1
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Yahya V, Dilena R, Del Bo R, Magni M, Biella F, Salani S, Fortunato F, Scola E, Di Fonzo A, Monfrini E. Soft cerebellar signs unveil RARS2-related epilepsy. Epileptic Disord 2024. [PMID: 38733322 DOI: 10.1002/epd2.20237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 03/30/2024] [Accepted: 04/22/2024] [Indexed: 05/13/2024]
Affiliation(s)
- Vidal Yahya
- Dino Ferrari Center, Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Robertino Dilena
- Neurophysiopathology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Roberto Del Bo
- Dino Ferrari Center, Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Manuela Magni
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Fabio Biella
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Sabrina Salani
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Francesco Fortunato
- Dino Ferrari Center, Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Elisa Scola
- Neuroradiology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Alessio Di Fonzo
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Edoardo Monfrini
- Dino Ferrari Center, Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
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2
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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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3
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Guang S, O'Brien BM, Fine AS, Ying M, Fatemi A, Nemeth CL. Mutations in DARS2 result in global dysregulation of mRNA metabolism and splicing. Sci Rep 2023; 13:13042. [PMID: 37563224 PMCID: PMC10415389 DOI: 10.1038/s41598-023-40107-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Accepted: 08/04/2023] [Indexed: 08/12/2023] Open
Abstract
Leukoencephalopathy with brainstem and spinal cord involvement and lactate elevation (LBSL) is a rare neurological disorder caused by the mutations in the DARS2 gene, which encodes the mitochondrial aspartyl-tRNA synthetase. The objective of this study was to understand the impact of DARS2 mutations on cell processes through evaluation of LBSL patient stem cell derived cerebral organoids and neurons. We generated human cerebral organoids (hCOs) from induced pluripotent stem cells (iPSCs) of seven LBSL patients and three healthy controls using an unguided protocol. Single cells from 70-day-old hCOs were subjected to SMART-seq2 sequencing and bioinformatic analysis to acquire high-resolution gene and transcript expression datasets. Global gene expression analysis demonstrated dysregulation of a number of genes involved in mRNA metabolism and splicing processes within LBSL hCOs. Importantly, there were distinct and divergent gene expression profiles based on the nature of the DARS2 mutation. At the transcript level, pervasive differential transcript usage and differential spliced exon events that are involved in protein translation and metabolism were identified in LBSL hCOs. Single-cell analysis of DARS2 (exon 3) showed that some LBSL cells exclusively express transcripts lacking exon 3, indicating that not all LBSL cells can benefit from the "leaky" nature common to splice site mutations. At the gene- and transcript-level, we uncovered that dysregulated RNA splicing, protein translation and metabolism may underlie at least some of the pathophysiological mechanisms in LBSL. To confirm hCO findings, iPSC-derived neurons (iNs) were generated by overexpressing Neurogenin 2 using lentiviral vector to study neuronal growth, splicing of DARS2 exon 3 and DARS2 protein expression. Live cell imaging revealed neuronal growth defects of LBSL iNs, which was consistent with the finding of downregulated expression of genes related to neuronal differentiation in LBSL hCOs. DARS2 protein was downregulated in iNs compared to iPSCs, caused by increased exclusion of exon 3. The scope and complexity of our data imply that DARS2 is potentially involved in transcription regulation beyond its canonical role of aminoacylation. Nevertheless, our work highlights transcript-level dysregulation as a critical, and relatively unexplored, mechanism linking genetic data with neurodegenerative disorders.
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Affiliation(s)
- S Guang
- Moser Center for Leukodystrophies at Kennedy Krieger, Kennedy Krieger Institute, 707 N Broadway, Baltimore, MD, 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - B M O'Brien
- Moser Center for Leukodystrophies at Kennedy Krieger, Kennedy Krieger Institute, 707 N Broadway, Baltimore, MD, 21205, USA
| | - A S Fine
- Department of Neurology and Developmental Medicine, Kennedy Krieger Institute, Baltimore, MD, USA
| | - M Ying
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Department of Neurology, Kennedy Krieger Institute, Baltimore, MD, USA
| | - A Fatemi
- Moser Center for Leukodystrophies at Kennedy Krieger, Kennedy Krieger Institute, 707 N Broadway, Baltimore, MD, 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - C L Nemeth
- Moser Center for Leukodystrophies at Kennedy Krieger, Kennedy Krieger Institute, 707 N Broadway, Baltimore, MD, 21205, USA.
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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4
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Guang S, O'Brien B, Fine AS, Ying M, Fatemi A, Nemeth C. Mutations in DARS2 result in global dysregulation of mRNA metabolism and splicing. RESEARCH SQUARE 2023:rs.3.rs-2603446. [PMID: 36909591 PMCID: PMC10002802 DOI: 10.21203/rs.3.rs-2603446/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
Abstract
Leukoencephalopathy with brain stem and spinal cord involvement and lactate elevation (LBSL) is a rare neurological disorder caused by the mutations in the DARS2 gene, which encodes the mitochondrial aspartyl-tRNA synthetase. The objective of this study was to understand the impact of DARS2 mutations on cell processes through evaluation of LBSL patient stem cell derived cerebral organoids and neurons. We generated human cerebral organoids (hCOs) from induced pluripotent stem cells (iPSCs) of seven LBSL patients and three healthy controls using an unguided protocol. Single cells from 70-day-old hCOs underwent SMART-seq2 sequencing and multiple bioinformatic analysis tools were applied to high-resolution gene and transcript expression analyses. To confirm hCO findings, iPSC-derived neurons (iNs) were generated by overexpressing Neurogenin 2 using lentiviral vector to study neuronal growth, splicing of DARS2 exon 3 and DARS2 protein expression. Global gene expression analysis demonstrated dysregulation of a number of genes involved in mRNA metabolism and splicing processes within LBSL hCOs. Importantly, there were distinct and divergent gene expression profiles based on the nature of the DARS2 mutation. At the transcript level, pervasive differential transcript usage and differential spliced exon events that are involved in protein translation and metabolism were identified in LBSL hCOs. Single-cell analysis of DARS2 (exon 3) showed that some LBSL cells exclusively express transcripts lacking exon 3, indicating that not all LBSL cells can benefit from the "leaky" nature common to splice site mutations. Live cell imaging revealed neuronal growth defects of LBSL iNs, which was consistent with the finding of downregulated expression of genes related to neuronal differentiation in LBSL hCOs. DARS2 protein was downregulated in iNs compared to iPSCs, caused by increased exclusion of exon 3. At the gene- and transcript-level, we uncovered that dysregulated RNA splicing, protein translation and metabolism may underlie at least some of the pathophysiological mechanisms in LBSL. The scope and complexity of our data imply that DARS2 is potentially involved in transcription regulation beyond its canonical role of aminoacylation. Nevertheless, our work highlights transcript-level dysregulation as a critical, and relatively unexplored, mechanism linking genetic data with neurodegenerative disorders.
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Affiliation(s)
- Shiqi Guang
- Moser Center for Leukodystrophies at Kennedy Krieger, Kennedy Krieger Institute
| | - Brett O'Brien
- Moser Center for Leukodystrophies at Kennedy Krieger, Kennedy Krieger Institute
| | - Amena Smith Fine
- Moser Center for Leukodystrophies at Kennedy Krieger, Kennedy Krieger Institute
| | | | - Ali Fatemi
- Moser Center for Leukodystrophies at Kennedy Krieger, Kennedy Krieger Institute
| | - Christina Nemeth
- Moser Center for Leukodystrophies at Kennedy Krieger, Kennedy Krieger Institute
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5
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Peng GX, Mao XL, Cao Y, Yao SY, Li QR, Chen X, Wang ED, Zhou XL. RNA granule-clustered mitochondrial aminoacyl-tRNA synthetases form multiple complexes with the potential to fine-tune tRNA aminoacylation. Nucleic Acids Res 2022; 50:12951-12968. [PMID: 36503967 PMCID: PMC9825176 DOI: 10.1093/nar/gkac1141] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 10/23/2022] [Accepted: 11/15/2022] [Indexed: 12/14/2022] Open
Abstract
Mitochondrial RNA metabolism is suggested to occur in identified compartmentalized foci, i.e. mitochondrial RNA granules (MRGs). Mitochondrial aminoacyl-tRNA synthetases (mito aaRSs) catalyze tRNA charging and are key components in mitochondrial gene expression. Mutations of mito aaRSs are associated with various human disorders. However, the suborganelle distribution, interaction network and regulatory mechanism of mito aaRSs remain largely unknown. Here, we found that all mito aaRSs partly colocalize with MRG, and this colocalization is likely facilitated by tRNA-binding capacity. A fraction of human mitochondrial AlaRS (hmtAlaRS) and hmtSerRS formed a direct complex via interaction between catalytic domains in vivo. Aminoacylation activities of both hmtAlaRS and hmtSerRS were fine-tuned upon complex formation in vitro. We further established a full spectrum of interaction networks via immunoprecipitation and mass spectrometry for all mito aaRSs and discovered interactions between hmtSerRS and hmtAsnRS, between hmtSerRS and hmtTyrRS and between hmtThrRS and hmtArgRS. The activity of hmtTyrRS was also influenced by the presence of hmtSerRS. Notably, hmtSerRS utilized the same catalytic domain in mediating several interactions. Altogether, our results systematically analyzed the suborganelle localization and interaction network of mito aaRSs and discovered several mito aaRS-containing complexes, deepening our understanding of the functional and regulatory mechanisms of mito aaRSs.
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Affiliation(s)
| | | | - Yating Cao
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen 361102, China
| | - Shi-Ying Yao
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Qing-Run Li
- CAS Key Laboratory of Systems Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Xin Chen
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen 361102, China
| | - En-Duo Wang
- Correspondence may also be addressed to En-Duo Wang. Tel: +86 21 5492 1241; Fax: +86 21 5492 1011;
| | - Xiao-Long Zhou
- To whom correspondence should be addressed. Tel: +86 21 5492 1247; Fax: +86 21 5492 1011;
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6
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Del Greco C, Antonellis A. The Role of Nuclear-Encoded Mitochondrial tRNA Charging Enzymes in Human Inherited Disease. Genes (Basel) 2022; 13:genes13122319. [PMID: 36553587 PMCID: PMC9777667 DOI: 10.3390/genes13122319] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 11/30/2022] [Accepted: 12/02/2022] [Indexed: 12/13/2022] Open
Abstract
Aminoacyl-tRNA synthetases (ARSs) are highly conserved essential enzymes that charge tRNA with cognate amino acids-the first step of protein synthesis. Of the 37 nuclear-encoded human ARS genes, 17 encode enzymes are exclusively targeted to the mitochondria (mt-ARSs). Mutations in nuclear mt-ARS genes are associated with rare, recessive human diseases with a broad range of clinical phenotypes. While the hypothesized disease mechanism is a loss-of-function effect, there is significant clinical heterogeneity among patients that have mutations in different mt-ARS genes and also among patients that have mutations in the same mt-ARS gene. This observation suggests that additional factors are involved in disease etiology. In this review, we present our current understanding of diseases caused by mutations in the genes encoding mt-ARSs and propose explanations for the observed clinical heterogeneity.
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Affiliation(s)
- Christina Del Greco
- 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
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
- Correspondence:
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7
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Roux CJ, Barcia G, Schiff M, Sissler M, Levy R, Dangouloff-Ros V, Desguerre I, Edvardson S, Elpeleg O, Rötig A, Munnich A, Boddaert N. Phenotypic diversity of brain MRI patterns in mitochondrial aminoacyl-tRNA synthetase mutations. Mol Genet Metab 2021; 133:222-229. [PMID: 33972171 DOI: 10.1016/j.ymgme.2021.04.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 02/15/2021] [Accepted: 04/16/2021] [Indexed: 12/16/2022]
Abstract
BACKGROUND AND PURPOSE Mitochondrial aminoacyl-tRNA synthetases-encoded by ARS2 genes-are evolutionarily conserved enzymes that catalyse the attachment of amino acids to their cognate tRNAs, ensuring the accuracy of the mitochondrial translation process. ARS2 gene mutations are associated with a wide range of clinical presentations affecting the CNS. METHODS Two senior neuroradiologists analysed brain MRI of 25 patients (age range: 3 d-25 yrs.; 11 males; 14 females) with biallelic pathogenic variants of 11 ARS2 genes in a retrospective study conducted between 2002 and 2019. RESULTS Though several combinations of brain MRI anomalies were highly suggestive of specific aetiologies (DARS2, EARS2, AARS2 and RARS2 mutations), our study detected no MRI pattern common to all patients. Stroke-like lesions were associated with pathogenic SARS2 and FARS2 variants. We also report early onset cerebellar atrophy and calcifications in AARS2 mutations, early white matter involvement in RARS2 mutations, and absent involvement of thalami in EARS2 mutations. Finally, our findings show that normal brain MRI results do not exclude the presence of ARS2 mutations: 5 patients with normal MRI images were carriers of pathogenic IARS2, YARS2, and FARS2 variants. CONCLUSION Our study extends the spectrum of brain MRI anomalies associated with pathogenic ARS2 variants and suggests ARS2 mutations are largely underdiagnosed.
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Affiliation(s)
- Charles-Joris Roux
- Department of Paediatric Radiology, Hôpital Necker-Enfants Malades, Paris, France.
| | - Giulia Barcia
- Department of Genetics, Hospital Necker-Enfants Malades, Paris, France
| | - Manuel Schiff
- Institut Imagine, INSERM UMR 1163, Paris, France; Necker Hospital, APHP, Reference Center for Inborn Error of Metabolism, Pediatrics Department, University of Paris, Paris, France
| | - Marie Sissler
- Institut Européen de Chimie et Biologie, INSERM U1212, CNRS UMR 5320, University of Bordeaux, Pessac, France
| | - Raphaël Levy
- Department of Paediatric Radiology, Hôpital Necker-Enfants Malades, Paris, France
| | | | - Isabelle Desguerre
- Department of Neurology and Metabolism, Hôpital Necker-Enfants Malades, Paris, France
| | - Shimon Edvardson
- Department of Genetics, Hadassah University Hospital, Jerusalem, Israel
| | - Orli Elpeleg
- Department of Genetics, Hadassah University Hospital, Jerusalem, Israel
| | - Agnès Rötig
- Institut Imagine, INSERM UMR 1163, Paris, France
| | - Arnold Munnich
- Department of Genetics, Hospital Necker-Enfants Malades, Paris, France; Institut Imagine, INSERM UMR 1163, Paris, France
| | - Nathalie Boddaert
- Department of Paediatric Radiology, Hôpital Necker-Enfants Malades, Paris, France; Institut Imagine, INSERM UMR 1163, Paris, France
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8
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Muthiah A, Housley GD, Klugmann M, Fröhlich D. The Leukodystrophies HBSL and LBSL-Correlates and Distinctions. Front Cell Neurosci 2021; 14:626610. [PMID: 33574740 PMCID: PMC7870476 DOI: 10.3389/fncel.2020.626610] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Accepted: 12/21/2020] [Indexed: 12/16/2022] Open
Abstract
Aminoacyl-tRNA synthetases (ARSs) accurately charge tRNAs with their respective amino acids. As such, they are vital for the initiation of cytosolic and mitochondrial protein translation. These enzymes have become increasingly scrutinized in recent years for their role in neurodegenerative disorders caused by the mutations of ARS-encoding genes. This review focuses on two such genes-DARS1 and DARS2-which encode cytosolic and mitochondrial aspartyl-tRNA synthetases, and the clinical conditions associated with mutations of these genes. We also describe attempts made at modeling these conditions in mice, which have both yielded important mechanistic insights. Leukoencephalopathy with brainstem and spinal cord involvement and lactate elevation (LBSL) is a disease caused by a range of mutations in the DARS2 gene, initially identified in 2003. Ten years later, hypomyelination with brainstem and spinal cord involvement and leg spasticity (HBSL), caused by mutations of cytosolic DARS1, was discovered. Multiple parallels have been drawn between the two conditions. The Magnetic Resonance Imaging (MRI) patterns are strikingly similar, but still set these two conditions apart from other leukodystrophies. Clinically, both conditions are characterized by lower limb spasticity, often associated with other pyramidal signs. However, perhaps due to earlier detection, a wider range of symptoms, including peripheral neuropathy, as well as visual and hearing changes have been described in LBSL patients. Both HBSL and LBSL are spectrum disorders lacking genotype to phenotype correlation. While the fatal phenotype of Dars1 or Dars2 single gene deletion mouse mutants revealed that the two enzymes lack functional redundancy, further pursuit of disease modeling are required to shed light onto the underlying disease mechanism, and enable examination of experimental treatments, including gene therapies.
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Affiliation(s)
| | | | | | - Dominik Fröhlich
- Translational Neuroscience Facility and Department of Physiology, School of Medical Sciences, UNSW Sydney, Kensington, NSW, Australia
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9
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A patient with pontocerebellar hypoplasia type 6: Novel RARS2 mutations, comparison to previously published patients and clinical distinction from PEHO syndrome. Eur J Med Genet 2020; 63:103766. [DOI: 10.1016/j.ejmg.2019.103766] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 09/15/2019] [Accepted: 09/15/2019] [Indexed: 12/15/2022]
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10
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Mitochondrial aminoacyl-tRNA synthetases. Enzymes 2020. [PMID: 33837704 DOI: 10.1016/bs.enz.2020.07.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/29/2023]
Abstract
In all eukaryotic cells, protein synthesis occurs not only in the cytosol, but also in the mitochondria. Translation of mitochondrial genes requires a set of aminoacyl-tRNA synthetases, many of which are often specialized for organellar function. These enzymes have evolved unique mechanisms for tRNA recognition and for ensuring fidelity of translation. Mutations of human mitochondrial synthetases are associated with a wide range of pathogenic phenotypes, both highlighting the importance of their role in maintaining the cellular "powerhouse" and suggesting additional cellular roles.
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11
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Florentz C, Giegé R. History of tRNA research in strasbourg. IUBMB Life 2019; 71:1066-1087. [PMID: 31185141 DOI: 10.1002/iub.2079] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 05/06/2019] [Indexed: 01/03/2023]
Abstract
The tRNA molecules, in addition to translating the genetic code into protein and defining the second genetic code via their aminoacylation by aminoacyl-tRNA synthetases, act in many other cellular functions and dysfunctions. This article, illustrated by personal souvenirs, covers the history of ~60 years tRNA research in Strasbourg. Typical examples point up how the work in Strasbourg was a two-way street, influenced by and at the same time influencing investigators outside of France. All along, research in Strasbourg has nurtured the structural and functional diversity of tRNA. It produced massive sequence and crystallographic data on tRNA and its partners, thereby leading to a deeper physicochemical understanding of tRNA architecture, dynamics, and identity. Moreover, it emphasized the role of nucleoside modifications and in the last two decades, highlighted tRNA idiosyncrasies in plants and organelles, together with cellular and health-focused aspects. The tRNA field benefited from a rich local academic heritage and a strong support by both university and CNRS. Its broad interlinks to the worldwide community of tRNA researchers opens to an exciting future. © 2019 IUBMB Life, 2019 © 2019 IUBMB Life, 71(8):1066-1087, 2019.
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Affiliation(s)
- Catherine Florentz
- Architecture et Réactivité de l'ARN, UPR 9002, Institut de Biologie Moléculaire et Cellulaire, CNRS and Université de Strasbourg, F-67084, 15 rue René Descartes, Strasbourg, France.,Direction de la Recherche et de la Valorisation, Université de Strasbourg, F-67084, 4 rue Blaise Pascal, Strasbourg, France
| | - Richard Giegé
- Architecture et Réactivité de l'ARN, UPR 9002, Institut de Biologie Moléculaire et Cellulaire, CNRS and Université de Strasbourg, F-67084, 15 rue René Descartes, Strasbourg, France
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12
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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] [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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