1
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An Z, Jiang A, Chen J. Toward understanding the role of genomic repeat elements in neurodegenerative diseases. Neural Regen Res 2025; 20:646-659. [PMID: 38886931 DOI: 10.4103/nrr.nrr-d-23-01568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Accepted: 03/02/2024] [Indexed: 06/20/2024] Open
Abstract
Neurodegenerative diseases cause great medical and economic burdens for both patients and society; however, the complex molecular mechanisms thereof are not yet well understood. With the development of high-coverage sequencing technology, researchers have started to notice that genomic repeat regions, previously neglected in search of disease culprits, are active contributors to multiple neurodegenerative diseases. In this review, we describe the association between repeat element variants and multiple degenerative diseases through genome-wide association studies and targeted sequencing. We discuss the identification of disease-relevant repeat element variants, further powered by the advancement of long-read sequencing technologies and their related tools, and summarize recent findings in the molecular mechanisms of repeat element variants in brain degeneration, such as those causing transcriptional silencing or RNA-mediated gain of toxic function. Furthermore, we describe how in silico predictions using innovative computational models, such as deep learning language models, could enhance and accelerate our understanding of the functional impact of repeat element variants. Finally, we discuss future directions to advance current findings for a better understanding of neurodegenerative diseases and the clinical applications of genomic repeat elements.
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Affiliation(s)
- Zhengyu An
- Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, China
| | - Aidi Jiang
- Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, China
| | - Jingqi Chen
- Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, China
- MOE Frontiers Center for Brain Science, Fudan University, Shanghai, China
- MOE Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence, Fudan University, Shanghai, China
- Zhangjiang Fudan International Innovation Center, Shanghai, China
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2
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Geng Y, Liu C, Xu N, Suen MC, Miao H, Xie Y, Zhang B, Chen X, Song Y, Wang Z, Cai Q, Zhu G. Crystal structure of a tetrameric RNA G-quadruplex formed by hexanucleotide repeat expansions of C9orf72 in ALS/FTD. Nucleic Acids Res 2024; 52:7961-7970. [PMID: 38860430 PMCID: PMC11260476 DOI: 10.1093/nar/gkae473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 05/16/2024] [Accepted: 05/29/2024] [Indexed: 06/12/2024] Open
Abstract
The abnormal GGGGCC hexanucleotide repeat expansions (HREs) in C9orf72 cause the fatal neurodegenerative diseases including amyotrophic lateral sclerosis and frontotemporal dementia. The transcribed RNA HREs, short for r(G4C2)n, can form toxic RNA foci which sequestrate RNA binding proteins and impair RNA processing, ultimately leading to neurodegeneration. Here, we determined the crystal structure of r(G4C2)2, which folds into a parallel tetrameric G-quadruplex composed of two four-layer dimeric G-quadruplex via 5'-to-5' stacking in coordination with a K+ ion. Notably, the two C bases locate at 3'- end stack on the outer G-tetrad with the assistance of two additional K+ ions. The high-resolution structure reported here lays a foundation in understanding the mechanism of neurological toxicity of RNA HREs. Furthermore, the atomic details provide a structural basis for the development of potential therapeutic agents against the fatal neurodegenerative diseases ALS/FTD.
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Affiliation(s)
- Yanyan Geng
- Clinical Research Institute of the First Affiliated Hospital of Xiamen University, Fujian Key Laboratory of Brain Tumors Diagnosis and Precision Treatment, Xiamen Key Laboratory of Brain Center, the First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China
- Institute for Advanced Study and State Key Laboratory of Molecular Neuroscience, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
- Department of Neurosurgery and Department of Neuroscience, Fujian Key Laboratory of Brain Tumors Diagnosis and Precision Treatment, Xiamen Key Laboratory of Brain Center, the First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Changdong Liu
- Institute for Advanced Study and State Key Laboratory of Molecular Neuroscience, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
- HKUST Shenzhen Research Institute, Hi-Tech Park, Nanshan, Shenzhen, Guangdong, China
| | - Naining Xu
- Institute for Advanced Study and State Key Laboratory of Molecular Neuroscience, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
- HKUST Shenzhen Research Institute, Hi-Tech Park, Nanshan, Shenzhen, Guangdong, China
| | - Monica Ching Suen
- Institute for Advanced Study and State Key Laboratory of Molecular Neuroscience, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
- HKUST Shenzhen Research Institute, Hi-Tech Park, Nanshan, Shenzhen, Guangdong, China
| | - Haitao Miao
- Institute for Advanced Study and State Key Laboratory of Molecular Neuroscience, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
| | - Yuanyuan Xie
- Department of Neurosurgery and Department of Neuroscience, Fujian Key Laboratory of Brain Tumors Diagnosis and Precision Treatment, Xiamen Key Laboratory of Brain Center, the First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Bingchang Zhang
- Department of Neurosurgery and Department of Neuroscience, Fujian Key Laboratory of Brain Tumors Diagnosis and Precision Treatment, Xiamen Key Laboratory of Brain Center, the First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Xueqin Chen
- Clinical Research Institute of the First Affiliated Hospital of Xiamen University, Fujian Key Laboratory of Brain Tumors Diagnosis and Precision Treatment, Xiamen Key Laboratory of Brain Center, the First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Yuanjian Song
- Jiangsu Key Laboratory of Brain Disease Bioinformation, Department of Genetics, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Zhanxiang Wang
- Department of Neurosurgery and Department of Neuroscience, Fujian Key Laboratory of Brain Tumors Diagnosis and Precision Treatment, Xiamen Key Laboratory of Brain Center, the First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Qixu Cai
- State Key Laboratory of Vaccines for Infectious Diseases, School of Public Health, Xiamen University, Xiamen, Fujian, China
| | - Guang Zhu
- Institute for Advanced Study and State Key Laboratory of Molecular Neuroscience, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
- HKUST Shenzhen Research Institute, Hi-Tech Park, Nanshan, Shenzhen, Guangdong, China
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3
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Buccellato FR, D'Anca M, Tartaglia GM, Del Fabbro M, Galimberti D. Frontotemporal dementia: from genetics to therapeutic approaches. Expert Opin Investig Drugs 2024; 33:561-573. [PMID: 38687620 DOI: 10.1080/13543784.2024.2349286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Accepted: 04/25/2024] [Indexed: 05/02/2024]
Abstract
INTRODUCTION Frontotemporal dementia (FTD) includes a group of neurodegenerative diseases characterized clinically by behavioral disturbances and by neurodegeneration of brain anterior temporal and frontal lobes, leading to atrophy. Apart from symptomatic treatments, there is, at present, no disease-modifying cure for FTD. AREAS COVERED Three main mutations are known as causes of familial FTD, and large consortia have studied carriers of mutations, also in preclinical Phases. As genetic cases are the only ones in which the pathology can be predicted in life, compounds developed so far are directed toward specific proteins or mutations. Herein, recently approved clinical trials will be summarized, including molecules, mechanisms of action and pharmacological testing. EXPERT OPINION These studies are paving the way for the future. They will clarify whether single mutations should be addressed rather than common proteins depositing in the brain to move from genetic to sporadic FTD.
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Affiliation(s)
- Francesca R Buccellato
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, Milan, Italy
- Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Marianna D'Anca
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, Milan, Italy
| | - Gianluca Martino Tartaglia
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, Milan, Italy
- Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Massimo Del Fabbro
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, Milan, Italy
- Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Daniela Galimberti
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, Milan, Italy
- Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
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4
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Hu Y, Chen W, Wei C, Jiang S, Li S, Wang X, Xu R. Pathological mechanisms of amyotrophic lateral Sclerosis. Neural Regen Res 2024; 19:1036-1044. [PMID: 37862206 PMCID: PMC10749610 DOI: 10.4103/1673-5374.382985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Revised: 05/12/2023] [Accepted: 07/06/2023] [Indexed: 10/22/2023] Open
Abstract
Amyotrophic lateral sclerosis refers to a neurodegenerative disease involving the motor system, the cause of which remains unexplained despite several years of research. Thus, the journey to understanding or treating amyotrophic lateral sclerosis is still a long one. According to current research, amyotrophic lateral sclerosis is likely not due to a single factor but rather to a combination of mechanisms mediated by complex interactions between molecular and genetic pathways. The progression of the disease involves multiple cellular processes and the interaction between different complex mechanisms makes it difficult to identify the causative factors of amyotrophic lateral sclerosis. Here, we review the most common amyotrophic lateral sclerosis-associated pathogenic genes and the pathways involved in amyotrophic lateral sclerosis, as well as summarize currently proposed potential mechanisms responsible for amyotrophic lateral sclerosis disease and their evidence for involvement in amyotrophic lateral sclerosis. In addition, we discuss current emerging strategies for the treatment of amyotrophic lateral sclerosis. Studying the emergence of these new therapies may help to further our understanding of the pathogenic mechanisms of the disease.
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Affiliation(s)
- Yushu Hu
- Department of Clinical Medicine, Nanchang University, Nanchang, Jiangxi Province, China
- Department of Neurology, Jiangxi Provincial People’s Hospital, Nanchang, Jiangxi Province, China
| | - Wenzhi Chen
- Department of Clinical Medicine, Nanchang University, Nanchang, Jiangxi Province, China
- Department of Neurology, Jiangxi Provincial People’s Hospital, Nanchang, Jiangxi Province, China
| | - Caihui Wei
- Department of Clinical Medicine, Nanchang University, Nanchang, Jiangxi Province, China
- Department of Neurology, Jiangxi Provincial People’s Hospital, Nanchang, Jiangxi Province, China
| | - Shishi Jiang
- Department of Clinical Medicine, Nanchang University, Nanchang, Jiangxi Province, China
- Department of Neurology, Jiangxi Provincial People’s Hospital, Nanchang, Jiangxi Province, China
| | - Shu Li
- Department of Clinical Medicine, Nanchang University, Nanchang, Jiangxi Province, China
- Department of Neurology, Jiangxi Provincial People’s Hospital, Nanchang, Jiangxi Province, China
| | - Xinxin Wang
- Department of Clinical Medicine, Nanchang University, Nanchang, Jiangxi Province, China
- Department of Neurology, Jiangxi Provincial People’s Hospital, Nanchang, Jiangxi Province, China
| | - Renshi Xu
- Department of Clinical Medicine, Nanchang University, Nanchang, Jiangxi Province, China
- Department of Neurology, Jiangxi Provincial People’s Hospital, Nanchang, Jiangxi Province, China
- Department of Neurology, The First Affiliated Hospital of Nanchang Medical College; The Clinical College of Nanchang Medical College, Nanchang, Jiangxi Province, China
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5
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Sellier C, Corcia P, Vourc'h P, Dupuis L. C9ORF72 hexanucleotide repeat expansion: From ALS and FTD to a broader pathogenic role? Rev Neurol (Paris) 2024; 180:417-428. [PMID: 38609750 DOI: 10.1016/j.neurol.2024.03.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Accepted: 03/30/2024] [Indexed: 04/14/2024]
Abstract
The major gene underlying monogenic forms of amyotrophic lateral sclerosis (ALS) and fronto-temporal dementia (FTD) is C9ORF72. The causative mutation in C9ORF72 is an abnormal hexanucleotide (G4C2) repeat expansion (HRE) located in the first intron of the gene. The aim of this review is to propose a comprehensive update on recent developments on clinical, biological and therapeutics aspects related to C9ORF72 in order to highlight the current understanding of genotype-phenotype correlations, and also on biological machinery leading to neuronal death. We will particularly focus on the broad phenotypic presentation of C9ORF72-related diseases, that goes well beyond the classical phenotypes observed in ALS and FTD patients. Last, we will comment the possible therapeutical hopes for patients carrying a C9ORF72 HRE.
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Affiliation(s)
- C Sellier
- Centre de recherches en biomédecine de Strasbourg, UMR-S1329, Inserm, université de Strasbourg, Strasbourg, France
| | - P Corcia
- UMR 1253 iBrain, Inserm, université de Tours, Tours, France; Centre constitutif de coordination SLA, CHU de Bretonneau, 2, boulevard Tonnelle, 37044 Tours cedex 1, France
| | - P Vourc'h
- UMR 1253 iBrain, Inserm, université de Tours, Tours, France; Service de biochimie et biologie moléculaire, CHU de Tours, Tours, France
| | - L Dupuis
- Centre de recherches en biomédecine de Strasbourg, UMR-S1329, Inserm, université de Strasbourg, Strasbourg, France.
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6
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Cantara S, Simoncelli G, Ricci C. Antisense Oligonucleotides (ASOs) in Motor Neuron Diseases: A Road to Cure in Light and Shade. Int J Mol Sci 2024; 25:4809. [PMID: 38732027 PMCID: PMC11083842 DOI: 10.3390/ijms25094809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 04/23/2024] [Accepted: 04/26/2024] [Indexed: 05/13/2024] Open
Abstract
Antisense oligonucleotides (ASOs) are short oligodeoxynucleotides designed to bind to specific regions of target mRNA. ASOs can modulate pre-mRNA splicing, increase levels of functional proteins, and decrease levels of toxic proteins. ASOs are being developed for the treatment of motor neuron diseases (MNDs), including spinal muscular atrophy (SMA), amyotrophic lateral sclerosis (ALS) and spinal and bulbar muscular atrophy (SBMA). The biggest success has been the ASO known as nusinersen, the first effective therapy for SMA, able to improve symptoms and slow disease progression. Another success is tofersen, an ASO designed to treat ALS patients with SOD1 gene mutations. Both ASOs have been approved by the FDA and EMA. On the other hand, ASO treatment in ALS patients with the C9orf72 gene mutation did not show any improvement in disease progression. The aim of this review is to provide an up-to-date overview of ASO research in MNDs, from preclinical studies to clinical trials and, where available, regulatory approval. We highlight the successes and failures, underline the strengths and limitations of the current ASO research, and suggest possible approaches that could lead to more effective treatments.
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Affiliation(s)
- Silvia Cantara
- Department of Medical, Surgical and Neurological Sciences, University of Siena, 53100 Siena, Italy;
| | - Giorgia Simoncelli
- Unit of Neurology and Clinical Neurophysiology, Department of Neurological and Motor Sciences, Azienda Ospedaliero-Universitaria Senese, 53100 Siena, Italy;
| | - Claudia Ricci
- Department of Medical, Surgical and Neurological Sciences, University of Siena, 53100 Siena, Italy;
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7
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Han X, Xu S, Wang L, Bi Z, Wang D, Bu H, Da J, Liu Y, Tan W. Artificial DNA Framework Channel Modulates Antiapoptotic Behavior in Ischemia-Stressed Cells via Destabilizing Promoter G-Quadruplex. ACS NANO 2024; 18:6147-6161. [PMID: 38372229 DOI: 10.1021/acsnano.3c06563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
Regulating folding/unfolding of gene promoter G-quadruplexes (G4s) is important for understanding the topological changes in genomic DNAs and the biological effects of such changes on important cellular events. Although many G4-stabilizing ligands have been screened out, effective G4-destabilizing ligands are extremely rare, posing a great challenge for illustrating how G4 destabilization affects gene function in living cells under stress, a long-standing question in neuroscience. Herein, we report a distinct methodology able to destabilize gene promoter G4s in ischemia-stressed neural cells by mitigating the ischemia-induced accumulation of intracellular K+ with an artificial membrane-spanning DNA framework channel (DFC). We also show that ischemia-triggered K+ influx is positively correlated to anomalous stabilization of promoter G4s and downregulation of Bcl-2, an antiapoptotic gene with neuroprotective effects against ischemic injury. Intriguingly, the DFC enables rapid transmembrane transport of excessive K+ mediated by the internal G4 filter, leading to the destabilization of endogenous promoter G4 in Bcl-2 and subsequent turnover of gene expression at both transcription and translation levels under ischemia. Consequently, this work enriches our understanding of the biological roles of endogenous G4s and may offer important clues to study the cellular behaviors in response to stress.
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Affiliation(s)
- Xiaoyan Han
- Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Aptamer Engineering Center of Hunan Province, Hunan University, Changsha 410082, China
| | - Shujuan Xu
- Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Aptamer Engineering Center of Hunan Province, Hunan University, Changsha 410082, China
| | - Linlin Wang
- Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Aptamer Engineering Center of Hunan Province, Hunan University, Changsha 410082, China
| | - Zhengyan Bi
- Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Aptamer Engineering Center of Hunan Province, Hunan University, Changsha 410082, China
| | - Dan Wang
- Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Aptamer Engineering Center of Hunan Province, Hunan University, Changsha 410082, China
| | - Huitong Bu
- Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Aptamer Engineering Center of Hunan Province, Hunan University, Changsha 410082, China
| | - Jun Da
- Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Aptamer Engineering Center of Hunan Province, Hunan University, Changsha 410082, China
| | - Yanlan Liu
- Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Aptamer Engineering Center of Hunan Province, Hunan University, Changsha 410082, China
| | - Weihong Tan
- Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Aptamer Engineering Center of Hunan Province, Hunan University, Changsha 410082, China
- The Key Laboratory of Zhejiang Province for Aptamers and Theranostics, Zhejiang Cancer Hospital, Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, China
- Institute of Molecular Medicine (IMM), Renji Hospital, Shanghai Jiao Tong University School of Medicine, and College of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
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8
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Geng Y, Cai Q. Role of C9orf72 hexanucleotide repeat expansions in ALS/FTD pathogenesis. Front Mol Neurosci 2024; 17:1322720. [PMID: 38318532 PMCID: PMC10838790 DOI: 10.3389/fnmol.2024.1322720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 01/04/2024] [Indexed: 02/07/2024] Open
Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are progressive neurological disorders that share neurodegenerative pathways and features. The most prevalent genetic causes of ALS/FTD is the GGGGCC hexanucleotide repeat expansions in the first intron region of the chromosome 9 open reading frame 72 (C9orf72) gene. In this review, we comprehensively summarize the accumulating evidences elucidating the pathogenic mechanism associated with hexanucleotide repeat expansions in ALS/FTD. These mechanisms encompass the structural polymorphism of DNA and transcribed RNA, the formation of RNA foci via phase separation, and the cytoplasmic accumulation and toxicities of dipeptide-repeat proteins. Additionally, the formation of G-quadruplex structures significantly impairs the expression and normal function of the C9orf72 protein. We also discuss the sequestration of specific RNA binding proteins by GGGGCC RNA, which further contributes to the toxicity of C9orf72 hexanucleotide repeat expansions. The deeper understanding of the pathogenic mechanism of hexanucleotide repeat expansions in ALS/FTD provides multiple potential drug targets for these devastating diseases.
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Affiliation(s)
- Yanyan Geng
- Clinical Research Institute of the First Affiliated Hospital of Xiamen University, Fujian Key Laboratory of Brain Tumors Diagnosis and Precision Treatment, Xiamen Key Laboratory of Brain Center, the First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Qixu Cai
- State Key Laboratory of Vaccines for Infectious Diseases, School of Public Health, Xiamen University, Xiamen, Fujian, China
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9
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Lee D, Jeong HC, Kim SY, Chung JY, Cho SH, Kim KA, Cho JH, Ko BS, Cha IJ, Chung CG, Kim ES, Lee SB. A comparison study of pathological features and drug efficacy between Drosophila models of C9orf72 ALS/FTD. Mol Cells 2024; 47:100005. [PMID: 38376483 PMCID: PMC10880080 DOI: 10.1016/j.mocell.2023.12.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 11/11/2023] [Accepted: 11/13/2023] [Indexed: 02/21/2024] Open
Abstract
Amyotrophic lateral sclerosis is a devastating neurodegenerative disease with a complex genetic basis, presenting both in familial and sporadic forms. The hexanucleotide (G4C2) repeat expansion in the C9orf72 gene, which triggers distinct pathogenic mechanisms, has been identified as a major contributor to familial and sporadic Amyotrophic lateral sclerosis cases. Animal models have proven pivotal in understanding these mechanisms; however, discrepancies between models due to variable transgene sequence, expression levels, and toxicity profiles complicate the translation of findings. Herein, we provide a systematic comparison of 7 publicly available Drosophila transgenes modeling the G4C2 expansion under uniform conditions, evaluating variations in their toxicity profiles. Further, we tested 3 previously characterized disease-modifying drugs in selected lines to uncover discrepancies among the tested strains. Our study not only deepens our understanding of the C9orf72 G4C2 mutations but also presents a framework for comparing constructs with minute structural differences. This work may be used to inform experimental designs to better model disease mechanisms and help guide the development of targeted interventions for neurodegenerative diseases, thus bridging the gap between model-based research and therapeutic application.
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Affiliation(s)
- Davin Lee
- Department of Brain Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
| | - Hae Chan Jeong
- Department of Brain Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
| | - Seung Yeol Kim
- SK Biopharmaceuticals Co., Ltd., Seongnam 13494, Republic of Korea
| | - Jin Yong Chung
- SK Biopharmaceuticals Co., Ltd., Seongnam 13494, Republic of Korea
| | - Seok Hwan Cho
- SK Biopharmaceuticals Co., Ltd., Seongnam 13494, Republic of Korea
| | - Kyoung Ah Kim
- Department of Brain Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
| | - Jae Ho Cho
- Department of Brain Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
| | - Byung Su Ko
- Department of Brain Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
| | - In Jun Cha
- Brain Research Policy Center, Korea Brain Research Institute, Daegu 41068, Republic of Korea
| | - Chang Geon Chung
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Eun Seon Kim
- Department of Brain Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
| | - Sung Bae Lee
- Department of Brain Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
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10
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Ortega JA, Sasselli IR, Boccitto M, Fleming AC, Fortuna TR, Li Y, Sato K, Clemons TD, Mckenna ED, Nguyen TP, Anderson EN, Asin J, Ichida JK, Pandey UB, Wolin SL, Stupp SI, Kiskinis E. CLIP-Seq analysis enables the design of protective ribosomal RNA bait oligonucleotides against C9ORF72 ALS/FTD poly-GR pathophysiology. SCIENCE ADVANCES 2023; 9:eadf7997. [PMID: 37948524 PMCID: PMC10637751 DOI: 10.1126/sciadv.adf7997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Accepted: 10/11/2023] [Indexed: 11/12/2023]
Abstract
Amyotrophic lateral sclerosis and frontotemporal dementia patients with a hexanucleotide repeat expansion in C9ORF72 (C9-HRE) accumulate poly-GR and poly-PR aggregates. The pathogenicity of these arginine-rich dipeptide repeats (R-DPRs) is thought to be driven by their propensity to bind low-complexity domains of multivalent proteins. However, the ability of R-DPRs to bind native RNA and the significance of this interaction remain unclear. Here, we used computational and experimental approaches to characterize the physicochemical properties of R-DPRs and their interaction with RNA. We find that poly-GR predominantly binds ribosomal RNA (rRNA) in cells and exhibits an interaction that is predicted to be energetically stronger than that for associated ribosomal proteins. Critically, modified rRNA "bait" oligonucleotides restore poly-GR-associated ribosomal deficits and ameliorate poly-GR toxicity in patient neurons and Drosophila models. Our work strengthens the hypothesis that ribosomal function is impaired by R-DPRs, highlights a role for direct rRNA binding in mediating ribosomal dysfunction, and presents a strategy for protecting against C9-HRE pathophysiological mechanisms.
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Affiliation(s)
- Juan A. Ortega
- The Ken & Ruth Davee Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Department of Pathology and Experimental Therapy, Institute of Neurosciences, University of Barcelona, Barcelona 08907, Spain
| | - Ivan R. Sasselli
- Department of Chemistry, Northwestern University, Evanston, IL 60208, USA
- Simpson Querrey Institute for BioNanotechnology, Northwestern University, Chicago, IL 60611, USA
- Center for Cooperative Research in Biomaterials (CIC biomaGUNE), Basque Research and Technology Alliance (BRTA), Donostia-San Sebastián 20014, Spain
- Centro de Fisica de Materiales (CFM), CSIC-UPV/EHU, 20018 San Sebastián, Spain
| | - Marco Boccitto
- RNA Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA
| | - Andrew C. Fleming
- The Ken & Ruth Davee Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Tyler R. Fortuna
- Department of Pediatrics, Children’s Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
| | - Yichen Li
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Kohei Sato
- Department of Chemistry, Northwestern University, Evanston, IL 60208, USA
- Simpson Querrey Institute for BioNanotechnology, Northwestern University, Chicago, IL 60611, USA
| | - Tristan D. Clemons
- Department of Chemistry, Northwestern University, Evanston, IL 60208, USA
- Simpson Querrey Institute for BioNanotechnology, Northwestern University, Chicago, IL 60611, USA
| | - Elizabeth D. Mckenna
- The Ken & Ruth Davee Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Thao P. Nguyen
- The Ken & Ruth Davee Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Eric N. Anderson
- Department of Pediatrics, Children’s Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
| | - Jesus Asin
- Department of Statistical Methods, School of Engineering, University of Zaragoza, Zaragoza 50018, Spain
| | - Justin K. Ichida
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Udai B. Pandey
- Department of Pediatrics, Children’s Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
| | - Sandra L. Wolin
- RNA Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA
| | - Samuel I. Stupp
- Department of Chemistry, Northwestern University, Evanston, IL 60208, USA
- Simpson Querrey Institute for BioNanotechnology, Northwestern University, Chicago, IL 60611, USA
- Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208, USA
- Department of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Evangelos Kiskinis
- The Ken & Ruth Davee Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Simpson Querrey Institute for BioNanotechnology, Northwestern University, Chicago, IL 60611, USA
- Department of Neuroscience, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
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11
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Beckers J, Tharkeshwar AK, Fumagalli L, Contardo M, Van Schoor E, Fazal R, Thal DR, Chandran S, Mancuso R, Van Den Bosch L, Van Damme P. A toxic gain-of-function mechanism in C9orf72 ALS impairs the autophagy-lysosome pathway in neurons. Acta Neuropathol Commun 2023; 11:151. [PMID: 37723585 PMCID: PMC10506245 DOI: 10.1186/s40478-023-01648-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 08/30/2023] [Indexed: 09/20/2023] Open
Abstract
BACKGROUND Motor neurons (MNs), which are primarily affected in amyotrophic lateral sclerosis (ALS), are a specialized type of neurons that are long and non-dividing. Given their unique structure, these cells heavily rely on transport of organelles along their axons and the process of autophagy to maintain their cellular homeostasis. It has been shown that disruption of the autophagy pathway is sufficient to cause progressive neurodegeneration and defects in autophagy have been associated with various subtypes of ALS, including those caused by hexanucleotide repeat expansions in the C9orf72 gene. A more comprehensive understanding of the dysfunctional cellular mechanisms will help rationalize the design of potent and selective therapies for C9orf72-ALS. METHODS In this study, we used induced pluripotent stem cell (iPSC)-derived MNs from C9orf72-ALS patients and isogenic control lines to identify the underlying mechanisms causing dysregulations of the autophagy-lysosome pathway. Additionally, to ascertain the potential impact of C9orf72 loss-of-function on autophagic defects, we characterized the observed phenotypes in a C9orf72 knockout iPSC line (C9-KO). RESULTS Despite the evident presence of dysfunctions in several aspects of the autophagy-lysosome pathway, such as disrupted lysosomal homeostasis, abnormal lysosome morphology, inhibition of autophagic flux, and accumulation of p62 in C9orf72-ALS MNs, we were surprised to find that C9orf72 loss-of-function had minimal influence on these phenotypes. Instead, we primarily observed impairment in endosome maturation as a result of C9orf72 loss-of-function. Additionally, our study shed light on the pathological mechanisms underlying C9orf72-ALS, as we detected an increased TBK1 phosphorylation at S172 in MNs derived from C9orf72 ALS patients. CONCLUSIONS Our data provides further insight into the involvement of defects in the autophagy-lysosome pathway in C9orf72-ALS and strongly indicate that those defects are mainly due to the toxic gain-of-function mechanisms underlying C9orf72-ALS.
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Affiliation(s)
- Jimmy Beckers
- Department of Neurosciences, Experimental Neurology and Leuven Brain Institute (LBI), KU Louvain - University of Leuven, Leuven, Belgium.
- Center for Brain and Disease Research, Laboratory of Neurobiology, VIB, Leuven, Belgium.
| | - Arun Kumar Tharkeshwar
- Department of Neurosciences, Experimental Neurology and Leuven Brain Institute (LBI), KU Louvain - University of Leuven, Leuven, Belgium
- Center for Brain and Disease Research, Laboratory of Neurobiology, VIB, Leuven, Belgium
- Department of Human Genetics, KU Leuven, Louvain, Belgium
| | - Laura Fumagalli
- Center for Molecular Neurology, Microglia and Inflammation in Neurological Disorders (MIND) Lab, VIB, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Matilde Contardo
- Department of Neurosciences, Experimental Neurology and Leuven Brain Institute (LBI), KU Louvain - University of Leuven, Leuven, Belgium
- Center for Brain and Disease Research, Laboratory of Neurobiology, VIB, Leuven, Belgium
| | - Evelien Van Schoor
- Department of Neurosciences, Experimental Neurology and Leuven Brain Institute (LBI), KU Louvain - University of Leuven, Leuven, Belgium
- Center for Brain and Disease Research, Laboratory of Neurobiology, VIB, Leuven, Belgium
- Laboratory of Neuropathology, Department of Imaging and Pathology, Leuven Brain Institute (LBI), KU Louvain - University of Leuven, Leuven, Belgium
| | - Raheem Fazal
- Department of Neurosciences, Experimental Neurology and Leuven Brain Institute (LBI), KU Louvain - University of Leuven, Leuven, Belgium
- Center for Brain and Disease Research, Laboratory of Neurobiology, VIB, Leuven, Belgium
| | - Dietmar Rudolf Thal
- Laboratory of Neuropathology, Department of Imaging and Pathology, Leuven Brain Institute (LBI), KU Louvain - University of Leuven, Leuven, Belgium
- Department of Pathology, University Hospitals Leuven, Louvain, Belgium
| | - Siddharthan Chandran
- UK Dementia Research Institute, University of Edinburgh, Edinburgh, EH16 4SB, UK
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, EH16 4SB, UK
| | - Renzo Mancuso
- Center for Molecular Neurology, Microglia and Inflammation in Neurological Disorders (MIND) Lab, VIB, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Ludo Van Den Bosch
- Department of Neurosciences, Experimental Neurology and Leuven Brain Institute (LBI), KU Louvain - University of Leuven, Leuven, Belgium
- Center for Brain and Disease Research, Laboratory of Neurobiology, VIB, Leuven, Belgium
| | - Philip Van Damme
- Department of Neurosciences, Experimental Neurology and Leuven Brain Institute (LBI), KU Louvain - University of Leuven, Leuven, Belgium.
- Center for Brain and Disease Research, Laboratory of Neurobiology, VIB, Leuven, Belgium.
- Department of Neurology, University Hospitals Leuven, Louvain, Belgium.
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12
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Malnar Črnigoj M, Čerček U, Yin X, Ho MT, Repic Lampret B, Neumann M, Hermann A, Rouleau G, Suter B, Mayr M, Rogelj B. Phenylalanine-tRNA aminoacylation is compromised by ALS/FTD-associated C9orf72 C4G2 repeat RNA. Nat Commun 2023; 14:5764. [PMID: 37717009 PMCID: PMC10505166 DOI: 10.1038/s41467-023-41511-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 09/07/2023] [Indexed: 09/18/2023] Open
Abstract
The expanded hexanucleotide GGGGCC repeat mutation in the C9orf72 gene is the main genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia. Under one disease mechanism, sense and antisense transcripts of the repeat are predicted to bind various RNA-binding proteins, compromise their function and cause cytotoxicity. Here we identify phenylalanine-tRNA synthetase (FARS) subunit alpha (FARSA) as the main interactor of the CCCCGG antisense repeat RNA in cytosol. The aminoacylation of tRNAPhe by FARS is inhibited by antisense RNA, leading to decreased levels of charged tRNAPhe. Remarkably, this is associated with global reduction of phenylalanine incorporation in the proteome and decrease in expression of phenylalanine-rich proteins in cellular models and patient tissues. In conclusion, this study reveals functional inhibition of FARSA in the presence of antisense RNA repeats. Compromised aminoacylation of tRNA could lead to impairments in protein synthesis and further contribute to C9orf72 mutation-associated pathology.
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Affiliation(s)
- Mirjana Malnar Črnigoj
- Department of Biotechnology, Jožef Stefan Institute, Ljubljana, 1000, Slovenia
- Graduate School of Biomedicine, Faculty of Medicine, University of Ljubljana, Ljubljana, 1000, Slovenia
| | - Urša Čerček
- Department of Biotechnology, Jožef Stefan Institute, Ljubljana, 1000, Slovenia
- Graduate School of Biomedicine, Faculty of Medicine, University of Ljubljana, Ljubljana, 1000, Slovenia
| | - Xiaoke Yin
- King's BHF Centre, King's College London, London, SE5 9NU, UK
| | - Manh Tin Ho
- Institute of Cell Biology, University of Bern, Bern, 3012, Switzerland
| | - Barbka Repic Lampret
- Clinical Institute of Special Laboratory Diagnostics, University Children's Hospital, University Medical Centre Ljubljana, Ljubljana, 1000, Slovenia
| | - Manuela Neumann
- Molecular Neuropathology of Neurodegenerative Diseases, German Center for Neurodegenerative Diseases, Tübingen, 72076, Germany
- Department of Neuropathology, University Hospital of Tübingen, Tübingen, 72076, Germany
| | - Andreas Hermann
- Translational Neurodegeneration Section "Albrecht-Kossel", Department of Neurology and Center for Transdisciplinary Neurosciences Rostock (CTNR), University Medical Center Rostock, University of Rostock, 18147, Rostock, Germany
- Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE), Rostock/Greifswald, 18147, Rostock, Germany
| | - Guy Rouleau
- Department of Human Genetics, McGill University, Montréal, QC, H3A 0G4, Canada
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montréal, QC, H3A 0G4, Canada
| | - Beat Suter
- Institute of Cell Biology, University of Bern, Bern, 3012, Switzerland
| | - Manuel Mayr
- King's BHF Centre, King's College London, London, SE5 9NU, UK
| | - Boris Rogelj
- Department of Biotechnology, Jožef Stefan Institute, Ljubljana, 1000, Slovenia.
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ljubljana, 1000, Slovenia.
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13
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Bagyinszky E, Hulme J, An SSA. Studies of Genetic and Proteomic Risk Factors of Amyotrophic Lateral Sclerosis Inspire Biomarker Development and Gene Therapy. Cells 2023; 12:1948. [PMID: 37566027 PMCID: PMC10417729 DOI: 10.3390/cells12151948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 07/21/2023] [Accepted: 07/25/2023] [Indexed: 08/12/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is an incurable neurodegenerative disease affecting the upper and lower motor neurons, leading to muscle weakness, motor impairments, disabilities and death. Approximately 5-10% of ALS cases are associated with positive family history (familial ALS or fALS), whilst the remainder are sporadic (sporadic ALS, sALS). At least 50 genes have been identified as causative or risk factors for ALS. Established pathogenic variants include superoxide dismutase type 1 (SOD1), chromosome 9 open reading frame 72 (c9orf72), TAR DNA Binding Protein (TARDBP), and Fused In Sarcoma (FUS); additional ALS-related genes including Charged Multivesicular Body Protein 2B (CHMP2B), Senataxin (SETX), Sequestosome 1 (SQSTM1), TANK Binding Kinase 1 (TBK1) and NIMA Related Kinase 1 (NEK1), have been identified. Mutations in these genes could impair different mechanisms, including vesicle transport, autophagy, and cytoskeletal or mitochondrial functions. So far, there is no effective therapy against ALS. Thus, early diagnosis and disease risk predictions remain one of the best options against ALS symptomologies. Proteomic biomarkers, microRNAs, and extracellular vehicles (EVs) serve as promising tools for disease diagnosis or progression assessment. These markers are relatively easy to obtain from blood or cerebrospinal fluids and can be used to identify potential genetic causative and risk factors even in the preclinical stage before symptoms appear. In addition, antisense oligonucleotides and RNA gene therapies have successfully been employed against other diseases, such as childhood-onset spinal muscular atrophy (SMA), which could also give hope to ALS patients. Therefore, an effective gene and biomarker panel should be generated for potentially "at risk" individuals to provide timely interventions and better treatment outcomes for ALS patients as soon as possible.
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Affiliation(s)
- Eva Bagyinszky
- Graduate School of Environment Department of Industrial and Environmental Engineering, Gachon University, Seongnam-si 13120, Republic of Korea;
| | - John Hulme
- Graduate School of Environment Department of Industrial and Environmental Engineering, Gachon University, Seongnam-si 13120, Republic of Korea;
| | - Seong Soo A. An
- Department of Bionano Technology, Gachon University, Seongnam-si 13120, Republic of Korea
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14
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Viera Ortiz AP, Cajka G, Olatunji OA, Mikytuck B, Shalem O, Lee EB. Impaired ribosome-associated quality control of C9orf72 arginine-rich dipeptide-repeat proteins. Brain 2023; 146:2897-2912. [PMID: 36516294 PMCID: PMC10316761 DOI: 10.1093/brain/awac479] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 11/05/2022] [Accepted: 12/06/2022] [Indexed: 12/15/2022] Open
Abstract
Protein quality control pathways have evolved to ensure the fidelity of protein synthesis and efficiently clear potentially toxic protein species. Defects in ribosome-associated quality control and its associated factors have been implicated in the accumulation of aberrant proteins and neurodegeneration. C9orf72 repeat-associated non-AUG translation has been suggested to involve inefficient translation elongation, lead to ribosomal pausing and activation of ribosome-associated quality control pathways. However, the role of the ribosome-associated quality control complex in the processing of proteins generated through this non-canonical translation is not well understood. Here we use reporter constructs containing the C9orf72-associated hexanucleotide repeat, ribosome-associated quality control complex deficient cell models and stain for ribosome-associated quality control markers in C9orf72-expansion carrier human tissue to understand its role in dipeptide-repeat protein pathology. Our studies show that canonical ribosome-associated quality control substrates products are efficiently cleared by the ribosome-associated quality control complex in mammalian cells. Furthermore, using stalling reporter constructs, we show that repeats associated with the C9orf72-expansion induce ribosomal stalling when arginine (R)-rich dipeptide-repeat proteins are synthesized in a length-dependent manner. However, despite triggering this pathway, these arginine-rich dipeptide-repeat proteins are not efficiently processed by the core components of the ribosome-associated quality control complex (listerin, nuclear-export mediator factor and valosin containing protein) partly due to lack of lysine residues, which precludes ubiquitination. Deficient processing by this complex may be implicated in C9orf72-expansion associated disease as dipeptide-repeat protein inclusions were observed to be predominantly devoid of ubiquitin and co-localize with nuclear-export mediator factor in mutation carriers' frontal cortex and cerebellum tissue. These findings suggest that impaired processing of these arginine-rich dipeptide-repeat proteins derived from repeat-associated non-AUG translation by the ribosome-associated quality control complex may contribute to protein homeostasis dysregulation observed in C9orf72-expansion amyotrophic lateral sclerosis and frontotemporal degeneration neuropathogenesis.
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Affiliation(s)
- Ashley P Viera Ortiz
- Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
- Translational Neuropathology Research Laboratory, Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Gregory Cajka
- Center for Cellular and Molecular Therapeutics, Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
- Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Olamide A Olatunji
- Translational Neuropathology Research Laboratory, Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Bailey Mikytuck
- Translational Neuropathology Research Laboratory, Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ophir Shalem
- Center for Cellular and Molecular Therapeutics, Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
- Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Edward B Lee
- Translational Neuropathology Research Laboratory, Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
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15
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Allen SP, Al Sultan A, Kabucho Kibirige E, Tonkiss E, Hamer KJ, Castelli LM, Lin YH, Roscoe S, Stefanidis N, Mead RJ, Highley JR, Cooper-Knock J, Hautbergue GM, Heath PR, Kirby J, Shaw PJ. A Y374X TDP43 truncation leads to an altered metabolic profile in amyotrophic lateral sclerosis fibroblasts driven by pyruvate and TCA cycle intermediate alterations. Front Aging Neurosci 2023; 15:1151848. [PMID: 37251807 PMCID: PMC10213779 DOI: 10.3389/fnagi.2023.1151848] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 04/18/2023] [Indexed: 05/31/2023] Open
Abstract
A p.Y374X truncation in TARDBP was recently shown to reduce expression of TDP43 in fibroblasts isolated from ALS cases. In this follow up study focused on assessing the downstream phenotypic consequences of loss of TDP43 in the context of the truncation, we have shown a striking effect on the fibroblast metabolic profile. Phenotypic metabolic screening uncovered a distinct metabolic profile in TDP43-Y374X fibroblasts compared to controls, which was driven by alterations in key metabolic checkpoint intermediates including pyruvate, alpha-ketoglutarate and succinate. These metabolic alterations were confirmed using transcriptomics and bioenergetic flux analysis. These data suggest that TDP43 truncation directly compromises glycolytic and mitochondrial function, identifying potential therapeutic targets for mitigating the effects of TDP43-Y374X truncation.
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Affiliation(s)
- Scott P. Allen
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, United Kingdom
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16
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Tu WY, Xu W, Zhang J, Qi S, Bai L, Shen C, Zhang K. C9orf72 poly-GA proteins impair neuromuscular transmission. Zool Res 2023; 44:331-340. [PMID: 36799225 PMCID: PMC10083233 DOI: 10.24272/j.issn.2095-8137.2022.356] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 02/15/2023] [Indexed: 02/18/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a devastating motoneuron disease, in which lower motoneurons lose control of skeletal muscles. Degeneration of neuromuscular junctions (NMJs) occurs at the initial stage of ALS. Dipeptide repeat proteins (DPRs) from G4C2 repeat-associated non-ATG (RAN) translation are known to cause C9orf72-associated ALS (C9-ALS). However, DPR inclusion burdens are weakly correlated with neurodegenerative areas in C9-ALS patients, indicating that DPRs may exert cell non-autonomous effects, in addition to the known intracellular pathological mechanisms. Here, we report that poly-GA, the most abundant form of DPR in C9-ALS, is released from cells. Local administration of poly-GA proteins in peripheral synaptic regions causes muscle weakness and impaired neuromuscular transmission in vivo. The NMJ structure cannot be maintained, as evidenced by the fragmentation of postsynaptic acetylcholine receptor (AChR) clusters and distortion of presynaptic nerve terminals. Mechanistic study demonstrated that extracellular poly-GA sequesters soluble Agrin ligands and inhibits Agrin-MuSK signaling. Our findings provide a novel cell non-autonomous mechanism by which poly-GA impairs NMJs in C9-ALS. Thus, targeting NMJs could be an early therapeutic intervention for C9-ALS.
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Affiliation(s)
- Wen-Yo Tu
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, Department of Neurobiology, First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310020, China
| | - Wentao Xu
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, Department of Neurobiology, First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310020, China
| | - Jianmin Zhang
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, Department of Neurobiology, First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310020, China
| | - Shuyuan Qi
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, Department of Neurobiology, First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310020, China
| | - Lei Bai
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, Department of Neurobiology, First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310020, China
| | - Chengyong Shen
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, Department of Neurobiology, First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310020, China
- MOE Frontier Science, Center for Brain Research and Brain-Machine Integration, Zhejiang University, Hangzhou, Zhejiang 310058, China. E-mail:
| | - Kejing Zhang
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, Department of Neurobiology, First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310020, China. E-mail:
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17
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Diab R, Pilotto F, Saxena S. Autophagy and neurodegeneration: Unraveling the role of C9ORF72 in the regulation of autophagy and its relationship to ALS-FTD pathology. Front Cell Neurosci 2023; 17:1086895. [PMID: 37006471 PMCID: PMC10060823 DOI: 10.3389/fncel.2023.1086895] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Accepted: 03/01/2023] [Indexed: 03/18/2023] Open
Abstract
The proper functioning of the cell clearance machinery is critical for neuronal health within the central nervous system (CNS). In normal physiological conditions, the cell clearance machinery is actively involved in the elimination of misfolded and toxic proteins throughout the lifetime of an organism. The highly conserved and regulated pathway of autophagy is one of the important processes involved in preventing and neutralizing pathogenic buildup of toxic proteins that could eventually lead to the development of neurodegenerative diseases (NDs) such as Alzheimer’s disease or Amyotrophic lateral sclerosis (ALS). The most common genetic cause of ALS and frontotemporal dementia (FTD) is a hexanucleotide expansion consisting of GGGGCC (G4C2) repeats in the chromosome 9 open reading frame 72 gene (C9ORF72). These abnormally expanded repeats have been implicated in leading to three main modes of disease pathology: loss of function of the C9ORF72 protein, the generation of RNA foci, and the production of dipeptide repeat proteins (DPRs). In this review, we discuss the normal physiological role of C9ORF72 in the autophagy-lysosome pathway (ALP), and present recent research deciphering how dysfunction of the ALP synergizes with C9ORF72 haploinsufficiency, which together with the gain of toxic mechanisms involving hexanucleotide repeat expansions and DPRs, drive the disease process. This review delves further into the interactions of C9ORF72 with RAB proteins involved in endosomal/lysosomal trafficking, and their role in regulating various steps in autophagy and lysosomal pathways. Lastly, the review aims to provide a framework for further investigations of neuronal autophagy in C9ORF72-linked ALS-FTD as well as other neurodegenerative diseases.
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Affiliation(s)
- Rim Diab
- Department of Neurology, Center for Experimental Neurology, Inselspital University Hospital, Bern, Switzerland
- Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Federica Pilotto
- Department of Neurology, Center for Experimental Neurology, Inselspital University Hospital, Bern, Switzerland
- Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Smita Saxena
- Department of Neurology, Center for Experimental Neurology, Inselspital University Hospital, Bern, Switzerland
- Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
- *Correspondence: Smita Saxena,
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18
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Martella N, Pensabene D, Varone M, Colardo M, Petraroia M, Sergio W, La Rosa P, Moreno S, Segatto M. Bromodomain and Extra-Terminal Proteins in Brain Physiology and Pathology: BET-ing on Epigenetic Regulation. Biomedicines 2023; 11:biomedicines11030750. [PMID: 36979729 PMCID: PMC10045827 DOI: 10.3390/biomedicines11030750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 02/24/2023] [Accepted: 02/25/2023] [Indexed: 03/06/2023] Open
Abstract
BET proteins function as histone code readers of acetylated lysins that determine the positive regulation in transcription of genes involved in cell cycle progression, differentiation, inflammation, and many other pathways. In recent years, thanks to the development of BET inhibitors, interest in this protein family has risen for its relevance in brain development and function. For example, experimental evidence has shown that BET modulation affects neuronal activity and the expression of genes involved in learning and memory. In addition, BET inhibition strongly suppresses molecular pathways related to neuroinflammation. These observations suggest that BET modulation may play a critical role in the onset and during the development of diverse neurodegenerative and neuropsychiatric disorders, such as Alzheimer’s disease, fragile X syndrome, and Rett syndrome. In this review article, we summarize the most recent evidence regarding the involvement of BET proteins in brain physiology and pathology, as well as their pharmacological potential as targets for therapeutic purposes.
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Affiliation(s)
- Noemi Martella
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
| | - Daniele Pensabene
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
- Department of Science, University Roma Tre, Viale Marconi 446, 00146 Rome, Italy
- Laboratory of Neurodevelopment, Neurogenetics and Neuromolecular Biology, IRCCS Santa Lucia Foundation, 64 via del Fosso di Fiorano, 00179 Rome, Italy
| | - Michela Varone
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
| | - Mayra Colardo
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
| | - Michele Petraroia
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
| | - William Sergio
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
| | - Piergiorgio La Rosa
- Division of Neuroscience, Department of Psychology, Sapienza University of Rome, via dei Marsi 78, 00185 Rome, Italy
| | - Sandra Moreno
- Department of Science, University Roma Tre, Viale Marconi 446, 00146 Rome, Italy
- Laboratory of Neurodevelopment, Neurogenetics and Neuromolecular Biology, IRCCS Santa Lucia Foundation, 64 via del Fosso di Fiorano, 00179 Rome, Italy
| | - Marco Segatto
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
- Correspondence:
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19
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Wilson DM, Cookson MR, Van Den Bosch L, Zetterberg H, Holtzman DM, Dewachter I. Hallmarks of neurodegenerative diseases. Cell 2023; 186:693-714. [PMID: 36803602 DOI: 10.1016/j.cell.2022.12.032] [Citation(s) in RCA: 292] [Impact Index Per Article: 292.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 11/23/2022] [Accepted: 12/19/2022] [Indexed: 02/18/2023]
Abstract
Decades of research have identified genetic factors and biochemical pathways involved in neurodegenerative diseases (NDDs). We present evidence for the following eight hallmarks of NDD: pathological protein aggregation, synaptic and neuronal network dysfunction, aberrant proteostasis, cytoskeletal abnormalities, altered energy homeostasis, DNA and RNA defects, inflammation, and neuronal cell death. We describe the hallmarks, their biomarkers, and their interactions as a framework to study NDDs using a holistic approach. The framework can serve as a basis for defining pathogenic mechanisms, categorizing different NDDs based on their primary hallmarks, stratifying patients within a specific NDD, and designing multi-targeted, personalized therapies to effectively halt NDDs.
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Affiliation(s)
- David M Wilson
- Hasselt University, Biomedical Research Institute, BIOMED, 3500 Hasselt, Belgium.
| | - Mark R Cookson
- Laboratory of Neurogenetics, National Institute on Aging, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ludo Van Den Bosch
- KU Leuven, University of Leuven, Department of Neurosciences, Experimental Neurology and Leuven Brain Institute (LBI), 3000 Leuven, Belgium; VIB, Center for Brain & Disease Research, Laboratory of Neurobiology, 3000 Leuven, Belgium
| | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden; Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden; Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, UK; UK Dementia Research Institute at UCL, London, UK; Hong Kong Center for Neurodegenerative Diseases, Clear Water Bay, Hong Kong, China; UW Department of Medicine, School of Medicine and Public Health, Madison, WI, USA
| | - David M Holtzman
- Department of Neurology, Hope Center for Neurological Disorders, Knight Alzheimer's Disease Research Center, Washington University in St. Louis, St. Louis, MO, USA
| | - Ilse Dewachter
- Hasselt University, Biomedical Research Institute, BIOMED, 3500 Hasselt, Belgium.
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20
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Li Y, Geng J, Rimal S, Wang H, Liu X, Lu B, Li S. The mTORC2/AKT/VCP axis is associated with quality control of the stalled translation of poly(GR) dipeptide repeats in C9-ALS/FTD. J Biol Chem 2023; 299:102995. [PMID: 36764521 PMCID: PMC10011831 DOI: 10.1016/j.jbc.2023.102995] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/30/2023] [Accepted: 01/31/2023] [Indexed: 02/11/2023] Open
Abstract
Expansion of G4C2 hexanucleotide repeats in the chromosome 9 ORF 72 (C9ORF72) gene is the most common genetic cause of amyotrophic lateral sclerosis (ALS) with frontotemporal dementia (C9-ALS/FTD). Dipeptide repeats generated by unconventional translation, especially the R-containing poly(GR), have been implicated in C9-ALS/FTD pathogenesis. Mutations in other genes, including TAR DNA-binding protein 43 KD (TDP-43), fused in sarcoma (FUS), and valosin-containing protein, have also been linked to ALS/FTD, and upregulation of amyloid precursor protein (APP) is observed at the early stage of ALS and FTD. Fundamental questions remain as to the relationships between these ALS/FTD genes and whether they converge on similar cellular pathways. Here, using biochemical, cell biological, and genetic analyses in Drosophila disease models, patient-derived fibroblasts, and mammalian cell culture, we show that mechanistic target of rapamycin complex 2 (mTORC2)/AKT signaling is activated by APP, TDP-43, and FUS and that mTORC2/AKT and its downstream target valosin-containing protein mediate the effect of APP, TDP-43, and FUS on the quality control of C9-ALS/FTD-associated poly(GR) translation. We also find that poly(GR) expression results in reduction of global translation and that the coexpression of APP, TDP-43, and FUS results in further reduction of global translation, presumably through the GCN2/eIF2α-integrated stress response pathway. Together, our results implicate mTORC2/AKT signaling and GCN2/eIF2α-integrated stress response as common signaling pathways underlying ALS/FTD pathogenesis.
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Affiliation(s)
- Yu Li
- Shandong Provincial Key Laboratory of Animal Cell and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China
| | - Ji Geng
- Shandong Provincial Key Laboratory of Animal Cell and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China; Department of Pathology, Stanford University School of Medicine, Stanford, California, USA
| | - Suman Rimal
- Department of Pathology, Stanford University School of Medicine, Stanford, California, USA
| | - Haochuan Wang
- Shandong Provincial Key Laboratory of Animal Cell and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China
| | - Xiangguo Liu
- Shandong Provincial Key Laboratory of Animal Cell and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China
| | - Bingwei Lu
- Department of Pathology, Stanford University School of Medicine, Stanford, California, USA.
| | - Shuangxi Li
- Shandong Provincial Key Laboratory of Animal Cell and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China.
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21
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Teng Y, Zhu M, Qiu Z. G-Quadruplexes in Repeat Expansion Disorders. Int J Mol Sci 2023; 24:ijms24032375. [PMID: 36768697 PMCID: PMC9916761 DOI: 10.3390/ijms24032375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 01/19/2023] [Accepted: 01/23/2023] [Indexed: 01/27/2023] Open
Abstract
The repeat expansions are the main genetic cause of various neurodegeneration diseases. More than ten kinds of repeat sequences with different lengths, locations, and structures have been confirmed in the past two decades. G-rich repeat sequences, such as CGG and GGGGCC, are reported to form functional G-quadruplexes, participating in many important bioprocesses. In this review, we conducted an overview concerning the contribution of G-quadruplex in repeat expansion disorders and summarized related mechanisms in current pathological studies, including the increasing genetic instabilities in replication and transcription, the toxic RNA foci formed in neurons, and the loss/gain function of proteins and peptides. Furthermore, novel strategies targeting G-quadruplex repeats were developed based on the understanding of disease mechanism. Small molecules and proteins binding to G-quadruplex in repeat expansions were investigated to protect neurons from dysfunction and delay the progression of neurodegeneration. In addition, the effects of environment on the stability of G-quadruplex were discussed, which might be critical factors in the pathological study of repeat expansion disorders.
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22
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Millar SR, Huang JQ, Schreiber KJ, Tsai YC, Won J, Zhang J, Moses AM, Youn JY. A New Phase of Networking: The Molecular Composition and Regulatory Dynamics of Mammalian Stress Granules. Chem Rev 2023. [PMID: 36662637 PMCID: PMC10375481 DOI: 10.1021/acs.chemrev.2c00608] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Stress granules (SGs) are cytosolic biomolecular condensates that form in response to cellular stress. Weak, multivalent interactions between their protein and RNA constituents drive their rapid, dynamic assembly through phase separation coupled to percolation. Though a consensus model of SG function has yet to be determined, their perceived implication in cytoprotective processes (e.g., antiviral responses and inhibition of apoptosis) and possible role in the pathogenesis of various neurodegenerative diseases (e.g., amyotrophic lateral sclerosis and frontotemporal dementia) have drawn great interest. Consequently, new studies using numerous cell biological, genetic, and proteomic methods have been performed to unravel the mechanisms underlying SG formation, organization, and function and, with them, a more clearly defined SG proteome. Here, we provide a consensus SG proteome through literature curation and an update of the user-friendly database RNAgranuleDB to version 2.0 (http://rnagranuledb.lunenfeld.ca/). With this updated SG proteome, we use next-generation phase separation prediction tools to assess the predisposition of SG proteins for phase separation and aggregation. Next, we analyze the primary sequence features of intrinsically disordered regions (IDRs) within SG-resident proteins. Finally, we review the protein- and RNA-level determinants, including post-translational modifications (PTMs), that regulate SG composition and assembly/disassembly dynamics.
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Affiliation(s)
- Sean R Millar
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Jie Qi Huang
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Karl J Schreiber
- Program in Molecular Medicine, The Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada
| | - Yi-Cheng Tsai
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Jiyun Won
- Department of Cell & Systems Biology, University of Toronto, Toronto, Ontario M5S 3B2, Canada
| | - Jianping Zhang
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, Ontario M5G 1X5, Canada
| | - Alan M Moses
- Department of Cell & Systems Biology, University of Toronto, Toronto, Ontario M5S 3B2, Canada.,Department of Computer Science, University of Toronto, Toronto, Ontario M5T 3A1, Canada.,The Centre for the Analysis of Genome Evolution and Function, University of Toronto, Toronto, Ontario M5S 3B2, Canada
| | - Ji-Young Youn
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada.,Program in Molecular Medicine, The Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada
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23
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Muzio L, Ghirelli A, Agosta F, Martino G. Novel therapeutic approaches for motor neuron disease. HANDBOOK OF CLINICAL NEUROLOGY 2023; 196:523-537. [PMID: 37620088 DOI: 10.1016/b978-0-323-98817-9.00027-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/26/2023]
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that leads to the neurodegeneration and death of upper and lower motor neurons (MNs). Although MNs are the main cells involved in the process of neurodegeneration, a growing body of evidence points toward other cell types as concurrent to disease initiation and propagation. Given the current absence of effective therapies, the quest for other therapeutic targets remains open and still challenges the scientific community. Both neuronal and extra-neuronal mechanisms of cellular stress and damage have been studied and have posed the basis for the development of novel therapies that have been investigated on both animal models and humans. In this chapter, a thorough review of the main mechanisms of cellular damage and the respective therapeutic attempts targeting them is reported. The main areas covered include neuroinflammation, protein aggregation, RNA metabolism, and oxidative stress.
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Affiliation(s)
- Luca Muzio
- San Raffaele Scientific Institute, Division of Neuroscience, InsPE, Milan, Italy
| | - Alma Ghirelli
- San Raffaele Scientific Institute, Division of Neuroscience, InsPE, Milan, Italy; Vita-Salute San Raffaele University, Milan, Italy
| | - Federica Agosta
- San Raffaele Scientific Institute, Division of Neuroscience, InsPE, Milan, Italy; Vita-Salute San Raffaele University, Milan, Italy
| | - Gianvito Martino
- San Raffaele Scientific Institute, Division of Neuroscience, InsPE, Milan, Italy; Vita-Salute San Raffaele University, Milan, Italy
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24
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Kartanou C, Kontogeorgiou Z, Rentzos M, Potagas C, Aristeidou S, Kapaki E, Paraskevas GP, Constantinides VC, Stefanis L, Papageorgiou SG, Houlden H, Panas M, Koutsis G, Karadima G. Expanding the spectrum of C9ORF72-related neurodegenerative disorders in the Greek population. J Neurol Sci 2022; 442:120450. [PMID: 36252286 DOI: 10.1016/j.jns.2022.120450] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 09/26/2022] [Accepted: 10/01/2022] [Indexed: 10/31/2022]
Abstract
The C9ORF72 hexanucleotide repeat expansion is an established cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) and has also been associated with Huntington disease (HD)-like syndromes and rarely with Parkinson's disease (PD) and Alzheimer's disease (AD). In the present study we aimed to investigate the genotypic and phenotypic profile of C9ORF72-related disorders in Greece. For this reason, 957 patients (467 with ALS, 53 with HD-like syndromes, 247 with dementia, 175 with PD and 15 with hereditary spastic paraplegia, HSP) and 321 controls were tested for the C9ORF72 repeat expansion. Forty-nine patients with ALS (10.5%), 2 with HD-like syndromes (3.8%), 13 with FTD (11.5%), 1 with AD (1.6%), and 2 with PD (1.1%) were expansion-positive. The expansion was not detected in the HSP or control groups. The results of this study provide an update on the spectrum of C9ORF72-related neurodegenerative diseases, emphasizing the importance of C9ORF72 genetic testing in Greek patients with familial and sporadic ALS and/or FTD and HD-like syndromes.
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Affiliation(s)
- Chrisoula Kartanou
- Neurogenetics Unit, 1st Department of Neurology, School of Medicine, Eginition Hospital, National and Kapodistrian University of Athens, Athens, Greece.
| | - Zoi Kontogeorgiou
- Neurogenetics Unit, 1st Department of Neurology, School of Medicine, Eginition Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Michail Rentzos
- 1st Department of Neurology, School of Medicine, Eginition Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Constantin Potagas
- Neuropsychology and Speech Pathology Unit, 1st Department of Neurology, School of Medicine, Eginition Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Stavroula Aristeidou
- Neurogenetics Unit, 1st Department of Neurology, School of Medicine, Eginition Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Elisabeth Kapaki
- Unit of Neurochemistry and Biological Markers, 1st Department of Neurology, School of Medicine, Eginition Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - George P Paraskevas
- Unit of Neurochemistry and Biological Markers, 1st Department of Neurology, School of Medicine, Eginition Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Vasilios C Constantinides
- Unit of Neurochemistry and Biological Markers, 1st Department of Neurology, School of Medicine, Eginition Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Leonidas Stefanis
- 1st Department of Neurology, School of Medicine, Eginition Hospital, National and Kapodistrian University of Athens, Athens, Greece; Center of Clinical Research, Experimental Surgery and Translational Research, Biomedical Research Foundation of the Academy of Athens, Greece
| | - Sokratis G Papageorgiou
- 1st Department of Neurology, School of Medicine, Eginition Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Henry Houlden
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, UK
| | - Marios Panas
- Neurogenetics Unit, 1st Department of Neurology, School of Medicine, Eginition Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Georgios Koutsis
- Neurogenetics Unit, 1st Department of Neurology, School of Medicine, Eginition Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Georgia Karadima
- Neurogenetics Unit, 1st Department of Neurology, School of Medicine, Eginition Hospital, National and Kapodistrian University of Athens, Athens, Greece
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25
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Li X, Lu S, Lu B, Sun X. Optogenetic control of GGGGCC repeat-containing RNA phase transition. FUNDAMENTAL RESEARCH 2022; 2:843-850. [PMID: 38933387 PMCID: PMC11197711 DOI: 10.1016/j.fmre.2022.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 08/31/2022] [Accepted: 09/02/2022] [Indexed: 11/21/2022] Open
Abstract
The GGGGCC (G4C2) hexanucleotide repeat expansion in the C9ORF72 gene is a major cause of both hereditary amyotrophic lateral sclerosis and familial frontotemporal dementia. Recent studies have shown that G4C2 hexanucleotide repeat-containing RNA transcripts ((G4C2)n RNA) could go through liquid-liquid phase separation to form RNA foci, which may elicit neurodegeneration. However, the direct causality between these abnormal RNA foci and neuronal toxicity remains to be demonstrated. Here we introduce an optogenetic control system that can induce the assembly and phase separation of (G4C2)n RNA foci with blue light illumination in human cells, by fusing a specific (G4C2)n RNA binding protein as the linker domain to Cry2, a protein that oligomerizes in response to blue light. Our results demonstrate that a higher number of G4C2 repeats have the potential to be induced into more RNA foci in the cells. Both spontaneous and induced RNA foci display liquid-like properties according to FRAP measurements. Computational simulation shows strong consistency with the experimental results and supports the effect of our system to promote the propensity of (G4C2)n RNA towards phase separation. This system can thus be used to investigate whether (G4C2)n RNA foci would disrupt normal cellular processes and lead to pathological phenotypes relevant to repeat expansion disorders.
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Affiliation(s)
- Xiong Li
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Biomedical Sciences, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Shengyi Lu
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Biomedical Sciences, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Boxun Lu
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Biomedical Sciences, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Xiaoli Sun
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Biomedical Sciences, School of Life Sciences, Fudan University, Shanghai 200438, China
- Shanghai Xuhui Central Hospital, Zhongshan-Xuhui Hospital, Fudan University, Shanghai 200031, China
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26
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Ghaffari LT, Trotti D, Haeusler AR, Jensen BK. Breakdown of the central synapses in C9orf72-linked ALS/FTD. Front Mol Neurosci 2022; 15:1005112. [PMID: 36187344 PMCID: PMC9523884 DOI: 10.3389/fnmol.2022.1005112] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 08/29/2022] [Indexed: 01/07/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive, fatal neurodegenerative disease that leads to the death of motor and cortical neurons. The clinical manifestations of ALS are heterogenous, and efficacious treatments to significantly slow the progression of the disease are lacking. Cortical hyper-excitability is observed pre-symptomatically across disease-causative genetic variants, as well as in the early stages of sporadic ALS, and typically precedes motor neuron involvement and overt neurodegeneration. The causes of cortical hyper-excitability are not yet fully understood but is mainly agreed to be an early event. The identification of the nucleotide repeat expansion (GGGGCC)n in the C9ORF72 gene has provided evidence that ALS and another neurodegenerative disease, frontotemporal dementia (FTD), are part of a disease spectrum with common genetic origins. ALS and FTD are diseases in which synaptic dysfunction is reported throughout disease onset and stages of progression. It has become apparent that ALS/FTD-causative genes, such as C9ORF72, may have roles in maintaining the normal physiology of the synapse, as mutations in these genes often manifest in synaptic dysfunction. Here we review the dysfunctions of the central nervous system synapses associated with the nucleotide repeat expansion in C9ORF72 observed in patients, organismal, and cellular models of ALS and FTD.
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27
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Kaliszewska A, Allison J, Col TT, Shaw C, Arias N. Elucidating the Role of Cerebellar Synaptic Dysfunction in C9orf72-ALS/FTD - a Systematic Review and Meta-Analysis. CEREBELLUM (LONDON, ENGLAND) 2022; 21:681-714. [PMID: 34491551 PMCID: PMC9325807 DOI: 10.1007/s12311-021-01320-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Accepted: 08/16/2021] [Indexed: 12/28/2022]
Abstract
A hexanucleotide repeat expansion in the C9orf72 gene is the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) with synaptic dysfunction identified as an early pathological hallmark. Although TDP-43 pathology and overt neurodegeneration are largely absent from the cerebellum, the pathological hallmarks of RNA foci and dipeptide repeat protein (DPR) inclusions are most abundant. Here, we present a systematic literature search in the databases of PubMed, Scopus, Embase, Web of Science and Science Direct up until March 5, 2021, which yielded 19,515 publications. Following the exclusion criteria, 72 articles were included having referred to C9orf72, synapses and the cerebellum. Meta-analyses were conducted on studies which reported experimental and control groups with means and standard deviations extracted from figures using the online tool PlotDigitizer. This revealed dendritic defects (P = 0.03), reduced C9orf72 in human patients (P = 0.005) and DPR-related neuronal loss (P = 0.0006) but no neuromuscular junction abnormalities (P = 0.29) or cerebellar neuronal loss (P = 0.23). Our results suggest that dendritic arborisation defects, synaptic gene dysregulation and altered synaptic neurotransmission may drive cerebellar synaptic dysfunction in C9-ALS/FTD. In this review, we discuss how the chronological appearance of the different pathological hallmarks alters synaptic integrity which may have profound implications for disease progression. We conclude that a reduction in C9orf72 protein levels combined with the accumulation of RNA foci and DPRs act synergistically to drive C9 synaptopathy in the cerebellum of C9-ALS/FTD patients.
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Affiliation(s)
- Aleksandra Kaliszewska
- UK Dementia Research Institute At King's College London, Institute of Psychiatry, Psychology and Neuroscience, Department of Basic & Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, 5 Cutcombe road, Camberwell, SE59RX, London, UK
| | - Joseph Allison
- UK Dementia Research Institute At King's College London, Institute of Psychiatry, Psychology and Neuroscience, Department of Basic & Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, 5 Cutcombe road, Camberwell, SE59RX, London, UK
| | - Tarik-Tarkan Col
- UK Dementia Research Institute At King's College London, Institute of Psychiatry, Psychology and Neuroscience, Department of Basic & Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, 5 Cutcombe road, Camberwell, SE59RX, London, UK
| | - Christopher Shaw
- UK Dementia Research Institute At King's College London, Institute of Psychiatry, Psychology and Neuroscience, Department of Basic & Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, 5 Cutcombe road, Camberwell, SE59RX, London, UK
- Centre for Brain Research, University of Auckland, 85 Grafton Road, Auckland, 1023, New Zealand
| | - Natalia Arias
- UK Dementia Research Institute At King's College London, Institute of Psychiatry, Psychology and Neuroscience, Department of Basic & Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, 5 Cutcombe road, Camberwell, SE59RX, London, UK.
- INEUROPA, Instituto de Neurociencias del Principado de Asturias, Plaza Feijoo s/n, 33003, Oviedo, Spain.
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28
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Gene Therapy in Amyotrophic Lateral Sclerosis. Cells 2022; 11:cells11132066. [PMID: 35805149 PMCID: PMC9265980 DOI: 10.3390/cells11132066] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 06/24/2022] [Accepted: 06/27/2022] [Indexed: 12/30/2022] Open
Abstract
Since the discovery of Cu/Zn superoxide dismutase (SOD1) gene mutation, in 1993, as the first genetic abnormality in amyotrophic lateral sclerosis (ALS), over 50 genes have been identified as either cause or modifier in ALS and ALS/frontotemporal dementia (FTD) spectrum disease. Mutations in C9orf72, SOD1, TAR DNA binding protein 43 (TARDBP), and fused in sarcoma (FUS) genes are the four most common ones. During the last three decades, tremendous effort has been made worldwide to reveal biological pathways underlying the pathogenesis of these gene mutations in ALS/FTD. Accordingly, targeting etiologic genes (i.e., gene therapies) to suppress their toxic effects have been investigated widely. It includes four major strategies: (i) removal or inhibition of abnormal transcribed RNA using microRNA or antisense oligonucleotides (ASOs), (ii) degradation of abnormal mRNA using RNA interference (RNAi), (iii) decrease or inhibition of mutant proteins (e.g., using antibodies against misfolded proteins), and (iv) DNA genome editing with methods such as clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein (CRISPR/Cas). The promising results of these studies have led to the application of some of these strategies into ALS clinical trials, especially for C9orf72 and SOD1. In this paper, we will overview advances in gene therapy in ALS/FTD, focusing on C9orf72, SOD1, TARDBP, and FUS genes.
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29
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Lambert-Smith IA, Saunders DN, Yerbury JJ. Progress in biophysics and molecular biology proteostasis impairment and ALS. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2022; 174:3-27. [PMID: 35716729 DOI: 10.1016/j.pbiomolbio.2022.06.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 05/19/2022] [Accepted: 06/09/2022] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a rapidly progressive and fatal neurodegenerative disease that results from the loss of both upper and lower motor neurons. It is the most common motor neuron disease and currently has no effective treatment. There is mounting evidence to suggest that disturbances in proteostasis play a significant role in ALS pathogenesis. Proteostasis is the maintenance of the proteome at the right level, conformation and location to allow a cell to perform its intended function. In this review, we present a thorough synthesis of the literature that provides evidence that genetic mutations associated with ALS cause imbalance to a proteome that is vulnerable to such pressure due to its metastable nature. We propose that the mechanism underlying motor neuron death caused by defects in mRNA metabolism and protein degradation pathways converges on proteostasis dysfunction. We propose that the proteostasis network may provide an effective target for therapeutic development in ALS.
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Affiliation(s)
- Isabella A Lambert-Smith
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia; Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Darren N Saunders
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia
| | - Justin J Yerbury
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia; Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia.
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30
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Advanced Gene-Targeting Therapies for Motor Neuron Diseases and Muscular Dystrophies. Int J Mol Sci 2022; 23:ijms23094824. [PMID: 35563214 PMCID: PMC9101723 DOI: 10.3390/ijms23094824] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 04/22/2022] [Accepted: 04/25/2022] [Indexed: 12/19/2022] Open
Abstract
Gene therapy is a revolutionary, cutting-edge approach to permanently ameliorate or amend many neuromuscular diseases by targeting their genetic origins. Motor neuron diseases and muscular dystrophies, whose genetic causes are well known, are the frontiers of this research revolution. Several genetic treatments, with diverse mechanisms of action and delivery methods, have been approved during the past decade and have demonstrated remarkable results. However, despite the high number of genetic treatments studied preclinically, those that have been advanced to clinical trials are significantly fewer. The most clinically advanced treatments include adeno-associated virus gene replacement therapy, antisense oligonucleotides, and RNA interference. This review provides a comprehensive overview of the advanced gene therapies for motor neuron diseases (i.e., amyotrophic lateral sclerosis and spinal muscular atrophy) and muscular dystrophies (i.e., Duchenne muscular dystrophy, limb-girdle muscular dystrophy, and myotonic dystrophy) tested in clinical trials. Emphasis has been placed on those methods that are a few steps away from their authoritative approval.
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D’Anca M, Buccellato FR, Fenoglio C, Galimberti D. Circular RNAs: Emblematic Players of Neurogenesis and Neurodegeneration. Int J Mol Sci 2022; 23:ijms23084134. [PMID: 35456950 PMCID: PMC9032451 DOI: 10.3390/ijms23084134] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 04/06/2022] [Indexed: 12/13/2022] Open
Abstract
In the fascinating landscape of non-coding RNAs (ncRNAs), circular RNAs (circRNAs) are peeping out as a new promising and appreciated class of molecules with great potential as diagnostic and prognostic biomarkers. They come from circularization of single-stranded RNA molecules covalently closed and generated through alternative mRNA splicing. Dismissed for many years, similar to aberrant splicing by-products, nowadays, their role has been regained. They are able to regulate the expression of linear mRNA transcripts at different levels acting as miRNA sponges, interacting with ribonucleoproteins or exerting a control on gene expression. On the other hand, being extremely conserved across phyla and stable, cell and tissue specific, mostly abundant than the linear RNAs, it is not surprising that they should have critical biological functions. Curiously, circRNAs are particularly expressed in brain and they build up during aging and age-related diseases. These extraordinary peculiarities make circRNAs potentially suitable as promising molecular biomarkers, especially of aging and neurodegenerative diseases. This review aims to explore new evidence on circRNAs, emphasizing their role in aging and pathogenesis of major neurodegenerative disorders, Alzheimer's disease, frontotemporal dementia, and Parkinson's diseases with a look toward their potential usefulness in biomarker searching.
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Affiliation(s)
- Marianna D’Anca
- Foundation IRCCS Ca’ Granda, Ospedale Maggiore Policlinico, 20122 Milan, Italy; (F.R.B.); or (C.F.); or (D.G.)
- Correspondence:
| | - Francesca R. Buccellato
- Foundation IRCCS Ca’ Granda, Ospedale Maggiore Policlinico, 20122 Milan, Italy; (F.R.B.); or (C.F.); or (D.G.)
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, 20122 Milan, Italy
| | - Chiara Fenoglio
- Foundation IRCCS Ca’ Granda, Ospedale Maggiore Policlinico, 20122 Milan, Italy; (F.R.B.); or (C.F.); or (D.G.)
- Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy
| | - Daniela Galimberti
- Foundation IRCCS Ca’ Granda, Ospedale Maggiore Policlinico, 20122 Milan, Italy; (F.R.B.); or (C.F.); or (D.G.)
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, 20122 Milan, Italy
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Rigo R, Groaz E, Sissi C. Polymorphic and Higher-Order G-Quadruplexes as Possible Transcription Regulators: Novel Perspectives for Future Anticancer Therapeutic Applications. Pharmaceuticals (Basel) 2022; 15:ph15030373. [PMID: 35337170 PMCID: PMC8950063 DOI: 10.3390/ph15030373] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 03/14/2022] [Accepted: 03/15/2022] [Indexed: 02/06/2023] Open
Abstract
In the past two decades, significant efforts have been put into designing small molecules to target selected genomic sites where DNA conformational rearrangements control gene expression. G-rich sequences at oncogene promoters are considered good points of intervention since, under specific environmental conditions, they can fold into non-canonical tetrahelical structures known as G-quadruplexes. However, emerging evidence points to a frequent lack of correlation between small molecule targeting of G-quadruplexes at gene promoters and the expression of the associated protein, which hampers pharmaceutical applications. The wide genomic localization of G-quadruplexes along with their highly polymorphic behavior may account for this scenario, suggesting the need for more focused drug design strategies. Here, we will summarize the G4 structural features that can be considered to fulfill this goal. In particular, by comparing a telomeric sequence with the well-characterized G-rich domain of the KIT promoter, we will address how multiple secondary structures might cooperate to control genome architecture at a higher level. If this holds true, the link between drug–DNA complex formation and the associated cellular effects will need to be revisited.
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Affiliation(s)
- Riccardo Rigo
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Marzolo 5, 35131 Padova, Italy; (R.R.); (E.G.)
- CEITEC—Central European Institute of Technology, Masaryk University, Kamenice 753/5, 625 00 Brno, Czech Republic
| | - Elisabetta Groaz
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Marzolo 5, 35131 Padova, Italy; (R.R.); (E.G.)
- KU Leuven, Rega Institute for Medical Research, Medicinal Chemistry, Herestraat 49-Box 1041, 3000 Leuven, Belgium
| | - Claudia Sissi
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Marzolo 5, 35131 Padova, Italy; (R.R.); (E.G.)
- Correspondence:
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Masrori P, Beckers J, Gossye H, Van Damme P. The role of inflammation in neurodegeneration: novel insights into the role of the immune system in C9orf72 HRE-mediated ALS/FTD. Mol Neurodegener 2022; 17:22. [PMID: 35303907 PMCID: PMC8932121 DOI: 10.1186/s13024-022-00525-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 02/25/2022] [Indexed: 12/13/2022] Open
Abstract
Neuroinflammation is an important hallmark of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). An inflammatory reaction to neuronal injury is deemed vital for neuronal health and homeostasis. However, a continued activation of the inflammatory response can be detrimental to remaining neurons and aggravate the disease process. Apart from a disease modifying role, some evidence suggests that neuroinflammation may also contribute to the upstream cause of the disease. In this review, we will first focus on the role of neuroinflammation in the pathogenesis of chromosome 9 open reading frame 72 gene (C9orf72) hexanucleotide repeat expansions (HRE)-mediated ALS/FTD (C9-ALS/FTD). Additionally, we will discuss evidence from ex vivo and in vivo studies and finally, we briefly summarize the trials and progress of anti-inflammatory therapies.
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Affiliation(s)
- Pegah Masrori
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute (LBI), KU Leuven-University of Leuven, 3000, Leuven, Belgium.,Laboratory of Neurobiology, Experimental Neurology, Center for Brain and Disease Research, VIB, Campus Gasthuisberg, O&N5, Herestraat 49, 602, 3000, Leuven, PB, Belgium.,Neurology Department, University Hospitals Leuven, Campus Gasthuisberg, Herestraat 49, 3000, Leuven, Belgium.,Department of Neurology, University Hospital Antwerp, 2650, Edegem, Belgium
| | - Jimmy Beckers
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute (LBI), KU Leuven-University of Leuven, 3000, Leuven, Belgium.,Laboratory of Neurobiology, Experimental Neurology, Center for Brain and Disease Research, VIB, Campus Gasthuisberg, O&N5, Herestraat 49, 602, 3000, Leuven, PB, Belgium
| | - Helena Gossye
- Department of Neurology, University Hospital Antwerp, 2650, Edegem, Belgium.,VIB Center for Molecular Neurology, Neurodegenerative Brain Diseases, University of Antwerp, 2000, Antwerp, Belgium.,Department of Biomedical Sciences, University of Antwerp, 2000, Antwerp, Belgium
| | - Philip Van Damme
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute (LBI), KU Leuven-University of Leuven, 3000, Leuven, Belgium. .,Laboratory of Neurobiology, Experimental Neurology, Center for Brain and Disease Research, VIB, Campus Gasthuisberg, O&N5, Herestraat 49, 602, 3000, Leuven, PB, Belgium. .,Neurology Department, University Hospitals Leuven, Campus Gasthuisberg, Herestraat 49, 3000, Leuven, Belgium.
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Jiang L, Zhang T, Lu K, Qi S. The progress in C9orf72 research: ALS/FTD pathogenesis, functions and structure. Small GTPases 2022; 13:56-76. [PMID: 33663328 PMCID: PMC9707547 DOI: 10.1080/21541248.2021.1892443] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The hexanucleotide repeat (GGGGCC) expansion in C9orf72 is accounted for a large proportion of the genetic amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). The hypotheses of how the massive G4C2 repeats in C9orf72 destroy the neurons and lead to ALS/FTD are raised and improving. As a multirole player, C9orf72 exerts critical roles in many cellular processes, including autophagy, membrane trafficking, immune response, and so on. Notably, the partners of C9orf72, through which C9orf72 participates in the cell activities, have been identified. Notably, the structures of the C9orf72-SMCR8-WDR41 complex shed light on its activity as GTPase activating proteins (GAP). In this manuscript, we reviewed the latest research progress in the C9orf72-mediated ALS/FTD, the physiological functions of C9orf72, and the putative function models of C9orf72/C9orf72-containing complex.
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Affiliation(s)
- Lan Jiang
- Department of Urology, State Key Laboratory of Biotherapy, West China Hospital, College of Life Sciences, Sichuan University, Chengdu, China
| | - Tizhong Zhang
- Department of Urology, State Key Laboratory of Biotherapy, West China Hospital, College of Life Sciences, Sichuan University, Chengdu, China
| | - Kefeng Lu
- Department of Urology, State Key Laboratory of Biotherapy, West China Hospital, College of Life Sciences, Sichuan University, Chengdu, China
| | - Shiqian Qi
- Department of Urology, State Key Laboratory of Biotherapy, West China Hospital, College of Life Sciences, Sichuan University, Chengdu, China,CONTACT Shiqian Qi Department of Urology, State Key Laboratory of Biotherapy, West China Hospital, College of Life Sciences, Sichuan University, Chengdu, China.
These authors contributed equally to this work.
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Ozcan KA, Ghaffari LT, Haeusler AR. The effects of molecular crowding and CpG hypermethylation on DNA G-quadruplexes formed by the C9orf72 nucleotide repeat expansion. Sci Rep 2021; 11:23213. [PMID: 34853325 PMCID: PMC8636472 DOI: 10.1038/s41598-021-02041-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 11/09/2021] [Indexed: 01/09/2023] Open
Abstract
A nucleotide repeat expansion (NRE), (G4C2)n, located in a classically noncoding region of C9orf72 (C9), is the most common genetic mutation associated with ALS/FTD. There is increasing evidence that nucleic acid structures formed by the C9-NRE may both contribute to ALS/FTD, and serve as therapeutic targets, but there is limited characterization of these nucleic acid structures under physiologically and disease relevant conditions. Here we show in vitro that the C9-NRE DNA can form both parallel and antiparallel DNA G-quadruplex (GQ) topological structures and that the structural preference of these DNA GQs can be dependent on the molecular crowding conditions. Additionally, 5-methylcytosine DNA hypermethylation, which is observed in the C9-NRE locus in some patients, has minimal effects on GQ topological preferences. Finally, molecular dynamic simulations of methylated and nonmethylated GQ structures support in vitro data showing that DNA GQ structures formed by the C9-NRE DNA are stable, with structural fluctuations limited to the cytosine-containing loop regions. These findings provide new insight into the structural polymorphic preferences and stability of DNA GQs formed by the C9-NRE in both the methylated and nonmethylated states, as well as reveal important features to guide the development of upstream therapeutic approaches to potentially attenuate C9-NRE-linked diseases.
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Affiliation(s)
- Kadir A Ozcan
- Department of Neuroscience, Jefferson Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA
| | - Layla T Ghaffari
- Department of Neuroscience, Jefferson Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA
| | - Aaron R Haeusler
- Department of Neuroscience, Jefferson Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA. .,Department of Neuroscience, Jefferson Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Thomas Jefferson University, 900 Walnut Street, JHN suite 410, Philadelphia, PA, 19107, USA.
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36
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Gerou M, Hall B, Woof R, Allsop J, Kolb SJ, Meyer K, Shaw PJ, Allen SP. Amyotrophic lateral sclerosis alters the metabolic aging profile in patient derived fibroblasts. Neurobiol Aging 2021; 105:64-77. [PMID: 34044197 PMCID: PMC8346650 DOI: 10.1016/j.neurobiolaging.2021.04.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 04/18/2021] [Accepted: 04/20/2021] [Indexed: 12/19/2022]
Abstract
Aging is a major risk factor for neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS). As metabolic alterations are a hallmark of aging and have previously been observed in ALS, it is important to examine the effect of aging in the context of ALS metabolic function. Here, using a newly established phenotypic metabolic approach, we examined the effect of aging on the metabolic profile of fibroblasts derived from ALS cases compared to controls. We found that ALS fibroblasts have an altered metabolic profile, which is influenced by age. In control cases, we found significant increases with age in NADH metabolism in the presence of several metabolites including lactic acid, trehalose, uridine and fructose, which was not recapitulated in ALS cases. Conversely, we found a reduction of NADH metabolism with age of biopsy, age of onset and age of death in the presence of glycogen in the ALS cohort. Furthermore, we found that NADH production correlated with disease progression rates in relation to a number of metabolites including inosine and α-ketoglutaric acid. Inosine or α-ketoglutaric acid supplementation in ALS fibroblasts was bioenergetically favourable. Overall, we found aging related defects in energy substrates that feed carbon into glycolysis at various points as well as the tricarboxylic acid (TCA) cycle in ALS fibroblasts, which was validated in induced neuronal progenitor cell derived iAstrocytes. Our results suggest that supplementing those pathways may protect against age related metabolic dysfunction in ALS.
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Affiliation(s)
- Margarita Gerou
- Department of Neuroscience, Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, UK
| | - Benjamin Hall
- Department of Neuroscience, Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, UK
| | - Ryan Woof
- Department of Neuroscience, Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, UK
| | - Jessica Allsop
- Department of Neuroscience, Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, UK
| | - Stephen J Kolb
- Department of Neurology, The Ohio State University Wexner Medical Centre, Columbus, OH, USA
| | - Kathrin Meyer
- Centre for Gene Therapy, Nationwide Children's Hospital, Columbus, OH, USA
| | - Pamela J Shaw
- Department of Neuroscience, Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, UK
| | - Scott P Allen
- Department of Neuroscience, Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, UK.
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37
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Nuclear export and translation of circular repeat-containing intronic RNA in C9ORF72-ALS/FTD. Nat Commun 2021; 12:4908. [PMID: 34389711 PMCID: PMC8363653 DOI: 10.1038/s41467-021-25082-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Accepted: 07/16/2021] [Indexed: 12/14/2022] Open
Abstract
C9ORF72 hexanucleotide GGGGCC repeat expansion is the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Repeat-containing RNA mediates toxicity through nuclear granules and dipeptide repeat (DPR) proteins produced by repeat-associated non-AUG translation. However, it remains unclear how the intron-localized repeats are exported and translated in the cytoplasm. We use single molecule imaging approach to examine the molecular identity and spatiotemporal dynamics of the repeat RNA. We demonstrate that the spliced intron with G-rich repeats is stabilized in a circular form due to defective lariat debranching. The spliced circular intron, instead of pre-mRNA, serves as the translation template. The NXF1-NXT1 pathway plays an important role in the nuclear export of the circular intron and modulates toxic DPR production. This study reveals an uncharacterized disease-causing RNA species mediated by repeat expansion and demonstrates the importance of RNA spatial localization to understand disease etiology. Hexanucleotide repeat expansion in the intron 1 of the C9ORF72 gene can cause amyotrophic lateral sclerosis (ALS) and frontal temporal dementia (FTD). Here the authors use single molecule imaging to show nuclear export and translation of circular repeat-containing C9ORF72 intronic RNA.
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38
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C9orf72-G 4C 2 Intermediate Repeats and Parkinson's Disease; A Data-Driven Hypothesis. Genes (Basel) 2021; 12:genes12081210. [PMID: 34440384 PMCID: PMC8391122 DOI: 10.3390/genes12081210] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 08/02/2021] [Accepted: 08/03/2021] [Indexed: 11/30/2022] Open
Abstract
Pathogenic C9orf72-G4C2 repeat expansions are associated with ALS/FTD, but not with Parkinson’s disease (PD); yet the possible link between intermediate repeat lengths and PD remains inconclusive. We aim to study the potential involvement of these repeats in PD. The number of C9orf72-repeats were determined by flanking and repeat-primed PCR assays, and the risk-haplotype was determined by SNP-array. Their association with PD was assessed in a stratified manner: in PD-patients-carriers of mutations in LRRK2, GBA, or SMPD1 genes (n = 388), and in PD-non-carriers (NC, n = 718). Allelic distribution was significantly different only in PD-NC compared to 600 controls when looking both at the allele with higher repeat’s size (p = 0.034) and at the combined number of repeats from both alleles (p = 0.023). Intermediate repeats (20–60 repeats) were associated with PD in PD-NC patients (p = 0.041; OR = 3.684 (CI 1.05–13.0)) but not in PD-carriers (p = 0.684). The C9orf72 risk-haplotype, determined in a subgroup of 588 PDs and 126 controls, was observed in higher frequency in PD-NC (dominant model, OR = 1.71, CI 1.04–2.81, p = 0.0356). All 19 alleles within the risk-haplotype were associated with higher C9orf72 RNA levels according to the GTEx database. Based on our data, we suggest a model in which intermediate repeats are a risk factor for PD in non-carriers, driven not only by the number of repeats but also by the variants’ genotypes within the risk-haplotype. Further studies are needed to elucidate this possible role of C9orf72 in PD pathogenesis.
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Thibault PA, Ganesan A, Kalyaanamoorthy S, Clarke JPWE, Salapa HE, Levin MC. hnRNP A/B Proteins: An Encyclopedic Assessment of Their Roles in Homeostasis and Disease. BIOLOGY 2021; 10:biology10080712. [PMID: 34439945 PMCID: PMC8389229 DOI: 10.3390/biology10080712] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/16/2021] [Accepted: 07/21/2021] [Indexed: 12/13/2022]
Abstract
The hnRNP A/B family of proteins is canonically central to cellular RNA metabolism, but due to their highly conserved nature, the functional differences between hnRNP A1, A2/B1, A0, and A3 are often overlooked. In this review, we explore and identify the shared and disparate homeostatic and disease-related functions of the hnRNP A/B family proteins, highlighting areas where the proteins have not been clearly differentiated. Herein, we provide a comprehensive assembly of the literature on these proteins. We find that there are critical gaps in our grasp of A/B proteins' alternative splice isoforms, structures, regulation, and tissue and cell-type-specific functions, and propose that future mechanistic research integrating multiple A/B proteins will significantly improve our understanding of how this essential protein family contributes to cell homeostasis and disease.
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Affiliation(s)
- Patricia A. Thibault
- Office of the Saskatchewan Multiple Sclerosis Clinical Research Chair, University of Saskatchewan, Saskatoon, SK S7K 0M7, Canada; (P.A.T.); (J.-P.W.E.C.); (H.E.S.)
- Department of Medicine, Neurology Division, University of Saskatchewan, Saskatoon, SK S7N 0X8, Canada
| | - Aravindhan Ganesan
- ArGan’s Lab, School of Pharmacy, Faculty of Science, University of Waterloo, Waterloo, ON N2L 3G1, Canada;
| | - Subha Kalyaanamoorthy
- Department of Chemistry, Faculty of Science, University of Waterloo, Waterloo, ON N2L 3G1, Canada;
| | - Joseph-Patrick W. E. Clarke
- Office of the Saskatchewan Multiple Sclerosis Clinical Research Chair, University of Saskatchewan, Saskatoon, SK S7K 0M7, Canada; (P.A.T.); (J.-P.W.E.C.); (H.E.S.)
- Department of Health Sciences, College of Medicine, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
- Department of Anatomy, Physiology and Pharmacology, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
| | - Hannah E. Salapa
- Office of the Saskatchewan Multiple Sclerosis Clinical Research Chair, University of Saskatchewan, Saskatoon, SK S7K 0M7, Canada; (P.A.T.); (J.-P.W.E.C.); (H.E.S.)
- Department of Medicine, Neurology Division, University of Saskatchewan, Saskatoon, SK S7N 0X8, Canada
| | - Michael C. Levin
- Office of the Saskatchewan Multiple Sclerosis Clinical Research Chair, University of Saskatchewan, Saskatoon, SK S7K 0M7, Canada; (P.A.T.); (J.-P.W.E.C.); (H.E.S.)
- Department of Medicine, Neurology Division, University of Saskatchewan, Saskatoon, SK S7N 0X8, Canada
- Department of Health Sciences, College of Medicine, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
- Department of Anatomy, Physiology and Pharmacology, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
- Correspondence:
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Nanoscopic investigation of C9orf72 poly-GA oligomers on nuclear membrane disruption by a photoinducible platform. Commun Chem 2021; 4:111. [PMID: 36697556 PMCID: PMC9814621 DOI: 10.1038/s42004-021-00547-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 07/01/2021] [Indexed: 01/28/2023] Open
Abstract
Glycine-alanine dipeptide repeats (GA DPRs) translated from the mutated C9orf72 gene have recently been correlated with amyotrophic lateral sclerosis (ALS). While GA DPRs aggregates have been suggested as amyloid, the biophysical features and cytotoxicity of GA DPRs oligomers has not been explored due to its unstable nature. In this study, we develop a photoinducible platform based on methoxynitrobenzene chemistry to enrich GA DPRs that allows monitoring the oligomerization process of GA DPRs in cells. By applying advanced microscopies, we examined the GA DPRs oligomerization process nanoscopically in a time-dependent manner. We provided direct evidences to demonstrate GA DPRs oligomers rather than nanofibrils disrupt nuclear membrane. Moreover, we found GA DPRs hamper nucleocytoplasmic transport in cells and cause cytosolic retention of TAR DNA-binding protein 43 in cortical neurons. Our results highlight the toxicity of GA DPRs oligomers, which is a key step toward elucidating the pathological roles of C9orf72 DPRs.
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41
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Liu X, Xiong Y, Zhang C, Lai R, Liu H, Peng R, Fu T, Liu Q, Fang X, Mann S, Tan W. G-Quadruplex-Induced Liquid-Liquid Phase Separation in Biomimetic Protocells. J Am Chem Soc 2021; 143:11036-11043. [PMID: 34270902 DOI: 10.1021/jacs.1c03627] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Biomolecular condensates comprised of specific proteins and nucleic acids are now recognized as one of the key organizing mechanisms in eukaryotic cells. However, the specific roles played by the nucleic acid secondary structure and sequence in biomolecular phase separation are still not clear. Here, utilizing giant membrane vesicles (GMVs) as a protocell model, we found that single-stranded DNA (ssDNA) with a parallel G-quadruplex structure could functionally cooperate with a G-quadruplex-binding protein to form speckle-like puncta inside the GMVs. The clustering behavior is dependent on the structural diversity of G-quadruplexes, and the reversible clustering behavior implicated a new pathway in dynamically regulating the formation of biomolecular condensates. This finding represents a potential link between G-quadruplex-binding proteins and the resulting G-quadruplex-mediated biomolecular phase separation, which would gain insight into a wide range of biological processes associated with nucleic acid-modulated phase separation inside living cells.
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Affiliation(s)
- Xuejiao Liu
- Molecular Science and Biomedicine Laboratory (MBL), State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, College of Chemistry and Chemical Engineering, Aptamer Engineering Center of Hunan Province, Hunan University, Changsha, Hunan 410082, China
| | - Yansong Xiong
- Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Chunjuan Zhang
- Molecular Science and Biomedicine Laboratory (MBL), State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, College of Chemistry and Chemical Engineering, Aptamer Engineering Center of Hunan Province, Hunan University, Changsha, Hunan 410082, China
| | - Rongji Lai
- Molecular Science and Biomedicine Laboratory (MBL), State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, College of Chemistry and Chemical Engineering, Aptamer Engineering Center of Hunan Province, Hunan University, Changsha, Hunan 410082, China
| | - Hui Liu
- Molecular Science and Biomedicine Laboratory (MBL), State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, College of Chemistry and Chemical Engineering, Aptamer Engineering Center of Hunan Province, Hunan University, Changsha, Hunan 410082, China
| | - Ruizi Peng
- Molecular Science and Biomedicine Laboratory (MBL), State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, College of Chemistry and Chemical Engineering, Aptamer Engineering Center of Hunan Province, Hunan University, Changsha, Hunan 410082, China.,The Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer Hospital), Institute of Basic Medicine and Cancer (IBMC), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, China
| | - Ting Fu
- The Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer Hospital), Institute of Basic Medicine and Cancer (IBMC), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, China
| | - Qiaoling Liu
- Molecular Science and Biomedicine Laboratory (MBL), State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, College of Chemistry and Chemical Engineering, Aptamer Engineering Center of Hunan Province, Hunan University, Changsha, Hunan 410082, China
| | - Xiaohong Fang
- Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.,The Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer Hospital), Institute of Basic Medicine and Cancer (IBMC), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, China
| | - Stephen Mann
- Centre for Protolife Research and Centre for Organized Matter Chemistry, School of Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom.,Max Planck-Bristol Centre for Minimal Biology, School of Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom.,School of Materials Science and Engineering, Institute of Molecular Medicine (IMM), Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Weihong Tan
- Molecular Science and Biomedicine Laboratory (MBL), State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, College of Chemistry and Chemical Engineering, Aptamer Engineering Center of Hunan Province, Hunan University, Changsha, Hunan 410082, China.,The Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer Hospital), Institute of Basic Medicine and Cancer (IBMC), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, China.,School of Materials Science and Engineering, Institute of Molecular Medicine (IMM), Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Jiao Tong University, Shanghai 200240, China
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Root J, Merino P, Nuckols A, Johnson M, Kukar T. Lysosome dysfunction as a cause of neurodegenerative diseases: Lessons from frontotemporal dementia and amyotrophic lateral sclerosis. Neurobiol Dis 2021; 154:105360. [PMID: 33812000 PMCID: PMC8113138 DOI: 10.1016/j.nbd.2021.105360] [Citation(s) in RCA: 91] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 03/16/2021] [Accepted: 03/29/2021] [Indexed: 12/11/2022] Open
Abstract
Frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) are fatal neurodegenerative disorders that are thought to exist on a clinical and pathological spectrum. FTD and ALS are linked by shared genetic causes (e.g. C9orf72 hexanucleotide repeat expansions) and neuropathology, such as inclusions of ubiquitinated, misfolded proteins (e.g. TAR DNA-binding protein 43; TDP-43) in the CNS. Furthermore, some genes that cause FTD or ALS when mutated encode proteins that localize to the lysosome or modulate endosome-lysosome function, including lysosomal fusion, cargo trafficking, lysosomal acidification, autophagy, or TFEB activity. In this review, we summarize evidence that lysosomal dysfunction, caused by genetic mutations (e.g. C9orf72, GRN, MAPT, TMEM106B) or toxic-gain of function (e.g. aggregation of TDP-43 or tau), is an important pathogenic disease mechanism in FTD and ALS. Further studies into the normal function of many of these proteins are required and will help uncover the mechanisms that cause lysosomal dysfunction in FTD and ALS. Mutations or polymorphisms in genes that encode proteins important for endosome-lysosome function also occur in other age-dependent neurodegenerative diseases, including Alzheimer's (e.g. APOE, PSEN1, APP) and Parkinson's (e.g. GBA, LRRK2, ATP13A2) disease. A more complete understanding of the common and unique features of lysosome dysfunction across the spectrum of neurodegeneration will help guide the development of therapies for these devastating diseases.
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Affiliation(s)
- Jessica Root
- Department of Pharmacology and Chemical Biology, Emory University, School of Medicine, Atlanta 30322, Georgia; Center for Neurodegenerative Disease, Emory University, School of Medicine, Atlanta 30322, Georgia
| | - Paola Merino
- Department of Pharmacology and Chemical Biology, Emory University, School of Medicine, Atlanta 30322, Georgia; Center for Neurodegenerative Disease, Emory University, School of Medicine, Atlanta 30322, Georgia
| | - Austin Nuckols
- Department of Pharmacology and Chemical Biology, Emory University, School of Medicine, Atlanta 30322, Georgia; Center for Neurodegenerative Disease, Emory University, School of Medicine, Atlanta 30322, Georgia
| | - Michelle Johnson
- Department of Pharmacology and Chemical Biology, Emory University, School of Medicine, Atlanta 30322, Georgia; Center for Neurodegenerative Disease, Emory University, School of Medicine, Atlanta 30322, Georgia
| | - Thomas Kukar
- Department of Pharmacology and Chemical Biology, Emory University, School of Medicine, Atlanta 30322, Georgia; Center for Neurodegenerative Disease, Emory University, School of Medicine, Atlanta 30322, Georgia; Department of Neurology, Emory University, School of Medicine, Atlanta 30322, Georgia.
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Nishimura AL, Arias N. Synaptopathy Mechanisms in ALS Caused by C9orf72 Repeat Expansion. Front Cell Neurosci 2021; 15:660693. [PMID: 34140881 PMCID: PMC8203826 DOI: 10.3389/fncel.2021.660693] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 05/03/2021] [Indexed: 12/14/2022] Open
Abstract
Amyotrophic Lateral Sclerosis (ALS) is a complex neurodegenerative disease caused by degeneration of motor neurons (MNs). ALS pathogenic features include accumulation of misfolded proteins, glutamate excitotoxicity, mitochondrial dysfunction at distal axon terminals, and neuronal cytoskeleton changes. Synergies between loss of C9orf72 functions and gain of function by toxic effects of repeat expansions also contribute to C9orf72-mediated pathogenesis. However, the impact of haploinsufficiency of C9orf72 on neurons and in synaptic functions requires further examination. As the motor neurons degenerate, the disease symptoms will lead to neurotransmission deficiencies in the brain, spinal cord, and neuromuscular junction. Altered neuronal excitability, synaptic morphological changes, and C9orf72 protein and DPR localization at the synapses, suggest a potential involvement of C9orf72 at synapses. In this review article, we provide a conceptual framework for assessing the putative involvement of C9orf72 as a synaptopathy, and we explore the underlying and common disease mechanisms with other neurodegenerative diseases. Finally, we reflect on the major challenges of understanding C9orf72-ALS as a synaptopathy focusing on integrating mitochondrial and neuronal cytoskeleton degeneration as biomarkers and potential targets to treat ALS neurodegeneration.
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Affiliation(s)
- Agnes L Nishimura
- Department of Basic and Clinical Neuroscience, UK Dementia Research Institute, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Natalia Arias
- Department of Basic and Clinical Neuroscience, UK Dementia Research Institute, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.,INEUROPA, Instituto de Neurociencias del Principado de Asturias, Oviedo, Spain
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Disease Mechanisms and Therapeutic Approaches in C9orf72 ALS-FTD. Biomedicines 2021; 9:biomedicines9060601. [PMID: 34070550 PMCID: PMC8229688 DOI: 10.3390/biomedicines9060601] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/19/2021] [Accepted: 05/20/2021] [Indexed: 01/15/2023] Open
Abstract
A hexanucleotide repeat expansion mutation in the first intron of C9orf72 is the most common known genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia. Since the discovery in 2011, numerous pathogenic mechanisms, including both loss and gain of function, have been proposed. The body of work overall suggests that toxic gain of function arising from bidirectionally transcribed repeat RNA is likely to be the primary driver of disease. In this review, we outline the key pathogenic mechanisms that have been proposed to date and discuss some of the novel therapeutic approaches currently in development.
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UBQLN2-HSP70 axis reduces poly-Gly-Ala aggregates and alleviates behavioral defects in the C9ORF72 animal model. Neuron 2021; 109:1949-1962.e6. [PMID: 33991504 DOI: 10.1016/j.neuron.2021.04.023] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 01/09/2021] [Accepted: 04/23/2021] [Indexed: 12/12/2022]
Abstract
Expansion of a hexanucleotide repeat GGGGCC (G4C2) in the intron of the C9ORF72 gene is the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) (C9-ALS/FTD). Transcripts carrying G4C2 repeat expansions generate neurotoxic dipeptide repeat (DPR) proteins, including poly-Gly-Ala (poly-GA), which tends to form protein aggregates. Here, we demonstrate that UBQLN2, another ALS/FTD risk factor, is recruited to reduce poly-GA aggregates and alleviate poly-GA-induced neurotoxicity. UBQLN2 could recognize HSP70 ubiquitination, which facilitates the UBQLN2-HSP70-GA complex formation and promotes poly-GA degradation. ALS/FTD-related UBQLN2 mutants fail to bind HSP70 and clear poly-GA aggregates. Disruption of the interaction between UBQLN2 and HSP70 inhibits poly-GA aggregation in C9-ALS/FTD iPSC-derived neurons. Finally, enhancing HSP70 by the chemical compound 17AAG at the adult stage mitigates behavioral defects in poly-GA animals. Our findings suggest a critical role of the UBQLN2-HSP70 axis in protein aggregate clearance in C9-ALS/FTD.
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Cave JW, Willis DE. G-quadruplex regulation of neural gene expression. FEBS J 2021; 289:3284-3303. [PMID: 33905176 DOI: 10.1111/febs.15900] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 03/24/2021] [Accepted: 04/23/2021] [Indexed: 12/11/2022]
Abstract
G-quadruplexes are four-stranded helical nucleic acid structures characterized by stacked tetrads of guanosine bases. These structures are widespread throughout mammalian genomic DNA and RNA transcriptomes, and prevalent across all tissues. The role of G-quadruplexes in cancer is well-established, but there has been a growing exploration of these structures in the development and homeostasis of normal tissue. In this review, we focus on the roles of G-quadruplexes in directing gene expression in the nervous system, including the regulation of gene transcription, mRNA processing, and trafficking, as well as protein translation. The role of G-quadruplexes and their molecular interactions in the pathology of neurological diseases is also examined. Outside of cancer, there has been only limited exploration of G-quadruplexes as potential intervention targets to treat disease or injury. We discuss studies that have used small-molecule ligands to manipulate G-quadruplex stability in order to treat disease or direct neural stem/progenitor cell proliferation and differentiation into therapeutically relevant cell types. Understanding the many roles that G-quadruplexes have in the nervous system not only provides critical insight into fundamental molecular mechanisms that control neurological function, but also provides opportunities to identify novel therapeutic targets to treat injury and disease.
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Affiliation(s)
- John W Cave
- InVitro Cell Research LLC, Englewood, NJ, USA
| | - Dianna E Willis
- Burke Neurological Institute, White Plains, NY, USA.,Feil Family Brain & Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
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Paul S, Dansithong W, Figueroa KP, Gandelman M, Scoles DR, Pulst SM. Staufen1 in Human Neurodegeneration. Ann Neurol 2021; 89:1114-1128. [PMID: 33745139 DOI: 10.1002/ana.26069] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 02/10/2021] [Accepted: 03/14/2021] [Indexed: 12/13/2022]
Abstract
OBJECTIVE Mutations in the ATXN2 gene (CAG expansions ≥32 repeats) can be a rare cause of Parkinson's disease and amyotrophic lateral sclerosis (ALS). We recently reported that the stress granule (SG) protein Staufen1 (STAU1) was overabundant in neurodegenerative disorder spinocerebellar ataxia type 2 (SCA2) patient cells, animal models, and ALS-TDP-43 fibroblasts, and provided a link between SG formation and autophagy. We aimed to test if STAU1 overabundance has a role in the pathogenesis of other neurodegenerative diseases. METHODS With multiple neurodegenerative patient-derived cell models, animal models, and human postmortem ALS tissue, we evaluate STAU1 function using biochemical and immunohistological analyses. RESULTS We demonstrate STAU1 overabundance and increased total and phosphorylated mammalian target of rapamycin (mTOR) in fibroblast cells from patients with ALS with mutations in TDP-43, patients with dementia with PSEN1 mutations, a patient with parkinsonism with MAPT mutation, Huntington's disease (HD) mutations, and SCA2 mutations. Increased STAU1 levels and mTOR activity were seen in human ALS spinal cord tissues as well as in animal models. Changes in STAU1 and mTOR protein levels were post-transcriptional. Exogenous expression of STAU1 in wildtype cells was sufficient to activate mTOR and downstream targets and form SGs. Targeting STAU1 by RNAi normalized mTOR, suggesting a potential role for therapy in diseases associated with STAU1 overabundance. INTERPRETATION STAU1 overabundance in neurodegeneration is a common phenomenon associated with hyperactive mTOR. Targeting STAU1 with ASOs or miRNA viral vectors may represent a novel, efficacious therapy for neurodegenerative diseases characterized by overabundant STAU1. ANN NEUROL 2021;89:1114-1128.
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Affiliation(s)
- Sharan Paul
- Department of Neurology, University of Utah, Salt Lake City, UT
| | | | | | - Mandi Gandelman
- Department of Neurology, University of Utah, Salt Lake City, UT
| | - Daniel R Scoles
- Department of Neurology, University of Utah, Salt Lake City, UT
| | - Stefan M Pulst
- Department of Neurology, University of Utah, Salt Lake City, UT
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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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Role of Oxidative Stress in the Pathogenesis of Amyotrophic Lateral Sclerosis: Antioxidant Metalloenzymes and Therapeutic Strategies. Biomolecules 2021; 11:biom11030437. [PMID: 33809730 PMCID: PMC8002298 DOI: 10.3390/biom11030437] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 03/12/2021] [Accepted: 03/12/2021] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) affects motor neurons in the cerebral cortex, brainstem and spinal cord and leads to death due to respiratory failure within three to five years. Although the clinical symptoms of this disease were first described in 1869 and it is the most common motor neuron disease and the most common neurodegenerative disease in middle-aged individuals, the exact etiopathogenesis of ALS remains unclear and it remains incurable. However, free oxygen radicals (i.e., molecules containing one or more free electrons) are known to contribute to the pathogenesis of this disease as they very readily bind intracellular structures, leading to functional impairment. Antioxidant enzymes, which are often metalloenzymes, inactivate free oxygen radicals by converting them into a less harmful substance. One of the most important antioxidant enzymes is Cu2+Zn2+ superoxide dismutase (SOD1), which is mutated in 20% of cases of the familial form of ALS (fALS) and up to 7% of sporadic ALS (sALS) cases. In addition, the proper functioning of catalase and glutathione peroxidase (GPx) is essential for antioxidant protection. In this review article, we focus on the mechanisms through which these enzymes are involved in the antioxidant response to oxidative stress and thus the pathogenesis of ALS and their potential as therapeutic targets.
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Molitor L, Bacher S, Burczyk S, Niessing D. The Molecular Function of PURA and Its Implications in Neurological Diseases. Front Genet 2021; 12:638217. [PMID: 33777106 PMCID: PMC7990775 DOI: 10.3389/fgene.2021.638217] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 02/09/2021] [Indexed: 12/19/2022] Open
Abstract
In recent years, genome-wide analyses of patients have resulted in the identification of a number of neurodevelopmental disorders. Several of them are caused by mutations in genes that encode for RNA-binding proteins. One of these genes is PURA, for which in 2014 mutations have been shown to cause the neurodevelopmental disorder PURA syndrome. Besides intellectual disability (ID), patients develop a variety of symptoms, including hypotonia, metabolic abnormalities as well as epileptic seizures. This review aims to provide a comprehensive assessment of research of the last 30 years on PURA and its recently discovered involvement in neuropathological abnormalities. Being a DNA- and RNA-binding protein, PURA has been implicated in transcriptional control as well as in cytoplasmic RNA localization. Molecular interactions are described and rated according to their validation state as physiological targets. This information will be put into perspective with available structural and biophysical insights on PURA’s molecular functions. Two different knock-out mouse models have been reported with partially contradicting observations. They are compared and put into context with cell biological observations and patient-derived information. In addition to PURA syndrome, the PURA protein has been found in pathological, RNA-containing foci of patients with the RNA-repeat expansion diseases such as fragile X-associated tremor ataxia syndrome (FXTAS) and amyotrophic lateral sclerosis (ALS)/fronto-temporal dementia (FTD) spectrum disorder. We discuss the potential role of PURA in these neurodegenerative disorders and existing evidence that PURA might act as a neuroprotective factor. In summary, this review aims at informing researchers as well as clinicians on our current knowledge of PURA’s molecular and cellular functions as well as its implications in very different neuronal disorders.
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Affiliation(s)
- Lena Molitor
- Institute of Structural Biology, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany
| | - Sabrina Bacher
- Institute of Structural Biology, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany
| | - Sandra Burczyk
- Institute of Pharmaceutical Biotechnology, Ulm University, Ulm, Germany
| | - Dierk Niessing
- Institute of Structural Biology, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany.,Institute of Pharmaceutical Biotechnology, Ulm University, Ulm, Germany
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