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Pierpont CL, Baroch JJ, Church MJ, Miller SR. Idiosyncratic genome evolution of the thermophilic cyanobacterium Synechococcus at the limits of phototrophy. THE ISME JOURNAL 2024; 18:wrae184. [PMID: 39319368 PMCID: PMC11456837 DOI: 10.1093/ismejo/wrae184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2024] [Revised: 08/19/2024] [Accepted: 09/23/2024] [Indexed: 09/26/2024]
Abstract
Thermophilic microorganisms are expected to have smaller cells and genomes compared with mesophiles, a higher proportion of horizontally acquired genes, and distinct nucleotide and amino acid composition signatures. Here, we took an integrative approach to investigate these apparent correlates of thermophily for Synechococcus A/B cyanobacteria, which include the most heat-tolerant phototrophs on the planet. Phylogenomics confirmed a unique origin of different thermotolerance ecotypes, with low levels of continued gene flow between ecologically divergent but overlapping populations, which has shaped the distribution of phenotypic traits along these geothermal gradients. More thermotolerant strains do have smaller genomes, but genome reduction is associated with a decrease in community richness and metabolic diversity, rather than with cell size. Horizontal gene transfer played only a limited role during Synechococcus evolution, but, the most thermotolerant strains have acquired a Thermus tRNA modification enzyme that may stabilize translation at high temperatures. Although nucleotide base composition was not associated with thermotolerance, we found a general replacement of aspartate with glutamate, as well as a dramatic remodeling of amino acid composition at the highest temperatures that substantially differed from previous predictions. We conclude that Synechococcus A/B genome diversification largely does not conform to the standard view of temperature adaptation. In addition, carbon fixation was more thermolabile than photosynthetic oxygen evolution for the most thermotolerant strains compared with less tolerant lineages. This suggests that increased flow of reducing power generated during the light reactions to an electron sink(s) beyond carbon dioxide has emerged during temperature adaptation of these bacteria.
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Affiliation(s)
- C Logan Pierpont
- Division of Biological Sciences, The University of Montana, 32 Campus Dr. #4824, Missoula, MT 59812, United States
| | - Jacob J Baroch
- Division of Biological Sciences, The University of Montana, 32 Campus Dr. #4824, Missoula, MT 59812, United States
| | - Matthew J Church
- Division of Biological Sciences, The University of Montana, 32 Campus Dr. #4824, Missoula, MT 59812, United States
| | - Scott R Miller
- Division of Biological Sciences, The University of Montana, 32 Campus Dr. #4824, Missoula, MT 59812, United States
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2
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Kohno Y, Ito A, Okamoto A, Yamagami R, Hirata A, Hori H. Escherichia coli tRNA (Gm18) methyltransferase (TrmH) requires the correct localization of its methylation site (G18) in the D-loop for efficient methylation. J Biochem 2023; 175:43-56. [PMID: 37844264 PMCID: PMC11640301 DOI: 10.1093/jb/mvad076] [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: 07/11/2023] [Revised: 09/08/2023] [Accepted: 09/27/2023] [Indexed: 10/18/2023] Open
Abstract
TrmH is a eubacterial tRNA methyltransferase responsible for formation of 2'-O-methylguaosine at position 18 (Gm18) in tRNA. In Escherichia coli cells, only 14 tRNA species possess the Gm18 modification. To investigate the substrate tRNA selection mechanism of E. coli TrmH, we performed biochemical and structural studies. Escherichia coli TrmH requires a high concentration of substrate tRNA for efficient methylation. Experiments using native tRNA SerCGA purified from a trmH gene disruptant strain showed that modified nucleosides do not affect the methylation. A gel mobility-shift assay reveals that TrmH captures tRNAs without distinguishing between relatively good and very poor substrates. Methylation assays using wild-type and mutant tRNA transcripts revealed that the location of G18 in the D-loop is very important for efficient methylation by E. coli TrmH. In the case of tRNASer, tRNATyrand tRNALeu, the D-loop structure formed by interaction with the long variable region is important. For tRNAGln, the short distance between G18 and A14 is important. Thus, our biochemical study explains all Gm18 modification patterns in E. coli tRNAs. The crystal structure of E. coli TrmH has also been solved, and the tRNA binding mode of E. coli TrmH is discussed based on the structure.
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Affiliation(s)
- Yoh Kohno
- Department of Materials Science and Biotechnology, Graduate school of Science and
Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime
790-8577, Japan
| | - Asako Ito
- Department of Materials Science and Biotechnology, Graduate school of Science and
Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime
790-8577, Japan
| | - Aya Okamoto
- Department of Materials Science and Biotechnology, Graduate school of Science and
Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime
790-8577, Japan
| | - Ryota Yamagami
- Department of Materials Science and Biotechnology, Graduate school of Science and
Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime
790-8577, Japan
| | - Akira Hirata
- Department of Natural Science, Graduate School of Technology, Industrial and Social
Science, Tokushima University, 2-1 Minamijosanjimacho,
Tokushima, Tokushima 770-8506, Japan
| | - Hiroyuki Hori
- Department of Materials Science and Biotechnology, Graduate school of Science and
Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime
790-8577, Japan
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3
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Dahlstrom TJ, Capraro DT, Jennings PA, Finke JM. Knotting Optimization and Folding Pathways of a Go-Model with a Deep Knot. J Phys Chem B 2022; 126:10221-10236. [PMID: 36424347 DOI: 10.1021/acs.jpcb.2c05588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Formation of protein knots is an intriguing offshoot of the protein folding problem. Since experimental resolution on knot formation is limited, theoretical methods currently provide the most detailed insights into the knotting process. While suitable for shallow knots, molecular dynamics simulations have faced challenges capturing the formation of deep knots in proteins such as the minimally tied trefoil α/β methyltransferase from Thermotoga maritima (MTTTM). To improve the efficiency of MTTTM knotting in Cα Go-model simulations, mutant variants of the MTTTM Go-model were investigated. Through a structure-based analysis of knotted and unknotted states, four residues (K71, R72, E75, V76) were identified to increase the knotting efficiency from 2% to 83% when their contact energies were doubled and dihedral strength around the knot loop increased. The key features of this model are (i) a C-terminal slipknot intermediate that threads the knot in a highly unstructured intermediate, (ii) the inability to knot in native-like intermediate states, and (iii) a minor population in a long-lived trap that cannot knot. Examination of residue 71-76 contacts provides a small set of potential mutants that can directly test the model's validity. In addition, the knotting optimization process developed here has broad applicability in generating knotting-efficient models of other knotted proteins.
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Affiliation(s)
- Thomas J Dahlstrom
- Division of Sciences and Mathematics, Interdisciplinary Arts and Sciences, University of Washington Tacoma, Tacoma, Washington98402, United States
| | - Dominique T Capraro
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California92093, United States
| | - Particia A Jennings
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California92093, United States
| | - John M Finke
- Division of Sciences and Mathematics, Interdisciplinary Arts and Sciences, University of Washington Tacoma, Tacoma, Washington98402, United States
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4
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Strassler SE, Bowles IE, Dey D, Jackman JE, Conn GL. Tied up in knots: Untangling substrate recognition by the SPOUT methyltransferases. J Biol Chem 2022; 298:102393. [PMID: 35988649 PMCID: PMC9508554 DOI: 10.1016/j.jbc.2022.102393] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 08/10/2022] [Accepted: 08/11/2022] [Indexed: 10/25/2022] Open
Abstract
The SpoU-TrmD (SPOUT) methyltransferase superfamily was designated when structural similarity was identified between the transfer RNA-modifying enzymes TrmH (SpoU) and TrmD. SPOUT methyltransferases are found in all domains of life and predominantly modify transfer RNA or ribosomal RNA substrates, though one instance of an enzyme with a protein substrate has been reported. Modifications placed by SPOUT methyltransferases play diverse roles in regulating cellular processes such as ensuring translational fidelity, altering RNA stability, and conferring bacterial resistance to antibiotics. This large collection of S-adenosyl-L-methionine-dependent methyltransferases is defined by a unique α/β fold with a deep trefoil knot in their catalytic (SPOUT) domain. Herein, we describe current knowledge of SPOUT enzyme structure, domain architecture, and key elements of catalytic function, including S-adenosyl-L-methionine co-substrate binding, beginning with a new sequence alignment that divides the SPOUT methyltransferase superfamily into four major clades. Finally, a major focus of this review will be on our growing understanding of how these diverse enzymes accomplish the molecular feat of specific substrate recognition and modification, as highlighted by recent advances in our knowledge of protein-RNA complex structures and the discovery of the dependence of one SPOUT methyltransferase on metal ion binding for catalysis. Considering the broad biological roles of RNA modifications, developing a deeper understanding of the process of substrate recognition by the SPOUT enzymes will be critical for defining many facets of fundamental RNA biology with implications for human disease.
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Affiliation(s)
- Sarah E Strassler
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia, USA; Graduate Program in Biochemistry, Cell and Developmental Biology, Graduate Division of Biological and Biomedical Sciences, Emory University, Atlanta, Georgia, USA
| | - Isobel E Bowles
- Department of Chemistry and Biochemistry, Center for RNA Biology and Ohio State Biochemistry Program, Columbus, Ohio, USA
| | - Debayan Dey
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Jane E Jackman
- Department of Chemistry and Biochemistry, Center for RNA Biology and Ohio State Biochemistry Program, Columbus, Ohio, USA.
| | - Graeme L Conn
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia, USA; Graduate Program in Biochemistry, Cell and Developmental Biology, Graduate Division of Biological and Biomedical Sciences, Emory University, Atlanta, Georgia, USA.
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5
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Kleiber N, Lemus-Diaz N, Stiller C, Heinrichs M, Mai MMQ, Hackert P, Richter-Dennerlein R, Höbartner C, Bohnsack KE, Bohnsack MT. The RNA methyltransferase METTL8 installs m 3C 32 in mitochondrial tRNAs Thr/Ser(UCN) to optimise tRNA structure and mitochondrial translation. Nat Commun 2022; 13:209. [PMID: 35017528 PMCID: PMC8752778 DOI: 10.1038/s41467-021-27905-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 12/14/2021] [Indexed: 12/30/2022] Open
Abstract
Modified nucleotides in tRNAs are important determinants of folding, structure and function. Here we identify METTL8 as a mitochondrial matrix protein and active RNA methyltransferase responsible for installing m3C32 in the human mitochondrial (mt-)tRNAThr and mt-tRNASer(UCN). METTL8 crosslinks to the anticodon stem loop (ASL) of many mt-tRNAs in cells, raising the question of how methylation target specificity is achieved. Dissection of mt-tRNA recognition elements revealed U34G35 and t6A37/(ms2)i6A37, present concomitantly only in the ASLs of the two substrate mt-tRNAs, as key determinants for METTL8-mediated methylation of C32. Several lines of evidence demonstrate the influence of U34, G35, and the m3C32 and t6A37/(ms2)i6A37 modifications in mt-tRNAThr/Ser(UCN) on the structure of these mt-tRNAs. Although mt-tRNAThr/Ser(UCN) lacking METTL8-mediated m3C32 are efficiently aminoacylated and associate with mitochondrial ribosomes, mitochondrial translation is mildly impaired by lack of METTL8. Together these results define the cellular targets of METTL8 and shed new light on the role of m3C32 within mt-tRNAs.
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MESH Headings
- Anticodon/chemistry
- Anticodon/metabolism
- Base Pairing
- Cytosine/metabolism
- Gene Expression Regulation
- HEK293 Cells
- Humans
- Methylation
- Methyltransferases/genetics
- Methyltransferases/metabolism
- Mitochondria/genetics
- Mitochondria/metabolism
- Nucleic Acid Conformation
- Protein Binding
- Protein Biosynthesis
- RNA, Mitochondrial/chemistry
- RNA, Mitochondrial/genetics
- RNA, Mitochondrial/metabolism
- RNA, Transfer, Ser/chemistry
- RNA, Transfer, Ser/genetics
- RNA, Transfer, Ser/metabolism
- RNA, Transfer, Thr/chemistry
- RNA, Transfer, Thr/genetics
- RNA, Transfer, Thr/metabolism
- Signal Transduction
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Affiliation(s)
- Nicole Kleiber
- Department of Molecular Biology, University Medical Centre Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
| | - Nicolas Lemus-Diaz
- Department of Molecular Biology, University Medical Centre Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
| | - Carina Stiller
- Institute of Organic Chemistry, Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Marleen Heinrichs
- Department of Cellular Biochemistry, University Medical Centre Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
| | - Mandy Mong-Quyen Mai
- Department of Cellular Biochemistry, University Medical Centre Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
| | - Philipp Hackert
- Department of Molecular Biology, University Medical Centre Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
| | - Ricarda Richter-Dennerlein
- Department of Cellular Biochemistry, University Medical Centre Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
- Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), Göttingen, Germany
| | - Claudia Höbartner
- Institute of Organic Chemistry, Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Katherine E Bohnsack
- Department of Molecular Biology, University Medical Centre Göttingen, Humboldtallee 23, 37073, Göttingen, Germany.
| | - Markus T Bohnsack
- Department of Molecular Biology, University Medical Centre Göttingen, Humboldtallee 23, 37073, Göttingen, Germany.
- Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), Göttingen, Germany.
- Göttingen Center for Molecular Biosciences, Georg-August University Göttingen, Justus-von-Liebig-Weg 11, Göttingen, 37077, Germany.
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6
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Motorin Y, Helm M. RNA nucleotide methylation: 2021 update. WILEY INTERDISCIPLINARY REVIEWS. RNA 2022; 13:e1691. [PMID: 34913259 DOI: 10.1002/wrna.1691] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Revised: 07/22/2021] [Accepted: 07/22/2021] [Indexed: 12/14/2022]
Abstract
Among RNA modifications, transfer of methylgroups from the typical cofactor S-adenosyl-l-methionine by methyltransferases (MTases) to RNA is by far the most common reaction. Since our last review about a decade ago, the field has witnessed the re-emergence of mRNA methylation as an important mechanism in gene regulation. Attention has then spread to many other RNA species; all being included into the newly coined concept of the "epitranscriptome." The focus moved from prokaryotes and single cell eukaryotes as model organisms to higher eukaryotes, in particular to mammals. The perception of the field has dramatically changed over the past decade. A previous lack of phenotypes in knockouts in single cell organisms has been replaced by the apparition of MTases in numerous disease models and clinical investigations. Major driving forces of the field include methylation mapping techniques, as well as the characterization of the various MTases, termed "writers." The latter term has spilled over from DNA modification in the neighboring epigenetics field, along with the designations "readers," applied to mediators of biological effects upon specific binding to a methylated RNA. Furthermore "eraser" enzymes effect the newly discovered oxidative removal of methylgroups. A sense of reversibility and dynamics has replaced the older perception of RNA modification as a concrete-cast, irreversible part of RNA maturation. A related concept concerns incompletely methylated residues, which, through permutation of each site, lead to inhomogeneous populations of numerous modivariants. This review recapitulates the major developments of the past decade outlined above, and attempts a prediction of upcoming trends. This article is categorized under: RNA Processing > RNA Editing and Modification.
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Affiliation(s)
- Yuri Motorin
- Université de Lorraine, CNRS, INSERM, UMS2008/US40 IBSLor, EpiRNA-Seq Core Facility, Nancy, France.,Université de Lorraine, CNRS, UMR7365 IMoPA, Nancy, France
| | - Mark Helm
- Institute of Pharmaceutical and Biomedical Sciences, Johannes Gutenberg-Universität, Mainz, Germany
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7
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Danchin A, Sekowska A, You C. One-carbon metabolism, folate, zinc and translation. Microb Biotechnol 2020; 13:899-925. [PMID: 32153134 PMCID: PMC7264889 DOI: 10.1111/1751-7915.13550] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Accepted: 02/17/2020] [Indexed: 12/16/2022] Open
Abstract
The translation process, central to life, is tightly connected to the one-carbon (1-C) metabolism via a plethora of macromolecule modifications and specific effectors. Using manual genome annotations and putting together a variety of experimental studies, we explore here the possible reasons of this critical interaction, likely to have originated during the earliest steps of the birth of the first cells. Methionine, S-adenosylmethionine and tetrahydrofolate dominate this interaction. Yet, 1-C metabolism is unlikely to be a simple frozen accident of primaeval conditions. Reactive 1-C species (ROCS) are buffered by the translation machinery in a way tightly associated with the metabolism of iron-sulfur clusters, zinc and potassium availability, possibly coupling carbon metabolism to nitrogen metabolism. In this process, the highly modified position 34 of tRNA molecules plays a critical role. Overall, this metabolic integration may serve both as a protection against the deleterious formation of excess carbon under various growth transitions or environmental unbalanced conditions and as a regulator of zinc homeostasis, while regulating input of prosthetic groups into nascent proteins. This knowledge should be taken into account in metabolic engineering.
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Affiliation(s)
- Antoine Danchin
- AMAbiotics SASInstitut Cochin24 rue du Faubourg Saint‐Jacques75014ParisFrance
- School of Biomedical SciencesLi Ka Shing Faculty of MedicineThe University of Hong KongS.A.R. Hong KongChina
| | - Agnieszka Sekowska
- AMAbiotics SASInstitut Cochin24 rue du Faubourg Saint‐Jacques75014ParisFrance
| | - Conghui You
- Shenzhen Key Laboratory of Microbial Genetic EngineeringCollege of Life Sciences and OceanologyShenzhen University1066 Xueyuan Rd518055ShenzhenChina
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8
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Hirata A, Okada K, Yoshii K, Shiraishi H, Saijo S, Yonezawa K, Shimizu N, Hori H. Structure of tRNA methyltransferase complex of Trm7 and Trm734 reveals a novel binding interface for tRNA recognition. Nucleic Acids Res 2020; 47:10942-10955. [PMID: 31586407 PMCID: PMC6847430 DOI: 10.1093/nar/gkz856] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 09/20/2019] [Accepted: 10/02/2019] [Indexed: 12/18/2022] Open
Abstract
The complex between Trm7 and Trm734 (Trm7–Trm734) from Saccharomyces cerevisiae catalyzes 2′-O-methylation at position 34 in tRNA. We report biochemical and structural studies of the Trm7–Trm734 complex. Purified recombinant Trm7–Trm734 preferentially methylates tRNAPhe transcript variants possessing two of three factors (Cm32, m1G37 and pyrimidine34). Therefore, tRNAPhe, tRNATrp and tRNALeu are specifically methylated by Trm7–Trm734. We have solved the crystal structures of the apo and S-adenosyl-L-methionine bound forms of Trm7–Trm734. Small angle X-ray scattering reveals that Trm7–Trm734 exists as a hetero-dimer in solution. Trm7 possesses a Rossmann-fold catalytic domain, while Trm734 consists of three WD40 β-propeller domains (termed BPA, BPB and BPC). BPA and BPC form a unique V-shaped cleft, which docks to Trm7. The C-terminal region of Trm7 is required for binding to Trm734. The D-arm of substrate tRNA is required for methylation by Trm7–Trm734. If the D-arm in tRNAPhe is docked onto the positively charged area of BPB in Trm734, the anticodon-loop is located near the catalytic pocket of Trm7. This model suggests that Trm734 is required for correct positioning of tRNA for methylation. Additionally, a point-mutation in Trm7, which is observed in FTSJ1 (human Trm7 ortholog) of nosyndromic X-linked intellectual disability patients, decreases the methylation activity.
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Affiliation(s)
- Akira Hirata
- Department of Materials Science and Biotechnology, Graduate school of Science and Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
| | - Keisuke Okada
- Department of Materials Science and Biotechnology, Graduate school of Science and Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
| | - Kazuaki Yoshii
- Department of Materials Science and Biotechnology, Graduate school of Science and Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
| | - Hiroyuki Shiraishi
- Department of Materials Science and Biotechnology, Graduate school of Science and Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
| | - Shinya Saijo
- Photon Factory, Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - Kento Yonezawa
- Photon Factory, Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - Nobutaka Shimizu
- Photon Factory, Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - Hiroyuki Hori
- Department of Materials Science and Biotechnology, Graduate school of Science and Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
- To whom correspondence should be addressed. Tel: +81 89 927 8548; Fax: +81 89 927 9941;
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9
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Barraud P, Tisné C. To be or not to be modified: Miscellaneous aspects influencing nucleotide modifications in tRNAs. IUBMB Life 2019; 71:1126-1140. [PMID: 30932315 PMCID: PMC6850298 DOI: 10.1002/iub.2041] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Accepted: 03/10/2019] [Indexed: 12/12/2022]
Abstract
Transfer RNAs (tRNAs) are essential components of the cellular protein synthesis machineries, but are also implicated in many roles outside translation. To become functional, tRNAs, initially transcribed as longer precursor tRNAs, undergo a tightly controlled biogenesis process comprising the maturation of their extremities, removal of intronic sequences if present, addition of the 3'-CCA amino-acid accepting sequence, and aminoacylation. In addition, the most impressive feature of tRNA biogenesis consists in the incorporation of a large number of posttranscriptional chemical modifications along its sequence. The chemical nature of these modifications is highly diverse, with more than hundred different modifications identified in tRNAs to date. All functions of tRNAs in cells are controlled and modulated by modifications, making the understanding of the mechanisms that determine and influence nucleotide modifications in tRNAs an essential point in tRNA biology. This review describes the different aspects that determine whether a certain position in a tRNA molecule is modified or not. We describe how sequence and structural determinants, as well as the presence of prior modifications control modification processes. We also describe how environmental factors and cellular stresses influence the level and/or the nature of certain modifications introduced in tRNAs, and report situations where these dynamic modulations of tRNA modification levels are regulated by active demodification processes. © 2019 IUBMB Life, 71(8):1126-1140, 2019.
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Affiliation(s)
- Pierre Barraud
- Expression génétique microbienneInstitut de biologie physico‐chimique (IBPC), UMR 8261, CNRS, Université Paris DiderotParisFrance
| | - Carine Tisné
- Expression génétique microbienneInstitut de biologie physico‐chimique (IBPC), UMR 8261, CNRS, Université Paris DiderotParisFrance
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10
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Hori H. Regulatory Factors for tRNA Modifications in Extreme- Thermophilic Bacterium Thermus thermophilus. Front Genet 2019; 10:204. [PMID: 30906314 PMCID: PMC6418473 DOI: 10.3389/fgene.2019.00204] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Accepted: 02/26/2019] [Indexed: 01/02/2023] Open
Abstract
Thermus thermophilus is an extreme-thermophilic bacterium that can grow at a wide range of temperatures (50-83°C). To enable T. thermophilus to grow at high temperatures, several biomolecules including tRNA and tRNA modification enzymes show extreme heat-resistance. Therefore, the modified nucleosides in tRNA from T. thermophilus have been studied mainly from the view point of tRNA stabilization at high temperatures. Such studies have shown that several modifications stabilize the structure of tRNA and are essential for survival of the organism at high temperatures. Together with tRNA modification enzymes, the modified nucleosides form a network that regulates the extent of different tRNA modifications at various temperatures. In this review, I describe this network, as well as the tRNA recognition mechanism of individual tRNA modification enzymes. Furthermore, I summarize the roles of other tRNA stabilization factors such as polyamines and metal ions.
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Affiliation(s)
- Hiroyuki Hori
- Department of Materials Sciences and Biotechnology, Graduate School of Science and Engineering, Ehime University, Matsuyama, Japan
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11
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RNA Modifications Modulate Activation of Innate Toll-Like Receptors. Genes (Basel) 2019; 10:genes10020092. [PMID: 30699960 PMCID: PMC6410116 DOI: 10.3390/genes10020092] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 01/23/2019] [Accepted: 01/25/2019] [Indexed: 12/13/2022] Open
Abstract
Self/foreign discrimination by the innate immune system depends on receptors that identify molecular patterns as associated to pathogens. Among others, this group includes endosomal Toll-like receptors, among which Toll-like receptors (TLR) 3, 7, 8, and 13 recognize and discriminate mammalian from microbial, potentially pathogen-associated, RNA. One of the discriminatory principles is the recognition of endogenous RNA modifications. Previous work has identified a couple of RNA modifications that impede activation of TLR signaling when incorporated in synthetic RNA molecules. Of note, work that is more recent has now shown that RNA modifications in their naturally occurring context can have immune-modulatory functions: Gm, a naturally occurring ribose-methylation within tRNA resulted in a lack of TLR7 stimulation and within a defined sequence context acted as antagonist. Additional RNA modifications with immune-modulatory functions have now been identified and recent work also indicates that RNA modifications within the context of whole prokaryotic or eukaryotic cells are indeed used for immune-modulation. This review will discuss new findings and developments in the field of immune-modulatory RNA modifications.
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12
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Krishnamohan A, Jackman JE. A Family Divided: Distinct Structural and Mechanistic Features of the SpoU-TrmD (SPOUT) Methyltransferase Superfamily. Biochemistry 2018; 58:336-345. [PMID: 30457841 DOI: 10.1021/acs.biochem.8b01047] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The SPOUT family of enzymes makes up the second largest of seven structurally distinct groups of methyltransferases and is named after two evolutionarily related RNA methyltransferases, SpoU and TrmD. A deep trefoil knotted domain in the tertiary structures of member enzymes defines the SPOUT family. For many years, formation of a homodimeric quaternary structure was thought to be a strict requirement for all SPOUT enzymes, critical for substrate binding and formation of the active site. However, recent structural characterization of two SPOUT members, Trm10 and Sfm1, revealed that they function as monomers without the requirement of this critical dimerization. This unusual monomeric form implies that these enzymes must exhibit a nontraditional substrate binding mode and active site architecture and may represent a new division in the SPOUT family with distinct properties removed from the dimeric enzymes. Here we discuss the mechanistic features of SPOUT enzymes with an emphasis on the monomeric members and implications of this "novel" monomeric structure on cofactor and substrate binding.
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Affiliation(s)
- Aiswarya Krishnamohan
- The Ohio State Biochemistry Program, Center for RNA Biology, and Department of Chemistry and Biochemistry , The Ohio State University , Columbus , Ohio 43210 , United States
| | - Jane E Jackman
- The Ohio State Biochemistry Program, Center for RNA Biology, and Department of Chemistry and Biochemistry , The Ohio State University , Columbus , Ohio 43210 , United States
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13
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Hori H, Kawamura T, Awai T, Ochi A, Yamagami R, Tomikawa C, Hirata A. Transfer RNA Modification Enzymes from Thermophiles and Their Modified Nucleosides in tRNA. Microorganisms 2018; 6:E110. [PMID: 30347855 PMCID: PMC6313347 DOI: 10.3390/microorganisms6040110] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 10/17/2018] [Accepted: 10/17/2018] [Indexed: 12/11/2022] Open
Abstract
To date, numerous modified nucleosides in tRNA as well as tRNA modification enzymes have been identified not only in thermophiles but also in mesophiles. Because most modified nucleosides in tRNA from thermophiles are common to those in tRNA from mesophiles, they are considered to work essentially in steps of protein synthesis at high temperatures. At high temperatures, the structure of unmodified tRNA will be disrupted. Therefore, thermophiles must possess strategies to stabilize tRNA structures. To this end, several thermophile-specific modified nucleosides in tRNA have been identified. Other factors such as RNA-binding proteins and polyamines contribute to the stability of tRNA at high temperatures. Thermus thermophilus, which is an extreme-thermophilic eubacterium, can adapt its protein synthesis system in response to temperature changes via the network of modified nucleosides in tRNA and tRNA modification enzymes. Notably, tRNA modification enzymes from thermophiles are very stable. Therefore, they have been utilized for biochemical and structural studies. In the future, thermostable tRNA modification enzymes may be useful as biotechnology tools and may be utilized for medical science.
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Affiliation(s)
- Hiroyuki Hori
- Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, Bunkyo 3, Matsuyama, Ehime 790-8577, Japan.
| | - Takuya Kawamura
- Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, Bunkyo 3, Matsuyama, Ehime 790-8577, Japan.
| | - Takako Awai
- Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, Bunkyo 3, Matsuyama, Ehime 790-8577, Japan.
| | - Anna Ochi
- Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, Bunkyo 3, Matsuyama, Ehime 790-8577, Japan.
| | - Ryota Yamagami
- Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, Bunkyo 3, Matsuyama, Ehime 790-8577, Japan.
| | - Chie Tomikawa
- Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, Bunkyo 3, Matsuyama, Ehime 790-8577, Japan.
| | - Akira Hirata
- Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, Bunkyo 3, Matsuyama, Ehime 790-8577, Japan.
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14
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McKenney KM, Rubio MAT, Alfonzo JD. Binding synergy as an essential step for tRNA editing and modification enzyme codependence in Trypanosoma brucei. RNA (NEW YORK, N.Y.) 2018; 24:56-66. [PMID: 29042505 PMCID: PMC5733570 DOI: 10.1261/rna.062893.117] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 10/02/2017] [Indexed: 05/10/2023]
Abstract
Transfer RNAs acquire a variety of naturally occurring chemical modifications during their maturation; these fine-tune their structure and decoding properties in a manner critical for protein synthesis. We recently reported that in the eukaryotic parasite, Trypanosoma brucei, a methylation and deamination event are unexpectedly interconnected, whereby the tRNA adenosine deaminase (TbADAT2/3) and the 3-methylcytosine methyltransferase (TbTrm140) strictly rely on each other for activity, leading to formation of m3C and m3U at position 32 in several tRNAs. Still however, it is not clear why these two enzymes, which work independently in other systems, are strictly codependent in T. brucei Here, we show that these enzymes exhibit binding synergism, or a mutual increase in binding affinity, that is more than the sum of the parts, when added together in a reaction. Although these enzymes interact directly with each other, tRNA binding assays using enzyme variants mutated in critical binding and catalytic sites indicate that the observed binding synergy stems from contributions from tRNA-binding domains distal to their active sites. These results provide a rationale for the known interactions of these proteins, while also speaking to the modulation of substrate specificity between seemingly unrelated enzymes. This information should be of value in furthering our understanding of how tRNA modification enzymes act together to regulate gene expression at the post-transcriptional level and provide a basis for the interdependence of such activities.
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Affiliation(s)
- Katherine M McKenney
- Department of Microbiology, Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210, USA
- Ohio State Biochemistry Program, The Ohio State University, Columbus, Ohio 43210, USA
| | - Mary Anne T Rubio
- Department of Microbiology, Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210, USA
| | - Juan D Alfonzo
- Department of Microbiology, Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210, USA
- Ohio State Biochemistry Program, The Ohio State University, Columbus, Ohio 43210, USA
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15
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Tomikawa C, Takai K, Hori H. Kinetic characterization of substrate-binding sites of thermostable tRNA methyltransferase (TrmB). J Biochem 2017; 163:133-142. [DOI: 10.1093/jb/mvx068] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 09/01/2017] [Indexed: 11/13/2022] Open
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16
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Transfer RNA methyltransferases with a SpoU-TrmD (SPOUT) fold and their modified nucleosides in tRNA. Biomolecules 2017; 7:biom7010023. [PMID: 28264529 PMCID: PMC5372735 DOI: 10.3390/biom7010023] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2017] [Accepted: 02/23/2017] [Indexed: 11/22/2022] Open
Abstract
The existence of SpoU-TrmD (SPOUT) RNA methyltransferase superfamily was first predicted by bioinformatics. SpoU is the previous name of TrmH, which catalyzes the 2’-O-methylation of ribose of G18 in tRNA; TrmD catalyzes the formation of N1-methylguanosine at position 37 in tRNA. Although SpoU (TrmH) and TrmD were originally considered to be unrelated, the bioinformatics study suggested that they might share a common evolution origin and form a single superfamily. The common feature of SPOUT RNA methyltransferases is the formation of a deep trefoil knot in the catalytic domain. In the past decade, the SPOUT RNA methyltransferase superfamily has grown; furthermore, knowledge concerning the functions of their modified nucleosides in tRNA has also increased. Some enzymes are potential targets in the design of anti-bacterial drugs. In humans, defects in some genes may be related to carcinogenesis. In this review, recent findings on the tRNA methyltransferases with a SPOUT fold and their methylated nucleosides in tRNA, including classification of tRNA methyltransferases with a SPOUT fold; knot structures, domain arrangements, subunit structures and reaction mechanisms; tRNA recognition mechanisms, and functions of modified nucleosides synthesized by this superfamily, are summarized. Lastly, the future perspective for studies on tRNA modification enzymes are considered.
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17
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Jackson SE, Suma A, Micheletti C. How to fold intricately: using theory and experiments to unravel the properties of knotted proteins. Curr Opin Struct Biol 2016; 42:6-14. [PMID: 27794211 DOI: 10.1016/j.sbi.2016.10.002] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 09/06/2016] [Accepted: 10/03/2016] [Indexed: 11/15/2022]
Abstract
Over the years, advances in experimental and computational methods have helped us to understand the role of thermodynamic, kinetic and active (chaperone-aided) effects in coordinating the folding steps required to achieving a knotted native state. Here, we review such developments by paying particular attention to the complementarity of experimental and computational studies. Key open issues that could be tackled with either or both approaches are finally pointed out.
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Affiliation(s)
- Sophie E Jackson
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom.
| | - Antonio Suma
- SISSA, International School for Advanced Studies, via Bonomea 265, I-34136 Trieste, Italy
| | - Cristian Micheletti
- SISSA, International School for Advanced Studies, via Bonomea 265, I-34136 Trieste, Italy.
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18
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Christian T, Sakaguchi R, Perlinska AP, Lahoud G, Ito T, Taylor EA, Yokoyama S, Sulkowska JI, Hou YM. Methyl transfer by substrate signaling from a knotted protein fold. Nat Struct Mol Biol 2016; 23:941-948. [PMID: 27571175 PMCID: PMC5429141 DOI: 10.1038/nsmb.3282] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Accepted: 07/27/2016] [Indexed: 12/13/2022]
Abstract
Proteins with knotted configurations, in comparison with unknotted proteins, are restricted in conformational space. Little is known regarding whether knotted proteins have sufficient dynamics to communicate between spatially separated substrate-binding sites. TrmD is a bacterial methyltransferase that uses a knotted protein fold to catalyze methyl transfer from S-adenosyl methionine (AdoMet) to G37-tRNA. The product, m1G37-tRNA, is essential for life and maintains protein-synthesis reading frames. Using an integrated approach of structural, kinetic, and computational analysis, we show that the structurally constrained TrmD knot is required for its catalytic activity. Unexpectedly, the TrmD knot undergoes complex internal movements that respond to AdoMet binding and signaling. Most of the signaling propagates the free energy of AdoMet binding, thereby stabilizing tRNA binding and allowing assembly of the active site. This work demonstrates new principles of knots as organized structures that capture the free energies of substrate binding and facilitate catalysis.
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Affiliation(s)
- Thomas Christian
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Reiko Sakaguchi
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Agata P Perlinska
- Center of New Technologies, University of Warsaw, Warsaw, Poland
- Inter-Faculty Individual Studies in Mathematics and Natural Sciences, University of Warsaw, Warsaw, Poland
| | - Georges Lahoud
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Takuhiro Ito
- RIKEN Systems and Structural Biology Center, Yokohama, Japan
- Graduate School of Science, University of Tokyo, Tokyo, Japan
- RIKEN Center for Life Science Technologies, Yokohama, Japan
| | - Erika A Taylor
- Department of Chemistry, Wesleyan University, Middletown, Connecticut, USA
| | - Shigeyuki Yokoyama
- RIKEN Systems and Structural Biology Center, Yokohama, Japan
- Graduate School of Science, University of Tokyo, Tokyo, Japan
- RIKEN Structural Biology Laboratory, Yokohama, Japan
| | - Joanna I Sulkowska
- Center of New Technologies, University of Warsaw, Warsaw, Poland
- Department of Chemistry, University of Warsaw, Warsaw, Poland
| | - Ya-Ming Hou
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
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19
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Rana AK, Ankri S. Reviving the RNA World: An Insight into the Appearance of RNA Methyltransferases. Front Genet 2016; 7:99. [PMID: 27375676 PMCID: PMC4893491 DOI: 10.3389/fgene.2016.00099] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 05/23/2016] [Indexed: 12/13/2022] Open
Abstract
RNA, the earliest genetic and catalytic molecule, has a relatively delicate and labile chemical structure, when compared to DNA. It is prone to be damaged by alkali, heat, nucleases, or stress conditions. One mechanism to protect RNA or DNA from damage is through site-specific methylation. Here, we propose that RNA methylation began prior to DNA methylation in the early forms of life evolving on Earth. In this article, the biochemical properties of some RNA methyltransferases (MTases), such as 2′-O-MTases (Rlml/RlmN), spOUT MTases and the NSun2 MTases are dissected for the insight they provide on the transition from an RNA world to our present RNA/DNA/protein world.
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Affiliation(s)
- Ajay K Rana
- Division of Biology, State Forensic Science Laboratory, Ministry of Home Affairs, Government of Jharkhand Ranchi, India
| | - Serge Ankri
- Department of Molecular Microbiology, The Ruth and Bruce Rappaport Faculty of Medicine, Technion Israel Institute of Technology Haifa, Israel
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20
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Zhou M, Long T, Fang ZP, Zhou XL, Liu RJ, Wang ED. Identification of determinants for tRNA substrate recognition by Escherichia coli C/U34 2'-O-methyltransferase. RNA Biol 2016; 12:900-11. [PMID: 26106808 PMCID: PMC4615657 DOI: 10.1080/15476286.2015.1050576] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Post-transcriptional modifications bring chemical diversity to tRNAs, especially at positions 34 and 37 of the anticodon stem-loop (ASL). TrmL is the prokaryotic methyltransferase that catalyzes the transfer of the methyl group from S-adenosyl-L-methionine to the wobble base of tRNALeuCAA and tRNALeuUAA isoacceptors. This Cm34/Um34 modification affects codon-anticodon interactions and is essential for translational fidelity. TrmL-catalyzed 2′-O-methylation requires its homodimerization; however, understanding of the tRNA recognition mechanism by TrmL remains elusive. In the current study, by measuring tRNA methylation by TrmL and performing kinetic analysis of tRNA mutants, we found that TrmL exhibits a fine-tuned tRNA substrate recognition mechanism. Anticodon stem-loop minihelices with an extension of 2 base pairs are the minimal substrate for EcTrmL methylation. A35 is a key residue for TrmL recognition, while A36-A37-A38 are important either via direct interaction with TrmL or due to the necessity for prior isopentenylation (i6) at A37. In addition, TrmL only methylates pyrimidines but not purine residues at the wobble position, and the 2′-O-methylation relies on prior N6-isopentenyladenosine modification at position 37.
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Affiliation(s)
- Mi Zhou
- a State Key Laboratory of Molecular Biology ; Institute of Biochemistry and Cell Biology; Shanghai Institutes for Biological Sciences ; Chinese Academy of Sciences ; Shanghai , PR China
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21
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Yamagami R, Tomikawa C, Shigi N, Kazayama A, Asai SI, Takuma H, Hirata A, Fourmy D, Asahara H, Watanabe K, Yoshizawa S, Hori H. Folate-/FAD-dependent tRNA methyltransferase from Thermus thermophilus regulates other modifications in tRNA at low temperatures. Genes Cells 2016; 21:740-54. [PMID: 27238446 DOI: 10.1111/gtc.12376] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 04/19/2016] [Indexed: 11/29/2022]
Abstract
TrmFO is a N(5) , N(10) -methylenetetrahydrofolate (CH2 THF)-/FAD-dependent tRNA methyltransferase, which synthesizes 5-methyluridine at position 54 (m(5) U54) in tRNA. Thermus thermophilus is an extreme-thermophilic eubacterium, which grows in a wide range of temperatures (50-83 °C). In T. thermophilus, modified nucleosides in tRNA and modification enzymes form a network, in which one modification regulates the degrees of other modifications and controls the flexibility of tRNA. To clarify the role of m(5) U54 and TrmFO in the network, we constructed the trmFO gene disruptant (∆trmFO) strain of T. thermophilus. Although this strain did not show any growth retardation at 70 °C, it showed a slow-growth phenotype at 50 °C. Nucleoside analysis showed increase in 2'-O-methylguanosine at position 18 and decrease in N(1) -methyladenosine at position 58 in the tRNA mixture from the ∆trmFO strain at 50 °C. These in vivo results were reproduced by in vitro experiments with purified enzymes. Thus, we concluded that the m(5) U54 modification have effects on the other modifications in tRNA through the network at 50 °C. (35) S incorporations into proteins showed that the protein synthesis activity of ∆trmFO strain was inferior to the wild-type strain at 50 °C, suggesting that the growth delay at 50 °C was caused by the inferior protein synthesis activity.
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Affiliation(s)
- Ryota Yamagami
- Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime, 790-8577, Japan
| | - Chie Tomikawa
- Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime, 790-8577, Japan
| | - Naoki Shigi
- Biotechnology Research Institute for Drug Discovery, National Institute of Advanced Industrial Science and Technology (AIST), 2-4-7 Aomi, Koto-ku, Tokyo, 135-0064, Japan
| | - Ai Kazayama
- Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime, 790-8577, Japan
| | - Shin-Ichi Asai
- Japan Biological Information Research Center (JBIRC), Japan Biological Informatics Consortium (JBIC), Tokyo, 135-0064, Japan
| | - Hiroyuki Takuma
- Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime, 790-8577, Japan
| | - Akira Hirata
- Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime, 790-8577, Japan
| | - Dominique Fourmy
- Institute for Integrative Biology of the Cell (I2BC), UMR9198, CEA, CNRS, Université Paris-Sud, 1 Avenue de la Terrasse, Gif-sur-Yvette, Cedex, 91198, France
| | - Haruichi Asahara
- New England Biolabs, Inc, 240 County Road, Ipswich, MA, 01938, USA
| | - Kimitsuna Watanabe
- Biomedicinal Information Research Center (BIRC), National Institute of Advanced Industrial Science and Technology (AIST), 2-4-7 Aomi, Koto-ku, Tokyo, 135-0064, Japan
| | - Satoko Yoshizawa
- Institute for Integrative Biology of the Cell (I2BC), UMR9198, CEA, CNRS, Université Paris-Sud, 1 Avenue de la Terrasse, Gif-sur-Yvette, Cedex, 91198, France
| | - Hiroyuki Hori
- Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime, 790-8577, Japan
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22
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Abstract
tRNA molecules undergo extensive post-transcriptional processing to generate the mature functional tRNA species that are essential for translation in all organisms. These processing steps include the introduction of numerous specific chemical modifications to nucleotide bases and sugars; among these modifications, methylation reactions are by far the most abundant. The tRNA methyltransferases comprise a diverse enzyme superfamily, including members of multiple structural classes that appear to have arisen independently during evolution. Even among closely related family members, examples of unusual substrate specificity and chemistry have been observed. Here we review recent advances in tRNA methyltransferase mechanism and function with a particular emphasis on discoveries of alternative substrate specificities and chemistry associated with some methyltransferases. Although the molecular function for a specific tRNA methylation may not always be clear, mutations in tRNA methyltransferases have been increasingly associated with human disease. The impact of tRNA methylation on human biology is also discussed.
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Affiliation(s)
- William E Swinehart
- a Center for RNA Biology and Department of Chemistry and Biochemistry ; Ohio State University ; Columbus , OH USA
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23
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Hori H, Terui Y, Nakamoto C, Iwashita C, Ochi A, Watanabe K, Oshima T. Effects of polyamines from Thermus thermophilus, an extreme-thermophilic eubacterium, on tRNA methylation by tRNA (Gm18) methyltransferase (TrmH). J Biochem 2015; 159:509-17. [PMID: 26721905 DOI: 10.1093/jb/mvv130] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 11/05/2015] [Indexed: 12/13/2022] Open
Abstract
Thermus thermophilus is an extreme-thermophilic eubacterium, which grows at a wide range of temperatures (50-83°C). This thermophile produces various polyamines including long and branched polyamines. In tRNAs from T. thermophilus, three distinct modifications, 2'-O-methylguanosine at position 18 (Gm18), 5-methyl-2-thiouridine at position 54 and N(1)-methyladenosine at position 58, are assembled at the elbow region to stabilize the L-shaped tRNA structure. However, the structures of unmodified tRNA precursors are disrupted at high temperatures. We hypothesize that polyamine(s) might have a positive effect on the modification process of unmodified tRNA transcript. We investigated the effects of eight polyamines on Gm18 formation in the yeast tRNA(Phe) transcript by tRNA (Gm18) methyltransferase (TrmH). Higher concentrations of linear polyamines inhibited TrmH activity at 55°C, while optimum concentration increased TrmH activity at 45-75°C. Exceptionally, caldohexamine, a long polyamine, did not show any positive effect on the TrmH activity at 55°C. However, temperature-dependent experiments revealed that 1 mM caldohexamine increased TrmH activity at 60-80°C. Furthermore, 0.25 mM tetrakis(3-aminopropy)ammonium, a branched polyamine, increased TrmH activity at a broad range of temperatures (40-85°C). Thus, caldohexamine and tetrakis(3-aminopropy)ammonium were found to enhance the TrmH activity at high temperatures.
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Affiliation(s)
- Hiroyuki Hori
- Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime 790-8577;
| | - Yusuke Terui
- Faculty of Pharmacy, Chiba Institute of Science, 15-8 Shiomi-cho, Choshi, Chiba; and
| | - Chisato Nakamoto
- Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime 790-8577
| | - Chikako Iwashita
- Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime 790-8577
| | - Anna Ochi
- Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime 790-8577
| | - Kazunori Watanabe
- Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime 790-8577
| | - Tairo Oshima
- Institute of Environmental Microbiology, Kyowa Kako Co. Ltd., Tadao 2-15-5, Machida 194-0035, Japan
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24
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Liu RJ, Long T, Zhou M, Zhou XL, Wang ED. tRNA recognition by a bacterial tRNA Xm32 modification enzyme from the SPOUT methyltransferase superfamily. Nucleic Acids Res 2015. [PMID: 26202969 PMCID: PMC4551947 DOI: 10.1093/nar/gkv745] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
TrmJ proteins from the SPOUT methyltransferase superfamily are tRNA Xm32 modification enzymes that occur in bacteria and archaea. Unlike archaeal TrmJ, bacterial TrmJ require full-length tRNA molecules as substrates. It remains unknown how bacterial TrmJs recognize substrate tRNAs and specifically catalyze a 2′-O modification at ribose 32. Herein, we demonstrate that all six Escherichia coli (Ec) tRNAs with 2′-O-methylated nucleosides at position 32 are substrates of EcTrmJ, and we show that the elbow region of tRNA, but not the amino acid acceptor stem, is needed for the methylation reaction. Our crystallographic study reveals that full-length EcTrmJ forms an unusual dimer in the asymmetric unit, with both the catalytic SPOUT domain and C-terminal extension forming separate dimeric associations. Based on these findings, we used electrophoretic mobility shift assay, isothermal titration calorimetry and enzymatic methods to identify amino acids within EcTrmJ that are involved in tRNA binding. We found that tRNA recognition by EcTrmJ involves the cooperative influences of conserved residues from both the SPOUT and extensional domains, and that this process is regulated by the flexible hinge region that connects these two domains.
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Affiliation(s)
- Ru-Juan Liu
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, The Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China University of Chinese Academy of Sciences, Beijing 100039, China
| | - Tao Long
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, The Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China University of Chinese Academy of Sciences, Beijing 100039, China
| | - Mi Zhou
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, The Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China University of Chinese Academy of Sciences, Beijing 100039, China
| | - Xiao-Long Zhou
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, The Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China University of Chinese Academy of Sciences, Beijing 100039, China
| | - En-Duo Wang
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, The Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China University of Chinese Academy of Sciences, Beijing 100039, China School of Life Science and Technology, ShanghaiTech University, 319 Yue Yang Road, Shanghai 200031, China
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25
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Takuma H, Ushio N, Minoji M, Kazayama A, Shigi N, Hirata A, Tomikawa C, Ochi A, Hori H. Substrate tRNA recognition mechanism of eubacterial tRNA (m1A58) methyltransferase (TrmI). J Biol Chem 2015; 290:5912-25. [PMID: 25593312 DOI: 10.1074/jbc.m114.606038] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
TrmI generates N(1)-methyladenosine at position 58 (m(1)A58) in tRNA. The Thermus thermophilus tRNA(Phe) transcript was methylated efficiently by T. thermophilus TrmI, whereas the yeast tRNA(Phe) transcript was poorly methylated. Fourteen chimeric tRNA transcripts derived from these two tRNAs revealed that TrmI recognized the combination of aminoacyl stem, variable region, and T-loop. This was confirmed by 10 deletion tRNA variants: TrmI methylated transcripts containing the aminoacyl stem, variable region, and T-arm. The requirement for the T-stem itself was confirmed by disrupting the T-stem. Disrupting the interaction between T- and D-arms accelerated the methylation, suggesting that this disruption is included in part of the reaction. Experiments with 17 point mutant transcripts elucidated the positive sequence determinants C56, purine 57, A58, and U60. Replacing A58 with inosine and 2-aminopurine completely abrogated methylation, demonstrating that the 6-amino group in A58 is recognized by TrmI. T. thermophilus tRNAGGU(Thr)GGU(Thr) contains C60 instead of U60. The tRNAGGU(Thr) transcript was poorly methylated by TrmI, and replacing C60 with U increased the methylation, consistent with the point mutation experiments. A gel shift assay revealed that tRNAGGU(Thr) had a low affinity for TrmI than tRNA(Phe). Furthermore, analysis of tRNAGGU(Thr) purified from the trmI gene disruptant strain revealed that the other modifications in tRNA accelerated the formation of m(1)A58 by TrmI. Moreover, nucleoside analysis of tRNAGGU(Thr) from the wild-type strain indicated that less than 50% of tRNAGG(Thr) contained m(1)A58. Thus, the results from the in vitro experiments were confirmed by the in vivo methylation patterns.
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Affiliation(s)
- Hiroyuki Takuma
- From the Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, Bunkyo 3, Matsuyama, Ehime 790-8577, Japan and
| | - Natsumi Ushio
- From the Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, Bunkyo 3, Matsuyama, Ehime 790-8577, Japan and
| | - Masayuki Minoji
- From the Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, Bunkyo 3, Matsuyama, Ehime 790-8577, Japan and
| | - Ai Kazayama
- From the Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, Bunkyo 3, Matsuyama, Ehime 790-8577, Japan and
| | - Naoki Shigi
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 2-4-7 Aomi, Koto-ku, Tokyo 135-0064, Japan
| | - Akira Hirata
- From the Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, Bunkyo 3, Matsuyama, Ehime 790-8577, Japan and
| | - Chie Tomikawa
- From the Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, Bunkyo 3, Matsuyama, Ehime 790-8577, Japan and
| | - Anna Ochi
- From the Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, Bunkyo 3, Matsuyama, Ehime 790-8577, Japan and
| | - Hiroyuki Hori
- From the Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, Bunkyo 3, Matsuyama, Ehime 790-8577, Japan and
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26
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A divalent metal ion-dependent N(1)-methyl transfer to G37-tRNA. ACTA ACUST UNITED AC 2014; 21:1351-1360. [PMID: 25219964 DOI: 10.1016/j.chembiol.2014.07.023] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Revised: 07/20/2014] [Accepted: 07/22/2014] [Indexed: 01/09/2023]
Abstract
The catalytic mechanism of the majority of S-adenosyl methionine (AdoMet)-dependent methyl transferases requires no divalent metal ions. Here we report that methyl transfer from AdoMet to N(1) of G37-tRNA, catalyzed by the bacterial TrmD enzyme, is strongly dependent on divalent metal ions and that Mg(2+) is the most physiologically relevant. Kinetic isotope analysis, metal rescue, and spectroscopic measurements indicate that Mg(2+) is not involved in substrate binding, but in promoting methyl transfer. On the basis of the pH-activity profile indicating one proton transfer during the TrmD reaction, we propose a catalytic mechanism in which the role of Mg(2+) is to help to increase the nucleophilicity of N(1) of G37 and stabilize the negative developing charge on O(6) during attack on the methyl sulfonium of AdoMet. This work demonstrates how Mg(2+) contributes to the catalysis of AdoMet-dependent methyl transfer in one of the most crucial posttranscriptional modifications to tRNA.
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27
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Somme J, Van Laer B, Roovers M, Steyaert J, Versées W, Droogmans L. Characterization of two homologous 2'-O-methyltransferases showing different specificities for their tRNA substrates. RNA (NEW YORK, N.Y.) 2014; 20:1257-71. [PMID: 24951554 PMCID: PMC4105751 DOI: 10.1261/rna.044503.114] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Accepted: 05/08/2014] [Indexed: 05/18/2023]
Abstract
The 2'-O-methylation of the nucleoside at position 32 of tRNA is found in organisms belonging to the three domains of life. Unrelated enzymes catalyzing this modification in Bacteria (TrmJ) and Eukarya (Trm7) have already been identified, but until now, no information is available for the archaeal enzyme. In this work we have identified the methyltransferase of the archaeon Sulfolobus acidocaldarius responsible for the 2'-O-methylation at position 32. This enzyme is a homolog of the bacterial TrmJ. Remarkably, both enzymes have different specificities for the nature of the nucleoside at position 32. While the four canonical nucleosides are substrates of the Escherichia coli enzyme, the archaeal TrmJ can only methylate the ribose of a cytidine. Moreover, the two enzymes recognize their tRNA substrates in a different way. We have solved the crystal structure of the catalytic domain of both enzymes to gain better understanding of these differences at a molecular level.
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Affiliation(s)
- Jonathan Somme
- Laboratoire de Microbiologie, Université libre de Bruxelles (ULB), 6041 Gosselies, Belgium
| | - Bart Van Laer
- Structural Biology Brussels, Vrije Universiteit Brussel, 1050 Brussels, Belgium Structural Biology Research Center, VIB, 1050 Brussels, Belgium
| | - Martine Roovers
- Institut de Recherches Microbiologiques Jean-Marie Wiame, B-1070 Bruxelles, Belgium
| | - Jan Steyaert
- Structural Biology Brussels, Vrije Universiteit Brussel, 1050 Brussels, Belgium Structural Biology Research Center, VIB, 1050 Brussels, Belgium
| | - Wim Versées
- Structural Biology Brussels, Vrije Universiteit Brussel, 1050 Brussels, Belgium Structural Biology Research Center, VIB, 1050 Brussels, Belgium
| | - Louis Droogmans
- Laboratoire de Microbiologie, Université libre de Bruxelles (ULB), 6041 Gosselies, Belgium
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28
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Subramanian M, Srinivasan T, Sudarsanam D. Examining the Gm18 and m(1)G Modification Positions in tRNA Sequences. Genomics Inform 2014; 12:71-5. [PMID: 25031570 PMCID: PMC4099351 DOI: 10.5808/gi.2014.12.2.71] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2013] [Revised: 03/20/2014] [Accepted: 03/26/2014] [Indexed: 12/30/2022] Open
Abstract
The tRNA structure contains conserved modifications that are responsible for its stability and are involved in the initiation and accuracy of the translation process. tRNA modification enzymes are prevalent in bacteria, archaea, and eukaryotes. tRNA Gm18 methyltransferase (TrmH) and tRNA m1G37 methyltransferase (TrmD) are prevalent and essential enzymes in bacterial populations. TrmH involves itself in methylation process at the 2'-OH group of ribose at the 18th position of guanosine (G) in tRNAs. TrmD methylates the G residue next to the anticodon in selected tRNA subsets. Initially, m1G37 modification was reported to take place on three conserved tRNA subsets (tRNAArg, tRNALeu, tRNAPro); later on, few archaea and eukaryotes organisms revealed that other tRNAs also have the m1G37 modification. The present study reveals Gm18, m1G37 modification, and positions of m1G that take place next to the anticodon in tRNA sequences. We selected extremophile organisms and attempted to retrieve the m1G and Gm18 modification bases in tRNA sequences. Results showed that the Gm18 modification G residue occurs in all tRNA subsets except three tRNAs (tRNAMet, tRNAPro, tRNAVal). Whereas the m1G37 modification base G is formed only on tRNAArg, tRNALeu, tRNAPro, and tRNAHis, the rest of the tRNAs contain adenine (A) next to the anticodon. Thus, we hypothesize that Gm18 modification and m1G modification occur irrespective of a G residue in tRNAs.
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Affiliation(s)
- Mayavan Subramanian
- Synthetic Biology and Biofuel Group, International Center for Genetic Engineering and Biotechnology (ICGEB), New Delhi 110 067, India
| | - Thangavelu Srinivasan
- DST-FIST Bioinformatics and Principal Investigator, School of Genomics and Bioinformatics, Department of Advanced Zoology and Biotechnology, Loyola College, Chennai 600 034, India
| | - Dorairaj Sudarsanam
- DST-FIST Bioinformatics and Principal Investigator, School of Genomics and Bioinformatics, Department of Advanced Zoology and Biotechnology, Loyola College, Chennai 600 034, India
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29
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Hori H. Methylated nucleosides in tRNA and tRNA methyltransferases. Front Genet 2014; 5:144. [PMID: 24904644 PMCID: PMC4033218 DOI: 10.3389/fgene.2014.00144] [Citation(s) in RCA: 141] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Accepted: 05/04/2014] [Indexed: 12/26/2022] Open
Abstract
To date, more than 90 modified nucleosides have been found in tRNA and the biosynthetic pathways of the majority of tRNA modifications include a methylation step(s). Recent studies of the biosynthetic pathways have demonstrated that the availability of methyl group donors for the methylation in tRNA is important for correct and efficient protein synthesis. In this review, I focus on the methylated nucleosides and tRNA methyltransferases. The primary functions of tRNA methylations are linked to the different steps of protein synthesis, such as the stabilization of tRNA structure, reinforcement of the codon-anticodon interaction, regulation of wobble base pairing, and prevention of frameshift errors. However, beyond these basic functions, recent studies have demonstrated that tRNA methylations are also involved in the RNA quality control system and regulation of tRNA localization in the cell. In a thermophilic eubacterium, tRNA modifications and the modification enzymes form a network that responses to temperature changes. Furthermore, several modifications are involved in genetic diseases, infections, and the immune response. Moreover, structural, biochemical, and bioinformatics studies of tRNA methyltransferases have been clarifying the details of tRNA methyltransferases and have enabled these enzymes to be classified. In the final section, the evolution of modification enzymes is discussed.
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Affiliation(s)
- Hiroyuki Hori
- Department of Materials Science and Biotechnology, Applied Chemistry, Graduate School of Science and Engineering, Ehime University Matsuyama, Japan
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