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Abstract
Significance: Routine exposure to xenobiotics is unavoidable during our lifetimes. Certain xenobiotics are hazardous to human health, and are metabolized in the body to render them less toxic. During this process, several detoxification enzymes cooperatively metabolize xenobiotics. Glutathione (GSH) conjugation plays an important role in the metabolism of electrophilic xenobiotics. Recent Advances: Recent advances in reactive sulfur and supersulfide (RSS) analyses showed that persulfides and polysulfides bound to low-molecular-weight thiols, such as GSH, and to protein thiols are abundant in both eukaryotes and prokaryotes. The highly nucleophilic nature of hydropersulfides and hydropolysulfides contributes to cell protection against oxidative stress and electrophilic stress. Critical Issues: In contrast to GSH conjugation to electrophiles that is aided by glutathione S-transferase (GST), persulfides and polysulfides can directly form conjugates with electrophiles without the catalytic actions of GST. The polysulfur bonds in the conjugates are further reduced by perthioanions and polythioanions derived from RSS to form sulfhydrated metabolites that are no longer electrophilic but rather nucleophilic, and differ from metabolites that are formed via GSH conjugation. Future Directions: In view of the abundance of RSS in cells and tissues, metabolism of xenobiotics that is mediated by RSS warrants additional investigations, such as studies of the impact of microbiota-derived RSS on xenobiotic metabolism. Metabolites formed from reactions between electrophiles and RSS may be potential biomarkers for monitoring exposure to electrophiles and for studying their metabolism by RSS. Antioxid. Redox Signal. 40, 679-690.
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Affiliation(s)
- Tianli Zhang
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Takaaki Akaike
- Department of Environmental Medicine and Molecular Toxicology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Tomohiro Sawa
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
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Tsutsuki H, Zhang T, Akaike T, Sawa T. Regulation of innate immune and inflammatory responses by supersulfides. Int Immunol 2024; 36:143-154. [PMID: 38180817 DOI: 10.1093/intimm/dxad057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2023] [Accepted: 01/04/2024] [Indexed: 01/07/2024] Open
Abstract
Innate immunity plays an important role in host defense against microbial infections. It also participates in activation of acquired immunity through cytokine production and antigen presentation. Pattern recognition receptors such as Toll-like receptors and nucleotide oligomerization domain-like receptors sense invading pathogens and associated tissue injury, after which inflammatory mediators such as pro-inflammatory cytokines and nitric oxide are induced. Supersulfides are molecular species possessing catenated sulfur atoms such as persulfide and polysulfide moieties. They have recently been recognized as important regulators in cellular redox homeostasis by acting as potent antioxidants and nucleophiles. In addition, recent studies suggested that supersulfides are critically involved in the regulation of innate immune and inflammatory responses. In this review, we summarize current knowledge of the chemistry and biology of supersulfides, with particular attention to their roles in regulation of innate immune, and inflammatory responses. Studies with animal models of infection and inflammation demonstrated the potent anti-inflammatory functions of supersulfides such as blocking pro-inflammatory signaling cascades, reducing oxidative stresses, and inhibiting replication of microbial pathogens including severe acute respiratory syndrome coronavirus 2. Precise understanding of how supersulfides regulate innate immune responses is the necessary requirement for developing supersulfide-based diagnostic as well as therapeutic strategies against inflammatory disorders.
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Affiliation(s)
- Hiroyasu Tsutsuki
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Tianli Zhang
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Takaaki Akaike
- Department of Environmental Medicine and Molecular Toxicology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8574, Japan
| | - Tomohiro Sawa
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan
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Huang SS, Wu LY, Qiu Y, Xie Y, Wu H, Li YQ, Xie XH. Identification of lactate-related subgroups and prognostic model in triple-negative breast cancer. J Cancer Res Clin Oncol 2023; 149:13107-13122. [PMID: 37474680 DOI: 10.1007/s00432-023-05171-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 07/09/2023] [Indexed: 07/22/2023]
Abstract
BACKGROUND Triple-negative breast cancer (TNBC) is a highly aggressive subtype of breast cancer that exhibits elevated glycolytic capacity. Lactate, as a byproduct of glycolysis, is considered a major oncometabolite that plays an important role in oncogenesis and remodeling of the tumor microenvironment. However, the potential roles of lactate in TNBC are not yet fully understood. In this study, our goal was to identify prognosis-related lactate genes (PLGs) and construct a lactate-related prognostic model (LRPM) for TNBC. METHODS First, we applied lactate-related genes to classify TNBC samples using a hierarchical clustering algorithm. Then, we performed the log-rank analysis and the least absolute shrinkage and selection operator analysis to screen PLGs and construct the LRPM. The biological functions of the identified PLGs in TNBC were investigated using CCK8 assay and clone formation assay. Finally, we constructed a nomogram based on the lactate-risk score and tumor clinical stage. We used the operating characteristic curve and decision curve analysis to evaluate the predictive capability of the nomogram. RESULTS Our results showed that the TNBC samples could be classified into two subgroups with different survival probabilities. Three genes (NDUFAF3, CARS2 and FH), which can suppress TNBC cell proliferation, were identified as PLGs. Moreover, the LRPM and nomogram exhibited excellent predictive performance for TNBC patient prognosis. CONCLUSION We have developed a novel LRPM that enables risk stratification and identification of poor molecular subtypes in TNBC patients, showing great potential in clinical practice.
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Affiliation(s)
- Shan-Shan Huang
- Department of Breast Oncology, State Key Laboratory of Oncology in South China, Sun Yat-Sen University Cancer Center, 651 Dongfeng Road East, Guangzhou, 510060, China
| | - Lin-Yu Wu
- Department of Breast Oncology, State Key Laboratory of Oncology in South China, Sun Yat-Sen University Cancer Center, 651 Dongfeng Road East, Guangzhou, 510060, China
| | - Yu Qiu
- Department of Breast Oncology, State Key Laboratory of Oncology in South China, Sun Yat-Sen University Cancer Center, 651 Dongfeng Road East, Guangzhou, 510060, China
| | - Yi Xie
- Department of Breast Oncology, State Key Laboratory of Oncology in South China, Sun Yat-Sen University Cancer Center, 651 Dongfeng Road East, Guangzhou, 510060, China
| | - Hao Wu
- Department of Breast Oncology, State Key Laboratory of Oncology in South China, Sun Yat-Sen University Cancer Center, 651 Dongfeng Road East, Guangzhou, 510060, China
| | - Ying-Qing Li
- Outpatient Department, State Key Laboratory of Oncology in South China, Sun Yat-Sen University Cancer Center, 651 Dongfeng Road East, Guangzhou, 510060, China.
| | - Xin-Hua Xie
- Department of Breast Oncology, State Key Laboratory of Oncology in South China, Sun Yat-Sen University Cancer Center, 651 Dongfeng Road East, Guangzhou, 510060, China.
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Ogata S, Matsunaga T, Jung M, Barayeu U, Morita M, Akaike T. Persulfide Biosynthesis Conserved Evolutionarily in All Organisms. Antioxid Redox Signal 2023; 39:983-999. [PMID: 37565274 PMCID: PMC10655014 DOI: 10.1089/ars.2023.0405] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 08/04/2023] [Indexed: 08/12/2023]
Abstract
Significance: Persulfides/polysulfides are sulfur-catenated molecular species (i.e., R-Sn-R', n > 2; R-Sn-H, n > 1, with R = cysteine, glutathione, and proteins), such as cysteine persulfide (CysSSH). These species are abundantly formed as endogenous metabolites in mammalian and human cells and tissues. However, the persulfide synthesis mechanism has yet to be thoroughly discussed. Recent Advances: We used β-(4-hydroxyphenyl)ethyl iodoacetamide and mass spectrometry to develop sulfur metabolomics, a highly precise, quantitative analytical method for sulfur metabolites. Critical Issues: With this method, we detected appreciable amounts of different persulfide species in biological specimens from various organisms, from the domains Bacteria, Archaea, and Eukarya. By using our rigorously quantitative approach, we identified cysteinyl-tRNA synthetase (CARS) as a novel persulfide synthase, and we found that the CysSSH synthase activity of CARS is highly conserved from the domains Bacteria to Eukarya. Because persulfide synthesis is found not only with CARS but also with other sulfotransferase enzymes in many organisms, persulfides/polysulfides are expected to contribute as fundamental elements to substantially diverse biological phenomena. In fact, persulfide generation in higher organisms-that is, plants and animals-demonstrated various physiological functions that are mediated by redox signaling, such as regulation of energy metabolism, infection, inflammation, and cell death, including ferroptosis. Future Directions: Investigating CARS-dependent persulfide production may clarify various pathways of redox signaling in physiological and pathophysiological conditions and may thereby promote the development of preventive and therapeutic measures for oxidative stress as well as different inflammatory, metabolic, and neurodegenerative diseases. Antioxid. Redox Signal. 39, 983-999.
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Affiliation(s)
- Seiryo Ogata
- Department of Environmental Medicine and Molecular Toxicology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Tetsuro Matsunaga
- Department of Environmental Medicine and Molecular Toxicology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Minkyung Jung
- Department of Environmental Medicine and Molecular Toxicology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Uladzimir Barayeu
- Department of Environmental Medicine and Molecular Toxicology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Masanobu Morita
- Department of Environmental Medicine and Molecular Toxicology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Takaaki Akaike
- Department of Environmental Medicine and Molecular Toxicology, Tohoku University Graduate School of Medicine, Sendai, Japan
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Kong LY, Wu YZ, Cheng RQ, Wang PH, Peng BW. Role of Mutations of Mitochondrial Aminoacyl-tRNA Synthetases Genes on Epileptogenesis. Mol Neurobiol 2023; 60:5482-5492. [PMID: 37316759 DOI: 10.1007/s12035-023-03429-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 06/05/2023] [Indexed: 06/16/2023]
Abstract
Mitochondria are the structures in cells that are responsible for producing energy. They contain a specific translation unit for synthesizing mitochondria-encoded respiratory chain components: the mitochondrial DNA (mt DNA). Recently, a growing number of syndromes associated with the dysfunction of mt DNA translation have been reported. However, the functions of these diseases still need to be precise and thus attract much attention. Mitochondrial tRNAs (mt tRNAs) are encoded by mt DNA; they are the primary cause of mitochondrial dysfunction and are associated with a wide range of pathologies. Previous research has shown the role of mt tRNAs in the epileptic mechanism. This review will focus on the function of mt tRNA and the role of mitochondrial aminoacyl-tRNA synthetase (mt aaRS) in order to summarize some common relevant mutant genes of mt aaRS that cause epilepsy and the specific symptoms of the disease they cause.
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Affiliation(s)
- Ling-Yue Kong
- Department of Physiology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Yi-Ze Wu
- Department of Physiology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Run-Qi Cheng
- Department of Physiology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Pei-Han Wang
- Department of Physiology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Bi-Wen Peng
- Department of Physiology, School of Basic Medical Sciences, Wuhan University, Wuhan, China.
- Department of Physiology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, School of Basic Medical Sciences, Wuhan University, Donghu Rd185#, Wuhan, 430071, Hubei, China.
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Abdulkareem AA, Zaman Q, Khan H, Khan S, Rehman G, Tariq N, Ahmad M, Owais M, Najumuddin, Muthaffar OY, Bibi F, Khang R, Ryu SW, Naseer MI, Jelani M. Whole exome sequencing identified five novel variants in CNTN2, CARS2, ARSA, and CLCN4 leading to epilepsy in consanguineous families. Front Genet 2023; 14:1185065. [PMID: 37359369 PMCID: PMC10285458 DOI: 10.3389/fgene.2023.1185065] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 05/26/2023] [Indexed: 11/20/2023] Open
Abstract
Introduction: Epilepsy is a group of neurological disorders characterized by recurring seizures and fits. The Epilepsy genes can be classified into four distinct groups, based on involvement of these genes in different pathways leading to Epilepsy as a phenotype. Genetically the disease has been associated with various pathways, leading to pure epilepsy-related disorders caused by CNTN2 variations, or involving physical or systemic issues along with epilepsy caused by CARS2 and ARSA, or developed by genes that are putatively involved in epilepsy lead by CLCN4 variations. Methods: In this study, five families of Pakistani origin (EP-01, EP-02, EP-04, EP-09, and EP-11) were included for molecular diagnosis. Results: Clinical presentations of these patients included neurological symptoms such as delayed development, seizures, regression, myoclonic epilepsy, progressive spastic tetraparesis, vision and hearing impairment, speech problems, muscle fibrillation, tremors, and cognitive decline. Whole exome sequencing in index patients and Sanger sequencing in all available individuals in each family identified four novel homozygous variants in genes CARS2: c.655G>A p.Ala219Thr (EP-01), ARSA: c.338T>C: p.Leu113Pro (EP-02), c.938G>T p.Arg313Leu (EP-11), CNTN2: c.1699G>T p.Glu567Ter (EP-04), and one novel hemizygous variant in gene CLCN4: c.2167C>T p.Arg723Trp (EP-09). Conclusion: To the best of our knowledge these variants were novel and had not been reported in familial epilepsy. These variants were absent in 200 ethnically matched healthy control chromosomes. Three dimensional protein analyses revealed drastic changes in the normal functions of the variant proteins. Furthermore, these variants were designated as "pathogenic" as per guidelines of American College of Medical Genetics 2015. Due to overlapping phenotypes, among the patients, clinical subtyping was not possible. However, whole exome sequencing successfully pinpointed the molecular diagnosis which could be helpful for better management of these patients. Therefore, we recommend that exome sequencing be performed as a first-line molecular diagnostic test in familial cases.
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Affiliation(s)
- Angham Abdulrhman Abdulkareem
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia
- Center of Excellence in Genomic Medicine Research, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Qaiser Zaman
- Department of Zoology, Government Postgraduate College Dargai, Malakand, Khyber Pakhtunkhwa, Pakistan
- Higher Education Department, Peshawar, Khyber Pakhtunkhwa, Pakistan
- Department of Zoology, Abdul Wali Khan University, Mardan, Khyber Pakhtunkhwa, Pakistan
| | - Hamza Khan
- Department of Zoology, Government Postgraduate College Dargai, Malakand, Khyber Pakhtunkhwa, Pakistan
| | - Sabar Khan
- Department of Zoology, Government Postgraduate College Dargai, Malakand, Khyber Pakhtunkhwa, Pakistan
| | - Gauhar Rehman
- Department of Zoology, Abdul Wali Khan University, Mardan, Khyber Pakhtunkhwa, Pakistan
| | - Nabeel Tariq
- Department of Zoology, Government Postgraduate College Dargai, Malakand, Khyber Pakhtunkhwa, Pakistan
| | - Mashal Ahmad
- Department of Zoology, Government Postgraduate College Dargai, Malakand, Khyber Pakhtunkhwa, Pakistan
| | - Muhammad Owais
- Mardan College of Medical Technologies, Mardan, Khyber Pakhtunkhwa, Pakistan
| | - Najumuddin
- Programme of Biotechnology, Department of Applied Sciences, Faculty of Engineering, Science and Technology (FEST), Hamdard University, Karachi, Pakistan
| | - Osama Yousef Muthaffar
- Department of Pediatrics, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Fehmida Bibi
- Special Infectious Agents Unit, King Fahd Medical Research Centre, King Abdulaziz University, Jeddah, Saudi Arabia
- Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Rin Khang
- 3Billion Inc., Seoul, Republic of Korea
| | | | - Muhammad Imran Naseer
- Center of Excellence in Genomic Medicine Research, King Abdulaziz University, Jeddah, Saudi Arabia
- Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Musharraf Jelani
- Rare Diseases Genetics and Genomics, Centre for Omic Sciences, Islamia College, Peshawar, Khyber Pakhtunkhwa, Pakistan
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Poquérusse J, Nolan M, Thorburn DR, Van Hove JLK, Friederich MW, Love DR, Taylor J, Powell CA, Minczuk M, Snell RG, Lehnert K, Glamuzina E, Jacobsen JC. Severe neonatal onset neuroregression with paroxysmal dystonia and apnoea: Expanding the phenotypic and genotypic spectrum of CARS2-related mitochondrial disease. JIMD Rep 2023; 64:223-232. [PMID: 37151360 PMCID: PMC10159863 DOI: 10.1002/jmd2.12360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 01/08/2023] [Accepted: 01/10/2023] [Indexed: 01/24/2023] Open
Abstract
Disorders of mitochondrial function are a collectively common group of genetic diseases in which deficits in core mitochondrial translation machinery, including aminoacyl tRNA synthetases, are key players. Biallelic variants in the CARS2 gene (NM_024537.4), which encodes the mitochondrial aminoacyl-tRNA synthetase for cysteine (CARS2, mt-aaRScys; MIM*612800), result in childhood onset epileptic encephalopathy and complex movement disorder with combined oxidative phosphorylation deficiency (MIM#616672). Prior to this report, eight unique pathogenic variants in the CARS2 gene had been reported in seven individuals. Here, we describe a male who presented in the third week of life with apnoea. He rapidly deteriorated with paroxysmal dystonic crises and apnoea resulting in death at 16 weeks. He had no evidence of seizure activity or multisystem disease and had normal brain imaging. Skeletal muscle biopsy revealed a combined disorder of oxidative phosphorylation. Whole-exome sequencing identified biallelic variants in the CARS2 gene: one novel (c.1478T>C, p.Phe493Ser), and one previously reported (c.655G>A, p.Ala219Thr; rs727505361). Northern blot analysis of RNA isolated from the patient's fibroblasts confirmed a clear defect in aminoacylation of the mitochondrial tRNA for cysteine (mt-tRNACys). To our knowledge, this is the earliest reported case of CARS2 deficiency with severe, early onset dystonia and apnoea, without epilepsy.
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Affiliation(s)
- Jessie Poquérusse
- School of Biological SciencesThe University of AucklandAucklandNew Zealand
- Centre for Brain ResearchThe University of AucklandAucklandNew Zealand
| | - Melinda Nolan
- Department of NeurologyStarship Children's HealthAucklandNew Zealand
| | - David R. Thorburn
- Murdoch Children's Research InstituteMelbourneVictoriaAustralia
- Department of PaediatricsThe University of MelbourneMelbourneVictoriaAustralia
| | - Johan L. K. Van Hove
- Department of Pediatrics, School of MedicineUniversity of Colorado Anschutz Medical CampusAuroraColoradoUSA
- Department of Pathology and Laboratory MedicineChildren's Hospital ColoradoAuroraColoradoUSA
| | - Marisa W. Friederich
- Department of Pediatrics, School of MedicineUniversity of Colorado Anschutz Medical CampusAuroraColoradoUSA
- Department of Pathology and Laboratory MedicineChildren's Hospital ColoradoAuroraColoradoUSA
| | - Donald R. Love
- Diagnostic GeneticsLabPLUS, Auckland City HospitalAucklandNew Zealand
- Present address:
Division Chief, Pathology GeneticsSidra MedicineDohaQatar
| | - Juliet Taylor
- Genetic Health Service New ZealandAuckland City HospitalAucklandNew Zealand
| | | | - Michal Minczuk
- MRC Mitochondrial Biology UnitUniversity of CambridgeCambridgeUK
| | - Russell G. Snell
- School of Biological SciencesThe University of AucklandAucklandNew Zealand
- Centre for Brain ResearchThe University of AucklandAucklandNew Zealand
| | - Klaus Lehnert
- School of Biological SciencesThe University of AucklandAucklandNew Zealand
- Centre for Brain ResearchThe University of AucklandAucklandNew Zealand
| | - Emma Glamuzina
- Adult and Paediatric National Metabolic ServiceAuckland City HospitalAucklandNew Zealand
| | - Jessie C. Jacobsen
- School of Biological SciencesThe University of AucklandAucklandNew Zealand
- Centre for Brain ResearchThe University of AucklandAucklandNew Zealand
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Chen S, Neale BM, Berkovic SF. Shared and distinct ultra-rare genetic risk for diverse epilepsies: A whole-exome sequencing study of 54,423 individuals across multiple genetic ancestries. medRxiv 2023:2023.02.22.23286310. [PMID: 36865150 PMCID: PMC9980234 DOI: 10.1101/2023.02.22.23286310] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
Abstract
Identifying genetic risk factors for highly heterogeneous disorders like epilepsy remains challenging. Here, we present the largest whole-exome sequencing study of epilepsy to date to investigate rare variants that confer risk for a spectrum of epilepsy syndromes. With an unprecedented sample size of >54,000 human exomes, composed of 20,979 deep-phenotyped patients with epilepsy and 33,444 controls, we replicate previous gene findings at exome-wide significance; using a hypothesis-free approach, we identify potential novel associations. Most discoveries are specific to a particular subtype of epilepsy, highlighting distinct genetic contributions to different epilepsies. Combining evidence from rare single nucleotide/short indel-, copy number-, and common variants, we find convergence of different genetic risk factors at the level of individual genes. Further comparing to other exome-sequencing studies, we implicate shared rare variant risk between epilepsy and other neurodevelopmental disorders. Our study also demonstrates the value of collaborative sequencing and deep-phenotyping efforts, which will continue to unravel the complex genetic architecture underlying the heterogeneity of epilepsy.
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Affiliation(s)
- Siwei Chen
- Analytic and Translational Genetics Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Benjamin M Neale
- Analytic and Translational Genetics Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Samuel F Berkovic
- Epilepsy Research Centre, University of Melbourne, Austin Health, Heidelberg 3084, Australia
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Abstract
The human brain consumes five orders of magnitude more energy than the sun by unit of mass and time. This staggering bioenergetic cost serves mostly synaptic transmission and actin cytoskeleton dynamics. The peak of both brain bioenergetic demands and the age of onset for neurodevelopmental disorders is approximately 5 years of age. This correlation suggests that defects in the machinery that provides cellular energy would be causative and/or consequence of neurodevelopmental disorders. We explore this hypothesis from the perspective of the machinery required for the synthesis of the electron transport chain, an ATP-producing and NADH-consuming enzymatic cascade. The electron transport chain is constituted by nuclear- and mitochondrial-genome-encoded subunits. These subunits are synthesized by the 80S and the 55S ribosomes, which are segregated to the cytoplasm and the mitochondrial matrix, correspondingly. Mitochondrial protein synthesis by the 55S ribosome is the rate-limiting step in the synthesis of electron transport chain components, suggesting that mitochondrial protein synthesis is a bottleneck for tissues with high bionergetic demands. We discuss genetic defects in the human nuclear and mitochondrial genomes that affect these protein synthesis machineries and cause a phenotypic spectrum spanning autism spectrum disorders to neurodegeneration during neurodevelopment. We propose that dysregulated mitochondrial protein synthesis is a chief, yet understudied, causative mechanism of neurodevelopmental and behavioral disorders.
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10
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Dang A, Turner AW, Lau P, Mohottalage D, Stephanie Fong YK, Eriksson P, Folkersen L, Matic L, Hedin U, Soubeyrand S, Mcpherson R. A novel anti-inflammatory role links the CARS2 locus to protection from coronary artery disease. Atherosclerosis 2022. [DOI: 10.1016/j.atherosclerosis.2022.03.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 03/16/2022] [Accepted: 03/25/2022] [Indexed: 11/18/2022]
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Chan DL, Rudinger-Thirion J, Frugier M, Riley LG, Ho G, Kothur K, Mohammad SS. A case of QARS1 associated epileptic encephalopathy and review of epilepsy in aminoacyl-tRNA synthetase disorders. Brain Dev 2022; 44:142-147. [PMID: 34774383 DOI: 10.1016/j.braindev.2021.10.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 09/21/2021] [Accepted: 10/22/2021] [Indexed: 12/30/2022]
Abstract
INTRODUCTION Mutations in QARS1, which encodes human glutaminyl-tRNA synthetase, have been associated with epilepsy, developmental regression, progressive microcephaly and cerebral atrophy. Epilepsy caused by variants in QARS1 is usually drug-resistant and intractable. Childhood onset epilepsy is also reported in various aminoacyl-tRNA synthetase disorders. We describe a case with a milder neurological phenotype than previously reported with QARS1 variants and review the seizure associations with aminoacyl-tRNA synthetase disorders. CASE REPORT The patient is a 4-year-old girl presenting at 6 weeks of age with orofacial dyskinesia and hand stereotypies. She developed focal seizures at 7 months of age. Serial electroencephalograms showed shifting focality. Her seizures were controlled after introduction of carbamazepine. Progress MRI showed very mild cortical volume loss without myelination abnormalities or cerebellar atrophy. She was found to have novel compound heterozygous variants in QARS1 (NM_005051.2): c.[1132C > T];[1574G > A], p.[(Arg378Cys)];[(Arg525Gln)] originally classified as "variants of uncertain significance" and later upgraded to "likely pathogenic" based on functional testing and updated variant database review. Functional testing showed reduced solubility of the corresponding QARS1 mutants in vitro, but only mild two-fold loss in catalytic efficiency with the c.1132C > T variant and no noted change in tRNAGln aminoacylation with the c.1574G > A variant. CONCLUSION We describe two QARS1 variants associated with overall conserved tRNA aminoacylation activity but characterized by significantly reduced QARS protein solubility, resulting in a milder clinical phenotype. 86% of previous patients reported with QARS1 had epilepsy and 79% were pharmaco-resistant. We also summarise literature regarding epilepsy in aminoacyl-tRNA synthetase disorders, which is also often early onset, severe and drug-refractory.
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Affiliation(s)
- Denise L Chan
- Neurology Department, Sydney Children's Hospital, Sydney, Australia, School of Women's and Children's Health, UNSW Medicine, UNSW Sydney, Australia
| | - Joëlle Rudinger-Thirion
- Université de Strasbourg, CNRS,Architecture et Réactivité de l'ARN, UPR 9002, F-67000, Strasbourg, France
| | - Magali Frugier
- Université de Strasbourg, CNRS,Architecture et Réactivité de l'ARN, UPR 9002, F-67000, Strasbourg, France
| | - Lisa G Riley
- Rare Diseases Functional Genomics, Kids Research, Sydney Children's Hospital Network & Children's Medical Research Institute, Sydney Children's Hospital Network, Sydney, NSW 2145, Australia, Discipline of Child & Adolescent Health, Sydney Medical School, University of Sydney, Sydney, NSW 2006, Australia
| | - Gladys Ho
- Sydney Genome Diagnostics, Western Sydney Genetics Program, The Children's Hospital at Westmead, Sydney, Australia, Discipline of Child & Adolescent Health, Discipline of Genetic Medicine, The University of Sydney, Sydney, Australia; Children's Hospital at Westmead Clinical School, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
| | - Kavitha Kothur
- Children's Hospital at Westmead Clinical School, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
| | - Shekeeb S Mohammad
- Children's Hospital at Westmead Clinical School, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia; TY Nelson Department of Neurology and Neurosurgery, The Children's Hospital at Westmead, Sydney, NSW, Australia, Kids Neuroscience Centre, Kids Research, The Children's Hospital at Westmead, The University of Sydney, Sydney, NSW, Australia.
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12
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Sawa T, Takata T, Matsunaga T, Ihara H, Motohashi H, Akaike T. Chemical Biology of Reactive Sulfur Species: Hydrolysis-Driven Equilibrium of Polysulfides as a Determinant of Physiological Functions. Antioxid Redox Signal 2022; 36:327-336. [PMID: 34409860 PMCID: PMC8865625 DOI: 10.1089/ars.2021.0170] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Significance: Polysulfide species (i.e., R-Sn-R', n > 2; and R-Sn-H, n > 1) exist in many organisms. The highly nucleophilic nature of hydropersulfides and hydropolysulfides contributes to the potent antioxidant activities of polysulfide species that protect organisms against oxidative and electrophilic stresses. Recent Advances: Accumulating evidence suggests that organic polysulfides (R-Sn-R') readily undergo alkaline hydrolysis, which results in formation of both nucleophilic hydrosulfide/polysulfide (R-Sn-1H) and electrophilic sulfenic acid (R'SOH) species. Polysulfides maintain a steady-state equilibrium that is driven by hydrolysis even in aqueous physiological milieus. This unique property makes polysulfide chemistry and biology more complex than previously believed. Critical Issues: The hydrolysis equilibrium of polysulfides shifts to the right when electrophiles are present. Strong electrophilic alkylating agents (e.g., monobromobimane) greatly enhance polysulfide hydrolysis, which leads to increased polysulfide degradation and artifactual formation of bis-S-bimane adducts in the absence of free hydrogen sulfide. The finding that hydroxyl group-containing substances such as tyrosine efficiently protected polysulfides from hydrolysis led to development of the new alkylating agent, N-iodoacetyl l-tyrosine methyl ester (TME-IAM). TME-IAM efficiently and specifically traps and stabilizes hydropolysulfides and protects polysulfide chains from hydrolysis, and, when used with mass spectrometry, TME-IAM allows speciation of the reactive sulfur metabolome. In addition, the polyethylene glycol-conjugated maleimide-labeling gel shift assay, which relies on unique hydrolysis equilibrium of polysulfides, will be a reliable technique for proteomics of polysulfide-containing proteins. Future Directions: Using precise methodologies to achieve a better understanding of the occurrence and metabolism of polysulfide species is necessary to gain insights into the undefined biology of polysulfide species. Antioxid. Redox Signal. 36, 327-336.
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Affiliation(s)
- Tomohiro Sawa
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Tsuyoshi Takata
- Department of Environmental Medicine and Molecular Toxicology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Tetsuro Matsunaga
- Department of Environmental Medicine and Molecular Toxicology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Hideshi Ihara
- Department of Biological Sciences, Graduate School of Science, Osaka Prefecture University, Osaka, Japan
| | - Hozumi Motohashi
- Department of Gene Expression Regulation, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan
| | - Takaaki Akaike
- Department of Environmental Medicine and Molecular Toxicology, Tohoku University Graduate School of Medicine, Sendai, Japan
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13
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Fan W, Jin X, Xu M, Xi Y, Lu W, Yang X, Guan MX, Ge W. FARS2 deficiency in Drosophila reveals the developmental delay and seizure manifested by aberrant mitochondrial tRNA metabolism. Nucleic Acids Res 2021; 49:13108-13121. [PMID: 34878141 PMCID: PMC8682739 DOI: 10.1093/nar/gkab1187] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 11/08/2021] [Accepted: 11/17/2021] [Indexed: 01/16/2023] Open
Abstract
Mutations in genes encoding mitochondrial aminoacyl-tRNA synthetases are linked to diverse diseases. However, the precise mechanisms by which these mutations affect mitochondrial function and disease development are not fully understood. Here, we develop a Drosophila model to study the function of dFARS2, the Drosophila homologue of the mitochondrial phenylalanyl–tRNA synthetase, and further characterize human disease-associated FARS2 variants. Inactivation of dFARS2 in Drosophila leads to developmental delay and seizure. Biochemical studies reveal that dFARS2 is required for mitochondrial tRNA aminoacylation, mitochondrial protein stability, and assembly and enzyme activities of OXPHOS complexes. Interestingly, by modeling FARS2 mutations associated with human disease in Drosophila, we provide evidence that expression of two human FARS2 variants, p.G309S and p.D142Y, induces seizure behaviors and locomotion defects, respectively. Together, our results not only show the relationship between dysfunction of mitochondrial aminoacylation system and pathologies, but also illustrate the application of Drosophila model for functional analysis of human disease-causing variants.
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Affiliation(s)
- Wenlu Fan
- Division of Human Reproduction and Developmental Genetics, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China.,Institute of Genetics, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang 310058, China.,Zhejiang Provincial Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310006, China
| | - Xiaoye Jin
- Division of Human Reproduction and Developmental Genetics, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China.,Institute of Genetics, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang 310058, China.,Zhejiang Provincial Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310006, China
| | - Man Xu
- Division of Human Reproduction and Developmental Genetics, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China.,Institute of Genetics, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang 310058, China.,Zhejiang Provincial Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310006, China
| | - Yongmei Xi
- Division of Human Reproduction and Developmental Genetics, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China.,Institute of Genetics, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang 310058, China
| | - Weiguo Lu
- Department of Gynecologic Oncology, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310006, China.,Cancer Center, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Xiaohang Yang
- Division of Human Reproduction and Developmental Genetics, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China.,Institute of Genetics, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang 310058, China.,Zhejiang Provincial Key Laboratory of Genetic and Developmental Disorders, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Min-Xin Guan
- Institute of Genetics, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang 310058, China.,Zhejiang Provincial Key Laboratory of Genetic and Developmental Disorders, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Wanzhong Ge
- Division of Human Reproduction and Developmental Genetics, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China.,Institute of Genetics, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang 310058, China.,Zhejiang Provincial Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310006, China.,Cancer Center, Zhejiang University, Hangzhou, Zhejiang 310058, China
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14
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Kapoor D, Majethia P, Anand A, Shukla A, Sharma S. Expanding the electro-clinical phenotype of CARS2associated neuroregression. Epilepsy Behav Rep 2021; 16:100485. [PMID: 34704010 PMCID: PMC8524140 DOI: 10.1016/j.ebr.2021.100485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 08/29/2021] [Accepted: 09/15/2021] [Indexed: 11/18/2022] Open
Abstract
Pathogenic variants in cysteinyl-tRNA synthetase-2 (CARS2) gene have recently been described to cause severe myoclonic epilepsy, neuroregression, progressive audio-visual impairment and movement disorder. We present an 11-year-old boy with neuroregression, dysfluent speech, aggressive behavior, tremors and ESES pattern on EEG Our case expands the existing electro-clinical phenotype of CARS2 associated neuroregression.
Biallelic variants in CARS2 (Cysteinyl-tRNA synthetase 2; MIM*612800), are known to cause combined oxidative phosphorylation deficiency 27 (MIM#616672), characterized by severe myoclonic epilepsy, neuroregression and complex movement disorders. To date, six individuals from five families have been reported with variants in CARS2. Herein, we present an 11-year-old boy who presented with neuroregression, dysfluent speech, aggressive behavior and tremors for 2 years. An electroencephalogram (EEG) revealed a highly abnormal background with generalized spike-and-wave discharges suggestive of Electrical Status Epilepticus during Sleep (ESES). A known homozygous c.655G > A(p.Ala219Thr) pathogenic variant in exon 6 of the CARS2(NM_024537.4) was identified on exome sequencing. Our report expands the electro-clinical spectrum of the phenotype with presence of severe behavioral abnormalities, continuous tremors and ESES pattern on EEG, not previously reported.
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Affiliation(s)
- Dipti Kapoor
- Neurology Division, Department of Pediatrics, Lady Hardinge Medical College and Associated Kalawati Saran Children's Hospital, India
| | - Purvi Majethia
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
| | - Aakanksha Anand
- Neurology Division, Department of Pediatrics, Lady Hardinge Medical College and Associated Kalawati Saran Children's Hospital, India
| | - Anju Shukla
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
| | - Suvasini Sharma
- Neurology Division, Department of Pediatrics, Lady Hardinge Medical College and Associated Kalawati Saran Children's Hospital, India
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15
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Ravel JM, Dreumont N, Mosca P, Smith DEC, Mendes MI, Wiedemann A, Coelho D, Schmitt E, Rivière JB, Tran Mau-Them F, Thevenon J, Kuentz P, Polivka M, Fuchs SA, Kok G, Thauvin-Robinet C, Guéant JL, Salomons GS, Faivre L, Feillet F. A bi-allelic loss-of-function SARS1 variant in children with neurodevelopmental delay, deafness, cardiomyopathy, and decompensation during fever. Hum Mutat 2021; 42:1576-1583. [PMID: 34570399 DOI: 10.1002/humu.24285] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 09/01/2021] [Accepted: 09/23/2021] [Indexed: 11/08/2022]
Abstract
Aminoacyl-tRNA synthetases (aaRS) are ubiquitously expressed enzymes responsible for ligating amino acids to their cognate tRNA molecules through an aminoacylation reaction. The resulting aminoacyl-tRNA is delivered to ribosome elongation factors to participate in protein synthesis. Seryl-tRNA synthetase (SARS1) is one of the cytosolic aaRSs and catalyzes serine attachment to tRNASer . SARS1 deficiency has already been associated with moderate intellectual disability, ataxia, muscle weakness, and seizure in one family. We describe here a new clinical presentation including developmental delay, central deafness, cardiomyopathy, and metabolic decompensation during fever leading to death, in a consanguineous Turkish family, with biallelic variants (c.638G>T, p.(Arg213Leu)) in SARS1. This missense variant was shown to lead to protein instability, resulting in reduced protein level and enzymatic activity. Our results describe a new clinical entity and expand the clinical and mutational spectrum of SARS1 and aaRS deficiencies.
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Affiliation(s)
- Jean-Marie Ravel
- Reference Centre of Inborn Metabolism Diseases, Université de Lorraine, CHRU-Nancy, Nancy, France.,NGERE, Université de Lorraine, Inserm, Nancy, France
| | | | - Pauline Mosca
- NGERE, Université de Lorraine, Inserm, Nancy, France
| | - Desiree E C Smith
- Metabolic Unit, Department of Clinical Chemistry, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Marisa I Mendes
- Metabolic Unit, Department of Clinical Chemistry, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | | | - David Coelho
- NGERE, Université de Lorraine, Inserm, Nancy, France
| | | | - Jean-Baptiste Rivière
- Unité Fonctionnelle Innovation en Diagnostic génomique des maladies rares, CHU Dijon Bourgogne, Dijon, France.,Centre de Génétique, Centre de Référence Anomalies du Développement et Syndromes Malformatifs, Centre de Compétence Maladies Mitochondriales, FHU TRANSLAD, Hôpital d'Enfants, CHU de Dijon, France.,INSERM UMR1231, Equipe Génétique des Anomalies du Développement, Université de Bourgogne, Dijon, France
| | - Frédéric Tran Mau-Them
- Unité Fonctionnelle Innovation en Diagnostic génomique des maladies rares, CHU Dijon Bourgogne, Dijon, France.,Centre de Génétique, Centre de Référence Anomalies du Développement et Syndromes Malformatifs, Centre de Compétence Maladies Mitochondriales, FHU TRANSLAD, Hôpital d'Enfants, CHU de Dijon, France.,INSERM UMR1231, Equipe Génétique des Anomalies du Développement, Université de Bourgogne, Dijon, France
| | - Julien Thevenon
- Unité Fonctionnelle Innovation en Diagnostic génomique des maladies rares, CHU Dijon Bourgogne, Dijon, France.,Centre de Génétique, Centre de Référence Anomalies du Développement et Syndromes Malformatifs, Centre de Compétence Maladies Mitochondriales, FHU TRANSLAD, Hôpital d'Enfants, CHU de Dijon, France.,INSERM UMR1231, Equipe Génétique des Anomalies du Développement, Université de Bourgogne, Dijon, France
| | - Paul Kuentz
- Centre de Génétique, Centre de Référence Anomalies du Développement et Syndromes Malformatifs, Centre de Compétence Maladies Mitochondriales, FHU TRANSLAD, Hôpital d'Enfants, CHU de Dijon, France.,INSERM UMR1231, Equipe Génétique des Anomalies du Développement, Université de Bourgogne, Dijon, France
| | - Marc Polivka
- Department of Pathology, Hôpital Lariboisière, Paris, France
| | - Sabine A Fuchs
- Department of Metabolic Diseases, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, The Netherlands.,Regenerative Medicine Center Utrecht, Regenerative Medicine Utrecht, Utrecht, The Netherlands.,On behalf of "United for Metabolic Diseases,", Amsterdam, the Netherlands
| | - Gautam Kok
- Department of Pathology, Hôpital Lariboisière, Paris, France
| | - Christel Thauvin-Robinet
- Unité Fonctionnelle Innovation en Diagnostic génomique des maladies rares, CHU Dijon Bourgogne, Dijon, France.,Centre de Génétique, Centre de Référence Anomalies du Développement et Syndromes Malformatifs, Centre de Compétence Maladies Mitochondriales, FHU TRANSLAD, Hôpital d'Enfants, CHU de Dijon, France.,INSERM UMR1231, Equipe Génétique des Anomalies du Développement, Université de Bourgogne, Dijon, France
| | - Jean-Louis Guéant
- Reference Centre of Inborn Metabolism Diseases, Université de Lorraine, CHRU-Nancy, Nancy, France.,NGERE, Université de Lorraine, Inserm, Nancy, France
| | - Gajja S Salomons
- Metabolic Unit, Department of Clinical Chemistry, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Laurence Faivre
- Centre de Génétique, Centre de Référence Anomalies du Développement et Syndromes Malformatifs, Centre de Compétence Maladies Mitochondriales, FHU TRANSLAD, Hôpital d'Enfants, CHU de Dijon, France.,INSERM UMR1231, Equipe Génétique des Anomalies du Développement, Université de Bourgogne, Dijon, France
| | - François Feillet
- Reference Centre of Inborn Metabolism Diseases, Université de Lorraine, CHRU-Nancy, Nancy, France.,NGERE, Université de Lorraine, Inserm, Nancy, France
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16
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Friederich MW, Geddes GC, Wortmann SB, Punnoose A, Wartchow E, Knight KM, Prokisch H, Creadon-Swindell G, Mayr JA, Van Hove JLK. Pathogenic variants in MRPL44 cause infantile cardiomyopathy due to a mitochondrial translation defect. Mol Genet Metab 2021; 133:362-371. [PMID: 34140213 PMCID: PMC8289749 DOI: 10.1016/j.ymgme.2021.06.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 06/03/2021] [Accepted: 06/04/2021] [Indexed: 11/22/2022]
Abstract
Cardiac dysfunction is a common phenotypic manifestation of primary mitochondrial disease with multiple nuclear and mitochondrial DNA pathogenic variants as a cause, including disorders of mitochondrial translation. To date, five patients have been described with pathogenic variants in MRPL44, encoding the ml44 protein which is part of the large subunit of the mitochondrial ribosome (mitoribosome). Three presented as infants with hypertrophic cardiomyopathy, mild lactic acidosis, and easy fatigue and muscle weakness, whereas two presented in adolescence with myopathy and neurological symptoms. We describe two infants who presented with cardiomyopathy from the neonatal period, failure to thrive, hypoglycemia and in one infant lactic acidosis. A decompensation of the cardiac function in the first year resulted in demise. Exome sequencing identified compound heterozygous variants in the MRPL44 gene including the known pathogenic variant c.467 T > G and two novel pathogenic variants. We document a combined respiratory chain enzyme deficiency with emphasis on complex I and IV, affecting heart muscle tissue more than skeletal muscle or fibroblasts. We show this to be caused by reduced mitochondrial DNA encoded protein synthesis affecting all subunits, and resulting in dysfunction of complex I and IV assembly. The degree of oxidative phosphorylation dysfunction correlated with the impairment of mitochondrial protein synthesis due to different pathogenic variants. These functional studies allow for improved understanding of the pathogenesis of MRPL44-associated mitochondrial disorder.
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Affiliation(s)
- Marisa W Friederich
- Department of Pediatrics, Section of Clinical Genetics and Metabolism, University of Colorado, Aurora, CO, USA; Department of Pathology and Laboratory Services, Children's Hospital Colorado, Aurora, CO, USA
| | - Gabrielle C Geddes
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI, USA; Department of Molecular and Medical Genetics, Indiana University, Indianapolis, IN, USA
| | - Saskia B Wortmann
- University Children's Hospital, Paracelsus Medical University (PMU), Salzburg, Austria; Amalia Children's Hospital, RadboudUMC, Nijmegen, the Netherlands
| | - Ann Punnoose
- Herma Heart Institute, Children's Hospital of Wisconsin, Milwaukee, WI, USA
| | - Eric Wartchow
- Department of Pathology and Laboratory Services, Children's Hospital Colorado, Aurora, CO, USA
| | - Kaz M Knight
- Department of Pediatrics, Section of Clinical Genetics and Metabolism, University of Colorado, Aurora, CO, USA
| | - Holger Prokisch
- Institute of Neurogenomics, Helmholtz Zentrum München, Neuherberg, Germany; Institute of Human Genetics, Technical University of Munich, Munich, Germany
| | | | - Johannes A Mayr
- University Children's Hospital, Paracelsus Medical University (PMU), Salzburg, Austria
| | - Johan L K Van Hove
- Department of Pediatrics, Section of Clinical Genetics and Metabolism, University of Colorado, Aurora, CO, USA; Department of Pathology and Laboratory Services, Children's Hospital Colorado, Aurora, CO, USA.
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17
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Rodrigo LM, Nyholt DR. Imputation and Reanalysis of ExomeChip Data Identifies Novel, Conditional and Joint Genetic Effects on Parkinson's Disease Risk. Genes (Basel) 2021; 12:genes12050689. [PMID: 34064523 PMCID: PMC8147919 DOI: 10.3390/genes12050689] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 04/22/2021] [Accepted: 04/30/2021] [Indexed: 12/12/2022] Open
Abstract
Given that improved imputation software and high-coverage whole genome sequence (WGS)-based haplotype reference panels now enable inexpensive approximation of WGS genotype data, we hypothesised that WGS-based imputation and analysis of existing ExomeChip-based genome-wide association (GWA) data will identify novel intronic and intergenic single nucleotide polymorphism (SNP) effects associated with complex disease risk. In this study, we reanalysed a Parkinson’s disease (PD) dataset comprising 5540 cases and 5862 controls genotyped using the ExomeChip-based NeuroX array. After genotype imputation and extensive quality control, GWA analysis was performed using PLINK and a recently developed machine learning approach (GenEpi), to identify novel, conditional and joint genetic effects associated with PD. In addition to improved validation of previously reported loci, we identified five novel genome-wide significant loci associated with PD: three (rs137887044, rs78837976 and rs117672332) with 0.01 < MAF < 0.05, and two (rs187989831 and rs12100172) with MAF < 0.01. Conditional analysis within genome-wide significant loci revealed four loci (p < 1 × 10−5) with multiple independent risk variants, while GenEpi analysis identified SNP–SNP interactions in seven genes. In addition to identifying novel risk loci for PD, these results demonstrate that WGS-based imputation and analysis of existing exome genotype data can identify novel intronic and intergenic SNP effects associated with complex disease risk.
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18
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Moseler A, Dhalleine T, Rouhier N, Couturier J. Arabidopsis thaliana 3-mercaptopyruvate sulfurtransferases interact with and are protected by reducing systems. J Biol Chem 2021; 296:100429. [PMID: 33609525 DOI: 10.1016/j.jbc.2021.100429] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 02/10/2021] [Accepted: 02/15/2021] [Indexed: 11/24/2022] Open
Abstract
The formation of a persulfide group (-SSH) on cysteine residues has gained attention as a reversible posttranslational modification contributing to protein regulation or protection. The widely distributed 3-mercaptopyruvate sulfurtransferases (MSTs) are implicated in the generation of persulfidated molecules and H2S biogenesis through transfer of a sulfane sulfur atom from a suitable donor to an acceptor. Arabidopsis has two MSTs, named STR1 and STR2, but they are poorly characterized. To learn more about these enzymes, we conducted a series of biochemical experiments including a variety of possible reducing systems. Our kinetic studies, which used a combination of sulfur donors and acceptors revealed that both MSTs use 3-mercaptopyruvate efficiently as a sulfur donor while thioredoxins, glutathione, and glutaredoxins all served as high-affinity sulfane sulfur acceptors. Using the redox-sensitive GFP (roGFP2) as a model acceptor protein, we showed that the persulfide-forming MSTs catalyze roGFP2 oxidation and more generally trans-persulfidation reactions. However, a preferential interaction with the thioredoxin system and glutathione was observed in case of competition between these sulfur acceptors. Moreover, we observed that MSTs are sensitive to overoxidation but are protected from an irreversible inactivation by their persulfide intermediate and subsequent reactivation by thioredoxins or glutathione. This work provides significant insights into Arabidopsis STR1 and STR2 catalytic properties and more specifically emphasizes the interaction with cellular reducing systems for the generation of H2S and glutathione persulfide and reactivation of an oxidatively modified form.
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19
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Jin X, Zhang Z, Nie Z, Wang C, Meng F, Yi Q, Chen M, Sun J, Zou J, Jiang P, Guan MX. An animal model for mitochondrial tyrosyl-tRNA synthetase deficiency reveals links between oxidative phosphorylation and retinal function. J Biol Chem 2021; 296:100437. [PMID: 33610547 PMCID: PMC8010715 DOI: 10.1016/j.jbc.2021.100437] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 02/09/2021] [Accepted: 02/16/2021] [Indexed: 12/13/2022] Open
Abstract
Mitochondria maintain a distinct pool of ribosomal machinery, including tRNAs and tRNAs activating enzymes, such as mitochondrial tyrosyl-tRNA synthetase (YARS2). Mutations in YARS2, which typically lead to the impairment of mitochondrial protein synthesis, have been linked to an array of human diseases including optic neuropathy. However, the lack of YARS2 mutation animal model makes us difficult to elucidate the pathophysiology underlying YARS2 deficiency. To explore this system, we generated YARS2 knockout (KO) HeLa cells and zebrafish using CRISPR/Cas9 technology. We observed the aberrant tRNATyr aminoacylation overall and reductions in the levels in mitochondrion- and nucleus-encoding subunits of oxidative phosphorylation system (OXPHOS), which were especially pronounced effects in the subunits of complex I and complex IV. These deficiencies manifested the decreased levels of intact supercomplexes overall. Immunoprecipitation assays showed that YARS2 bound to specific subunits of complex I and complex IV, suggesting the posttranslational stabilization of OXPHOS. Furthermore, YARS2 ablation caused defects in the stability and activities of OXPHOS complexes. These biochemical defects could be rescued by the overexpression of YARS2 cDNA in the YARS2KO cells. In zebrafish, the yars2KO larva conferred deficient COX activities in the retina, abnormal mitochondrial morphology, and numbers in the photoreceptor and retinal ganglion cells. The zebrafish further exhibited the retinal defects affecting both rods and cones. Vision defects in yars2KO zebrafish recapitulated the clinical phenotypes in the optic neuropathy patients carrying the YARS2 mutations. Our findings highlighted the critical role of YARS2 in the stability and activity of OXPHOS and its pathological consequence in vision impairments.
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Affiliation(s)
- Xiaofen Jin
- Key Laboratory of Reproductive Genetics, Ministry of Education of PRC, The Woman's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China; Division of Medical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine, and National Clinic Research Center for Child Health, Hangzhou, Zhejiang, China; Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Zengming Zhang
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Zhipeng Nie
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Chenghui Wang
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Feilong Meng
- Division of Medical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine, and National Clinic Research Center for Child Health, Hangzhou, Zhejiang, China; Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Qiuzi Yi
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Mengquan Chen
- Department of Lab Medicine, Wenzhou Hospital of Traditional Chinese Medicine, Wenzhou, Zhejiang, China
| | - Jiji Sun
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Jian Zou
- Insitute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Pingping Jiang
- Division of Medical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine, and National Clinic Research Center for Child Health, Hangzhou, Zhejiang, China; Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China; Zhejiang Provincial Key Laboratory of Genetic & Developmental Disorders, Zhejiang Univesity, Hangzhou, Zhejiang, China.
| | - Min-Xin Guan
- Key Laboratory of Reproductive Genetics, Ministry of Education of PRC, The Woman's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China; Division of Medical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine, and National Clinic Research Center for Child Health, Hangzhou, Zhejiang, China; Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China; Zhejiang Provincial Key Laboratory of Genetic & Developmental Disorders, Zhejiang Univesity, Hangzhou, Zhejiang, China; Division of Mitochondrial Biomedicine, Joint Institute of Genetics and Genome Medicine between Zhejiang University and University of Toronto, Hangzhou, Zhejiang, China.
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Kripps KA, Friederich MW, Chen T, Larson AA, Mirsky DM, Wang Y, Tanji K, Knight KM, Wong LJ, Van Hove JLK. A novel acceptor stem variant in mitochondrial tRNA Tyr impairs mitochondrial translation and is associated with a severe phenotype. Mol Genet Metab 2020; 131:398-404. [PMID: 33279411 PMCID: PMC7749820 DOI: 10.1016/j.ymgme.2020.11.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 11/13/2020] [Accepted: 11/13/2020] [Indexed: 11/25/2022]
Abstract
Genetic defects in mitochondrial DNA encoded tRNA genes impair mitochondrial translation with resultant defects in the mitochondrial respiratory chain and oxidative phosphorylation system. The phenotypic spectrum of disease seen in mitochondrial tRNA defects is variable and proving pathogenicity of new variants is challenging. Only three pathogenic variants have been described previously in the mitochondrial tRNATyr gene MT-TY, with the reported phenotypes consisting largely of adult onset myopathy and ptosis. We report a patient with a novel MT-TY acceptor stem variant m.5889A>G at high heteroplasmy in muscle, low in blood, and absent in the mother's blood. The phenotype consisted of a childhood-onset severe multi-system disorder characterized by a neurodegenerative course including ataxia and seizures, failure-to-thrive, combined myopathy and neuropathy, and hearing and vision loss. Brain imaging showed progressive atrophy and basal ganglia calcifications. Mitochondrial biomarkers lactate and GDF15 were increased. Functional studies showed a deficient activity of the respiratory chain enzyme complexes containing mtDNA-encoded subunits I, III and IV. There were decreased steady state levels of these mitochondrial complex proteins, and presence of incompletely assembled complex V forms in muscle. These changes are typical of a mitochondrial translational defect. These data support the pathogenicity of this novel variant. Careful review of variants in MT-TY additionally identified two other pathogenic variants, one likely pathogenic variant, nine variants of unknown significance, five likely benign and four benign variants.
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Affiliation(s)
- Kimberly A Kripps
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, CO, USA
| | - Marisa W Friederich
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, CO, USA; Department of Pathology and Laboratory Medicine, Children's Hospital Colorado, 13121 East 16th Avenue, Aurora, CO, USA
| | - Ting Chen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA; Department of Endocrinology, Genetics and Metabolism, Children's Hospital of Soochow University, Suzhou, China
| | - Austin A Larson
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, CO, USA
| | - David M Mirsky
- Department of Radiology, University of Colorado, and Children's Hospital Colorado, Aurora, CO, USA
| | - Yue Wang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Kurenai Tanji
- Division of Neuropathology, Columbia University Medical Center, New York, NY, USA
| | - Kaz M Knight
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, CO, USA
| | - Lee-Jun Wong
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Johan L K Van Hove
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, CO, USA; Department of Pathology and Laboratory Medicine, Children's Hospital Colorado, 13121 East 16th Avenue, Aurora, CO, USA.
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21
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Zuhra K, Tomé CS, Forte E, Vicente JB, Giuffrè A. The multifaceted roles of sulfane sulfur species in cancer-associated processes. Biochim Biophys Acta Bioenerg 2021; 1862:148338. [PMID: 33212042 DOI: 10.1016/j.bbabio.2020.148338] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 10/30/2020] [Accepted: 11/13/2020] [Indexed: 02/07/2023]
Abstract
Sulfane sulfur species comprise a variety of biologically relevant hydrogen sulfide (H2S)-derived species, including per- and poly-sulfidated low molecular weight compounds and proteins. A growing body of evidence suggests that H2S, currently recognized as a key signaling molecule in human physiology and pathophysiology, plays an important role in cancer biology by modulating cell bioenergetics and contributing to metabolic reprogramming. This is accomplished through functional modulation of target proteins via H2S binding to heme iron centers or H2S-mediated reversible per- or poly-sulfidation of specific cysteine residues. Since sulfane sulfur species are increasingly viewed not only as a major source of H2S but also as key mediators of some of the biological effects commonly attributed to H2S, the multifaceted role of these species in cancer biology is reviewed here with reference to H2S, focusing on their metabolism, signaling function, impact on cell bioenergetics and anti-tumoral properties.
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22
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Knight KM, Shelkowitz E, Larson AA, Mirsky DM, Wang Y, Chen T, Wong LJ, Friederich MW, Van Hove JLK. The mitochondrial DNA variant m.9032T > C in MT-ATP6 encoding p.(Leu169Pro) causes a complex mitochondrial neurological syndrome. Mitochondrion 2020; 55:8-13. [PMID: 32931937 DOI: 10.1016/j.mito.2020.08.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Revised: 07/09/2020] [Accepted: 08/31/2020] [Indexed: 12/13/2022]
Abstract
Diagnosing complex V deficiencies caused by new variants in mitochondrial DNA is challenging due to the rarity, phenotypic diversity, and limited functional assessments. We describe a child with the m.9032T > C variant in MT-ATP6 encoding p.(Leu169Pro), with primary presentation of microcephaly, ataxia, hearing loss, and lactic acidosis. Functional studies reveal abnormal fragment F1 of complex V on blue native gel electrophoresis. Respirometry showed excessively tight coupling through complex V depressing oxygen consumption upon ADP stimulation and an excessive increase following uncoupling, in the presence of upregulation of mitochondrial biogenesis. These data add evidence about pathogenicity and functional impact of this variant.
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Affiliation(s)
- Kaz M Knight
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, CO, USA
| | - Emily Shelkowitz
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, CO, USA
| | - Austin A Larson
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, CO, USA
| | - David M Mirsky
- Department of Radiology, University of Colorado, and Children's Hospital Colorado, Aurora, CO, USA
| | - Yue Wang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Ting Chen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA; Department of Endocrinology, Genetics and Metabolism, Children's Hospital of Soochow University, Suzhou, China
| | - Lee-Jun Wong
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Marisa W Friederich
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, CO, USA; Department of Pathology and Laboratory Medicine, Children's Hospital Colorado, 13121 East 16th Avenue, Aurora, CO, USA
| | - Johan L K Van Hove
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, CO, USA; Department of Pathology and Laboratory Medicine, Children's Hospital Colorado, 13121 East 16th Avenue, Aurora, CO, USA.
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Sawa T, Motohashi H, Ihara H, Akaike T. Enzymatic Regulation and Biological Functions of Reactive Cysteine Persulfides and Polysulfides. Biomolecules 2020; 10:E1245. [PMID: 32867265 DOI: 10.3390/biom10091245] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Revised: 08/15/2020] [Accepted: 08/25/2020] [Indexed: 01/15/2023] Open
Abstract
Cysteine persulfide (CysSSH) and cysteine polysulfides (CysSSnH, n > 1) are cysteine derivatives that have sulfane sulfur atoms bound to cysteine thiol. Advances in analytical methods that detect and quantify persulfides and polysulfides have shown that CysSSH and related species such as glutathione persulfide occur physiologically and are prevalent in prokaryotes, eukaryotes, and mammals in vivo. The chemical properties and abundance of these compounds suggest a central role for reactive persulfides in cell-regulatory processes. CysSSH and related species have been suggested to act as powerful antioxidants and cellular protectants and may serve as redox signaling intermediates. It was recently shown that cysteinyl-tRNA synthetase (CARS) is a new cysteine persulfide synthase. In addition, we discovered that CARS is involved in protein polysulfidation that is coupled with translation. Mitochondrial activity in biogenesis and bioenergetics is supported and upregulated by CysSSH derived from mitochondrial CARS. In this review article, we discuss the mechanisms of the biosynthesis of CysSSH and related persulfide species, with a particular focus on the roles of CARS. We also review the antioxidative and anti-inflammatory actions of persulfides.
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24
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Bennett J, Kerr M, Greenway SC, Friederich MW, Van Hove JL, Hittel D, Khan A. Improved lactate control with dichloroacetate in a case with severe neonatal lactic acidosis due to MTFMT mitochondrial translation disorder. Mol Genet Metab Rep 2020; 24:100616. [PMID: 32577402 PMCID: PMC7303673 DOI: 10.1016/j.ymgmr.2020.100616] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 05/20/2020] [Accepted: 05/21/2020] [Indexed: 01/17/2023] Open
Abstract
Mitochondrial methionyl-tRNA formyltransferase (MTFMT) is a nuclear-encoded gene that produces a protein involved in mitochondrial translation. MTFMT formylates a portion of Met-tRNAMet, which allows for translation initiation of mitochondrial mRNA. Mutations in this gene have been shown to result in decreased mitochondrial translation with reduction function of the electron transport chain complexes I, III, IV, and V, thus affecting cellular energy production. Our patient presented with severe lactic acidosis in the neonatal period, and was found to be homozygous for the pathogenic mutation c.994C > T, p.(Arg332*). Her blood lactate levels normalized and her cardiomyopathy reversed after initiation of dichloroacetate (30 mg/kg/day). After two years of follow-up, she continues to show long-term lactate stability, continues to make developmental gains, and is in overall good general health. This is the first report using dichloroacetate in a patient with MTFMT deficiency, which may be a potential therapeutic option that warrants further study.
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Affiliation(s)
- Jennifer Bennett
- Department of Medical Genetics and Pediatrics, Alberta Children's Hospital, Research Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Marina Kerr
- Department of Medical Genetics and Pediatrics, Alberta Children's Hospital, Research Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Steven C. Greenway
- Departments of Pediatrics, Cardiac Sciences, Biochemistry & Molecular Biology, Alberta Children's Hospital Research Institute, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Marisa W. Friederich
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, CO, USA
- Department of Pathology and Laboratory Medicine, Children's Hospital Colorado, Aurora, CO, USA
| | - Johan L.K. Van Hove
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, CO, USA
- Department of Pathology and Laboratory Medicine, Children's Hospital Colorado, Aurora, CO, USA
| | - Dustin Hittel
- Department of Biochemistry & Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Aneal Khan
- Department of Medical Genetics and Pediatrics, Alberta Children's Hospital, Research Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
- Corresponding author at: Alberta Children's Hospital, 28 Oki Drive NW, Calgary, Alberta T3B 6A8, Canada.
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25
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Wu TH, Peng J, Zhang CL, Wu LW, Yang LF, Peng P, Pang N, Yin F, He F. [Mutations in aminoacyl-tRNA synthetase genes: an analysis of 10 cases]. Zhongguo Dang Dai Er Ke Za Zhi 2020; 22:595-601. [PMID: 32571458 PMCID: PMC7390216 DOI: 10.7499/j.issn.1008-8830.1912040] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 04/26/2020] [Indexed: 06/11/2023]
Abstract
OBJECTIVE To study the clinical features of the diseases associated with aminoacyl-tRNA synthetases (ARS) deficiency. METHODS A retrospective analysis was performed of the clinical and gene mutation data of 10 children who were diagnosed with ARS gene mutations, based on next-generation sequencing from January 2016 to October 2019. RESULTS The age of onset ranged from 0 to 9 years among the 10 children. Convulsion was the most common initial symptom (7 children). Clinical manifestations included ataxia and normal or mildly retarded intellectual development (with or without epilepsy; n=4) and onset of epilepsy in childhood with developmental regression later (n=2). Some children experienced disease onset in the neonatal period and had severe epileptic encephalopathy, with myoclonus, generalized tonic-clonic seizure, and convulsive seizure (n=4); 3 had severe delayed development, 2 had feeding difficulty, and 1 had hearing impairment. Mutations were found in five genes: 3 had novel mutations in the AARS2 gene (c.331G>C, c.2682+5G>A, c.2164C>T, and c.761G>A), 2 had known mutations in the DARS2 gene (c.228-16C>A and c.536G>A), 1 had novel mutations in the CARS2 gene (c.1036C>T and c.323T>G), 1 had novel mutations in the RARS2 gene (c.1210A>G and c.622C>T), and 3 had novel mutations in the AARS gene (c.1901T>A, c.229C>T, c.244C>T, c.961G>C, c.2248C>T, and Chr16:70298860-70316687del). CONCLUSIONS A high heterogeneity is observed in the clinical phenotypes of the diseases associated with the ARS deficiency. A total of 14 novel mutations in 5 genes are reported in this study, which enriches the clinical phenotypes and genotypes of the diseases associated with ARS deficiency.
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Affiliation(s)
- Teng-Hui Wu
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha 410008, China.
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Friederich MW, Perez FA, Knight KM, Van Hove RA, Yang SP, Saneto RP, Van Hove JLK. Pathogenic variants in NUBPL result in failure to assemble the matrix arm of complex I and cause a complex leukoencephalopathy with thalamic involvement. Mol Genet Metab 2020; 129:236-242. [PMID: 31917109 PMCID: PMC8096346 DOI: 10.1016/j.ymgme.2019.12.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 12/27/2019] [Accepted: 12/29/2019] [Indexed: 01/16/2023]
Abstract
Disorders of the white matter are genetically very heterogeneous including several genes involved in mitochondrial bioenergetics. Diagnosis of the underlying cause is aided by pattern recognition on neuroimaging and by next-generation sequencing. Recently, genetic changes in the complex I assembly factor NUBPL have been characterized by a consistent recognizable pattern of leukoencephalopathy affecting deep white matter including the corpus callosum and cerebellum. Here, we report twin boys with biallelic variants in NUBPL, an unreported c.351 G > A; p.(Met117Ile) and a previously reported pathological variant c. 693 + 1 G > A. Brain magnetic resonance imaging showed abnormal T2 hyperintense signal involving the periventricular white matter, external capsule, corpus callosum, and, prominently, the bilateral thalami. The neuroimaging pattern evolved over 18 months with marked diffuse white matter signal abnormality, volume loss, and new areas of signal abnormality in the cerebellar folia and vermis. Magnetic resonance spectroscopy showed elevated lactate. Functional studies in cultured fibroblasts confirmed pathogenicity of the genetic variants. Complex I activity of the respiratory chain was deficient spectrophotometrically and on blue native gel with in-gel activity staining. There was absent assembly and loss of proteins of the matrix arm of complex I when traced with an antibody to NDUFS2, and incomplete assembly of the membrane arm when traced with an NDUFB6 antibody. There was decreased NUBPL protein on Western blot in patient fibroblasts compared to controls. Compromised NUBPL activity impairs assembly of the matrix arm of complex I and produces a severe, rapidly-progressive leukoencephalopathy with thalamic involvement on MRI, further expanding the neuroimaging phenotype.
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Affiliation(s)
- Marisa W Friederich
- Department of Pediatrics, Section of Clinical Genetics and Metabolism, University of Colorado, RC1-N P18-4404K, 12800 East 19th Avenue, Aurora, CO 80045, USA; Department of Pathology and Laboratory Medicine, Children's Hospital Colorado, 13121 East 16th Avenue, Aurora, CO 80045, USA
| | - Francisco A Perez
- Department of Radiology, Seattle Children's Hospital, University of Washington, 4800 Sand Point Way NE, Seattle, WA 98105, USA
| | - Kaz M Knight
- Department of Pediatrics, Section of Clinical Genetics and Metabolism, University of Colorado, RC1-N P18-4404K, 12800 East 19th Avenue, Aurora, CO 80045, USA
| | - Roxanne A Van Hove
- Department of Pediatrics, Section of Clinical Genetics and Metabolism, University of Colorado, RC1-N P18-4404K, 12800 East 19th Avenue, Aurora, CO 80045, USA
| | - Samuel P Yang
- Clinical Genomics and Preventative Medicine, Providence Medical Group, 105 West 8th Street 454-E, Spokane, WA 99204, USA
| | - Russell P Saneto
- Mitochondrial Medicine and Metabolism, Department of Neurology, Division of Pediatric Neurology, Seattle Children's Hospital, 4800 Sand Point Way NE, Seattle, WA 98105, USA; Center for Integrative Brain Research, Neuroscience Institute, 1900 Ninth Ave, Mailstop C9S-10, Seattle, WA 98101, USA
| | - Johan L K Van Hove
- Department of Pediatrics, Section of Clinical Genetics and Metabolism, University of Colorado, RC1-N P18-4404K, 12800 East 19th Avenue, Aurora, CO 80045, USA; Department of Pathology and Laboratory Medicine, Children's Hospital Colorado, 13121 East 16th Avenue, Aurora, CO 80045, USA.
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Froukh T, Nafie O, Al Hait SAS, Laugwitz L, Sommerfeld J, Sturm M, Baraghiti A, Issa T, Al-Nazer A, Koch PA, Hanselmann J, Kootz B, Bauer P, Al-Ameri W, Abou Jamra R, Alfrook AJ, Hamadallah M, Sofan L, Riess A, Haack TB, Riess O, Buchert R. Genetic basis of neurodevelopmental disorders in 103 Jordanian families. Clin Genet 2020; 97:621-627. [PMID: 32056211 DOI: 10.1111/cge.13720] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 01/15/2020] [Accepted: 02/05/2020] [Indexed: 10/25/2022]
Abstract
We recruited 103 families from Jordan with neurodevelopmental disorders (NDD) and patterns of inheritance mostly suggestive of autosomal recessive inheritance. In each family, we investigated at least one affected individual using exome sequencing and an in-house diagnostic variant interpretation pipeline including a search for copy number variation. This approach led us to identify the likely molecular defect in established disease genes in 37 families. We could identify 25 pathogenic nonsense and 11 missense variants as well as 3 pathogenic copy number variants and 1 repeat expansion. Notably, 11 of the disease-causal variants occurred de novo. In addition, we prioritized a homozygous frameshift variant in PUS3 in two sisters with intellectual disability. To our knowledge, PUS3 has been postulated only recently as a candidate disease gene for intellectual disability in a single family with three affected siblings. Our findings provide additional evidence to establish loss of PUS3 function as a cause of intellectual disability.
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Affiliation(s)
- Tawfiq Froukh
- Department of Biotechnology and Genetic Engineering, Philadelphia University, Amman, Jordan
| | - Omar Nafie
- Faculty of Medicine, Mutah University, Alkarak, Jordan
| | | | - Lucia Laugwitz
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Julia Sommerfeld
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Marc Sturm
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Aya Baraghiti
- Department of Biotechnology and Genetic Engineering, Philadelphia University, Amman, Jordan
| | - Tala Issa
- Department of Biotechnology and Genetic Engineering, Philadelphia University, Amman, Jordan
| | - Anis Al-Nazer
- Department of Biotechnology and Genetic Engineering, Philadelphia University, Amman, Jordan
| | - Philipp A Koch
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Johannes Hanselmann
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Beate Kootz
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Peter Bauer
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | | | - Rami Abou Jamra
- Institute of Human Genetics, University Medical Center Leipzig, Leipzig, Germany
| | | | | | - Linda Sofan
- Department of Biotechnology and Genetic Engineering, Philadelphia University, Amman, Jordan
| | - Angelika Riess
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Tobias B Haack
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Olaf Riess
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Rebecca Buchert
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
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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] [What about the content of this article? (0)] [Affiliation(s)] [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.
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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.
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29
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van der Veen S, Zutt R, Klein C, Marras C, Berkovic SF, Caviness JN, Shibasaki H, de Koning TJ, Tijssen MAJ. Nomenclature of Genetically Determined Myoclonus Syndromes: Recommendations of the International Parkinson and Movement Disorder Society Task Force. Mov Disord 2019; 34:1602-1613. [PMID: 31584223 PMCID: PMC6899848 DOI: 10.1002/mds.27828] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 07/09/2019] [Accepted: 07/24/2019] [Indexed: 12/12/2022] Open
Abstract
Genetically determined myoclonus disorders are a result of a large number of genes. They have wide clinical variation and no systematic nomenclature. With next-generation sequencing, genetic diagnostics require stringent criteria to associate genes and phenotype. To improve (future) classification and recognition of genetically determined movement disorders, the Movement Disorder Society Task Force for Nomenclature of Genetic Movement Disorders (2012) advocates and renews the naming system of locus symbols. Here, we propose a nomenclature for myoclonus syndromes and related disorders with myoclonic jerks (hyperekplexia and myoclonic epileptic encephalopathies) to guide clinicians in their diagnostic approach to patients with these disorders. Sixty-seven genes were included in the nomenclature. They were divided into 3 subgroups: prominent myoclonus syndromes, 35 genes; prominent myoclonus syndromes combined with another prominent movement disorder, 9 genes; disorders that present usually with other phenotypes but can manifest as a prominent myoclonus syndrome, 23 genes. An additional movement disorder is seen in nearly all myoclonus syndromes: ataxia (n = 41), ataxia and dystonia (n = 6), and dystonia (n = 5). However, no additional movement disorders were seen in related disorders. Cognitive decline and epilepsy are present in the vast majority. The anatomical origin of myoclonus is known in 64% of genetic disorders: cortical (n = 34), noncortical areas (n = 8), and both (n = 1). Cortical myoclonus is commonly seen in association with ataxia, and noncortical myoclonus is often seen with myoclonus-dystonia. This new nomenclature of myoclonus will guide diagnostic testing and phenotype classification. © 2019 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Sterre van der Veen
- Department of Neurology, University Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Rodi Zutt
- Department of Neurology, University Groningen, University Medical Center Groningen, Groningen, Netherlands.,Department of Neurology, Haga Teaching Hospital, The Hague, The Netherlands
| | - Christine Klein
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
| | - Connie Marras
- Edmond J. Safra Program in Parkinson's Disease, Toronto Western Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Samuel F Berkovic
- Epilepsy Research Center, Department of Medicine, University of Melbourne, Austin Health, Heidelberg, Victoria, Australia
| | - John N Caviness
- Department of Neurology, Mayo Clinic, Scottsdale, Arizona, USA
| | | | - Tom J de Koning
- Department of Neurology, University Groningen, University Medical Center Groningen, Groningen, Netherlands.,Department of Genetics, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands
| | - Marina A J Tijssen
- Department of Neurology, University Groningen, University Medical Center Groningen, Groningen, Netherlands
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Srivastava S, Butala A, Mahida S, Richter J, Mu W, Poretti A, Vernon H, VanGerpen J, Atwal PS, Middlebrooks EH, Zee DS, Naidu S. Expansion of the clinical spectrum associated with AARS2-related disorders. Am J Med Genet A 2019; 179:1556-1564. [PMID: 31099476 DOI: 10.1002/ajmg.a.61188] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 04/21/2019] [Accepted: 04/23/2019] [Indexed: 12/14/2022]
Abstract
Biallelic pathogenic variants in AARS2, a gene encoding the mitochondrial alanyl-tRNA synthetase, result in a spectrum of findings ranging from infantile cardiomyopathy to adult-onset progressive leukoencephalopathy. In this article, we present three unrelated individuals with novel compound heterozygous pathogenic AARS2 variants underlying diverse clinical presentations. Patient 1 is a 51-year-old man with adult-onset progressive cognitive, psychiatric, and motor decline and leukodystrophy. Patient 2 is a 34-year-old man with childhood-onset progressive tremor followed by the development of polyneuropathy, ataxia, and mild cognitive and psychiatric decline without leukodystrophy on imaging. Patient 3 is a 57-year-old woman with childhood-onset tremor and nystagmus which preceded dystonia, chorea, ataxia, depression, and cognitive decline marked by cerebellar atrophy and white matter disease. These cases expand the clinical heterogeneity of AARS2-related disorders, given that the first and third case represent some of the oldest known survivors of this disease, the second is adult-onset AARS2-related neurological decline without leukodystrophy, and the third is biallelic AARS2-related disorder involving a partial gene deletion.
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Affiliation(s)
| | - Ankur Butala
- Department of Neurology, The Johns Hopkins Hospital, Baltimore, Maryland
| | - Sonal Mahida
- Department of Neurology, Boston Children's Hospital, Boston, Massachusetts
| | - John Richter
- Department of Neurology, Mayo Clinic, Jacksonville, Florida
| | - Weiyi Mu
- Institute of Genetic Medicine, The Johns Hopkins Hospital, Baltimore, Maryland
| | - Andrea Poretti
- Department of Neurogenetics, Hugo W. Moser Research Institute at Kennedy Krieger Institute, Baltimore, Maryland.,Department of Neurology and Pediatrics, The Johns Hopkins Hospital, Baltimore, Maryland
| | - Hilary Vernon
- Institute of Genetic Medicine, The Johns Hopkins Hospital, Baltimore, Maryland
| | - Jay VanGerpen
- Department of Neurology, Mayo Clinic, Jacksonville, Florida
| | | | - Erik H Middlebrooks
- Department of Radiology and Neurosurgery, Mayo Clinic, Jacksonville, Florida
| | - David S Zee
- Department of Neurology, The Johns Hopkins Hospital, Baltimore, Maryland.,Department of Ophthalmology, Otolaryngology, Head and Neck Surgery and Neuroscience, The Johns Hopkins Hospital, Baltimore, Maryland
| | - SakkuBai Naidu
- Department of Neurogenetics, Hugo W. Moser Research Institute at Kennedy Krieger Institute, Baltimore, Maryland.,Department of Neurology and Pediatrics, The Johns Hopkins Hospital, Baltimore, Maryland
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31
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Newell C, Khan A, Sinasac D, Shoffner J, Friederich MW, Van Hove JLK, Hume S, Shearer J, Sosova I. Hybrid gel electrophoresis using skin fibroblasts to aid in diagnosing mitochondrial disease. Neurol Genet 2019; 5:e336. [PMID: 31192304 PMCID: PMC6515941 DOI: 10.1212/nxg.0000000000000336] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 02/08/2019] [Accepted: 03/01/2019] [Indexed: 12/26/2022]
Abstract
Objective We developed a novel, hybrid method combining both blue-native (BN-PAGE) and clear-native (CN-PAGE) polyacrylamide gel electrophoresis, termed BCN-PAGE, to perform in-gel activity stains on the mitochondrial electron transport chain (ETC) complexes in skin fibroblasts. Methods Four patients aged 46–65 years were seen in the Metabolic Clinic at Alberta Children's Hospital and investigated for mitochondrial disease and had BN-PAGE or CN-PAGE on skeletal muscle that showed incomplete assembly of complex V (CV) in each patient. Long-range PCR performed on muscle-extracted DNA identified 4 unique mitochondrial DNA (mtDNA) deletions spanning the ATP6 gene of CV. We developed a BCN-PAGE method in skin fibroblasts taken from the patients at the same time and compared the findings with those in skeletal muscle. Results In all 4 cases, BCN-PAGE in skin fibroblasts confirmed the abnormal CV activity found from muscle biopsy, suggesting that the mtDNA deletions involving ATP6 were most likely germline mutations that are associated with a clinical phenotype of mitochondrial disease. Conclusions The BCN-PAGE method in skin fibroblasts has a potential to be a less-invasive tool compared with muscle biopsy to screen patients for abnormalities in CV and other mitochondrial ETC complexes.
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Affiliation(s)
- Christopher Newell
- Department of Medical Genetics (C.N., A.K., D.S.) and Department of Pediatrics (A.K.), Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Canada; Atlanta (J. Shoffner), GA; Departments of Pediatrics (M.W.F., J.L.K.V.H.), Section of Clinical Genetics and Metabolism, University of Colorado; Department of Medical Genetics (S.H.), University of Alberta, Canada; Faculty of Kinesiology (J. Shearer), University of Calgary, Alberta, Canada; and Departments of Laboratory Medicine and Pathology (I.S.), University of Alberta, Edmonton, Canada
| | - Aneal Khan
- Department of Medical Genetics (C.N., A.K., D.S.) and Department of Pediatrics (A.K.), Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Canada; Atlanta (J. Shoffner), GA; Departments of Pediatrics (M.W.F., J.L.K.V.H.), Section of Clinical Genetics and Metabolism, University of Colorado; Department of Medical Genetics (S.H.), University of Alberta, Canada; Faculty of Kinesiology (J. Shearer), University of Calgary, Alberta, Canada; and Departments of Laboratory Medicine and Pathology (I.S.), University of Alberta, Edmonton, Canada
| | - David Sinasac
- Department of Medical Genetics (C.N., A.K., D.S.) and Department of Pediatrics (A.K.), Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Canada; Atlanta (J. Shoffner), GA; Departments of Pediatrics (M.W.F., J.L.K.V.H.), Section of Clinical Genetics and Metabolism, University of Colorado; Department of Medical Genetics (S.H.), University of Alberta, Canada; Faculty of Kinesiology (J. Shearer), University of Calgary, Alberta, Canada; and Departments of Laboratory Medicine and Pathology (I.S.), University of Alberta, Edmonton, Canada
| | - John Shoffner
- Department of Medical Genetics (C.N., A.K., D.S.) and Department of Pediatrics (A.K.), Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Canada; Atlanta (J. Shoffner), GA; Departments of Pediatrics (M.W.F., J.L.K.V.H.), Section of Clinical Genetics and Metabolism, University of Colorado; Department of Medical Genetics (S.H.), University of Alberta, Canada; Faculty of Kinesiology (J. Shearer), University of Calgary, Alberta, Canada; and Departments of Laboratory Medicine and Pathology (I.S.), University of Alberta, Edmonton, Canada
| | - Marisa W Friederich
- Department of Medical Genetics (C.N., A.K., D.S.) and Department of Pediatrics (A.K.), Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Canada; Atlanta (J. Shoffner), GA; Departments of Pediatrics (M.W.F., J.L.K.V.H.), Section of Clinical Genetics and Metabolism, University of Colorado; Department of Medical Genetics (S.H.), University of Alberta, Canada; Faculty of Kinesiology (J. Shearer), University of Calgary, Alberta, Canada; and Departments of Laboratory Medicine and Pathology (I.S.), University of Alberta, Edmonton, Canada
| | - Johan L K Van Hove
- Department of Medical Genetics (C.N., A.K., D.S.) and Department of Pediatrics (A.K.), Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Canada; Atlanta (J. Shoffner), GA; Departments of Pediatrics (M.W.F., J.L.K.V.H.), Section of Clinical Genetics and Metabolism, University of Colorado; Department of Medical Genetics (S.H.), University of Alberta, Canada; Faculty of Kinesiology (J. Shearer), University of Calgary, Alberta, Canada; and Departments of Laboratory Medicine and Pathology (I.S.), University of Alberta, Edmonton, Canada
| | - Stacey Hume
- Department of Medical Genetics (C.N., A.K., D.S.) and Department of Pediatrics (A.K.), Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Canada; Atlanta (J. Shoffner), GA; Departments of Pediatrics (M.W.F., J.L.K.V.H.), Section of Clinical Genetics and Metabolism, University of Colorado; Department of Medical Genetics (S.H.), University of Alberta, Canada; Faculty of Kinesiology (J. Shearer), University of Calgary, Alberta, Canada; and Departments of Laboratory Medicine and Pathology (I.S.), University of Alberta, Edmonton, Canada
| | - Jane Shearer
- Department of Medical Genetics (C.N., A.K., D.S.) and Department of Pediatrics (A.K.), Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Canada; Atlanta (J. Shoffner), GA; Departments of Pediatrics (M.W.F., J.L.K.V.H.), Section of Clinical Genetics and Metabolism, University of Colorado; Department of Medical Genetics (S.H.), University of Alberta, Canada; Faculty of Kinesiology (J. Shearer), University of Calgary, Alberta, Canada; and Departments of Laboratory Medicine and Pathology (I.S.), University of Alberta, Edmonton, Canada
| | - Iveta Sosova
- Department of Medical Genetics (C.N., A.K., D.S.) and Department of Pediatrics (A.K.), Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Canada; Atlanta (J. Shoffner), GA; Departments of Pediatrics (M.W.F., J.L.K.V.H.), Section of Clinical Genetics and Metabolism, University of Colorado; Department of Medical Genetics (S.H.), University of Alberta, Canada; Faculty of Kinesiology (J. Shearer), University of Calgary, Alberta, Canada; and Departments of Laboratory Medicine and Pathology (I.S.), University of Alberta, Edmonton, Canada
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32
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González-Serrano LE, Chihade JW, Sissler M. When a common biological role does not imply common disease outcomes: Disparate pathology linked to human mitochondrial aminoacyl-tRNA synthetases. J Biol Chem 2019; 294:5309-5320. [PMID: 30647134 PMCID: PMC6462531 DOI: 10.1074/jbc.rev118.002953] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Mitochondrial aminoacyl-tRNA synthetases (mt-aaRSs) are essential components of the mitochondrial translation machinery. The correlation of mitochondrial disorders with mutations in these enzymes has raised the interest of the scientific community over the past several years. Most surprising has been the wide-ranging presentation of clinical manifestations in patients with mt-aaRS mutations, despite the enzymes' common biochemical role. Even among cases where a common physiological system is affected, phenotypes, severity, and age of onset varies depending on which mt-aaRS is mutated. Here, we review work done thus far and propose a categorization of diseases based on tissue specificity that highlights emerging patterns. We further discuss multiple in vitro and in cellulo efforts to characterize the behavior of WT and mutant mt-aaRSs that have shaped hypotheses about the molecular causes of these pathologies. Much remains to do in order to complete our understanding of these proteins. We expect that futher work is likely to result in the discovery of new roles for the mt-aaRSs in addition to their fundamental function in mitochondrial translation, informing the development of treatment strategies and diagnoses.
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Affiliation(s)
- Ligia Elena González-Serrano
- From the Université de Strasbourg, CNRS, Architecture et Réactivité de l'ARN, UPR9002, F-67000 Strasbourg, France and
| | - Joseph W Chihade
- the Department of Chemistry, Carleton College, Northfield, Minnesota 55057
| | - Marie Sissler
- From the Université de Strasbourg, CNRS, Architecture et Réactivité de l'ARN, UPR9002, F-67000 Strasbourg, France and
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Kuo ME, Theil AF, Kievit A, Malicdan MC, Introne WJ, Christian T, Verheijen FW, Smith DEC, Mendes MI, Hussaarts-Odijk L, van der Meijden E, van Slegtenhorst M, Wilke M, Vermeulen W, Raams A, Groden C, Shimada S, Meyer-Schuman R, Hou YM, Gahl WA, Antonellis A, Salomons GS, Mancini GMS. Cysteinyl-tRNA Synthetase Mutations Cause a Multi-System, Recessive Disease That Includes Microcephaly, Developmental Delay, and Brittle Hair and Nails. Am J Hum Genet 2019; 104:520-529. [PMID: 30824121 DOI: 10.1016/j.ajhg.2019.01.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 01/15/2019] [Indexed: 02/06/2023] Open
Abstract
Aminoacyl-tRNA synthetases (ARSs) are essential enzymes responsible for charging tRNA molecules with cognate amino acids. Consistent with the essential function and ubiquitous expression of ARSs, mutations in 32 of the 37 ARS-encoding loci cause severe, early-onset recessive phenotypes. Previous genetic and functional data suggest a loss-of-function mechanism; however, our understanding of the allelic and locus heterogeneity of ARS-related disease is incomplete. Cysteinyl-tRNA synthetase (CARS) encodes the enzyme that charges tRNACys with cysteine in the cytoplasm. To date, CARS variants have not been implicated in any human disease phenotype. Here, we report on four subjects from three families with complex syndromes that include microcephaly, developmental delay, and brittle hair and nails. Each affected person carries bi-allelic CARS variants: one individual is compound heterozygous for c.1138C>T (p.Gln380∗) and c.1022G>A (p.Arg341His), two related individuals are compound heterozygous for c.1076C>T (p.Ser359Leu) and c.1199T>A (p.Leu400Gln), and one individual is homozygous for c.2061dup (p.Ser688Glnfs∗2). Measurement of protein abundance, yeast complementation assays, and assessments of tRNA charging indicate that each CARS variant causes a loss-of-function effect. Compared to subjects with previously reported ARS-related diseases, individuals with bi-allelic CARS variants are unique in presenting with a brittle-hair-and-nail phenotype, which most likely reflects the high cysteine content in human keratins. In sum, our efforts implicate CARS variants in human inherited disease, expand the locus and clinical heterogeneity of ARS-related clinical phenotypes, and further support impaired tRNA charging as the primary mechanism of recessive ARS-related disease.
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Affiliation(s)
- Molly E Kuo
- Cellular and Molecular Biology Program, University of Michigan Medical School, Ann Arbor, MI 48109, USA; Medical Scientist Training Program, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Arjan F Theil
- Department of Molecular Genetics, Oncode Institute, Erasmus Medical Center, University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015 CN Rotterdam, the Netherlands
| | - Anneke Kievit
- Department of Clinical Genetics, Erasmus Medical Center, University Medical Center, 3015 GD Rotterdam, the Netherlands
| | - May Christine Malicdan
- Undiagnosed Diseases Program and Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Wendy J Introne
- Undiagnosed Diseases Program and Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Thomas Christian
- Department of Biochemistry and Molecular Biochemistry, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Frans W Verheijen
- Department of Clinical Genetics, Erasmus Medical Center, University Medical Center, 3015 GD Rotterdam, the Netherlands
| | - Desiree E C Smith
- Metabolic Unit, Department of Clinical Chemistry, Amsterdam University Medical Center and Amsterdam Gastroenterology and Metabolism, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, 1081 HZ Amsterdam, the Netherlands
| | - Marisa I Mendes
- Metabolic Unit, Department of Clinical Chemistry, Amsterdam University Medical Center and Amsterdam Gastroenterology and Metabolism, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, 1081 HZ Amsterdam, the Netherlands
| | - Lidia Hussaarts-Odijk
- Department of Clinical Genetics, Erasmus Medical Center, University Medical Center, 3015 GD Rotterdam, the Netherlands
| | - Eric van der Meijden
- Department of Clinical Genetics, Erasmus Medical Center, University Medical Center, 3015 GD Rotterdam, the Netherlands
| | - Marjon van Slegtenhorst
- Department of Clinical Genetics, Erasmus Medical Center, University Medical Center, 3015 GD Rotterdam, the Netherlands
| | - Martina Wilke
- Department of Clinical Genetics, Erasmus Medical Center, University Medical Center, 3015 GD Rotterdam, the Netherlands
| | - Wim Vermeulen
- Department of Molecular Genetics, Oncode Institute, Erasmus Medical Center, University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015 CN Rotterdam, the Netherlands
| | - Anja Raams
- Department of Molecular Genetics, Oncode Institute, Erasmus Medical Center, University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015 CN Rotterdam, the Netherlands
| | - Catherine Groden
- Undiagnosed Diseases Program and Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Shino Shimada
- Undiagnosed Diseases Program and Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Rebecca Meyer-Schuman
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Ya Ming Hou
- Department of Biochemistry and Molecular Biochemistry, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - William A Gahl
- Undiagnosed Diseases Program and Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Anthony Antonellis
- Cellular and Molecular Biology Program, University of Michigan Medical School, Ann Arbor, MI 48109, USA; 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.
| | - Gajja S Salomons
- Metabolic Unit, Department of Clinical Chemistry, Amsterdam University Medical Center and Amsterdam Gastroenterology and Metabolism, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, 1081 HZ Amsterdam, the Netherlands; Genetic Metabolic Diseases, Amsterdam University Medical Center, University of Amsterdam, 1081 HZ Amsterdam, the Netherlands.
| | - Grazia M S Mancini
- Department of Clinical Genetics, Erasmus Medical Center, University Medical Center, 3015 GD Rotterdam, the Netherlands
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Friedman J, Smith DE, Issa MY, Stanley V, Wang R, Mendes MI, Wright MS, Wigby K, Hildreth A, Crawford JR, Koehler AE, Chowdhury S, Nahas S, Zhai L, Xu Z, Lo WS, James KN, Musaev D, Accogli A, Guerrero K, Tran LT, Omar TEI, Ben-Omran T, Dimmock D, Kingsmore SF, Salomons GS, Zaki MS, Bernard G, Gleeson JG. Biallelic mutations in valyl-tRNA synthetase gene VARS are associated with a progressive neurodevelopmental epileptic encephalopathy. Nat Commun 2019; 10:707. [PMID: 30755602 DOI: 10.1038/s41467-018-07067-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 10/03/2018] [Indexed: 12/27/2022] Open
Abstract
Aminoacyl-tRNA synthetases (ARSs) function to transfer amino acids to cognate tRNA molecules, which are required for protein translation. To date, biallelic mutations in 31 ARS genes are known to cause recessive, early-onset severe multi-organ diseases. VARS encodes the only known valine cytoplasmic-localized aminoacyl-tRNA synthetase. Here, we report seven patients from five unrelated families with five different biallelic missense variants in VARS. Subjects present with a range of global developmental delay, epileptic encephalopathy and primary or progressive microcephaly. Longitudinal assessment demonstrates progressive cortical atrophy and white matter volume loss. Variants map to the VARS tRNA binding domain and adjacent to the anticodon domain, and disrupt highly conserved residues. Patient primary cells show intact VARS protein but reduced enzymatic activity, suggesting partial loss of function. The implication of VARS in pediatric neurodegeneration broadens the spectrum of human diseases due to mutations in tRNA synthetase genes.
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Accogli A, Guerrero K, D'Agostino MD, Tran L, Cieuta-Walti C, Thiffault I, Chénier S, Schwartzentruber J, Majewski J, Bernard G. Biallelic Loss-of-Function Variants in AIMP1 Cause a Rare Neurodegenerative Disease. J Child Neurol 2019; 34:74-80. [PMID: 30486714 DOI: 10.1177/0883073818811223] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
AIMP1/p43, is a noncatalytic component of the mammalian multi-tRNA synthetase complex that catalyzes the ligation of amino acids to their cognate tRNAs. AIMP1 is largely expressed in the central nervous system, where it is part of the regulatory machine of the neurofilament assembly, playing a crucial role in neuronal development and function. To date, nonsense mutations in AIMP1 have been associated with a primary neurodegenerative disorder consisting of cerebral atrophy, hypomyelination, microcephaly and epilepsy, whereas missense mutations have recently been linked to intellectual disability without neurodegeneration. Here, we report the first French-Canadian patient with a novel frameshift AIMP1 homozygous mutation (c.191_192delAA, p.Gln64Argfs*25), resulting in a severe neurodegenerative phenotype. We review and discuss the phenotypic spectrum associated with AIMP1 pathogenic variants.
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Affiliation(s)
- Andrea Accogli
- 1 Departments of Neurology and Neurosurgery, Pediatrics and Human Genetics, McGill University, Montreal, Canada.,2 UOC Neurochirurgia, Istituto Giannina Gaslini, Genova, Italy.,3 Università degli Studi di Genova, Genoa, Italy
| | - Kether Guerrero
- 1 Departments of Neurology and Neurosurgery, Pediatrics and Human Genetics, McGill University, Montreal, Canada.,4 Department of Internal Medicine, Division of Medical Genetics, McGill University Health Center, Montreal, Canada.,5 Child Health and Human Development Program, Research Institute of the McGill University Health Center, Montreal, Canada
| | - Maria Daniela D'Agostino
- 4 Department of Internal Medicine, Division of Medical Genetics, McGill University Health Center, Montreal, Canada.,6 Department of Human Genetics, McGill University, Montreal, Canada
| | - Luan Tran
- 1 Departments of Neurology and Neurosurgery, Pediatrics and Human Genetics, McGill University, Montreal, Canada.,4 Department of Internal Medicine, Division of Medical Genetics, McGill University Health Center, Montreal, Canada.,5 Child Health and Human Development Program, Research Institute of the McGill University Health Center, Montreal, Canada
| | - Cécile Cieuta-Walti
- 7 Service de Neuropédiatre, Université de Sherbrooke, Quebec, Canada.,8 Institut Lejeune, Paris, France
| | - Isabelle Thiffault
- 9 Center for Pediatric Genomic Medicine, Children's Mercy Hospital, Kansas City, MO, USA.,10 University of Missouri-Kansas City School of Medicine, Kansas City, MO, USA
| | - Sébastien Chénier
- 11 Department of Pediatrics, Division of Medical Genetics, Centre Hospitalier Universitaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, Canada
| | | | - Jacek Majewski
- 6 Department of Human Genetics, McGill University, Montreal, Canada
| | | | - Geneviève Bernard
- 1 Departments of Neurology and Neurosurgery, Pediatrics and Human Genetics, McGill University, Montreal, Canada.,4 Department of Internal Medicine, Division of Medical Genetics, McGill University Health Center, Montreal, Canada.,5 Child Health and Human Development Program, Research Institute of the McGill University Health Center, Montreal, Canada
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Zhou Z, Austin GL, Young LEA, Johnson LA, Sun R. Mitochondrial Metabolism in Major Neurological Diseases. Cells 2018; 7:E229. [PMID: 30477120 PMCID: PMC6316877 DOI: 10.3390/cells7120229] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 11/19/2018] [Accepted: 11/21/2018] [Indexed: 01/18/2023] Open
Abstract
Mitochondria are bilayer sub-cellular organelles that are an integral part of normal cellular physiology. They are responsible for producing the majority of a cell's ATP, thus supplying energy for a variety of key cellular processes, especially in the brain. Although energy production is a key aspect of mitochondrial metabolism, its role extends far beyond energy production to cell signaling and epigenetic regulation⁻functions that contribute to cellular proliferation, differentiation, apoptosis, migration, and autophagy. Recent research on neurological disorders suggest a major metabolic component in disease pathophysiology, and mitochondria have been shown to be in the center of metabolic dysregulation and possibly disease manifestation. This review will discuss the basic functions of mitochondria and how alterations in mitochondrial activity lead to neurological disease progression.
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Affiliation(s)
- Zhengqiu Zhou
- Molecular & Cellular Biochemistry Department, University of Kentucky, Lexington, KY 40536, USA.
| | - Grant L Austin
- Molecular & Cellular Biochemistry Department, University of Kentucky, Lexington, KY 40536, USA.
| | - Lyndsay E A Young
- Molecular & Cellular Biochemistry Department, University of Kentucky, Lexington, KY 40536, USA.
| | - Lance A Johnson
- Department of Physiology, University of Kentucky, Lexington, KY 40536, USA.
| | - Ramon Sun
- Molecular & Cellular Biochemistry Department, University of Kentucky, Lexington, KY 40536, USA.
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McLachlan F, Sires AM, Abbott CM. The role of translation elongation factor eEF1 subunits in neurodevelopmental disorders. Hum Mutat 2018; 40:131-141. [PMID: 30370994 DOI: 10.1002/humu.23677] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 10/16/2018] [Accepted: 10/23/2018] [Indexed: 11/06/2022]
Abstract
The multi-subunit eEF1 complex plays a crucial role in de novo protein synthesis. The central functional component of the complex is eEF1A, which occurs as two independently encoded variants with reciprocal expression patterns: whilst eEF1A1 is widely expressed, eEF1A2 is found only in neurons and muscle. Heterozygous mutations in the gene encoding eEF1A2, EEF1A2, have recently been shown to cause epilepsy, autism, and intellectual disability. The remaining subunits of the eEF1 complex, eEF1Bα, eEF1Bδ, eEF1Bγ, and valyl-tRNA synthetase (VARS), together form the GTP exchange factor for eEF1A and are ubiquitously expressed, in keeping with their housekeeping role. However, mutations in the genes encoding these subunits EEF1B2 (eEF1Bα), EEF1D (eEF1Bδ), and VARS (valyl-tRNA synthetase) have also now been identified as causes of neurodevelopmental disorders. In this review, we describe the mutations identified so far in comparison with the degree of normal variation in each gene, and the predicted consequences of the mutations on the functions of the proteins and their isoforms. We discuss the likely effects of the mutations in the context of the role of protein synthesis in neuronal development.
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Affiliation(s)
- Fiona McLachlan
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Molecular Medicine, The University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh, UK
| | - Anna Martinez Sires
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Molecular Medicine, The University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh, UK
| | - Catherine M Abbott
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Molecular Medicine, The University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh, UK
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Friederich MW, Timal S, Powell CA, Dallabona C, Kurolap A, Palacios-Zambrano S, Bratkovic D, Derks TGJ, Bick D, Bouman K, Chatfield KC, Damouny-Naoum N, Dishop MK, Falik-Zaccai TC, Fares F, Fedida A, Ferrero I, Gallagher RC, Garesse R, Gilberti M, González C, Gowan K, Habib C, Halligan RK, Kalfon L, Knight K, Lefeber D, Mamblona L, Mandel H, Mory A, Ottoson J, Paperna T, Pruijn GJM, Rebelo-Guiomar PF, Saada A, Sainz B, Salvemini H, Schoots MH, Smeitink JA, Szukszto MJ, Ter Horst HJ, van den Brandt F, van Spronsen FJ, Veltman JA, Wartchow E, Wintjes LT, Zohar Y, Fernández-Moreno MA, Baris HN, Donnini C, Minczuk M, Rodenburg RJ, Van Hove JLK. Pathogenic variants in glutamyl-tRNA Gln amidotransferase subunits cause a lethal mitochondrial cardiomyopathy disorder. Nat Commun 2018; 9:4065. [PMID: 30283131 PMCID: PMC6170436 DOI: 10.1038/s41467-018-06250-w] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 08/23/2018] [Indexed: 11/09/2022] Open
Abstract
Mitochondrial protein synthesis requires charging a mitochondrial tRNA with its amino acid. Here, the authors describe pathogenic variants in the GatCAB protein complex genes required for the generation of glutaminyl-mt-tRNAGln, that impairs mitochondrial translation and presents with cardiomyopathy. Mitochondrial protein synthesis requires charging mt-tRNAs with their cognate amino acids by mitochondrial aminoacyl-tRNA synthetases, with the exception of glutaminyl mt-tRNA (mt-tRNAGln). mt-tRNAGln is indirectly charged by a transamidation reaction involving the GatCAB aminoacyl-tRNA amidotransferase complex. Defects involving the mitochondrial protein synthesis machinery cause a broad spectrum of disorders, with often fatal outcome. Here, we describe nine patients from five families with genetic defects in a GatCAB complex subunit, including QRSL1, GATB, and GATC, each showing a lethal metabolic cardiomyopathy syndrome. Functional studies reveal combined respiratory chain enzyme deficiencies and mitochondrial dysfunction. Aminoacylation of mt-tRNAGln and mitochondrial protein translation are deficient in patients’ fibroblasts cultured in the absence of glutamine but restore in high glutamine. Lentiviral rescue experiments and modeling in S. cerevisiae homologs confirm pathogenicity. Our study completes a decade of investigations on mitochondrial aminoacylation disorders, starting with DARS2 and ending with the GatCAB complex.
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Affiliation(s)
- Marisa W Friederich
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, 80045, CO, USA
| | - Sharita Timal
- Radboud Center for Mitochondrial Medicine, Translational Metabolic Laboratory, Department of Pediatrics, Radboud University Medical Center, Nijmegen, 6500 HB, The Netherlands.,Department of Human Genetics, Radboud Institute for Molecular Life Sciences and Donders Centre for Neuroscience, Radboud University Medical Center, Nijmegen, 6500 HB, The Netherlands
| | - Christopher A Powell
- Medical Research Council, Mitochondrial Biology Unit, University of Cambridge, Cambridge, CB2 OXY, United Kingdom
| | - Cristina Dallabona
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parma, 43124, Italy
| | - Alina Kurolap
- The Genetics Institute, Rambam Health Care Campus, Haifa, 3109601, Israel.,The Ruth and Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, 3109601, Israel
| | - Sara Palacios-Zambrano
- Departamento de Bioquímica, Instituto de Investigaciones Biomédicas "Alberto Sols" UAM-CSIC and Centro de Investigación Biomédica en Red en Enfermedades Raras (CIBERER). Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, 28029, Spain.,Instituto de Investigación Sanitaria Hospital 12 de Octubre (imas12), Madrid, 28041, Spain
| | - Drago Bratkovic
- SA Pathology, Women and Children's Hospital Adelaide, Adelaide, 5006, Australia
| | - Terry G J Derks
- Division of Metabolic Diseases, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, 9700 RB, The Netherlands
| | - David Bick
- HudsonAlpha Institute for Biotechnology, Huntsville, AL, 35806, USA
| | - Katelijne Bouman
- Department of Genetics, University Medical Center of Groningen, University of Groningen, Groningen, 9700 RB, The Netherlands
| | - Kathryn C Chatfield
- Department of Pediatrics, Section of Pediatric Cardiology, Children's Hospital Colorado, University of Colorado, Aurora, CO, 80045, USA
| | - Nadine Damouny-Naoum
- The Genetics Institute, Rambam Health Care Campus, Haifa, 3109601, Israel.,Department of Human Biology, Faculty of Natural Sciences, University of Haifa, Haifa, 3498838, Israel
| | - Megan K Dishop
- Department of Pathology, Children's Hospital Colorado, University of Colorado, Aurora, 80045, CO, USA
| | - Tzipora C Falik-Zaccai
- Institute of Human Genetics, Galilee Medical Center, Nahariya, 22100, Israel.,The Azrieli Faculty of Medicine in the Galilee, Bar Ilan University, Safed, 1311502, Israel
| | - Fuad Fares
- Department of Human Biology, Faculty of Natural Sciences, University of Haifa, Haifa, 3498838, Israel
| | - Ayalla Fedida
- Institute of Human Genetics, Galilee Medical Center, Nahariya, 22100, Israel.,The Azrieli Faculty of Medicine in the Galilee, Bar Ilan University, Safed, 1311502, Israel
| | - Ileana Ferrero
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parma, 43124, Italy
| | - Renata C Gallagher
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, 80045, CO, USA
| | - Rafael Garesse
- Departamento de Bioquímica, Instituto de Investigaciones Biomédicas "Alberto Sols" UAM-CSIC and Centro de Investigación Biomédica en Red en Enfermedades Raras (CIBERER). Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, 28029, Spain.,Instituto de Investigación Sanitaria Hospital 12 de Octubre (imas12), Madrid, 28041, Spain
| | - Micol Gilberti
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parma, 43124, Italy
| | - Cristina González
- Departamento de Bioquímica, Instituto de Investigaciones Biomédicas "Alberto Sols" UAM-CSIC and Centro de Investigación Biomédica en Red en Enfermedades Raras (CIBERER). Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, 28029, Spain.,Instituto de Investigación Sanitaria Hospital 12 de Octubre (imas12), Madrid, 28041, Spain
| | - Katherine Gowan
- Department of Biochemistry and Molecular Genetics, University of Colorado, Aurora, CO, 80045, USA
| | - Clair Habib
- Department of Pediatrics, Bnai Zion Medical Center, Haifa, 3339419, Israel
| | - Rebecca K Halligan
- SA Pathology, Women and Children's Hospital Adelaide, Adelaide, 5006, Australia
| | - Limor Kalfon
- Institute of Human Genetics, Galilee Medical Center, Nahariya, 22100, Israel
| | - Kaz Knight
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, 80045, CO, USA
| | - Dirk Lefeber
- Department of Human Genetics, Radboud Institute for Molecular Life Sciences and Donders Centre for Neuroscience, Radboud University Medical Center, Nijmegen, 6500 HB, The Netherlands
| | - Laura Mamblona
- Departamento de Bioquímica, Instituto de Investigaciones Biomédicas "Alberto Sols" UAM-CSIC and Centro de Investigación Biomédica en Red en Enfermedades Raras (CIBERER). Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, 28029, Spain.,Instituto de Investigación Sanitaria Hospital 12 de Octubre (imas12), Madrid, 28041, Spain
| | - Hanna Mandel
- The Ruth and Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, 3109601, Israel.,Institute of Human Genetics, Galilee Medical Center, Nahariya, 22100, Israel.,Metabolic Unit, Rambam Health Care Campus, Haifa, 3109601, Israel
| | - Adi Mory
- The Genetics Institute, Rambam Health Care Campus, Haifa, 3109601, Israel
| | - John Ottoson
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, 80045, CO, USA
| | - Tamar Paperna
- The Genetics Institute, Rambam Health Care Campus, Haifa, 3109601, Israel
| | - Ger J M Pruijn
- Department of Biomolecular Chemistry, Institute for Molecules and Materials, Radboud University, Nijmegen, 6500 HB, The Netherlands
| | - Pedro F Rebelo-Guiomar
- Medical Research Council, Mitochondrial Biology Unit, University of Cambridge, Cambridge, CB2 OXY, United Kingdom.,Graduate Program in Areas of Basic and Applied Biology (GABBA), University of Porto, Porto, 4200-135, Portugal
| | - Ann Saada
- Monique and Jacques Roboh Department of Genetic Research and the Department of Genetic and Metabolic Diseases, Hadassah-Hebrew University Medical Center, Jerusalem, 91120, Israel
| | - Bruno Sainz
- Departamento de Bioquímica, Instituto de Investigaciones Biomédicas "Alberto Sols" UAM-CSIC and Centro de Investigación Biomédica en Red en Enfermedades Raras (CIBERER). Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, 28029, Spain.,Enfermedades Crónicas y Cáncer Area, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, 28034, Spain
| | - Hayley Salvemini
- SA Pathology, Women and Children's Hospital Adelaide, Adelaide, 5006, Australia
| | - Mirthe H Schoots
- Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, 9700 RB, Groningen, The Netherlands
| | - Jan A Smeitink
- Radboud Center for Mitochondrial Medicine, Translational Metabolic Laboratory, Department of Pediatrics, Radboud University Medical Center, Nijmegen, 6500 HB, The Netherlands
| | - Maciej J Szukszto
- Medical Research Council, Mitochondrial Biology Unit, University of Cambridge, Cambridge, CB2 OXY, United Kingdom
| | - Hendrik J Ter Horst
- Division of Neonatology, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, 9700 RB, The Netherlands
| | - Frans van den Brandt
- Radboud Center for Mitochondrial Medicine, Translational Metabolic Laboratory, Department of Pediatrics, Radboud University Medical Center, Nijmegen, 6500 HB, The Netherlands
| | - Francjan J van Spronsen
- Division of Metabolic Diseases, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, 9700 RB, The Netherlands
| | - Joris A Veltman
- Department of Human Genetics, Radboud Institute for Molecular Life Sciences and Donders Centre for Neuroscience, Radboud University Medical Center, Nijmegen, 6500 HB, The Netherlands.,Institute of Genetic Medicine, Newcastle University, Newcastle, NE1 3BZ, United Kingdom
| | - Eric Wartchow
- Department of Pathology, Children's Hospital Colorado, University of Colorado, Aurora, 80045, CO, USA
| | - Liesbeth T Wintjes
- Radboud Center for Mitochondrial Medicine, Translational Metabolic Laboratory, Department of Pediatrics, Radboud University Medical Center, Nijmegen, 6500 HB, The Netherlands
| | - Yaniv Zohar
- Institute of Pathology, Rambam Health Care Campus, 3109601, Haifa, Israel
| | - Miguel A Fernández-Moreno
- Departamento de Bioquímica, Instituto de Investigaciones Biomédicas "Alberto Sols" UAM-CSIC and Centro de Investigación Biomédica en Red en Enfermedades Raras (CIBERER). Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, 28029, Spain.,Instituto de Investigación Sanitaria Hospital 12 de Octubre (imas12), Madrid, 28041, Spain
| | - Hagit N Baris
- The Genetics Institute, Rambam Health Care Campus, Haifa, 3109601, Israel.,The Ruth and Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, 3109601, Israel
| | - Claudia Donnini
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parma, 43124, Italy
| | - Michal Minczuk
- Medical Research Council, Mitochondrial Biology Unit, University of Cambridge, Cambridge, CB2 OXY, United Kingdom
| | - Richard J Rodenburg
- Radboud Center for Mitochondrial Medicine, Translational Metabolic Laboratory, Department of Pediatrics, Radboud University Medical Center, Nijmegen, 6500 HB, The Netherlands
| | - Johan L K Van Hove
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, 80045, CO, USA.
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Abstract
OBJECTIVES We describe a 13-year-old girl with a past medical history of epilepsy, intellectual impairment, dysphagia with gastric tube dependence, and autism spectrum disorder who presented with focal status epilepticus. METHODS Video-electroencephalography revealed left occipital pseudoperiodic epileptiform discharges and frequent seizures originating from the left hemisphere. The seizure was refractory to antiepileptic medications and pharmacologic coma. Subsequently, left occipital lobectomy was done. Extensive evaluation including whole exome sequencing, histopathologic examination of brain and muscle samples, mitochondrial DNA content analysis of tissue sample was completed to detect the etiology. RESULTS Skeletal muscle mitochondrial DNA content (qPCR) analysis showed approximately 37% of the mean value of age and tissue matched control group consistent with a mitochondrial depletion syndrome. Microscopic examination of the brain showed cortical abnormalities that largely consisted of infarct-like pathology in a laminar manner, abnormalities of neuronal distribution, and white matter changes. Compound heterozygous mutations of the CARS2 gene were identified by whole exome sequencing; V52G variant [p.Val52Gly (GTG>GGG):c.155 T>G in exon 1] was inherited from the mother and T188M variant[p.Thr188Met (ACG>ATG): c.563 C>T in exon 5] was inherited from the father. CONCLUSION This is the first detailed clinicopathologic description of the Alpers-Huttenlocher syndrome phenotype from CARS mutations.
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Abstract
This narrative review focuses on the pathophysiology, diagnosis, and management of status epilepticus in the context of primary mitochondrial disease. Epilepsy is common in mitochondrial disease, reported in >20% of adult cases and 40%-60% of pediatric cohorts. Status epilepticus is less frequently reported and appears to be associated with particular subgroups of mitochondrial disorders, namely defects of the mitochondrial DNA and its maintenance, and disorders of mitochondrial translation and dynamics. Mechanisms underlying mitochondrial status epilepticus are incompletely understood, and may include bioenergetic failure, oxidative stress, immune dysfunction, and impaired mitochondrial dynamics. Treatments tried in mitochondrial status epilepticus include antiepileptic drugs, anesthetic agents, magnesium, high-dose steroids, immune globulins, vagus nerve stimulation, and surgical procedures, all with variable success. The outcome of mitochondrial status epilepticus is extremely poor, and effective therapeutic options have not been reported. Improved understanding of the mechanisms underpinning mitochondrial status epilepticus is needed in order to develop more effective treatments.
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Affiliation(s)
- Shamima Rahman
- Mitochondrial Research Group, UCL Great Ormond Street Institute of Child Health, London, UK.,Metabolic Unit, Great Ormond Street Hospital for Children, NHS Foundation Trust, London, UK
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41
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Boczonadi V, Ricci G, Horvath R. Mitochondrial DNA transcription and translation: clinical syndromes. Essays Biochem 2018; 62:321-40. [PMID: 29980628 DOI: 10.1042/EBC20170103] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 05/17/2018] [Accepted: 05/21/2018] [Indexed: 01/15/2023]
Abstract
Diagnosing primary mitochondrial diseases is challenging in clinical practice. Although, defective oxidative phosphorylation (OXPHOS) is the common final pathway, it is unknown why different mtDNA or nuclear mutations result in largely heterogeneous and often tissue -specific clinical presentations. Mitochondrial tRNA (mt-tRNA) mutations are frequent causes of mitochondrial diseases both in children and adults. However numerous nuclear mutations involved in mitochondrial protein synthesis affecting ubiquitously expressed genes have been reported in association with very tissue specific clinical manifestations suggesting that there are so far unknown factors determining the tissue specificity in mitochondrial translation. Most of these gene defects result in histological abnormalities and multiple respiratory chain defects in the affected organs. The clinical phenotypes are usually early-onset, severe, and often fatal, implying the importance of mitochondrial translation from birth. However, some rare, reversible infantile mitochondrial diseases are caused by very specific defects of mitochondrial translation. An unbiased genetic approach (whole exome sequencing, RNA sequencing) combined with proteomics and functional studies revealed novel factors involved in mitochondrial translation which contribute to the clinical manifestation and recovery in these rare reversible mitochondrial conditions.
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42
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Fujii S, Sawa T, Motohashi H, Akaike T. Persulfide synthases that are functionally coupled with translation mediate sulfur respiration in mammalian cells. Br J Pharmacol 2018; 176:607-615. [PMID: 29748969 DOI: 10.1111/bph.14356] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 04/16/2018] [Accepted: 04/26/2018] [Indexed: 12/13/2022] Open
Abstract
Cysteine persulfide and polysulfide are produced in cells and exist in abundance in both low MW and protein fractions. However, the mechanism of regulation of the formation of cellular cysteine polysulfides and the physiological functions of cysteine persulfides/polysulfides produced in cells are not fully understood. We recently demonstrated that cysteinyl-tRNA synthetase (CARS) is a novel cysteine persulfide synthase. CARS is involved in protein polysulfidation that is coupled with translation. In particular, mitochondria function in biogenesis and bioenergetics is also supported and up-regulated by cysteine persulfide derived from mitochondrial CARS (also known as CARS2). Here, we provide an overview of recent advances in reactive persulfide research and our understanding of the mechanisms underlying the formation and the physiological roles of reactive persufides, with a primary focus on the formation of cysteine persulfide by CARS and the most fundamental mitochondrial bioenergetics mediated by persulfides, that is, sulfur respiration. LINKED ARTICLES: This article is part of a themed section on Chemical Biology of Reactive Sulfur Species. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.4/issuetoc.
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Affiliation(s)
- Shigemoto Fujii
- Department of Environmental Medicine and Molecular Toxicology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Tomohiro Sawa
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Hozumi Motohashi
- Department of Gene Expression Regulation, IDAC, Tohoku University, Sendai, Japan
| | - Takaaki Akaike
- Department of Environmental Medicine and Molecular Toxicology, Tohoku University Graduate School of Medicine, Sendai, Japan
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Vögtle FN, Brändl B, Larson A, Pendziwiat M, Friederich MW, White SM, Basinger A, Kücükköse C, Muhle H, Jähn JA, Keminer O, Helbig KL, Delto CF, Myketin L, Mossmann D, Burger N, Miyake N, Burnett A, van Baalen A, Lovell MA, Matsumoto N, Walsh M, Yu HC, Shinde DN, Stephani U, Van Hove JLK, Müller FJ, Helbig I. Mutations in PMPCB Encoding the Catalytic Subunit of the Mitochondrial Presequence Protease Cause Neurodegeneration in Early Childhood. Am J Hum Genet 2018; 102:557-573. [PMID: 29576218 PMCID: PMC5985287 DOI: 10.1016/j.ajhg.2018.02.014] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Accepted: 02/19/2018] [Indexed: 12/21/2022] Open
Abstract
Mitochondrial disorders causing neurodegeneration in childhood are genetically heterogeneous, and the underlying genetic etiology remains unknown in many affected individuals. We identified biallelic variants in PMPCB in individuals of four families including one family with two affected siblings with neurodegeneration and cerebellar atrophy. PMPCB encodes the catalytic subunit of the essential mitochondrial processing protease (MPP), which is required for maturation of the majority of mitochondrial precursor proteins. Mitochondria isolated from two fibroblast cell lines and induced pluripotent stem cells derived from one affected individual and differentiated neuroepithelial stem cells showed reduced PMPCB levels and accumulation of the processing intermediate of frataxin, a sensitive substrate for MPP dysfunction. Introduction of the identified PMPCB variants into the homologous S. cerevisiae Mas1 protein resulted in a severe growth and MPP processing defect leading to the accumulation of mitochondrial precursor proteins and early impairment of the biogenesis of iron-sulfur clusters, which are indispensable for a broad range of crucial cellular functions. Analysis of biopsy materials of an affected individual revealed changes and decreased activity in iron-sulfur cluster-containing respiratory chain complexes and dysfunction of mitochondrial and cytosolic Fe-S cluster-dependent enzymes. We conclude that biallelic mutations in PMPCB cause defects in MPP proteolytic activity leading to dysregulation of iron-sulfur cluster biogenesis and triggering a complex neurological phenotype of neurodegeneration in early childhood.
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Affiliation(s)
- F-Nora Vögtle
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg 79104, Germany.
| | - Björn Brändl
- Department of Psychiatry and Psychotherapy, University Hospital Schleswig Holstein, Kiel 24105, Germany
| | - Austin Larson
- Department of Pediatrics, Section of Clinical Genetics and Metabolism, University of Colorado, Aurora, CO 80045, USA
| | - Manuela Pendziwiat
- Department of Neuropediatrics, Christian-Albrechts-University of Kiel, Kiel 24105, Germany
| | - Marisa W Friederich
- Department of Pediatrics, Section of Clinical Genetics and Metabolism, University of Colorado, Aurora, CO 80045, USA
| | - Susan M White
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, VIC 3052, Australia; Department of Paediatrics, University of Melbourne, Melbourne, VIC 3052, Australia
| | - Alice Basinger
- Cook Children's Physician Network, Department of Genetics, Fort Worth, TX 76102, USA
| | - Cansu Kücükköse
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg 79104, Germany; Faculty of Biology, University of Freiburg, Freiburg 79104, Germany
| | - Hiltrud Muhle
- Department of Neuropediatrics, Christian-Albrechts-University of Kiel, Kiel 24105, Germany
| | - Johanna A Jähn
- Department of Neuropediatrics, Christian-Albrechts-University of Kiel, Kiel 24105, Germany
| | - Oliver Keminer
- Fraunhofer-Institut für Molekularbiologie und Angewandte Ökologie IME, ScreeningPort, Hamburg 22525, Germany
| | - Katherine L Helbig
- Division of Neurology, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Carolyn F Delto
- Rudolf Virchow Center for Experimental Biomedicine, University of Würzburg, Würzburg 97080, Germany
| | - Lisa Myketin
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg 79104, Germany
| | - Dirk Mossmann
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg 79104, Germany
| | - Nils Burger
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg 79104, Germany
| | - Noriko Miyake
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Audrey Burnett
- Cook Children's Physician Network, Department of Genetics, Fort Worth, TX 76102, USA
| | - Andreas van Baalen
- Department of Neuropediatrics, Christian-Albrechts-University of Kiel, Kiel 24105, Germany
| | - Mark A Lovell
- Department of Pathology, University of Colorado, Aurora, CO 80045, USA
| | - Naomichi Matsumoto
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Maie Walsh
- Adult Genetic Medicine, Royal Melbourne Hospital, Melbourne, VIC 3052, Australia
| | - Hung-Chun Yu
- Department of Pediatrics, Section of Clinical Genetics and Metabolism, University of Colorado, Aurora, CO 80045, USA
| | - Deepali N Shinde
- Division of Clinical Genomics, Ambry Genetics, Aliso Viejo, CA 92656, USA
| | - Ulrich Stephani
- Department of Neuropediatrics, Christian-Albrechts-University of Kiel, Kiel 24105, Germany
| | - Johan L K Van Hove
- Department of Pediatrics, Section of Clinical Genetics and Metabolism, University of Colorado, Aurora, CO 80045, USA
| | - Franz-Josef Müller
- Department of Psychiatry and Psychotherapy, University Hospital Schleswig Holstein, Kiel 24105, Germany; Max Planck Institute for Molecular Genetics, Berlin 14195, Germany
| | - Ingo Helbig
- Department of Neuropediatrics, Christian-Albrechts-University of Kiel, Kiel 24105, Germany; Division of Neurology, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
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Kamps R, Szklarczyk R, Theunissen TE, Hellebrekers DMEI, Sallevelt SCEH, Boesten IB, de Koning B, van den Bosch BJ, Salomons GS, Simas-Mendes M, Verdijk R, Schoonderwoerd K, de Coo IFM, Vanoevelen JM, Smeets HJM. Genetic defects in mtDNA-encoded protein translation cause pediatric, mitochondrial cardiomyopathy with early-onset brain disease. Eur J Hum Genet 2018; 26:537-551. [PMID: 29440775 PMCID: PMC5891491 DOI: 10.1038/s41431-017-0058-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 11/17/2017] [Accepted: 11/23/2017] [Indexed: 01/10/2023] Open
Abstract
This study aims to identify gene defects in pediatric cardiomyopathy and early-onset brain disease with oxidative phosphorylation (OXPHOS) deficiencies. We applied whole-exome sequencing in three patients with pediatric cardiomyopathy and early-onset brain disease with OXPHOS deficiencies. The brain pathology was studied by MRI analysis. In consanguineous patient 1, we identified a homozygous intronic variant (c.850-3A > G) in the QRSL1 gene, which was predicted to cause abnormal splicing. The variant segregated with the disease and affected the protein function, which was confirmed by complementation studies, restoring OXPHOS function only with wild-type QRSL1. Patient 2 was compound heterozygous for two novel affected and disease-causing variants (c.[253G > A];[938G > A]) in the MTO1 gene. In patient 3, we detected one unknown affected and disease-causing variants (c.2872C > T) and one known disease-causing variant (c.1774C > T) in the AARS2 gene. The c.1774C > T variant was present in the paternal copy of the AARS2 gene, the c.2872C > T in the maternal copy. All genes were involved in translation of mtDNA-encoded proteins. Defects in mtDNA-encoded protein translation lead to severe pediatric cardiomyopathy and brain disease with OXPHOS abnormalities. This suggests that the heart and brain are particularly sensitive to defects in mitochondrial protein synthesis during late embryonic or early postnatal development, probably due to the massive mitochondrial biogenesis occurring at that stage. If both the heart and brain are involved, the prognosis is poor with a likely fatal outcome at young age.
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Affiliation(s)
- Rick Kamps
- Department of Genetics and Cell Biology, Maastricht University, Maastricht, The Netherlands
- School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands
| | - Radek Szklarczyk
- Department of Genetics and Cell Biology, Maastricht University, Maastricht, The Netherlands
| | - Tom E Theunissen
- Department of Genetics and Cell Biology, Maastricht University, Maastricht, The Netherlands
| | | | | | - Iris B Boesten
- Department of Clinical Genetics, MUMC, Maastricht, The Netherlands
| | - Bart de Koning
- Department of Clinical Genetics, MUMC, Maastricht, The Netherlands
| | | | - Gajja S Salomons
- Department of Clinical Chemistry, VU University Medical Center/Neuroscience Campus Amsterdam, Amsterdam, The Netherlands
| | - Marisa Simas-Mendes
- Department of Clinical Chemistry, VU University Medical Center/Neuroscience Campus Amsterdam, Amsterdam, The Netherlands
| | - Rob Verdijk
- Department of Pathology, Erasmus Medical Centre, Rotterdam, The Netherlands
| | - Kees Schoonderwoerd
- Department of Clinical Genetics, Erasmus Medical Centre, Rotterdam, The Netherlands
| | | | - Jo M Vanoevelen
- Department of Genetics and Cell Biology, Maastricht University, Maastricht, The Netherlands
- Department of Clinical Genetics, MUMC, Maastricht, The Netherlands
| | - Hubert J M Smeets
- Department of Genetics and Cell Biology, Maastricht University, Maastricht, The Netherlands.
- School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands.
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Bruni F, Di Meo I, Bellacchio E, Webb BD, McFarland R, Chrzanowska‐Lightowlers ZM, He L, Skorupa E, Moroni I, Ardissone A, Walczak A, Tyynismaa H, Isohanni P, Mandel H, Prokisch H, Haack T, Bonnen PE, Enrico B, Pronicka E, Ghezzi D, Taylor RW, Diodato D. Clinical, biochemical, and genetic features associated with VARS2-related mitochondrial disease. Hum Mutat 2018; 39:563-578. [PMID: 29314548 PMCID: PMC5873438 DOI: 10.1002/humu.23398] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 12/21/2017] [Accepted: 12/28/2017] [Indexed: 01/17/2023]
Abstract
In recent years, an increasing number of mitochondrial disorders have been associated with mutations in mitochondrial aminoacyl‐tRNA synthetases (mt‐aaRSs), which are key enzymes of mitochondrial protein synthesis. Bi‐allelic functional variants in VARS2, encoding the mitochondrial valyl tRNA‐synthetase, were first reported in a patient with psychomotor delay and epilepsia partialis continua associated with an oxidative phosphorylation (OXPHOS) Complex I defect, before being described in a patient with a neonatal form of encephalocardiomyopathy. Here we provide a detailed genetic, clinical, and biochemical description of 13 patients, from nine unrelated families, harboring VARS2 mutations. All patients except one, who manifested with a less severe disease course, presented at birth exhibiting severe encephalomyopathy and cardiomyopathy. Features included hypotonia, psychomotor delay, seizures, feeding difficulty, abnormal cranial MRI, and elevated lactate. The biochemical phenotype comprised a combined Complex I and Complex IV OXPHOS defect in muscle, with patient fibroblasts displaying normal OXPHOS activity. Homology modeling supported the pathogenicity of VARS2 missense variants. The detailed description of this cohort further delineates our understanding of the clinical presentation associated with pathogenic VARS2 variants and we recommend that this gene should be considered in early‐onset mitochondrial encephalomyopathies or encephalocardiomyopathies.
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Affiliation(s)
- Francesco Bruni
- Wellcome Centre for Mitochondrial ResearchInstitute of NeuroscienceNewcastle UniversityNewcastle upon TyneUnited Kingdom
| | - Ivano Di Meo
- Molecular Neurogenetics UnitFoundation IRCCS Neurological Institute C. BestaMilanItaly
| | - Emanuele Bellacchio
- Genetics and Rare DiseasesResearch Division‘Bambino Gesù’ Children HospitalRomeItaly
| | - Bryn D. Webb
- Department of Genetics and Genomic SciencesIcahn School of Medicine at Mount SinaiNew YorkNew York
| | - Robert McFarland
- Wellcome Centre for Mitochondrial ResearchInstitute of NeuroscienceNewcastle UniversityNewcastle upon TyneUnited Kingdom
| | | | - Langping He
- Wellcome Centre for Mitochondrial ResearchInstitute of NeuroscienceNewcastle UniversityNewcastle upon TyneUnited Kingdom
| | - Ewa Skorupa
- Department of BiochemistryRadioimmunology and Experimental MedicineThe Children's Memorial Health InstituteWarsawPoland
| | - Isabella Moroni
- Child Neurology UnitFoundation IRCCS Neurological Institute “C. Besta”MilanItaly
| | - Anna Ardissone
- Molecular Neurogenetics UnitFoundation IRCCS Neurological Institute C. BestaMilanItaly
- Child Neurology UnitFoundation IRCCS Neurological Institute “C. Besta”MilanItaly
- Department of Molecular and Translational Medicine DIMETUniversity of Milan‐BicoccaMilanItaly
| | - Anna Walczak
- Department of Medical GeneticsCentre of BiostructureMedical University of WarsawWarsawPoland
| | - Henna Tyynismaa
- Research Programs UnitMolecular NeurologyUniversity of HelsinkiHelsinkiFinland
| | - Pirjo Isohanni
- Research Programs UnitMolecular NeurologyUniversity of HelsinkiHelsinkiFinland
- Department of Pediatric NeurologyChildren's HospitalUniversity of Helsinki and Helsinki University HospitalHelsinkiFinland
| | - Hanna Mandel
- Institute of Human Genetics and Metabolic DiseasesGalilee Medical CenterNahariyaIsrael
| | - Holger Prokisch
- Institute of Human GeneticsTechnische Universität MünchenMunichGermany
- Institute of Human GeneticsHelmholtz Zentrum MünchenNeuherbergGermany
| | - Tobias Haack
- Institute of Human GeneticsHelmholtz Zentrum MünchenNeuherbergGermany
| | - Penelope E. Bonnen
- Department of Molecular and Human GeneticsBaylor College of MedicineHoustonTexas
| | - Bertini Enrico
- Unit of Neuromuscular and Neurodegenerative DisordersLaboratory of Molecular Medicine‘Bambino Ges.’ Children's Research HospitalRomeItaly
| | - Ewa Pronicka
- Department of PediatricsNutrition and Metabolic DiseasesThe Children's Memorial Health InstituteWarsawPoland
| | - Daniele Ghezzi
- Molecular Neurogenetics UnitFoundation IRCCS Neurological Institute C. BestaMilanItaly
- Department of Pathophysiology and TransplantationUniversity of MilanMilanItaly
| | - Robert W. Taylor
- Wellcome Centre for Mitochondrial ResearchInstitute of NeuroscienceNewcastle UniversityNewcastle upon TyneUnited Kingdom
| | - Daria Diodato
- Unit of Neuromuscular and Neurodegenerative DisordersLaboratory of Molecular Medicine‘Bambino Ges.’ Children's Research HospitalRomeItaly
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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: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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).
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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
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Sawa T, Ono K, Tsutsuki H, Zhang T, Ida T, Nishida M, Akaike T. Reactive Cysteine Persulphides: Occurrence, Biosynthesis, Antioxidant Activity, Methodologies, and Bacterial Persulphide Signalling. Adv Microb Physiol 2018; 72:1-28. [PMID: 29778212 DOI: 10.1016/bs.ampbs.2018.01.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Cysteine hydropersulphide (CysSSH) is a cysteine derivative having one additional sulphur atom bound to a cysteinyl thiol group. Recent advances in the development of analytical methods for detection and quantification of persulphides and polysulphides have revealed the biological presence, in both prokaryotes and eukaryotes, of hydropersulphides in diverse forms such as CysSSH, homocysteine hydropersulphide, glutathione hydropersulphide, bacillithiol hydropersulphide, coenzyme A hydropersulphide, and protein hydropersulphides. Owing to the chemical reactivity of the persulphide moiety, biological systems utilize persulphides as important intermediates in the synthesis of various sulphur-containing biomolecules. Accumulating evidence has revealed another important feature of persulphides: their potent reducing activity, which implies that they are implicated in the regulation of redox signalling and antioxidant functions. In this chapter, we discuss the biological occurrence and possible biosynthetic mechanisms of CysSSH and related persulphides, and we include descriptions of recent advances in the analytical methods that have been used to detect and quantitate persulphide species. We also discuss the antioxidant activity of persulphide species that contributes to protecting cells from reactive oxygen species-associated damage, and we examine the signalling roles of CysSSH in bacteria.
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Akaike T, Ida T, Wei FY, Nishida M, Kumagai Y, Alam MM, Ihara H, Sawa T, Matsunaga T, Kasamatsu S, Nishimura A, Morita M, Tomizawa K, Nishimura A, Watanabe S, Inaba K, Shima H, Tanuma N, Jung M, Fujii S, Watanabe Y, Ohmuraya M, Nagy P, Feelisch M, Fukuto JM, Motohashi H. Cysteinyl-tRNA synthetase governs cysteine polysulfidation and mitochondrial bioenergetics. Nat Commun 2017; 8:1177. [PMID: 29079736 DOI: 10.1038/s41467-017-01311-y] [Citation(s) in RCA: 323] [Impact Index Per Article: 46.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 08/29/2017] [Indexed: 12/30/2022] Open
Abstract
Cysteine hydropersulfide (CysSSH) occurs in abundant quantities in various organisms, yet little is known about its biosynthesis and physiological functions. Extensive persulfide formation is apparent in cysteine-containing proteins in Escherichia coli and mammalian cells and is believed to result from post-translational processes involving hydrogen sulfide-related chemistry. Here we demonstrate effective CysSSH synthesis from the substrate l-cysteine, a reaction catalyzed by prokaryotic and mammalian cysteinyl-tRNA synthetases (CARSs). Targeted disruption of the genes encoding mitochondrial CARSs in mice and human cells shows that CARSs have a crucial role in endogenous CysSSH production and suggests that these enzymes serve as the principal cysteine persulfide synthases in vivo. CARSs also catalyze co-translational cysteine polysulfidation and are involved in the regulation of mitochondrial biogenesis and bioenergetics. Investigating CARS-dependent persulfide production may thus clarify aberrant redox signaling in physiological and pathophysiological conditions, and suggest therapeutic targets based on oxidative stress and mitochondrial dysfunction. Cysteine hydropersulfides (CysSSH) are believed to have a cellular redox protective role. Here the authors show that these species can be produced from L-cysteine by cysteinyl-tRNA synthetases and that these enzymes are also involved in mitochondrial biogenesis and bioenergetics regulation.
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Meyer-Schuman R, Antonellis A. Emerging mechanisms of aminoacyl-tRNA synthetase mutations in recessive and dominant human disease. Hum Mol Genet 2017; 26:R114-R127. [PMID: 28633377 PMCID: PMC5886470 DOI: 10.1093/hmg/ddx231] [Citation(s) in RCA: 112] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 06/09/2017] [Accepted: 06/12/2017] [Indexed: 12/29/2022] Open
Abstract
Aminoacyl-tRNA synthetases (ARSs) are responsible for charging amino acids to cognate tRNA molecules, which is the essential first step of protein translation. Interestingly, mutations in genes encoding ARS enzymes have been implicated in a broad spectrum of human inherited diseases. Bi-allelic mutations in ARSs typically cause severe, early-onset, recessive diseases that affect a wide range of tissues. The vast majority of these mutations show loss-of-function effects and impair protein translation. However, it is not clear how a subset cause tissue-specific phenotypes. In contrast, dominant ARS-mediated diseases specifically affect the peripheral nervous system-most commonly causing axonal peripheral neuropathy-and usually manifest later in life. These neuropathies are linked to heterozygosity for missense mutations in five ARS genes, which points to a shared mechanism of disease. However, it is not clear if a loss-of-function mechanism or a toxic gain-of-function mechanism is responsible for ARS-mediated neuropathy, or if a combination of these mechanisms operate on a mutation-specific basis. Here, we review our current understanding of recessive and dominant ARS-mediated disease. We also propose future directions for defining the molecular mechanisms of ARS mutations toward designing therapies for affected patient populations.
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Affiliation(s)
- Rebecca Meyer-Schuman
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Anthony Antonellis
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48109, USA
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Abstract
ABSTRACTThis review aims at summarizing and discussing previous and recent findings concerning the cerebral manifestations of mitochondrial disorders (MIDs). MIDs frequently present as mitochondrial multiorgan disorder syndrome (MIMODS) either already at onset or later in the course. After the muscle, the brain is the organ second most frequently affected in MIMODS. Cerebral manifestations of MIDs are variable and may present with or without a lesion on imaging or functional studies, but there can be imaging/functional lesions without clinical manifestations. The most well-known cerebral manifestations of MIDs include stroke-like episodes, epilepsy, headache, ataxia, movement disorders, hypopituitarism, muscle weakness, psychiatric abnormalities, nystagmus, white and gray matter lesions, atrophy, basal ganglia calcification, and hypometabolism on 2-deoxy-2-[fluorine-18]fluoro-D-glucose positron-emission tomography. For most MIDs, only symptomatic therapy is currently available. Symptomatic treatment should be supplemented by vitamins, cofactors, and antioxidants. In conclusion, cerebral manifestations of MIDs need to be recognized and appropriately managed because they strongly determine the outcome of MID patients.
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