologie Moléculaire, 37000 Tours, France
| | - Philippe Corcia
- UMR 1253, iBrain, University of Tours, Inserm, 37000 Tours, France; (C.V.-D.); (P.V.); (C.R.A.); (H.B.); (P.C.)
- CHU de Tours, Service de Neurologie, 37000 Tours, France
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83
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Rudich P, Snoznik C, Puleo N, Lamitina T. Measuring RAN Peptide Toxicity in C. elegans. J Vis Exp 2020. [PMID: 32420986 DOI: 10.3791/61024] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
C. elegans is commonly used to model age-related neurodegenerative diseases caused by repeat expansion mutations, such as Amyotrophic Lateral Sclerosis (ALS) and Huntington's disease. Recently, repeat expansion-containing RNA was shown to be the substrate for a novel type of protein translation called repeat-associated non-AUG-dependent (RAN) translation. Unlike canonical translation, RAN translation does not require a start codon and only occurs when repeats exceed a threshold length. Because there is no start codon to determine the reading frame, RAN translation occurs in all reading frames from both sense and antisense RNA templates that contain a repeat expansion sequence. Therefore, RAN translation expands the number of possible disease-associated toxic peptides from one to six. Thus far, RAN translation has been documented in eight different repeat expansion-based neurodegenerative and neuromuscular diseases. In each case, deciphering which RAN products are toxic, as well as their mechanisms of toxicity, is a critical step towards understanding how these peptides contribute to disease pathophysiology. In this paper, we present strategies to measure the toxicity of RAN peptides in the model system C. elegans. First, we describe procedures for measuring RAN peptide toxicity on the growth and motility of developing C. elegans. Second, we detail an assay for measuring postdevelopmental, age-dependent effects of RAN peptides on motility. Finally, we describe a neurotoxicity assay for evaluating the effects of RAN peptides on neuron morphology. These assays provide a broad assessment of RAN peptide toxicity and may be useful for performing large-scale genetic or small molecule screens to identify disease mechanisms or therapies.
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Affiliation(s)
- Paige Rudich
- Graduate Program in Cell Biology and Molecular Physiology, University of Pittsburgh
| | - Carley Snoznik
- Department of Pediatrics, University of Pittsburgh School of Medicine
| | - Noah Puleo
- Department of Pediatrics, University of Pittsburgh School of Medicine
| | - Todd Lamitina
- Graduate Program in Cell Biology and Molecular Physiology, University of Pittsburgh; Department of Pediatrics, University of Pittsburgh School of Medicine;
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84
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Suzuki N, Akiyama T, Warita H, Aoki M. Omics Approach to Axonal Dysfunction of Motor Neurons in Amyotrophic Lateral Sclerosis (ALS). Front Neurosci 2020; 14:194. [PMID: 32269505 PMCID: PMC7109447 DOI: 10.3389/fnins.2020.00194] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 02/24/2020] [Indexed: 12/12/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is an intractable adult-onset neurodegenerative disease that leads to the loss of upper and lower motor neurons (MNs). The long axons of MNs become damaged during the early stages of ALS. Genetic and pathological analyses of ALS patients have revealed dysfunction in the MN axon homeostasis. However, the molecular pathomechanism for the degeneration of axons in ALS has not been fully elucidated. This review provides an overview of the proposed axonal pathomechanisms in ALS, including those involving the neuronal cytoskeleton, cargo transport within axons, axonal energy supply, clearance of junk protein, neuromuscular junctions (NMJs), and aberrant axonal branching. To improve understanding of the global changes in axons, the review summarizes omics analyses of the axonal compartments of neurons in vitro and in vivo, including a motor nerve organoid approach that utilizes microfluidic devices developed by this research group. The review also discusses the relevance of intra-axonal transcription factors frequently identified in these omics analyses. Local axonal translation and the relationship among these pathomechanisms should be pursued further. The development of novel strategies to analyze axon fractions provides a new approach to establishing a detailed understanding of resilience of long MN and MN pathology in ALS.
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Affiliation(s)
- Naoki Suzuki
- Department of Neurology, Tohoku University School of Medicine, Sendai, Japan.,Department of Neurology, Shodo-kai Southern Tohoku General Hospital, Miyagi, Japan
| | - Tetsuya Akiyama
- Department of Neurology, Tohoku University School of Medicine, Sendai, Japan
| | - Hitoshi Warita
- Department of Neurology, Tohoku University School of Medicine, Sendai, Japan
| | - Masashi Aoki
- Department of Neurology, Tohoku University School of Medicine, Sendai, Japan
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85
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Chen KW, Chen JA. Functional Roles of Long Non-coding RNAs in Motor Neuron Development and Disease. J Biomed Sci 2020; 27:38. [PMID: 32093746 PMCID: PMC7041250 DOI: 10.1186/s12929-020-00628-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 02/12/2020] [Indexed: 12/14/2022] Open
Abstract
Long non-coding RNAs (lncRNAs) have gained increasing attention as they exhibit highly tissue- and cell-type specific expression patterns. LncRNAs are highly expressed in the central nervous system and their roles in the brain have been studied intensively in recent years, but their roles in the spinal motor neurons (MNs) are largely unexplored. Spinal MN development is controlled by precise expression of a gene regulatory network mediated spatiotemporally by transcription factors, representing an elegant paradigm for deciphering the roles of lncRNAs during development. Moreover, many MN-related neurodegenerative diseases, such as amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA), are associated with RNA metabolism, yet the link between MN-related diseases and lncRNAs remains obscure. In this review, we summarize lncRNAs known to be involved in MN development and disease, and discuss their potential future therapeutic applications.
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Affiliation(s)
- Kuan-Wei Chen
- Institute of Molecular Biology, Academia Sinica, Taipei, 11529, Taiwan.
| | - Jun-An Chen
- Institute of Molecular Biology, Academia Sinica, Taipei, 11529, Taiwan.
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86
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Jury N, Abarzua S, Diaz I, Guerra MV, Ampuero E, Cubillos P, Martinez P, Herrera-Soto A, Arredondo C, Rojas F, Manterola M, Rojas A, Montecino M, Varela-Nallar L, van Zundert B. Widespread loss of the silencing epigenetic mark H3K9me3 in astrocytes and neurons along with hippocampal-dependent cognitive impairment in C9orf72 BAC transgenic mice. Clin Epigenetics 2020; 12:32. [PMID: 32070418 PMCID: PMC7029485 DOI: 10.1186/s13148-020-0816-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 01/23/2020] [Indexed: 12/13/2022] Open
Abstract
Background Hexanucleotide repeat expansions of the G4C2 motif in a non-coding region of the C9ORF72 gene are the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Tissues from C9ALS/FTD patients and from mouse models of ALS show RNA foci, dipeptide-repeat proteins, and notably, widespread alterations in the transcriptome. Epigenetic processes regulate gene expression without changing DNA sequences and therefore could account for the altered transcriptome profiles in C9ALS/FTD; here, we explore whether the critical repressive marks H3K9me2 and H3K9me3 are altered in a recently developed C9ALS/FTD BAC mouse model (C9BAC). Results Chromocenters that constitute pericentric constitutive heterochromatin were visualized as DAPI- or Nucblue-dense foci in nuclei. Cultured C9BAC astrocytes exhibited a reduced staining signal for H3K9me3 (but not for H3K9me2) at chromocenters that was accompanied by a marked decline in the global nuclear level of this mark. Similar depletion of H3K9me3 at chromocenters was detected in astrocytes and neurons of the spinal cord, motor cortex, and hippocampus of C9BAC mice. The alterations of H3K9me3 in the hippocampus of C9BAC mice led us to identify previously undetected neuronal loss in CA1, CA3, and dentate gyrus, as well as hippocampal-dependent cognitive deficits. Conclusions Our data indicate that a loss of the repressive mark H3K9me3 in astrocytes and neurons in the central nervous system of C9BAC mice represents a signature during neurodegeneration and memory deficit of C9ALS/FTD.
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Affiliation(s)
- Nur Jury
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile.,CARE Biomedical Research Center, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Sebastian Abarzua
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile.,CARE Biomedical Research Center, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile.,FONDAP Center for Genome Regulation, Santiago, Chile
| | - Ivan Diaz
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile.,CARE Biomedical Research Center, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Miguel V Guerra
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile
| | - Estibaliz Ampuero
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile.,CARE Biomedical Research Center, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile.,Current address: Faculty of Health Sciences, Universidad Autónoma de Chile, Santiago, Chile
| | - Paula Cubillos
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile.,CARE Biomedical Research Center, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Pablo Martinez
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile.,CARE Biomedical Research Center, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Andrea Herrera-Soto
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile
| | - Cristian Arredondo
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile.,CARE Biomedical Research Center, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Fabiola Rojas
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile.,CARE Biomedical Research Center, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Marcia Manterola
- Program of Human Genetics, ICBM, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Adriana Rojas
- Instituto de Genética Humana, Pontificia Universidad Javeriana, Bogotá, Colombia
| | - Martín Montecino
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile.,FONDAP Center for Genome Regulation, Santiago, Chile
| | - Lorena Varela-Nallar
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile.
| | - Brigitte van Zundert
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile. .,CARE Biomedical Research Center, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile.
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87
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Abramzon YA, Fratta P, Traynor BJ, Chia R. The Overlapping Genetics of Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Front Neurosci 2020; 14:42. [PMID: 32116499 PMCID: PMC7012787 DOI: 10.3389/fnins.2020.00042] [Citation(s) in RCA: 134] [Impact Index Per Article: 33.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 01/13/2020] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are two diseases that form a broad neurodegenerative continuum. Considerable effort has been made to unravel the genetics of these disorders, and, based on this work, it is now clear that ALS and FTD have a significant genetic overlap. TARDBP, SQSTM1, VCP, FUS, TBK1, CHCHD10, and most importantly C9orf72, are the critical genetic players in these neurological disorders. Discoveries of these genes have implicated autophagy, RNA regulation, and vesicle and inclusion formation as the central pathways involved in neurodegeneration. Here we provide a summary of the significant genes identified in these two intrinsically linked neurodegenerative diseases and highlight the genetic and pathological overlaps.
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Affiliation(s)
- Yevgeniya A. Abramzon
- Neuromuscular Diseases Research Section, Laboratory of Neurogenetics, National Institute on Aging, NIH, Bethesda, MD, United States
- Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London, London, United Kingdom
| | - Pietro Fratta
- Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London, London, United Kingdom
| | - Bryan J. Traynor
- Neuromuscular Diseases Research Section, Laboratory of Neurogenetics, National Institute on Aging, NIH, Bethesda, MD, United States
- Department of Neurology, Brain Science Institute, Johns Hopkins University, Baltimore, MD, United States
| | - Ruth Chia
- Neuromuscular Diseases Research Section, Laboratory of Neurogenetics, National Institute on Aging, NIH, Bethesda, MD, United States
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88
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Filipi T, Hermanova Z, Tureckova J, Vanatko O, Anderova M. Glial Cells-The Strategic Targets in Amyotrophic Lateral Sclerosis Treatment. J Clin Med 2020; 9:E261. [PMID: 31963681 PMCID: PMC7020059 DOI: 10.3390/jcm9010261] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 01/13/2020] [Accepted: 01/16/2020] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurological disease, which is characterized by the degeneration of motor neurons in the motor cortex and the spinal cord and subsequently by muscle atrophy. To date, numerous gene mutations have been linked to both sporadic and familial ALS, but the effort of many experimental groups to develop a suitable therapy has not, as of yet, proven successful. The original focus was on the degenerating motor neurons, when researchers tried to understand the pathological mechanisms that cause their slow death. However, it was soon discovered that ALS is a complicated and diverse pathology, where not only neurons, but also other cell types, play a crucial role via the so-called non-cell autonomous effect, which strongly deteriorates neuronal conditions. Subsequently, variable glia-based in vitro and in vivo models of ALS were established and used for brand-new experimental and clinical approaches. Such a shift towards glia soon bore its fruit in the form of several clinical studies, which more or less successfully tried to ward the unfavourable prognosis of ALS progression off. In this review, we aimed to summarize current knowledge regarding the involvement of each glial cell type in the progression of ALS, currently available treatments, and to provide an overview of diverse clinical trials covering pharmacological approaches, gene, and cell therapies.
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Affiliation(s)
- Tereza Filipi
- Department of Cellular Neurophysiology, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, 14200 Prague, Czech Republic; (T.F.); (Z.H.); (J.T.); (O.V.)
- 2nd Faculty of Medicine, Charles University, 15006 Prague, Czech Republic
| | - Zuzana Hermanova
- Department of Cellular Neurophysiology, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, 14200 Prague, Czech Republic; (T.F.); (Z.H.); (J.T.); (O.V.)
- 2nd Faculty of Medicine, Charles University, 15006 Prague, Czech Republic
| | - Jana Tureckova
- Department of Cellular Neurophysiology, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, 14200 Prague, Czech Republic; (T.F.); (Z.H.); (J.T.); (O.V.)
| | - Ondrej Vanatko
- Department of Cellular Neurophysiology, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, 14200 Prague, Czech Republic; (T.F.); (Z.H.); (J.T.); (O.V.)
| | - Miroslava Anderova
- Department of Cellular Neurophysiology, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, 14200 Prague, Czech Republic; (T.F.); (Z.H.); (J.T.); (O.V.)
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89
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Boivin M, Pfister V, Gaucherot A, Ruffenach F, Negroni L, Sellier C, Charlet-Berguerand N. Reduced autophagy upon C9ORF72 loss synergizes with dipeptide repeat protein toxicity in G4C2 repeat expansion disorders. EMBO J 2020; 39:e100574. [PMID: 31930538 PMCID: PMC7024836 DOI: 10.15252/embj.2018100574] [Citation(s) in RCA: 81] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 11/28/2019] [Accepted: 12/03/2019] [Indexed: 12/12/2022] Open
Abstract
Expansion of G4C2 repeats within the C9ORF72 gene is the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Such repeats lead to decreased expression of the autophagy regulator C9ORF72 protein. Furthermore, sense and antisense repeats are translated into toxic dipeptide repeat (DPR) proteins. It is unclear how these repeats are translated, and in which way their translation and the reduced expression of C9ORF72 modulate repeat toxicity. Here, we found that sense and antisense repeats are translated upon initiation at canonical AUG or near‐cognate start codons, resulting in polyGA‐, polyPG‐, and to a lesser degree polyGR‐DPR proteins. However, accumulation of these proteins is prevented by autophagy. Importantly, reduced C9ORF72 levels lead to suboptimal autophagy, thereby impairing clearance of DPR proteins and causing their toxic accumulation, ultimately resulting in neuronal cell death. Of clinical importance, pharmacological compounds activating autophagy can prevent neuronal cell death caused by DPR proteins accumulation. These results suggest the existence of a double‐hit pathogenic mechanism in ALS/FTD, whereby reduced expression of C9ORF72 synergizes with DPR protein accumulation and toxicity.
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Affiliation(s)
- Manon Boivin
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France.,Université de Strasbourg, Illkirch, France.,Centre National de la Recherche Scientifique, UMR7104, Illkirch, France.,Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France
| | - Véronique Pfister
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France.,Université de Strasbourg, Illkirch, France.,Centre National de la Recherche Scientifique, UMR7104, Illkirch, France.,Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France
| | - Angeline Gaucherot
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France.,Université de Strasbourg, Illkirch, France.,Centre National de la Recherche Scientifique, UMR7104, Illkirch, France.,Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France
| | - Frank Ruffenach
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France.,Université de Strasbourg, Illkirch, France.,Centre National de la Recherche Scientifique, UMR7104, Illkirch, France.,Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France
| | - Luc Negroni
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France.,Université de Strasbourg, Illkirch, France.,Centre National de la Recherche Scientifique, UMR7104, Illkirch, France.,Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France
| | - Chantal Sellier
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France.,Université de Strasbourg, Illkirch, France.,Centre National de la Recherche Scientifique, UMR7104, Illkirch, France.,Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France
| | - Nicolas Charlet-Berguerand
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France.,Université de Strasbourg, Illkirch, France.,Centre National de la Recherche Scientifique, UMR7104, Illkirch, France.,Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France
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90
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Liu EY, Russ J, Lee EB. Neuronal Transcriptome from C9orf72 Repeat Expanded Human Tissue is Associated with Loss of C9orf72 Function. FREE NEUROPATHOLOGY 2020; 1:23. [PMID: 32905541 PMCID: PMC7470232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A hexanucleotide G4C2 repeat expansion in C9orf72 is the most common genetic cause of familial and sporadic cases of amyotrophic lateral sclerosis (ALS) and frontotemporal degeneration (FTD). The mutation is associated with a reduction of C9orf72 protein and accumulation of toxic RNA and dipeptide repeat aggregates. The accumulation of toxic RNA has been proposed to sequester RNA binding proteins thereby altering RNA processing, consistent with previous transcriptome studies that have shown that the C9orf72 repeat expansion is linked to abundant splicing alterations and transcriptome changes. Here, we used a subcellular fractionation method and FACS to enrich for neuronal nuclei from C9orf72 repeat expanded post-mortem human ALS/FTD brains, and to remove neuronal nuclei with TDP-43 pathology which are observed in nearly all symptomatic C9orf72 repeat expanded cases. We show that the C9orf72 expansion is associated with relatively mild gene expression changes. Dysregulated genes were enriched for vesicle transport pathways, which is consistent with the known functions of C9orf72 protein. Further analysis suggests that the C9orf72 transcriptome is not driven by toxic RNA but is rather shaped by the depletion of pathologic TDP-43 nuclei and the loss of C9orf72 expression. These findings argue against RNA binding protein sequestration in neurons as a major contributor to C9orf72 mediated toxicity.
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Affiliation(s)
- Elaine Y. Liu
- Translational Neuropathology Research Laboratory, University of Pennsylvania, Philadelphia, PA, USA
| | - Jenny Russ
- Translational Neuropathology Research Laboratory, University of Pennsylvania, Philadelphia, PA, USA
| | - Edward B. Lee
- Translational Neuropathology Research Laboratory, University of Pennsylvania, Philadelphia, PA, USA
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91
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Congenic expression of poly-GA but not poly-PR in mice triggers selective neuron loss and interferon responses found in C9orf72 ALS. Acta Neuropathol 2020; 140:121-142. [PMID: 32562018 PMCID: PMC7360660 DOI: 10.1007/s00401-020-02176-0] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 06/04/2020] [Accepted: 06/04/2020] [Indexed: 12/13/2022]
Abstract
Expansion of a (G4C2)n repeat in C9orf72 causes amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), but the link of the five repeat-encoded dipeptide repeat (DPR) proteins to neuroinflammation, TDP-43 pathology, and neurodegeneration is unclear. Poly-PR is most toxic in vitro, but poly-GA is far more abundant in patients. To directly compare these in vivo, we created congenic poly-GA and poly-PR mice. 40% of poly-PR mice were affected with ataxia and seizures, requiring euthanasia by 6 weeks of age. The remaining poly-PR mice were asymptomatic at 14 months of age, likely due to an 80% reduction of the transgene mRNA in this subgroup. In contrast, all poly-GA mice showed selective neuron loss, inflammation, as well as muscle denervation and wasting requiring euthanasia before 7 weeks of age. In-depth analysis of peripheral organs and blood samples suggests that peripheral organ failure does not drive these phenotypes. Although transgene mRNA levels were similar between poly-GA and affected poly-PR mice, poly-GA aggregated far more abundantly than poly-PR in the CNS and was also found in skeletal muscle. In addition, TDP-43 and other disease-linked RNA-binding proteins co-aggregated in rare nuclear inclusions in the hippocampus and frontal cortex only in poly-GA mice. Transcriptome analysis revealed activation of an interferon-responsive pro-inflammatory microglial signature in end-stage poly-GA but not poly-PR mice. This signature was also found in all ALS patients and enriched in C9orf72 cases. In summary, our rigorous comparison of poly-GA and poly-PR toxicity in vivo indicates that poly-GA, but not poly-PR at the same mRNA expression level, promotes interferon responses in C9orf72 disease and contributes to TDP-43 abnormalities and neuron loss selectively in disease-relevant regions.
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92
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Nguyen L, Montrasio F, Pattamatta A, Tusi SK, Bardhi O, Meyer KD, Hayes L, Nakamura K, Banez-Coronel M, Coyne A, Guo S, Laboissonniere LA, Gu Y, Narayanan S, Smith B, Nitsch RM, Kankel MW, Rushe M, Rothstein J, Zu T, Grimm J, Ranum LPW. Antibody Therapy Targeting RAN Proteins Rescues C9 ALS/FTD Phenotypes in C9orf72 Mouse Model. Neuron 2019; 105:645-662.e11. [PMID: 31831332 DOI: 10.1016/j.neuron.2019.11.007] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 10/10/2019] [Accepted: 11/05/2019] [Indexed: 10/25/2022]
Abstract
The intronic C9orf72 G4C2 expansion, the most common genetic cause of ALS and FTD, produces sense- and antisense-expansion RNAs and six dipeptide repeat-associated, non-ATG (RAN) proteins, but their roles in disease are unclear. We generated high-affinity human antibodies targeting GA or GP RAN proteins. These antibodies cross the blood-brain barrier and co-localize with intracellular RAN aggregates in C9-ALS/FTD BAC mice. In cells, α-GA1 interacts with TRIM21, and α-GA1 treatment reduced GA levels, increased GA turnover, and decreased RAN toxicity and co-aggregation of proteasome and autophagy proteins to GA aggregates. In C9-BAC mice, α-GA1 reduced GA as well as GP and GR proteins, improved behavioral deficits, decreased neuroinflammation and neurodegeneration, and increased survival. Glycosylation of the Fc region of α-GA1 is important for cell entry and efficacy. These data demonstrate that RAN proteins drive C9-ALS/FTD in C9-BAC transgenic mice and establish a novel therapeutic approach for C9orf72 ALS/FTD and other RAN-protein diseases.
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Affiliation(s)
- Lien Nguyen
- Center for NeuroGenetics, Department of Molecular Genetics and Microbiology, Genetics Institute, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32610, USA
| | | | - Amrutha Pattamatta
- Center for NeuroGenetics, Department of Molecular Genetics and Microbiology, Genetics Institute, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32610, USA
| | - Solaleh Khoramian Tusi
- Center for NeuroGenetics, Department of Molecular Genetics and Microbiology, Genetics Institute, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32610, USA
| | - Olgert Bardhi
- Center for NeuroGenetics, Department of Molecular Genetics and Microbiology, Genetics Institute, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32610, USA
| | - Kevin D Meyer
- Neurimmune AG, 8952 Schlieren, Switzerland; Institute for Regenerative Medicine-IREM, University of Zurich, 8952 Schlieren, Switzerland
| | - Lindsey Hayes
- Department of Neurology, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Katsuya Nakamura
- Center for NeuroGenetics, Department of Molecular Genetics and Microbiology, Genetics Institute, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32610, USA
| | - Monica Banez-Coronel
- Center for NeuroGenetics, Department of Molecular Genetics and Microbiology, Genetics Institute, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32610, USA
| | - Alyssa Coyne
- Department of Neurology, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Shu Guo
- Center for NeuroGenetics, Department of Molecular Genetics and Microbiology, Genetics Institute, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32610, USA
| | - Lauren A Laboissonniere
- Center for NeuroGenetics, Department of Molecular Genetics and Microbiology, Genetics Institute, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32610, USA
| | - Yuanzheng Gu
- Neuromuscular and Movement Disorders, Biogen, Cambridge, MA 02142, USA
| | | | - Benjamin Smith
- Neuromuscular and Movement Disorders, Biogen, Cambridge, MA 02142, USA
| | - Roger M Nitsch
- Neurimmune AG, 8952 Schlieren, Switzerland; Institute for Regenerative Medicine-IREM, University of Zurich, 8952 Schlieren, Switzerland
| | - Mark W Kankel
- Neuromuscular and Movement Disorders, Biogen, Cambridge, MA 02142, USA
| | - Mia Rushe
- Neuromuscular and Movement Disorders, Biogen, Cambridge, MA 02142, USA
| | - Jeffrey Rothstein
- Department of Neurology, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Tao Zu
- Center for NeuroGenetics, Department of Molecular Genetics and Microbiology, Genetics Institute, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32610, USA
| | - Jan Grimm
- Neurimmune AG, 8952 Schlieren, Switzerland
| | - Laura P W Ranum
- Center for NeuroGenetics, Department of Molecular Genetics and Microbiology, Genetics Institute, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32610, USA.
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93
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Mejzini R, Flynn LL, Pitout IL, Fletcher S, Wilton SD, Akkari PA. ALS Genetics, Mechanisms, and Therapeutics: Where Are We Now? Front Neurosci 2019; 13:1310. [PMID: 31866818 PMCID: PMC6909825 DOI: 10.3389/fnins.2019.01310] [Citation(s) in RCA: 435] [Impact Index Per Article: 87.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Accepted: 11/22/2019] [Indexed: 12/11/2022] Open
Abstract
The scientific landscape surrounding amyotrophic lateral sclerosis (ALS) continues to shift as the number of genes associated with the disease risk and pathogenesis, and the cellular processes involved, continues to grow. Despite decades of intense research and over 50 potentially causative or disease-modifying genes identified, etiology remains unexplained and treatment options remain limited for the majority of ALS patients. Various factors have contributed to the slow progress in understanding and developing therapeutics for this disease. Here, we review the genetic basis of ALS, highlighting factors that have contributed to the elusiveness of genetic heritability. The most commonly mutated ALS-linked genes are reviewed with an emphasis on disease-causing mechanisms. The cellular processes involved in ALS pathogenesis are discussed, with evidence implicating their involvement in ALS summarized. Past and present therapeutic strategies and the benefits and limitations of the model systems available to ALS researchers are discussed with future directions for research that may lead to effective treatment strategies outlined.
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Affiliation(s)
- Rita Mejzini
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth, WA, Australia
- The Perron Institute for Neurological and Translational Science, Perth, WA, Australia
| | - Loren L. Flynn
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth, WA, Australia
- The Perron Institute for Neurological and Translational Science, Perth, WA, Australia
- Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Perth, WA, Australia
| | - Ianthe L. Pitout
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth, WA, Australia
- The Perron Institute for Neurological and Translational Science, Perth, WA, Australia
- Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Perth, WA, Australia
| | - Sue Fletcher
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth, WA, Australia
- The Perron Institute for Neurological and Translational Science, Perth, WA, Australia
- Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Perth, WA, Australia
| | - Steve D. Wilton
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth, WA, Australia
- The Perron Institute for Neurological and Translational Science, Perth, WA, Australia
- Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Perth, WA, Australia
| | - P. Anthony Akkari
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth, WA, Australia
- The Perron Institute for Neurological and Translational Science, Perth, WA, Australia
- Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Perth, WA, Australia
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94
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Hawrot J, Imhof S, Wainger BJ. Modeling cell-autonomous motor neuron phenotypes in ALS using iPSCs. Neurobiol Dis 2019; 134:104680. [PMID: 31759135 DOI: 10.1016/j.nbd.2019.104680] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 10/29/2019] [Accepted: 11/15/2019] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is an aggressive and uniformly fatal degenerative disease of the motor nervous system. In order to understand underlying disease mechanisms, researchers leverage a host of in vivo and in vitro models, including yeast, worms, flies, zebrafish, mice, and more recently, human induced pluripotent stem cells (iPSCs) derived from ALS patients. While mouse models have been the main workhorse of preclinical ALS research, the development of iPSCs provides a new opportunity to explore molecular phenotypes of ALS within human cells. Importantly, this technology enables modeling of both familial and sporadic ALS in the relevant human genetic backgrounds, as well as a personalized or targeted approach to therapy development. Harnessing these powerful tools requires addressing numerous challenges, including different variance components associated with iPSCs and motor neurons as well as concomitant limits of reductionist approaches. In order to overcome these obstacles, optimization of protocols and assays, confirmation of phenotype robustness at scale, and validation of findings in human tissue and genetics will cement the role for iPSC models as a valuable complement to animal models in ALS and more broadly among neurodegenerative diseases.
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Affiliation(s)
- James Hawrot
- Departments of Neurology and Anesthesia, Critical Care & Pain Medicine, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Sophie Imhof
- Departments of Neurology and Anesthesia, Critical Care & Pain Medicine, Massachusetts General Hospital, Boston, MA 02114, USA; University of Amsterdam, Amsterdam, The Netherlands
| | - Brian J Wainger
- Departments of Neurology and Anesthesia, Critical Care & Pain Medicine, Massachusetts General Hospital, Boston, MA 02114, USA; Harvard Stem Cell Institute, Cambridge, MA 02138, USA; Broad Institute of Harvard University and MIT, Cambridge, MA 02142, USA.
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95
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CRISPR/Cas9 does not facilitate stable expression of long C9orf72 dipeptides in mice. Neurobiol Aging 2019; 84:235.e1-235.e8. [PMID: 31676125 DOI: 10.1016/j.neurobiolaging.2019.09.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 09/17/2019] [Accepted: 09/19/2019] [Indexed: 11/24/2022]
Abstract
A C9orf72 repeat expansion is the most common cause of both frontotemporal dementia and motor neuron disease. The expansion is translated to produce dipeptide repeat proteins (DPRs), which are toxic in vivo and in vitro. However, the mechanisms underlying DPR toxicity remain unclear. Mouse models which express DPRs at repeat lengths found in human disease are urgently required to investigate this. We aimed to generate transgenic mice expressing DPRs at repeat lengths of >1000 using alternative codon sequences, to reduce the repetitive nature of the insert. We found that although these inserts did integrate into the mouse genome, the alternative codon sequences did not protect from instability between generations. Our findings suggest that stable integration of long DPR sequences may not be possible. Administration of viral vectors after birth may be a more effective delivery method for long repeats.
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96
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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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97
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Cappella M, Ciotti C, Cohen-Tannoudji M, Biferi MG. Gene Therapy for ALS-A Perspective. Int J Mol Sci 2019; 20:E4388. [PMID: 31500113 PMCID: PMC6771059 DOI: 10.3390/ijms20184388] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 08/30/2019] [Accepted: 09/03/2019] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal motor neuron disease (MND) with no cure. Recent advances in gene therapy open a new perspective to treat this disorder-particularly for the characterized genetic forms. Gene therapy approaches, involving the delivery of antisense oligonucleotides into the central nervous system (CNS) are being tested in clinical trials for patients with mutations in SOD1 or C9orf72 genes. Viral vectors can be used to deliver therapeutic sequences to stably transduce motor neurons in the CNS. Vectors derived from adeno-associated virus (AAV), can efficiently target genes and have been tested in several pre-clinical settings with promising outcomes. Recently, the Food and Drug Administration (FDA) approved Zolgensma, an AAV-mediated treatment for another MND-the infant form of spinal muscular atrophy. Given the accelerated progress in gene therapy, it is potentially a promising avenue to develop an efficient and safe cure for ALS.
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Affiliation(s)
- Marisa Cappella
- Sorbonne Université, Inserm UMRS 974, Centre of Research in Myology (CRM), Institut de Myologie, GH Pitié Salpêtrière, 75013 Paris, France
| | - Chiara Ciotti
- Sorbonne Université, Inserm UMRS 974, Centre of Research in Myology (CRM), Institut de Myologie, GH Pitié Salpêtrière, 75013 Paris, France
| | - Mathilde Cohen-Tannoudji
- Sorbonne Université, Inserm UMRS 974, Centre of Research in Myology (CRM), Institut de Myologie, GH Pitié Salpêtrière, 75013 Paris, France
| | - Maria Grazia Biferi
- Sorbonne Université, Inserm UMRS 974, Centre of Research in Myology (CRM), Institut de Myologie, GH Pitié Salpêtrière, 75013 Paris, France.
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98
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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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99
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Solomon DA, Stepto A, Au WH, Adachi Y, Diaper DC, Hall R, Rekhi A, Boudi A, Tziortzouda P, Lee YB, Smith B, Bridi JC, Spinelli G, Dearlove J, Humphrey DM, Gallo JM, Troakes C, Fanto M, Soller M, Rogelj B, Parsons RB, Shaw CE, Hortobágyi T, Hirth F. A feedback loop between dipeptide-repeat protein, TDP-43 and karyopherin-α mediates C9orf72-related neurodegeneration. Brain 2019; 141:2908-2924. [PMID: 30239641 PMCID: PMC6158706 DOI: 10.1093/brain/awy241] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 08/02/2018] [Indexed: 12/13/2022] Open
Abstract
Accumulation and aggregation of TDP-43 is a major pathological hallmark of amyotrophic lateral sclerosis and frontotemporal dementia. TDP-43 inclusions also characterize patients with GGGGCC (G4C2) hexanucleotide repeat expansion in C9orf72 that causes the most common genetic form of amyotrophic lateral sclerosis and frontotemporal dementia (C9ALS/FTD). Functional studies in cell and animal models have identified pathogenic mechanisms including repeat-induced RNA toxicity and accumulation of G4C2-derived dipeptide-repeat proteins. The role of TDP-43 dysfunction in C9ALS/FTD, however, remains elusive. We found G4C2-derived dipeptide-repeat protein but not G4C2-RNA accumulation caused TDP-43 proteinopathy that triggered onset and progression of disease in Drosophila models of C9ALS/FTD. Timing and extent of TDP-43 dysfunction was dependent on levels and identity of dipeptide-repeat proteins produced, with poly-GR causing early and poly-GA/poly-GP causing late onset of disease. Accumulating cytosolic, but not insoluble aggregated TDP-43 caused karyopherin-α2/4 (KPNA2/4) pathology, increased levels of dipeptide-repeat proteins and enhanced G4C2-related toxicity. Comparable KPNA4 pathology was observed in both sporadic frontotemporal dementia and C9ALS/FTD patient brains characterized by its nuclear depletion and cytosolic accumulation, irrespective of TDP-43 or dipeptide-repeat protein aggregates. These findings identify a vicious feedback cycle for dipeptide-repeat protein-mediated TDP-43 and subsequent KPNA pathology, which becomes self-sufficient of the initiating trigger and causes C9-related neurodegeneration.
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Affiliation(s)
- Daniel A Solomon
- King's College London, Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Alan Stepto
- King's College London, Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Wing Hei Au
- King's College London, Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Yoshitsugu Adachi
- King's College London, Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Danielle C Diaper
- King's College London, Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Rachel Hall
- King's College London, Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Anjeet Rekhi
- King's College London, Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Adel Boudi
- King's College London, Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Paraskevi Tziortzouda
- King's College London, Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Youn-Bok Lee
- King's College London, Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Bradley Smith
- King's College London, Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Jessika C Bridi
- King's College London, Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Greta Spinelli
- King's College London, Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Jonah Dearlove
- King's College London, Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Dickon M Humphrey
- King's College London, Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Jean-Marc Gallo
- King's College London, Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Claire Troakes
- King's College London, Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Manolis Fanto
- King's College London, Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Matthias Soller
- School of Biosciences, College of Life and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, UK
| | - Boris Rogelj
- Jozef Stefan Institute, Department of Biotechnology and Biomedical Research Institute BRIS and University of Ljubljana, Faculty of Chemistry and Chemical Technology, Ljubljana, Slovenia
| | - Richard B Parsons
- King's College London, School of Cancer Studies and Pharmaceutical Sciences, London, UK
| | - Christopher E Shaw
- King's College London, Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Tibor Hortobágyi
- MTA-DE Cerebrovascular and Neurodegenerative Research Group, Departments of Neurology and Neuropathology, University of Debrecen, Debrecen, Hungary.,King's College London, Department of Old Age Psychiatry, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Frank Hirth
- King's College London, Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, London, UK
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100
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Hao Z, Liu L, Tao Z, Wang R, Ren H, Sun H, Lin Z, Zhang Z, Mu C, Zhou J, Wang G. Motor dysfunction and neurodegeneration in a C9orf72 mouse line expressing poly-PR. Nat Commun 2019; 10:2906. [PMID: 31266945 PMCID: PMC6606620 DOI: 10.1038/s41467-019-10956-w] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 06/12/2019] [Indexed: 12/13/2022] Open
Abstract
A GGGGCC hexanucleotide repeat expansion in intron 1 of chromosome 9 open reading frame 72 (C9ORF72) gene is the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia. Repeat-associated non-ATG translation of dipeptide repeat proteins (DPRs) contributes to the neuropathological features of c9FTD/ALS. Among the five DPRs, arginine-rich poly-PR are reported to be the most toxic. Here, we generate a transgenic mouse line that expresses poly-PR (GFP-PR28) specifically in neurons. GFP-PR28 homozygous mice show decreased survival time, while the heterozygous mice show motor imbalance, decreased brain weight, loss of Purkinje cells and lower motor neurons, and inflammation in the cerebellum and spinal cord. Transcriptional analysis shows that in the cerebellum, GFP-PR28 heterozygous mice show differential expression of genes related to synaptic transmission. Our findings show that GFP-PR28 transgenic mice partly model neuropathological features of c9FTD/ALS, and show a role for poly-PR in neurodegeneration.
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Affiliation(s)
- Zongbing Hao
- Laboratory of Molecular Neuropathology, Jiangsu Key Laboratory of Neuropsychiatric Diseases & Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Liu Liu
- Laboratory of Molecular Neuropathology, Jiangsu Key Laboratory of Neuropsychiatric Diseases & Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Zhouteng Tao
- Center for Drug Safety Evaluation and Research, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China
| | - Rui Wang
- Laboratory of Molecular Neuropathology, Jiangsu Key Laboratory of Neuropsychiatric Diseases & Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Haigang Ren
- Laboratory of Molecular Neuropathology, Jiangsu Key Laboratory of Neuropsychiatric Diseases & Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Hongyang Sun
- Laboratory of Molecular Neuropathology, Jiangsu Key Laboratory of Neuropsychiatric Diseases & Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Zixuan Lin
- Laboratory of Molecular Neuropathology, Jiangsu Key Laboratory of Neuropsychiatric Diseases & Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Zhixiong Zhang
- Laboratory of Molecular Neuropathology, Jiangsu Key Laboratory of Neuropsychiatric Diseases & Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Chenchen Mu
- Laboratory of Molecular Neuropathology, Jiangsu Key Laboratory of Neuropsychiatric Diseases & Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Jiawei Zhou
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Chinese Academy of Sciences Center for Excellence in Brain Science, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Guanghui Wang
- Laboratory of Molecular Neuropathology, Jiangsu Key Laboratory of Neuropsychiatric Diseases & Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, 215123, China.
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