1
|
Tadenev ALD, Hatton CL, Burgess RW. Lack of effect from genetic deletion of Hdac6 in a humanized mouse model of CMT2D. J Peripher Nerv Syst 2024; 29:213-220. [PMID: 38551018 PMCID: PMC11209801 DOI: 10.1111/jns.12623] [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: 02/11/2024] [Revised: 03/11/2024] [Accepted: 03/18/2024] [Indexed: 06/27/2024]
Abstract
BACKGROUND Inhibition of HDAC6 has been proposed as a broadly applicable therapeutic strategy for Charcot-Marie-Tooth disease (CMT). Inhibition of HDAC6 increases the acetylation of proteins important in axonal trafficking, such as α-tubulin and Miro, and has been shown to be efficacious in several preclinical studies using mouse models of CMT. AIMS Here, we sought to expand on previous preclinical studies by testing the effect of genetic deletion of Hdac6 on mice carrying a humanized knockin allele of Gars1, a model of CMT-type 2D. METHODS Gars1ΔETAQ mice were bred to an Hdac6 knockout strain, and the resulting offspring were evaluated for clinically relevant outcomes. RESULTS The genetic deletion of Hdac6 increased α-tubulin acetylation in the sciatic nerves of both wild-type and Gars1ΔETAQ mice. However, when tested at 5 weeks of age, the Gars1ΔETAQ mice lacking Hdac6 showed no changes in body weight, muscle atrophy, grip strength or endurance, sciatic motor nerve conduction velocity, compound muscle action potential amplitude, or peripheral nerve histopathology compared to Gars1ΔETAQ mice with intact Hdac6. INTERPRETATION Our results differ from those of two previous studies that demonstrated the benefit of the HDAC6 inhibitor tubastatin A in mouse models of CMT2D. While we cannot fully explain the different outcomes, our results offer a counterexample to the benefit of inhibiting HDAC6 in CMT2D, suggesting additional research is necessary.
Collapse
|
2
|
Murray GC, Hines TJ, Tadenev ALD, Xu I, Züchner S, Burgess RW. Testing SIPA1L2 as a modifier of CMT1A using mouse models. J Neuropathol Exp Neurol 2024; 83:318-330. [PMID: 38472136 PMCID: PMC11029467 DOI: 10.1093/jnen/nlae020] [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] [Indexed: 03/14/2024] Open
Abstract
Charcot-Marie-Tooth disease type 1A (CMT1A) is a demyelinating peripheral neuropathy caused by the duplication of peripheral myelin protein 22 (PMP22), leading to muscle weakness and loss of sensation in the hands and feet. A recent case-only genome-wide association study of CMT1A patients conducted by the Inherited Neuropathy Consortium identified a strong association between strength of foot dorsiflexion and variants in signal induced proliferation associated 1 like 2 (SIPA1L2), indicating that it may be a genetic modifier of disease. To validate SIPA1L2 as a candidate modifier and to assess its potential as a therapeutic target, we engineered mice with deletion of exon 1 (including the start codon) of the Sipa1l2 gene and crossed them to the C3-PMP22 mouse model of CMT1A. Neuromuscular phenotyping showed that Sipa1l2 deletion in C3-PMP22 mice preserved muscular endurance assayed by inverted wire hang duration and changed femoral nerve axon morphometrics such as myelin thickness. Gene expression changes suggest involvement of Sipa1l2 in cholesterol biosynthesis, a pathway that is also implicated in C3-PMP22 mice. Although Sipa1l2 deletion did impact CMT1A-associated phenotypes, thereby validating a genetic interaction, the overall effect on neuropathy was mild.
Collapse
Affiliation(s)
- George C Murray
- The Jackson Laboratory, Bar Harbor, Maine, USA
- The Graduate School of Biomedical Science and Engineering, The University of Maine, Orono, Maine, USA
| | | | | | - Isaac Xu
- Department of Human Genetics and John P Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Stephan Züchner
- Department of Human Genetics and John P Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Robert W Burgess
- The Jackson Laboratory, Bar Harbor, Maine, USA
- The Graduate School of Biomedical Science and Engineering, The University of Maine, Orono, Maine, USA
| |
Collapse
|
3
|
Rhymes ER, Simkin RL, Qu J, Villarroel-Campos D, Surana S, Tong Y, Shapiro R, Burgess RW, Yang XL, Schiavo G, Sleigh JN. Boosting BDNF in muscle rescues impaired axonal transport in a mouse model of DI-CMTC peripheral neuropathy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.04.09.536152. [PMID: 38559020 PMCID: PMC10979848 DOI: 10.1101/2023.04.09.536152] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Charcot-Marie-Tooth disease (CMT) is a genetic peripheral neuropathy caused by mutations in many functionally diverse genes. The aminoacyl-tRNA synthetase (ARS) enzymes, which transfer amino acids to partner tRNAs for protein synthesis, represent the largest protein family genetically linked to CMT aetiology, suggesting pathomechanistic commonalities. Dominant intermediate CMT type C (DI-CMTC) is caused by YARS1 mutations driving a toxic gain-of-function in the encoded tyrosyl-tRNA synthetase (TyrRS), which is mediated by exposure of consensus neomorphic surfaces through conformational changes of the mutant protein. In this study, we first showed that human DI-CMTC-causing TyrRSE196K mis-interacts with the extracellular domain of the BDNF receptor TrkB, an aberrant association we have previously characterised for several mutant glycyl-tRNA synthetases linked to CMT type 2D (CMT2D). We then performed temporal neuromuscular assessments of YarsE196K mice modelling DI-CMT. We determined that YarsE196K homozygotes display a selective, age-dependent impairment in in vivo axonal transport of neurotrophin-containing signalling endosomes, phenocopying CMT2D mice. This impairment is replicated by injection of recombinant TyrRSE196K, but not TyrRSWT, into muscles of wild-type mice. Augmenting BDNF in DI-CMTC muscles, through injection of recombinant protein or muscle-specific gene therapy, resulted in complete axonal transport correction. Therefore, this work identifies a non-cell autonomous pathomechanism common to ARS-related neuropathies, and highlights the potential of boosting BDNF levels in muscles as a therapeutic strategy.
Collapse
Affiliation(s)
- Elena R. Rhymes
- Department of Neuromuscular Diseases and UCL Queen Square Motor Neuron Disease Centre, Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK
| | - Rebecca L. Simkin
- Department of Neuromuscular Diseases and UCL Queen Square Motor Neuron Disease Centre, Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK
| | - Ji Qu
- Department of Neuromuscular Diseases and UCL Queen Square Motor Neuron Disease Centre, Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK
| | - David Villarroel-Campos
- Department of Neuromuscular Diseases and UCL Queen Square Motor Neuron Disease Centre, Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK
- UK Dementia Research Institute at University College London, London WC1N 3BG, UK
| | - Sunaina Surana
- Department of Neuromuscular Diseases and UCL Queen Square Motor Neuron Disease Centre, Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK
- UK Dementia Research Institute at University College London, London WC1N 3BG, UK
| | - Yao Tong
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Ryan Shapiro
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA
| | | | - Xiang-Lei Yang
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Giampietro Schiavo
- Department of Neuromuscular Diseases and UCL Queen Square Motor Neuron Disease Centre, Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK
- UK Dementia Research Institute at University College London, London WC1N 3BG, UK
| | - James N. Sleigh
- Department of Neuromuscular Diseases and UCL Queen Square Motor Neuron Disease Centre, Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK
- UK Dementia Research Institute at University College London, London WC1N 3BG, UK
| |
Collapse
|
4
|
Beijer D, Marte S, Li JC, De Ridder W, Chen JZ, Tadenev ALD, Miers KE, Deconinck T, Macdonell R, Marques W, De Jonghe P, Pratt SL, Meyer-Schuman R, Züchner S, Antonellis A, Burgess RW, Baets J. Dominant NARS1 mutations causing axonal Charcot-Marie-Tooth disease expand NARS1-associated diseases. Brain Commun 2024; 6:fcae070. [PMID: 38495304 PMCID: PMC10943570 DOI: 10.1093/braincomms/fcae070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 01/12/2024] [Accepted: 03/06/2024] [Indexed: 03/19/2024] Open
Abstract
Pathogenic variants in six aminoacyl-tRNA synthetase (ARS) genes are implicated in neurological disorders, most notably inherited peripheral neuropathies. ARSs are enzymes that charge tRNA molecules with cognate amino acids. Pathogenic variants in asparaginyl-tRNA synthetase (NARS1) cause a neurological phenotype combining developmental delay, ataxia and demyelinating peripheral neuropathy. NARS1 has not yet been linked to axonal Charcot-Marie-Tooth disease. Exome sequencing of patients with inherited peripheral neuropathies revealed three previously unreported heterozygous NARS1 variants in three families. Clinical and electrophysiological details were assessed. We further characterized all three variants in a yeast complementation model and used a knock-in mouse model to study variant p.Ser461Phe. All three variants (p.Met236del, p.Cys342Tyr and p.Ser461Phe) co-segregate with the sensorimotor axonal neuropathy phenotype. Yeast complementation assays show that none of the three NARS1 variants support wild-type yeast growth when tested in isolation (i.e. in the absence of a wild-type copy of NARS1), consistent with a loss-of-function effect. Similarly, the homozygous knock-in mouse model (p.Ser461Phe/Ser472Phe in mouse) also demonstrated loss-of-function characteristics. We present three previously unreported NARS1 variants segregating with a sensorimotor neuropathy phenotype in three families. Functional studies in yeast and mouse support variant pathogenicity. Thus, NARS1 is the seventh ARS implicated in dominant axonal Charcot-Marie-Tooth disease, further stressing that all dimeric ARSs should be evaluated for Charcot-Marie-Tooth disease.
Collapse
Affiliation(s)
- Danique Beijer
- Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Wilrijk, B-2610, Belgium
- Laboratory of Neuromuscular Pathology, Institute Born-Bunge, University of Antwerp, Wilrijk, B-2610, Belgium
- Department for Human Genetics and John P. Hussman Institute for Human Genomics, University of Miami, Miami, FL 33136, USA
| | - Sheila Marte
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Jiaxin C Li
- The Jackson Laboratory, Bar Harbor, ME 04609, USA
- Genetics Program, Graduate School of Biomedical Sciences, Tufts University, Boston, MA 02111, USA
| | - Willem De Ridder
- Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Wilrijk, B-2610, Belgium
- Laboratory of Neuromuscular Pathology, Institute Born-Bunge, University of Antwerp, Wilrijk, B-2610, Belgium
- Neuromuscular Reference Centre, Department of Neurology, Antwerp University Hospital, Wilrijk, B-2610, Belgium
| | - Jessie Z Chen
- Department of Neurology, Austin Health, Melbourne, VIC 3084, Australia
| | | | | | - Tine Deconinck
- Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Wilrijk, B-2610, Belgium
- Center of Medical Genetics, University of Antwerp and Antwerp University Hospital, Edegem, B-2650, Belgium
| | - Richard Macdonell
- Department of Neurology, Austin Health, Melbourne, VIC 3084, Australia
| | - Wilson Marques
- Department of Neurosciences and Behavior Sciences, School of Medicine of Ribeirão Preto, University of São Paulo, São Paulo, SP, 14051-140, Brazil
| | - Peter De Jonghe
- Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Wilrijk, B-2610, Belgium
- Laboratory of Neuromuscular Pathology, Institute Born-Bunge, University of Antwerp, Wilrijk, B-2610, Belgium
- Neuromuscular Reference Centre, Department of Neurology, Antwerp University Hospital, Wilrijk, B-2610, Belgium
| | - Samia L Pratt
- The Jackson Laboratory, Bar Harbor, ME 04609, USA
- Neuroscience Program, Graduate School of Biomedical Sciences, Tufts University, Boston, MA 02111, USA
| | | | - Stephan Züchner
- Department for Human Genetics and John P. Hussman Institute for Human Genomics, University of Miami, Miami, FL 33136, USA
| | - Anthony Antonellis
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48109, USA
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Robert W Burgess
- The Jackson Laboratory, Bar Harbor, ME 04609, USA
- Genetics Program, Graduate School of Biomedical Sciences, Tufts University, Boston, MA 02111, USA
- Neuroscience Program, Graduate School of Biomedical Sciences, Tufts University, Boston, MA 02111, USA
| | - Jonathan Baets
- Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Wilrijk, B-2610, Belgium
- Laboratory of Neuromuscular Pathology, Institute Born-Bunge, University of Antwerp, Wilrijk, B-2610, Belgium
- Neuromuscular Reference Centre, Department of Neurology, Antwerp University Hospital, Wilrijk, B-2610, Belgium
| |
Collapse
|
5
|
Murray GC, Hines TJ, Tadenev ALD, Xu I, Züchner S, Burgess RW. Testing SIPA1L2 as a modifier of CMT1A using mouse models. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.30.569428. [PMID: 38076977 PMCID: PMC10705403 DOI: 10.1101/2023.11.30.569428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/17/2023]
Abstract
Charcot-Marie-Tooth 1A is a demyelinating peripheral neuropathy caused by the duplication of peripheral myelin protein 22 (PMP22), which produces muscle weakness and loss of sensation in the hands and feet. A recent case-only genome wide association study by the Inherited Neuropathy Consortium identified a strong association between variants in signal induced proliferation associated 1 like 2 (SIPA1L2) and strength of foot dorsiflexion. To validate SIPA1L2 as a candidate modifier, and to assess its potential as a therapeutic target, we engineered mice with a deletion in SIPA1L2 and crossed them to the C3-PMP22 mouse model of CMT1A. We performed neuromuscular phenotyping and identified an interaction between Sipa1l2 deletion and muscular endurance decrements assayed by wire-hang duration in C3-PMP22 mice, as well as several interactions in femoral nerve axon morphometrics such as myelin thickness. Gene expression changes suggested an involvement of Sipa1l2 in cholesterol biosynthesis, which was also implicated in C3-PMP22 mice. Though several interactions between Sipa1l2 deletion and CMT1A-associated phenotypes were identified, validating a genetic interaction, the overall effect on neuropathy was small.
Collapse
Affiliation(s)
- George C Murray
- The Jackson Laboratory, Bar Harbor, ME 04609
- The Graduate School of Biomedical Science and Engineering, The University of Maine, Orono, ME 04469
| | | | | | - Isaac Xu
- Department of Human Genetics and John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Stephan Züchner
- Department of Human Genetics and John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Robert W Burgess
- The Jackson Laboratory, Bar Harbor, ME 04609
- The Graduate School of Biomedical Science and Engineering, The University of Maine, Orono, ME 04469
| |
Collapse
|
6
|
Tijaro-Bulla S, Nyandwi SP, Cui H. Physiological and engineered tRNA aminoacylation. WILEY INTERDISCIPLINARY REVIEWS. RNA 2023; 14:e1789. [PMID: 37042417 DOI: 10.1002/wrna.1789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 03/11/2023] [Accepted: 03/21/2023] [Indexed: 04/13/2023]
Abstract
Aminoacyl-tRNA synthetases form the protein family that controls the interpretation of the genetic code, with tRNA aminoacylation being the key chemical step during which an amino acid is assigned to a corresponding sequence of nucleic acids. In consequence, aminoacyl-tRNA synthetases have been studied in their physiological context, in disease states, and as tools for synthetic biology to enable the expansion of the genetic code. Here, we review the fundamentals of aminoacyl-tRNA synthetase biology and classification, with a focus on mammalian cytoplasmic enzymes. We compile evidence that the localization of aminoacyl-tRNA synthetases can be critical in health and disease. In addition, we discuss evidence from synthetic biology which made use of the importance of subcellular localization for efficient manipulation of the protein synthesis machinery. This article is categorized under: RNA Processing Translation > Translation Regulation RNA Processing > tRNA Processing RNA Export and Localization > RNA Localization.
Collapse
Affiliation(s)
| | | | - Haissi Cui
- Department of Chemistry, University of Toronto, Toronto, Ontario, Canada
| |
Collapse
|
7
|
Meyer-Schuman R, Marte S, Smith TJ, Feely SME, Kennerson M, Nicholson G, Shy ME, Koutmou KS, Antonellis A. A humanized yeast model reveals dominant-negative properties of neuropathy-associated alanyl-tRNA synthetase mutations. Hum Mol Genet 2023; 32:2177-2191. [PMID: 37010095 PMCID: PMC10281750 DOI: 10.1093/hmg/ddad054] [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: 01/04/2023] [Revised: 03/29/2023] [Accepted: 03/30/2023] [Indexed: 04/04/2023] Open
Abstract
Aminoacyl-tRNA synthetases (ARSs) are essential enzymes that ligate tRNA molecules to cognate amino acids. Heterozygosity for missense variants or small in-frame deletions in six ARS genes causes dominant axonal peripheral neuropathy. These pathogenic variants reduce enzyme activity without significantly decreasing protein levels and reside in genes encoding homo-dimeric enzymes. These observations raise the possibility that neuropathy-associated ARS variants exert a dominant-negative effect, reducing overall ARS activity below a threshold required for peripheral nerve function. To test such variants for dominant-negative properties, we developed a humanized yeast assay to co-express pathogenic human alanyl-tRNA synthetase (AARS1) mutations with wild-type human AARS1. We show that multiple loss-of-function AARS1 mutations impair yeast growth through an interaction with wild-type AARS1, but that reducing this interaction rescues yeast growth. This suggests that neuropathy-associated AARS1 variants exert a dominant-negative effect, which supports a common, loss-of-function mechanism for ARS-mediated dominant peripheral neuropathy.
Collapse
Affiliation(s)
- Rebecca Meyer-Schuman
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Sheila Marte
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Tyler J Smith
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
| | - Shawna M E Feely
- Department of Neurology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Marina Kennerson
- Northcott Neuroscience Laboratory, ANZAC Research Institute, Sydney, NSW 2139, Australia
- Sydney Medical School, University of Sydney, Sydney, NSW 2050, Australia
- Molecular Medicine Laboratory, Concord General Repatriation Hospital, Sydney, NSW 2139, Australia
| | - Garth Nicholson
- Northcott Neuroscience Laboratory, ANZAC Research Institute, Sydney, NSW 2139, Australia
- Sydney Medical School, University of Sydney, Sydney, NSW 2050, Australia
- Molecular Medicine Laboratory, Concord General Repatriation Hospital, Sydney, NSW 2139, Australia
| | - Mike E Shy
- Department of Neurology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Kristin S Koutmou
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
| | - Anthony Antonellis
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48109, USA
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| |
Collapse
|
8
|
Kalotay E, Klugmann M, Housley GD, Fröhlich D. Dominant aminoacyl-tRNA synthetase disorders: lessons learned from in vivo disease models. Front Neurosci 2023; 17:1182845. [PMID: 37274211 PMCID: PMC10234151 DOI: 10.3389/fnins.2023.1182845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 04/05/2023] [Indexed: 06/06/2023] Open
Abstract
Aminoacyl-tRNA synthetases (ARSs) play an essential role in protein synthesis, being responsible for ligating tRNA molecules to their corresponding amino acids in a reaction known as 'tRNA aminoacylation'. Separate ARSs carry out the aminoacylation reaction in the cytosol and in mitochondria, and mutations in almost all ARS genes cause pathophysiology most evident in the nervous system. Dominant mutations in multiple cytosolic ARSs have been linked to forms of peripheral neuropathy including Charcot-Marie-Tooth disease, distal hereditary motor neuropathy, and spinal muscular atrophy. This review provides an overview of approaches that have been employed to model each of these diseases in vivo, followed by a discussion of the existing animal models of dominant ARS disorders and key mechanistic insights that they have provided. In summary, ARS disease models have demonstrated that loss of canonical ARS function alone cannot fully account for the observed disease phenotypes, and that pathogenic ARS variants cause developmental defects within the peripheral nervous system, despite a typically later onset of disease in humans. In addition, aberrant interactions between mutant ARSs and other proteins have been shown to contribute to the disease phenotypes. These findings provide a strong foundation for future research into this group of diseases, providing methodological guidance for studies on ARS disorders that currently lack in vivo models, as well as identifying candidate therapeutic targets.
Collapse
Affiliation(s)
- Elizabeth Kalotay
- Translational Neuroscience Facility and Department of Physiology, School of Biomedical Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Matthias Klugmann
- Translational Neuroscience Facility and Department of Physiology, School of Biomedical Sciences, University of New South Wales, Sydney, NSW, Australia
- Research Beyond Borders, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Germany
| | - Gary D. Housley
- Translational Neuroscience Facility and Department of Physiology, School of Biomedical Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Dominik Fröhlich
- Translational Neuroscience Facility and Department of Physiology, School of Biomedical Sciences, University of New South Wales, Sydney, NSW, Australia
| |
Collapse
|
9
|
He J, Liu XX, Ma MM, Lin JJ, Fu J, Chen YK, Xu GR, Xu LQ, Fu ZF, Xu D, Chen WF, Cao CY, Shi Y, Zeng YH, Zhang J, Chen XC, Zhang RX, Wang N, Kennerson M, Fan DS, Chen WJ. Heterozygous Seryl-tRNA Synthetase 1 Variants Cause Charcot-Marie-Tooth Disease. Ann Neurol 2023; 93:244-256. [PMID: 36088542 DOI: 10.1002/ana.26501] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 09/05/2022] [Accepted: 09/06/2022] [Indexed: 01/31/2023]
Abstract
OBJECTIVE Despite the increasing number of genes associated with Charcot-Marie-Tooth (CMT) disease, many patients currently still lack appropriate genetic diagnosis for this disease. Autosomal dominant mutations in aminoacyl-tRNA synthetases (ARSs) have been implicated in CMT. Here, we describe causal missense mutations in the gene encoding seryl-tRNA synthetase 1 (SerRS) for 3 families affected with CMT. METHODS Whole-exome sequencing was performed in 16 patients and 14 unaffected members of 3 unrelated families. The functional impact of the genetic variants identified was investigated using bioinformatic prediction tools and confirmed using cellular and biochemical assays. RESULTS Combined linkage analysis for the 3 families revealed significant linkage (Zmax LOD = 6.9) between the genomic co-ordinates on chromosome 1: 108681600-110300504. Within the linkage region, heterozygous SerRS missense variants segregated with the clinical phenotype in the 3 families. The mutant SerRS proteins exhibited reduced aminoacylation activity and abnormal SerRS dimerization, which suggests the impairment of total protein synthesis and induction of eIF2α phosphorylation. INTERPRETATION Our findings suggest the heterozygous SerRS variants identified represent a novel cause for autosomal dominant CMT. Mutant SerRS proteins are known to impact various molecular and cellular functions. Our findings provide significant advances on the current understanding of the molecular mechanisms associated with ARS-related CMT. ANN NEUROL 2023;93:244-256.
Collapse
Affiliation(s)
- Jin He
- Department of Neurology and Institute of Neurology of First Affiliated Hospital, Institute of Neuroscience, and Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Xiao-Xuan Liu
- Department of Neurology of Peking University Third Hospital, Key Laboratory for Neuroscience, National Health Commission/Ministry of Education, Peking University, Beijing, China
- Beijing Key Laboratory of Biomarker and Translational Research in Neurodegenerative Diseases, Peking University Third Hospital, Beijing, China
| | - Ming-Ming Ma
- Department of Neurology, Henan Provincial People's Hospital, Zhengzhou, China
| | - Jing-Jing Lin
- Department of Neurology and Institute of Neurology of First Affiliated Hospital, Institute of Neuroscience, and Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Jun Fu
- Department of Neurology, Henan Provincial People's Hospital, Zhengzhou, China
| | - Yi-Kun Chen
- Department of Neurology and Institute of Neurology of First Affiliated Hospital, Institute of Neuroscience, and Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Guo-Rong Xu
- Department of Neurology and Institute of Neurology of First Affiliated Hospital, Institute of Neuroscience, and Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Liu-Qing Xu
- Department of Neurology and Institute of Neurology of First Affiliated Hospital, Institute of Neuroscience, and Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Zhi-Fei Fu
- Public Technology Service Center, Fujian Medical University, Fuzhou, China
| | - Dan Xu
- Fujian Key Laboratory of Molecular Neurology, Institute of Neuroscience, Fujian Medical University, Fuzhou, China
| | - Wen-Feng Chen
- Institute of Life Sciences, College of Biological Science and Engineering, Fuzhou University, Fuzhou, China
| | - Chun-Yan Cao
- Department of Neurology and Institute of Neurology of First Affiliated Hospital, Institute of Neuroscience, and Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Yan Shi
- Fujian Key Laboratory of Molecular Neurology, Institute of Neuroscience, Fujian Medical University, Fuzhou, China
| | - Yi-Heng Zeng
- Department of Neurology and Institute of Neurology of First Affiliated Hospital, Institute of Neuroscience, and Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Jing Zhang
- Fujian Key Laboratory of Molecular Neurology, Institute of Neuroscience, Fujian Medical University, Fuzhou, China
| | - Xiao-Chun Chen
- Fujian Key Laboratory of Molecular Neurology, Institute of Neuroscience, Fujian Medical University, Fuzhou, China
| | - Ru-Xu Zhang
- Department of Neurology, Third Xiangya Hospital, Central South University, Changsha, China
| | - Ning Wang
- Department of Neurology and Institute of Neurology of First Affiliated Hospital, Institute of Neuroscience, and Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Marina Kennerson
- Northcott Neuroscience Laboratory, ANZAC Research Institute, Sydney Local Health District and Faculty of Medicine and Health, University of Sydney, Sydney, Australia
| | - Dong-Sheng Fan
- Department of Neurology of Peking University Third Hospital, Key Laboratory for Neuroscience, National Health Commission/Ministry of Education, Peking University, Beijing, China
- Beijing Key Laboratory of Biomarker and Translational Research in Neurodegenerative Diseases, Peking University Third Hospital, Beijing, China
| | - Wan-Jin Chen
- Department of Neurology and Institute of Neurology of First Affiliated Hospital, Institute of Neuroscience, and Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| |
Collapse
|
10
|
Hines TJ, Tadenev ALD, Lone MA, Hatton CL, Bagasrawala I, Stum MG, Miers KE, Hornemann T, Burgess RW. Precision mouse models of Yars/dominant intermediate Charcot-Marie-Tooth disease type C and Sptlc1/hereditary sensory and autonomic neuropathy type 1. J Anat 2022; 241:1169-1185. [PMID: 34875719 PMCID: PMC9170831 DOI: 10.1111/joa.13605] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 11/23/2021] [Accepted: 11/26/2021] [Indexed: 01/25/2023] Open
Abstract
Animal models of neurodegenerative diseases such as inherited peripheral neuropathies sometimes accurately recreate the pathophysiology of the human disease, and sometimes accurately recreate the genetic perturbations found in patients. Ideally, models achieve both, but this is not always possible; nonetheless, such models are informative. Here we describe two animal models of inherited peripheral neuropathy: mice with a mutation in tyrosyl tRNA-synthetase, YarsE196K , modeling dominant intermediate Charcot-Marie-Tooth disease type C (diCMTC), and mice with a mutation in serine palmitoyltransferase long chain 1, Sptlc1C133W , modeling hereditary sensory and autonomic neuropathy type 1 (HSAN1). YarsE196K mice develop disease-relevant phenotypes including reduced motor performance and reduced nerve conduction velocities by 4 months of age. Peripheral motor axons are reduced in size, but there is no reduction in axon number and plasma neurofilament light chain levels are not increased. Unlike the dominant human mutations, the YarsE196K mice only show these phenotypes as homozygotes, or as compound heterozygotes with a null allele, and no phenotype is observed in E196K or null heterozygotes. The Sptlc1C133W mice carry a knockin allele and show the anticipated increase in 1-deoxysphingolipids in circulation and in a variety of tissues. They also have mild behavioral defects consistent with HSAN1, but do not show neurophysiological defects or axon loss in peripheral nerves or in the epidermis of the hind paw or tail. Thus, despite the biochemical phenotype, the Sptlc1C133W mice do not show a strong neuropathy phenotype. Surprisingly, these mice were lethal as homozygotes, but the heterozygous genotype studied corresponds to the dominant genetics seen in humans. Thus, YarsE196K homozygous mice have a relevant phenotype, but imprecisely reproduce the human genetics, whereas the Sptlc1C133W mice precisely reproduce the human genetics, but do not recreate the disease phenotype. Despite these shortcomings, both models are informative and will be useful for future research.
Collapse
Affiliation(s)
| | | | - Museer A Lone
- Institute for Clinical Chemistry, University of Zurich, Zurich, Switzerland
| | | | | | | | | | - Thorsten Hornemann
- Institute for Clinical Chemistry, University of Zurich, Zurich, Switzerland
| | | |
Collapse
|
11
|
Turvey AK, Horvath GA, Cavalcanti ARO. Aminoacyl-tRNA synthetases in human health and disease. Front Physiol 2022; 13:1029218. [PMID: 36330207 PMCID: PMC9623071 DOI: 10.3389/fphys.2022.1029218] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 10/04/2022] [Indexed: 11/29/2022] Open
Abstract
The Aminoacyl-tRNA Synthetases (aaRSs) are an evolutionarily ancient family of enzymes that catalyze the esterification reaction linking a transfer RNA (tRNA) with its cognate amino acid matching the anticodon triplet of the tRNA. Proper functioning of the aaRSs to create aminoacylated (or “charged”) tRNAs is required for efficient and accurate protein synthesis. Beyond their basic canonical function in protein biosynthesis, aaRSs have a surprisingly diverse array of non-canonical functions that are actively being defined. The human genome contains 37 genes that encode unique aaRS proteins. To date, 56 human genetic diseases caused by damaging variants in aaRS genes have been described: 46 are autosomal recessive biallelic disorders and 10 are autosomal dominant monoallelic disorders. Our appreciation of human diseases caused by damaging genetic variants in the aaRSs has been greatly accelerated by the advent of next-generation sequencing, with 89% of these gene discoveries made since 2010. In addition to these genetic disorders of the aaRSs, anti-synthetase syndrome (ASSD) is a rare autoimmune inflammatory myopathy that involves the production of autoantibodies that disrupt aaRS proteins. This review provides an overview of the basic biology of aaRS proteins and describes the rapidly growing list of human diseases known to be caused by genetic variants or autoimmune targeting that affect both the canonical and non-canonical functions of these essential proteins.
Collapse
Affiliation(s)
- Alexandra K. Turvey
- Department of Biology, Pomona College, Claremont, CA, United States
- *Correspondence: Alexandra K. Turvey,
| | - Gabriella A. Horvath
- Division of Biochemical Genetics, Department of Pediatrics, University of British Columbia, BC Children’s Hospital, Vancouver, BC, Canada
- Adult Metabolic Diseases Clinic, Vancouver General Hospital, Vancouver, BC, Canada
| | | |
Collapse
|
12
|
Hyde LF, Kong Y, Zhao L, Rao SR, Wang J, Stone L, Njaa A, Collin GB, Krebs MP, Chang B, Fliesler SJ, Nishina PM, Naggert JK. A Dpagt1 Missense Variant Causes Degenerative Retinopathy without Myasthenic Syndrome in Mice. Int J Mol Sci 2022; 23:12005. [PMID: 36233305 PMCID: PMC9570038 DOI: 10.3390/ijms231912005] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 09/29/2022] [Accepted: 10/04/2022] [Indexed: 01/12/2023] Open
Abstract
Congenital disorders of glycosylation (CDG) are a heterogenous group of primarily autosomal recessive mendelian diseases caused by disruptions in the synthesis of lipid-linked oligosaccharides and their transfer to proteins. CDGs usually affect multiple organ systems and vary in presentation, even within families. There is currently no cure, and treatment is aimed at ameliorating symptoms and improving quality of life. Here, we describe a chemically induced mouse mutant, tvrm76, with early-onset photoreceptor degeneration. The recessive mutation was mapped to Chromosome 9 and associated with a missense mutation in the Dpagt1 gene encoding UDP-N-acetyl-D-glucosamine:dolichyl-phosphate N-acetyl-D-glucosaminephosphotransferase (EC 2.7.8.15). The mutation is predicted to cause a substitution of aspartic acid with glycine at residue 166 of DPAGT1. This represents the first viable animal model of a Dpagt1 mutation and a novel phenotype for a CDG. The increased expression of Ddit3, and elevated levels of HSPA5 (BiP) suggest the presence of early-onset endoplasmic reticulum (ER) stress. These changes were associated with the induction of photoreceptor apoptosis in tvrm76 retinas. Mutations in human DPAGT1 cause myasthenic syndrome-13 and severe forms of a congenital disorder of glycosylation Type Ij. In contrast, Dpagt1tvrm76 homozygous mice present with congenital photoreceptor degeneration without overt muscle or muscular junction involvement. Our results suggest the possibility of DPAGT1 mutations in human patients that present primarily with retinitis pigmentosa, with little or no muscle disease. Variants in DPAGT1 should be considered when evaluating cases of non-syndromic retinal degeneration.
Collapse
Affiliation(s)
| | - Yang Kong
- The Jackson Laboratory, Bar Harbor, ME 04609, USA
- The Graduate School of Biomedical Science and Engineering, University of Maine, Orono, ME 04469, USA
| | - Lihong Zhao
- The Jackson Laboratory, Bar Harbor, ME 04609, USA
| | - Sriganesh Ramachandra Rao
- Departments of Ophthalmology and Biochemistry and Neuroscience Graduate Program, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY 14203, USA
- Research Service, VA Western New York Healthcare System, Buffalo, NY 14215, USA
| | - Jieping Wang
- The Jackson Laboratory, Bar Harbor, ME 04609, USA
| | - Lisa Stone
- The Jackson Laboratory, Bar Harbor, ME 04609, USA
| | - Andrew Njaa
- The Jackson Laboratory, Bar Harbor, ME 04609, USA
| | | | - Mark P Krebs
- The Jackson Laboratory, Bar Harbor, ME 04609, USA
| | - Bo Chang
- The Jackson Laboratory, Bar Harbor, ME 04609, USA
| | - Steven J Fliesler
- Departments of Ophthalmology and Biochemistry and Neuroscience Graduate Program, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY 14203, USA
- Research Service, VA Western New York Healthcare System, Buffalo, NY 14215, USA
| | | | | |
Collapse
|
13
|
Polikarpova AV, Egorova TV, Bardina MV. Genetically modified animal models of hereditary diseases for testing of gene-directed therapy. RESEARCH RESULTS IN PHARMACOLOGY 2022. [DOI: 10.3897/rrpharmacology.8.82618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Disease-causing genes have been identified for many severe muscular and neurological genetic disorders. Advances in the gene therapy field offer promising solutions for drug development to treat these life-threatening conditions. Depending on how the mutation affects the function of the gene product, different gene therapy approaches may be beneficial. Gene replacement therapy is appropriate for diseases caused by mutations that result in the deficiency of the functional protein. Gene suppression strategy is suggested for disorders caused by the toxic product of the mutant gene. Splicing modulators, genome editing, and base editing techniques can be applied to disorders with different types of underlying mutations. Testing potential drugs in animal models of human diseases is an indispensable step of development. Given the specific gene therapy approach, appropriate animal models can be generated using a variety of technologies ranging from transgenesis to precise genome editing. In this review, we discuss technologies used to generate small and large animal models of the most common muscular and neurological genetic disorders. We specifically focus on animal models that were used to test gene therapies based on adeno-associated vectors and antisense nucleotides.
Collapse
|
14
|
Hines TJ, Lutz C, Murray SA, Burgess RW. An Integrated Approach to Studying Rare Neuromuscular Diseases Using Animal and Human Cell-Based Models. Front Cell Dev Biol 2022; 9:801819. [PMID: 35047510 PMCID: PMC8762301 DOI: 10.3389/fcell.2021.801819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 11/30/2021] [Indexed: 11/13/2022] Open
Abstract
As sequencing technology improves, the identification of new disease-associated genes and new alleles of known genes is rapidly increasing our understanding of the genetic underpinnings of rare diseases, including neuromuscular diseases. However, precisely because these disorders are rare and often heterogeneous, they are difficult to study in patient populations. In parallel, our ability to engineer the genomes of model organisms, such as mice or rats, has gotten increasingly efficient through techniques such as CRISPR/Cas9 genome editing, allowing the creation of precision human disease models. Such in vivo model systems provide an efficient means for exploring disease mechanisms and identifying therapeutic strategies. Furthermore, animal models provide a platform for preclinical studies to test the efficacy of those strategies. Determining whether the same mechanisms are involved in the human disease and confirming relevant parameters for treatment ideally involves a human experimental system. One system currently being used is induced pluripotent stem cells (iPSCs), which can then be differentiated into the relevant cell type(s) for in vitro confirmation of disease mechanisms and variables such as target engagement. Here we provide a demonstration of these approaches using the example of tRNA-synthetase-associated inherited peripheral neuropathies, rare forms of Charcot-Marie-Tooth disease (CMT). Mouse models have led to a better understanding of both the genetic and cellular mechanisms underlying the disease. To determine if the mechanisms are similar in human cells, we will use genetically engineered iPSC-based models. This will allow comparisons of different CMT-associated GARS alleles in the same genetic background, reducing the variability found between patient samples and simplifying the availability of cell-based models for a rare disease. The necessity of integrating mouse and human models, strategies for accomplishing this integration, and the challenges of doing it at scale are discussed using recently published work detailing the cellular mechanisms underlying GARS-associated CMT as a framework.
Collapse
|
15
|
Nam DE, Park JH, Park CE, Jung NY, Nam SH, Kwon HM, Kim HS, Kim SB, Son WS, Choi BO, Chung KW. Variants of aminoacyl-tRNA synthetase genes in Charcot-Marie-Tooth disease: A Korean cohort study. J Peripher Nerv Syst 2021; 27:38-49. [PMID: 34813128 DOI: 10.1111/jns.12476] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 10/18/2021] [Accepted: 11/18/2021] [Indexed: 01/01/2023]
Abstract
Charcot-Marie-Tooth disease (CMT) and related diseases are a genetically and clinically heterogeneous group of peripheral neuropathies. Particularly, mutations in several aminoacyl-tRNA synthetase (ARS) genes have been reported to cause axonal CMT (CMT2) or distal hereditary motor neuropathy (dHMN). However, the common pathogenesis among CMT subtypes by different ARS gene defects is not well understood. This study was performed to investigate ARS gene mutations in a CMT cohort of 710 Korean families. Whole-exome sequencing was applied to 710 CMT patients who were negative for PMP22 duplication. We identified 12 disease-causing variants (from 13 families) in GARS1, AARS1, HARS1, WARS1, and YARS1 genes. Seven variants were determined to be novel. The frequency of overall ARS gene mutations was 1.22% among all independent patients diagnosed with CMT and 1.83% in patients negative for PMP22 duplication. WARS1 mutations have been reported to cause dHMN; however, in our patients with WARS1 variants, CMT was associated with sensory involvement. We analyzed genotype-phenotype correlations and expanded the phenotypic spectrum of patients with CMT possessing ARS gene variants. We also characterized clinical phenotypes according to ARS genes. This study will be useful for performing exact molecular and clinical diagnoses and providing reference data for other population studies.
Collapse
Affiliation(s)
- Da Eun Nam
- Department of Biological Sciences, Kongju National University, Gongju, South Korea
| | - Jin Hee Park
- Department of Biological Sciences, Kongju National University, Gongju, South Korea
| | - Cho Eun Park
- Department of Biological Sciences, Kongju National University, Gongju, South Korea
| | - Na Young Jung
- Department of Biological Sciences, Kongju National University, Gongju, South Korea
| | - Soo Hyun Nam
- Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, South Korea
| | - Hye Mi Kwon
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea
| | - Hyun Su Kim
- Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea
| | - Sang Beom Kim
- Department of Neurology, Kyung Hee University Gangdong Hospital, Kyung Hee University College of Medicine, Seoul, South Korea
| | - Won Seok Son
- Department of Biological Sciences, Kongju National University, Gongju, South Korea
| | - Byung-Ok Choi
- Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, South Korea.,Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.,Stem Cell & Regenerative Medicine Institute, Samsung Medical Center, Seoul, South Korea
| | - Ki Wha Chung
- Department of Biological Sciences, Kongju National University, Gongju, South Korea
| |
Collapse
|
16
|
Ozes B, Moss K, Myers M, Ridgley A, Chen L, Murrey D, Sahenk Z. AAV1.NT-3 gene therapy in a CMT2D model: phenotypic improvements in GarsP278KY/+ mice. Brain Commun 2021; 3:fcab252. [PMID: 34755111 PMCID: PMC8568849 DOI: 10.1093/braincomms/fcab252] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 09/24/2021] [Accepted: 09/28/2021] [Indexed: 12/15/2022] Open
Abstract
Glycyl-tRNA synthetase mutations are associated to the Charcot-Marie-Tooth disease type-2D. The GarsP278KY/+ model for Charcot-Marie-Tooth disease type-2D is known best for its early onset severe neuropathic phenotype with findings including reduced axon size, slow conduction velocities and abnormal neuromuscular junction. Muscle involvement remains largely unexamined. We tested the efficacy of neurotrophin 3 gene transfer therapy in two Gars mutants with severe (GarsP278KY/+ ) and milder (GarsΔETAQ/+ ) phenotypes via intramuscular injection of adeno-associated virus setoype-1, triple tandem muscle creatine kinase promoter, neurotrophin 3 (AAV1.tMCK.NT-3) at 1 × 1011 vg dose. In the GarsP278KY/+ mice, the treatment efficacy was assessed at 12 weeks post-injection using rotarod test, electrophysiology and detailed quantitative histopathological studies of the peripheral nervous system including neuromuscular junction and muscle. Neurotrophin 3 gene transfer therapy in GarsP278KY/+ mice resulted in significant functional and electrophysiological improvements, supported with increases in myelin thickness and improvements in the denervated status of neuromuscular junctions as well as increases in muscle fibre size along with attenuation of myopathic changes. Improvements in the milder phenotype GarsΔETAQ/+ was less pronounced. Furthermore, oxidative enzyme histochemistry in muscles from Gars mutants revealed alterations in the content and distribution of oxidative enzymes with increased expression levels of Pgc1a. Cox1, Cox3 and Atp5d transcripts were significantly decreased suggesting that the muscle phenotype might be related to mitochondrial dysfunction. Neurotrophin 3 gene therapy attenuated these abnormalities in the muscle. This study shows that neurotrophin 3 gene transfer therapy has disease modifying effect in a mouse model for Charcot-Marie-Tooth disease type-2D, leading to meaningful improvements in peripheral nerve myelination and neuromuscular junction integrity as well as in a unique myopathic process, associated with mitochondria dysfunction, all in combination contributing to functional outcome. Based on the multiple biological effects of this versatile molecule, we predict neurotrophin 3 has the potential to be beneficial in other aminoacyl-tRNA synthetase-linked Charcot-Marie-Tooth disease subtypes.
Collapse
Affiliation(s)
- Burcak Ozes
- Department of Pediatrics, Center for Gene Therapy, The Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Kyle Moss
- Department of Pediatrics, Center for Gene Therapy, The Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Morgan Myers
- Department of Pediatrics, Center for Gene Therapy, The Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Alicia Ridgley
- Department of Pediatrics, Center for Gene Therapy, The Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Lei Chen
- Department of Pediatrics, Center for Gene Therapy, The Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Darren Murrey
- Department of Pediatrics, Center for Gene Therapy, The Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Zarife Sahenk
- Department of Pediatrics, Center for Gene Therapy, The Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, OH 43205, USA.,Department of Pediatrics and Neurology, Nationwide Children's Hospital and The Ohio State University, Columbus, OH 43205, USA.,Department of Pathology and Laboratory Medicine, Nationwide Children's Hospital, Columbus, OH 43205, USA
| |
Collapse
|
17
|
Mendonsa S, von Kuegelgen N, Bujanic L, Chekulaeva M. Charcot-Marie-Tooth mutation in glycyl-tRNA synthetase stalls ribosomes in a pre-accommodation state and activates integrated stress response. Nucleic Acids Res 2021; 49:10007-10017. [PMID: 34403468 PMCID: PMC8464049 DOI: 10.1093/nar/gkab730] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 08/12/2021] [Indexed: 11/14/2022] Open
Abstract
Toxic gain-of-function mutations in aminoacyl-tRNA synthetases cause a degeneration of peripheral motor and sensory axons, known as Charcot–Marie–Tooth (CMT) disease. While these mutations do not disrupt overall aminoacylation activity, they interfere with translation via an unknown mechanism. Here, we dissect the mechanism of function of CMT mutant glycyl-tRNA synthetase (CMT-GARS), using high-resolution ribosome profiling and reporter assays. We find that CMT-GARS mutants deplete the pool of glycyl-tRNAGly available for translation and inhibit the first stage of elongation, the accommodation of glycyl-tRNA into the ribosomal A-site, which causes ribosomes to pause at glycine codons. Moreover, ribosome pausing activates a secondary repression mechanism at the level of translation initiation, by inducing the phosphorylation of the alpha subunit of eIF2 and the integrated stress response. Thus, CMT-GARS mutant triggers translational repression via two interconnected mechanisms, affecting both elongation and initiation of translation.
Collapse
Affiliation(s)
- Samantha Mendonsa
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany.,Free University, Berlin, Germany
| | - Nicolai von Kuegelgen
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany.,Free University, Berlin, Germany
| | - Lucija Bujanic
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Marina Chekulaeva
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| |
Collapse
|
18
|
Spaulding EL, Hines TJ, Bais P, Tadenev ALD, Schneider R, Jewett D, Pattavina B, Pratt SL, Morelli KH, Stum MG, Hill DP, Gobet C, Pipis M, Reilly MM, Jennings MJ, Horvath R, Bai Y, Shy ME, Alvarez-Castelao B, Schuman EM, Bogdanik LP, Storkebaum E, Burgess RW. The integrated stress response contributes to tRNA synthetase-associated peripheral neuropathy. Science 2021; 373:1156-1161. [PMID: 34516839 PMCID: PMC8908546 DOI: 10.1126/science.abb3414] [Citation(s) in RCA: 66] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Dominant mutations in ubiquitously expressed transfer RNA (tRNA) synthetase genes cause axonal peripheral neuropathy, accounting for at least six forms of Charcot-Marie-Tooth (CMT) disease. Genetic evidence in mouse and Drosophila models suggests a gain-of-function mechanism. In this study, we used in vivo, cell type–specific transcriptional and translational profiling to show that mutant tRNA synthetases activate the integrated stress response (ISR) through the sensor kinase GCN2 (general control nonderepressible 2). The chronic activation of the ISR contributed to the pathophysiology, and genetic deletion or pharmacological inhibition of Gcn2 alleviated the peripheral neuropathy. The activation of GCN2 suggests that the aberrant activity of the mutant tRNA synthetases is still related to translation and that inhibiting GCN2 or the ISR may represent a therapeutic strategy in CMT.
Collapse
Affiliation(s)
- E. L. Spaulding
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA
- Graduate School of Biomedical Science and Engineering, University of Maine, Orono, ME 04469, USA
| | - T. J. Hines
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA
| | - P. Bais
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA
| | - A. L. D. Tadenev
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA
| | - R. Schneider
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA
| | - D. Jewett
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA
| | - B. Pattavina
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA
| | - S. L. Pratt
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA
- Neuroscience Program, Graduate School of Biomedical Sciences, Tufts University, Boston, MA, 02111 USA
| | - K. H. Morelli
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA
- Graduate School of Biomedical Science and Engineering, University of Maine, Orono, ME 04469, USA
| | - M. G. Stum
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA
| | - D. P. Hill
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA
| | - C. Gobet
- School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - M. Pipis
- MRC Centre for Neuromuscular Diseases, Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, UK
| | - M. M. Reilly
- MRC Centre for Neuromuscular Diseases, Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, UK
| | - M. J. Jennings
- Department of Clinical Neuroscience, University of Cambridge, Cambridge, UK
| | - R. Horvath
- Department of Clinical Neuroscience, University of Cambridge, Cambridge, UK
| | - Y. Bai
- Department of Neurology, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | - M. E. Shy
- Department of Neurology, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | | | - E. M. Schuman
- Max Planck Institute for Brain Research, Frankfurt, Germany
| | - L. P. Bogdanik
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA
| | - E. Storkebaum
- Department of Molecular Neurobiology, Donders Institute for Brain, Cognition and Behaviour and Faculty of Science, Radboud University, Nijmegen, Netherlands
| | - R. W. Burgess
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA
- Graduate School of Biomedical Science and Engineering, University of Maine, Orono, ME 04469, USA
- Neuroscience Program, Graduate School of Biomedical Sciences, Tufts University, Boston, MA, 02111 USA
| |
Collapse
|
19
|
Zuko A, Mallik M, Thompson R, Spaulding EL, Wienand AR, Been M, Tadenev ALD, van Bakel N, Sijlmans C, Santos LA, Bussmann J, Catinozzi M, Das S, Kulshrestha D, Burgess RW, Ignatova Z, Storkebaum E. tRNA overexpression rescues peripheral neuropathy caused by mutations in tRNA synthetase. Science 2021; 373:1161-1166. [PMID: 34516840 DOI: 10.1126/science.abb3356] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
[Figure: see text].
Collapse
Affiliation(s)
- Amila Zuko
- Department of Molecular Neurobiology, Donders Institute for Brain, Cognition and Behaviour and Faculty of Science, Radboud University, Nijmegen, Netherlands
| | - Moushami Mallik
- Department of Molecular Neurobiology, Donders Institute for Brain, Cognition and Behaviour and Faculty of Science, Radboud University, Nijmegen, Netherlands.,Molecular Neurogenetics Laboratory, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| | - Robin Thompson
- Biochemistry and Molecular Biology, Department of Chemistry, University of Hamburg, Hamburg, Germany
| | - Emily L Spaulding
- The Jackson Laboratory, Bar Harbor, ME, USA.,Graduate School of Biomedical Sciences and Engineering, University of Maine, Orono, ME, USA
| | - Anne R Wienand
- Department of Molecular Neurobiology, Donders Institute for Brain, Cognition and Behaviour and Faculty of Science, Radboud University, Nijmegen, Netherlands
| | - Marije Been
- Department of Molecular Neurobiology, Donders Institute for Brain, Cognition and Behaviour and Faculty of Science, Radboud University, Nijmegen, Netherlands
| | | | - Nick van Bakel
- Department of Molecular Neurobiology, Donders Institute for Brain, Cognition and Behaviour and Faculty of Science, Radboud University, Nijmegen, Netherlands
| | - Céline Sijlmans
- Department of Molecular Neurobiology, Donders Institute for Brain, Cognition and Behaviour and Faculty of Science, Radboud University, Nijmegen, Netherlands
| | - Leonardo A Santos
- Biochemistry and Molecular Biology, Department of Chemistry, University of Hamburg, Hamburg, Germany
| | - Julia Bussmann
- Molecular Neurogenetics Laboratory, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| | - Marica Catinozzi
- Department of Molecular Neurobiology, Donders Institute for Brain, Cognition and Behaviour and Faculty of Science, Radboud University, Nijmegen, Netherlands.,Molecular Neurogenetics Laboratory, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| | - Sarada Das
- Biochemistry and Molecular Biology, Department of Chemistry, University of Hamburg, Hamburg, Germany
| | - Divita Kulshrestha
- Department of Molecular Neurobiology, Donders Institute for Brain, Cognition and Behaviour and Faculty of Science, Radboud University, Nijmegen, Netherlands.,Molecular Neurogenetics Laboratory, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| | - Robert W Burgess
- The Jackson Laboratory, Bar Harbor, ME, USA.,Graduate School of Biomedical Sciences and Engineering, University of Maine, Orono, ME, USA
| | - Zoya Ignatova
- Biochemistry and Molecular Biology, Department of Chemistry, University of Hamburg, Hamburg, Germany
| | - Erik Storkebaum
- Department of Molecular Neurobiology, Donders Institute for Brain, Cognition and Behaviour and Faculty of Science, Radboud University, Nijmegen, Netherlands.,Molecular Neurogenetics Laboratory, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| |
Collapse
|
20
|
Stavrou M, Sargiannidou I, Georgiou E, Kagiava A, Kleopa KA. Emerging Therapies for Charcot-Marie-Tooth Inherited Neuropathies. Int J Mol Sci 2021; 22:6048. [PMID: 34205075 PMCID: PMC8199910 DOI: 10.3390/ijms22116048] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 05/29/2021] [Accepted: 05/31/2021] [Indexed: 12/12/2022] Open
Abstract
Inherited neuropathies known as Charcot-Marie-Tooth (CMT) disease are genetically heterogeneous disorders affecting the peripheral nerves, causing significant and slowly progressive disability over the lifespan. The discovery of their diverse molecular genetic mechanisms over the past three decades has provided the basis for developing a wide range of therapeutics, leading to an exciting era of finding treatments for this, until now, incurable group of diseases. Many treatment approaches, including gene silencing and gene replacement therapies, as well as small molecule treatments are currently in preclinical testing while several have also reached clinical trial stage. Some of the treatment approaches are disease-specific targeted to the unique disease mechanism of each CMT form, while other therapeutics target common pathways shared by several or all CMT types. As promising treatments reach the stage of clinical translation, optimal outcome measures, novel biomarkers and appropriate trial designs are crucial in order to facilitate successful testing and validation of novel treatments for CMT patients.
Collapse
Affiliation(s)
- Marina Stavrou
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics, Cyprus School of Molecular Medicine, Nicosia 2371, Cyprus; (M.S.); (I.S.); (E.G.); (A.K.)
| | - Irene Sargiannidou
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics, Cyprus School of Molecular Medicine, Nicosia 2371, Cyprus; (M.S.); (I.S.); (E.G.); (A.K.)
| | - Elena Georgiou
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics, Cyprus School of Molecular Medicine, Nicosia 2371, Cyprus; (M.S.); (I.S.); (E.G.); (A.K.)
| | - Alexia Kagiava
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics, Cyprus School of Molecular Medicine, Nicosia 2371, Cyprus; (M.S.); (I.S.); (E.G.); (A.K.)
| | - Kleopas A. Kleopa
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics, Cyprus School of Molecular Medicine, Nicosia 2371, Cyprus; (M.S.); (I.S.); (E.G.); (A.K.)
- Center for Neuromuscular Diseases, The Cyprus Institute of Neurology and Genetics, Cyprus School of Molecular Medicine, Nicosia 2371, Cyprus
| |
Collapse
|
21
|
Zhao Y, Xie L, Shen C, Qi Q, Qin Y, Xing J, Zhou D, Qi Y, Yan Z, Lin X, Dai R, Lin J, Yu W. SIRT2-knockdown rescues GARS-induced Charcot-Marie-Tooth neuropathy. Aging Cell 2021; 20:e13391. [PMID: 34053152 PMCID: PMC8208790 DOI: 10.1111/acel.13391] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 04/10/2021] [Accepted: 05/08/2021] [Indexed: 12/18/2022] Open
Abstract
Charcot‐Marie‐Tooth disease is the most common inherited peripheral neuropathy. Dominant mutations in the glycyl‐tRNA synthetase (GARS) gene cause peripheral nerve degeneration and lead to CMT disease type 2D. The underlying mechanisms of mutations in GARS (GARSCMT2D) in disease pathogenesis are not fully understood. In this study, we report that wild‐type GARS binds the NAD+‐dependent deacetylase SIRT2 and inhibits its deacetylation activity, resulting in the acetylated α‐tubulin, the major substrate of SIRT2. The catalytic domain of GARS tightly interacts with SIRT2, which is the most CMT2D mutation localization. However, CMT2D mutations in GARS cannot inhibit SIRT2 deacetylation, which leads to a decrease of acetylated α‐tubulin. Genetic reduction of SIRT2 in the Drosophila model rescues the GARS‐induced axonal CMT neuropathy and extends the life span. Our findings demonstrate the pathogenic role of SIRT2‐dependent α‐tubulin deacetylation in mutant GARS‐induced neuropathies and provide new perspectives for targeting SIRT2 as a potential therapy against hereditary axonopathies.
Collapse
Affiliation(s)
- Yingying Zhao
- State Key Laboratory of Genetic Engineering School of Life Sciences Zhongshan Hospital Fudan University Shanghai China
| | - Liangguo Xie
- State Key Laboratory of Genetic Engineering School of Life Sciences Zhongshan Hospital Fudan University Shanghai China
| | - Chao Shen
- State Key Laboratory of Genetic Engineering School of Life Sciences Zhongshan Hospital Fudan University Shanghai China
| | - Qian Qi
- State Key Laboratory of Genetic Engineering School of Life Sciences Zhongshan Hospital Fudan University Shanghai China
| | - Yicai Qin
- State Key Laboratory of Genetic Engineering School of Life Sciences Zhongshan Hospital Fudan University Shanghai China
| | - Juan Xing
- School of Basic Medical Science Southwest Medical University Luzhou China
| | - Dejian Zhou
- State Key Laboratory of Genetic Engineering School of Life Sciences Zhongshan Hospital Fudan University Shanghai China
| | - Yun Qi
- State Key Laboratory of Genetic Engineering School of Life Sciences Zhongshan Hospital Fudan University Shanghai China
| | - Zhiqiang Yan
- State Key Laboratory of Genetic Engineering School of Life Sciences Zhongshan Hospital Fudan University Shanghai China
| | - Xinhua Lin
- State Key Laboratory of Genetic Engineering School of Life Sciences Zhongshan Hospital Fudan University Shanghai China
| | - Rongyang Dai
- School of Basic Medical Science Southwest Medical University Luzhou China
| | - Jinzhong Lin
- State Key Laboratory of Genetic Engineering School of Life Sciences Zhongshan Hospital Fudan University Shanghai China
| | - Wei Yu
- State Key Laboratory of Genetic Engineering School of Life Sciences Zhongshan Hospital Fudan University Shanghai China
- School of Basic Medical Science Southwest Medical University Luzhou China
| |
Collapse
|
22
|
Vinogradova ES, Nikonov OS, Nikonova EY. Associations between Neurological Diseases and Mutations in the Human Glycyl-tRNA Synthetase. BIOCHEMISTRY (MOSCOW) 2021; 86:S12-S23. [PMID: 33827397 PMCID: PMC7905983 DOI: 10.1134/s0006297921140029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Aminoacyl-RNA synthetases (aaRSs) are among the key enzymes of protein biosynthesis. They are responsible for conducting the first step in the protein biosynthesis, namely attaching amino acids to the corresponding tRNA molecules both in cytoplasm and mitochondria. More and more research demonstrates that mutations in the genes encoding aaRSs lead to the development of various neurodegenerative diseases, such as incurable Charcot–Marie–Tooth disease (CMT) and distal spinal muscular atrophy. Some mutations result in the loss of tRNA aminoacylation activity, while other mutants retain their classical enzyme activity. In the latter case, disease manifestations are associated with additional neuron-specific functions of aaRSs. At present, seven aaRSs (GlyRS, TyrRS, AlaRS, HisRS, TrpRS, MetRS, and LysRS) are known to be involved in the CMT etiology with glycyl-tRNA synthetase (GlyRS) being the most studied of them.
Collapse
Affiliation(s)
| | - Oleg S Nikonov
- Institute of Protein Research, Pushchino, Moscow Region, 142290, Russia
| | | |
Collapse
|
23
|
Structural analyses of a human lysyl-tRNA synthetase mutant associated with autosomal recessive nonsyndromic hearing impairment. Biochem Biophys Res Commun 2021; 554:83-88. [PMID: 33784510 DOI: 10.1016/j.bbrc.2021.03.093] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 03/17/2021] [Indexed: 11/22/2022]
Abstract
Aminoacyl-tRNA synthetases (AARSs) catalyze the ligation of amino acids to their cognate tRNAs and therefore play an essential role in protein biosynthesis in all living cells. The KARS gene in human encodes both cytosolic and mitochondrial lysyl-tRNA synthetase (LysRS). A recent study identified a missense mutation in KARS gene (c.517T > C) that caused autosomal recessive nonsyndromic hearing loss. This mutation led to a tyrosine to histidine (YH) substitution in both cytosolic and mitochondrial LysRS proteins, and decreased their aminoacylation activity to different levels. Here, we report the crystal structure of LysRS YH mutant at a resolution of 2.5 Å. We found that the mutation did not interfere with the active center, nor did it cause any significant conformational changes in the protein. The loops involved in tetramer interface and tRNA anticodon binding site showed relatively bigger variations between the mutant and wild type proteins. Considering the differences between the cytosolic and mitochondrial tRNAlyss, we suggest that the mutation triggered subtle changes in the tRNA anticodon binding region, and the interferences were further amplified by the different D and T loops in mitochondrial tRNAlys, and led to a complete loss of the aminoacylation of mitochondrial tRNAlys.
Collapse
|
24
|
Abstract
Charcot-Marie-Tooth disease (CMT) is a devastating motor and sensory neuropathy with an estimated 100,000 afflicted individuals in the US. Unexpectedly, aminoacyl-tRNA synthetases are the largest disease-associated protein family. A natural explanation is that the disease is associated with weak translation or mistranslation (caused by editing defects). However, our results with six different disease-causing mutants in AlaRS ruled out defects in aminoacylation or editing as causal factors. Instead, specific mutant proteins gained a neuropilin 1 (Nrp1)-AlaRS interaction. Previously a gain of Nrp1 interaction with a different disease-causing tRNA synthetase was mechanistically linked to the pathology of CMT. Thus, our results raise the possibility that pathological engagement of Nrp1 is common to at least a subset of tRNA synthetase-associated cases of CMT. Through dominant mutations, aminoacyl-tRNA synthetases constitute the largest protein family linked to Charcot-Marie-Tooth disease (CMT). An example is CMT subtype 2N (CMT2N), caused by individual mutations spread out in AlaRS, including three in the aminoacylation domain, thereby suggesting a role for a tRNA-charging defect. However, here we found that two are aminoacylation defective but that the most widely distributed R329H is normal as a purified protein in vitro and in unfractionated patient cell samples. Remarkably, in contrast to wild-type (WT) AlaRS, all three mutant proteins gained the ability to interact with neuropilin 1 (Nrp1), the receptor previously linked to CMT pathogenesis in GlyRS. The aberrant AlaRS-Nrp1 interaction is further confirmed in patient samples carrying the R329H mutation. However, CMT2N mutations outside the aminoacylation domain do not induce the Nrp1 interaction. Detailed biochemical and biophysical investigations, including X-ray crystallography, small-angle X-ray scattering, hydrogen-deuterium exchange (HDX), switchSENSE hydrodynamic diameter determinations, and protease digestions reveal a mutation-induced structural loosening of the aminoacylation domain that correlates with the Nrp1 interaction. The b1b2 domains of Nrp1 are responsible for the interaction with R329H AlaRS. The results suggest Nrp1 is more broadly associated with CMT-associated members of the tRNA synthetase family. Moreover, we revealed a distinct structural loosening effect induced by a mutation in the editing domain and a lack of conformational impact with C-Ala domain mutations, indicating mutations in the same protein may cause neuropathy through different mechanisms. Our results show that, as with other CMT-associated tRNA synthetases, aminoacylation per se is not relevant to the pathology.
Collapse
|
25
|
Schiavon CR, Shadel GS, Manor U. Impaired Mitochondrial Mobility in Charcot-Marie-Tooth Disease. Front Cell Dev Biol 2021; 9:624823. [PMID: 33598463 PMCID: PMC7882694 DOI: 10.3389/fcell.2021.624823] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Accepted: 01/05/2021] [Indexed: 12/13/2022] Open
Abstract
Charcot-Marie-Tooth (CMT) disease is a progressive, peripheral neuropathy and the most commonly inherited neurological disorder. Clinical manifestations of CMT mutations are typically limited to peripheral neurons, the longest cells in the body. Currently, mutations in at least 80 different genes are associated with CMT and new mutations are regularly being discovered. A large portion of the proteins mutated in axonal CMT have documented roles in mitochondrial mobility, suggesting that organelle trafficking defects may be a common underlying disease mechanism. This review will focus on the potential role of altered mitochondrial mobility in the pathogenesis of axonal CMT, highlighting the conceptional challenges and potential experimental and therapeutic opportunities presented by this "impaired mobility" model of the disease.
Collapse
Affiliation(s)
- Cara R. Schiavon
- Waitt Advanced Biophotonics Center, Salk Institute for Biological Studies, La Jolla, CA, United States
- Molecular and Cell Biology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, United States
| | - Gerald S. Shadel
- Molecular and Cell Biology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, United States
| | - Uri Manor
- Waitt Advanced Biophotonics Center, Salk Institute for Biological Studies, La Jolla, CA, United States
| |
Collapse
|
26
|
Zhang H, Zhou ZW, Sun L. Aminoacyl-tRNA synthetases in Charcot-Marie-Tooth disease: A gain or a loss? J Neurochem 2020; 157:351-369. [PMID: 33236345 PMCID: PMC8247414 DOI: 10.1111/jnc.15249] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 11/17/2020] [Accepted: 11/19/2020] [Indexed: 01/05/2023]
Abstract
Charcot‐Marie‐Tooth disease (CMT) is one of the most common inherited neurodegenerative disorders with an increasing number of CMT‐associated variants identified as causative factors, however, there has been no effective therapy for CMT to date. Aminoacyl‐tRNA synthetases (aaRS) are essential enzymes in translation by charging amino acids onto their cognate tRNAs during protein synthesis. Dominant monoallelic variants of aaRSs have been largely implicated in CMT. Some aaRSs variants affect enzymatic activity, demonstrating a loss‐of‐function property. In contrast, loss of aminoacylation activity is neither necessary nor sufficient for some aaRSs variants to cause CMT. Instead, accumulating evidence from CMT patient samples, animal genetic studies or protein conformational analysis has pinpointed toxic gain‐of‐function of aaRSs variants in CMT, suggesting complicated mechanisms underlying the pathogenesis of CMT. In this review, we summarize the latest advances in studies on CMT‐linked aaRSs, with a particular focus on their functions. The current challenges, future direction and the promising candidates for potential treatment of CMT are also discussed. ![]()
Collapse
Affiliation(s)
- Han Zhang
- Institute of Medical Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Kunming, China
| | - Zhong-Wei Zhou
- School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Litao Sun
- School of Public Health (Shenzhen), Sun Yat-sen University, Guangzhou, China
| |
Collapse
|
27
|
Miressi F, Magdelaine C, Cintas P, Bourthoumieux S, Nizou A, Derouault P, Favreau F, Sturtz F, Faye PA, Lia AS. One Multilocus Genomic Variation Is Responsible for a Severe Charcot-Marie-Tooth Axonal Form. Brain Sci 2020; 10:brainsci10120986. [PMID: 33333791 PMCID: PMC7765239 DOI: 10.3390/brainsci10120986] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 12/06/2020] [Accepted: 12/09/2020] [Indexed: 12/17/2022] Open
Abstract
Charcot-Marie-Tooth (CMT) disease is a heterogeneous group of inherited disorders affecting the peripheral nervous system, with a prevalence of 1/2500. So far, mutations in more than 80 genes have been identified causing either demyelinating forms (CMT1) or axonal forms (CMT2). Consequentially, the genotype-phenotype correlation is not always easy to assess. Diagnosis could require multiple analysis before the correct causative mutation is detected. Moreover, it seems that approximately 5% of overall diagnoses for genetic diseases involves multiple genomic loci, although they are often underestimated or underreported. In particular, the combination of multiple variants is rarely described in CMT pathology and often neglected during the diagnostic process. Here, we present the complex genetic analysis of a family including two CMT cases with various severities. Interestingly, next generation sequencing (NGS) associated with Cov'Cop analysis, allowing structural variants (SV) detection, highlighted variations in MORC2 (microrchidia family CW-type zinc-finger 2) and AARS1 (alanyl-tRNA-synthetase) genes for one patient and an additional mutation in MFN2 (Mitofusin 2) in the more affected patient.
Collapse
Affiliation(s)
- Federica Miressi
- Maintenance Myélinique et Neuropathies Périphériques, Université de Limoges, EA 6309, F-87000 Limoges, France; (C.M.); (S.B.); (A.N.); (F.F.); (F.S.); (P.-A.F.); (A.-S.L.)
- Correspondence:
| | - Corinne Magdelaine
- Maintenance Myélinique et Neuropathies Périphériques, Université de Limoges, EA 6309, F-87000 Limoges, France; (C.M.); (S.B.); (A.N.); (F.F.); (F.S.); (P.-A.F.); (A.-S.L.)
- Service de Biochimie et Génétique Moléculaire, Centre Hospitalier Universitaire à Limoges, F-87000 Limoges, France
| | - Pascal Cintas
- Service de Neurologie, Centre Hospitalier Universitaire à Toulouse, F-31000 Toulouse, France;
| | - Sylvie Bourthoumieux
- Maintenance Myélinique et Neuropathies Périphériques, Université de Limoges, EA 6309, F-87000 Limoges, France; (C.M.); (S.B.); (A.N.); (F.F.); (F.S.); (P.-A.F.); (A.-S.L.)
- Service de Cytogénétique, Centre Hospitalier Universitaire à Limoges, F-87000 Limoges, France
| | - Angélique Nizou
- Maintenance Myélinique et Neuropathies Périphériques, Université de Limoges, EA 6309, F-87000 Limoges, France; (C.M.); (S.B.); (A.N.); (F.F.); (F.S.); (P.-A.F.); (A.-S.L.)
| | - Paco Derouault
- Service de Bioinformatique, Centre Hospitalier Universitaire à Limoges, F-87000 Limoges, France;
| | - Frédéric Favreau
- Maintenance Myélinique et Neuropathies Périphériques, Université de Limoges, EA 6309, F-87000 Limoges, France; (C.M.); (S.B.); (A.N.); (F.F.); (F.S.); (P.-A.F.); (A.-S.L.)
- Service de Biochimie et Génétique Moléculaire, Centre Hospitalier Universitaire à Limoges, F-87000 Limoges, France
| | - Franck Sturtz
- Maintenance Myélinique et Neuropathies Périphériques, Université de Limoges, EA 6309, F-87000 Limoges, France; (C.M.); (S.B.); (A.N.); (F.F.); (F.S.); (P.-A.F.); (A.-S.L.)
- Service de Biochimie et Génétique Moléculaire, Centre Hospitalier Universitaire à Limoges, F-87000 Limoges, France
| | - Pierre-Antoine Faye
- Maintenance Myélinique et Neuropathies Périphériques, Université de Limoges, EA 6309, F-87000 Limoges, France; (C.M.); (S.B.); (A.N.); (F.F.); (F.S.); (P.-A.F.); (A.-S.L.)
- Service de Biochimie et Génétique Moléculaire, Centre Hospitalier Universitaire à Limoges, F-87000 Limoges, France
| | - Anne-Sophie Lia
- Maintenance Myélinique et Neuropathies Périphériques, Université de Limoges, EA 6309, F-87000 Limoges, France; (C.M.); (S.B.); (A.N.); (F.F.); (F.S.); (P.-A.F.); (A.-S.L.)
- Service de Biochimie et Génétique Moléculaire, Centre Hospitalier Universitaire à Limoges, F-87000 Limoges, France
- Service de Bioinformatique, Centre Hospitalier Universitaire à Limoges, F-87000 Limoges, France;
| |
Collapse
|
28
|
Forrester N, Rattihalli R, Horvath R, Maggi L, Manzur A, Fuller G, Gutowski N, Rankin J, Dick D, Buxton C, Greenslade M, Majumdar A. Clinical and Genetic Features in a Series of Eight Unrelated Patients with Neuropathy Due to Glycyl-tRNA Synthetase (GARS) Variants. J Neuromuscul Dis 2020; 7:137-143. [PMID: 31985473 DOI: 10.3233/jnd-200472] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Pathogenic variants in the Glycyl-tRNA synthetase gene cause the allelic disorders Charcot-Marie-Tooth disease type 2D and distal hereditary motor neuropathy type V. We describe clinical features in 8 unrelated patients found to have Glycyl-tRNA synthetase variants by Next Generation Sequencing. In addition to upper limb predominant symptoms, other presentations included failure to thrive, feeding difficulties and lower limb dominant symptoms. Variability in the age at testing ranged from 14 months to 59 years. The youngest being symptomatic from 3 months and ventilator-dependent. Sequence variants were reported as pathogenic, p.(Glu125Lys), p.(His472Arg); likely pathogenic, p.(His216Arg), p.(Gly327Arg), p.(Lys510Gln), p.(Met555Val); and of uncertain significance, p.(Arg27Pro). Our case series describes novel Glycyl-tRNA synthetase variants and demonstrates the clinical utility of Next Generation Sequencing testing for patients with hereditary neuropathy. Identification of novel variants by Next Generation Sequencing illustrates that there exists a wide spectrum of clinical features and supports the newer simplified classification of neuropathies.
Collapse
Affiliation(s)
| | - Rohini Rattihalli
- John Radcliffe Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Rita Horvath
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
| | | | - Adnan Manzur
- Dubowitz Neuromuscular Centre, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Geraint Fuller
- Gloucester Royal Infirmary, Gloucestershire Hospitals NHS Foundation Trust, Gloucester, UK
| | - Nicholas Gutowski
- Peninsula Clinical Genetics, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
| | - Julia Rankin
- Peninsula Clinical Genetics, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
| | - David Dick
- Norfolk and Norwich University Hospital, Norwich, UK
| | | | - Mark Greenslade
- Bristol Genetics Laboratory, North Bristol Trust, Bristol, UK
| | | |
Collapse
|
29
|
Sleigh JN, Mech AM, Aktar T, Zhang Y, Schiavo G. Altered Sensory Neuron Development in CMT2D Mice Is Site-Specific and Linked to Increased GlyRS Levels. Front Cell Neurosci 2020; 14:232. [PMID: 32848623 PMCID: PMC7431706 DOI: 10.3389/fncel.2020.00232] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 07/01/2020] [Indexed: 12/18/2022] Open
Abstract
Dominant, missense mutations in the widely and constitutively expressed GARS1 gene cause peripheral neuropathy that usually begins in adolescence and principally impacts the upper limbs. Caused by a toxic gain-of-function in the encoded glycyl-tRNA synthetase (GlyRS) enzyme, the neuropathology appears to be independent of the canonical role of GlyRS in aminoacylation. Patients display progressive, life-long weakness and wasting of muscles in hands followed by feet, with frequently associated deficits in sensation. When dysfunction is observed in motor and sensory nerves, there is a diagnosis of Charcot-Marie-Tooth disease type 2D (CMT2D), or distal hereditary motor neuropathy type V if the symptoms are purely motor. The cause of this varied sensory involvement remains unresolved, as are the pathomechanisms underlying the selective neurodegeneration characteristic of the disease. We have previously identified in CMT2D mice that neuropathy-causing Gars mutations perturb sensory neuron fate and permit mutant GlyRS to aberrantly interact with neurotrophin receptors (Trks). Here, we extend this work by interrogating further the anatomy and function of the CMT2D sensory nervous system in mutant Gars mice, obtaining several key results: (1) sensory pathology is restricted to neurons innervating the hindlimbs; (2) perturbation of sensory development is not common to all mouse models of neuromuscular disease; (3) in vitro axonal transport of signaling endosomes is not impaired in afferent neurons of all CMT2D mouse models; and (4) Gars expression is selectively elevated in a subset of sensory neurons and linked to sensory developmental defects. These findings highlight the importance of comparative neurological assessment in mouse models of disease and shed light on key proposed neuropathogenic mechanisms in GARS1-linked neuropathy.
Collapse
Affiliation(s)
- James N. Sleigh
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
- UK Dementia Research Institute, University College London, London, United Kingdom
| | - Aleksandra M. Mech
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Tahmina Aktar
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Yuxin Zhang
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Giampietro Schiavo
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
- UK Dementia Research Institute, University College London, London, United Kingdom
- Discoveries Centre for Regenerative and Precision Medicine, University College London Campus, London, United Kingdom
| |
Collapse
|
30
|
Sleigh JN, Mech AM, Schiavo G. Developmental demands contribute to early neuromuscular degeneration in CMT2D mice. Cell Death Dis 2020; 11:564. [PMID: 32703932 PMCID: PMC7378196 DOI: 10.1038/s41419-020-02798-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 07/10/2020] [Accepted: 07/13/2020] [Indexed: 12/13/2022]
Abstract
Dominantly inherited, missense mutations in the widely expressed housekeeping gene, GARS1, cause Charcot-Marie-Tooth type 2D (CMT2D), a peripheral neuropathy characterised by muscle weakness and wasting in limb extremities. Mice modelling CMT2D display early and selective neuromuscular junction (NMJ) pathology, epitomised by disturbed maturation and neurotransmission, leading to denervation. Indeed, the NMJ disruption has been reported in several different muscles; however, a systematic comparison of neuromuscular synapses from distinct body locations has yet to be performed. We therefore analysed NMJ development and degeneration across five different wholemount muscles to identify key synaptic features contributing to the distinct pattern of neurodegeneration in CMT2D mice. Denervation was found to occur along a distal-to-proximal gradient, providing a cellular explanation for the greater weakness observed in mutant Gars hindlimbs compared with forelimbs. Nonetheless, muscles from similar locations and innervated by axons of equivalent length showed significant differences in neuropathology, suggestive of additional factors impacting on site-specific neuromuscular degeneration. Defective NMJ development preceded and associated with degeneration, but was not linked to a delay of wild-type NMJ maturation processes. Correlation analyses indicate that muscle fibre type nor synaptic architecture explain the differential denervation of CMT2D NMJs, rather it is the extent of post-natal synaptic growth that predisposes to neurodegeneration. Together, this work improves our understanding of the mechanisms driving synaptic vulnerability in CMT2D and hints at pertinent pathogenic pathways.
Collapse
Affiliation(s)
- James N Sleigh
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK.
- UK Dementia Research Institute, University College London, London, WC1E 6BT, UK.
| | - Aleksandra M Mech
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK
| | - Giampietro Schiavo
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK
- UK Dementia Research Institute, University College London, London, WC1E 6BT, UK
- Discoveries Centre for Regenerative and Precision Medicine, University College London Campus, London, WC1N 3BG, UK
| |
Collapse
|
31
|
Morelli KH, Griffin LB, Pyne NK, Wallace LM, Fowler AM, Oprescu SN, Takase R, Wei N, Meyer-Schuman R, Mellacheruvu D, Kitzman JO, Kocen SG, Hines TJ, Spaulding EL, Lupski JR, Nesvizhskii A, Mancias P, Butler IJ, Yang XL, Hou YM, Antonellis A, Harper SQ, Burgess RW. Allele-specific RNA interference prevents neuropathy in Charcot-Marie-Tooth disease type 2D mouse models. J Clin Invest 2020; 129:5568-5583. [PMID: 31557132 DOI: 10.1172/jci130600] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 09/10/2019] [Indexed: 12/24/2022] Open
Abstract
Gene therapy approaches are being deployed to treat recessive genetic disorders by restoring the expression of mutated genes. However, the feasibility of these approaches for dominantly inherited diseases - where treatment may require reduction in the expression of a toxic mutant protein resulting from a gain-of-function allele - is unclear. Here we show the efficacy of allele-specific RNAi as a potential therapy for Charcot-Marie-Tooth disease type 2D (CMT2D), caused by dominant mutations in glycyl-tRNA synthetase (GARS). A de novo mutation in GARS was identified in a patient with a severe peripheral neuropathy, and a mouse model precisely recreating the mutation was produced. These mice developed a neuropathy by 3-4 weeks of age, validating the pathogenicity of the mutation. RNAi sequences targeting mutant GARS mRNA, but not wild-type, were optimized and then packaged into AAV9 for in vivo delivery. This almost completely prevented the neuropathy in mice treated at birth. Delaying treatment until after disease onset showed modest benefit, though this effect decreased the longer treatment was delayed. These outcomes were reproduced in a second mouse model of CMT2D using a vector specifically targeting that allele. The effects were dose dependent, and persisted for at least 1 year. Our findings demonstrate the feasibility of AAV9-mediated allele-specific knockdown and provide proof of concept for gene therapy approaches for dominant neuromuscular diseases.
Collapse
Affiliation(s)
- Kathryn H Morelli
- The Jackson Laboratory, Bar Harbor, Maine, USA.,Graduate School of Biomedical Science and Engineering, University of Maine, Orono, Maine, USA
| | - Laurie B Griffin
- Program in Cellular and Molecular Biology, and.,Medical Scientist Training Program, University of Michigan, Ann Arbor, Michigan, USA
| | - Nettie K Pyne
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Lindsay M Wallace
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Allison M Fowler
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Stephanie N Oprescu
- Department of Human Genetics, University of Michigan, Ann Arbor, Michigan, USA
| | - Ryuichi Takase
- Department of Biochemistry and Molecular Biochemistry, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Na Wei
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, USA
| | | | - Dattatreya Mellacheruvu
- Department of Pathology, and.,Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, Michigan, USA
| | - Jacob O Kitzman
- Department of Human Genetics, University of Michigan, Ann Arbor, Michigan, USA
| | | | | | - Emily L Spaulding
- The Jackson Laboratory, Bar Harbor, Maine, USA.,Graduate School of Biomedical Science and Engineering, University of Maine, Orono, Maine, USA
| | - James R Lupski
- Department of Molecular and Human Genetics, and.,Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA.,Texas Children's Hospital, Houston, Texas, USA
| | - Alexey Nesvizhskii
- Department of Pathology, and.,Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, Michigan, USA
| | - Pedro Mancias
- Department of Pediatrics, McGovern Medical School, The University of Texas Health Science Center at Houston, and Children's Memorial Hermann Hospital, Houston, Texas, USA
| | - Ian J Butler
- Department of Pediatrics, McGovern Medical School, The University of Texas Health Science Center at Houston, and Children's Memorial Hermann Hospital, Houston, Texas, USA
| | - Xiang-Lei Yang
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, USA
| | - Ya-Ming Hou
- Department of Biochemistry and Molecular Biochemistry, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Anthony Antonellis
- Program in Cellular and Molecular Biology, and.,Department of Human Genetics, University of Michigan, Ann Arbor, Michigan, USA
| | - Scott Q Harper
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA.,Department of Pediatrics, The Ohio State University College of Medicine, Columbus, Ohio, USA
| | - Robert W Burgess
- The Jackson Laboratory, Bar Harbor, Maine, USA.,Graduate School of Biomedical Science and Engineering, University of Maine, Orono, Maine, USA
| |
Collapse
|
32
|
McFarland MR, Keller CD, Childers BM, Adeniyi SA, Corrigall H, Raguin A, Romano MC, Stansfield I. The molecular aetiology of tRNA synthetase depletion: induction of a GCN4 amino acid starvation response despite homeostatic maintenance of charged tRNA levels. Nucleic Acids Res 2020; 48:3071-3088. [PMID: 32016368 PMCID: PMC7102972 DOI: 10.1093/nar/gkaa055] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 01/16/2020] [Accepted: 01/18/2020] [Indexed: 12/13/2022] Open
Abstract
During protein synthesis, charged tRNAs deliver amino acids to translating ribosomes, and are then re-charged by tRNA synthetases (aaRS). In humans, mutant aaRS cause a diversity of neurological disorders, but their molecular aetiologies are incompletely characterised. To understand system responses to aaRS depletion, the yeast glutamine aaRS gene (GLN4) was transcriptionally regulated using doxycycline by tet-off control. Depletion of Gln4p inhibited growth, and induced a GCN4 amino acid starvation response, indicative of uncharged tRNA accumulation and Gcn2 kinase activation. Using a global model of translation that included aaRS recharging, Gln4p depletion was simulated, confirming slowed translation. Modelling also revealed that Gln4p depletion causes negative feedback that matches translational demand for Gln-tRNAGln to aaRS recharging capacity. This maintains normal charged tRNAGln levels despite Gln4p depletion, confirmed experimentally using tRNA Northern blotting. Model analysis resolves the paradox that Gln4p depletion triggers a GCN4 response, despite maintenance of tRNAGln charging levels, revealing that normally, the aaRS population can sequester free, uncharged tRNAs during aminoacylation. Gln4p depletion reduces this sequestration capacity, allowing uncharged tRNAGln to interact with Gcn2 kinase. The study sheds new light on mutant aaRS disease aetiologies, and explains how aaRS sequestration of uncharged tRNAs can prevent GCN4 activation under non-starvation conditions.
Collapse
Affiliation(s)
- Matthew R McFarland
- Institute of Medical Sciences, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, AB25 2ZD, UK
| | - Corina D Keller
- Institute of Complex Systems and Mathematical Biology, University of Aberdeen, Aberdeen, AB24 3UE, UK
| | - Brandon M Childers
- Institute of Medical Sciences, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, AB25 2ZD, UK
| | - Stephen A Adeniyi
- Institute of Medical Sciences, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, AB25 2ZD, UK
| | - Holly Corrigall
- Institute of Medical Sciences, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, AB25 2ZD, UK
| | - Adélaïde Raguin
- Institute of Complex Systems and Mathematical Biology, University of Aberdeen, Aberdeen, AB24 3UE, UK
| | - M Carmen Romano
- Institute of Complex Systems and Mathematical Biology, University of Aberdeen, Aberdeen, AB24 3UE, UK
| | - Ian Stansfield
- Institute of Medical Sciences, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, AB25 2ZD, UK
| |
Collapse
|
33
|
Ravi B, Antonellis A, Sumner CJ, Lieberman AP. Genetic approaches to the treatment of inherited neuromuscular diseases. Hum Mol Genet 2020; 28:R55-R64. [PMID: 31227836 DOI: 10.1093/hmg/ddz131] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 04/29/2019] [Accepted: 06/07/2019] [Indexed: 12/17/2022] Open
Abstract
Inherited neuromuscular diseases are a heterogeneous group of developmental and degenerative disorders that affect motor unit function. Major challenges toward developing therapies for these diseases include heterogeneity with respect to clinical severity, age of onset and the primary cell type that is affected (e.g. motor neurons, skeletal muscle and Schwann cells). Here, we review recent progress toward the establishment of genetic therapies to treat inherited neuromuscular disorders that affect both children and adults with a focus on spinal muscular atrophy, Charcot-Marie-Tooth disease and spinal and bulbar muscular atrophy. We discuss clinical features, causative mutations and emerging approaches that are undergoing testing in preclinical models and in patients or that have received recent approval for clinical use. Many of these efforts employ antisense oligonucleotides to alter pre-mRNA splicing or diminish target gene expression and use viral vectors to replace expression of mutant genes. Finally, we discuss remaining challenges for optimizing the delivery and effectiveness of these approaches. In sum, therapeutic strategies for neuromuscular diseases have shown encouraging results, raising hope that recent strides will translate into significant clinical benefits for patients with these disorders.
Collapse
Affiliation(s)
- Bhavya Ravi
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Anthony Antonellis
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI, USA
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Charlotte J Sumner
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Andrew P Lieberman
- Department of Pathology, University of Michigan Medical School, Ann Arbor, MI, USA
| |
Collapse
|
34
|
Morelli KH, Hatton CL, Harper SQ, Burgess RW. Gene therapies for axonal neuropathies: Available strategies, successes to date, and what to target next. Brain Res 2020; 1732:146683. [PMID: 32001243 DOI: 10.1016/j.brainres.2020.146683] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 01/23/2020] [Accepted: 01/24/2020] [Indexed: 12/20/2022]
Abstract
Nearly one-hundred loci in the human genome have been associated with different forms of Charcot-Marie-Tooth disease (CMT) and related inherited neuropathies. Despite this wealth of gene targets, treatment options are still extremely limited, and clear "druggable" pathways are not obvious for many of these mutations. However, recent advances in gene therapies are beginning to circumvent this challenge. Each type of CMT is a monogenic disorder, and the cellular targets are usually well-defined and typically include peripheral neurons or Schwann cells. In addition, the genetic mechanism is often also clear, with loss-of-function mutations requiring restoration of gene expression, and gain-of-function or dominant-negative mutations requiring silencing of the mutant allele. These factors combine to make CMT a good target for developing genetic therapies. Here we will review the state of relatively established gene therapy approaches, including viral vector-mediated gene replacement and antisense oligonucleotides for exon skipping, altering splicing, and gene knockdown. We will also describe earlier stage approaches for allele-specific knockdown and CRIPSR/Cas9 gene editing. We will next describe how these various approaches have been deployed in clinical and preclinical studies. Finally, we will evaluate various forms of CMT as candidates for gene therapy based on the current understanding of their genetics, cellular/tissue targets, validated animal models, and availability of patient populations and natural history data.
Collapse
Affiliation(s)
- Kathryn H Morelli
- The Jackson Laboratory, Bar Harbor, ME 04609, USA; The Graduate School of Biomedical Science and Engineering, University of Maine, Orono, ME 04469, USA
| | | | - Scott Q Harper
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, OH, USA; Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, USA
| | - Robert W Burgess
- The Jackson Laboratory, Bar Harbor, ME 04609, USA; The Graduate School of Biomedical Science and Engineering, University of Maine, Orono, ME 04469, USA.
| |
Collapse
|
35
|
Martin PB, Hicks AN, Holbrook SE, Cox GA. Overlapping spectrums: The clinicogenetic commonalities between Charcot-Marie-Tooth and other neurodegenerative diseases. Brain Res 2020; 1727:146532. [PMID: 31678418 PMCID: PMC6939129 DOI: 10.1016/j.brainres.2019.146532] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 10/20/2019] [Accepted: 10/22/2019] [Indexed: 12/11/2022]
Abstract
Charcot-Marie-Tooth (CMT) disease is a progressive and heterogeneous inherited peripheral neuropathy. A myriad of genetic factors have been identified that contribute to the degeneration of motor and sensory axons in a length-dependent manner. Emerging biological themes underlying disease include defects in axonal trafficking, dysfunction in RNA metabolism and protein homeostasis, as well deficits in the cellular stress response. Moreover, genetic contributions to CMT can have overlap with other neuropathies, motor neuron diseases (MNDs) and neurodegenerative disorders. Recent progress in understanding the molecular biology of CMT and overlapping syndromes aids in the search for necessary therapeutic targets.
Collapse
Affiliation(s)
- Paige B Martin
- The Jackson Laboratory, Bar Harbor, ME 04609, USA; Graduate School of Biomedical Sciences and Engineering, University of Maine, Orono, ME 04469, USA
| | - Amy N Hicks
- The Jackson Laboratory, Bar Harbor, ME 04609, USA
| | - Sarah E Holbrook
- The Jackson Laboratory, Bar Harbor, ME 04609, USA; Graduate School of Biomedical Sciences and Engineering, University of Maine, Orono, ME 04469, USA
| | - Gregory A Cox
- The Jackson Laboratory, Bar Harbor, ME 04609, USA; Graduate School of Biomedical Sciences and Engineering, University of Maine, Orono, ME 04469, USA.
| |
Collapse
|
36
|
Kuo ME, Antonellis A. Ubiquitously Expressed Proteins and Restricted Phenotypes: Exploring Cell-Specific Sensitivities to Impaired tRNA Charging. Trends Genet 2019; 36:105-117. [PMID: 31839378 DOI: 10.1016/j.tig.2019.11.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 11/17/2019] [Accepted: 11/18/2019] [Indexed: 12/17/2022]
Abstract
Aminoacyl-tRNA synthetases (ARS) are ubiquitously expressed, essential enzymes that charge tRNA with cognate amino acids. Variants in genes encoding ARS enzymes lead to myriad human inherited diseases. First, missense alleles cause dominant peripheral neuropathy. Second, missense, nonsense, and frameshift alleles cause recessive multisystem disorders that differentially affect tissues depending on which ARS is mutated. A preponderance of evidence has shown that both phenotypic classes are associated with loss-of-function alleles, suggesting that tRNA charging plays a central role in disease pathogenesis. However, it is currently unclear how perturbation in the function of these ubiquitously expressed enzymes leads to tissue-specific or tissue-predominant phenotypes. Here, we review our current understanding of ARS-associated disease phenotypes and discuss potential explanations for the observed tissue specificity.
Collapse
Affiliation(s)
- Molly E Kuo
- Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, MI, USA; Medical Scientist Training Program, University of Michigan, Ann Arbor, MI, USA
| | - Anthony Antonellis
- Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, MI, USA; Department of Human Genetics, University of Michigan, Ann Arbor, MI, USA; Department of Neurology, University of Michigan, Ann Arbor, MI, USA.
| |
Collapse
|
37
|
Transcriptional dysregulation by a nucleus-localized aminoacyl-tRNA synthetase associated with Charcot-Marie-Tooth neuropathy. Nat Commun 2019; 10:5045. [PMID: 31695036 PMCID: PMC6834567 DOI: 10.1038/s41467-019-12909-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 10/01/2019] [Indexed: 12/02/2022] Open
Abstract
Charcot-Marie-Tooth disease (CMT) is a length-dependent peripheral neuropathy. The aminoacyl-tRNA synthetases constitute the largest protein family implicated in CMT. Aminoacyl-tRNA synthetases are predominantly cytoplasmic, but are also present in the nucleus. Here we show that a nuclear function of tyrosyl-tRNA synthetase (TyrRS) is implicated in a Drosophila model of CMT. CMT-causing mutations in TyrRS induce unique conformational changes, which confer capacity for aberrant interactions with transcriptional regulators in the nucleus, leading to transcription factor E2F1 hyperactivation. Using neuronal tissues, we reveal a broad transcriptional regulation network associated with wild-type TyrRS expression, which is disturbed when a CMT-mutant is expressed. Pharmacological inhibition of TyrRS nuclear entry with embelin reduces, whereas genetic nuclear exclusion of mutant TyrRS prevents hallmark phenotypes of CMT in the Drosophila model. These data highlight that this translation factor may contribute to transcriptional regulation in neurons, and suggest a therapeutic strategy for CMT. Tyrosyl-tRNA synthetase (TyrRS) is a translation factor and predominantly cytoplasmic, but can also be found in the nucleus. Here authors show using a fly model of Charcot-Marie-Tooth (CMT) disease that nuclear localization of mutant TyrRS contributes to the CMT-like phenotype.
Collapse
|
38
|
CMT disease severity correlates with mutation-induced open conformation of histidyl-tRNA synthetase, not aminoacylation loss, in patient cells. Proc Natl Acad Sci U S A 2019; 116:19440-19448. [PMID: 31501329 DOI: 10.1073/pnas.1908288116] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Aminoacyl-transfer RNA (tRNA) synthetases (aaRSs) are the largest protein family causatively linked to neurodegenerative Charcot-Marie-Tooth (CMT) disease. Dominant mutations cause the disease, and studies of CMT disease-causing mutant glycyl-tRNA synthetase (GlyRS) and tyrosyl-tRNA synthetase (TyrRS) showed their mutations create neomorphic structures consistent with a gain-of-function mechanism. In contrast, based on a haploid yeast model, loss of aminoacylation function was reported for CMT disease mutants in histidyl-tRNA synthetase (HisRS). However, neither that nor prior work of any CMT disease-causing aaRS investigated the aminoacylation status of tRNAs in the cellular milieu of actual patients. Using an assay that interrogated aminoacylation levels in patient cells, we investigated a HisRS-linked CMT disease family with the most severe disease phenotype. Strikingly, no difference in charged tRNA levels between normal and diseased family members was found. In confirmation, recombinant versions of 4 other HisRS CMT disease-causing mutants showed no correlation between activity loss in vitro and severity of phenotype in vivo. Indeed, a mutation having the most detrimental impact on activity was associated with a mild disease phenotype. In further work, using 3 independent biophysical analyses, structural opening (relaxation) of mutant HisRSs at the dimer interface best correlated with disease severity. In fact, the HisRS mutation in the severely afflicted patient family caused the largest degree of structural relaxation. These data suggest that HisRS-linked CMT disease arises from open conformation-induced mechanisms distinct from loss of aminoacylation.
Collapse
|
39
|
Yalcouyé A, Diallo SH, Coulibaly T, Cissé L, Diallo S, Samassékou O, Diarra S, Coulibaly D, Keita M, Guinto CO, Fischbeck K, Landouré G. A novel mutation in the GARS gene in a Malian family with Charcot-Marie-Tooth disease. Mol Genet Genomic Med 2019; 7:e00782. [PMID: 31173493 PMCID: PMC6625146 DOI: 10.1002/mgg3.782] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Revised: 05/08/2019] [Accepted: 05/16/2019] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Charcot-Marie-Tooth (CMT) disease is a very heterogeneous neurological condition with more than 90 reported genetic entities. It is the most common inherited peripheral neuropathy; however, cases are rarely reported in sub-Saharan Africa. In addition, only few families, mostly of Caucasian ancestry, have been reported to have Charcot-Marie-Tooth disease type 2D (CMT2D) mutations. To date no case of CMT2D was reported in Africa. We present here a consanguineous family with CMT phenotype in which a novel mutation in the GARS (glycyl-tRNA synthetase) gene was identified. METHODS Patients were examined thoroughly and nerve conduction studies (NCS) were performed. DNA from the proband was used for CMT gene panel testing (including 50 genes, PMP22 duplication and mtDNA). Putative mutations were verified in all available family members to check for segregation. RESULTS Two individuals, a male and a female, were found to be affected. Symptoms started in their teenage years with muscle weakness and atrophy in hands. Later, distal involvement of the lower limbs was noticed. Patients complained of minor sensory impairment. NCS showed no response in the upper as well as the lower limbs. Genetic testing surprisingly identified a novel heterozygous missense mutation c.794C>A (p.Ser265Tyr) in the GARS gene associated with CMT2D. This variant segregated with the disease in the family and was also seen in the mother who presented no symptoms. CONCLUSION This is the first report of a genetically confirmed CMT2D case in Africa, expanding its genetic epidemiology. Increasing access to genetic testing may reveal more novel CMT variants or genes in the African population that could be relevant to other populations and further our understanding of their mechanism.
Collapse
Affiliation(s)
| | - Seybou H Diallo
- Faculté de Médecine et d'Odontostomatologie, USTTB, Bamako, Mali
- Service de Neurologie, Centre Hospitalier Universitaire Gabriel Touré, Bamako, Mali
| | - Thomas Coulibaly
- Faculté de Médecine et d'Odontostomatologie, USTTB, Bamako, Mali
- Service de Neurologie, Centre Hospitalier Universitaire du Point "G", Bamako, Mali
| | - Lassana Cissé
- Service de Neurologie, Centre Hospitalier Universitaire du Point "G", Bamako, Mali
| | - Salimata Diallo
- Service de Neurologie, Centre Hospitalier Universitaire Gabriel Touré, Bamako, Mali
| | - Oumar Samassékou
- Faculté de Médecine et d'Odontostomatologie, USTTB, Bamako, Mali
| | - Salimata Diarra
- Faculté de Médecine et d'Odontostomatologie, USTTB, Bamako, Mali
- Neurogenetics Branch, National Institutes of Neurological Disorders and Stroke, Bethesda, MD
| | - Dramane Coulibaly
- Service de Médecine, Centre Hospitalier Universitaire Mère-Enfant le "Luxembourg", Bamako, Mali
| | - Mohamed Keita
- Faculté de Médecine et d'Odontostomatologie, USTTB, Bamako, Mali
- Service d'ORL, Centre Hospitalier Universitaire Gabriel Touré, Bamako, Mali
| | - Cheick O Guinto
- Faculté de Médecine et d'Odontostomatologie, USTTB, Bamako, Mali
- Service de Neurologie, Centre Hospitalier Universitaire du Point "G", Bamako, Mali
| | - Kenneth Fischbeck
- Neurogenetics Branch, National Institutes of Neurological Disorders and Stroke, Bethesda, MD
| | - Guida Landouré
- Faculté de Médecine et d'Odontostomatologie, USTTB, Bamako, Mali
- Service de Neurologie, Centre Hospitalier Universitaire du Point "G", Bamako, Mali
- Neurogenetics Branch, National Institutes of Neurological Disorders and Stroke, Bethesda, MD
| |
Collapse
|
40
|
Benoy V, Van Helleputte L, Prior R, d'Ydewalle C, Haeck W, Geens N, Scheveneels W, Schevenels B, Cader MZ, Talbot K, Kozikowski AP, Vanden Berghe P, Van Damme P, Robberecht W, Van Den Bosch L. HDAC6 is a therapeutic target in mutant GARS-induced Charcot-Marie-Tooth disease. Brain 2019; 141:673-687. [PMID: 29415205 PMCID: PMC5837793 DOI: 10.1093/brain/awx375] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 11/20/2017] [Indexed: 01/01/2023] Open
Abstract
Peripheral nerve axons require a well-organized axonal microtubule network for efficient transport to ensure the constant crosstalk between soma and synapse. Mutations in more than 80 different genes cause Charcot-Marie-Tooth disease, which is the most common inherited disorder affecting peripheral nerves. This genetic heterogeneity has hampered the development of therapeutics for Charcot-Marie-Tooth disease. The aim of this study was to explore whether histone deacetylase 6 (HDAC6) can serve as a therapeutic target focusing on the mutant glycyl-tRNA synthetase (GlyRS/GARS)-induced peripheral neuropathy. Peripheral nerves and dorsal root ganglia from the C201R mutant Gars mouse model showed reduced acetylated α-tubulin levels. In primary dorsal root ganglion neurons, mutant GlyRS affected neurite length and disrupted normal mitochondrial transport. We demonstrated that GlyRS co-immunoprecipitated with HDAC6 and that this interaction was blocked by tubastatin A, a selective inhibitor of the deacetylating function of HDAC6. Moreover, HDAC6 inhibition restored mitochondrial axonal transport in mutant GlyRS-expressing neurons. Systemic delivery of a specific HDAC6 inhibitor increased α-tubulin acetylation in peripheral nerves and partially restored nerve conduction and motor behaviour in mutant Gars mice. Our study demonstrates that α-tubulin deacetylation and disrupted axonal transport may represent a common pathogenic mechanism underlying Charcot-Marie-Tooth disease and it broadens the therapeutic potential of selective HDAC6 inhibition to other genetic forms of axonal Charcot-Marie-Tooth disease.
Collapse
Affiliation(s)
- Veronick Benoy
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Research Institute for Neuroscience & Disease (LIND), Leuven, Belgium.,VIB - Center for Brain and Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - Lawrence Van Helleputte
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Research Institute for Neuroscience & Disease (LIND), Leuven, Belgium.,VIB - Center for Brain and Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - Robert Prior
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Research Institute for Neuroscience & Disease (LIND), Leuven, Belgium.,VIB - Center for Brain and Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - Constantin d'Ydewalle
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Research Institute for Neuroscience & Disease (LIND), Leuven, Belgium.,VIB - Center for Brain and Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - Wanda Haeck
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Research Institute for Neuroscience & Disease (LIND), Leuven, Belgium.,VIB - Center for Brain and Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - Natasja Geens
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Research Institute for Neuroscience & Disease (LIND), Leuven, Belgium.,VIB - Center for Brain and Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - Wendy Scheveneels
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Research Institute for Neuroscience & Disease (LIND), Leuven, Belgium.,VIB - Center for Brain and Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - Begga Schevenels
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Research Institute for Neuroscience & Disease (LIND), Leuven, Belgium.,VIB - Center for Brain and Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - M Zameel Cader
- Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, UK.,The Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Kevin Talbot
- Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Alan P Kozikowski
- Department of Medicinal Chemistry and Pharmacognosy, Drug Discovery Program, University of Illinois at Chicago, Chicago, USA
| | - Pieter Vanden Berghe
- Translational Research Center for Gastrointestinal Disorders, University of Leuven, Leuven, Belgium
| | - Philip Van Damme
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Research Institute for Neuroscience & Disease (LIND), Leuven, Belgium.,VIB - Center for Brain and Disease Research, Laboratory of Neurobiology, Leuven, Belgium.,University Hospitals Leuven, Department of Neurology, Leuven, Belgium
| | - Wim Robberecht
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Research Institute for Neuroscience & Disease (LIND), Leuven, Belgium.,VIB - Center for Brain and Disease Research, Laboratory of Neurobiology, Leuven, Belgium.,University Hospitals Leuven, Department of Neurology, Leuven, Belgium
| | - Ludo Van Den Bosch
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Research Institute for Neuroscience & Disease (LIND), Leuven, Belgium.,VIB - Center for Brain and Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| |
Collapse
|
41
|
Weterman MAJ, Kuo M, Kenter SB, Gordillo S, Karjosukarso DW, Takase R, Bronk M, Oprescu S, van Ruissen F, Witteveen RJW, Bienfait HME, Breuning M, Verhamme C, Hou YM, de Visser M, Antonellis A, Baas F. Hypermorphic and hypomorphic AARS alleles in patients with CMT2N expand clinical and molecular heterogeneities. Hum Mol Genet 2019; 27:4036-4050. [PMID: 30124830 DOI: 10.1093/hmg/ddy290] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 08/04/2018] [Indexed: 01/08/2023] Open
Abstract
Aminoacyl-tRNA synthetases (ARSs) are ubiquitously expressed enzymes implicated in several dominant and recessive disease phenotypes. The canonical function of ARSs is to couple an amino acid to a cognate transfer RNA (tRNA). We identified three novel disease-associated missense mutations in the alanyl-tRNA synthetase (AARS) gene in three families with dominant axonal Charcot-Marie-Tooth (CMT) disease. Two mutations (p.Arg326Trp and p.Glu337Lys) are located near a recurrent pathologic change in AARS, p.Arg329His. The third (p.Ser627Leu) is in the editing domain of the protein in which hitherto only mutations associated with recessive encephalopathies have been described. Yeast complementation assays demonstrated that two mutations (p.Ser627Leu and p.Arg326Trp) represent loss-of-function alleles, while the third (p.Glu337Lys) represents a hypermorphic allele. Further, aminoacylation assays confirmed that the third mutation (p.Glu337Lys) increases tRNA charging velocity. To test the effect of each mutation in the context of a vertebrate nervous system, we developed a zebrafish assay. Remarkably, all three mutations caused a pathological phenotype of neural abnormalities when expressed in zebrafish, while expression of the human wild-type messenger RNA (mRNA) did not. Our data indicate that not only functional null or hypomorphic alleles, but also hypermorphic AARS alleles can cause dominantly inherited axonal CMT disease.
Collapse
Affiliation(s)
- Marian A J Weterman
- Department of Clinical Genetics, Leiden University Medical Center, Leiden, Netherlands
| | - Molly Kuo
- Cellular and Molecular Biology Program, University of Michigan Medical School, Ann Arbor, MI, USA.,Medical Scientist Training Program, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Susan B Kenter
- Department of Clinical Genetics and Genome Analysis, Academic Medical Center, Amsterdam, Netherlands
| | - Sara Gordillo
- Department of Clinical Genetics and Genome Analysis, Academic Medical Center, Amsterdam, Netherlands
| | - Dyah W Karjosukarso
- Department of Clinical Genetics and Genome Analysis, Academic Medical Center, Amsterdam, Netherlands
| | - Ryuichi Takase
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, USA
| | - Marieke Bronk
- Department of Clinical Genetics and Genome Analysis, Academic Medical Center, Amsterdam, Netherlands
| | - Stephanie Oprescu
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Fred van Ruissen
- Department of Clinical Genetics and Genome Analysis, Academic Medical Center, Amsterdam, Netherlands
| | | | | | - Martijn Breuning
- Department of Clinical Genetics, Leiden University Medical Center, Leiden, Netherlands
| | - Camiel Verhamme
- Department of Neurology, Academic Medical Center, Amsterdam, Netherlands
| | - Ya-Ming Hou
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, USA
| | - Marianne de Visser
- Department of Neurology, Academic Medical Center, Amsterdam, Netherlands
| | - Anthony Antonellis
- Cellular and Molecular Biology Program, University of Michigan Medical School, Ann Arbor, MI, USA.,Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI, USA.,Department of Neurology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Frank Baas
- Department of Clinical Genetics, Leiden University Medical Center, Leiden, Netherlands
| |
Collapse
|
42
|
Corcia P, Brulard C, Beltran S, Marouillat S, Bakkouche SE, Andres CR, Blasco H, Vourc'h P. Typical bulbar ALS can be linked to GARS mutation. Amyotroph Lateral Scler Frontotemporal Degener 2019; 20:275-277. [PMID: 30661401 DOI: 10.1080/21678421.2018.1556699] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Background: Amyotrophic lateral sclerosis is the most frequent motor neuron disorders (MND) in adults. The role of genetic factors is worldwide accepted, and currently, more than 30 genes have been linked to this disease. Genetics was also the matter of numerous studies in distal hereditary motor neuropathies (dHMN). GARS is classically linked to a predominant dHMN and, until now, no mutation has been described in GARS in other MND. Case Report: We report the case of a 70-year-old woman who developed a classical bulbar ALS phenotype. Owing to his familial history of ALS, a genetic screening was performed excluding the main genes linked to ALS and revealing a heterozygous missense mutation in GARS gene with a high probability of pathogenicity. Conclusion: This first description of mutation in GARS in ALS, extends once more the genetic overlap between ALS and other MND.
Collapse
Affiliation(s)
- P Corcia
- a ALS Reference Centre, CHU de Tours.,b Federation of the ALS Center of Tours and Limoges.,c Inserm Unit U1253, Tours University , Inserm , Tours , France and
| | - C Brulard
- c Inserm Unit U1253, Tours University , Inserm , Tours , France and
| | - S Beltran
- a ALS Reference Centre, CHU de Tours.,b Federation of the ALS Center of Tours and Limoges.,c Inserm Unit U1253, Tours University , Inserm , Tours , France and
| | - S Marouillat
- c Inserm Unit U1253, Tours University , Inserm , Tours , France and
| | | | - C R Andres
- c Inserm Unit U1253, Tours University , Inserm , Tours , France and.,d Department of Biochemistry and Molecular Biology , CHU de Tours , France
| | - H Blasco
- c Inserm Unit U1253, Tours University , Inserm , Tours , France and.,d Department of Biochemistry and Molecular Biology , CHU de Tours , France
| | - P Vourc'h
- c Inserm Unit U1253, Tours University , Inserm , Tours , France and.,d Department of Biochemistry and Molecular Biology , CHU de Tours , France
| |
Collapse
|
43
|
Wei N, Zhang Q, Yang XL. Neurodegenerative Charcot-Marie-Tooth disease as a case study to decipher novel functions of aminoacyl-tRNA synthetases. J Biol Chem 2019; 294:5321-5339. [PMID: 30643024 DOI: 10.1074/jbc.rev118.002955] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Aminoacyl-tRNA synthetases (aaRSs) are essential enzymes that catalyze the first reaction in protein biosynthesis, namely the charging of transfer RNAs (tRNAs) with their cognate amino acids. aaRSs have been increasingly implicated in dominantly and recessively inherited human diseases. The most common aaRS-associated monogenic disorder is the incurable neurodegenerative disease Charcot-Marie-Tooth neuropathy (CMT), caused by dominant mono-allelic mutations in aaRSs. With six currently known members (GlyRS, TyrRS, AlaRS, HisRS, TrpRS, and MetRS), aaRSs represent the largest protein family implicated in CMT etiology. After the initial discovery linking aaRSs to CMT, the field has progressed from understanding whether impaired tRNA charging is a critical component of this disease to elucidating the specific pathways affected by CMT-causing mutations in aaRSs. Although many aaRS CMT mutants result in loss of tRNA aminoacylation function, animal genetics studies demonstrated that dominant mutations in GlyRS cause CMT through toxic gain-of-function effects, which also may apply to other aaRS-linked CMT subtypes. The CMT-causing mechanism is likely to be multifactorial and involves multiple cellular compartments, including the nucleus and the extracellular space, where the normal WT enzymes also appear. Thus, the association of aaRSs with neuropathy is relevant to discoveries indicating that aaRSs also have nonenzymatic regulatory functions that coordinate protein synthesis with other biological processes. Through genetic, functional, and structural analyses, commonalities among different mutations and different aaRS-linked CMT subtypes have begun to emerge, providing insights into the nonenzymatic functions of aaRSs and the pathogenesis of aaRS-linked CMT to guide therapeutic development to treat this disease.
Collapse
Affiliation(s)
- Na Wei
- From the Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California 92037
| | - Qian Zhang
- From the Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California 92037
| | - Xiang-Lei Yang
- From the Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California 92037
| |
Collapse
|
44
|
Shorrock HK, van der Hoorn D, Boyd PJ, Llavero Hurtado M, Lamont DJ, Wirth B, Sleigh JN, Schiavo G, Wishart TM, Groen EJN, Gillingwater TH. UBA1/GARS-dependent pathways drive sensory-motor connectivity defects in spinal muscular atrophy. Brain 2018; 141:2878-2894. [PMID: 30239612 PMCID: PMC6158753 DOI: 10.1093/brain/awy237] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 07/25/2018] [Indexed: 01/09/2023] Open
Abstract
Deafferentation of motor neurons as a result of defective sensory-motor connectivity is a critical early event in the pathogenesis of spinal muscular atrophy, but the underlying molecular pathways remain unknown. We show that restoration of ubiquitin-like modifier-activating enzyme 1 (UBA1) was sufficient to correct sensory-motor connectivity in the spinal cord of mice with spinal muscular atrophy. Aminoacyl-tRNA synthetases, including GARS, were identified as downstream targets of UBA1. Regulation of GARS by UBA1 occurred via a non-canonical pathway independent of ubiquitylation. Dysregulation of UBA1/GARS pathways in spinal muscular atrophy mice disrupted sensory neuron fate, phenocopying GARS-dependent defects associated with Charcot-Marie-Tooth disease. Sensory neuron fate was corrected following restoration of UBA1 expression and UBA1/GARS pathways in spinal muscular atrophy mice. We conclude that defective sensory motor connectivity in spinal muscular atrophy results from perturbations in a UBA1/GARS pathway that modulates sensory neuron fate, thereby highlighting significant molecular and phenotypic overlap between spinal muscular atrophy and Charcot-Marie-Tooth disease.
Collapse
Affiliation(s)
- Hannah K Shorrock
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK, Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Edinburgh, UK,Present address: Department of Molecular Genetics and Microbiology, Center for NeuroGenetics, University of Florida, 2033 Mowry Road, Gainesville, FL 32610, USA
| | - Dinja van der Hoorn
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK, Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Edinburgh, UK
| | - Penelope J Boyd
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK, Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Edinburgh, UK,Present address: Norwich Medical School, University of East Anglia, Norwich Research Park, Norwich, UK
| | - Maica Llavero Hurtado
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK, Roslin Institute, Royal (Dick) School of Veterinary Science, University of Edinburgh, UK
| | | | - Brunhilde Wirth
- Institute of Human Genetics, Center for Molecular Medicine Cologne, Institute for Genetics and Center for Rare Diseases Cologne, University of Cologne, Germany
| | - James N Sleigh
- Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London, UK
| | - Giampietro Schiavo
- Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London, UK, Discoveries Centre for Regenerative and Precision Medicine, University College London Campus, London, UK, UK Dementia Research Institute at UCL, London, UK
| | - Thomas M Wishart
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK, Roslin Institute, Royal (Dick) School of Veterinary Science, University of Edinburgh, UK
| | - Ewout J N Groen
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK, Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Edinburgh, UK,Correspondence may also be addressed to: Ewout J. N. Groen E-mail:
| | - Thomas H Gillingwater
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK, Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Edinburgh, UK,Correspondence to: Thomas H. Gillingwater University of Edinburgh - Biomedical Sciences (Anatomy) Hugh Robson Building George Square Edinburgh, Scotland EH8 9XD, UK E-mail:
| |
Collapse
|
45
|
Surrey V, Zöller C, Lork AA, Moradi M, Balk S, Dombert B, Saal-Bauernschubert L, Briese M, Appenzeller S, Fischer U, Jablonka S. Impaired Local Translation of β-actin mRNA in Ighmbp2-Deficient Motoneurons: Implications for Spinal Muscular Atrophy with respiratory Distress (SMARD1). Neuroscience 2018; 386:24-40. [DOI: 10.1016/j.neuroscience.2018.06.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 06/03/2018] [Accepted: 06/11/2018] [Indexed: 12/31/2022]
|
46
|
Park SR, Kim HJ, Yang SR, Park CH, Lee HY, Hong IS. A novel endogenous damage signal, glycyl tRNA synthetase, activates multiple beneficial functions of mesenchymal stem cells. Cell Death Differ 2018; 25:2023-2036. [PMID: 29666468 DOI: 10.1038/s41418-018-0099-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 02/06/2018] [Accepted: 03/06/2018] [Indexed: 01/06/2023] Open
Abstract
During tissue repair, the injury site releases various bioactive molecules as damage signals to actively recruit stem cells to the damaged region. Despite convincing evidence that mesenchymal stem cells (MSCs) can sense damage signals and promote repair processes, the identity of these signals and how these signals regulate stem cell-mediated tissue repair remain unknown. Glycyl tRNA synthetase (GRS) is a ubiquitously expressed enzyme that catalyzes the first step of protein synthesis in all organisms. In addition to this canonical function, we identified for the first time that GRS is released by damaged tissues or cells in response to various injury signals and may function as a damage signal that activates the proliferative, differentiation, and migratory potential of MSCs, possibly through its identified receptor, cadherin-6 (CDH-6). Binding between GRS and CDH-6 activates survival signals, such as those of the PI3K/Akt and/or FAK/ERK1/2 pathways. More importantly, we also found that MSCs stimulated with GRS show significantly improved homing and differentiation potential and subsequent in vivo therapeutic effects, in a liver fibrosis animal model. Collectively, our findings provide compelling evidence for a novel function of GRS in enhancing the multiple beneficial functions of stem cells via a non-canonical mechanism as a damage signal.
Collapse
Affiliation(s)
- Se-Ra Park
- Laboratory of Stem Cell Research, Lee Gil Ya Cancer and Diabetes Institute, Gachon University, Incheon, 406-840, Republic of Korea.,Department of Molecular Medicine, School of Medicine, Gachon University, Incheon, 406-840, Republic of Korea
| | - Hyun-Jin Kim
- Laboratory of Stem Cell Research, Lee Gil Ya Cancer and Diabetes Institute, Gachon University, Incheon, 406-840, Republic of Korea.,Department of Molecular Medicine, School of Medicine, Gachon University, Incheon, 406-840, Republic of Korea
| | - Se-Ran Yang
- Department of Thoracic and Cardiovascular Surgery, Kangwon National University, Chuncheon, South Korea
| | - Chan Hum Park
- Department of Otolaryngology-Head and Neck Surgery, Chuncheon Sacred Heart Hospital, Hallym University College of Medicine, Chuncheon, South Korea
| | - Hwa-Yong Lee
- Department of Biomedical Science, Jungwon University, 85 Goesan-eup, Munmu-ro, Goesan-gun, 367-700, Republic of Korea.
| | - In-Sun Hong
- Laboratory of Stem Cell Research, Lee Gil Ya Cancer and Diabetes Institute, Gachon University, Incheon, 406-840, Republic of Korea. .,Department of Molecular Medicine, School of Medicine, Gachon University, Incheon, 406-840, Republic of Korea.
| |
Collapse
|
47
|
Rips J, Meyer-Schuman R, Breuer O, Tsabari R, Shaag A, Revel-Vilk S, Reif S, Elpeleg O, Antonellis A, Harel T. MARS variant associated with both recessive interstitial lung and liver disease and dominant Charcot-Marie-Tooth disease. Eur J Med Genet 2018; 61:616-620. [PMID: 29655802 DOI: 10.1016/j.ejmg.2018.04.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 04/10/2018] [Accepted: 04/11/2018] [Indexed: 12/25/2022]
Abstract
Aminoacyl-tRNA synthetases (ARSs) are ubiquitously expressed enzymes responsible for charging tRNA with cognate amino acids during protein translation. Non-canonical functions are increasingly recognized, and include transcription and translation control and extracellular signaling. Monoallelic mutations in genes encoding several ARSs have been identified in axonal Charcot-Marie-Tooth (CMT2) disease, whereas biallelic mutations in ARS loci have been associated with multi-tissue syndromes, variably involving the central nervous system, lung, and liver. We report a male infant of non-consanguineous origin, presenting with successive onset of transfusion-dependent anemia, hypothyroidism, cholestasis, interstitial lung disease, and developmental delay. Whole-exome sequencing (WES) revealed compound heterozygosity for two variants (p.Tyr307Cys and p.Arg618Cys) in MARS, encoding methionyl-tRNA synthetase. Biallelic MARS mutations are associated with interstitial lung and liver disease (ILLD). Interestingly, the p.Arg618Cys variant, inherited from an unaffected father, was previously reported in a family with autosomal dominant late-onset CMT2. Yeast complementation assays confirmed pathogenicity of p.Arg618Cys, yet suggested retained function of p.Tyr307Cys. Our findings underscore the phenotypic variability associated with ARS mutations, and suggest genetic or environmental modifying factors in the onset of monoallelic MARS-associated CMT2.
Collapse
Affiliation(s)
- Jonathan Rips
- Department of Pediatrics, Hadassah Ein-Kerem Medical Center, Jerusalem, Israel
| | - Rebecca Meyer-Schuman
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI, United States
| | - Oded Breuer
- Pediatric Pulmonology Unit, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Reuven Tsabari
- Pediatric Pulmonology Unit, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Avraham Shaag
- Department of Genetic and Metabolic Diseases, Hadassah-Hebrew University Medical Center, Jerusalem, Israel; Monique and Jacques Roboh Department of Genetic Research, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Shoshana Revel-Vilk
- Pediatric Hematology, Shaare Zedek Medical Center, Hebrew University, Jerusalem, Israel
| | - Shimon Reif
- Department of Pediatrics, Hadassah Ein-Kerem Medical Center, Jerusalem, Israel
| | - Orly Elpeleg
- Department of Genetic and Metabolic Diseases, Hadassah-Hebrew University Medical Center, Jerusalem, Israel; Monique and Jacques Roboh Department of Genetic Research, Hadassah-Hebrew University Medical Center, Jerusalem, Israel.
| | - Anthony Antonellis
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI, United States; Department of Neurology, University of Michigan Medical School, Ann Arbor, MI, United States
| | - Tamar Harel
- Department of Genetic and Metabolic Diseases, Hadassah-Hebrew University Medical Center, Jerusalem, Israel.
| |
Collapse
|
48
|
Mo Z, Zhao X, Liu H, Hu Q, Chen XQ, Pham J, Wei N, Liu Z, Zhou J, Burgess RW, Pfaff SL, Caskey CT, Wu C, Bai G, Yang XL. Aberrant GlyRS-HDAC6 interaction linked to axonal transport deficits in Charcot-Marie-Tooth neuropathy. Nat Commun 2018. [PMID: 29520015 PMCID: PMC5843656 DOI: 10.1038/s41467-018-03461-z] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Dominant mutations in glycyl-tRNA synthetase (GlyRS) cause a subtype of Charcot-Marie-Tooth neuropathy (CMT2D). Although previous studies have shown that GlyRS mutants aberrantly interact with Nrp1, giving insight into the disease’s specific effects on motor neurons, these cannot explain length-dependent axonal degeneration. Here, we report that GlyRS mutants interact aberrantly with HDAC6 and stimulate its deacetylase activity on α-tubulin. A decrease in α-tubulin acetylation and deficits in axonal transport are observed in mice peripheral nerves prior to disease onset. An HDAC6 inhibitor used to restore α-tubulin acetylation rescues axonal transport deficits and improves motor functions of CMT2D mice. These results link the aberrant GlyRS-HDAC6 interaction to CMT2D pathology and suggest HDAC6 as an effective therapeutic target. Moreover, the HDAC6 interaction differs from Nrp1 interaction among GlyRS mutants and correlates with divergent clinical presentations, indicating the existence of multiple and different mechanisms in CMT2D. Mutations in glycyl-tRNA synthetase (GlyRS) cause Charcot-Marie-Tooth disease, a neuromuscular disorder characterized by axonal degeneration. Here the authors show that mutant GlyRS interacts with histone deacetylase 6, resulting in increased deacetylation of α-tubulin and axonal transport deficits.
Collapse
Affiliation(s)
- Zhongying Mo
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Xiaobei Zhao
- Department of Neurosciences, University of California at San Diego, La Jolla, CA, 92093, USA
| | - Huaqing Liu
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Qinghua Hu
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Xu-Qiao Chen
- Department of Neurosciences, University of California at San Diego, La Jolla, CA, 92093, USA
| | - Jessica Pham
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Na Wei
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Ze Liu
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Jiadong Zhou
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | | | - Samuel L Pfaff
- Howard Hughes Medical Institute and Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, CA, 92037, USA
| | | | - Chengbiao Wu
- Department of Neurosciences, University of California at San Diego, La Jolla, CA, 92093, USA.,Veterans Affairs San Diego Healthcare System, San Diego, 92161, CA, USA
| | - Ge Bai
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, 92037, USA.,Howard Hughes Medical Institute and Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, CA, 92037, USA
| | - Xiang-Lei Yang
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, 92037, USA.
| |
Collapse
|
49
|
Grice SJ, Sleigh JN, Zameel Cader M. Plexin-Semaphorin Signaling Modifies Neuromuscular Defects in a Drosophila Model of Peripheral Neuropathy. Front Mol Neurosci 2018. [PMID: 29520219 PMCID: PMC5827687 DOI: 10.3389/fnmol.2018.00055] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Dominant mutations in GARS, encoding the ubiquitous enzyme glycyl-tRNA synthetase (GlyRS), cause peripheral nerve degeneration and Charcot-Marie-Tooth disease type 2D (CMT2D). This genetic disorder exemplifies a recurring paradigm in neurodegeneration, in which mutations in essential genes cause selective degeneration of the nervous system. Recent evidence suggests that the mechanism underlying CMT2D involves extracellular neomorphic binding of mutant GlyRS to neuronally-expressed proteins. Consistent with this, our previous studies indicate a non-cell autonomous mechanism, whereby mutant GlyRS is secreted and interacts with the neuromuscular junction (NMJ). In this Drosophila model for CMT2D, we have previously shown that mutant gars expression decreases viability and larval motor function, and causes a concurrent build-up of mutant GlyRS at the larval neuromuscular presynapse. Here, we report additional phenotypes that closely mimic the axonal branching defects of Drosophila plexin transmembrane receptor mutants, implying interference of plexin signaling in gars mutants. Individual dosage reduction of two Drosophila Plexins, plexin A (plexA) and B (plexB) enhances and represses the viability and larval motor defects caused by mutant GlyRS, respectively. However, we find plexB levels, but not plexA levels, modify mutant GlyRS association with the presynaptic membrane. Furthermore, increasing availability of the plexB ligand, Semaphorin-2a (Sema2a), alleviates the pathology and the build-up of mutant GlyRS, suggesting competition for plexB binding may be occurring between these two ligands. This toxic gain-of-function and subversion of neurodevelopmental processes indicate that signaling pathways governing axonal guidance could be integral to neuropathology and may underlie the non-cell autonomous CMT2D mechanism.
Collapse
Affiliation(s)
- Stuart J Grice
- MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - James N Sleigh
- Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London, London, United Kingdom
| | - M Zameel Cader
- MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom.,MRC Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
| |
Collapse
|
50
|
Boczonadi V, Jennings MJ, Horvath R. The role of tRNA synthetases in neurological and neuromuscular disorders. FEBS Lett 2018; 592:703-717. [PMID: 29288497 PMCID: PMC5873386 DOI: 10.1002/1873-3468.12962] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 12/06/2017] [Accepted: 12/21/2017] [Indexed: 12/11/2022]
Abstract
Aminoacyl‐tRNA synthetases (ARSs) are ubiquitously expressed enzymes responsible for charging tRNAs with their cognate amino acids, therefore essential for the first step in protein synthesis. Although the majority of protein synthesis happens in the cytosol, an additional translation apparatus is required to translate the 13 mitochondrial DNA‐encoded proteins important for oxidative phosphorylation. Most ARS genes in these cellular compartments are distinct, but two genes are common, encoding aminoacyl‐tRNA synthetases of glycine (GARS) and lysine (KARS) in both mitochondria and the cytosol. Mutations in the majority of the 37 nuclear‐encoded human ARS genes have been linked to a variety of recessive and dominant tissue‐specific disorders. Current data indicate that impaired enzyme function could explain the pathogenicity, however not all pathogenic ARSs mutations result in deficient catalytic function; thus, the consequences of mutations may arise from other molecular mechanisms. The peripheral nerves are frequently affected, as illustrated by the high number of mutations in cytosolic and bifunctional tRNA synthetases causing Charcot–Marie–Tooth disease (CMT). Here we provide insights on the pathomechanisms of CMT‐causing tRNA synthetases with specific focus on the two bifunctional tRNA synthetases (GARS, KARS).
Collapse
Affiliation(s)
- Veronika Boczonadi
- Wellcome Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - Matthew J Jennings
- Wellcome Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - Rita Horvath
- Wellcome Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
| |
Collapse
|