1
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Saurer M, Leibundgut M, Nadimpalli HP, Scaiola A, Schönhut T, Lee RG, Siira SJ, Rackham O, Dreos R, Lenarčič T, Kummer E, Gatfield D, Filipovska A, Ban N. Molecular basis of translation termination at noncanonical stop codons in human mitochondria. Science 2023; 380:531-536. [PMID: 37141370 DOI: 10.1126/science.adf9890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The genetic code that specifies the identity of amino acids incorporated into proteins during protein synthesis is almost universally conserved. Mitochondrial genomes feature deviations from the standard genetic code, including the reassignment of two arginine codons to stop codons. The protein required for translation termination at these noncanonical stop codons to release the newly synthesized polypeptides is not currently known. In this study, we used gene editing and ribosomal profiling in combination with cryo-electron microscopy to establish that mitochondrial release factor 1 (mtRF1) detects noncanonical stop codons in human mitochondria by a previously unknown mechanism of codon recognition. We discovered that binding of mtRF1 to the decoding center of the ribosome stabilizes a highly unusual conformation in the messenger RNA in which the ribosomal RNA participates in specific recognition of the noncanonical stop codons.
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Affiliation(s)
- Martin Saurer
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland
| | - Marc Leibundgut
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland
| | | | - Alain Scaiola
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland
| | - Tanja Schönhut
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland
| | - Richard G Lee
- Harry Perkins Institute of Medical Research, The University of Western Australia, Nedlands, Western Australia 6009, Australia
- ARC Centre of Excellence in Synthetic Biology, QEII Medical Centre, The University of Western Australia, Nedlands, Western Australia 6009, Australia
- Telethon Kids Institute, Northern Entrance, Perth Children's Hospital, 15 Hospital Avenue, Nedlands, Western Australia, Australia
| | - Stefan J Siira
- Harry Perkins Institute of Medical Research, The University of Western Australia, Nedlands, Western Australia 6009, Australia
- ARC Centre of Excellence in Synthetic Biology, QEII Medical Centre, The University of Western Australia, Nedlands, Western Australia 6009, Australia
| | - Oliver Rackham
- Harry Perkins Institute of Medical Research, The University of Western Australia, Nedlands, Western Australia 6009, Australia
- ARC Centre of Excellence in Synthetic Biology, QEII Medical Centre, The University of Western Australia, Nedlands, Western Australia 6009, Australia
- Telethon Kids Institute, Northern Entrance, Perth Children's Hospital, 15 Hospital Avenue, Nedlands, Western Australia, Australia
- Curtin Medical School and Curtin Health Innovation Research Institute, Curtin University, Bentley, Western Australia 6102, Australia
| | - René Dreos
- Center for Integrative Genomics, University of Lausanne, 1015 Lausanne, Switzerland
| | - Tea Lenarčič
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland
| | - Eva Kummer
- Novo Nordisk Foundation Center for Protein Research, Protein Structure and Function Program, Blegdamsvej 3B, 2200 København N, Denmark
| | - David Gatfield
- Center for Integrative Genomics, University of Lausanne, 1015 Lausanne, Switzerland
| | - Aleksandra Filipovska
- Harry Perkins Institute of Medical Research, The University of Western Australia, Nedlands, Western Australia 6009, Australia
- ARC Centre of Excellence in Synthetic Biology, QEII Medical Centre, The University of Western Australia, Nedlands, Western Australia 6009, Australia
- Telethon Kids Institute, Northern Entrance, Perth Children's Hospital, 15 Hospital Avenue, Nedlands, Western Australia, Australia
| | - Nenad Ban
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland
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2
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Boughanem H, Böttcher Y, Tomé-Carneiro J, López de Las Hazas MC, Dávalos A, Cayir A, Macias-González M. The emergent role of mitochondrial RNA modifications in metabolic alterations. WILEY INTERDISCIPLINARY REVIEWS. RNA 2023; 14:e1753. [PMID: 35872632 DOI: 10.1002/wrna.1753] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 06/14/2022] [Accepted: 06/27/2022] [Indexed: 11/11/2022]
Abstract
Mitochondrial epitranscriptomics refers to the modifications occurring in all the different RNA types of mitochondria. Although the number of mitochondrial RNA modifications is less than those in cytoplasm, substantial evidence indicates that they play a critical role in accurate protein synthesis. Recent evidence supported those modifications in mitochondrial RNAs also have crucial implications in mitochondrial-related diseases. In the light of current knowledge about the involvement, the association between mitochondrial RNA modifications and diseases arises from studies focusing on mutations in both mitochondrial and nuclear DNA genes encoding enzymes involved in such modifications. Here, we review the current evidence available for mitochondrial RNA modifications and their role in metabolic disorders, and we also explore the possibility of using them as promising targets for prevention and early detection. Finally, we discuss future directions of mitochondrial epitranscriptomics in these metabolic alterations, and how these RNA modifications may offer a new diagnostic and theragnostic avenue for preventive purposes. This article is categorized under: RNA Processing > RNA Editing and Modification.
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Affiliation(s)
- Hatim Boughanem
- Instituto de Investigación Biomédica de Málaga (IBIMA), Unidad de Gestión Clínica de Endocrinología y Nutrición del Hospital Virgen de la Victoria and University of Málaga, Spain.,Instituto de Salud Carlos III (ISCIII), Consorcio CIBER, M.P. Fisiopatología de la Obesidad y Nutrición (CIBERObn), Madrid, Spain
| | - Yvonne Böttcher
- Institute of Clinical Medicine, Department of Clinical Molecular Biology, University of Oslo, Oslo, Norway.,Akershus Universitetssykehus, Medical Department, Lørenskog, Norway
| | - João Tomé-Carneiro
- Laboratory of Functional Foods, Madrid Institute for Advanced Studies (IMDEA)-Food, CEI UAM + CSIC, Madrid, Spain
| | - María-Carmen López de Las Hazas
- Laboratory of Epigenetics of Lipid Metabolism, Madrid Institute for Advanced Studies (IMDEA)-Food, CEI UAM + CSIC, Madrid, Spain
| | - Alberto Dávalos
- Laboratory of Epigenetics of Lipid Metabolism, Madrid Institute for Advanced Studies (IMDEA)-Food, CEI UAM + CSIC, Madrid, Spain
| | - Akin Cayir
- Vocational Health College, Canakkale Onsekiz Mart University, Canakkale, Turkey.,Clinical Molecular Biology (EpiGen), Division of Medicine, Akershus Universitetssykehus, Lørenskog, Norway
| | - Manuel Macias-González
- Instituto de Investigación Biomédica de Málaga (IBIMA), Unidad de Gestión Clínica de Endocrinología y Nutrición del Hospital Virgen de la Victoria and University of Málaga, Spain.,Instituto de Salud Carlos III (ISCIII), Consorcio CIBER, M.P. Fisiopatología de la Obesidad y Nutrición (CIBERObn), Madrid, Spain
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3
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Kachale A, Pavlíková Z, Nenarokova A, Roithová A, Durante IM, Miletínová P, Záhonová K, Nenarokov S, Votýpka J, Horáková E, Ross RL, Yurchenko V, Beznosková P, Paris Z, Valášek LS, Lukeš J. Short tRNA anticodon stem and mutant eRF1 allow stop codon reassignment. Nature 2023; 613:751-758. [PMID: 36631608 DOI: 10.1038/s41586-022-05584-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 11/18/2022] [Indexed: 01/13/2023]
Abstract
Cognate tRNAs deliver specific amino acids to translating ribosomes according to the standard genetic code, and three codons with no cognate tRNAs serve as stop codons. Some protists have reassigned all stop codons as sense codons, neglecting this fundamental principle1-4. Here we analyse the in-frame stop codons in 7,259 predicted protein-coding genes of a previously undescribed trypanosomatid, Blastocrithidia nonstop. We reveal that in this species in-frame stop codons are underrepresented in genes expressed at high levels and that UAA serves as the only termination codon. Whereas new tRNAsGlu fully cognate to UAG and UAA evolved to reassign these stop codons, the UGA reassignment followed a different path through shortening the anticodon stem of tRNATrpCCA from five to four base pairs (bp). The canonical 5-bp tRNATrp recognizes UGG as dictated by the genetic code, whereas its shortened 4-bp variant incorporates tryptophan also into in-frame UGA. Mimicking this evolutionary twist by engineering both variants from B. nonstop, Trypanosoma brucei and Saccharomyces cerevisiae and expressing them in the last two species, we recorded a significantly higher readthrough for all 4-bp variants. Furthermore, a gene encoding B. nonstop release factor 1 acquired a mutation that specifically restricts UGA recognition, robustly potentiating the UGA reassignment. Virtually the same strategy has been adopted by the ciliate Condylostoma magnum. Hence, we describe a previously unknown, universal mechanism that has been exploited in unrelated eukaryotes with reassigned stop codons.
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Affiliation(s)
- Ambar Kachale
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic.,Faculty of Sciences, University of South Bohemia, České Budějovice, Czech Republic
| | - Zuzana Pavlíková
- Institute of Microbiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Anna Nenarokova
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic.,Faculty of Sciences, University of South Bohemia, České Budějovice, Czech Republic.,School of Biological Sciences, University of Bristol, Bristol, UK
| | - Adriana Roithová
- Institute of Microbiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Ignacio M Durante
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Petra Miletínová
- Institute of Microbiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Kristína Záhonová
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic.,Faculty of Science, Charles University, BIOCEV, Prague, Czech Republic.,Life Science Research Centre, Faculty of Science, University of Ostrava, Ostrava, Czech Republic
| | - Serafim Nenarokov
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic.,Faculty of Sciences, University of South Bohemia, České Budějovice, Czech Republic
| | - Jan Votýpka
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic.,Faculty of Science, Charles University, BIOCEV, Prague, Czech Republic
| | - Eva Horáková
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic.,Institute of Microbiology, Czech Academy of Sciences, Třeboň, Czech Republic
| | | | - Vyacheslav Yurchenko
- Life Science Research Centre, Faculty of Science, University of Ostrava, Ostrava, Czech Republic
| | - Petra Beznosková
- Institute of Microbiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Zdeněk Paris
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic. .,Faculty of Sciences, University of South Bohemia, České Budějovice, Czech Republic.
| | | | - Julius Lukeš
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic. .,Faculty of Sciences, University of South Bohemia, České Budějovice, Czech Republic.
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4
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Zhu J, Kuang J, Yang Y, Zhang L, Leng B, She R, Zou L. A Prognostic Model Based on NSUN3 Was Established to Evaluate the Prognosis and Response to Immunotherapy in Liver Hepatocellular Carcinoma. Mediators Inflamm 2023; 2023:6645476. [PMID: 37114236 PMCID: PMC10129436 DOI: 10.1155/2023/6645476] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Revised: 03/07/2023] [Accepted: 03/31/2023] [Indexed: 04/29/2023] Open
Abstract
It is difficult for traditional therapies to further improve the prognosis of hepatocellular carcinoma (LIHC), and immunotherapy is considered to be a promising approach to overcome this dilemma. However, only a minority of patients benefit from immunotherapy, which greatly limits its application. Therefore, it is particularly urgent to elucidate the specific regulatory mechanism of tumor immunity so as to provide a new direction for immunotherapy. NOP2/Sun RNA methyltransferase 3 (NSUN3) is a protein with RNA binding and methyltransferase activity, which has been shown to be involved in the occurrence and development of a variety of tumors. At present, the relationship between NSUN3 and immune implication in LIHC has not been reported. In this study, we first revealed that NSUN3 expression is upregulated in LIHC and that patients with high NSUN3 expression have a poor prognosis through multiple databases. Pathway enrichment analysis demonstrated that NSUN3 may be participated in cell adhesion and cell matrix remodeling. Next, we obtained a set of genes coexpressed with NSUN3 (NCGs). Further LASSO regression was performed based on NCGs, and a risk score model was constructed, which proved to have good predictive power. In addition, Cox regression analysis revealed that the risk score of NCGs model was an independent risk factor for LIHC patients. Moreover, we established a nomogram based on the NCGs-related model, which was verified to have a good predictive ability for the prognosis of LIHC. Furthermore, we investigated the relationship between NCGs-related model and immune implication. The results implied that our model was closely related to immune score, immune cell infiltration, immunotherapy response, and multiple immune checkpoints. Finally, the pathway enrichment analysis of NCGs-related model showed that the model may be involved in the regulation of various immune pathways. In conclusion, our study revealed a novel role of NSUN3 in LIHC. The NSUN3-based prognostic model may be a promising biomarker for inspecting the prognosis and immunotherapy response of LIHC.
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Affiliation(s)
- Jianlin Zhu
- Dongguan Institute of Clinical Cancer Research, The Tenth Affiliated Hospital of Southern Medical University, China
- Dongguan Key Laboratory of Precision Diagnosis and Treatment for Tumors, The Tenth Affiliated Hospital of Southern Medical University, China
| | - Junxi Kuang
- Department of Cardiovascular Medicine, The Third Affiliated Hospital of Sun Yat-sen University, China
- Department of Emergency, The Tenth Affiliated Hospital of Southern Medical University, China
| | - Yi Yang
- Dongguan Institute of Clinical Cancer Research, The Tenth Affiliated Hospital of Southern Medical University, China
- Dongguan Key Laboratory of Precision Diagnosis and Treatment for Tumors, The Tenth Affiliated Hospital of Southern Medical University, China
| | - Lei Zhang
- Dongguan Institute of Clinical Cancer Research, The Tenth Affiliated Hospital of Southern Medical University, China
| | - Bo Leng
- Dongguan Institute of Clinical Cancer Research, The Tenth Affiliated Hospital of Southern Medical University, China
| | - Risheng She
- Dongguan Institute of Clinical Cancer Research, The Tenth Affiliated Hospital of Southern Medical University, China
- Department of Emergency, The Tenth Affiliated Hospital of Southern Medical University, China
| | - Ling Zou
- Dongguan Institute of Clinical Cancer Research, The Tenth Affiliated Hospital of Southern Medical University, China
- Dongguan Key Laboratory of Precision Diagnosis and Treatment for Tumors, The Tenth Affiliated Hospital of Southern Medical University, China
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5
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Itoh Y, Khawaja A, Laptev I, Cipullo M, Atanassov I, Sergiev P, Rorbach J, Amunts A. Mechanism of mitoribosomal small subunit biogenesis and preinitiation. Nature 2022; 606:603-608. [PMID: 35676484 PMCID: PMC9200640 DOI: 10.1038/s41586-022-04795-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Accepted: 04/22/2022] [Indexed: 12/27/2022]
Abstract
Mitoribosomes are essential for the synthesis and maintenance of bioenergetic proteins. Here we use cryo-electron microscopy to determine a series of the small mitoribosomal subunit (SSU) intermediates in complex with auxiliary factors, revealing a sequential assembly mechanism. The methyltransferase TFB1M binds to partially unfolded rRNA h45 that is promoted by RBFA, while the mRNA channel is blocked. This enables binding of METTL15 that promotes further rRNA maturation and a large conformational change of RBFA. The new conformation allows initiation factor mtIF3 to already occupy the subunit interface during the assembly. Finally, the mitochondria-specific ribosomal protein mS37 (ref. 1) outcompetes RBFA to complete the assembly with the SSU-mS37-mtIF3 complex2 that proceeds towards mtIF2 binding and translation initiation. Our results explain how the action of step-specific factors modulate the dynamic assembly of the SSU, and adaptation of a unique protein, mS37, links the assembly to initiation to establish the catalytic human mitoribosome.
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Affiliation(s)
- Yuzuru Itoh
- Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, Solna, Sweden
| | - Anas Khawaja
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
- Max Planck Institute for Biology of Ageing-Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Ivan Laptev
- Center of Life Sciences, Skolkovo Institute of Science and Technology, Moscow, Russia
- Department of Chemistry, Lomonosov Moscow State University, Moscow, Russia
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Miriam Cipullo
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
- Max Planck Institute for Biology of Ageing-Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Ilian Atanassov
- Proteomics Core Facility, Max-Planck-Institute for Biology of Ageing, Cologne, Germany
| | - Petr Sergiev
- Center of Life Sciences, Skolkovo Institute of Science and Technology, Moscow, Russia
- Department of Chemistry, Lomonosov Moscow State University, Moscow, Russia
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
- Institute of Functional Genomics, Lomonosov Moscow State University, Moscow, Russia
| | - Joanna Rorbach
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden.
- Max Planck Institute for Biology of Ageing-Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden.
| | - Alexey Amunts
- Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, Solna, Sweden.
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6
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Biological roles of RNA m 5C modification and its implications in Cancer immunotherapy. Biomark Res 2022; 10:15. [PMID: 35365216 PMCID: PMC8973801 DOI: 10.1186/s40364-022-00362-8] [Citation(s) in RCA: 60] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 03/03/2022] [Indexed: 01/08/2023] Open
Abstract
Epigenetics including DNA and RNA modifications have always been the hotspot field of life sciences in the post-genome era. Since the first mapping of N6-methyladenosine (m6A) and the discovery of its widespread presence in mRNA, there are at least 160-170 RNA modifications have been discovered. These methylations occur in different RNA types, and their distribution is species-specific. 5-methylcytosine (m5C) has been found in mRNA, rRNA and tRNA of representative organisms from all kinds of species. As reversible epigenetic modifications, m5C modifications of RNA affect the fate of the modified RNA molecules and play important roles in various biological processes including RNA stability control, protein synthesis, and transcriptional regulation. Furthermore, accumulative evidence also implicates the role of RNA m5C in tumorigenesis. Here, we review the latest progresses in the biological roles of m5C modifications and how it is regulated by corresponding “writers”, “readers” and “erasers” proteins, as well as the potential molecular mechanism in tumorigenesis and cancer immunotherapy.
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7
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Li A, Sun X, Arguello AE, Kleiner RE. Chemical Method to Sequence 5-Formylcytosine on RNA. ACS Chem Biol 2022; 17:503-508. [PMID: 35212224 PMCID: PMC9357364 DOI: 10.1021/acschembio.1c00707] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Epitranscriptomic RNA modifications can regulate biological processes, but there remains a major gap in our ability to identify and measure individual modifications at nucleotide resolution. Here we present Mal-Seq, a chemical method for sequencing 5-formylcytosine (f5C) modifications on RNA based on the selective and efficient malononitrile-mediated labeling of f5C residues to generate adducts that are read as C-to-T mutations upon reverse transcription and polymerase chain reaction amplification. We apply Mal-Seq to characterize the prevalence of f5C at the wobble position of mt-tRNA(Met) in different organisms and tissue types and find that high-level f5C modification is present in mammals but lacking in lower eukaryotes. Our work sheds light on mitochondrial tRNA modifications throughout eukaryotic evolution and provides a general platform for characterizing the f5C epitranscriptome.
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Affiliation(s)
- Ang Li
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Xuemeng Sun
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - A Emilia Arguello
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Ralph E Kleiner
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
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8
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Laricchia KM, Lake NJ, Watts NA, Shand M, Haessly A, Gauthier L, Benjamin D, Banks E, Soto J, Garimella K, Emery J, Rehm HL, MacArthur DG, Tiao G, Lek MV, Mootha VK, Calvo SE. Mitochondrial DNA variation across 56,434 individuals in gnomAD. Genome Res 2022; 32:569-582. [PMID: 35074858 PMCID: PMC8896463 DOI: 10.1101/gr.276013.121] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 01/19/2022] [Indexed: 11/25/2022]
Abstract
Genomic databases of allele frequency are extremely helpful for evaluating clinical variants of unknown significance; however, until now, databases such as the Genome Aggregation Database (gnomAD) have focused on nuclear DNA and have ignored the mitochondrial genome (mtDNA). Here we present a pipeline to call mtDNA variants that addresses three technical challenges: (i) detecting homoplasmic and heteroplasmic variants, present respectively in all or a fraction of mtDNA molecules, (ii) circular mtDNA genome, and (iii) misalignment of nuclear sequences of mitochondrial origin (NUMTs). We observed that mtDNA copy number per cell varied across gnomAD cohorts and influenced the fraction of NUMT-derived false-positive variant calls, which can account for the majority of putative heteroplasmies. To avoid false positives, we excluded contaminated samples, cell lines, and samples prone to NUMT misalignment due to few mtDNA copies. Furthermore, we report variants with heteroplasmy greater than 10%. We applied this pipeline to 56,434 whole genome sequences in the gnomAD v3.1 database that includes individuals of European (58%), African (25%), Latino (10%), and Asian (5%) ancestry. Our gnomAD v3.1 release contains population frequencies for 10,850 unique mtDNA variants at more than half of all mtDNA bases. We report frequencies within each nuclear ancestral population and mitochondrial haplogroup. Homoplasmic variants account for most variant calls (98%) and unique variants (85%). We observed that 1/250 individuals carry a pathogenic mtDNA variant with heteroplasmy above 10%. These mtDNA population allele frequencies are freely accessible and will aid in diagnostic interpretation and research studies.
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9
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Manduzio S, Kang H. RNA methylation in chloroplasts or mitochondria in plants. RNA Biol 2021; 18:2127-2135. [PMID: 33779501 PMCID: PMC8632092 DOI: 10.1080/15476286.2021.1909321] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 03/23/2021] [Indexed: 12/14/2022] Open
Abstract
Recent advances in our understanding of epitranscriptomic RNA methylation have expanded the complexity of gene expression regulation beyond epigenetic regulation involving DNA methylation and histone modifications. The instalment, removal, and interpretation of methylation marks on RNAs are carried out by writers (methyltransferases), erasers (demethylases), and readers (RNA-binding proteins), respectively. Contrary to an emerging body of evidence demonstrating the importance of RNA methylation in the diverse fates of RNA molecules, including splicing, export, translation, and decay in the nucleus and cytoplasm, their roles in plant organelles remain largely unclear and are only now being discovered. In particular, extremely high levels of methylation marks in chloroplast and mitochondrial RNAs suggest that RNA methylation plays essential roles in organellar biogenesis and functions in plants that are crucial for plant development and responses to environmental stimuli. Thus, unveiling the cellular components involved in RNA methylation in cell organelles is essential to better understand plant biology.
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Affiliation(s)
- Stefano Manduzio
- Department of Applied Biology, College of Agriculture and Life Sciences, Chonnam National University, Gwangju, South Korea
| | - Hunseung Kang
- Department of Applied Biology, College of Agriculture and Life Sciences, Chonnam National University, Gwangju, South Korea
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10
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Lan C, Wu Y, Wang N, Luo Y, Zhao J, Zheng Y, Zhang Y, Huang L, Zhu Y, Lu L, Zhong W, Zeng J, Xia H. Association between ABHD1 and DOK6 polymorphisms and susceptibility to Hirschsprung disease in Southern Chinese children. J Cell Mol Med 2021; 25:9609-9616. [PMID: 34545688 PMCID: PMC8505836 DOI: 10.1111/jcmm.16905] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 07/26/2021] [Accepted: 08/04/2021] [Indexed: 12/31/2022] Open
Abstract
Hirschsprung disease (HSCR) is an infrequent congenital intestinal dysplasia. The known genetic variations are unable to fully explain the pathogenesis of HSCR. The α/β‐hydratase domain 1 (ABHD1) interferes with the proliferation and migration of intestinal stem cells. Docking protein 6 (DOK6) is involved in neurodevelopment through RET signalling pathway. We examined the association of ABHD1 and DOK6 genetic variants with HSCR using 1470 controls and 1473 HSCR patients from Southern Chinese children. The results clarified that DOK6 rs12968648 G allele significantly increased HSCR susceptibility, in the allelic model (p = 0.034; OR = 1.12, 95%CI = 1.01~1.24) and the dominant model (p = 0.038; OR = 1.12, 95%CI = 1.01~1.25). Clinical stratification analysis showed that rs12968648 G allele was associated with increased risk of short‐segment HSCR (S‐HSCR), in the allelic model (p = 0.028; OR = 1.14, 95%CI = 1.01~1.28) and the additive model (p = 0.030; OR = 1.14, 95%CI = 1.01~1.28). ABHD1 rs2304678 C allele had higher risk to develop total colonic aganglionosis (TCA) in the allelic model (p = 7.04E‐03; OR = 1.67, 95%CI = 1.15~2.43) and the dominant model (p = 4.12E‐03; OR = 1.93, 95%CI = 1.23~3.04). DOK6 rs12968648 and ABHD1 rs2304678 had significant intergenic synergistic effect according to logical regression (p = 0.0081; OR = 0.76, 95%CI = 0.63~0.93) and multifactor dimensionality reduction (MDR, p = 0.0045; OR = 1.25, 95%CI = 1.07~1.46). This study verified two susceptible variations of HSCR on ABHD1 and DOK6. Their roles in HSCR should be conducted in further studies.
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Affiliation(s)
- Chaoting Lan
- The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Yuxin Wu
- The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Ning Wang
- Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Yun Luo
- Department of Neonatology, Guangzhou Baiyunshan Hospital, Guangzhou, Guangdong, China
| | - Jinglu Zhao
- Department of Pediatric Surgery, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Yi Zheng
- Department of Pediatric Surgery, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Yan Zhang
- Department of Pediatric Surgery, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Lihua Huang
- Department of Pediatric Surgery, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Yun Zhu
- Department of Pediatric Surgery, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Lifeng Lu
- Department of Pediatric Surgery, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Wei Zhong
- Department of Pediatric Surgery, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Jixiao Zeng
- Department of Pediatric Surgery, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Huimin Xia
- The First Affiliated Hospital of Jinan University, Guangzhou, China.,Department of Pediatric Surgery, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
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11
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Van Haute L, Minczuk M. Detection of 5-formylcytosine in Mitochondrial Transcriptome. Methods Mol Biol 2021; 2192:59-68. [PMID: 33230765 DOI: 10.1007/978-1-0716-0834-0_5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Posttranscriptional RNA modifications have recently emerged as essential posttranscriptional regulators of gene expression. Here we present two methods for single nucleotide resolution detection of 5-formylcytosine (f5C) in RNA. The first relies on chemical protection of f5C against bisulfite treatment, the second method is based on chemical reduction of f5C to hm5C. In combination with regular bisulfite treatment of RNA, the methods allow for precise mapping of f5C. The protocol is used for f5C detection in mtDNA-encoded RNA, however, it can be straightforwardly applied for transcriptome-wide analyses.
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Affiliation(s)
- Lindsey Van Haute
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK.
| | - Michal Minczuk
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK.
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12
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Bennett JP, Onyango IG. Energy, Entropy and Quantum Tunneling of Protons and Electrons in Brain Mitochondria: Relation to Mitochondrial Impairment in Aging-Related Human Brain Diseases and Therapeutic Measures. Biomedicines 2021; 9:225. [PMID: 33671585 PMCID: PMC7927033 DOI: 10.3390/biomedicines9020225] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 02/18/2021] [Accepted: 02/18/2021] [Indexed: 11/16/2022] Open
Abstract
Adult human brains consume a disproportionate amount of energy substrates (2-3% of body weight; 20-25% of total glucose and oxygen). Adenosine triphosphate (ATP) is a universal energy currency in brains and is produced by oxidative phosphorylation (OXPHOS) using ATP synthase, a nano-rotor powered by the proton gradient generated from proton-coupled electron transfer (PCET) in the multi-complex electron transport chain (ETC). ETC catalysis rates are reduced in brains from humans with neurodegenerative diseases (NDDs). Declines of ETC function in NDDs may result from combinations of nitrative stress (NS)-oxidative stress (OS) damage; mitochondrial and/or nuclear genomic mutations of ETC/OXPHOS genes; epigenetic modifications of ETC/OXPHOS genes; or defects in importation or assembly of ETC/OXPHOS proteins or complexes, respectively; or alterations in mitochondrial dynamics (fusion, fission, mitophagy). Substantial free energy is gained by direct O2-mediated oxidation of NADH. Traditional ETC mechanisms require separation between O2 and electrons flowing from NADH/FADH2 through the ETC. Quantum tunneling of electrons and much larger protons may facilitate this separation. Neuronal death may be viewed as a local increase in entropy requiring constant energy input to avoid. The ATP requirement of the brain may partially be used for avoidance of local entropy increase. Mitochondrial therapeutics seeks to correct deficiencies in ETC and OXPHOS.
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Affiliation(s)
| | - Isaac G. Onyango
- International Clinical Research Center, St. Anne’s University Hospital, CZ-65691 Brno, Czech Republic;
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13
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Shetty S, Varshney U. Regulation of translation by one-carbon metabolism in bacteria and eukaryotic organelles. J Biol Chem 2021; 296:100088. [PMID: 33199376 PMCID: PMC7949028 DOI: 10.1074/jbc.rev120.011985] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 11/15/2020] [Accepted: 11/16/2020] [Indexed: 12/20/2022] Open
Abstract
Protein synthesis is an energetically costly cellular activity. It is therefore important that the process of mRNA translation remains in excellent synchrony with cellular metabolism and its energy reserves. Unregulated translation could lead to the production of incomplete, mistranslated, or misfolded proteins, squandering the energy needed for cellular sustenance and causing cytotoxicity. One-carbon metabolism (OCM), an integral part of cellular intermediary metabolism, produces a number of one-carbon unit intermediates (formyl, methylene, methenyl, methyl). These OCM intermediates are required for the production of amino acids such as methionine and other biomolecules such as purines, thymidylate, and redox regulators. In this review, we discuss how OCM impacts the translation apparatus (composed of ribosome, tRNA, mRNA, and translation factors) and regulates crucial steps in protein synthesis. More specifically, we address how the OCM metabolites regulate the fidelity and rate of translation initiation in bacteria and eukaryotic organelles such as mitochondria. Modulation of the fidelity of translation initiation by OCM opens new avenues to understand alternative translation mechanisms involved in stress tolerance and drug resistance.
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Affiliation(s)
- Sunil Shetty
- Biozentrum, University of Basel, Basel, Switzerland
| | - Umesh Varshney
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India; Jawaharlal Nehru Centre for Advanced Scientific Studies, Jakkur, Bangalore, India.
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14
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iPSC-derived homogeneous populations of developing schizophrenia cortical interneurons have compromised mitochondrial function. Mol Psychiatry 2020; 25:2873-2888. [PMID: 31019265 PMCID: PMC6813882 DOI: 10.1038/s41380-019-0423-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2018] [Revised: 03/23/2019] [Accepted: 04/03/2019] [Indexed: 02/05/2023]
Abstract
Schizophrenia (SCZ) is a neurodevelopmental disorder. Thus, studying pathogenetic mechanisms underlying SCZ requires studying the development of brain cells. Cortical interneurons (cINs) are consistently observed to be abnormal in SCZ postmortem brains. These abnormalities may explain altered gamma oscillation and cognitive function in patients with SCZ. Of note, currently used antipsychotic drugs ameliorate psychosis, but they are not very effective in reversing cognitive deficits. Characterizing mechanisms of SCZ pathogenesis, especially related to cognitive deficits, may lead to improved treatments. We generated homogeneous populations of developing cINs from 15 healthy control (HC) iPSC lines and 15 SCZ iPSC lines. SCZ cINs, but not SCZ glutamatergic neurons, show dysregulated Oxidative Phosphorylation (OxPhos) related gene expression, accompanied by compromised mitochondrial function. The OxPhos deficit in cINs could be reversed by Alpha Lipoic Acid/Acetyl-L-Carnitine (ALA/ALC) but not by other chemicals previously identified as increasing mitochondrial function. The restoration of mitochondrial function by ALA/ALC was accompanied by a reversal of arborization deficits in SCZ cINs. OxPhos abnormality, even in the absence of any circuit environment with other neuronal subtypes, appears to be an intrinsic deficit in SCZ cINs.
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15
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Dubini RCA, Schön A, Müller M, Carell T, Rovó P. Impact of 5-formylcytosine on the melting kinetics of DNA by 1H NMR chemical exchange. Nucleic Acids Res 2020; 48:8796-8807. [PMID: 32652019 PMCID: PMC7470965 DOI: 10.1093/nar/gkaa589] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Revised: 06/24/2020] [Accepted: 07/02/2020] [Indexed: 12/23/2022] Open
Abstract
5-Formylcytosine (5fC) is a chemically edited, naturally occurring nucleobase which appears in the context of modified DNA strands. The understanding of the impact of 5fC on dsDNA physical properties is to date limited. In this work, we applied temperature-dependent 1H Chemical Exchange Saturation Transfer (CEST) NMR experiments to non-invasively and site-specifically measure the thermodynamic and kinetic influence of formylated cytosine nucleobase on the melting process involving dsDNA. Incorporation of 5fC within symmetrically positioned CpG sites destabilizes the whole dsDNA structure-as witnessed from the ∼2°C decrease in the melting temperature and 5-10 kJ mol-1 decrease in ΔG°-and affects the kinetic rates of association and dissociation. We observed an up to ∼5-fold enhancement of the dsDNA dissociation and an up to ∼3-fold reduction in ssDNA association rate constants, over multiple temperatures and for several proton reporters. Eyring and van't Hoff analysis proved that the destabilization is not localized, instead all base-pairs are affected and the transition states resembles the single-stranded conformation. These results advance our knowledge about the role of 5fC as a semi-permanent epigenetic modification and assist in the understanding of its interactions with reader proteins.
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Affiliation(s)
- Romeo C A Dubini
- Faculty of Chemistry and Pharmacy, Department of Chemistry, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377 Munich, Germany
- Center for Nanoscience (CeNS), Faculty of Physics, Ludwig-Maximilians-Universität München, Schellingstraße 4, 80799 Munich, Germany
| | - Alexander Schön
- Faculty of Chemistry and Pharmacy, Department of Chemistry, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377 Munich, Germany
| | - Markus Müller
- Faculty of Chemistry and Pharmacy, Department of Chemistry, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377 Munich, Germany
| | - Thomas Carell
- Faculty of Chemistry and Pharmacy, Department of Chemistry, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377 Munich, Germany
| | - Petra Rovó
- Faculty of Chemistry and Pharmacy, Department of Chemistry, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377 Munich, Germany
- Center for Nanoscience (CeNS), Faculty of Physics, Ludwig-Maximilians-Universität München, Schellingstraße 4, 80799 Munich, Germany
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16
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Boguszewska K, Szewczuk M, Kaźmierczak-Barańska J, Karwowski BT. The Similarities between Human Mitochondria and Bacteria in the Context of Structure, Genome, and Base Excision Repair System. Molecules 2020; 25:E2857. [PMID: 32575813 PMCID: PMC7356350 DOI: 10.3390/molecules25122857] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 06/17/2020] [Accepted: 06/19/2020] [Indexed: 02/06/2023] Open
Abstract
Mitochondria emerged from bacterial ancestors during endosymbiosis and are crucial for cellular processes such as energy production and homeostasis, stress responses, cell survival, and more. They are the site of aerobic respiration and adenosine triphosphate (ATP) production in eukaryotes. However, oxidative phosphorylation (OXPHOS) is also the source of reactive oxygen species (ROS), which are both important and dangerous for the cell. Human mitochondria contain mitochondrial DNA (mtDNA), and its integrity may be endangered by the action of ROS. Fortunately, human mitochondria have repair mechanisms that allow protecting mtDNA and repairing lesions that may contribute to the occurrence of mutations. Mutagenesis of the mitochondrial genome may manifest in the form of pathological states such as mitochondrial, neurodegenerative, and/or cardiovascular diseases, premature aging, and cancer. The review describes the mitochondrial structure, genome, and the main mitochondrial repair mechanism (base excision repair (BER)) of oxidative lesions in the context of common features between human mitochondria and bacteria. The authors present a holistic view of the similarities of mitochondria and bacteria to show that bacteria may be an interesting experimental model for studying mitochondrial diseases, especially those where the mechanism of DNA repair is impaired.
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Affiliation(s)
| | | | | | - Bolesław T. Karwowski
- DNA Damage Laboratory of Food Science Department, Faculty of Pharmacy, Medical University of Lodz, ul. Muszynskiego 1, 90-151 Lodz, Poland; (K.B.); (M.S.); (J.K.-B.)
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17
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McCown PJ, Ruszkowska A, Kunkler CN, Breger K, Hulewicz JP, Wang MC, Springer NA, Brown JA. Naturally occurring modified ribonucleosides. WILEY INTERDISCIPLINARY REVIEWS-RNA 2020; 11:e1595. [PMID: 32301288 PMCID: PMC7694415 DOI: 10.1002/wrna.1595] [Citation(s) in RCA: 96] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2020] [Revised: 03/09/2020] [Accepted: 03/11/2020] [Indexed: 12/18/2022]
Abstract
The chemical identity of RNA molecules beyond the four standard ribonucleosides has fascinated scientists since pseudouridine was characterized as the “fifth” ribonucleotide in 1951. Since then, the ever‐increasing number and complexity of modified ribonucleosides have been found in viruses and throughout all three domains of life. Such modifications can be as simple as methylations, hydroxylations, or thiolations, complex as ring closures, glycosylations, acylations, or aminoacylations, or unusual as the incorporation of selenium. While initially found in transfer and ribosomal RNAs, modifications also exist in messenger RNAs and noncoding RNAs. Modifications have profound cellular outcomes at various levels, such as altering RNA structure or being essential for cell survival or organism viability. The aberrant presence or absence of RNA modifications can lead to human disease, ranging from cancer to various metabolic and developmental illnesses such as Hoyeraal–Hreidarsson syndrome, Bowen–Conradi syndrome, or Williams–Beuren syndrome. In this review article, we summarize the characterization of all 143 currently known modified ribonucleosides by describing their taxonomic distributions, the enzymes that generate the modifications, and any implications in cellular processes, RNA structure, and disease. We also highlight areas of active research, such as specific RNAs that contain a particular type of modification as well as methodologies used to identify novel RNA modifications. This article is categorized under:RNA Processing > RNA Editing and Modification
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Affiliation(s)
- Phillip J McCown
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Agnieszka Ruszkowska
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Charlotte N Kunkler
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Kurtis Breger
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Jacob P Hulewicz
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Matthew C Wang
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Noah A Springer
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Jessica A Brown
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
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18
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Trixl L, Lusser A. The dynamic RNA modification 5-methylcytosine and its emerging role as an epitranscriptomic mark. WILEY INTERDISCIPLINARY REVIEWS-RNA 2018; 10:e1510. [PMID: 30311405 PMCID: PMC6492194 DOI: 10.1002/wrna.1510] [Citation(s) in RCA: 189] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 08/30/2018] [Accepted: 09/17/2018] [Indexed: 12/11/2022]
Abstract
It is a well‐known fact that RNA is the target of a plethora of modifications which currently amount to over a hundred. The vast majority of these modifications was observed in the two most abundant classes of RNA, rRNA and tRNA. With the recent advance in mapping technologies, modifications have been discovered also in mRNA and in less abundant non‐coding RNA species. These developments have sparked renewed interest in elucidating the nature and functions of those “epitransciptomic” modifications in RNA. N6‐methyladenosine (m6A) is the best understood and most frequent mark of mRNA with demonstrated functions ranging from pre‐mRNA processing, translation, miRNA biogenesis to mRNA decay. By contrast, much less research has been conducted on 5‐methylcytosine (m5C), which was detected in tRNAs and rRNAs and more recently in poly(A)RNAs. In this review, we discuss recent developments in the discovery of m5C RNA methylomes, the functions of m5C as well as the proteins installing, translating and manipulating this modification. Although our knowledge about m5C in RNA transcripts is just beginning to consolidate, it has become clear that cytosine methylation represents a powerful mechanistic strategy to regulate cellular processes on an epitranscriptomic level. This article is categorized under:RNA Processing > RNA Editing and Modification RNA Interactions with Proteins and Other Molecules > Protein–RNA Interactions: Functional Implications RNA Processing > tRNA Processing RNA Turnover and Surveillance > Regulation of RNA Stability
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Affiliation(s)
- Lukas Trixl
- Division of Molecular Biology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
| | - Alexandra Lusser
- Division of Molecular Biology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
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19
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Mitochondrial transcription and translation: overview. Essays Biochem 2018; 62:309-320. [PMID: 30030363 PMCID: PMC6056719 DOI: 10.1042/ebc20170102] [Citation(s) in RCA: 165] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 05/14/2018] [Accepted: 05/14/2018] [Indexed: 12/13/2022]
Abstract
Mitochondria are the major source of ATP in the cell. Five multi-subunit complexes in the inner membrane of the organelle are involved in the oxidative phosphorylation required for ATP production. Thirteen subunits of these complexes are encoded by the mitochondrial genome often referred to as mtDNA. For this reason, the expression of mtDNA is vital for the assembly and functioning of the oxidative phosphorylation complexes. Defects of the mechanisms regulating mtDNA gene expression have been associated with deficiencies in assembly of these complexes, resulting in mitochondrial diseases. Recently, numerous factors involved in these processes have been identified and characterized leading to a deeper understanding of the mechanisms that underlie mitochondrial diseases.
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20
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Agris PF, Eruysal ER, Narendran A, Väre VYP, Vangaveti S, Ranganathan SV. Celebrating wobble decoding: Half a century and still much is new. RNA Biol 2017; 15:537-553. [PMID: 28812932 PMCID: PMC6103715 DOI: 10.1080/15476286.2017.1356562] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 07/04/2017] [Accepted: 07/06/2017] [Indexed: 10/25/2022] Open
Abstract
A simple post-transcriptional modification of tRNA, deamination of adenosine to inosine at the first, or wobble, position of the anticodon, inspired Francis Crick's Wobble Hypothesis 50 years ago. Many more naturally-occurring modifications have been elucidated and continue to be discovered. The post-transcriptional modifications of tRNA's anticodon domain are the most diverse and chemically complex of any RNA modifications. Their contribution with regards to chemistry, structure and dynamics reveal individual and combined effects on tRNA function in recognition of cognate and wobble codons. As forecast by the Modified Wobble Hypothesis 25 years ago, some individual modifications at tRNA's wobble position have evolved to restrict codon recognition whereas others expand the tRNA's ability to read as many as four synonymous codons. Here, we review tRNA wobble codon recognition using specific examples of simple and complex modification chemistries that alter tRNA function. Understanding natural modifications has inspired evolutionary insights and possible innovation in protein synthesis.
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Affiliation(s)
- Paul F. Agris
- The RNA Institute, State University of New York, Albany, NY, USA
- Department of Biology, State University of New York, Albany, NY, USA
- Department of Chemistry, State University of New York, Albany, NY, USA
| | - Emily R. Eruysal
- Department of Biology, State University of New York, Albany, NY, USA
| | - Amithi Narendran
- Department of Biology, State University of New York, Albany, NY, USA
| | - Ville Y. P. Väre
- Department of Biology, State University of New York, Albany, NY, USA
| | - Sweta Vangaveti
- The RNA Institute, State University of New York, Albany, NY, USA
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