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Antolínez-Fernández Á, Esteban-Ramos P, Fernández-Moreno MÁ, Clemente P. Molecular pathways in mitochondrial disorders due to a defective mitochondrial protein synthesis. Front Cell Dev Biol 2024; 12:1410245. [PMID: 38855161 PMCID: PMC11157125 DOI: 10.3389/fcell.2024.1410245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Accepted: 05/09/2024] [Indexed: 06/11/2024] Open
Abstract
Mitochondria play a central role in cellular metabolism producing the necessary ATP through oxidative phosphorylation. As a remnant of their prokaryotic past, mitochondria contain their own genome, which encodes 13 subunits of the oxidative phosphorylation system, as well as the tRNAs and rRNAs necessary for their translation in the organelle. Mitochondrial protein synthesis depends on the import of a vast array of nuclear-encoded proteins including the mitochondrial ribosome protein components, translation factors, aminoacyl-tRNA synthetases or assembly factors among others. Cryo-EM studies have improved our understanding of the composition of the mitochondrial ribosome and the factors required for mitochondrial protein synthesis and the advances in next-generation sequencing techniques have allowed for the identification of a growing number of genes involved in mitochondrial pathologies with a defective translation. These disorders are often multisystemic, affecting those tissues with a higher energy demand, and often present with neurodegenerative phenotypes. In this article, we review the known proteins required for mitochondrial translation, the disorders that derive from a defective mitochondrial protein synthesis and the animal models that have been established for their study.
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Affiliation(s)
- Álvaro Antolínez-Fernández
- Instituto de Investigaciones Biomédicas Sols-Morreale (IIBM), Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, Madrid, Spain
- Departamento de Bioquímica, Universidad Autónoma de Madrid, Madrid, Spain
| | - Paula Esteban-Ramos
- Instituto de Investigaciones Biomédicas Sols-Morreale (IIBM), Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, Madrid, Spain
- Departamento de Bioquímica, Universidad Autónoma de Madrid, Madrid, Spain
| | - Miguel Ángel Fernández-Moreno
- Instituto de Investigaciones Biomédicas Sols-Morreale (IIBM), Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, Madrid, Spain
- Departamento de Bioquímica, Universidad Autónoma de Madrid, Madrid, Spain
| | - Paula Clemente
- Instituto de Investigaciones Biomédicas Sols-Morreale (IIBM), Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, Madrid, Spain
- Departamento de Bioquímica, Universidad Autónoma de Madrid, Madrid, Spain
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Li B, Liu F, Chen X, Chen T, Zhang J, Liu Y, Yao Y, Hu W, Zhang M, Wang B, Liu L, Chen K, Wu Y. FARS2 Deficiency Causes Cardiomyopathy by Disrupting Mitochondrial Homeostasis and the Mitochondrial Quality Control System. Circulation 2024; 149:1268-1284. [PMID: 38362779 PMCID: PMC11017836 DOI: 10.1161/circulationaha.123.064489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 12/13/2023] [Indexed: 02/17/2024]
Abstract
BACKGROUND Hypertrophic cardiomyopathy (HCM) is a common heritable heart disease. Although HCM has been reported to be associated with many variants of genes involved in sarcomeric protein biomechanics, pathogenic genes have not been identified in patients with partial HCM. FARS2 (the mitochondrial phenylalanyl-tRNA synthetase), a type of mitochondrial aminoacyl-tRNA synthetase, plays a role in the mitochondrial translation machinery. Several variants of FARS2 have been suggested to cause neurological disorders; however, FARS2-associated diseases involving other organs have not been reported. We identified FARS2 as a potential novel pathogenic gene in cardiomyopathy and investigated its effects on mitochondrial homeostasis and the cardiomyopathy phenotype. METHODS FARS2 variants in patients with HCM were identified using whole-exome sequencing, Sanger sequencing, molecular docking analyses, and cell model investigation. Fars2 conditional mutant (p.R415L) or knockout mice, fars2-knockdown zebrafish, and Fars2-knockdown neonatal rat ventricular myocytes were engineered to construct FARS2 deficiency models both in vivo and in vitro. The effects of FARS2 and its role in mitochondrial homeostasis were subsequently evaluated using RNA sequencing and mitochondrial functional analyses. Myocardial tissues from patients were used for further verification. RESULTS We identified 7 unreported FARS2 variants in patients with HCM. Heart-specific Fars2-deficient mice presented cardiac hypertrophy, left ventricular dilation, progressive heart failure accompanied by myocardial and mitochondrial dysfunction, and a short life span. Heterozygous cardiac-specific Fars2R415L mice displayed a tendency to cardiac hypertrophy at age 4 weeks, accompanied by myocardial dysfunction. In addition, fars2-knockdown zebrafish presented pericardial edema and heart failure. FARS2 deficiency impaired mitochondrial homeostasis by directly blocking the aminoacylation of mt-tRNAPhe and inhibiting the synthesis of mitochondrial proteins, ultimately contributing to an imbalanced mitochondrial quality control system by accelerating mitochondrial hyperfragmentation and disrupting mitochondrion-related autophagy. Interfering with the mitochondrial quality control system using adeno-associated virus 9 or specific inhibitors mitigated the cardiac and mitochondrial dysfunction triggered by FARS2 deficiency by restoring mitochondrial homeostasis. CONCLUSIONS Our findings unveil the previously unrecognized role of FARS2 in heart and mitochondrial homeostasis. This study may provide new insights into the molecular diagnosis and prevention of heritable cardiomyopathy as well as therapeutic options for FARS2-associated cardiomyopathy.
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Affiliation(s)
- Bowen Li
- Department of Biochemistry and Molecular Biology, Shaanxi Provincial Key Laboratory of Clinical Genetics (B.L., X.C., T.C., J.Z., Y.L., Y.Y., W.H., M.Z., Y.W.), Air Force Medical University, Xi’an, China
| | - Fangfang Liu
- Department of Neurobiology (F.L.), Air Force Medical University, Xi’an, China
| | - Xihui Chen
- Department of Biochemistry and Molecular Biology, Shaanxi Provincial Key Laboratory of Clinical Genetics (B.L., X.C., T.C., J.Z., Y.L., Y.Y., W.H., M.Z., Y.W.), Air Force Medical University, Xi’an, China
| | - Tangdong Chen
- Department of Biochemistry and Molecular Biology, Shaanxi Provincial Key Laboratory of Clinical Genetics (B.L., X.C., T.C., J.Z., Y.L., Y.Y., W.H., M.Z., Y.W.), Air Force Medical University, Xi’an, China
| | - Juan Zhang
- Department of Biochemistry and Molecular Biology, Shaanxi Provincial Key Laboratory of Clinical Genetics (B.L., X.C., T.C., J.Z., Y.L., Y.Y., W.H., M.Z., Y.W.), Air Force Medical University, Xi’an, China
| | - Yifeng Liu
- Department of Biochemistry and Molecular Biology, Shaanxi Provincial Key Laboratory of Clinical Genetics (B.L., X.C., T.C., J.Z., Y.L., Y.Y., W.H., M.Z., Y.W.), Air Force Medical University, Xi’an, China
| | - Yan Yao
- Department of Biochemistry and Molecular Biology, Shaanxi Provincial Key Laboratory of Clinical Genetics (B.L., X.C., T.C., J.Z., Y.L., Y.Y., W.H., M.Z., Y.W.), Air Force Medical University, Xi’an, China
| | - Weihong Hu
- Department of Biochemistry and Molecular Biology, Shaanxi Provincial Key Laboratory of Clinical Genetics (B.L., X.C., T.C., J.Z., Y.L., Y.Y., W.H., M.Z., Y.W.), Air Force Medical University, Xi’an, China
| | - Mengjie Zhang
- Department of Biochemistry and Molecular Biology, Shaanxi Provincial Key Laboratory of Clinical Genetics (B.L., X.C., T.C., J.Z., Y.L., Y.Y., W.H., M.Z., Y.W.), Air Force Medical University, Xi’an, China
| | - Bo Wang
- School of Basic Medicine, Department of Ultrasound, Xijing Hypertrophic Cardiomyopathy Center, Xijing Hospital (B.W., L.L.), Air Force Medical University, Xi’an, China
| | - Liwen Liu
- School of Basic Medicine, Department of Ultrasound, Xijing Hypertrophic Cardiomyopathy Center, Xijing Hospital (B.W., L.L.), Air Force Medical University, Xi’an, China
| | - Kun Chen
- Department of Anatomy, Histology and Embryology and K.K. Leung Brain Research Center (K.C.), Air Force Medical University, Xi’an, China
| | - Yuanming Wu
- Department of Biochemistry and Molecular Biology, Shaanxi Provincial Key Laboratory of Clinical Genetics (B.L., X.C., T.C., J.Z., Y.L., Y.Y., W.H., M.Z., Y.W.), Air Force Medical University, Xi’an, China
- Department of Clinical Laboratory, Tangdu Hospital (Y.W.), Air Force Medical University, Xi’an, China
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He Y, Zhu G, Li X, Zhou M, Guan MX. Deficient tRNA posttranscription modification dysregulated the mitochondrial quality controls and apoptosis. iScience 2024; 27:108883. [PMID: 38318358 PMCID: PMC10838789 DOI: 10.1016/j.isci.2024.108883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 10/26/2023] [Accepted: 01/08/2024] [Indexed: 02/07/2024] Open
Abstract
Mitochondria are dynamic organelles in cellular metabolism and physiology. Mitochondrial DNA (mtDNA) mutations are associated with a broad spectrum of clinical abnormalities. However, mechanisms underlying mtDNA mutations regulate intracellular signaling related to the mitochondrial and cellular integrity are less explored. Here, we demonstrated that mt-tRNAMet 4435A>G mutation-induced nucleotide modification deficiency dysregulated the expression of nuclear genes involved in cytosolic proteins involved in oxidative phosphorylation system (OXPHOS) and impaired the assemble and integrity of OXPHOS complexes. These dysfunctions caused mitochondrial dynamic imbalance, thereby increasing fission and decreasing fusion. Excessive fission impaired the process of autophagy including initiation phase, formation, and maturation of autophagosome. Strikingly, the m.4435A>G mutation upregulated the PARKIN dependent mitophagy pathways but downregulated the ubiquitination-independent mitophagy. These alterations promoted intrinsic apoptotic process for the removal of damaged cells. Our findings provide new insights into mechanism underlying deficient tRNA posttranscription modification regulated intracellular signaling related to the mitochondrial and cellular integrity.
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Affiliation(s)
- Yunfan He
- Center for Mitochondrial Biomedicine, the Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, Zhejiang, China
- Institute of Genetics, Zhejiang University International School of Medicine, Hangzhou, Zhejiang, China
- Center for Genetic Medicine, Zhejiang University International Institute of Medicine, Yiwu, Zhejiang, China
| | - Gao Zhu
- Center for Mitochondrial Biomedicine, the Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, Zhejiang, China
- Institute of Genetics, Zhejiang University International School of Medicine, Hangzhou, Zhejiang, China
- Center for Genetic Medicine, Zhejiang University International Institute of Medicine, Yiwu, Zhejiang, China
- Zhejiang Provincial Key Laboratory of Genetic & Developmental Disorders, Hangzhou, Zhejiang, China
| | - Xincheng Li
- Institute of Genetics, Zhejiang University International School of Medicine, Hangzhou, Zhejiang, China
| | - Mi Zhou
- Institute of Genetics, Zhejiang University International School of Medicine, Hangzhou, Zhejiang, China
| | - Min-Xin Guan
- Center for Mitochondrial Biomedicine, the Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, Zhejiang, China
- Institute of Genetics, Zhejiang University International School of Medicine, Hangzhou, Zhejiang, China
- Center for Genetic Medicine, Zhejiang University International Institute of Medicine, Yiwu, Zhejiang, China
- Zhejiang Provincial Key Laboratory of Genetic & Developmental Disorders, Hangzhou, Zhejiang, China
- Key Lab of Reproductive Genetics, Ministry of Education of PRC, Zhejiang University, Hangzhou, Zhejiang, China
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Wang Y, Wang G, Hu S, Yin C, Zhao P, Zhou X, Shao S, Liu R, Hu W, Liu GL, Ke W, Song Z. FARSB Facilitates Hepatocellular Carcinoma Progression by Activating the mTORC1 Signaling Pathway. Int J Mol Sci 2023; 24:16709. [PMID: 38069034 PMCID: PMC10706030 DOI: 10.3390/ijms242316709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 11/20/2023] [Accepted: 11/20/2023] [Indexed: 12/18/2023] Open
Abstract
Hepatocellular carcinoma (HCC) is a common malignant tumor with high mortality. Human phenylalanine tRNA synthetase (PheRS) comprises two α catalytic subunits encoded by the FARSA gene and two β regulatory subunits encoded by the FARSB gene. FARSB is a potential oncogene, but no experimental data show the relationship between FARSB and HCC progression. We found that the high expression of FARSB in liver cancer is closely related to patients' low survival and poor prognosis. In liver cancer cells, the mRNA and protein expression levels of FARSB are increased and promote cell proliferation and migration. Mechanistically, FARSB activates the mTOR complex 1 (mTORC1) signaling pathway by binding to the component Raptor of the mTORC1 complex to play a role in promoting cancer. In addition, we found that FARSB can inhibit erastin-induced ferroptosis by regulating the mTOR signaling pathway, which may be another mechanism by which FARSB promotes HCC progression. In summary, FARSB promotes HCC progression and is associated with the poor prognosis of patients. FARSB is expected to be a biomarker for early screening and treatment of HCC.
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Affiliation(s)
- Yaofeng Wang
- Department of Hepatobiliary Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China; (Y.W.); (G.W.); (S.H.); (C.Y.); (P.Z.); (X.Z.); (S.S.); (R.L.)
| | - Gengqiao Wang
- Department of Hepatobiliary Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China; (Y.W.); (G.W.); (S.H.); (C.Y.); (P.Z.); (X.Z.); (S.S.); (R.L.)
| | - Shaobo Hu
- Department of Hepatobiliary Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China; (Y.W.); (G.W.); (S.H.); (C.Y.); (P.Z.); (X.Z.); (S.S.); (R.L.)
| | - Chuanzheng Yin
- Department of Hepatobiliary Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China; (Y.W.); (G.W.); (S.H.); (C.Y.); (P.Z.); (X.Z.); (S.S.); (R.L.)
| | - Peng Zhao
- Department of Hepatobiliary Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China; (Y.W.); (G.W.); (S.H.); (C.Y.); (P.Z.); (X.Z.); (S.S.); (R.L.)
| | - Xing Zhou
- Department of Hepatobiliary Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China; (Y.W.); (G.W.); (S.H.); (C.Y.); (P.Z.); (X.Z.); (S.S.); (R.L.)
| | - Shuyu Shao
- Department of Hepatobiliary Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China; (Y.W.); (G.W.); (S.H.); (C.Y.); (P.Z.); (X.Z.); (S.S.); (R.L.)
| | - Ran Liu
- Department of Hepatobiliary Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China; (Y.W.); (G.W.); (S.H.); (C.Y.); (P.Z.); (X.Z.); (S.S.); (R.L.)
| | - Wenjun Hu
- School of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China; (W.H.); (G.L.L.)
| | - Gang Logan Liu
- School of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China; (W.H.); (G.L.L.)
| | - Wenbo Ke
- Department of Hepatobiliary Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China; (Y.W.); (G.W.); (S.H.); (C.Y.); (P.Z.); (X.Z.); (S.S.); (R.L.)
| | - Zifang Song
- Department of Hepatobiliary Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China; (Y.W.); (G.W.); (S.H.); (C.Y.); (P.Z.); (X.Z.); (S.S.); (R.L.)
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Tyynismaa H. Disease models of mitochondrial aminoacyl-tRNA synthetase defects. J Inherit Metab Dis 2023; 46:817-823. [PMID: 37410890 DOI: 10.1002/jimd.12652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 06/12/2023] [Accepted: 06/30/2023] [Indexed: 07/08/2023]
Abstract
Mitochondrial aminoacyl-tRNA synthetases (mtARS) are enzymes critical for the first step of mitochondrial protein synthesis by charging mitochondrial tRNAs with their cognate amino acids. Pathogenic variants in all 19 nuclear mtARS genes are now recognized as causing recessive mitochondrial diseases. Most mtARS disorders affect the nervous system, but the phenotypes range from multisystem diseases to tissue-specific manifestations. However, the mechanisms behind the tissue specificities are poorly understood, and challenges remain in obtaining accurate disease models for developing and testing treatments. Here, some of the currently existing disease models that have increased our understanding of mtARS defects are discussed.
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Affiliation(s)
- Henna Tyynismaa
- Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
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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] [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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7
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Kalotay E, Klugmann M, Housley GD, Fröhlich D. Recessive aminoacyl-tRNA synthetase disorders: lessons learned from in vivo disease models. Front Neurosci 2023; 17:1182874. [PMID: 37274208 PMCID: PMC10234152 DOI: 10.3389/fnins.2023.1182874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 04/17/2023] [Indexed: 06/06/2023] Open
Abstract
Protein synthesis is a fundamental process that underpins almost every aspect of cellular functioning. Intriguingly, despite their common function, recessive mutations in aminoacyl-tRNA synthetases (ARSs), the family of enzymes that pair tRNA molecules with amino acids prior to translation on the ribosome, cause a diverse range of multi-system disorders that affect specific groups of tissues. Neurological development is impaired in most ARS-associated disorders. In addition to central nervous system defects, diseases caused by recessive mutations in cytosolic ARSs commonly affect the liver and lungs. Patients with biallelic mutations in mitochondrial ARSs often present with encephalopathies, with variable involvement of peripheral systems. Many of these disorders cause severe disability, and as understanding of their pathogenesis is currently limited, there are no effective treatments available. To address this, accurate in vivo models for most of the recessive ARS diseases are urgently needed. Here, we discuss approaches that have been taken to model recessive ARS diseases in vivo, highlighting some of the challenges that have arisen in this process, as well as key results obtained from these models. Further development and refinement of animal models is essential to facilitate a better understanding of the pathophysiology underlying recessive ARS diseases, and ultimately to enable development and testing of effective therapies.
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Affiliation(s)
- Elizabeth Kalotay
- Translational Neuroscience Facility and Department of Physiology, School of Biomedical Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Matthias Klugmann
- Translational Neuroscience Facility and Department of Physiology, School of Biomedical Sciences, University of New South Wales, Sydney, NSW, Australia
- Research Beyond Borders, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Germany
| | - Gary D. Housley
- Translational Neuroscience Facility and Department of Physiology, School of Biomedical Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Dominik Fröhlich
- Translational Neuroscience Facility and Department of Physiology, School of Biomedical Sciences, University of New South Wales, Sydney, NSW, Australia
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Panzeri E, Citterio A, Martinuzzi A, Ancona V, Martini E, Bassi MT. Case report: A novel FARS2 deletion and a missense variant in a child with complicated, rapidly progressive spastic paraplegia. Front Genet 2023; 14:1130687. [PMID: 37152989 PMCID: PMC10154595 DOI: 10.3389/fgene.2023.1130687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 03/23/2023] [Indexed: 05/09/2023] Open
Abstract
Defects in FARS2 are associated with either epileptic phenotypes or a spastic paraplegia subtype known as SPG77. Here, we describe an 8-year-old patient with severe and complicated spastic paraplegia, carrying a missense variant (p.Pro361Leu) and a novel intragenic deletion in FARS2. Of note, the disease is unexpectedly progressing rapidly and in a biphasic way differently from the previously reported cases. Our study provides the first detailed molecular characterization of a FARS2 deletion and its underlying molecular mechanism, and demonstrates the need for combining different tools to improve the diagnostic rate.
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Affiliation(s)
- Elena Panzeri
- Laboratory of Molecular Biology, Scientific Institute IRCCS E. Medea, Bosisio Parini, Italy
- *Correspondence: Elena Panzeri,
| | - Andrea Citterio
- Laboratory of Molecular Biology, Scientific Institute IRCCS E. Medea, Bosisio Parini, Italy
| | - Andrea Martinuzzi
- Department of Neurorehabilitation, Scientific Institute IRCCS E. Medea, Conegliano, Italy
| | - Vera Ancona
- Department of Neurorehabilitation, Scientific Institute IRCCS E. Medea, Conegliano, Italy
| | - Eleonora Martini
- Department of Neurorehabilitation, Scientific Institute IRCCS E. Medea, Conegliano, Italy
| | - Maria Teresa Bassi
- Laboratory of Molecular Biology, Scientific Institute IRCCS E. Medea, Bosisio Parini, Italy
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Meng F, Jia Z, Zheng J, Ji Y, Wang J, Xiao Y, Fu Y, Wang M, Ling F, Guan MX. A deafness-associated mitochondrial DNA mutation caused pleiotropic effects on DNA replication and tRNA metabolism. Nucleic Acids Res 2022; 50:9453-9469. [PMID: 36039763 PMCID: PMC9458427 DOI: 10.1093/nar/gkac720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Accepted: 08/09/2022] [Indexed: 12/24/2022] Open
Abstract
In this report, we investigated the molecular mechanism underlying a deafness-associated m.5783C > T mutation that affects the canonical C50-G63 base-pairing of TΨC stem of tRNACys and immediately adjacent to 5' end of light-strand origin of mitochondrial DNA (mtDNA) replication (OriL). Two dimensional agarose gel electrophoresis revealed marked decreases in the replication intermediates including ascending arm of Y-fork arcs spanning OriL in the mutant cybrids bearing m.5783C > T mutation. mtDNA replication alterations were further evidenced by decreased levels of PolγA, Twinkle and SSBP1, newly synthesized mtDNA and mtDNA contents in the mutant cybrids. The m.5783C > T mutation altered tRNACys structure and function, including decreased melting temperature, conformational changes, instability and deficient aminoacylation of mutated tRNACys. The m.5783C > T mutation impaired the 5' end processing efficiency of tRNACys precursors and reduced the levels of tRNACys and downstream tRNATyr. The aberrant tRNA metabolism impaired mitochondrial translation, which was especially pronounced effects in the polypeptides harboring higher numbers of cysteine and tyrosine codons. These alterations led to deficient oxidative phosphorylation including instability and reduced activities of the respiratory chain enzyme complexes I, III, IV and intact supercomplexes overall. Our findings highlight the impact of mitochondrial dysfunction on deafness arising from defects in mitochondrial DNA replication and tRNA metabolism.
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Affiliation(s)
| | | | - Jing Zheng
- Division of Medical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, Zhejiang, China,Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China,Zhejiang Provincial Key Lab of Genetic and Developmental Disorder, Hangzhou, Zhejiang, China
| | - Yanchun Ji
- Division of Medical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, Zhejiang, China,Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China,Zhejiang Provincial Key Lab of Genetic and Developmental Disorder, Hangzhou, Zhejiang, China
| | - Jing Wang
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Yun Xiao
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Yong Fu
- Division of Otolaryngology-Head and Neck Surgery, The Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Meng Wang
- Division of Medical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, Zhejiang, China,Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China,Zhejiang Provincial Key Lab of Genetic and Developmental Disorder, Hangzhou, Zhejiang, China
| | - Feng Ling
- Chemical Genomics Research Group, RIKEN Center for Sustainable Resource Science, Hirosawa 2-1, Wako, Saitama, Japan
| | - Min-Xin Guan
- To whom correspondence should be addressed. Tel: +86 571 88206916; Fax: +86 571 88982377;
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Jia Z, Meng F, Chen H, Zhu G, Li X, He Y, Zhang L, He X, Zhan H, Chen M, Ji Y, Wang M, Guan MX. Human TRUB1 is a highly conserved pseudouridine synthase responsible for the formation of Ψ55 in mitochondrial tRNAAsn, tRNAGln, tRNAGlu and tRNAPro. Nucleic Acids Res 2022; 50:9368-9381. [PMID: 36018806 PMCID: PMC9458420 DOI: 10.1093/nar/gkac698] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 07/26/2022] [Accepted: 07/30/2022] [Indexed: 12/24/2022] Open
Abstract
Pseudouridine (Ψ) at position 55 in tRNAs plays an important role in their structure and function. This modification is catalyzed by TruB/Pus4/Cbf5 family of pseudouridine synthases in bacteria and yeast. However, the mechanism of TRUB family underlying the formation of Ψ55 in the mammalian tRNAs is largely unknown. In this report, the CMC/reverse transcription assays demonstrated the presence of Ψ55 in the human mitochondrial tRNAAsn, tRNAGln, tRNAGlu, tRNAPro, tRNAMet, tRNALeu(UUR) and tRNASer(UCN). TRUB1 knockout (KO) cell lines generated by CRISPR/Cas9 technology exhibited the loss of Ψ55 modification in mitochondrial tRNAAsn, tRNAGln, tRNAGlu and tRNAPro but did not affect other 18 mitochondrial tRNAs. An in vitro assay revealed that recombinant TRUB1 protein can catalyze the efficient formation of Ψ55 in tRNAAsn and tRNAGln, but not in tRNAMet and tRNAArg. Notably, the overexpression of TRUB1 cDNA reversed the deficient Ψ55 modifications in these tRNAs in TRUB1KO HeLa cells. TRUB1 deficiency affected the base-pairing (18A/G-Ψ55), conformation and stability but not aminoacylation capacity of these tRNAs. Furthermore, TRUB1 deficiency impacted mitochondrial translation and biogenesis of oxidative phosphorylation system. Our findings demonstrated that human TRUB1 is a highly conserved mitochondrial pseudouridine synthase responsible for the Ψ55 modification in the mitochondrial tRNAAsn, tRNAGln, tRNAGlu and tRNAPro.
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Affiliation(s)
| | | | | | - Gao Zhu
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Xincheng Li
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Yunfan He
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Liyao Zhang
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Xiao He
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Huisen Zhan
- 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
| | - Yanchun Ji
- Division of Medical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, Zhejiang, China,Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Meng Wang
- Division of Medical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, Zhejiang, China,Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Min-Xin Guan
- To whom correspondence should be addressed. Tel: +571 88206916; Fax: +571 88982377;
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11
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Liang M, Ji C, Zhang L, Wang X, Hu C, Zhang J, Zhu Y, Mo JQ, Guan MX. Leber's hereditary optic neuropathy (LHON)-associated ND6 14 484 T > C mutation caused pleiotropic effects on the complex I, RNA homeostasis, apoptosis and mitophagy. Hum Mol Genet 2022; 31:3299-3312. [PMID: 35567411 DOI: 10.1093/hmg/ddac109] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 04/25/2022] [Accepted: 05/09/2022] [Indexed: 11/12/2022] Open
Abstract
Leber's hereditary optic neuropathy (LHON) is a maternally inherited eye disease due to mitochondrial DNA (mtDNA) mutations. LHON-linked ND6 14 484 T > C (p.M64V) mutation affected structural components of complex I but its pathophysiology is poorly understood. The structural analysis of complex I revealed that the M64 forms a nonpolar interaction Y59 in the ND6, Y59 in the ND6 interacts with E34 of ND4L, and L60 of ND6 interacts with the Y114 of ND1. These suggested that the m.14484 T > C mutation may perturb the structure and function of complex I. Mutant cybrids constructed by transferring mitochondria from lymphoblastoid cell lines of one Chinese LHON family into mtDNA-less (ρo) cells revealed decreases in the levels of ND6, ND1 and ND4L. The m.14484 T > C mutation may affect mitochondrial mRNA homeostasis, supported by reduced levels of SLIRP and SUPV3L1 involved in mRNA degradation and increasing expression of ND6, ND1 and ND4L genes. These alterations yielded decreased activity of complex I, respiratory deficiency, diminished mitochondrial ATP production and reduced membrane potential, and increased production of reactive oxygen species in the mutant cybrids. Furthermore, the m.14484 T > C mutation promoted apoptosis, evidenced by elevating Annexin V-positive cells, release of cytochrome c into cytosol, levels in apoptotic proteins BAX, caspases 3, 7, 9 and decreasing levels in anti-apoptotic protein Bcl-xL in the mutant cybrids. Moreover, the cybrids bearing the m.14484 T > C mutation exhibited the reduced levels of autophagy protein LC3, increased levels of substrate P62 and impaired PINK1/Parkin-dependent mitophagy. Our findings highlighted the critical role of m.14484 T > C mutation in the pathogenesis of LHON.
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Affiliation(s)
- Min Liang
- Department of Medical Laboratory, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, China.,Attardi Institute of Mitochondrial Biomedicine, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China.,Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Chun Ji
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, 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 310058, China
| | - Liyao Zhang
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Xuan Wang
- Attardi Institute of Mitochondrial Biomedicine, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Cuifang Hu
- Attardi Institute of Mitochondrial Biomedicine, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Juanjuan Zhang
- Attardi Institute of Mitochondrial Biomedicine, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China.,School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325027, China
| | - Yiwei Zhu
- Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Jun Q Mo
- Department of Pathology, Rady Children's Hospital, University of California at San Diego School of Medicine, San Diego, California 92123, USA
| | - Min-Xin Guan
- Attardi Institute of Mitochondrial Biomedicine, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China.,Institute of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, 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 310058, China.,Zhejiang Provincial Key Laboratory of Genetic & Developmental Disorders, Hangzhou, Zhejiang 310058, China
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