1
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Cao C, Zhang W, Gao Y, Yang J, Liu H, Gan J. High-resolution crystal structure of RNA kinase ArK1 from G. acetivorans. Biochem Biophys Res Commun 2024; 714:149966. [PMID: 38657448 DOI: 10.1016/j.bbrc.2024.149966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Revised: 04/17/2024] [Accepted: 04/17/2024] [Indexed: 04/26/2024]
Abstract
U47 phosphorylation (Up47) is a novel tRNA modification discovered recently; it can confer thermal stability and nuclease resistance to tRNAs. U47 phosphorylation is catalyzed by Archaeal RNA kinase (Ark1) in an ATP-dependent manner. However, the structural basis for tRNA and/or ATP binding by Ark1 is unclear. Here, we report the expression, purification, and crystallization studies of Ark1 from G. acetivorans (GaArk1). In addition to the Apo-form structure, one GaArk1-ATP complex was also determined in atomic resolution and revealed the detailed basis for ATP binding by GaArk1. The GaArk1-ATP complex represents the only ATP-bound structure of the Ark1 protein. The majority of the ATP-binding residues are conserved, suggesting that GaArk1 and the homologous proteins share similar mechanism in ATP binding. Sequence and structural analysis further indicated that endogenous guanosine will only inhibit the activities of certain Ark1 proteins, such as Ark1 from T. kodakarensis.
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Affiliation(s)
- Chulei Cao
- Shanghai Sci-Tech Inno Center for Infection & Immunity, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, Department of Biochemistry and Biophysics, School of Life Sciences, Fudan University, Shanghai, 200438, PR China
| | - Weizhen Zhang
- Shanghai Sci-Tech Inno Center for Infection & Immunity, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, Department of Biochemistry and Biophysics, School of Life Sciences, Fudan University, Shanghai, 200438, PR China
| | - Yanqing Gao
- Shanghai Sci-Tech Inno Center for Infection & Immunity, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, Department of Biochemistry and Biophysics, School of Life Sciences, Fudan University, Shanghai, 200438, PR China
| | - Jie Yang
- Shanghai Sci-Tech Inno Center for Infection & Immunity, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, Department of Biochemistry and Biophysics, School of Life Sciences, Fudan University, Shanghai, 200438, PR China
| | - Hehua Liu
- Shanghai Sci-Tech Inno Center for Infection & Immunity, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, Department of Biochemistry and Biophysics, School of Life Sciences, Fudan University, Shanghai, 200438, PR China
| | - Jianhua Gan
- Shanghai Sci-Tech Inno Center for Infection & Immunity, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, Department of Biochemistry and Biophysics, School of Life Sciences, Fudan University, Shanghai, 200438, PR China.
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2
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Yared MJ, Marcelot A, Barraud P. Beyond the Anticodon: tRNA Core Modifications and Their Impact on Structure, Translation and Stress Adaptation. Genes (Basel) 2024; 15:374. [PMID: 38540433 PMCID: PMC10969862 DOI: 10.3390/genes15030374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 03/15/2024] [Accepted: 03/18/2024] [Indexed: 06/14/2024] Open
Abstract
Transfer RNAs (tRNAs) are heavily decorated with post-transcriptional chemical modifications. Approximately 100 different modifications have been identified in tRNAs, and each tRNA typically contains 5-15 modifications that are incorporated at specific sites along the tRNA sequence. These modifications may be classified into two groups according to their position in the three-dimensional tRNA structure, i.e., modifications in the tRNA core and modifications in the anticodon-loop (ACL) region. Since many modified nucleotides in the tRNA core are involved in the formation of tertiary interactions implicated in tRNA folding, these modifications are key to tRNA stability and resistance to RNA decay pathways. In comparison to the extensively studied ACL modifications, tRNA core modifications have generally received less attention, although they have been shown to play important roles beyond tRNA stability. Here, we review and place in perspective selected data on tRNA core modifications. We present their impact on tRNA structure and stability and report how these changes manifest themselves at the functional level in translation, fitness and stress adaptation.
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Affiliation(s)
| | | | - Pierre Barraud
- Expression Génétique Microbienne, Université Paris Cité, CNRS, Institut de Biologie Physico-Chimique, F-75005 Paris, France; (M.-J.Y.); (A.M.)
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3
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Ohira T, Suzuki T. Transfer RNA modifications and cellular thermotolerance. Mol Cell 2024; 84:94-106. [PMID: 38181765 DOI: 10.1016/j.molcel.2023.11.041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 11/27/2023] [Accepted: 11/30/2023] [Indexed: 01/07/2024]
Abstract
RNA molecules are modified post-transcriptionally to acquire their diverse functions. Transfer RNA (tRNA) has the widest variety and largest numbers of RNA modifications. tRNA modifications are pivotal for decoding the genetic code and stabilizing the tertiary structure of tRNA molecules. Alternation of tRNA modifications directly modulates the structure and function of tRNAs and regulates gene expression. Notably, thermophilic organisms exhibit characteristic tRNA modifications that are dynamically regulated in response to varying growth temperatures, thereby bolstering fitness in extreme environments. Here, we review the history and latest findings regarding the functions and biogenesis of several tRNA modifications that contribute to the cellular thermotolerance of thermophiles.
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Affiliation(s)
- Takayuki Ohira
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Tsutomu Suzuki
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
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4
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Biosynthesis and Degradation of Sulfur Modifications in tRNAs. Int J Mol Sci 2021; 22:ijms222111937. [PMID: 34769366 PMCID: PMC8584467 DOI: 10.3390/ijms222111937] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/30/2021] [Accepted: 11/01/2021] [Indexed: 12/23/2022] Open
Abstract
Various sulfur-containing biomolecules include iron–sulfur clusters that act as cofactors for enzymes, sulfur-containing vitamins such as thiamin, and sulfur-modified nucleosides in RNA, in addition to methionine and cysteine in proteins. Sulfur-containing nucleosides are post-transcriptionally introduced into tRNA molecules, where they ensure precise codon recognition or stabilization of tRNA structure, thereby maintaining cellular proteome integrity. Modulating sulfur modification controls the translation efficiency of specific groups of genes, allowing organisms to adapt to specific environments. The biosynthesis of tRNA sulfur nucleosides involves elaborate ‘sulfur trafficking systems’ within cellular sulfur metabolism and ‘modification enzymes’ that incorporate sulfur atoms into tRNA. This review provides an up-to-date overview of advances in our knowledge of the mechanisms involved. It covers the functions, biosynthesis, and biodegradation of sulfur-containing nucleosides as well as the reaction mechanisms of biosynthetic enzymes catalyzed by the iron–sulfur clusters, and identification of enzymes involved in the de-modification of sulfur atoms of RNA. The mechanistic similarity of these opposite reactions is discussed. Mutations in genes related to these pathways can cause human diseases (e.g., cancer, diabetes, and mitochondrial diseases), emphasizing the importance of these pathways.
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5
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Zheng YY, Wu Y, Begley TJ, Sheng J. Sulfur modification in natural RNA and therapeutic oligonucleotides. RSC Chem Biol 2021; 2:990-1003. [PMID: 34458821 PMCID: PMC8341892 DOI: 10.1039/d1cb00038a] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 04/22/2021] [Indexed: 11/21/2022] Open
Abstract
Sulfur modifications have been discovered on both DNA and RNA. Sulfur substitution of oxygen atoms at nucleobase or backbone locations in the nucleic acid framework led to a wide variety of sulfur-modified nucleosides and nucleotides. While the discovery, regulation and functions of DNA phosphorothioate (PS) modification, where one of the non-bridging oxygen atoms is replaced by sulfur on the DNA backbone, are important topics, this review focuses on the sulfur modification in natural cellular RNAs and therapeutic nucleic acids. The sulfur modifications on RNAs exhibit diversity in terms of modification location and cellular function, but the various sulfur modifications share common biosynthetic strategies across RNA species, cell types and domains of life. The first section reviews the post-transcriptional sulfur modifications on nucleobases with an emphasis on thiouridine on tRNA and phosphorothioate modification on RNA backbones, as well as the functions of the sulfur modifications on different species of cellular RNAs. The second section reviews the biosynthesis of different types of sulfur modifications and summarizes the general strategy for the biosynthesis of sulfur-containing RNA residues. One of the main goals of investigating sulfur modifications is to aid the genomic drug development pipeline and enhance our understandings of the rapidly growing nucleic acid-based gene therapies. The last section of the review focuses on the current drug development strategies employing sulfur substitution of oxygen atoms in therapeutic RNAs.
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Affiliation(s)
- Ya Ying Zheng
- Department of Chemistry, University at Albany, State University of New York 1400 Washington Ave. Albany NY 12222 USA
- The RNA Institute, University at Albany, State University of New York 1400 Washington Ave. Albany NY 12222 USA
| | - Ying Wu
- Department of Chemistry, University at Albany, State University of New York 1400 Washington Ave. Albany NY 12222 USA
- The RNA Institute, University at Albany, State University of New York 1400 Washington Ave. Albany NY 12222 USA
| | - Thomas J Begley
- The RNA Institute, University at Albany, State University of New York 1400 Washington Ave. Albany NY 12222 USA
- Department of Biological Science, University at Albany, State University of New York 1400 Washington Ave. Albany NY 12222 USA
| | - Jia Sheng
- Department of Chemistry, University at Albany, State University of New York 1400 Washington Ave. Albany NY 12222 USA
- The RNA Institute, University at Albany, State University of New York 1400 Washington Ave. Albany NY 12222 USA
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6
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Rose S, Auxilien S, Havelund JF, Kirpekar F, Huber H, Grosjean H, Douthwaite S. The hyperthermophilic partners Nanoarchaeum and Ignicoccus stabilize their tRNA T-loops via different but structurally equivalent modifications. Nucleic Acids Res 2020; 48:6906-6918. [PMID: 32459340 PMCID: PMC7337903 DOI: 10.1093/nar/gkaa411] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Revised: 04/19/2020] [Accepted: 05/06/2020] [Indexed: 01/31/2023] Open
Abstract
The universal L-shaped tertiary structure of tRNAs is maintained with the help of nucleotide modifications within the D- and T-loops, and these modifications are most extensive within hyperthermophilic species. The obligate-commensal Nanoarchaeum equitans and its phylogenetically-distinct host Ignicoccus hospitalis grow physically coupled under identical hyperthermic conditions. We report here two fundamentally different routes by which these archaea modify the key conserved nucleotide U54 within their tRNA T-loops. In N. equitans, this nucleotide is methylated by the S-adenosylmethionine-dependent enzyme NEQ053 to form m5U54, and a recombinant version of this enzyme maintains specificity for U54 in Escherichia coli. In N. equitans, m5U54 is subsequently thiolated to form m5s2U54. In contrast, I. hospitalis isomerizes U54 to pseudouridine prior to methylating its N1-position and thiolating the O4-position of the nucleobase to form the previously uncharacterized nucleotide m1s4Ψ. The methyl and thiol groups in m1s4Ψ and m5s2U are presented within the T-loop in a spatially identical manner that stabilizes the 3′-endo-anti conformation of nucleotide-54, facilitating stacking onto adjacent nucleotides and reverse-Hoogsteen pairing with nucleotide m1A58. Thus, two distinct structurally-equivalent solutions have evolved independently and convergently to maintain the tertiary fold of tRNAs under extreme hyperthermic conditions.
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Affiliation(s)
- Simon Rose
- Department of Biochemistry & Molecular Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Sylvie Auxilien
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Jesper F Havelund
- Department of Biochemistry & Molecular Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Finn Kirpekar
- Department of Biochemistry & Molecular Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Harald Huber
- Lehrstuhl für Mikrobiologie und Archaeenzentrum, Universität Regensburg, Universitätsstraße 31, D-93053 Regensburg, Germany
| | - Henri Grosjean
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Stephen Douthwaite
- Department of Biochemistry & Molecular Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
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7
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Edwards AM, Addo MA, Dos Santos PC. Extracurricular Functions of tRNA Modifications in Microorganisms. Genes (Basel) 2020; 11:genes11080907. [PMID: 32784710 PMCID: PMC7466049 DOI: 10.3390/genes11080907] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 07/29/2020] [Accepted: 08/02/2020] [Indexed: 12/29/2022] Open
Abstract
Transfer RNAs (tRNAs) are essential adaptors that mediate translation of the genetic code. These molecules undergo a variety of post-transcriptional modifications, which expand their chemical reactivity while influencing their structure, stability, and functionality. Chemical modifications to tRNA ensure translational competency and promote cellular viability. Hence, the placement and prevalence of tRNA modifications affects the efficiency of aminoacyl tRNA synthetase (aaRS) reactions, interactions with the ribosome, and transient pairing with messenger RNA (mRNA). The synthesis and abundance of tRNA modifications respond directly and indirectly to a range of environmental and nutritional factors involved in the maintenance of metabolic homeostasis. The dynamic landscape of the tRNA epitranscriptome suggests a role for tRNA modifications as markers of cellular status and regulators of translational capacity. This review discusses the non-canonical roles that tRNA modifications play in central metabolic processes and how their levels are modulated in response to a range of cellular demands.
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8
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Archaeosine Modification of Archaeal tRNA: Role in Structural Stabilization. J Bacteriol 2020; 202:JB.00748-19. [PMID: 32041795 DOI: 10.1128/jb.00748-19] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 01/29/2020] [Indexed: 12/20/2022] Open
Abstract
Archaeosine (G+) is a structurally complex modified nucleoside found quasi-universally in the tRNA of Archaea and located at position 15 in the dihydrouridine loop, a site not modified in any tRNA outside the Archaea G+ is characterized by an unusual 7-deazaguanosine core structure with a formamidine group at the 7-position. The location of G+ at position 15, coupled with its novel molecular structure, led to a hypothesis that G+ stabilizes tRNA tertiary structure through several distinct mechanisms. To test whether G+ contributes to tRNA stability and define the biological role of G+, we investigated the consequences of introducing targeted mutations that disrupt the biosynthesis of G+ into the genome of the hyperthermophilic archaeon Thermococcus kodakarensis and the mesophilic archaeon Methanosarcina mazei, resulting in modification of the tRNA with the G+ precursor 7-cyano-7-deazaguansine (preQ0) (deletion of arcS) or no modification at position 15 (deletion of tgtA). Assays of tRNA stability from in vitro-prepared and enzymatically modified tRNA transcripts, as well as tRNA isolated from the T. kodakarensis mutant strains, demonstrate that G+ at position 15 imparts stability to tRNAs that varies depending on the overall modification state of the tRNA and the concentration of magnesium chloride and that when absent results in profound deficiencies in the thermophily of T. kodakarensis IMPORTANCE Archaeosine is ubiquitous in archaeal tRNA, where it is located at position 15. Based on its molecular structure, it was proposed to stabilize tRNA, and we show that loss of archaeosine in Thermococcus kodakarensis results in a strong temperature-sensitive phenotype, while there is no detectable phenotype when it is lost in Methanosarcina mazei Measurements of tRNA stability show that archaeosine stabilizes the tRNA structure but that this effect is much greater when it is present in otherwise unmodified tRNA transcripts than in the context of fully modified tRNA, suggesting that it may be especially important during the early stages of tRNA processing and maturation in thermophiles. Our results demonstrate how small changes in the stability of structural RNAs can be manifested in significant biological-fitness changes.
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9
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Shigi N, Horitani M, Miyauchi K, Suzuki T, Kuroki M. An ancient type of MnmA protein is an iron-sulfur cluster-dependent sulfurtransferase for tRNA anticodons. RNA (NEW YORK, N.Y.) 2020; 26:240-250. [PMID: 31801798 PMCID: PMC7025502 DOI: 10.1261/rna.072066.119] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Accepted: 12/01/2019] [Indexed: 05/27/2023]
Abstract
Transfer RNA (tRNA) is an adaptor molecule indispensable for assigning amino acids to codons on mRNA during protein synthesis. 2-thiouridine (s2U) derivatives in the anticodons (position 34) of tRNAs for glutamate, glutamine, and lysine are post-transcriptional modifications essential for precise and efficient codon recognition in all organisms. s2U34 is introduced either by (i) bacterial MnmA/eukaryote mitochondrial Mtu1 or (ii) eukaryote cytosolic Ncs6/archaeal NcsA, and the latter enzymes possess iron-sulfur (Fe-S) cluster. Here, we report the identification of novel-type MnmA homologs containing three conserved Cys residues, which could support Fe-S cluster binding and catalysis, in a broad range of bacteria, including thermophiles, Cyanobacteria, Mycobacteria, Actinomyces, Clostridium, and Helicobacter Using EPR spectroscopy, we revealed that Thermus thermophilus MnmA (TtMnmA) contains an oxygen-sensitive [4Fe-4S]-type cluster. Efficient in vitro formation of s2U34 in tRNALys and tRNAGln by holo-TtMnmA occurred only under anaerobic conditions. Mutational analysis of TtMnmA suggested that the Fe-S cluster is coordinated by the three conserved Cys residues (Cys105, Cys108, and Cys200), and is essential for its activity. Evolutionary scenarios for the sulfurtransferases, including the Fe-S cluster containing Ncs6/NcsA s2U thiouridylases and several distantly related sulfurtransferases, are proposed.
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Affiliation(s)
- 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
| | - Masaki Horitani
- Faculty of Agriculture, Department of Applied Biochemistry and Food Science, Saga University, 1 Honjo-machi, Saga 840-8502, Japan
| | - Kenjyo Miyauchi
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Tsutomu Suzuki
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Misao Kuroki
- 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
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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: 3.2] [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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7-Methylguanosine Modifications in Transfer RNA (tRNA). Int J Mol Sci 2018; 19:ijms19124080. [PMID: 30562954 PMCID: PMC6320965 DOI: 10.3390/ijms19124080] [Citation(s) in RCA: 129] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 12/05/2018] [Accepted: 12/13/2018] [Indexed: 01/15/2023] Open
Abstract
More than 90 different modified nucleosides have been identified in tRNA. Among the tRNA modifications, the 7-methylguanosine (m7G) modification is found widely in eubacteria, eukaryotes, and a few archaea. In most cases, the m7G modification occurs at position 46 in the variable region and is a product of tRNA (m7G46) methyltransferase. The m7G46 modification forms a tertiary base pair with C13-G22, and stabilizes the tRNA structure. A reaction mechanism for eubacterial tRNA m7G methyltransferase has been proposed based on the results of biochemical, bioinformatic, and structural studies. However, an experimentally determined mechanism of methyl-transfer remains to be ascertained. The physiological functions of m7G46 in tRNA have started to be determined over the past decade. For example, tRNA m7G46 or tRNA (m7G46) methyltransferase controls the amount of other tRNA modifications in thermophilic bacteria, contributes to the pathogenic infectivity, and is also associated with several diseases. In this review, information of tRNA m7G modifications and tRNA m7G methyltransferases is summarized and the differences in reaction mechanism between tRNA m7G methyltransferase and rRNA or mRNA m7G methylation enzyme are discussed.
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12
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Shigi N. Recent Advances in Our Understanding of the Biosynthesis of Sulfur Modifications in tRNAs. Front Microbiol 2018; 9:2679. [PMID: 30450093 PMCID: PMC6225789 DOI: 10.3389/fmicb.2018.02679] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2018] [Accepted: 10/19/2018] [Indexed: 12/30/2022] Open
Abstract
Sulfur is an essential element in all living organisms. In tRNA molecules, there are many sulfur-containing nucleosides, introduced post-transcriptionally, that function to ensure proper codon recognition or stabilization of tRNA structure, thereby enabling accurate and efficient translation. The biosynthesis of tRNA sulfur modifications involves unique sulfur trafficking systems that are closely related to cellular sulfur metabolism, and “modification enzymes” that incorporate sulfur atoms into tRNA. Herein, recent biochemical and structural characterization of the biosynthesis of sulfur modifications in tRNA is reviewed, with special emphasis on the reaction mechanisms of modification enzymes. It was recently revealed that TtuA/Ncs6-type 2-thiouridylases from thermophilic bacteria/archaea/eukaryotes are oxygen-sensitive iron-sulfur proteins that utilize a quite different mechanism from other 2-thiouridylase subtypes lacking iron-sulfur clusters such as bacterial MnmA. The various reaction mechanisms of RNA sulfurtransferases are also discussed, including tRNA methylthiotransferase MiaB (a radical S-adenosylmethionine-type iron-sulfur enzyme) and other sulfurtransferases involved in both primary and secondary sulfur-containing metabolites.
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Affiliation(s)
- Naoki Shigi
- Biotechnology Research Institute for Drug Discovery, National Institute of Advanced Industrial Science and Technology (AIST), Tokyo, Japan
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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: 4.8] [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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Aučynaitė A, Rutkienė R, Gasparavičiūtė R, Meškys R, Urbonavičius J. A gene encoding a DUF523 domain protein is involved in the conversion of 2-thiouracil into uracil. ENVIRONMENTAL MICROBIOLOGY REPORTS 2018; 10:49-56. [PMID: 29194984 DOI: 10.1111/1758-2229.12605] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 11/17/2017] [Accepted: 11/19/2017] [Indexed: 06/07/2023]
Abstract
Modified nucleotides are present in many RNA species in all Domains of Life. While the biosynthetic pathways of such nucleotides are well studied, much less is known about the degradation of RNAs and the return to the metabolism of modified nucleotides, their respective nucleosides or heterocyclic bases. Using an E. coli uracil auxotroph, we screened the metagenomic libraries for genes, which would allow the conversion of 2-thiouracil to uracil and thereby lead to the growth on a defined synthetic medium. We show that a gene encoding a protein consisting of previously uncharacterized Domain of Unknown Function 523 (DUF523) is responsible for such phenotype. We have purified this recombinant protein and demonstrated that it contains a FeS cluster. The substitution of cysteines, which have been predicted to form such clusters, with alanines abolished the growth phenotype. We conclude that DUF523 is involved in the conversion of 2-thiouracil into uracil in vivo.
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Affiliation(s)
- Agota Aučynaitė
- Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Rasa Rutkienė
- Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Renata Gasparavičiūtė
- Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Rolandas Meškys
- Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Jaunius Urbonavičius
- Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Life Sciences Center, Vilnius University, Vilnius, Lithuania
- Department of Chemistry and Bioengineering, Vilnius Gediminas Technical University, Vilnius, Lithuania
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15
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Prywes N, Michaels YS, Pal A, Oh SS, Szostak JW. Thiolated uridine substrates and templates improve the rate and fidelity of ribozyme-catalyzed RNA copying. Chem Commun (Camb) 2018; 52:6529-32. [PMID: 27109314 DOI: 10.1039/c6cc02692c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ribozyme-catalyzed RNA polymerization is inefficient and error prone. Here we demonstrate that two alternative bases, 2-thio-uridine (s(2)U) and 2-thio-ribo-thymidine (s(2)T), improve the rate and fidelity of ribozyme catalyzed nucleotide addition as NTP substrates and as template bases. We also demonstrate the functionality of s(2)U and s(2)T-containing ribozymes.
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Affiliation(s)
- Noam Prywes
- Howard Hughes Medical Institute, Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, Massachusetts 02114, USA and Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford St., Cambridge, Massachusetts 02138, USA
| | - Yale S Michaels
- Howard Hughes Medical Institute, Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, Massachusetts 02114, USA and Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 9DS, UK
| | - Ayan Pal
- Howard Hughes Medical Institute, Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, Massachusetts 02114, USA and Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, USA.
| | - Seung Soo Oh
- Howard Hughes Medical Institute, Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, Massachusetts 02114, USA and Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, USA.
| | - Jack W Szostak
- Howard Hughes Medical Institute, Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, Massachusetts 02114, USA and Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford St., Cambridge, Massachusetts 02138, USA and Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, USA.
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16
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Lorenz C, Lünse CE, Mörl M. tRNA Modifications: Impact on Structure and Thermal Adaptation. Biomolecules 2017; 7:E35. [PMID: 28375166 PMCID: PMC5485724 DOI: 10.3390/biom7020035] [Citation(s) in RCA: 216] [Impact Index Per Article: 30.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2017] [Revised: 03/27/2017] [Accepted: 03/28/2017] [Indexed: 12/27/2022] Open
Abstract
Transfer RNAs (tRNAs) are central players in translation, functioning as adapter molecules between the informational level of nucleic acids and the functional level of proteins. They show a highly conserved secondary and tertiary structure and the highest density of post-transcriptional modifications among all RNAs. These modifications concentrate in two hotspots-the anticodon loop and the tRNA core region, where the D- and T-loop interact with each other, stabilizing the overall structure of the molecule. These modifications can cause large rearrangements as well as local fine-tuning in the 3D structure of a tRNA. The highly conserved tRNA shape is crucial for the interaction with a variety of proteins and other RNA molecules, but also needs a certain flexibility for a correct interplay. In this context, it was shown that tRNA modifications are important for temperature adaptation in thermophilic as well as psychrophilic organisms, as they modulate rigidity and flexibility of the transcripts, respectively. Here, we give an overview on the impact of modifications on tRNA structure and their importance in thermal adaptation.
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Affiliation(s)
- Christian Lorenz
- Institute of Biochemistry, Leipzig University, Brüderstraße 34, 04103 Leipzig, Germany.
| | - Christina E Lünse
- Institute of Biochemistry, Leipzig University, Brüderstraße 34, 04103 Leipzig, Germany.
| | - Mario Mörl
- Institute of Biochemistry, Leipzig University, Brüderstraße 34, 04103 Leipzig, Germany.
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17
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Väre VYP, Eruysal ER, Narendran A, Sarachan KL, Agris PF. Chemical and Conformational Diversity of Modified Nucleosides Affects tRNA Structure and Function. Biomolecules 2017; 7:E29. [PMID: 28300792 PMCID: PMC5372741 DOI: 10.3390/biom7010029] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 03/06/2017] [Accepted: 03/06/2017] [Indexed: 12/21/2022] Open
Abstract
RNAs are central to all gene expression through the control of protein synthesis. Four major nucleosides, adenosine, guanosine, cytidine and uridine, compose RNAs and provide sequence variation, but are limited in contributions to structural variation as well as distinct chemical properties. The ability of RNAs to play multiple roles in cellular metabolism is made possible by extensive variation in length, conformational dynamics, and the over 100 post-transcriptional modifications. There are several reviews of the biochemical pathways leading to RNA modification, but the physicochemical nature of modified nucleosides and how they facilitate RNA function is of keen interest, particularly with regard to the contributions of modified nucleosides. Transfer RNAs (tRNAs) are the most extensively modified RNAs. The diversity of modifications provide versatility to the chemical and structural environments. The added chemistry, conformation and dynamics of modified nucleosides occurring at the termini of stems in tRNA's cloverleaf secondary structure affect the global three-dimensional conformation, produce unique recognition determinants for macromolecules to recognize tRNAs, and affect the accurate and efficient decoding ability of tRNAs. This review will discuss the impact of specific chemical moieties on the structure, stability, electrochemical properties, and function of tRNAs.
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Affiliation(s)
- Ville Y P Väre
- The RNA Institute, Departments of Biological Sciences and Chemistry, University at Albany, State University of New York, Albany, NY 12222, USA.
| | - Emily R Eruysal
- The RNA Institute, Departments of Biological Sciences and Chemistry, University at Albany, State University of New York, Albany, NY 12222, USA.
| | - Amithi Narendran
- The RNA Institute, Departments of Biological Sciences and Chemistry, University at Albany, State University of New York, Albany, NY 12222, USA.
| | - Kathryn L Sarachan
- The RNA Institute, Departments of Biological Sciences and Chemistry, University at Albany, State University of New York, Albany, NY 12222, USA.
| | - Paul F Agris
- The RNA Institute, Departments of Biological Sciences and Chemistry, University at Albany, State University of New York, Albany, NY 12222, USA.
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18
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Abstract
To date, about 90 post-transcriptional modifications have been reported in tRNA expanding their chemical and functional diversity. Methylation is the most frequent post-transcriptional tRNA modification that can occur on almost all nitrogen sites of the nucleobases, on the C5 atom of pyrimidines, on the C2 and C8 atoms of adenosine and, additionally, on the oxygen of the ribose 2′-OH. The methylation on the N1 atom of adenosine to form 1-methyladenosine (m1A) has been identified at nucleotide position 9, 14, 22, 57, and 58 in different tRNAs. In some cases, these modifications have been shown to increase tRNA structural stability and induce correct tRNA folding. This review provides an overview of the currently known m1A modifications, the different m1A modification sites, the biological role of each modification, and the enzyme responsible for each methylation in different species. The review further describes, in detail, two enzyme families responsible for formation of m1A at nucleotide position 9 and 58 in tRNA with a focus on the tRNA binding, m1A mechanism, protein domain organisation and overall structures.
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19
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Shigi N. Sulfur Modifications in tRNA: Function and Implications for Human Disease. MODIFIED NUCLEIC ACIDS IN BIOLOGY AND MEDICINE 2016. [DOI: 10.1007/978-3-319-34175-0_3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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20
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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: 1.6] [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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21
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Liu Y, Zhu Y, Teng M, Li X. Crystallographic analysis of RsmA, a ribosomal RNA small subunit methyltransferase A from Staphylococcus aureus. Acta Crystallogr F Struct Biol Commun 2015; 71:1063-6. [PMID: 26249700 PMCID: PMC4528942 DOI: 10.1107/s2053230x15011279] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Accepted: 06/09/2015] [Indexed: 11/11/2022] Open
Abstract
RsmA, a ribosomal RNA small subunit methyltransferase from Staphylococcus aureus, catalyzes the N(6) methylation of adenine in 16S rRNA. In this study, RsmA from Staphylococcus aureus was cloned, expressed, purified and crystallized. The crystal belonged to space group C2, with unit-cell parameters a = 84.38, b = 157.76, c = 96.50 Å, β = 95.04°. X-ray diffraction data were collected to a resolution of 3.2 Å. The self-rotation function and the Matthews coefficient suggested the presence of two molecules in the asymmetric unit.
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Affiliation(s)
- Yang Liu
- Hefei National Laboratory for Physical Sciences at Microscale, Innovation Center for Cell Signaling Network, School of Life Science, University of Science and Technology of China, Hefei, Anhui 230026, People’s Republic of China
- Key Laboratory of Structural Biology, Hefei Science Center of CAS, Chinese Academy of Science, Hefei, Anhui 230026, People’s Republic of China
| | - Yuwei Zhu
- Hefei National Laboratory for Physical Sciences at Microscale, Innovation Center for Cell Signaling Network, School of Life Science, University of Science and Technology of China, Hefei, Anhui 230026, People’s Republic of China
- Key Laboratory of Structural Biology, Hefei Science Center of CAS, Chinese Academy of Science, Hefei, Anhui 230026, People’s Republic of China
| | - Maikun Teng
- Hefei National Laboratory for Physical Sciences at Microscale, Innovation Center for Cell Signaling Network, School of Life Science, University of Science and Technology of China, Hefei, Anhui 230026, People’s Republic of China
- Key Laboratory of Structural Biology, Hefei Science Center of CAS, Chinese Academy of Science, Hefei, Anhui 230026, People’s Republic of China
| | - Xu Li
- Hefei National Laboratory for Physical Sciences at Microscale, Innovation Center for Cell Signaling Network, School of Life Science, University of Science and Technology of China, Hefei, Anhui 230026, People’s Republic of China
- Key Laboratory of Structural Biology, Hefei Science Center of CAS, Chinese Academy of Science, Hefei, Anhui 230026, People’s Republic of China
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22
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Dégut C, Ponchon L, Folly-Klan M, Barraud P, Tisné C. The m1A(58) modification in eubacterial tRNA: An overview of tRNA recognition and mechanism of catalysis by TrmI. Biophys Chem 2015; 210:27-34. [PMID: 26189113 DOI: 10.1016/j.bpc.2015.06.012] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Revised: 06/16/2015] [Accepted: 06/27/2015] [Indexed: 01/23/2023]
Abstract
The enzymes of the TrmI family catalyze the formation of the m(1)A58 modification in tRNA. We previously solved the crystal structure of the Thermus thermophilus enzyme and conducted a biophysical study to characterize the interaction between TrmI and tRNA. TrmI enzymes are active as a tetramer and up to two tRNAs can bind to TrmI simultaneously. In this paper, we present the structures of two TrmI mutants (D170A and Y78A). These residues are conserved in the active site of TrmIs and their mutations result in a dramatic alteration of TrmI activity. Both structures of TrmI mutants revealed the flexibility of the N-terminal domain that is probably important to bind tRNA. The structure of TrmI Y78A catalytic domain is unmodified regarding the binding of the SAM co-factor and the conformation of residues potentially interacting with the substrate adenine. This structure reinforces the previously proposed role of Y78, i.e. stabilize the conformation of the A58 ribose needed to hold the adenosine in the active site. The structure of the D170A mutant shows a flexible active site with one loop occupying in part the place of the co-factor and the second loop moving at the entrance to the active site. This structure and recent data confirms the central role of D170 residue binding the amino moiety of SAM and the exocyclic amino group of adenine. Possible mechanisms for methyl transfer are then discussed.
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Affiliation(s)
- Clément Dégut
- Laboratoire de Cristallographie et RMN biologiques, CNRS, Université Paris Descartes, Paris Sorbonne Cité, 4 avenue de l'Observatoire, 75006, Paris
| | - Luc Ponchon
- Laboratoire de Cristallographie et RMN biologiques, CNRS, Université Paris Descartes, Paris Sorbonne Cité, 4 avenue de l'Observatoire, 75006, Paris
| | - Marcia Folly-Klan
- Laboratoire de Cristallographie et RMN biologiques, CNRS, Université Paris Descartes, Paris Sorbonne Cité, 4 avenue de l'Observatoire, 75006, Paris
| | - Pierre Barraud
- Laboratoire de Cristallographie et RMN biologiques, CNRS, Université Paris Descartes, Paris Sorbonne Cité, 4 avenue de l'Observatoire, 75006, Paris
| | - Carine Tisné
- Laboratoire de Cristallographie et RMN biologiques, CNRS, Université Paris Descartes, Paris Sorbonne Cité, 4 avenue de l'Observatoire, 75006, Paris.
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23
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Chawla M, Oliva R, Bujnicki JM, Cavallo L. An atlas of RNA base pairs involving modified nucleobases with optimal geometries and accurate energies. Nucleic Acids Res 2015; 43:6714-29. [PMID: 26117545 PMCID: PMC4538814 DOI: 10.1093/nar/gkv606] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 05/28/2015] [Indexed: 01/08/2023] Open
Abstract
Posttranscriptional modifications greatly enhance the chemical information of RNA molecules, contributing to explain the diversity of their structures and functions. A significant fraction of RNA experimental structures available to date present modified nucleobases, with half of them being involved in H-bonding interactions with other bases, i.e. ‘modified base pairs’. Herein we present a systematic investigation of modified base pairs, in the context of experimental RNA structures. To this end, we first compiled an atlas of experimentally observed modified base pairs, for which we recorded occurrences and structural context. Then, for each base pair, we selected a representative for subsequent quantum mechanics calculations, to find out its optimal geometry and interaction energy. Our structural analyses show that most of the modified base pairs are non Watson–Crick like and are involved in RNA tertiary structure motifs. In addition, quantum mechanics calculations quantify and provide a rationale for the impact of the different modifications on the geometry and stability of the base pairs they participate in.
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Affiliation(s)
- Mohit Chawla
- King Abdullah University of Science and Technology (KAUST), Physical Sciences and Engineering Division, Kaust Catalysis Center, Thuwal 23955-6900, Saudi Arabia
| | - Romina Oliva
- Department of Sciences and Technologies, University Parthenope of Naples, Centro Direzionale Isola C4, I-80143, Naples, Italy
| | - Janusz M Bujnicki
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, ul. Ks. Trojdena 4, 02-109 Warsaw, Poland Laboratory of Bioinformatics, Institute of Molecular Biology and Biotechnology, Faculty of Biology, Adam Mickiewicz University, Umultowska 89, 61-614 Poznan, Poland
| | - Luigi Cavallo
- King Abdullah University of Science and Technology (KAUST), Physical Sciences and Engineering Division, Kaust Catalysis Center, Thuwal 23955-6900, Saudi Arabia
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24
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Kusuba H, Yoshida T, Iwasaki E, Awai T, Kazayama A, Hirata A, Tomikawa C, Yamagami R, Hori H. In vitrodihydrouridine formation by tRNA dihydrouridine synthase fromThermus thermophilus, an extreme-thermophilic eubacterium. J Biochem 2015; 158:513-21. [DOI: 10.1093/jb/mvv066] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Accepted: 05/30/2015] [Indexed: 01/08/2023] Open
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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: 2.9] [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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Kazayama A, Yamagami R, Yokogawa T, Hori H. Improved solid-phase DNA probe method for tRNA purification: large-scale preparation and alteration of DNA fixation. J Biochem 2015; 157:411-8. [DOI: 10.1093/jb/mvu089] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 12/02/2014] [Indexed: 11/12/2022] Open
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27
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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: 14.1] [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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28
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Shigi N. Biosynthesis and functions of sulfur modifications in tRNA. Front Genet 2014; 5:67. [PMID: 24765101 PMCID: PMC3980101 DOI: 10.3389/fgene.2014.00067] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Accepted: 03/17/2014] [Indexed: 12/19/2022] Open
Abstract
Sulfur is an essential element for a variety of cellular constituents in all living organisms. In tRNA molecules, there are many sulfur-containing nucleosides, such as the derivatives of 2-thiouridine (s2U), 4-thiouridine (s4U), 2-thiocytidine (s2C), and 2-methylthioadenosine (ms2A). Earlier studies established the functions of these modifications for accurate and efficient translation, including proper recognition of the codons in mRNA or stabilization of tRNA structure. In many cases, the biosynthesis of these sulfur modifications starts with cysteine desulfurases, which catalyze the generation of persulfide (an activated form of sulfur) from cysteine. Many sulfur-carrier proteins are responsible for delivering this activated sulfur to each biosynthesis pathway. Finally, specific “modification enzymes” activate target tRNAs and then incorporate sulfur atoms. Intriguingly, the biosynthesis of 2-thiouridine in all domains of life is functionally and evolutionarily related to the ubiquitin-like post-translational modification system of cellular proteins in eukaryotes. This review summarizes the recent characterization of the biosynthesis of sulfur modifications in tRNA and the novel roles of this modification in cellular functions in various model organisms, with a special emphasis on 2-thiouridine derivatives. Each biosynthesis pathway of sulfur-containing molecules is mutually modulated via sulfur trafficking, and 2-thiouridine and codon usage bias have been proposed to control the translation of specific genes.
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Affiliation(s)
- Naoki Shigi
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology Tokyo, Japan
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29
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Baldridge KC, Contreras LM. Functional implications of ribosomal RNA methylation in response to environmental stress. Crit Rev Biochem Mol Biol 2013; 49:69-89. [PMID: 24261569 DOI: 10.3109/10409238.2013.859229] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The study of post-transcriptional RNA modifications has long been focused on the roles these chemical modifications play in maintaining ribosomal function. The field of ribosomal RNA modification has reached a milestone in recent years with the confirmation of the final unknown ribosomal RNA methyltransferase in Escherichia coli in 2012. Furthermore, the last 10 years have brought numerous discoveries in non-coding RNAs and the roles that post-transcriptional modification play in their functions. These observations indicate the need for a revitalization of this field of research to understand the role modifications play in maintaining cellular health in a dynamic environment. With the advent of high-throughput sequencing technologies, the time is ripe for leaps and bounds forward. This review discusses ribosomal RNA methyltransferases and their role in responding to external stress in Escherichia coli, with a specific focus on knockout studies and on analysis of transcriptome data with respect to rRNA methyltransferases.
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Affiliation(s)
- Kevin C Baldridge
- McKetta Department of Chemical Engineering, The University of Texas at Austin , Austin, TX , USA
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30
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Nakagawa H, Kuratani M, Goto-Ito S, Ito T, Katsura K, Terada T, Shirouzu M, Sekine SI, Shigi N, Yokoyama S. Crystallographic and mutational studies on the tRNA thiouridine synthetase TtuA. Proteins 2013; 81:1232-44. [DOI: 10.1002/prot.24273] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Revised: 02/06/2013] [Accepted: 02/07/2013] [Indexed: 11/09/2022]
Affiliation(s)
| | - Mitsuo Kuratani
- RIKEN Systems and Structural Biology Center; 1-7-22 Suehiro-cho; Tsurumi; Yokohama 230-0045; Japan
| | | | | | - Kazushige Katsura
- RIKEN Systems and Structural Biology Center; 1-7-22 Suehiro-cho; Tsurumi; Yokohama 230-0045; Japan
| | - Takaho Terada
- RIKEN Systems and Structural Biology Center; 1-7-22 Suehiro-cho; Tsurumi; Yokohama 230-0045; Japan
| | - Mikako Shirouzu
- RIKEN Systems and Structural Biology Center; 1-7-22 Suehiro-cho; Tsurumi; Yokohama 230-0045; Japan
| | | | - Naoki Shigi
- Biomedicinal Information Research Center (BIRC); National Institute of Advanced Industrial Science and Technology (AIST); 2-4-7 Aomi, Koto-ku; Tokyo 135-0064; Japan
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31
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El Yacoubi B, Bailly M, de Crécy-Lagard V. Biosynthesis and Function of Posttranscriptional Modifications of Transfer RNAs. Annu Rev Genet 2012; 46:69-95. [DOI: 10.1146/annurev-genet-110711-155641] [Citation(s) in RCA: 380] [Impact Index Per Article: 31.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Basma El Yacoubi
- Department of Microbiology and Department of Microbiology and Cell Science, University of Florida, Gainesville, Florida 32611-0700;
| | - Marc Bailly
- Department of Microbiology and Department of Microbiology and Cell Science, University of Florida, Gainesville, Florida 32611-0700;
| | - Valérie de Crécy-Lagard
- Department of Microbiology and Department of Microbiology and Cell Science, University of Florida, Gainesville, Florida 32611-0700;
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32
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Motorin Y, Helm M. RNA nucleotide methylation. WILEY INTERDISCIPLINARY REVIEWS-RNA 2011; 2:611-31. [PMID: 21823225 DOI: 10.1002/wrna.79] [Citation(s) in RCA: 334] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Methylation of RNA occurs at a variety of atoms, nucleotides, sequences and tertiary structures. Strongly related to other posttranscriptional modifications, methylation of different RNA species includes tRNA, rRNA, mRNA, tmRNA, snRNA, snoRNA, miRNA, and viral RNA. Different catalytic strategies are employed for RNA methylation by a variety of RNA-methyltransferases which fall into four superfamilies. This review outlines the different functions of methyl groups in RNA, including biophysical, biochemical and metabolic stabilization of RNA, quality control, resistance to antibiotics, mRNA reading frame maintenance, deciphering of normal and altered genetic code, selenocysteine incorporation, tRNA aminoacylation, ribotoxins, splicing, intracellular trafficking, immune response, and others. Connections to other fields including gene regulation, DNA repair, stress response, and possibly histone acetylation and exocytosis are pointed out. WIREs RNA 2011 2 611-631 DOI: 10.1002/wrna.79 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Yuri Motorin
- Laboratoire ARN-RNP Maturation-Structure-Fonction, Enzymologie Moléculaire et Structurale (AREMS), Université Henri Poincaré, Vandoeuvre-les-Nancy, France
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Kawai G, Yokoyama S. Professor Tatsuo Miyazawa: from molecular structure to biological function. J Biochem 2011; 148:631-8. [PMID: 21127037 DOI: 10.1093/jb/mvq118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The late Prof. Tatsuo Miyazawa was an outstanding physical chemist, who established a number of spectroscopic methods to analyse the structures of proteins, peptides and nucleotides, and used them to understand molecular functions. He developed an infrared spectroscopic method to quantitatively analyse the secondary structures, α-helices and β-strands, of proteins. He successfully utilized nuclear magnetic resonance (NMR) methods to determine the conformations of peptides and proteins, particularly with respect to the interactions with their target molecules, which served as a solid basis for the wide range of applications of NMR spectroscopy to life science research. For example, he found that physiologically active peptides are randomly flexible in solution, but assume a particular effective conformation upon binding to their functional environments, such as membranes. He also used NMR spectroscopy to quantitatively analyse the conformer equilibrium of nucleotides, and related the dynamic properties of the modified nucleosides naturally-occurring in transfer ribonucleic acids (tRNAs) to their roles in correct codon recognition in protein synthesis. Furthermore, he studied the mechanisms of protein biosynthesis systems, including tRNA and aminoacyl-tRNA synthetases. Inspired by the structural mechanism of amino acid recognition by aminoacyl-tRNA synthetases, as revealed by NMR spectroscopy, he initiated a new research area in which non-natural amino acids are site-specifically incorporated into proteins to achieve novel protein functions (alloprotein technology).
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Affiliation(s)
- Gota Kawai
- Department of Life and Environmental Sciences, Chiba Institute of Technology, Chiba, Japan
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34
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Abstract
Post-transcriptional ribonucleotide modification is a phenomenon best studied in tRNA, where it occurs most frequently and in great chemical diversity. This paper reviews the intrinsic network of modifications in the structural core of the tRNA, which governs structural flexibility and rigidity to fine-tune the molecule to peak performance and to regulate its steady-state level. Structural effects of RNA modifications range from nanometer-scale rearrangements to subtle restrictions of conformational space on the angstrom scale. Structural stabilization resulting from nucleotide modification results in increased thermal stability and translates into protection against unspecific degradation by bases and nucleases. Several mechanisms of specific degradation of hypomodified tRNA, which were only recently discovered, provide a link between structural and metabolic stability.
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Affiliation(s)
- Yuri Motorin
- Laboratoire ARN-RNP Maturation-Structure-Fonction, Enzymologie Moléculaire et Structurale (AREMS), UMR 7214 CNRS-UHP Faculté des Sciences et Techniques, Université Henri Poincaré, Nancy 1, Bld des Aiguillettes, BP 70239, 54506 Vandoeuvre-les-Nancy, France
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35
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Matsushita I, Yanase H. The Genomic Structure of Thermus Bacteriophage IN93. J Biochem 2009; 146:775-85. [DOI: 10.1093/jb/mvp125] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
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36
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Shigi N, Sakaguchi Y, Suzuki T, Watanabe K. Identification of two tRNA thiolation genes required for cell growth at extremely high temperatures. J Biol Chem 2006; 281:14296-306. [PMID: 16547008 DOI: 10.1074/jbc.m511675200] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Thermostability of tRNA in thermophilic bacteria is effected by post-transcriptional modifications, such as 2-thioribothymidine (s2T) at position 54. Using a proteomics approach, we identified two genes (ttuA and ttuB; tRNA-two-thiouridine) that are essential for the synthesis of s2T in Thermus thermophilus. Mutation of either gene completely abolishes thio-modification of s2T, and these mutants exhibit a temperature-sensitive phenotype. These results suggest that bacterial growth at higher temperatures is achieved through the thermal stabilization of tRNA by a 2-thiolation modification. TtuA (TTC0106) is possibly an ATPase possessing a P-loop motif. TtuB (TTC0105) is a putative thio-carrier protein that exhibits significant sequence homology with ThiS of the thiamine synthesis pathway. Both TtuA and TtuB are required for in vitro s2T formation in the presence of cysteine and ATP. The addition of cysteine desulfurases such as IscS (TTC0087) or SufS (TTC1373) enhances the sulfur transfer reaction in vitro.
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Affiliation(s)
- Naoki Shigi
- Biological Information Research Center, National Institute of Advanced Industrial Science and Technology, 2-42 Aomi, Koto-ku, Tokyo 135-0064, Japan
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37
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Varshney U, Ramesh V, Madabushi A, Gaur R, Subramanya HS, RajBhandary UL. Mycobacterium tuberculosis Rv2118c codes for a single-component homotetrameric m1A58 tRNA methyltransferase. Nucleic Acids Res 2004; 32:1018-27. [PMID: 14960715 PMCID: PMC373377 DOI: 10.1093/nar/gkh207] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Modified nucleosides in tRNAs play important roles in tRNA structure, biosynthesis and function, and serve as crucial determinants of bacterial growth and virulence. In the yeast Saccharomyces cerevisiae, mutants defective in N1-methylation of a highly conserved adenosine (A58) in the TPsiC loop of initiator tRNA are non-viable. The yeast m1A58 methyltransferase is a heterotetramer consisting of two different polypeptide chains, Gcd14p and Gcd10p. Interestingly, while m1A58 is not found in most eubacteria, the mycobacterial tRNAs have m1A58. Here, we report on the cloning, overexpression, purification and biochemical characterization of the Rv2118c gene-encoded protein (Rv2118p) from Mycobacterium tuberculosis, which is homologous to yeast Gcd14p. We show that Rv2118c codes for a protein of approximately 31 kDa. Activity assays, modified base analysis and primer extension experiments using reverse transcriptase reveal that Rv2118p is an S-adenosyl-l-methionine-dependent methyltransferase which carries out m1A58 modification in tRNAs, both in vivo and in vitro. Remarkably, when expressed in Escherichia coli, the enzyme methylates the endogenous E.coli initiator tRNA essentially quantitatively. Furthermore, unlike its eukaryotic counterpart, which is a heterotetramer, the mycobacterial enzyme is a homotetramer. Also, the presence of rT modification at position 54, which was found to inhibit the Tetrahymena pyriformis enzyme, does not affect the activity of Rv2118p. Thus, the mycobacterial m1A58 tRNA methyltransferase possesses distinct biochemical properties. We discuss aspects of the biological relevance of Rv2118p in M.tuberculosis, and its potential use as a drug target to control the growth of mycobacteria.
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Affiliation(s)
- U Varshney
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
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38
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Noon KR, Guymon R, Crain PF, McCloskey JA, Thomm M, Lim J, Cavicchioli R. Influence of temperature on tRNA modification in archaea: Methanococcoides burtonii (optimum growth temperature [Topt], 23 degrees C) and Stetteria hydrogenophila (Topt, 95 degrees C). J Bacteriol 2003; 185:5483-90. [PMID: 12949100 PMCID: PMC193749 DOI: 10.1128/jb.185.18.5483-5490.2003] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2003] [Accepted: 07/03/2003] [Indexed: 11/20/2022] Open
Abstract
We report the first study of tRNA modification in psychrotolerant archaea, specifically in the archaeon Methanococcoides burtonii grown at 4 and 23 degrees C. For comparison, unfractionated tRNA from the archaeal hyperthermophile Stetteria hydrogenophila cultured at 93 degrees C was examined. Analysis of modified nucleosides using liquid chromatography-electrospray ionization mass spectrometry revealed striking differences in levels and identities of tRNA modifications between the two organisms. Although the modification levels in M. burtonii tRNA are the lowest in any organism of which we are aware, it contains more than one residue per tRNA molecule of dihydrouridine, a molecule associated with maintenance of polynucleotide flexibility at low temperatures. No differences in either identities or levels of modifications, including dihydrouridine, as a function of culture temperature were observed, in contrast to selected tRNA modifications previously reported for archaeal hyperthermophiles. By contrast, S. hydrogenophila tRNA was found to contain a remarkable structural diversity of 31 modified nucleosides, including nine methylated guanosines, with eight different nucleoside species methylated at O-2' of ribose, known to be an effective stabilizing motif in RNA. These results show that some aspects of tRNA modification in archaea are strongly associated with environmental temperature and support the thesis that posttranscriptional modification is a universal natural mechanism for control of RNA molecular structure that operates across a wide temperature range in archaea as well as bacteria.
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Affiliation(s)
- Kathleen R Noon
- Department of Medicinal Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
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39
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Ishitani R, Nureki O, Nameki N, Okada N, Nishimura S, Yokoyama S. Alternative tertiary structure of tRNA for recognition by a posttranscriptional modification enzyme. Cell 2003; 113:383-94. [PMID: 12732145 DOI: 10.1016/s0092-8674(03)00280-0] [Citation(s) in RCA: 142] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Transfer RNA (tRNA) canonically has the clover-leaf secondary structure with the acceptor, D, anticodon, and T arms, which are folded into the L-shaped tertiary structure. To strengthen the L form, posttranscriptional modifications occur on nucleotides buried within the core, but the modification enzymes are paradoxically inaccessible to them in the L form. In this study, we determined the crystal structure of tRNA bound with archaeosine tRNA-guanine transglycosylase, which modifies G15 of the D arm in the core. The bound tRNA assumes an alternative conformation ("lambda form") drastically different from the L form. All of the D-arm secondary base pairs and the canonical tertiary interactions are disrupted. Furthermore, a helical structure is reorganized, while the rest of the D arm is single stranded and protruded. Consequently, the enzyme precisely locates the exposed G15 in the active site, by counting the nucleotide number from G1 to G15 in the lambda form.
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MESH Headings
- Bacterial Proteins/chemistry
- Bacterial Proteins/metabolism
- Base Sequence
- Crystallography, X-Ray
- Models, Molecular
- Nucleic Acid Conformation
- Pentosyltransferases/chemistry
- Pentosyltransferases/metabolism
- Protein Binding
- Protein Conformation
- Pyrococcus/genetics
- RNA/chemistry
- RNA/genetics
- RNA/metabolism
- RNA Processing, Post-Transcriptional
- RNA, Bacterial/chemistry
- RNA, Bacterial/genetics
- RNA, Bacterial/metabolism
- RNA, Mitochondrial
- RNA, Transfer, Val/chemistry
- RNA, Transfer, Val/genetics
- RNA, Transfer, Val/metabolism
- Structure-Activity Relationship
- Substrate Specificity
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Affiliation(s)
- Ryuichiro Ishitani
- Department of Biophysics and Biochemistry, Graduate School of Science, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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40
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Droogmans L, Roovers M, Bujnicki JM, Tricot C, Hartsch T, Stalon V, Grosjean H. Cloning and characterization of tRNA (m1A58) methyltransferase (TrmI) from Thermus thermophilus HB27, a protein required for cell growth at extreme temperatures. Nucleic Acids Res 2003; 31:2148-56. [PMID: 12682365 PMCID: PMC153742 DOI: 10.1093/nar/gkg314] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
N1-methyladenosine (m1A) is found at position 58 in the T-loop of many tRNAs. In yeast, the formation of this modified nucleoside is catalyzed by the essential tRNA (m1A58) methyltransferase, a tetrameric enzyme that is composed of two types of subunits (Gcd14p and Gcd10p). In this report we describe the cloning, expression and characterization of a Gcd14p homolog from the hyperthermophilic bacterium Thermus thermophilus. The purified recombinant enzyme behaves as a homotetramer of 150 kDa by gel filtration and catalyzes the site- specific formation of m1A at position 58 of the T-loop of tRNA in the absence of any other complementary protein. S-adenosylmethionine is used as donor of the methyl group. Thus, we propose to name the bacterial enzyme TrmI and accordingly its structural gene trmI. These results provide a key evolutionary link between the functionally characterized two-component eukaryotic enzyme and the recently described crystal structure of an uncharacterized, putative homotetrameric methyltransferase Rv2118c from Mycobacterium tuberculosis. Interest ingly, inactivation of the T.thermophilus trmI gene results in a thermosensitive phenotype (growth defect at 80 degrees C), which suggests a role of the N1-methylation of tRNA adenosine-58 in adaptation of life to extreme temperatures.
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Affiliation(s)
- Louis Droogmans
- Laboratoire de Microbiologie, Université Libre de Bruxelles, Institut de Recherches Microbiologiques Jean-Marie Wiame, Avenue E. Gryson 1, B-1070 Bruxelles, Belgium
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41
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Hara-Yokoyama M, Yokoyama S, Watanabe T, Watanabe K, Kitazume M, Mitamura Y, Morii T, Takahashi S, Kuchino Y, Nishimura S, Miyazawa T. Characteristic anticodon sequences of major tRNA species from an extreme thermophile,Thermus thermophilusHB8. FEBS Lett 2001. [DOI: 10.1016/0014-5793(86)80667-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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42
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Abstract
Structure/function relationships accounting for specific tRNA charging by class II aspartyl-tRNA synthetases from Saccharomyces cerevisiae, Escherichia coli and Thermus thermophilus are reviewed. Effects directly linked to tRNA features are emphasized and aspects about synthetase contribution in expression of tRNA(Asp) identity are also covered. Major identity nucleotides conferring aspartate specificity to yeast, E coli and T thermophilus tRNAs comprise G34, U35, C36, C38 and G73, a set of nucleotides conserved in tRNA(Asp) molecules of other biological origin. Aspartate specificity can be enhanced by negative discrimination preventing, eg mischarging of native yeast tRNA(Asp by yeast arginyl-tRNA synthetase. In the yeast system crystallography shows that identity nucleotides are in contact with identity amino acids located in the catalytic and anticodon binding domains of the synthetase. Specificity of RNA/protein interaction involves a conformational change of the tRNA that optimizes the H-bonding potential of the identity signals on both partners of the complex. Mutation of identity nucleotides leads to decreased aspartylation efficiencies accompanied by a loss of specific H-bonds and an altered adaptation of tRNA on the synthetase. Species-specific characteristics of aspartate systems are the number, location and nature of minor identity signals. These features and the structural variations in aspartate tRNAs and synthetases are correlated with mechanistic differences in the aminoacylation reactions catalyzed by the various aspartyl-tRNA synthetases. The reality of the aspartate identity set is verified by its functional expression in a variety of RNA frameworks. Inversely a number of identities can be expressed within a tRNA(Asp) framework. From this emerged the concept of the RNA structural frameworks underlying expression of identities which is illustrated with data obtained with engineered tRNAs. Efficient aspartylation of minihelices is explained by the primordial role of G73. From this and other considerations it is suggested that aspartate identity appeared early in the history of tRNA aminoacylation systems.
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Affiliation(s)
- R Giegé
- Unité Structure des Macromolécules Biologioues et Mécanismes de Reconnaissance, Institut de Biologie Moléculaire et Cellulaire du CNRS, Strasbourg, France
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43
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Vysotskaya V, Tischenko S, Garber M, Kern D, Mougel M, Ehresmann C, Ehresmann B. The ribosomal protein S8 from Thermus thermophilus VK1. Sequencing of the gene, overexpression of the protein in Escherichia coli and interaction with rRNA. EUROPEAN JOURNAL OF BIOCHEMISTRY 1994; 223:437-45. [PMID: 7519982 DOI: 10.1111/j.1432-1033.1994.tb19011.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The gene of the ribosomal protein S8 from Thermus thermophilus VK1 has been isolated from a genomic library by hybridization of an oligonucleotide coding for the N-terminal amino acid sequence of the protein, amplified by PCR and sequenced. Nucleotide sequence reveals an open reading frame coding for a protein of 138 amino acid residues (M(r) 15,839). The codon usage shows that 94% of the codons possess G or C in the third position, and agrees with the preferential usage of codons of high G+C content in the bacteria of the genus Thermus. The amino acid sequence of the protein shows 48% identity with the protein from Escherichia coli. Ribosomal protein S8 from T. thermophilus has been expressed in E. coli under the control of the T7 promoter and purified to homogeneity by heat treatment of the extract followed by cation-exchange chromatography. Conditions were defined in which T. thermophilus protein S8 binds specifically an homologous 16S rRNA fragment containing the putative S8 binding site with an apparent association constant of 5 x 10(7) M-1. The overexpressed protein binds the rRNA with the same affinity as that extracted from T. thermophilus, indicating that the thermophilic protein is correctly folded in E. coli. The specificity of this binding is dependent on the ionic strength. The protein S8 from T. thermophilus recognizes the E. coli rRNA binding sites as efficiently as the S8 protein from E. coli. This result agrees with sequence comparisons of the S8 binding site on the small subunit rRNA from E. coli and from T. thermophilus, showing strong similarities in the regions involved in the interaction. It suggests that the structural features responsible for the recognition are conserved in the mesophilic and thermophilic eubacteria, despite structural peculiarities in the thermophilic partners conferring thermostability.
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MESH Headings
- Amino Acid Sequence
- Base Sequence
- Blotting, Southern
- Cloning, Molecular
- DNA, Bacterial/chemistry
- DNA, Bacterial/genetics
- DNA, Bacterial/isolation & purification
- Escherichia coli/genetics
- Escherichia coli/metabolism
- Gene Expression
- Genes, Bacterial
- Molecular Sequence Data
- Molecular Weight
- Nucleic Acid Hybridization
- Polymerase Chain Reaction
- Promoter Regions, Genetic
- Protein Binding
- Protein Structure, Secondary
- RNA, Bacterial/metabolism
- RNA, Ribosomal, 16S/metabolism
- Recombinant Proteins/metabolism
- Ribosomal Proteins/chemistry
- Ribosomal Proteins/genetics
- Ribosomal Proteins/isolation & purification
- Ribosomal Proteins/metabolism
- Sequence Alignment
- Thermus thermophilus/genetics
- Transcription, Genetic
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Affiliation(s)
- V Vysotskaya
- Department of Structure and Function of Ribosomes, Russian Academy of Sciences, Moscow Region
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44
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Keith G, Yusupov M, Briand C, Moras D, Kern D, Brion C [corrected to Briand C]. Sequence of tRNA(Asp) from Thermus thermophilus HB8. Nucleic Acids Res 1993; 21:4399. [PMID: 7692402 PMCID: PMC310085 DOI: 10.1093/nar/21.18.4399] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Affiliation(s)
- G Keith
- Unité Structure des Macromolécules Biologiques et Mécanismes de Reconnaissance UPR 9002 CNRS, Strasbourg, France
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45
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Reddy DM, Crain PF, Edmonds CG, Gupta R, Hashizume T, Stetter KO, Widdel F, McCloskey JA. Structure determination of two new amino acid-containing derivatives of adenosine from tRNA of thermophilic bacteria and archaea. Nucleic Acids Res 1992; 20:5607-15. [PMID: 1280806 PMCID: PMC334393 DOI: 10.1093/nar/20.21.5607] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Two new nucleosides have been identified in unfractionated transfer RNA of two thermophilic bacteria, Thermodesulfobacterium commune, and Thermotoga maritima, six hyperthermophilic archaea, including Pyrobaculum islandicum, Pyrococcus furiosus and Thermococcus sp. and two mesophilic archaea, Methanococcus vannielii and Methanolobus tindarius. Structures were determined primarily by mass spectrometry, as 3-hydroxy-N-[[(9-beta-D-ribofuranosyl-9H-purin-6- yl)amino]carbonyl]norvaline, (hn6A), structure 1, and 3-hydroxy-N-[[(9-beta-D-ribofuranosyl-9H-2-methylthiopurin-6- yl)amino]carbonyl]norvaline (ms2hn6A), 2. The amino acid side chain was characterized as 3-hydroxynorvaline (3) by gas chromatography-mass spectrometry of the trimethylsilyl derivative after cleavage from 1 and 2 by alkaline hydrolysis. Evidence for the amino acid-purine carbamoyl linkage was obtained from the collision-induced dissociation mass spectrum of trimethylsilylated 1, and the total structure was confirmed by chemical synthesis of 1.
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Affiliation(s)
- D M Reddy
- Department of Medicinal Chemistry, University of Utah, Salt Lake City 84112
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46
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Kawai G, Yamamoto Y, Kamimura T, Masegi T, Sekine M, Hata T, Iimori T, Watanabe T, Miyazawa T, Yokoyama S. Conformational rigidity of specific pyrimidine residues in tRNA arises from posttranscriptional modifications that enhance steric interaction between the base and the 2'-hydroxyl group. Biochemistry 1992; 31:1040-6. [PMID: 1310418 DOI: 10.1021/bi00119a012] [Citation(s) in RCA: 164] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In order to elucidate roles of the 2'-O-methylation of pyrimidine nucleotide residues of tRNAs, conformations of 2'-O-methyluridylyl(3'----5')uridine (UmpU), 2'-O-methyluridine 3'-monophosphate (Ump), and 2'-O-methyluridine (Um) in 2H2O solution were analyzed by one- and two-dimensional proton NMR spectroscopy and compared with those of related nucleotides and nucleoside. As for UpU and UmpU, the 2'-O-methylation was found to stabilize the C3'-endo form of the 3'-nucleotidyl unit (Up-/Ump-moiety). This stabilization of the C3'-endo form is primarily due to an intraresidue effect, since the conformation of the 5'-nucleotidyl unit (-pU moiety) was only slightly affected by the 2'-O-methylation of the 3'-nucleotide unit. In fact even for Up and Ump, the 2'-O-methylation significantly stabilizes the C3'-endo form by 0.8 kcal/.mol-1. By contrast, for nucleosides (U and Um), the C3'-endo form is slightly stabilized by 0.1 kcal/.mol-1. Accordingly, the stabilization of the C3'-endo form by the 2'-O-methylation is primarily due to the steric repulsion among the 2-carbonyl group, the 2'-O-methyl group and the 3'-phosphate group in the C2'-endo form. For some tRNA species, 2-thiolation of pyrimidine residues is found in positions where the 2'-O-methylation is found for other tRNA species.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- G Kawai
- Department of Biophysics and Biochemistry, Faculty of Science, University of Tokyo, Japan
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Kawai G, Hashizume T, Yasuda M, Miyazawa T, McCloskey JA, Yokoyama S. Conformational Rigidity of N4-Acetyl-2′-O-methylcytidine Found in tRNA of Extremely Thermophilic Archaebacteria (Archaea). ACTA ACUST UNITED AC 1992. [DOI: 10.1080/07328319208021740] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Edmonds CG, Crain PF, Gupta R, Hashizume T, Hocart CH, Kowalak JA, Pomerantz SC, Stetter KO, McCloskey JA. Posttranscriptional modification of tRNA in thermophilic archaea (Archaebacteria). J Bacteriol 1991; 173:3138-48. [PMID: 1708763 PMCID: PMC207908 DOI: 10.1128/jb.173.10.3138-3148.1991] [Citation(s) in RCA: 149] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Nucleoside modification has been studied in unfractionated tRNA from 11 thermophilic archaea (archaebacteria), including phylogenetically diverse representatives of thermophilic methanogens and sulfur-metabolizing hyperthermophiles which grow optimally in the temperature range of 56 (Thermoplasma acidophilum) to 105 degrees C (Pyrodictium occultum), and for comparison from the most thermophilic bacterium (eubacterium) known, Thermotoga maritima (80 degrees C). Nine nucleosides are found to be unique to the archaea, six of which are structurally novel in being modified both in the base and by methylation in ribose and occur primarily in tRNA from the extreme thermophiles in the Crenarchaeota of the archaeal phylogenetic tree. 2-Thiothymine occurs in tRNA from Thermococcus sp., and constitutes the only known occurrence of the thymine moiety in archaeal RNA, in contrast to its near-ubiquitous presence in tRNA from bacteria and eukarya. A total of 33 modified nucleosides are rigorously characterized in archaeal tRNA in the present study, demonstrating that the structural range of posttranscriptional modifications in archaeal tRNA is more extensive than previously known. From a phylogenetic standpoint, certain tRNA modifications occur in the archaea which are otherwise unique to either the bacterial or eukaryal domain, although the overall patterns of modification are more typical of eukaryotes than bacteria.
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Affiliation(s)
- C G Edmonds
- Department of Medicinal Chemistry, University of Utah, Salt Lake City 84112
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49
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Ishikawa T, Yoneda F, Tanaka K, Fuji K. Synthesis and properties of oligothymidylate containing sulfur-modified thymidine: effect of thiation of pyrimidine ring on the thermostability and conformation of the duplex. Bioorg Med Chem Lett 1991. [DOI: 10.1016/s0960-894x(01)80458-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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50
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Perret V, Garcia A, Puglisi J, Grosjean H, Ebel JP, Florentz C, Giegé R. Conformation in solution of yeast tRNA(Asp) transcripts deprived of modified nucleotides. Biochimie 1990; 72:735-43. [PMID: 2078590 DOI: 10.1016/0300-9084(90)90158-d] [Citation(s) in RCA: 107] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A synthetic gene of yeast aspartic acid tRNA with a promoter for phage T7 RNA polymerase was cloned in Escherichia coli. The in vitro transcribed tRNA(Asp) molecules are deprived of modified nucleotides and retain their aspartylation capacity. The solution conformation of these molecules was mapped with chemical structural probes and compared to that of fully modified molecules. Significant differences in reactivities were observed in Pb2+ cleavage of the RNAs and in modification of the bases with dimethyl sulphate. The most striking result concerns C56, which becomes reactive in unmodified tRNA(Asp), indicating the disruption of the C56-G19 base pair involved in the D- and T-loop interaction. The chemical data indicate that unmodified tRNA(Asp) transcripts possess a relaxed conformation compared to that of the native tRNA. This conclusion is confirmed by thermal melting experiments. Thus it can be proposed that post-transcriptional modifications of nucleotides in tRNA stabilize the biologically active conformations in these molecules.
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Affiliation(s)
- V Perret
- Institut de Biologie Moléculaire et Cellulaire, Centre National de la Recherche Scientifique, Strasbourg, France
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