1
|
Tseng YJ, Krans A, Malik I, Deng X, Yildirim E, Ovunc S, Tank EH, Jansen-West K, Kaufhold R, Gomez N, Sher R, Petrucelli L, Barmada S, Todd P. Ribosomal quality control factors inhibit repeat-associated non-AUG translation from GC-rich repeats. Nucleic Acids Res 2024; 52:5928-5949. [PMID: 38412259 PMCID: PMC11162809 DOI: 10.1093/nar/gkae137] [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: 06/07/2023] [Revised: 02/05/2024] [Accepted: 02/19/2024] [Indexed: 02/29/2024] Open
Abstract
A GGGGCC (G4C2) hexanucleotide repeat expansion in C9ORF72 causes amyotrophic lateral sclerosis and frontotemporal dementia (C9ALS/FTD), while a CGG trinucleotide repeat expansion in FMR1 leads to the neurodegenerative disorder Fragile X-associated tremor/ataxia syndrome (FXTAS). These GC-rich repeats form RNA secondary structures that support repeat-associated non-AUG (RAN) translation of toxic proteins that contribute to disease pathogenesis. Here we assessed whether these same repeats might trigger stalling and interfere with translational elongation. We find that depletion of ribosome-associated quality control (RQC) factors NEMF, LTN1 and ANKZF1 markedly boost RAN translation product accumulation from both G4C2 and CGG repeats while overexpression of these factors reduces RAN production in both reporter assays and C9ALS/FTD patient iPSC-derived neurons. We also detected partially made products from both G4C2 and CGG repeats whose abundance increased with RQC factor depletion. Repeat RNA sequence, rather than amino acid content, is central to the impact of RQC factor depletion on RAN translation-suggesting a role for RNA secondary structure in these processes. Together, these findings suggest that ribosomal stalling and RQC pathway activation during RAN translation inhibits the generation of toxic RAN products. We propose augmenting RQC activity as a therapeutic strategy in GC-rich repeat expansion disorders.
Collapse
Affiliation(s)
- Yi-Ju Tseng
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
- Cellular and Molecular Biology Graduate Program, University of Michigan, Ann Arbor, MI 48109, USA
| | - Amy Krans
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
- Ann Arbor Veterans Administration Healthcare, Ann Arbor, MI 48109, USA
| | - Indranil Malik
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, Sangareddy, 502284 Telangana, India
| | - Xiexiong Deng
- Department of Molecular, Cellular and Developmental Biology, Howard Hughes Medical Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Evrim Yildirim
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Sinem Ovunc
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Elizabeth M H Tank
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Karen Jansen-West
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Ross Kaufhold
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
- Medical Scientist Training Program, University of Michigan, Ann Arbor, MI 48109, USA
| | - Nicolas B Gomez
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
- Medical Scientist Training Program, University of Michigan, Ann Arbor, MI 48109, USA
| | - Roger Sher
- Department of Neurobiology and Behavior & Center for Nervous System Disorders, Stony Brook University, Stony Brook, NY 11794, USA
| | | | - Sami J Barmada
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Peter K Todd
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
- Ann Arbor Veterans Administration Healthcare, Ann Arbor, MI 48109, USA
| |
Collapse
|
2
|
Gotoh S, Mori K, Fujino Y, Kawabe Y, Yamashita T, Omi T, Nagata K, Tagami S, Nagai Y, Ikeda M. eIF5 stimulates the CUG initiation of RAN translation of poly-GA dipeptide repeat protein (DPR) in C9orf72 FTLD/ALS. J Biol Chem 2024; 300:105703. [PMID: 38301895 PMCID: PMC10904283 DOI: 10.1016/j.jbc.2024.105703] [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: 10/18/2023] [Revised: 01/20/2024] [Accepted: 01/23/2024] [Indexed: 02/03/2024] Open
Abstract
Tandem GGGGCC repeat expansion in C9orf72 is a genetic cause of frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS). Transcribed repeats are translated into dipeptide repeat proteins via repeat-associated non-AUG (RAN) translation. However, the regulatory mechanism of RAN translation remains unclear. Here, we reveal a GTPase-activating protein, eukaryotic initiation factor 5 (eIF5), which allosterically facilitates the conversion of eIF2-bound GTP into GDP upon start codon recognition, as a novel modifier of C9orf72 RAN translation. Compared to global translation, eIF5, but not its inactive mutants, preferentially stimulates poly-GA RAN translation. RAN translation is increased during integrated stress response, but the stimulatory effect of eIF5 on poly-GA RAN translation was additive to the increase of RAN translation during integrated stress response, with no further increase in phosphorylated eIF2α. Moreover, an alteration of the CUG near cognate codon to CCG or AUG in the poly-GA reading frame abolished the stimulatory effects, indicating that eIF5 primarily acts through the CUG-dependent initiation. Lastly, in a Drosophila model of C9orf72 FTLD/ALS that expresses GGGGCC repeats in the eye, knockdown of endogenous eIF5 by two independent RNAi strains significantly reduced poly-GA expressions, confirming in vivo effect of eIF5 on poly-GA RAN translation. Together, eIF5 stimulates the CUG initiation of poly-GA RAN translation in cellular and Drosophila disease models of C9orf72 FTLD/ALS.
Collapse
Affiliation(s)
- Shiho Gotoh
- Department of Psychiatry, Osaka University Graduate School of Medicine, Suita, Japan
| | - Kohji Mori
- Department of Psychiatry, Osaka University Graduate School of Medicine, Suita, Japan.
| | - Yuzo Fujino
- Department of Neurology, Kindai University Faculty of Medicine, Osaka-Sayama, Japan; Department of Neurology, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Yuya Kawabe
- Department of Psychiatry, Osaka University Graduate School of Medicine, Suita, Japan
| | - Tomoko Yamashita
- Department of Psychiatry, Osaka University Graduate School of Medicine, Suita, Japan
| | - Tsubasa Omi
- Department of Psychiatry, Osaka University Graduate School of Medicine, Suita, Japan
| | - Kenichi Nagata
- Department of Precision Medicine for Dementia, Osaka University Graduate School of Medicine, Suita, Japan
| | - Shinji Tagami
- Department of Psychiatry, Osaka University Graduate School of Medicine, Suita, Japan
| | - Yoshitaka Nagai
- Department of Neurology, Kindai University Faculty of Medicine, Osaka-Sayama, Japan
| | - Manabu Ikeda
- Department of Psychiatry, Osaka University Graduate School of Medicine, Suita, Japan
| |
Collapse
|
3
|
Zhou L, Xie M, Wang X, Xu R. The usage and advantages of several common amyotrophic lateral sclerosis animal models. Front Neurosci 2024; 18:1341109. [PMID: 38595972 PMCID: PMC11002901 DOI: 10.3389/fnins.2024.1341109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Accepted: 01/29/2024] [Indexed: 04/11/2024] Open
Abstract
Amyotrophic lateral sclerosis is a fatal, multigenic, multifactorial neurodegenerative disease characterized by upper and lower motor neuron loss. Animal models are essential for investigating pathogenesis and reflecting clinical manifestations, particularly in developing reasonable prevention and therapeutic methods for human diseases. Over the decades, researchers have established a host of different animal models in order to dissect amyotrophic lateral sclerosis (ALS), such as yeast, worms, flies, zebrafish, mice, rats, pigs, dogs, and more recently, non-human primates. Although these models show different peculiarities, they are all useful and complementary to dissect the pathological mechanisms of motor neuron degeneration in ALS, contributing to the development of new promising therapeutics. In this review, we describe several common animal models in ALS, classified by the naturally occurring and experimentally induced, pointing out their features in modeling, the onset and progression of the pathology, and their specific pathological hallmarks. Moreover, we highlight the pros and cons aimed at helping the researcher select the most appropriate among those common experimental animal models when designing a preclinical ALS study.
Collapse
Affiliation(s)
- Lijun Zhou
- Department of Neurology, Jiangxi Provincial People’s Hospital, Clinical College of Nanchang Medical College, First Affiliated Hospital of Nanchang Medical College, National Regional Center for Neurological Diseases, Xiangya Hospital of Central South University Jiangxi Hospital, Nanchang, Jiangxi, China
- Medical College of Nanchang University, Nanchang, Jiangxi, China
| | - Meng Xie
- Health Management Center, Jiangxi Provincial People’s Hospital, The First Affiliated Hospital of Nanchang Medical College, The Clinical College of Nanchang Medical College, Nanchang, Jiangxi, China
| | - Xinxin Wang
- Department of Neurology, Jiangxi Provincial People’s Hospital, Clinical College of Nanchang Medical College, First Affiliated Hospital of Nanchang Medical College, National Regional Center for Neurological Diseases, Xiangya Hospital of Central South University Jiangxi Hospital, Nanchang, Jiangxi, China
- Medical College of Nanchang University, Nanchang, Jiangxi, China
| | - Renshi Xu
- Department of Neurology, Jiangxi Provincial People’s Hospital, Clinical College of Nanchang Medical College, First Affiliated Hospital of Nanchang Medical College, National Regional Center for Neurological Diseases, Xiangya Hospital of Central South University Jiangxi Hospital, Nanchang, Jiangxi, China
- Medical College of Nanchang University, Nanchang, Jiangxi, China
| |
Collapse
|
4
|
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.
Collapse
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
| |
Collapse
|
5
|
Zhu L, Li S, Li XJ, Yin P. Pathological insights from amyotrophic lateral sclerosis animal models: comparisons, limitations, and challenges. Transl Neurodegener 2023; 12:46. [PMID: 37730668 PMCID: PMC10510301 DOI: 10.1186/s40035-023-00377-7] [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: 06/02/2023] [Accepted: 09/01/2023] [Indexed: 09/22/2023] Open
Abstract
In order to dissect amyotrophic lateral sclerosis (ALS), a multigenic, multifactorial, and progressive neurodegenerative disease with heterogeneous clinical presentations, researchers have generated numerous animal models to mimic the genetic defects. Concurrent and comparative analysis of these various models allows identification of the causes and mechanisms of ALS in order to finally obtain effective therapeutics. However, most genetically modified rodent models lack overt pathological features, imposing challenges and limitations in utilizing them to rigorously test the potential mechanisms. Recent studies using large animals, including pigs and non-human primates, have uncovered important events that resemble neurodegeneration in patients' brains but could not be produced in small animals. Here we describe common features as well as discrepancies among these models, highlighting new insights from these models. Furthermore, we will discuss how to make rodent models more capable of recapitulating important pathological features based on the important pathogenic insights from large animal models.
Collapse
Affiliation(s)
- Longhong Zhu
- Guangdong Key Laboratory of Non-Human Primate Research, Key Laboratory of CNS Regeneration (Ministry of Education), GHM Institute of CNS Regeneration, Jinan University, Guangzhou, 510632, China
| | - Shihua Li
- Guangdong Key Laboratory of Non-Human Primate Research, Key Laboratory of CNS Regeneration (Ministry of Education), GHM Institute of CNS Regeneration, Jinan University, Guangzhou, 510632, China
| | - Xiao-Jiang Li
- Guangdong Key Laboratory of Non-Human Primate Research, Key Laboratory of CNS Regeneration (Ministry of Education), GHM Institute of CNS Regeneration, Jinan University, Guangzhou, 510632, China.
| | - Peng Yin
- Guangdong Key Laboratory of Non-Human Primate Research, Key Laboratory of CNS Regeneration (Ministry of Education), GHM Institute of CNS Regeneration, Jinan University, Guangzhou, 510632, China.
| |
Collapse
|
6
|
Marzullo M, Coni S, De Simone A, Canettieri G, Ciapponi L. Modeling Myotonic Dystrophy Type 2 Using Drosophila melanogaster. Int J Mol Sci 2023; 24:14182. [PMID: 37762484 PMCID: PMC10532015 DOI: 10.3390/ijms241814182] [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: 08/07/2023] [Revised: 09/04/2023] [Accepted: 09/13/2023] [Indexed: 09/29/2023] Open
Abstract
Myotonic dystrophy 2 (DM2) is a genetic multi-systemic disease primarily affecting skeletal muscle. It is caused by CCTGn expansion in intron 1 of the CNBP gene, which encodes a zinc finger protein. DM2 disease has been successfully modeled in Drosophila melanogaster, allowing the identification and validation of new pathogenic mechanisms and potential therapeutic strategies. Here, we describe the principal tools used in Drosophila to study and dissect molecular pathways related to muscular dystrophies and summarize the main findings in DM2 pathogenesis based on DM2 Drosophila models. We also illustrate how Drosophila may be successfully used to generate a tractable animal model to identify novel genes able to affect and/or modify the pathogenic pathway and to discover new potential drugs.
Collapse
Affiliation(s)
- Marta Marzullo
- Department of Biology and Biotechnologies “C. Darwin”, Sapienza University of Rome, 00185 Rome, Italy; (M.M.)
| | - Sonia Coni
- Department of Molecular Medicine, Sapienza University of Rome, 00161 Rome, Italy
| | - Assia De Simone
- Department of Biology and Biotechnologies “C. Darwin”, Sapienza University of Rome, 00185 Rome, Italy; (M.M.)
| | - Gianluca Canettieri
- Department of Molecular Medicine, Sapienza University of Rome, 00161 Rome, Italy
- Istituto Pasteur Italia, Fondazione Cenci Bolognetti, 00161 Rome, Italy
| | - Laura Ciapponi
- Department of Biology and Biotechnologies “C. Darwin”, Sapienza University of Rome, 00185 Rome, Italy; (M.M.)
| |
Collapse
|
7
|
Latallo MJ, Wang S, Dong D, Nelson B, Livingston NM, Wu R, Zhao N, Stasevich TJ, Bassik MC, Sun S, Wu B. Single-molecule imaging reveals distinct elongation and frameshifting dynamics between frames of expanded RNA repeats in C9ORF72-ALS/FTD. Nat Commun 2023; 14:5581. [PMID: 37696852 PMCID: PMC10495369 DOI: 10.1038/s41467-023-41339-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Accepted: 08/30/2023] [Indexed: 09/13/2023] Open
Abstract
C9ORF72 hexanucleotide repeat expansion is the most common genetic cause of both amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). One pathogenic mechanism is the accumulation of toxic dipeptide repeat (DPR) proteins like poly-GA, GP and GR, produced by the noncanonical translation of the expanded RNA repeats. However, how different DPRs are synthesized remains elusive. Here, we use single-molecule imaging techniques to directly measure the translation dynamics of different DPRs. Besides initiation, translation elongation rates vary drastically between different frames, with GP slower than GA and GR the slowest. We directly visualize frameshift events using a two-color single-molecule translation assay. The repeat expansion enhances frameshifting, but the overall frequency is low. There is a higher chance of GR-to-GA shift than in the reversed direction. Finally, the ribosome-associated protein quality control (RQC) factors ZNF598 and Pelota modulate the translation dynamics, and the repeat RNA sequence is important for invoking the RQC pathway. This study reveals that multiple translation steps modulate the final DPR production. Understanding repeat RNA translation is critically important to decipher the DPR-mediated pathogenesis and identify potential therapeutic targets in C9ORF72-ALS/FTD.
Collapse
Affiliation(s)
- Malgorzata J Latallo
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Shaopeng Wang
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Daoyuan Dong
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Blake Nelson
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Nathan M Livingston
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Rong Wu
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Ning Zhao
- Department of Biochemistry and Molecular Genetics, University of Colorado-Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Timothy J Stasevich
- Department of Biochemistry and Molecular Genetics, University of Colorado-Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Michael C Bassik
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Shuying Sun
- Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
| | - Bin Wu
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
| |
Collapse
|
8
|
Sonobe Y, Lee S, Krishnan G, Gu Y, Kwon DY, Gao FB, Roos RP, Kratsios P. Translation of dipeptide repeat proteins in C9ORF72 ALS/FTD through unique and redundant AUG initiation codons. eLife 2023; 12:e83189. [PMID: 37675986 PMCID: PMC10541178 DOI: 10.7554/elife.83189] [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: 09/02/2022] [Accepted: 09/06/2023] [Indexed: 09/08/2023] Open
Abstract
A hexanucleotide repeat expansion in C9ORF72 is the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). A hallmark of ALS/FTD pathology is the presence of dipeptide repeat (DPR) proteins, produced from both sense GGGGCC (poly-GA, poly-GP, poly-GR) and antisense CCCCGG (poly-PR, poly-PG, poly-PA) transcripts. Translation of sense DPRs, such as poly-GA and poly-GR, depends on non-canonical (non-AUG) initiation codons. Here, we provide evidence for canonical AUG-dependent translation of two antisense DPRs, poly-PR and poly-PG. A single AUG is required for synthesis of poly-PR, one of the most toxic DPRs. Unexpectedly, we found redundancy between three AUG codons necessary for poly-PG translation. Further, the eukaryotic translation initiation factor 2D (EIF2D), which was previously implicated in sense DPR synthesis, is not required for AUG-dependent poly-PR or poly-PG translation, suggesting that distinct translation initiation factors control DPR synthesis from sense and antisense transcripts. Our findings on DPR synthesis from the C9ORF72 locus may be broadly applicable to many other nucleotide repeat expansion disorders.
Collapse
Affiliation(s)
- Yoshifumi Sonobe
- University of Chicago Medical CenterChicagoUnited States
- Department of Neurology, University of Chicago Medical CenterChicagoUnited States
- Neuroscience Institute, University of ChicagoChicagoUnited States
| | - Soojin Lee
- RNA Therapeutics Institute, University of Massachusetts Chan Medical SchoolWorcesterUnited States
- Department of Neurology, University of Massachusetts Chan Medical SchoolWorcesterUnited States
| | - Gopinath Krishnan
- RNA Therapeutics Institute, University of Massachusetts Chan Medical SchoolWorcesterUnited States
- Department of Neurology, University of Massachusetts Chan Medical SchoolWorcesterUnited States
| | - Yuanzheng Gu
- Neuromuscular & Movement Disorders, BiogenCambridgeUnited States
| | - Deborah Y Kwon
- Neuromuscular & Movement Disorders, BiogenCambridgeUnited States
| | - Fen-Biao Gao
- RNA Therapeutics Institute, University of Massachusetts Chan Medical SchoolWorcesterUnited States
- Department of Neurology, University of Massachusetts Chan Medical SchoolWorcesterUnited States
| | - Raymond P Roos
- University of Chicago Medical CenterChicagoUnited States
- Department of Neurology, University of Chicago Medical CenterChicagoUnited States
- Neuroscience Institute, University of ChicagoChicagoUnited States
| | - Paschalis Kratsios
- Neuroscience Institute, University of ChicagoChicagoUnited States
- Department of Neurobiology, University of ChicagoChicagoUnited States
| |
Collapse
|
9
|
Wang S, Sun S. Translation dysregulation in neurodegenerative diseases: a focus on ALS. Mol Neurodegener 2023; 18:58. [PMID: 37626421 PMCID: PMC10464328 DOI: 10.1186/s13024-023-00642-3] [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: 01/03/2023] [Accepted: 07/21/2023] [Indexed: 08/27/2023] Open
Abstract
RNA translation is tightly controlled in eukaryotic cells to regulate gene expression and maintain proteome homeostasis. RNA binding proteins, translation factors, and cell signaling pathways all modulate the translation process. Defective translation is involved in multiple neurological diseases including amyotrophic lateral sclerosis (ALS). ALS is a progressive neurodegenerative disorder and poses a major public health challenge worldwide. Over the past few years, tremendous advances have been made in the understanding of the genetics and pathogenesis of ALS. Dysfunction of RNA metabolisms, including RNA translation, has been closely associated with ALS. Here, we first introduce the general mechanisms of translational regulation under physiological and stress conditions and review well-known examples of translation defects in neurodegenerative diseases. We then focus on ALS-linked genes and discuss the recent progress on how translation is affected by various mutant genes and the repeat expansion-mediated non-canonical translation in ALS.
Collapse
Affiliation(s)
- Shaopeng Wang
- Department of Physiology and Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Shuying Sun
- Department of Physiology and Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
| |
Collapse
|
10
|
Van't Spijker HM, Almeida S. How villains are made: The translation of dipeptide repeat proteins in C9ORF72-ALS/FTD. Gene 2023; 858:147167. [PMID: 36621656 PMCID: PMC9928902 DOI: 10.1016/j.gene.2023.147167] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 01/03/2023] [Indexed: 01/07/2023]
Abstract
A hexanucleotide repeat expansion in the C9ORF72 gene is the most common genetic alteration associated with amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). These neurodegenerative diseases share genetic, clinical and pathological features. The mutation in C9ORF72 appears to drive pathogenesis through a combination of loss of C9ORF72 normal function and gain of toxic effects due to the repeat expansion, which result in aggregation prone expanded RNAs and dipeptide repeat (DPR) proteins. Studies in cellular and animal models indicate that the DPR proteins are the more toxic species. Thus, a large body of research has focused on identifying the cellular pathways most directly impacted by these toxic proteins, with the goal of characterizing disease pathogenesis and nominating potential targets for therapeutic development. The preventative block of the production of the toxic proteins before they can cause harm is a second strategy of intense focus. Despite the considerable amount of effort dedicated to this prophylactic approach, it is still unclear how the DPR proteins are synthesized from RNAs harboring repeat expansions. In this review, we summarize our current knowledge of the specific protein translation mechanisms shown to account for the synthesis of DPR proteins. We will then discuss how enhanced understanding of the composition of these toxic effectors could help in refining disease mechanisms, and paving the way to identify and design effective prophylactic therapies for C9ORF72 ALS-FTD.
Collapse
Affiliation(s)
- Heleen M Van't Spijker
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
| | - Sandra Almeida
- Department of Neurology, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA.
| |
Collapse
|
11
|
Nitta Y, Sugie A. Studies of neurodegenerative diseases using Drosophila and the development of novel approaches for their analysis. Fly (Austin) 2022; 16:275-298. [PMID: 35765969 PMCID: PMC9336468 DOI: 10.1080/19336934.2022.2087484] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 05/31/2022] [Accepted: 06/03/2022] [Indexed: 02/09/2023] Open
Abstract
The use of Drosophila in neurodegenerative disease research has contributed to the identification of modifier genes for the pathology. The basis for neurodegenerative disease occurrence in Drosophila is the conservation of genes across species and the ability to perform rapid genetic analysis using a compact brain. Genetic findings previously discovered in Drosophila can reveal molecular pathologies involved in human neurological diseases in later years. Disease models using Drosophila began to be generated during the development of genetic engineering. In recent years, results of reverse translational research using Drosophila have been reported. In this review, we discuss research on neurodegenerative diseases; moreover, we introduce various methods for quantifying neurodegeneration in Drosophila.
Collapse
Affiliation(s)
- Yohei Nitta
- Brain Research Institute, Niigata University, Niigata, Japan
| | - Atsushi Sugie
- Brain Research Institute, Niigata University, Niigata, Japan
| |
Collapse
|
12
|
Gao J, Mewborne QT, Girdhar A, Sheth U, Coyne AN, Punathil R, Kang BG, Dasovich M, Veire A, Hernandez MD, Liu S, Shi Z, Dafinca R, Fouquerel E, Talbot K, Kam TI, Zhang YJ, Dickson D, Petrucelli L, van Blitterswijk M, Guo L, Dawson TM, Dawson VL, Leung AKL, Lloyd TE, Gendron TF, Rothstein JD, Zhang K. Poly(ADP-ribose) promotes toxicity of C9ORF72 arginine-rich dipeptide repeat proteins. Sci Transl Med 2022; 14:eabq3215. [PMID: 36103513 PMCID: PMC10359073 DOI: 10.1126/scitranslmed.abq3215] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Arginine-rich dipeptide repeat proteins (R-DPRs), abnormal translational products of a GGGGCC hexanucleotide repeat expansion in C9ORF72, play a critical role in C9ORF72-related amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), the most common genetic form of the disorders (c9ALS/FTD). R-DPRs form liquid condensates in vitro, induce stress granule formation in cultured cells, aggregate, and sometimes coaggregate with TDP-43 in postmortem tissue from patients with c9ALS/FTD. However, how these processes are regulated is unclear. Here, we show that loss of poly(ADP-ribose) (PAR) suppresses neurodegeneration in c9ALS/FTD fly models and neurons differentiated from patient-derived induced pluripotent stem cells. Mechanistically, PAR induces R-DPR condensation and promotes R-DPR-induced stress granule formation and TDP-43 aggregation. Moreover, PAR associates with insoluble R-DPR and TDP-43 in postmortem tissue from patients. These findings identified PAR as a promoter of R-DPR toxicity and thus a potential target for treating c9ALS/FTD.
Collapse
Affiliation(s)
- Junli Gao
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | | | - Amandeep Girdhar
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Udit Sheth
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Alyssa N. Coyne
- Department of Neurology, Johns Hopkins University, School of Medicine, Baltimore, MD 21205, USA
- Brain Science Institute, Johns Hopkins University, School of Medicine, Baltimore, MD 21205, USA
| | - Ritika Punathil
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Bong Gu Kang
- Department of Neurology, Johns Hopkins University, School of Medicine, Baltimore, MD 21205, USA
| | - Morgan Dasovich
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA
- Department of Chemistry, Krieger School of Arts and Sciences, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Austin Veire
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | | | - Shuaichen Liu
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Zheng Shi
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ 08854, USA
| | - Ruxandra Dafinca
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
| | - Elise Fouquerel
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Kevin Talbot
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
| | - Tae-In Kam
- Department of Neurology, Johns Hopkins University, School of Medicine, Baltimore, MD 21205, USA
| | - Yong-Jie Zhang
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Dennis Dickson
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Leonard Petrucelli
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
- Neuroscience Graduate Program, Mayo Clinic Graduate School of Biomedical Sciences, Jacksonville, FL 32224, USA
| | | | - Lin Guo
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Ted M. Dawson
- Department of Neurology, Johns Hopkins University, School of Medicine, Baltimore, MD 21205, USA
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University, School of Medicine, Baltimore, MD 21205, USA
- Department of Neuroscience, Johns Hopkins University, School of Medicine, Baltimore, MD 21205, USA
| | - Valina L. Dawson
- Department of Neurology, Johns Hopkins University, School of Medicine, Baltimore, MD 21205, USA
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University, School of Medicine, Baltimore, MD 21205, USA
- Department of Neuroscience, Johns Hopkins University, School of Medicine, Baltimore, MD 21205, USA
| | - Anthony K. L. Leung
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA
- McKusick-Nathans Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Thomas E. Lloyd
- Department of Neurology, Johns Hopkins University, School of Medicine, Baltimore, MD 21205, USA
- Department of Neuroscience, Johns Hopkins University, School of Medicine, Baltimore, MD 21205, USA
| | - Tania F. Gendron
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
- Neuroscience Graduate Program, Mayo Clinic Graduate School of Biomedical Sciences, Jacksonville, FL 32224, USA
| | - Jeffrey D. Rothstein
- Department of Neurology, Johns Hopkins University, School of Medicine, Baltimore, MD 21205, USA
- Brain Science Institute, Johns Hopkins University, School of Medicine, Baltimore, MD 21205, USA
- Department of Neuroscience, Johns Hopkins University, School of Medicine, Baltimore, MD 21205, USA
| | - Ke Zhang
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
- Neuroscience Graduate Program, Mayo Clinic Graduate School of Biomedical Sciences, Jacksonville, FL 32224, USA
- Institute of Neurological Diseases, Shenzhen Bay Laboratory, Shenzhen, Guangdong, 518132, China
| |
Collapse
|
13
|
Baud A, Derbis M, Tutak K, Sobczak K. Partners in crime: Proteins implicated in
RNA
repeat expansion diseases. WIRES RNA 2022; 13:e1709. [PMID: 35229468 PMCID: PMC9539487 DOI: 10.1002/wrna.1709] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 12/07/2021] [Accepted: 12/08/2021] [Indexed: 11/06/2022]
Affiliation(s)
- Anna Baud
- Department of Gene Expression Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University Poznan Poland
| | - Magdalena Derbis
- Department of Gene Expression Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University Poznan Poland
| | - Katarzyna Tutak
- Department of Gene Expression Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University Poznan Poland
| | - Krzysztof Sobczak
- Department of Gene Expression Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University Poznan Poland
| |
Collapse
|
14
|
Lin CC, Su H, Shiea J, Huang TL. Isobaric Tags for Relative and Absolute Quantitation Identification of Blood Proteins Relevant to Paroxetine Response in Patients With Major Depressive Disorder. Front Psychiatry 2022; 13:577857. [PMID: 35509884 PMCID: PMC9058070 DOI: 10.3389/fpsyt.2022.577857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 03/24/2022] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES Isobaric tags for relative and absolute quantitation (iTRAQ) is a proteomic investigation that could be utilized for rapid identification and quantification of proteins, which we would use to identify differentially expressed proteins in treatment responsive patients with major depressive disorder (MDD). METHODS Six treatment responsive patients of MDD were recruited, and their peripheral blood mononuclear cell (PBMC) were collected before and after 4 weeks of paroxetine treatment. iTRAQ and Mascot search engine were used to detect differentially expressed proteins, which were then validated by Western blot. RESULTS Two thousand one hundred and fifty three proteins were screened, and seven proteins showed differences of more than two-fold and 62 proteins with a differences of less than two-fold. Six proteins with commercially available antibodies were identified, and were validated by Western blot in 10 paroxetine responsive MDD patients. Putative hydroxypyruvate isomerase (HYI), eukaryotic translation initiation factor 4H (eIF4H), and RNA binding motif 8A (RBM8A) had statistically significant differences before and after treatment in the validation. Data are available via ProteomeXchange with identifier PXD028947. CONCLUSIONS By using iTRAQ and Western blot, we were able to identify HYI, eIF4H, and RAM8a to be the potential predictors of paroxetine treatment response in patients with MDD. This finding could help establish future individualized medicine.
Collapse
Affiliation(s)
- Chin-Chuen Lin
- Department of Psychiatry, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Hung Su
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung, Taiwan
| | - Jentaie Shiea
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung, Taiwan
| | - Tiao-Lai Huang
- Department of Psychiatry, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan.,Genomic and Proteomic Core Laboratory, Department of Medical Research, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| |
Collapse
|
15
|
Castelli LM, Benson BC, Huang WP, Lin YH, Hautbergue GM. RNA Helicases in Microsatellite Repeat Expansion Disorders and Neurodegeneration. Front Genet 2022; 13:886563. [PMID: 35646086 PMCID: PMC9133428 DOI: 10.3389/fgene.2022.886563] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 04/25/2022] [Indexed: 11/17/2022] Open
Abstract
Short repeated sequences of 3-6 nucleotides are causing a growing number of over 50 microsatellite expansion disorders, which mainly present with neurodegenerative features. Although considered rare diseases in relation to the relatively low number of cases, these primarily adult-onset conditions, often debilitating and fatal in absence of a cure, collectively pose a large burden on healthcare systems in an ageing world population. The pathological mechanisms driving disease onset are complex implicating several non-exclusive mechanisms of neuronal injury linked to RNA and protein toxic gain- and loss- of functions. Adding to the complexity of pathogenesis, microsatellite repeat expansions are polymorphic and found in coding as well as in non-coding regions of genes. They form secondary and tertiary structures involving G-quadruplexes and atypical helices in repeated GC-rich sequences. Unwinding of these structures by RNA helicases plays multiple roles in the expression of genes including repeat-associated non-AUG (RAN) translation of polymeric-repeat proteins with aggregating and cytotoxic properties. Here, we will briefly review the pathogenic mechanisms mediated by microsatellite repeat expansions prior to focus on the RNA helicases eIF4A, DDX3X and DHX36 which act as modifiers of RAN translation in C9ORF72-linked amyotrophic lateral sclerosis/frontotemporal dementia (C9ORF72-ALS/FTD) and Fragile X-associated tremor/ataxia syndrome (FXTAS). We will further review the RNA helicases DDX5/17, DHX9, Dicer and UPF1 which play additional roles in the dysregulation of RNA metabolism in repeat expansion disorders. In addition, we will contrast these with the roles of other RNA helicases such as DDX19/20, senataxin and others which have been associated with neurodegeneration independently of microsatellite repeat expansions. Finally, we will discuss the challenges and potential opportunities that are associated with the targeting of RNA helicases for the development of future therapeutic approaches.
Collapse
Affiliation(s)
- Lydia M Castelli
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
| | - Bridget C Benson
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
| | - Wan-Ping Huang
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
| | - Ya-Hui Lin
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
| | - Guillaume M Hautbergue
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom.,Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom.,Healthy Lifespan Institute (HELSI), University of Sheffield, Sheffield, United Kingdom
| |
Collapse
|
16
|
Park J, Lee J, Kim JH, Lee J, Park H, Lim C. ZNF598 co-translationally titrates poly(GR) protein implicated in the pathogenesis of C9ORF72-associated ALS/FTD. Nucleic Acids Res 2021; 49:11294-11311. [PMID: 34551427 PMCID: PMC8565315 DOI: 10.1093/nar/gkab834] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 09/09/2021] [Indexed: 11/13/2022] Open
Abstract
C9ORF72-derived dipeptide repeat proteins have emerged as the pathogenic cause of neurodegeneration in amyotrophic lateral sclerosis and frontotemporal dementia (C9-ALS/FTD). However, the mechanisms underlying their expression are not fully understood. Here, we demonstrate that ZNF598, the rate-limiting factor for ribosome-associated quality control (RQC), co-translationally titrates the expression of C9ORF72-derived poly(GR) protein. A Drosophila genetic screen identified key RQC factors as potent modifiers of poly(GR)-induced neurodegeneration. ZNF598 overexpression in human neuroblastoma cells inhibited the nuclear accumulation of poly(GR) protein and decreased its cytotoxicity, whereas ZNF598 deletion had opposing effects. Poly(GR)-encoding sequences in the reporter RNAs caused translational stalling and generated ribosome-associated translation products, sharing molecular signatures with canonical RQC substrates. Furthermore, ZNF598 and listerin 1, the RQC E3 ubiquitin-protein ligase, promoted poly(GR) degradation via the ubiquitin-proteasome pathway. An ALS-relevant ZNF598R69C mutant displayed loss-of-function effects on poly(GR) expression, as well as on general RQC. Moreover, RQC function was impaired in C9-ALS patient-derived neurons, whereas lentiviral overexpression of ZNF598 lowered their poly(GR) expression and suppressed proapoptotic caspase-3 activation. Taken together, we propose that an adaptive nature of the RQC-relevant ZNF598 activity allows the co-translational surveillance to cope with the atypical expression of pathogenic poly(GR) protein, thereby acquiring a neuroprotective function in C9-ALS/FTD.
Collapse
Affiliation(s)
- Jumin Park
- Department of Biological Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Jongbo Lee
- Department of Biological Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Ji-Hyung Kim
- Department of Biological Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Jongbin Lee
- Department of Biological Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Heeju Park
- Department of Biological Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Chunghun Lim
- Department of Biological Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| |
Collapse
|
17
|
Sonobe Y, Aburas J, Krishnan G, Fleming AC, Ghadge G, Islam P, Warren EC, Gu Y, Kankel MW, Brown AEX, Kiskinis E, Gendron TF, Gao FB, Roos RP, Kratsios P. A C. elegans model of C9orf72-associated ALS/FTD uncovers a conserved role for eIF2D in RAN translation. Nat Commun 2021; 12:6025. [PMID: 34654821 PMCID: PMC8519953 DOI: 10.1038/s41467-021-26303-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Accepted: 09/28/2021] [Indexed: 12/31/2022] Open
Abstract
A hexanucleotide repeat expansion GGGGCC in the non-coding region of C9orf72 is the most common cause of inherited amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Toxic dipeptide repeats (DPRs) are synthesized from GGGGCC via repeat-associated non-AUG (RAN) translation. Here, we develop C. elegans models that express, either ubiquitously or exclusively in neurons, 75 GGGGCC repeats flanked by intronic C9orf72 sequence. The worms generate DPRs (poly-glycine-alanine [poly-GA], poly-glycine-proline [poly-GP]) and poly-glycine-arginine [poly-GR]), display neurodegeneration, and exhibit locomotor and lifespan defects. Mutation of a non-canonical translation-initiating codon (CUG) upstream of the repeats selectively reduces poly-GA steady-state levels and ameliorates disease, suggesting poly-GA is pathogenic. Importantly, loss-of-function mutations in the eukaryotic translation initiation factor 2D (eif-2D/eIF2D) reduce poly-GA and poly-GP levels, and increase lifespan in both C. elegans models. Our in vitro studies in mammalian cells yield similar results. Here, we show a conserved role for eif-2D/eIF2D in DPR expression.
Collapse
Affiliation(s)
- Yoshifumi Sonobe
- grid.412578.d0000 0000 8736 9513University of Chicago Medical Center, 5841S. Maryland Avenue, Chicago, IL 60637 USA ,grid.412578.d0000 0000 8736 9513Department of Neurology, University of Chicago Medical Center, 5841S. Maryland Avenue, Chicago, IL 60637 USA ,grid.170205.10000 0004 1936 7822The Grossman Institute for Neuroscience, Quantitative Biology, and Human Behavior, University of Chicago, Chicago, IL USA
| | - Jihad Aburas
- grid.412578.d0000 0000 8736 9513University of Chicago Medical Center, 5841S. Maryland Avenue, Chicago, IL 60637 USA ,grid.170205.10000 0004 1936 7822The Grossman Institute for Neuroscience, Quantitative Biology, and Human Behavior, University of Chicago, Chicago, IL USA ,grid.170205.10000 0004 1936 7822Department of Neurobiology, University of Chicago, Chicago, IL USA
| | - Gopinath Krishnan
- grid.168645.80000 0001 0742 0364Department of Neurology, University of Massachusetts Medical School, Worcester, MA 01605 USA
| | - Andrew C. Fleming
- grid.16753.360000 0001 2299 3507The Ken & Ruth Davee Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, USA
| | - Ghanashyam Ghadge
- grid.412578.d0000 0000 8736 9513University of Chicago Medical Center, 5841S. Maryland Avenue, Chicago, IL 60637 USA ,grid.412578.d0000 0000 8736 9513Department of Neurology, University of Chicago Medical Center, 5841S. Maryland Avenue, Chicago, IL 60637 USA ,grid.170205.10000 0004 1936 7822The Grossman Institute for Neuroscience, Quantitative Biology, and Human Behavior, University of Chicago, Chicago, IL USA
| | - Priota Islam
- grid.14105.310000000122478951MRC London Institute of Medical Sciences, London, UK ,grid.7445.20000 0001 2113 8111Institute of Clinical Sciences, Imperial College London, London, UK
| | - Eleanor C. Warren
- grid.14105.310000000122478951MRC London Institute of Medical Sciences, London, UK ,grid.7445.20000 0001 2113 8111Institute of Clinical Sciences, Imperial College London, London, UK
| | - Yuanzheng Gu
- grid.417832.b0000 0004 0384 8146Neuromuscular & Movement Disorders, Biogen, Cambridge, MA 02142 USA
| | - Mark W. Kankel
- grid.417832.b0000 0004 0384 8146Neuromuscular & Movement Disorders, Biogen, Cambridge, MA 02142 USA
| | - André E. X. Brown
- grid.14105.310000000122478951MRC London Institute of Medical Sciences, London, UK ,grid.7445.20000 0001 2113 8111Institute of Clinical Sciences, Imperial College London, London, UK
| | - Evangelos Kiskinis
- grid.16753.360000 0001 2299 3507The Ken & Ruth Davee Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, USA
| | - Tania F. Gendron
- grid.417467.70000 0004 0443 9942Department of Neuroscience, Mayo Clinic, Jacksonville, FL USA
| | - Fen-Biao Gao
- grid.168645.80000 0001 0742 0364Department of Neurology, University of Massachusetts Medical School, Worcester, MA 01605 USA
| | - Raymond P. Roos
- grid.412578.d0000 0000 8736 9513University of Chicago Medical Center, 5841S. Maryland Avenue, Chicago, IL 60637 USA ,grid.412578.d0000 0000 8736 9513Department of Neurology, University of Chicago Medical Center, 5841S. Maryland Avenue, Chicago, IL 60637 USA ,grid.170205.10000 0004 1936 7822The Grossman Institute for Neuroscience, Quantitative Biology, and Human Behavior, University of Chicago, Chicago, IL USA
| | - Paschalis Kratsios
- University of Chicago Medical Center, 5841S. Maryland Avenue, Chicago, IL, 60637, USA. .,The Grossman Institute for Neuroscience, Quantitative Biology, and Human Behavior, University of Chicago, Chicago, IL, USA. .,Department of Neurobiology, University of Chicago, Chicago, IL, USA.
| |
Collapse
|
18
|
McGurk L, Rifai OM, Shcherbakova O, Perlegos AE, Byrns CN, Carranza FR, Zhou HW, Kim HJ, Zhu Y, Bonini NM. Toxicity of pathogenic ataxin-2 in Drosophila shows dependence on a pure CAG repeat sequence. Hum Mol Genet 2021; 30:1797-1810. [PMID: 34077532 PMCID: PMC8444453 DOI: 10.1093/hmg/ddab148] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 05/12/2021] [Accepted: 05/24/2021] [Indexed: 12/31/2022] Open
Abstract
Spinocerebellar ataxia type 2 is a polyglutamine (polyQ) disease associated with an expanded polyQ domain within the protein product of the ATXN2 gene. Interestingly, polyQ repeat expansions in ATXN2 are also associated with amyotrophic lateral sclerosis (ALS) and parkinsonism depending upon the length of the polyQ repeat expansion. The sequence encoding the polyQ repeat also varies with disease presentation: a pure CAG repeat is associated with SCA2, whereas the CAG repeat in ALS and parkinsonism is typically interrupted with the glutamine encoding CAA codon. Here, we asked if the purity of the CAG sequence encoding the polyQ repeat in ATXN2 could impact the toxicity of the ataxin-2 protein in vivo in Drosophila. We found that ataxin-2 encoded by a pure CAG repeat conferred toxicity in the retina and nervous system, whereas ataxin-2 encoded by a CAA-interrupted repeat or CAA-only repeat failed to confer toxicity, despite expression of the protein at similar levels. Furthermore, the CAG-encoded ataxin-2 protein aggregated in the fly eye, while ataxin-2 encoded by either a CAA/G or CAA repeat remained diffuse. The toxicity of the CAG-encoded ataxin-2 protein was also sensitive to the translation factor eIF4H, a known modifier of the toxic GGGGCC repeat in flies. These data indicate that ataxin-2 encoded by a pure CAG versus interrupted CAA/G polyQ repeat domain is associated with differential toxicity, indicating that mechanisms associated with the purity of the sequence of the polyQ domain contribute to disease.
Collapse
Affiliation(s)
- Leeanne McGurk
- Division of Cell & Developmental Biology, School of Life Sciences, University of Dundee, Dundee, UK
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - Olivia M Rifai
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | | | | | - China N Byrns
- Neurosciences Graduate Group, University of Pennsylvania, Philadelphia, PA, USA
- Medical Sciences Training Program, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Faith R Carranza
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - Henry W Zhou
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - Hyung-Jun Kim
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - Yongqing Zhu
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - Nancy M Bonini
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
- Neurosciences Graduate Group, University of Pennsylvania, Philadelphia, PA, USA
| |
Collapse
|
19
|
Goodman LD, Cope H, Nil Z, Ravenscroft TA, Charng WL, Lu S, Tien AC, Pfundt R, Koolen DA, Haaxma CA, Veenstra-Knol HE, Wassink-Ruiter JSK, Wevers MR, Jones M, Walsh LE, Klee VH, Theunis M, Legius E, Steel D, Barwick KES, Kurian MA, Mohammad SS, Dale RC, Terhal PA, van Binsbergen E, Kirmse B, Robinette B, Cogné B, Isidor B, Grebe TA, Kulch P, Hainline BE, Sapp K, Morava E, Klee EW, Macke EL, Trapane P, Spencer C, Si Y, Begtrup A, Moulton MJ, Dutta D, Kanca O, Wangler MF, Yamamoto S, Bellen HJ, Tan QKG. TNPO2 variants associate with human developmental delays, neurologic deficits, and dysmorphic features and alter TNPO2 activity in Drosophila. Am J Hum Genet 2021; 108:1669-1691. [PMID: 34314705 PMCID: PMC8456166 DOI: 10.1016/j.ajhg.2021.06.019] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 06/27/2021] [Indexed: 12/11/2022] Open
Abstract
Transportin-2 (TNPO2) mediates multiple pathways including non-classical nucleocytoplasmic shuttling of >60 cargoes, such as developmental and neuronal proteins. We identified 15 individuals carrying de novo coding variants in TNPO2 who presented with global developmental delay (GDD), dysmorphic features, ophthalmologic abnormalities, and neurological features. To assess the nature of these variants, functional studies were performed in Drosophila. We found that fly dTnpo (orthologous to TNPO2) is expressed in a subset of neurons. dTnpo is critical for neuronal maintenance and function as downregulating dTnpo in mature neurons using RNAi disrupts neuronal activity and survival. Altering the activity and expression of dTnpo using mutant alleles or RNAi causes developmental defects, including eye and wing deformities and lethality. These effects are dosage dependent as more severe phenotypes are associated with stronger dTnpo loss. Interestingly, similar phenotypes are observed with dTnpo upregulation and ectopic expression of TNPO2, showing that loss and gain of Transportin activity causes developmental defects. Further, proband-associated variants can cause more or less severe developmental abnormalities compared to wild-type TNPO2 when ectopically expressed. The impact of the variants tested seems to correlate with their position within the protein. Specifically, those that fall within the RAN binding domain cause more severe toxicity and those in the acidic loop are less toxic. Variants within the cargo binding domain show tissue-dependent effects. In summary, dTnpo is an essential gene in flies during development and in neurons. Further, proband-associated de novo variants within TNPO2 disrupt the function of the encoded protein. Hence, TNPO2 variants are causative for neurodevelopmental abnormalities.
Collapse
Affiliation(s)
- Lindsey D Goodman
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Heidi Cope
- Division of Medical Genetics, Department of Pediatrics, Duke University Medical Center, Durham, NC 27710, USA
| | - Zelha Nil
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Thomas A Ravenscroft
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Wu-Lin Charng
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Shenzhao Lu
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - An-Chi Tien
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Rolph Pfundt
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525 GA, PO Box 9101, Nijmegen, the Netherlands
| | - David A Koolen
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525 GA, PO Box 9101, Nijmegen, the Netherlands
| | - Charlotte A Haaxma
- Department of Pediatric Neurology, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, Geert Grooteplein Zuid 10, 6525 GA, PO Box 9101, the Netherlands
| | - Hermine E Veenstra-Knol
- Department of Genetics, University of Groningen, University Medical Center Groningen, 9713 GZ Groningen, the Netherlands
| | - Jolien S Klein Wassink-Ruiter
- Department of Genetics, University of Groningen, University Medical Center Groningen, 9713 GZ Groningen, the Netherlands
| | - Marijke R Wevers
- Department of Genetics, Radboud University Medical Center, PO Box 9101, 6500 HB Nijmegen, the Netherlands
| | - Melissa Jones
- Houston Area Pediatric Neurology, 24514 Kingsland Blvd, Katy, TX 77494, USA
| | - Laurence E Walsh
- Department of Pediatric Neurology, Riley Hospital for Children, Indianapolis, IN 46202, USA
| | - Victoria H Klee
- Department of Pediatric Neurology, Riley Hospital for Children, Indianapolis, IN 46202, USA
| | - Miel Theunis
- Center for Human Genetics, University Hospital Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Eric Legius
- Department of Human Genetics, University of Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Dora Steel
- Molecular Neurosciences, Developmental Neurosciences, UCL Great Ormond Street Institute of Child Health, London WC1N 1EH, UK; Department of Neurology, Great Ormond Street Hospital, London WC1N 3JH, UK
| | - Katy E S Barwick
- Molecular Neurosciences, Developmental Neurosciences, UCL Great Ormond Street Institute of Child Health, London WC1N 1EH, UK
| | - Manju A Kurian
- Molecular Neurosciences, Developmental Neurosciences, UCL Great Ormond Street Institute of Child Health, London WC1N 1EH, UK; Department of Neurology, Great Ormond Street Hospital, London WC1N 3JH, UK
| | - Shekeeb S Mohammad
- T.Y. Nelson Department of Neurology and Neurosurgery, The Children's Hospital at Westmead, Westmead, NSW 2145, Australia; Kids Neuroscience Centre, The Children's Hospital at Westmead, Faculty of Medicine and Health, Sydney Medical School, University of Sydney, Sydney, Westmead, NSW 2145, Australia
| | - Russell C Dale
- T.Y. Nelson Department of Neurology and Neurosurgery, The Children's Hospital at Westmead, Westmead, NSW 2145, Australia; Kids Neuroscience Centre, The Children's Hospital at Westmead, Faculty of Medicine and Health, Sydney Medical School, University of Sydney, Sydney, Westmead, NSW 2145, Australia
| | - Paulien A Terhal
- Department of Genetics, University Medical Center Utrecht, Lundlaan 6, 3584 EA Utrecht, the Netherlands
| | - Ellen van Binsbergen
- Department of Genetics, University Medical Center Utrecht, Lundlaan 6, 3584 EA Utrecht, the Netherlands
| | - Brian Kirmse
- Department of Pediatrics, University of Mississippi Medical Center, Jackson, MS 39216, USA
| | - Bethany Robinette
- Department of Pediatrics, University of Mississippi Medical Center, Jackson, MS 39216, USA
| | - Benjamin Cogné
- Centre hospitalier universitaire (CHU) de Nantes, Service de Génétique Médicale, 9 quai Moncousu, 44093 Nantes, France; INSERM, CNRS, UNIV Nantes, Centre hospitalier universitaire (CHU) de Nantes, l'institut du thorax, 44007 Nantes, France
| | - Bertrand Isidor
- Centre hospitalier universitaire (CHU) de Nantes, Service de Génétique Médicale, 9 quai Moncousu, 44093 Nantes, France; INSERM, CNRS, UNIV Nantes, Centre hospitalier universitaire (CHU) de Nantes, l'institut du thorax, 44007 Nantes, France
| | - Theresa A Grebe
- Phoenix Children's Hospital, Phoenix, AZ 85016, USA; Department of Child Health, University of Arizona College of Medicine Phoenix, Phoenix, AZ 85004, USA
| | - Peggy Kulch
- Phoenix Children's Hospital, Phoenix, AZ 85016, USA
| | - Bryan E Hainline
- Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Katherine Sapp
- Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Eva Morava
- Center for Individualized Medicine, Mayo Clinic, Rochester, MN 55905, USA; Department of Clinical Genomics, Mayo Clinic, Rochester, MN 55905, USA
| | - Eric W Klee
- Center for Individualized Medicine, Mayo Clinic, Rochester, MN 55905, USA; Department of Clinical Genomics, Mayo Clinic, Rochester, MN 55905, USA
| | - Erica L Macke
- Center for Individualized Medicine, Mayo Clinic, Rochester, MN 55905, USA
| | - Pamela Trapane
- University of Florida, College of Medicine, Jacksonville, Jacksonville, FL 32209, USA
| | - Christopher Spencer
- University of Florida, College of Medicine, Jacksonville, Jacksonville, FL 32209, USA
| | - Yue Si
- GeneDx, Gaithersburg, MD 20877, USA
| | | | - Matthew J Moulton
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Debdeep Dutta
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Oguz Kanca
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Michael F Wangler
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Shinya Yamamoto
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA; Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA; Development, Disease Models & Therapeutics Graduate Program, Baylor College of Medicine, Houston, TX 77030, USA
| | - Hugo J Bellen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA; Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA; Development, Disease Models & Therapeutics Graduate Program, Baylor College of Medicine, Houston, TX 77030, USA; Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA.
| | - Queenie K-G Tan
- Division of Medical Genetics, Department of Pediatrics, Duke University Medical Center, Durham, NC 27710, USA.
| |
Collapse
|
20
|
Liguori F, Amadio S, Volonté C. Fly for ALS: Drosophila modeling on the route to amyotrophic lateral sclerosis modifiers. Cell Mol Life Sci 2021; 78:6143-6160. [PMID: 34322715 PMCID: PMC11072332 DOI: 10.1007/s00018-021-03905-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/20/2021] [Accepted: 07/22/2021] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a rare, devastating disease, causing movement impairment, respiratory failure and ultimate death. A plethora of genetic, cellular and molecular mechanisms are involved in ALS signature, although the initiating causes and progressive pathological events are far from being understood. Drosophila research has produced seminal discoveries for more than a century and has been successfully used in the past 25 years to untangle the process of ALS pathogenesis, and recognize potential markers and novel strategies for therapeutic solutions. This review will provide an updated view of several ALS modifiers validated in C9ORF72, SOD1, FUS, TDP-43 and Ataxin-2 Drosophila models. We will discuss basic and preclinical findings, illustrating recent developments and novel breakthroughs, also depicting unsettled challenges and limitations in the Drosophila-ALS field. We intend to stimulate a renewed debate on Drosophila as a screening route to identify more successful disease modifiers and neuroprotective agents.
Collapse
Affiliation(s)
- Francesco Liguori
- Preclinical Neuroscience, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 65, 00143, Rome, Italy
| | - Susanna Amadio
- Preclinical Neuroscience, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 65, 00143, Rome, Italy
| | - Cinzia Volonté
- Preclinical Neuroscience, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 65, 00143, Rome, Italy.
- Institute for Systems Analysis and Computer Science "A. Ruberti", National Research Council (IASI-CNR), Via dei Taurini 19, 00185, Rome, Italy.
| |
Collapse
|
21
|
Malik I, Kelley CP, Wang ET, Todd PK. Molecular mechanisms underlying nucleotide repeat expansion disorders. Nat Rev Mol Cell Biol 2021; 22:589-607. [PMID: 34140671 PMCID: PMC9612635 DOI: 10.1038/s41580-021-00382-6] [Citation(s) in RCA: 141] [Impact Index Per Article: 47.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/30/2021] [Indexed: 02/05/2023]
Abstract
The human genome contains over one million short tandem repeats. Expansion of a subset of these repeat tracts underlies over fifty human disorders, including common genetic causes of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (C9orf72), polyglutamine-associated ataxias and Huntington disease, myotonic dystrophy, and intellectual disability disorders such as Fragile X syndrome. In this Review, we discuss the four major mechanisms by which expansion of short tandem repeats causes disease: loss of function through transcription repression, RNA-mediated gain of function through gelation and sequestration of RNA-binding proteins, gain of function of canonically translated repeat-harbouring proteins, and repeat-associated non-AUG translation of toxic repeat peptides. Somatic repeat instability amplifies these mechanisms and influences both disease age of onset and tissue specificity of pathogenic features. We focus on the crosstalk between these disease mechanisms, and argue that they often synergize to drive pathogenesis. We also discuss the emerging native functions of repeat elements and how their dynamics might contribute to disease at a larger scale than currently appreciated. Lastly, we propose that lynchpins tying these disease mechanisms and native functions together offer promising therapeutic targets with potential shared applications across this class of human disorders.
Collapse
Affiliation(s)
- Indranil Malik
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
| | - Chase P Kelley
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics, Genetics Institute, University of Florida, Gainesville, FL, USA
- Genetics and Genomics Graduate Program, University of Florida, Gainesville, FL, USA
| | - Eric T Wang
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics, Genetics Institute, University of Florida, Gainesville, FL, USA.
| | - Peter K Todd
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA.
- VA Ann Arbor Healthcare System, Ann Arbor, MI, USA.
| |
Collapse
|
22
|
Liu YJ, Chern Y. Contribution of Energy Dysfunction to Impaired Protein Translation in Neurodegenerative Diseases. Front Cell Neurosci 2021; 15:668500. [PMID: 34393724 PMCID: PMC8355359 DOI: 10.3389/fncel.2021.668500] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 07/09/2021] [Indexed: 12/14/2022] Open
Abstract
Impaired energy homeostasis and aberrant translational control have independently been implicated in the pathogenesis of neurodegenerative diseases. AMP kinase (AMPK), regulated by the ratio of cellular AMP and ATP, is a major gatekeeper for cellular energy homeostasis. Abnormal regulation of AMPK has been reported in several neurodegenerative diseases, including Alzheimer’s disease (AD) and amyotrophic lateral sclerosis (ALS). Most importantly, AMPK activation is known to suppress the translational machinery by inhibiting the mechanistic target of rapamycin complex 1 (mTORC1), activating translational regulators, and phosphorylating nuclear transporter factors. In this review, we describe recent findings on the emerging role of protein translation impairment caused by energy dysregulation in neurodegenerative diseases.
Collapse
Affiliation(s)
- Yu-Ju Liu
- Division of Neuroscience, Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Yijuang Chern
- Division of Neuroscience, Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| |
Collapse
|
23
|
Tseng YJ, Sandwith SN, Green KM, Chambers AE, Krans A, Raimer HM, Sharlow ME, Reisinger MA, Richardson AE, Routh ED, Smaldino MA, Wang YH, Vaughn JP, Todd PK, Smaldino PJ. The RNA helicase DHX36-G4R1 modulates C9orf72 GGGGCC hexanucleotide repeat-associated translation. J Biol Chem 2021; 297:100914. [PMID: 34174288 PMCID: PMC8326427 DOI: 10.1016/j.jbc.2021.100914] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 06/02/2021] [Accepted: 06/22/2021] [Indexed: 12/26/2022] Open
Abstract
GGGGCC (G4C2) hexanucleotide repeat expansions in the endosomal trafficking gene C9orf72 are the most common genetic cause of ALS and frontotemporal dementia. Repeat-associated non-AUG (RAN) translation of this expansion through near-cognate initiation codon usage and internal ribosomal entry generates toxic proteins that accumulate in patients' brains and contribute to disease pathogenesis. The helicase protein DEAH-box helicase 36 (DHX36–G4R1) plays active roles in RNA and DNA G-quadruplex (G4) resolution in cells. As G4C2 repeats are known to form G4 structures in vitro, we sought to determine the impact of manipulating DHX36 expression on repeat transcription and RAN translation. Using a series of luciferase reporter assays both in cells and in vitro, we found that DHX36 depletion suppresses RAN translation in a repeat length–dependent manner, whereas overexpression of DHX36 enhances RAN translation from G4C2 reporter RNAs. Moreover, upregulation of RAN translation that is typically triggered by integrated stress response activation is prevented by loss of DHX36. These results suggest that DHX36 is active in regulating G4C2 repeat translation, providing potential implications for therapeutic development in nucleotide repeat expansion disorders.
Collapse
Affiliation(s)
- Yi-Ju Tseng
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, USA; Cellular and Molecular Biology Graduate Program, University of Michigan, Ann Arbor, Michigan, USA
| | - Siara N Sandwith
- Department of Biology, Ball State University, Muncie, Indiana, USA
| | - Katelyn M Green
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, USA
| | | | - Amy Krans
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, USA
| | - Heather M Raimer
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, Virginia, USA
| | | | | | | | - Eric D Routh
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | | | - Yuh-Hwa Wang
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, Virginia, USA
| | - James P Vaughn
- Division of Cancer Biology, NanoMedica LLC, Winston-Salem, North Carolina, USA
| | - Peter K Todd
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, USA; Department of Neurology, Ann Arbor VA Medical Center, Ann Arbor, Michigan, USA.
| | | |
Collapse
|
24
|
Solomon DA, Smikle R, Reid MJ, Mizielinska S. Altered Phase Separation and Cellular Impact in C9orf72-Linked ALS/FTD. Front Cell Neurosci 2021; 15:664151. [PMID: 33967699 PMCID: PMC8096919 DOI: 10.3389/fncel.2021.664151] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 03/19/2021] [Indexed: 12/21/2022] Open
Abstract
Since the discovery of the C9orf72 repeat expansion mutation as causative for chromosome 9-linked amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) in 2011, a multitude of cellular pathways have been implicated. However, evidence has also been accumulating for a key mechanism of cellular compartmentalization—phase separation. Liquid-liquid phase separation (LLPS) is fundamental for the formation of membraneless organelles including stress granules, the nucleolus, Cajal bodies, nuclear speckles and the central channel of the nuclear pore. Evidence has now accumulated showing that the formation and function of these membraneless organelles is impaired by both the toxic arginine rich dipeptide repeat proteins (DPRs), translated from the C9orf72 repeat RNA transcript, and the repeat RNA itself. Both the arginine rich DPRs and repeat RNA themselves undergo phase separation and disrupt the physiological phase separation of proteins involved in the formation of these liquid-like organelles. Hence abnormal phase separation may explain a number of pathological cellular phenomena associated with C9orf72-ALS/FTD. In this review article, we will discuss the principles of phase separation, phase separation of the DPRs and repeat RNA themselves and how they perturb LLPS associated with membraneless organelles and the functional consequences of this. We will then discuss how phase separation may impact the major pathological feature of C9orf72-ALS/FTD, TDP-43 proteinopathy, and how LLPS may be targeted therapeutically in disease.
Collapse
Affiliation(s)
- Daniel A Solomon
- UK Dementia Research Institute at King's College London, London, United Kingdom.,Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, London, United Kingdom
| | - Rebekah Smikle
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, London, United Kingdom
| | - Matthew J Reid
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, London, United Kingdom
| | - Sarah Mizielinska
- UK Dementia Research Institute at King's College London, London, United Kingdom.,Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, London, United Kingdom
| |
Collapse
|
25
|
Liu H, Lu YN, Paul T, Periz G, Banco MT, Ferré-D'Amaré AR, Rothstein JD, Hayes LR, Myong S, Wang J. A Helicase Unwinds Hexanucleotide Repeat RNA G-Quadruplexes and Facilitates Repeat-Associated Non-AUG Translation. J Am Chem Soc 2021; 143:7368-7379. [PMID: 33855846 DOI: 10.1021/jacs.1c00131] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The expansion of a hexanucleotide repeat GGGGCC (G4C2) in the C9orf72 gene is the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). The G4C2 expansion leads to repeat-associated non-AUG (RAN) translation and the production of toxic dipeptide repeat (DPR) proteins, but the mechanisms of RAN translation remain enigmatic. Here, we report that the RNA helicase DHX36 is a robust positive regulator of C9orf72 RAN translation. DHX36 has a high affinity for the G4C2 repeat RNA, preferentially binds to the repeat RNA's G-quadruplex conformation, and efficiently unwinds the G4C2 G-quadruplex structures. Native DHX36 interacts with the G4C2 repeat RNA and is essential for effective RAN translation in the cell. In induced pluripotent stem cells and differentiated motor neurons derived from C9orf72-linked ALS patients, reducing DHX36 significantly decreased the levels of endogenous DPR proteins. DHX36 is also aberrantly upregulated in tissues of C9orf72-linked ALS patients. These results indicate that DHX36 facilitates C9orf72 RAN translation by resolving repeat RNA G-quadruplex structures and may be a potential target for therapeutic intervention.
Collapse
Affiliation(s)
- Honghe Liu
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland 21205, United States.,Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, Maryland 21205, United States
| | - Yu-Ning Lu
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland 21205, United States.,Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, Maryland 21205, United States
| | - Tapas Paul
- Department of Biophysics, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Goran Periz
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland 21205, United States.,Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, Maryland 21205, United States
| | - Michael T Banco
- Biochemistry and Biophysics Center, National Heart, Lung and Blood Institute, Bethesda, Maryland 20892, United States
| | - Adrian R Ferré-D'Amaré
- Biochemistry and Biophysics Center, National Heart, Lung and Blood Institute, Bethesda, Maryland 20892, United States
| | - Jeffrey D Rothstein
- Brain Science Institute and Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, United States
| | - Lindsey R Hayes
- Brain Science Institute and Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, United States
| | - Sua Myong
- Department of Biophysics, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Jiou Wang
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland 21205, United States.,Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, Maryland 21205, United States
| |
Collapse
|
26
|
Liguori F, Amadio S, Volonté C. Where and Why Modeling Amyotrophic Lateral Sclerosis. Int J Mol Sci 2021; 22:ijms22083977. [PMID: 33921446 PMCID: PMC8070525 DOI: 10.3390/ijms22083977] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 04/08/2021] [Accepted: 04/09/2021] [Indexed: 02/07/2023] Open
Abstract
Over the years, researchers have leveraged a host of different in vivo models in order to dissect amyotrophic lateral sclerosis (ALS), a neurodegenerative/neuroinflammatory disease that is heterogeneous in its clinical presentation and is multigenic, multifactorial and non-cell autonomous. These models include both vertebrates and invertebrates such as yeast, worms, flies, zebrafish, mice, rats, guinea pigs, dogs and, more recently, non-human primates. Despite their obvious differences and peculiarities, only the concurrent and comparative analysis of these various systems will allow the untangling of the causes and mechanisms of ALS for finally obtaining new efficacious therapeutics. However, harnessing these powerful organisms poses numerous challenges. In this context, we present here an updated and comprehensive review of how eukaryotic unicellular and multicellular organisms that reproduce a few of the main clinical features of the disease have helped in ALS research to dissect the pathological pathways of the disease insurgence and progression. We describe common features as well as discrepancies among these models, highlighting new insights and emerging roles for experimental organisms in ALS.
Collapse
Affiliation(s)
- Francesco Liguori
- Preclinical Neuroscience, IRCCS Santa Lucia Foundation, 00143 Rome, Italy; (F.L.); (S.A.)
| | - Susanna Amadio
- Preclinical Neuroscience, IRCCS Santa Lucia Foundation, 00143 Rome, Italy; (F.L.); (S.A.)
| | - Cinzia Volonté
- Preclinical Neuroscience, IRCCS Santa Lucia Foundation, 00143 Rome, Italy; (F.L.); (S.A.)
- Institute for Systems Analysis and Computer Science “A. Ruberti”, National Research Council (IASI—CNR), 00185 Rome, Italy
- Correspondence: ; Tel.: +39-06-50170-3084
| |
Collapse
|
27
|
Mechanisms of repeat-associated non-AUG translation in neurological microsatellite expansion disorders. Biochem Soc Trans 2021; 49:775-792. [PMID: 33729487 PMCID: PMC8106499 DOI: 10.1042/bst20200690] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 02/20/2021] [Accepted: 02/23/2021] [Indexed: 02/08/2023]
Abstract
Repeat-associated non-AUG (RAN) translation was discovered in 2011 in spinocerebellar ataxia type 8 (SCA8) and myotonic dystrophy type 1 (DM1). This non-canonical form of translation occurs in all reading frames from both coding and non-coding regions of sense and antisense transcripts carrying expansions of trinucleotide to hexanucleotide repeat sequences. RAN translation has since been reported in 7 of the 53 known microsatellite expansion disorders which mainly present with neurodegenerative features. RAN translation leads to the biosynthesis of low-complexity polymeric repeat proteins with aggregating and cytotoxic properties. However, the molecular mechanisms and protein factors involved in assembling functional ribosomes in absence of canonical AUG start codons remain poorly characterised while secondary repeat RNA structures play key roles in initiating RAN translation. Here, we briefly review the repeat expansion disorders, their complex pathogenesis and the mechanisms of physiological translation initiation together with the known factors involved in RAN translation. Finally, we discuss research challenges surrounding the understanding of pathogenesis and future directions that may provide opportunities for the development of novel therapeutic approaches for this group of incurable neurodegenerative diseases.
Collapse
|
28
|
Cunningham KM, Maulding K, Ruan K, Senturk M, Grima JC, Sung H, Zuo Z, Song H, Gao J, Dubey S, Rothstein JD, Zhang K, Bellen HJ, Lloyd TE. TFEB/Mitf links impaired nuclear import to autophagolysosomal dysfunction in C9-ALS. eLife 2020; 9:59419. [PMID: 33300868 PMCID: PMC7758070 DOI: 10.7554/elife.59419] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 12/09/2020] [Indexed: 12/13/2022] Open
Abstract
Disrupted nucleocytoplasmic transport (NCT) has been implicated in neurodegenerative disease pathogenesis; however, the mechanisms by which disrupted NCT causes neurodegeneration remain unclear. In a Drosophila screen, we identified ref(2)P/p62, a key regulator of autophagy, as a potent suppressor of neurodegeneration caused by the GGGGCC hexanucleotide repeat expansion (G4C2 HRE) in C9orf72 that causes amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). We found that p62 is increased and forms ubiquitinated aggregates due to decreased autophagic cargo degradation. Immunofluorescence and electron microscopy of Drosophila tissues demonstrate an accumulation of lysosome-like organelles that precedes neurodegeneration. These phenotypes are partially caused by cytoplasmic mislocalization of Mitf/TFEB, a key transcriptional regulator of autophagolysosomal function. Additionally, TFEB is mislocalized and downregulated in human cells expressing GGGGCC repeats and in C9-ALS patient motor cortex. Our data suggest that the C9orf72-HRE impairs Mitf/TFEB nuclear import, thereby disrupting autophagy and exacerbating proteostasis defects in C9-ALS/FTD.
Collapse
Affiliation(s)
- Kathleen M Cunningham
- Cellular and Molecular Medicine Program, School of Medicine, Johns Hopkins University, Baltimore, United States
| | - Kirstin Maulding
- Cellular and Molecular Medicine Program, School of Medicine, Johns Hopkins University, Baltimore, United States
| | - Kai Ruan
- Department of Neurology, School of Medicine, Johns Hopkins University, Baltimore, United States
| | - Mumine Senturk
- Program in Developmental Biology, Baylor College of Medicine (BCM), Houston, United States
| | - Jonathan C Grima
- Brain Science Institute, School of Medicine, Johns Hopkins University, Baltimore, United States.,Solomon H. Snyder Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, United States
| | - Hyun Sung
- Department of Neurology, School of Medicine, Johns Hopkins University, Baltimore, United States
| | - Zhongyuan Zuo
- Department of Molecular and Human Genetics, BCM, Houston, United States
| | - Helen Song
- Department of Neurology, School of Medicine, Johns Hopkins University, Baltimore, United States
| | - Junli Gao
- Department of Neuroscience, Mayo Clinic, Jacksonville, United States
| | - Sandeep Dubey
- Department of Neurology, School of Medicine, Johns Hopkins University, Baltimore, United States
| | - Jeffrey D Rothstein
- Cellular and Molecular Medicine Program, School of Medicine, Johns Hopkins University, Baltimore, United States.,Department of Neurology, School of Medicine, Johns Hopkins University, Baltimore, United States.,Brain Science Institute, School of Medicine, Johns Hopkins University, Baltimore, United States.,Solomon H. Snyder Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, United States
| | - Ke Zhang
- Department of Neuroscience, Mayo Clinic, Jacksonville, United States
| | - Hugo J Bellen
- Program in Developmental Biology, Baylor College of Medicine (BCM), Houston, United States.,Department of Molecular and Human Genetics, BCM, Houston, United States.,Department of Neuroscience, BCM, Houston, United States.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, United States.,Howard Hughes Medical Institute, Houston, United States
| | - Thomas E Lloyd
- Cellular and Molecular Medicine Program, School of Medicine, Johns Hopkins University, Baltimore, United States.,Department of Neurology, School of Medicine, Johns Hopkins University, Baltimore, United States.,Solomon H. Snyder Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, United States
| |
Collapse
|
29
|
Jazurek-Ciesiolka M, Ciesiolka A, Komur AA, Urbanek-Trzeciak MO, Krzyzosiak WJ, Fiszer A. RAN Translation of the Expanded CAG Repeats in the SCA3 Disease Context. J Mol Biol 2020; 432:166699. [PMID: 33157084 DOI: 10.1016/j.jmb.2020.10.033] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 10/26/2020] [Accepted: 10/26/2020] [Indexed: 01/08/2023]
Abstract
Spinocerebellar ataxia type 3 (SCA3) is a progressive neurodegenerative disorder caused by a CAG repeat expansion in the ATXN3 gene encoding the ataxin-3 protein. Despite extensive research the exact pathogenic mechanisms of SCA3 are still not understood in depth. In the present study, to gain insight into the toxicity induced by the expanded CAG repeats in SCA3, we comprehensively investigated repeat-associated non-ATG (RAN) translation in various cellular models expressing translated or non-canonically translated ATXN3 sequences with an increasing number of CAG repeats. We demonstrate that two SCA3 RAN proteins, polyglutamine (polyQ) and polyalanine (polyA), are found only in the case of CAG repeats of pathogenic length. Despite having distinct cellular localization, RAN polyQ and RAN polyA proteins are very often coexpressed in the same cell, impairing nuclear integrity and inducing apoptosis. We provide for the first time mechanistic insights into SCA3 RAN translation indicating that ATXN3 sequences surrounding the repeat region have an impact on SCA3 RAN translation initiation and efficiency. We revealed that RAN translation of polyQ proteins starts at non-cognate codons upstream of the CAG repeats, whereas RAN polyA proteins are likely translated within repeats. Furthermore, integrated stress response activation enhances SCA3 RAN translation. Our findings suggest that the ATXN3 sequence context plays an important role in triggering SCA3 RAN translation and that SCA3 RAN proteins may cause cellular toxicity.
Collapse
Affiliation(s)
- Magdalena Jazurek-Ciesiolka
- Department of Medical Biotechnology, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland.
| | - Adam Ciesiolka
- Department of Medical Biotechnology, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
| | - Alicja A Komur
- Department of Medical Biotechnology, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
| | - Martyna O Urbanek-Trzeciak
- Department of Medical Biotechnology, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
| | - Wlodzimierz J Krzyzosiak
- Department of Medical Biotechnology, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
| | - Agnieszka Fiszer
- Department of Medical Biotechnology, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland.
| |
Collapse
|
30
|
Skariah G, Todd PK. Translational control in aging and neurodegeneration. WILEY INTERDISCIPLINARY REVIEWS-RNA 2020; 12:e1628. [PMID: 32954679 DOI: 10.1002/wrna.1628] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 08/19/2020] [Accepted: 09/07/2020] [Indexed: 12/13/2022]
Abstract
Protein metabolism plays central roles in age-related decline and neurodegeneration. While a large body of research has explored age-related changes in protein degradation, alterations in the efficiency and fidelity of protein synthesis with aging are less well understood. Age-associated changes occur in both the protein synthetic machinery (ribosomal proteins and rRNA) and within regulatory factors controlling translation. At the same time, many of the interventions that prolong lifespan do so in part by pre-emptively decreasing protein synthesis rates to allow better harmonization to age-related declines in protein catabolism. Here we review the roles of translation regulation in aging, with a specific focus on factors implicated in age-related neurodegeneration. We discuss how emerging technologies such as ribosome profiling and superior mass spectrometric approaches are illuminating age-dependent mRNA-specific changes in translation rates across tissues to reveal a critical interplay between catabolic and anabolic pathways that likely contribute to functional decline. These new findings point to nodes in posttranscriptional gene regulation that both contribute to aging and offer targets for therapy. This article is categorized under: Translation > Translation Regulation Translation > Ribosome Biogenesis Translation > Translation Mechanisms.
Collapse
Affiliation(s)
- Geena Skariah
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, USA
| | - Peter K Todd
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, USA
- Ann Arbor VA Healthcare System, Department of Veterans Affairs, Ann Arbor, Michigan, USA
| |
Collapse
|
31
|
Tang X, Toro A, T G S, Gao J, Chalk J, Oskarsson B, Zhang K. Divergence, Convergence, and Therapeutic Implications: A Cell Biology Perspective of C9ORF72-ALS/FTD. Mol Neurodegener 2020; 15:34. [PMID: 32513219 PMCID: PMC7282082 DOI: 10.1186/s13024-020-00383-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Accepted: 05/26/2020] [Indexed: 12/12/2022] Open
Abstract
Ever since a GGGGCC hexanucleotide repeat expansion mutation in C9ORF72 was identified as the most common cause of familial amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), three competing but nonexclusive hypotheses to explain how this mutation causes diseases have been proposed and are still under debate. Recent studies in the field have tried to understand how the repeat expansion disrupts cellular physiology, which has suggested interesting convergence of these hypotheses on downstream, functional defects in cells, such as nucleocytoplasmic transport disruption, membrane-less organelle defects, and DNA damage. These studies have not only provided an integrated view of the disease mechanism but also revealed novel cell biology implicated in neurodegeneration. Furthermore, some of the discoveries have given rise to new ideas for therapeutic development. Here, we review the research progress on cellular pathophysiology of C9ORF72-mediated ALS and FTD and its therapeutic implication. We suggest that the repeat expansion drives pathogenesis through a combination of downstream defects, of which some can be therapeutic targets.
Collapse
Affiliation(s)
- Xiaoqiang Tang
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Arturo Toro
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Sahana T G
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Junli Gao
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Jessica Chalk
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | | | - Ke Zhang
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA. .,Neuroscience Graduate Program, Mayo Clinic Graduate School of Biomedical Sciences, Jacksonville, FL, USA.
| |
Collapse
|
32
|
Bolus H, Crocker K, Boekhoff-Falk G, Chtarbanova S. Modeling Neurodegenerative Disorders in Drosophila melanogaster. Int J Mol Sci 2020; 21:E3055. [PMID: 32357532 PMCID: PMC7246467 DOI: 10.3390/ijms21093055] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 04/14/2020] [Accepted: 04/21/2020] [Indexed: 12/12/2022] Open
Abstract
Drosophila melanogaster provides a powerful genetic model system in which to investigate the molecular mechanisms underlying neurodegenerative diseases. In this review, we discuss recent progress in Drosophila modeling Alzheimer's Disease, Parkinson's Disease, Amyotrophic Lateral Sclerosis (ALS), Huntington's Disease, Ataxia Telangiectasia, and neurodegeneration related to mitochondrial dysfunction or traumatic brain injury. We close by discussing recent progress using Drosophila models of neural regeneration and how these are likely to provide critical insights into future treatments for neurodegenerative disorders.
Collapse
Affiliation(s)
- Harris Bolus
- Department of Biological Sciences, University of Alabama, Tuscaloosa, AL 35487, USA;
| | - Kassi Crocker
- Genetics Graduate Training Program, School of Medicine and Public Health, University of Wisconsin–Madison, Madison, WI 53705, USA;
- Department of Cell and Regenerative Biology, School of Medicine and Public Health, University of Wisconsin–Madison, Madison, WI 53705, USA
| | - Grace Boekhoff-Falk
- Department of Cell and Regenerative Biology, School of Medicine and Public Health, University of Wisconsin–Madison, Madison, WI 53705, USA
| | | |
Collapse
|
33
|
Abstract
The (GGGGCC)n repeat expansion in C9orf72, which is the most common cause of frontotemporal dementia and amyotrophic lateral sclerosis, is translated through repeat-associated non-AUG (RAN) translation. In this issue of Neuron, Cheng et al. (2019) report that the helicase DDX3X, which unwinds (or relaxes) RNA, suppresses RAN translation and toxicity.
Collapse
Affiliation(s)
- Katherine M Wilson
- UK Dementia Research Institute at UCL, Gower Street, London WC1E 6BT, UK; Department of Neurodegenerative Disease, Queen Square UCL Institute of Neurology, London WC1N 3BG, UK
| | - Bhavana Muralidharan
- UK Dementia Research Institute at UCL, Gower Street, London WC1E 6BT, UK; Department of Neurodegenerative Disease, Queen Square UCL Institute of Neurology, London WC1N 3BG, UK; Brain Development and Disease Mechanisms, Institute for Stem Cell Biology and Regenerative Medicine (inStem), Bangalore, India, 560065
| | - Adrian M Isaacs
- UK Dementia Research Institute at UCL, Gower Street, London WC1E 6BT, UK; Department of Neurodegenerative Disease, Queen Square UCL Institute of Neurology, London WC1N 3BG, UK.
| |
Collapse
|
34
|
Goodman LD, Bonini NM. Repeat-associated non-AUG (RAN) translation mechanisms are running into focus for GGGGCC-repeat associated ALS/FTD. Prog Neurobiol 2019; 183:101697. [PMID: 31550516 DOI: 10.1016/j.pneurobio.2019.101697] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2019] [Revised: 08/31/2019] [Accepted: 09/17/2019] [Indexed: 12/12/2022]
Abstract
Many human diseases are associated with the expansion of repeat sequences within the genes. It has become clear that expressed disease transcripts bearing such long repeats can undergo translation, even in the absence of a canonical AUG start codon. Termed "RAN translation" for repeat associated non-AUG translation, this process is becoming increasingly prominent as a contributor to these disorders. Here we discuss mechanisms and variables that impact translation of the repeat sequences associated with the C9orf72 gene. Expansions of a G4C2 repeat within intron 1 of this gene are associated with the motor neuron disease ALS and dementia FTD, which comprise a clinical and pathological spectrum. RAN translation of G4C2 repeat expansions has been studied in cells in culture (ex vivo) and in the fly in vivo. Cellular states that lead to RAN translation, like stress, may be critical contributors to disease progression. Greater elucidation of the mechanisms that impact this process and the factors contributing will lead to greater understanding of the repeat expansion diseases, to the potential development of novel approaches to therapeutics, and to a greater understanding of how these players impact biological processes in the absence of disease.
Collapse
Affiliation(s)
- Lindsey D Goodman
- Neuroscience Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Nancy M Bonini
- Neuroscience Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA.
| |
Collapse
|