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Zheng X, Su C, Duan L, Jin M, Sun Y, Zhu L, Zhang W. Molecular basis of A. thaliana KEOPS complex in biosynthesizing tRNA t6A. Nucleic Acids Res 2024; 52:4523-4540. [PMID: 38477398 PMCID: PMC11077089 DOI: 10.1093/nar/gkae179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 02/19/2024] [Accepted: 03/01/2024] [Indexed: 03/14/2024] Open
Abstract
In archaea and eukaryotes, the evolutionarily conserved KEOPS is composed of four core subunits-Kae1, Bud32, Cgi121 and Pcc1, and a fifth Gon7/Pcc2 that is found in fungi and metazoa. KEOPS cooperates with Sua5/YRDC to catalyze the biosynthesis of tRNA N6-threonylcarbamoyladenosine (t6A), an essential modification needed for fitness of cellular organisms. Biochemical and structural characterizations of KEOPSs from archaea, yeast and humans have determined a t6A-catalytic role for Kae1 and auxiliary roles for other subunits. However, the precise molecular workings of KEOPSs still remain poorly understood. Here, we investigated the biochemical functions of A. thaliana KEOPS and determined a cryo-EM structure of A. thaliana KEOPS dimer. We show that A. thaliana KEOPS is composed of KAE1, BUD32, CGI121 and PCC1, which adopts a conserved overall arrangement. PCC1 dimerization leads to a KEOPS dimer that is needed for an active t6A-catalytic KEOPS-tRNA assembly. BUD32 participates in direct binding of tRNA to KEOPS and modulates the t6A-catalytic activity of KEOPS via its C-terminal tail and ATP to ADP hydrolysis. CGI121 promotes the binding of tRNA to KEOPS and potentiates the t6A-catalytic activity of KEOPS. These data and findings provide insights into mechanistic understanding of KEOPS machineries.
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Affiliation(s)
- Xinxing Zheng
- School of Life Sciences, Key Laboratory of Cell Activities and Stress Adaptation of the Ministry of Education, Lanzhou University, Lanzhou 730000, China
| | - Chenchen Su
- School of Life Sciences, Key Laboratory of Cell Activities and Stress Adaptation of the Ministry of Education, Lanzhou University, Lanzhou 730000, China
| | - Lei Duan
- School of Life Sciences, Key Laboratory of Cell Activities and Stress Adaptation of the Ministry of Education, Lanzhou University, Lanzhou 730000, China
| | - Mengqi Jin
- School of Life Sciences, Key Laboratory of Cell Activities and Stress Adaptation of the Ministry of Education, Lanzhou University, Lanzhou 730000, China
| | - Yongtao Sun
- School of Life Sciences, Key Laboratory of Cell Activities and Stress Adaptation of the Ministry of Education, Lanzhou University, Lanzhou 730000, China
| | - Li Zhu
- School of Life Sciences, Key Laboratory of Cell Activities and Stress Adaptation of the Ministry of Education, Lanzhou University, Lanzhou 730000, China
| | - Wenhua Zhang
- School of Life Sciences, Key Laboratory of Cell Activities and Stress Adaptation of the Ministry of Education, Lanzhou University, Lanzhou 730000, 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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Smith TJ, Giles RN, Koutmou KS. Anticodon stem-loop tRNA modifications influence codon decoding and frame maintenance during translation. Semin Cell Dev Biol 2024; 154:105-113. [PMID: 37385829 DOI: 10.1016/j.semcdb.2023.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 06/06/2023] [Accepted: 06/07/2023] [Indexed: 07/01/2023]
Abstract
RNAs are central to protein synthesis, with ribosomal RNA, transfer RNAs and messenger RNAs comprising the core components of the translation machinery. In addition to the four canonical bases (uracil, cytosine, adenine, and guanine) these RNAs contain an array of enzymatically incorporated chemical modifications. Transfer RNAs (tRNAs) are responsible for ferrying amino acids to the ribosome, and are among the most abundant and highly modified RNAs in the cell across all domains of life. On average, tRNA molecules contain 13 post-transcriptionally modified nucleosides that stabilize their structure and enhance function. There is an extensive chemical diversity of tRNA modifications, with over 90 distinct varieties of modifications reported within tRNA sequences. Some modifications are crucial for tRNAs to adopt their L-shaped tertiary structure, while others promote tRNA interactions with components of the protein synthesis machinery. In particular, modifications in the anticodon stem-loop (ASL), located near the site of tRNA:mRNA interaction, can play key roles in ensuring protein homeostasis and accurate translation. There is an abundance of evidence indicating the importance of ASL modifications for cellular health, and in vitro biochemical and biophysical studies suggest that individual ASL modifications can differentially influence discrete steps in the translation pathway. This review examines the molecular level consequences of tRNA ASL modifications in mRNA codon recognition and reading frame maintenance to ensure the rapid and accurate translation of proteins.
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Affiliation(s)
- Tyler J Smith
- University of Michigan, Department of Chemistry, 930 N University, Ann Arbor, MI 48109, USA
| | - Rachel N Giles
- University of Michigan, Department of Chemistry, 930 N University, Ann Arbor, MI 48109, USA
| | - Kristin S Koutmou
- University of Michigan, Department of Chemistry, 930 N University, Ann Arbor, MI 48109, USA.
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Smoczynski J, Yared MJ, Meynier V, Barraud P, Tisné C. Advances in the Structural and Functional Understanding of m 1A RNA Modification. Acc Chem Res 2024. [PMID: 38331425 PMCID: PMC10882958 DOI: 10.1021/acs.accounts.3c00568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2024]
Abstract
ConspectusRNA modification is a co- or post-transcriptional process by which specific nucleotides are chemically altered by enzymes after their initial incorporation into the RNA chain, expanding the chemical and functional diversity of RNAs. Our understanding of RNA modifications has changed dramatically in recent years. In the past decade, RNA methyltransferases (MTases) have been highlighted in numerous clinical studies and disease models, modifications have been found to be dynamically regulated by demodification enzymes, and significant technological advances have been made in the fields of RNA sequencing, mass spectrometry, and structural biology. Among RNAs, transfer RNAs (tRNAs) exhibit the greatest diversity and density of post-transcriptional modifications, which allow for potential cross-talks and regulation during their incorporation. N1-methyladenosine (m1A) modification is found in tRNAs at positions 9, 14, 16, 22, 57, and 58, depending on the tRNA and organism.Our laboratory has used and developed a large panel of tools to decipher the different mechanisms used by m1A tRNA MTases to recognize and methylate tRNA. We have solved the structures of TrmI from Thermus thermophilus (m1A58), TrmK from Bacillus subtilis (m1A22), and human TRMT10C (m1A9). These MTases do not share the same structure or organization to recognize tRNAs, but they all modify an adenosine, forming a non-Watson-Crick (WC) interaction. For TrmK, nuclear magnetic resonance (NMR) chemical shift mapping of the binding interface between TrmK and tRNASer was invaluable to build a TrmK/tRNA model, where both domains of TrmK participate in the binding of a full-length L-shaped tRNA and where the non-WC purine 13-A22 base pair positions the A22 N1-atom close to the methyl of the S-adenosyl-l-methionine (SAM) TrmK cofactor. For TRMT10C, cryoEM structures showed the MTase poised to N1-methylate A9 or G9 in tRNA and revealed different steps of tRNA maturation, where TRMT10C acts as a tRNA binding platform for sequential docking of each maturation enzyme. This work confers a role for TRMT10C in tRNA quality control and provides a framework to understand the link between mitochondrial tRNA maturation dysfunction and diseases.Methods to directly detect the incorporation of modifications during tRNA biosynthesis are rare and do not provide easy access to the temporality of their introduction. To this end, we have introduced time-resolved NMR to monitor tRNA maturation in the cellular environment. Combined with genetic and biochemical approaches involving the synthesis of specifically modified tRNAs, our methodology revealed that some modifications are incorporated in a defined sequential order, controlled by cross-talks between modification events. In particular, a strong modification circuit, namely Ψ55 → m5U54 → m1A58, controls the modification process in the T-arm of yeast elongator tRNAs. Conversely, we showed that m1A58 is efficiently introduced on unmodified initiator tRNAiMet without the need of any prior modification. Two distinct pathways are therefore followed for m1A58 incorporation in elongator and initiator tRNAs.We are undoubtedly entering an exciting period for the elucidation of the functions of RNA modifications and the intricate mechanisms by which modification enzymes identify and alter their RNA substrates. These are promising directions for the field of epitranscriptomics.
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Affiliation(s)
- Jakub Smoczynski
- Université Paris Cité, CNRS, Institut de Biologie Physico-Chimique, IBPC, Expression Génétique Microbienne, Paris 75005, France
| | - Marcel-Joseph Yared
- Université Paris Cité, CNRS, Institut de Biologie Physico-Chimique, IBPC, Expression Génétique Microbienne, Paris 75005, France
| | - Vincent Meynier
- Université Paris Cité, CNRS, Institut de Biologie Physico-Chimique, IBPC, Expression Génétique Microbienne, Paris 75005, France
| | - Pierre Barraud
- Université Paris Cité, CNRS, Institut de Biologie Physico-Chimique, IBPC, Expression Génétique Microbienne, Paris 75005, France
| | - Carine Tisné
- Université Paris Cité, CNRS, Institut de Biologie Physico-Chimique, IBPC, Expression Génétique Microbienne, Paris 75005, France
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Bowles IE, Jackman JE. Diversity in Biological Function and Mechanism of the tRNA Methyltransferase Trm10. Acc Chem Res 2023; 56:3595-3603. [PMID: 38048440 DOI: 10.1021/acs.accounts.3c00533] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/06/2023]
Abstract
Transfer ribonucleic acid (tRNA) is the most highly modified RNA species in the cell, and loss of tRNA modifications can lead to growth defects in yeast as well as metabolic, neurological, and mitochondrial disorders in humans. Significant progress has been made toward identifying the enzymes that are responsible for installing diverse modifications in tRNA, revealing a landscape of fascinating biological and mechanistic diversity that remains to be fully explored. Most early discoveries of tRNA modification enzymes were in model systems, where many enzymes were not strictly required for viability, an observation somewhat at odds with the extreme conservation of many of the same enzymes throughout multiple domains of life. Moreover, many tRNA modification enzymes act on more than one type of tRNA substrate, which is not necessarily surprising given the similar overall secondary and tertiary structures of tRNA, yet biochemical characterization has revealed interesting patterns of substrate specificity that can be challenging to rationalize on a molecular level. Questions about how many enzymes efficiently select a precise set of target tRNAs from among a structurally similar pool of molecules persist.The tRNA methyltransferase Trm10 provides an exciting paradigm to study the biological and mechanistic questions surrounding tRNA modifications. Even though the enzyme was originally characterized in Saccharomyces cerevisiae where its deletion causes no detectable phenotype under standard lab conditions, several more recently identified phenotypes provide insight into the requirement for this modification in the overall quality control of the tRNA pool. Studies of Trm10 in yeast also revealed another characteristic feature that has turned out to be a conserved feature of enzymes throughout the Trm10 family tree. We were initially surprised to see that purified S. cerevisiae Trm10 was capable of modifying tRNA substrates that were not detectably modified by the enzyme in vivo in yeast. This pattern has continued to emerge as we and others have studied Trm10 orthologs from Archaea and Eukarya, with enzymes exhibiting in vitro substrate specificities that can differ significantly from in vivo patterns of modification. While this feature complicates efforts to predict substrate specificities of Trm10 enzymes in the absence of appropriate genetic systems, it also provides an exciting opportunity for studying how enzyme activities can be regulated to achieve dynamic patterns of biological tRNA modification, which have been shown to be increasingly important for stress responses and human disease. Finally, the intriguing diversity in target nucleotide modification that has been revealed among Trm10 orthologs is distinctive among known tRNA modifying enzymes and necessitates unusual and likely novel catalytic strategies for methylation that are being revealed by biochemical and structural studies directed toward various family members. These efforts will no doubt yield more surprising discoveries in terms of tRNA modification enzymology.
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Affiliation(s)
- Isobel E Bowles
- Department of Chemistry and Biochemistry, Center for RNA Biology and Ohio State Biochemistry Program, The Ohio State University, 484 W. 12th Avenue, Columbus, Ohio 43210, United States
| | - Jane E Jackman
- Department of Chemistry and Biochemistry, Center for RNA Biology and Ohio State Biochemistry Program, The Ohio State University, 484 W. 12th Avenue, Columbus, Ohio 43210, United States
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6
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Strassler SE, Bowles IE, Krishnamohan A, Kim H, Edgington CB, Kuiper EG, Hancock CJ, Comstock LR, Jackman JE, Conn GL. tRNA m 1G9 modification depends on substrate-specific RNA conformational changes induced by the methyltransferase Trm10. J Biol Chem 2023; 299:105443. [PMID: 37949221 PMCID: PMC10704376 DOI: 10.1016/j.jbc.2023.105443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 10/19/2023] [Accepted: 11/06/2023] [Indexed: 11/12/2023] Open
Abstract
The methyltransferase Trm10 modifies a subset of tRNAs on the base N1 position of the ninth nucleotide in the tRNA core. Trm10 is conserved throughout Eukarya and Archaea, and mutations in the human gene (TRMT10A) have been linked to neurological disorders such as microcephaly and intellectual disability, as well as defects in glucose metabolism. Of the 26 tRNAs in yeast with guanosine at position 9, only 13 are substrates for Trm10. However, no common sequence or other posttranscriptional modifications have been identified among these substrates, suggesting the presence of some other tRNA feature(s) that allow Trm10 to distinguish substrate from nonsubstrate tRNAs. Here, we show that substrate recognition by Saccharomyces cerevisiae Trm10 is dependent on both intrinsic tRNA flexibility and the ability of the enzyme to induce specific tRNA conformational changes upon binding. Using the sensitive RNA structure-probing method SHAPE, conformational changes upon binding to Trm10 in tRNA substrates, but not nonsubstrates, were identified and mapped onto a model of Trm10-bound tRNA. These changes may play an important role in substrate recognition by allowing Trm10 to gain access to the target nucleotide. Our results highlight a novel mechanism of substrate recognition by a conserved tRNA modifying enzyme. Further, these studies reveal a strategy for substrate recognition that may be broadly employed by tRNA-modifying enzymes which must distinguish between structurally similar tRNA species.
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Affiliation(s)
- Sarah E Strassler
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia, USA; Graduate Program in Biochemistry, Cell and Developmental Biology, Graduate Division of Biological and Biomedical Sciences, Emory University, Atlanta, Georgia, USA
| | - Isobel E Bowles
- Department of Chemistry and Biochemistry and Center for RNA Biology, The Ohio State University, Columbus, Ohio, USA; Ohio State Biochemistry Program, The Ohio State University, Columbus, Ohio, USA
| | - Aiswarya Krishnamohan
- Department of Chemistry and Biochemistry and Center for RNA Biology, The Ohio State University, Columbus, Ohio, USA; Ohio State Biochemistry Program, The Ohio State University, Columbus, Ohio, USA
| | - Hyejeong Kim
- Department of Chemistry and Biochemistry and Center for RNA Biology, The Ohio State University, Columbus, Ohio, USA
| | - Catherine B Edgington
- Department of Chemistry and Biochemistry and Center for RNA Biology, The Ohio State University, Columbus, Ohio, USA
| | - Emily G Kuiper
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia, USA; Graduate Program in Biochemistry, Cell and Developmental Biology, Graduate Division of Biological and Biomedical Sciences, Emory University, Atlanta, Georgia, USA
| | - Clio J Hancock
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Lindsay R Comstock
- Department of Chemistry, Wake Forest University, Winston-Salem, North Carolina, USA
| | - Jane E Jackman
- Department of Chemistry and Biochemistry and Center for RNA Biology, The Ohio State University, Columbus, Ohio, USA; Ohio State Biochemistry Program, The Ohio State University, Columbus, Ohio, USA.
| | - Graeme L Conn
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia, USA; Graduate Program in Biochemistry, Cell and Developmental Biology, Graduate Division of Biological and Biomedical Sciences, Emory University, Atlanta, Georgia, USA.
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7
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Yared MJ, Yoluç Y, Catala M, Tisné C, Kaiser S, Barraud P. Different modification pathways for m1A58 incorporation in yeast elongator and initiator tRNAs. Nucleic Acids Res 2023; 51:10653-10667. [PMID: 37650648 PMCID: PMC10602860 DOI: 10.1093/nar/gkad722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 08/18/2023] [Indexed: 09/01/2023] Open
Abstract
As essential components of the protein synthesis machinery, tRNAs undergo a tightly controlled biogenesis process, which include the incorporation of numerous posttranscriptional modifications. Defects in these tRNA maturation steps may lead to the degradation of hypomodified tRNAs by the rapid tRNA decay (RTD) and nuclear surveillance pathways. We previously identified m1A58 as a late modification introduced after modifications Ψ55 and T54 in yeast elongator tRNAPhe. However, previous reports suggested that m1A58 is introduced early during the tRNA modification process, in particular on primary transcripts of initiator tRNAiMet, which prevents its degradation by RNA decay pathways. Here, aiming to reconcile this apparent inconsistency on the temporality of m1A58 incorporation, we examined its introduction into yeast elongator and initiator tRNAs. We used specifically modified tRNAs to report on the molecular aspects controlling the Ψ55 → T54 → m1A58 modification circuit in elongator tRNAs. We also show that m1A58 is efficiently introduced on unmodified tRNAiMet, and does not depend on prior modifications. Finally, we show that m1A58 has major effects on the structural properties of initiator tRNAiMet, so that the tRNA elbow structure is only properly assembled when this modification is present. This observation provides a structural explanation for the degradation of hypomodified tRNAiMet lacking m1A58 by the nuclear surveillance and RTD pathways.
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Affiliation(s)
- Marcel-Joseph Yared
- Expression génétique microbienne, Université Paris Cité, CNRS, Institut de biologie physico-chimique, Paris, France
| | - Yasemin Yoluç
- Department of Chemistry, Ludwig Maximilians University, Munich, Germany
| | - Marjorie Catala
- Expression génétique microbienne, Université Paris Cité, CNRS, Institut de biologie physico-chimique, Paris, France
| | - Carine Tisné
- Expression génétique microbienne, Université Paris Cité, CNRS, Institut de biologie physico-chimique, Paris, France
| | - Stefanie Kaiser
- Department of Chemistry, Ludwig Maximilians University, Munich, Germany
- Institute of Pharmaceutical Chemistry, Goethe-University, Frankfurt, Germany
| | - Pierre Barraud
- Expression génétique microbienne, Université Paris Cité, CNRS, Institut de biologie physico-chimique, Paris, France
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8
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Strassler SE, Bowles IE, Krishnamohan A, Kim H, Edgington CB, Kuiper EG, Hancock CJ, Comstock LR, Jackman JE, Conn GL. tRNA m 1G9 modification depends on substrate-specific RNA conformational changes induced by the methyltransferase Trm10. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.01.526536. [PMID: 36778341 PMCID: PMC9915607 DOI: 10.1101/2023.02.01.526536] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The methyltransferase Trm10 modifies a subset of tRNAs on the base N1 position of the 9th nucleotide in the tRNA core. Trm10 is conserved throughout Eukarya and Archaea, and mutations in the human gene (TRMT10A) have been linked to neurological disorders such as microcephaly and intellectual disability, as well as defects in glucose metabolism. Of the 26 tRNAs in yeast with guanosine at position 9, only 14 are substrates for Trm10. However, no common sequence or other posttranscriptional modifications have been identified among these substrates, suggesting the presence of some other tRNA feature(s) which allow Trm10 to distinguish substrate from nonsubstrate tRNAs. Here, we show that substrate recognition by Saccharomyces cerevisiae Trm10 is dependent on both intrinsic tRNA flexibility and the ability of the enzyme to induce specific tRNA conformational changes upon binding. Using the sensitive RNA structure-probing method SHAPE, conformational changes upon binding to Trm10 in tRNA substrates, but not nonsubstrates, were identified and mapped onto a model of Trm10-bound tRNA. These changes may play an important role in substrate recognition by allowing Trm10 to gain access to the target nucleotide. Our results highlight a novel mechanism of substrate recognition by a conserved tRNA modifying enzyme. Further, these studies reveal a strategy for substrate recognition that may be broadly employed by tRNA-modifying enzymes which must distinguish between structurally similar tRNA species.
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Affiliation(s)
- Sarah E. Strassler
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road NE, Atlanta GA, 30322, USA
- Graduate Program in Biochemistry, Cell and Developmental Biology, Graduate Division of Biological and Biomedical Sciences, Emory University
| | - Isobel E. Bowles
- Department of Chemistry and Biochemistry, Center for RNA Biology and Ohio State Biochemistry Program, 484 W. 12 Avenue, Columbus, OH, 43210, USA
- Ohio State Biochemistry Program, The Ohio State University, 484 W. 12 Avenue, Columbus, OH, 43210, USA
| | - Aiswarya Krishnamohan
- Department of Chemistry and Biochemistry, Center for RNA Biology and Ohio State Biochemistry Program, 484 W. 12 Avenue, Columbus, OH, 43210, USA
- Ohio State Biochemistry Program, The Ohio State University, 484 W. 12 Avenue, Columbus, OH, 43210, USA
| | - Hyejeong Kim
- Department of Chemistry and Biochemistry, Center for RNA Biology and Ohio State Biochemistry Program, 484 W. 12 Avenue, Columbus, OH, 43210, USA
| | - Catherine B. Edgington
- Department of Chemistry and Biochemistry, Center for RNA Biology and Ohio State Biochemistry Program, 484 W. 12 Avenue, Columbus, OH, 43210, USA
| | - Emily G. Kuiper
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road NE, Atlanta GA, 30322, USA
- Graduate Program in Biochemistry, Cell and Developmental Biology, Graduate Division of Biological and Biomedical Sciences, Emory University
| | - Clio J. Hancock
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road NE, Atlanta GA, 30322, USA
| | - Lindsay R. Comstock
- Department of Chemistry, Wake Forest University, 1834 Wake Forest Road, Winston-Salem, NC 27106, USA
| | - Jane E. Jackman
- Department of Chemistry and Biochemistry, Center for RNA Biology and Ohio State Biochemistry Program, 484 W. 12 Avenue, Columbus, OH, 43210, USA
- Ohio State Biochemistry Program, The Ohio State University, 484 W. 12 Avenue, Columbus, OH, 43210, USA
| | - Graeme L. Conn
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road NE, Atlanta GA, 30322, USA
- Graduate Program in Biochemistry, Cell and Developmental Biology, Graduate Division of Biological and Biomedical Sciences, Emory University
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Cirzi C, Dyckow J, Legrand C, Schott J, Guo W, Perez Hernandez D, Hisaoka M, Parlato R, Pitzer C, van der Hoeven F, Dittmar G, Helm M, Stoecklin G, Schirmer L, Lyko F, Tuorto F. Queuosine-tRNA promotes sex-dependent learning and memory formation by maintaining codon-biased translation elongation speed. EMBO J 2023; 42:e112507. [PMID: 37609797 PMCID: PMC10548180 DOI: 10.15252/embj.2022112507] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 07/26/2023] [Accepted: 07/28/2023] [Indexed: 08/24/2023] Open
Abstract
Queuosine (Q) is a modified nucleoside at the wobble position of specific tRNAs. In mammals, queuosinylation is facilitated by queuine uptake from the gut microbiota and is introduced into tRNA by the QTRT1-QTRT2 enzyme complex. By establishing a Qtrt1 knockout mouse model, we discovered that the loss of Q-tRNA leads to learning and memory deficits. Ribo-Seq analysis in the hippocampus of Qtrt1-deficient mice revealed not only stalling of ribosomes on Q-decoded codons, but also a global imbalance in translation elongation speed between codons that engage in weak and strong interactions with their cognate anticodons. While Q-dependent molecular and behavioral phenotypes were identified in both sexes, female mice were affected more severely than males. Proteomics analysis confirmed deregulation of synaptogenesis and neuronal morphology. Together, our findings provide a link between tRNA modification and brain functions and reveal an unexpected role of protein synthesis in sex-dependent cognitive performance.
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Affiliation(s)
- Cansu Cirzi
- Division of Epigenetics, DKFZ‐ZMBH AllianceGerman Cancer Research Center (DKFZ)HeidelbergGermany
- Faculty of BiosciencesHeidelberg UniversityHeidelbergGermany
| | - Julia Dyckow
- Department of Neurology, Medical Faculty MannheimHeidelberg UniversityMannheimGermany
- Interdisciplinary Center for NeurosciencesHeidelberg UniversityHeidelbergGermany
| | - Carine Legrand
- Division of Epigenetics, DKFZ‐ZMBH AllianceGerman Cancer Research Center (DKFZ)HeidelbergGermany
- Université Paris Cité, Génomes, Biologie Cellulaire et Thérapeutique U944, INSERM, CNRSParisFrance
| | - Johanna Schott
- Center for Molecular Biology of Heidelberg University (ZMBH)DKFZ‐ZMBH AllianceHeidelbergGermany
- Division of Biochemistry, Mannheim Institute for Innate Immunoscience (MI3), Mannheim Cancer Center (MCC), Medical Faculty MannheimHeidelberg UniversityMannheimGermany
| | - Wei Guo
- Faculty of BiosciencesHeidelberg UniversityHeidelbergGermany
- Center for Molecular Biology of Heidelberg University (ZMBH)DKFZ‐ZMBH AllianceHeidelbergGermany
- Division of Biochemistry, Mannheim Institute for Innate Immunoscience (MI3), Mannheim Cancer Center (MCC), Medical Faculty MannheimHeidelberg UniversityMannheimGermany
| | | | - Miharu Hisaoka
- Center for Molecular Biology of Heidelberg University (ZMBH)DKFZ‐ZMBH AllianceHeidelbergGermany
- Division of Biochemistry, Mannheim Institute for Innate Immunoscience (MI3), Mannheim Cancer Center (MCC), Medical Faculty MannheimHeidelberg UniversityMannheimGermany
| | - Rosanna Parlato
- Division of Neurodegenerative Disorders, Department of Neurology, Medical Faculty Mannheim, Mannheim Center for Translational NeurosciencesHeidelberg UniversityMannheimGermany
| | - Claudia Pitzer
- Interdisciplinary Neurobehavioral Core (INBC), Medical Faculty HeidelbergHeidelberg UniversityHeidelbergGermany
| | | | - Gunnar Dittmar
- Department of Infection and ImmunityLuxembourg Institute of HealthStrassenLuxembourg
- Department of Life Sciences and MedicineUniversity of LuxembourgLuxembourg
| | - Mark Helm
- Institute of Pharmaceutical and Biomedical Science (IPBS)Johannes Gutenberg‐University MainzMainzGermany
| | - Georg Stoecklin
- Faculty of BiosciencesHeidelberg UniversityHeidelbergGermany
- Center for Molecular Biology of Heidelberg University (ZMBH)DKFZ‐ZMBH AllianceHeidelbergGermany
- Division of Biochemistry, Mannheim Institute for Innate Immunoscience (MI3), Mannheim Cancer Center (MCC), Medical Faculty MannheimHeidelberg UniversityMannheimGermany
| | - Lucas Schirmer
- Department of Neurology, Medical Faculty MannheimHeidelberg UniversityMannheimGermany
- Interdisciplinary Center for NeurosciencesHeidelberg UniversityHeidelbergGermany
- Mannheim Center for Translational Neuroscience and Institute for Innate Immunoscience, Medical Faculty MannheimHeidelberg UniversityMannheimGermany
| | - Frank Lyko
- Division of Epigenetics, DKFZ‐ZMBH AllianceGerman Cancer Research Center (DKFZ)HeidelbergGermany
| | - Francesca Tuorto
- Division of Epigenetics, DKFZ‐ZMBH AllianceGerman Cancer Research Center (DKFZ)HeidelbergGermany
- Center for Molecular Biology of Heidelberg University (ZMBH)DKFZ‐ZMBH AllianceHeidelbergGermany
- Division of Biochemistry, Mannheim Institute for Innate Immunoscience (MI3), Mannheim Cancer Center (MCC), Medical Faculty MannheimHeidelberg UniversityMannheimGermany
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10
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Huang MH, Wang JT, Zhang JH, Mao XL, Peng GX, Lin X, Lv D, Yuan C, Lin H, Wang ED, Zhou XL. Mitochondrial RNA m 3C methyltransferase METTL8 relies on an isoform-specific N-terminal extension and modifies multiple heterogenous tRNAs. Sci Bull (Beijing) 2023; 68:2094-2105. [PMID: 37573249 DOI: 10.1016/j.scib.2023.08.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 06/27/2023] [Accepted: 06/30/2023] [Indexed: 08/14/2023]
Abstract
Methyltransferase-like 8 (METTL8) encodes a mitochondria-localized METTL8-Iso1 and a nucleolus-distributed METTL8-Iso4 isoform, which differ only in their N-terminal extension (N-extension), by mRNA alternative splicing. METTL8-Iso1 generates 3-methylcytidine at position 32 (m3C32) of mitochondrial tRNAThr and tRNASer(UCN). Whether METTL8-Iso4 is an active m3C32 methyltransferase and the role of the N-extension in mitochondrial tRNA m3C32 formation remain unclear. Here, we revealed that METTL8-Iso4 was inactive in m3C32 generation due to the lack of N-extension, which contains several absolutely conserved modification-critical residues; the counterparts were likewise essential in cytoplasmic m3C32 biogenesis by methyltransferase-like 2A (METTL2A) or budding yeasts tRNA N3-methylcytidine methyltransferase (Trm140), in vitro and in vivo. Cross-compartment/species tRNA modification assays unexpectedly found that METTL8-Iso1 efficiently introduced m3C32 to several cytoplasmic or even bacterial tRNAs in vitro. m3C32 did not influence tRNAThrN6-threonylcarbamoyladenosine (t6A) modification or aminoacylation. In addition to its interaction with mitochondrial seryl-tRNA synthetase (SARS2), we further discovered an interaction between mitochondrial threonyl-tRNA synthetase (TARS2) and METTL8-Iso1. METTL8-Iso1 substantially stimulated the aminoacylation activities of SARS2 and TARS2 in vitro, suggesting a functional connection between mitochondrial tRNA modification and charging. Altogether, our results deepen the mechanistic insights into mitochondrial m3C32 biogenesis and provide a valuable route to prepare cytoplasmic/bacterial tRNAs with only a m3C32 moiety, aiding in future efforts to investigate its effects on tRNA structure and function.
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Affiliation(s)
- Meng-Han Huang
- Key Laboratory of RNA Science and Engineering, State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, China
| | - Jin-Tao Wang
- Key Laboratory of RNA Science and Engineering, State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, China
| | - Jian-Hui Zhang
- Key Laboratory of RNA Science and Engineering, State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, China; Key Laboratory of Systems Health Science of Zhejiang Province, School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China
| | - Xue-Ling Mao
- Key Laboratory of RNA Science and Engineering, State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, China
| | - Gui-Xin Peng
- Key Laboratory of RNA Science and Engineering, State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, China; School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Xiuying Lin
- State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou 570228, China; School of Life Sciences, Hainan University, Haikou 570228, China
| | - Daizhu Lv
- Analysis and Testing Center, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China
| | - Chen Yuan
- School of Pharmacy, China Pharmaceutical University, Nanjing 211198, China
| | - Huan Lin
- State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou 570228, China
| | - En-Duo Wang
- Key Laboratory of RNA Science and Engineering, State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, China; School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China.
| | - Xiao-Long Zhou
- Key Laboratory of RNA Science and Engineering, State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, China; Key Laboratory of Systems Health Science of Zhejiang Province, School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China.
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11
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Biela A, Hammermeister A, Kaczmarczyk I, Walczak M, Koziej L, Lin TY, Glatt S. The diverse structural modes of tRNA binding and recognition. J Biol Chem 2023; 299:104966. [PMID: 37380076 PMCID: PMC10424219 DOI: 10.1016/j.jbc.2023.104966] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 06/20/2023] [Accepted: 06/22/2023] [Indexed: 06/30/2023] Open
Abstract
tRNAs are short noncoding RNAs responsible for decoding mRNA codon triplets, delivering correct amino acids to the ribosome, and mediating polypeptide chain formation. Due to their key roles during translation, tRNAs have a highly conserved shape and large sets of tRNAs are present in all living organisms. Regardless of sequence variability, all tRNAs fold into a relatively rigid three-dimensional L-shaped structure. The conserved tertiary organization of canonical tRNA arises through the formation of two orthogonal helices, consisting of the acceptor and anticodon domains. Both elements fold independently to stabilize the overall structure of tRNAs through intramolecular interactions between the D- and T-arm. During tRNA maturation, different modifying enzymes posttranscriptionally attach chemical groups to specific nucleotides, which not only affect translation elongation rates but also restrict local folding processes and confer local flexibility when required. The characteristic structural features of tRNAs are also employed by various maturation factors and modification enzymes to assure the selection, recognition, and positioning of specific sites within the substrate tRNAs. The cellular functional repertoire of tRNAs continues to extend well beyond their role in translation, partly, due to the expanding pool of tRNA-derived fragments. Here, we aim to summarize the most recent developments in the field to understand how three-dimensional structure affects the canonical and noncanonical functions of tRNA.
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Affiliation(s)
- Anna Biela
- Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland
| | | | - Igor Kaczmarczyk
- Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland; Doctoral School of Exact and Natural Sciences, Jagiellonian University, Krakow, Poland
| | - Marta Walczak
- Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland; Doctoral School of Exact and Natural Sciences, Jagiellonian University, Krakow, Poland
| | - Lukasz Koziej
- Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland
| | - Ting-Yu Lin
- Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland.
| | - Sebastian Glatt
- Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland.
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12
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Chen AY, Owens MC, Liu KF. Coordination of RNA modifications in the brain and beyond. Mol Psychiatry 2023; 28:2737-2749. [PMID: 37138184 DOI: 10.1038/s41380-023-02083-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 04/12/2023] [Accepted: 04/18/2023] [Indexed: 05/05/2023]
Abstract
Gene expression regulation is a critical process throughout the body, especially in the nervous system. One mechanism by which biological systems regulate gene expression is via enzyme-mediated RNA modifications, also known as epitranscriptomic regulation. RNA modifications, which have been found on nearly all RNA species across all domains of life, are chemically diverse covalent modifications of RNA nucleotides and represent a robust and rapid mechanism for the regulation of gene expression. Although numerous studies have been conducted regarding the impact that single modifications in single RNA molecules have on gene expression, emerging evidence highlights potential crosstalk between and coordination of modifications across RNA species. These potential coordination axes of RNA modifications have emerged as a new direction in the field of epitranscriptomic research. In this review, we will highlight several examples of gene regulation via RNA modification in the nervous system, followed by a summary of the current state of the field of RNA modification coordination axes. In doing so, we aim to inspire the field to gain a deeper understanding of the roles of RNA modifications and coordination of these modifications in the nervous system.
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Affiliation(s)
- Anthony Yulin Chen
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Department of Chemistry and Biochemistry, Swarthmore College, Swarthmore, PA, 19081, USA
| | - Michael C Owens
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Graduate Group in Biochemistry and Molecular Biophysics, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Kathy Fange Liu
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA, 19104, USA.
- Graduate Group in Biochemistry and Molecular Biophysics, University of Pennsylvania, Philadelphia, PA, 19104, USA.
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13
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Abstract
The study of eukaryotic tRNA processing has given rise to an explosion of new information and insights in the last several years. We now have unprecedented knowledge of each step in the tRNA processing pathway, revealing unexpected twists in biochemical pathways, multiple new connections with regulatory pathways, and numerous biological effects of defects in processing steps that have profound consequences throughout eukaryotes, leading to growth phenotypes in the yeast Saccharomyces cerevisiae and to neurological and other disorders in humans. This review highlights seminal new results within the pathways that comprise the life of a tRNA, from its birth after transcription until its death by decay. We focus on new findings and revelations in each step of the pathway including the end-processing and splicing steps, many of the numerous modifications throughout the main body and anticodon loop of tRNA that are so crucial for tRNA function, the intricate tRNA trafficking pathways, and the quality control decay pathways, as well as the biogenesis and biology of tRNA-derived fragments. We also describe the many interactions of these pathways with signaling and other pathways in the cell.
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Affiliation(s)
- Eric M Phizicky
- Department of Biochemistry and Biophysics and Center for RNA Biology, University of Rochester School of Medicine, Rochester, New York 14642, USA
| | - Anita K Hopper
- Department of Molecular Genetics and Center for RNA Biology, Ohio State University, Columbus, Ohio 43235, USA
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14
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Schultz SK, Kothe U. Fluorescent labeling of tRNA for rapid kinetic interaction studies with tRNA-binding proteins. Methods Enzymol 2023; 692:103-126. [PMID: 37925176 DOI: 10.1016/bs.mie.2023.05.007] [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] [Indexed: 11/06/2023]
Abstract
Transfer RNA (tRNA) plays a critical role during translation and interacts with numerous proteins during its biogenesis, functional cycle and degradation. In particular, tRNA is extensively post-transcriptionally modified by various tRNA modifying enzymes which each target a specific nucleotide at different positions within tRNAs to introduce different chemical modifications. Fluorescent assays can be used to study the interaction between a protein and tRNA. Moreover, rapid mixing fluorescence stopped-flow assays provide insights into the kinetics of the tRNA-protein interaction in order to elucidate the tRNA binding mechanism for the given protein. A prerequisite for these studies is a fluorescently labeled molecule, such as fluorescent tRNA, wherein a change in fluorescence occurs upon protein binding. In this chapter, we discuss the utilization of tRNA modifications in order to introduce fluorophores at particular positions within tRNAs. Particularly, we focus on in vitro thiolation of a uridine at position 8 within tRNAs using the tRNA modification enzyme ThiI, followed by labeling of the thiol group with fluorescein. As such, this fluorescently labeled tRNA is primarily unmodified, with the exception of the thiolation modification to which the fluorophore is attached, and can be used as a substrate to study the binding of different tRNA-interacting factors. Herein, we discuss the example of studying the tRNA binding mechanism of the tRNA modifying enzymes TrmB and DusA using internally fluorescein-labeled tRNA.
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Affiliation(s)
- Sarah K Schultz
- Alberta RNA Research and Training Institute (ARRTI), Department of Chemistry and Biochemistry, University of Lethbridge, Lethbridge, AB, Canada; Department of Chemistry, University of Manitoba, Winnipeg, MB, Canada
| | - Ute Kothe
- Alberta RNA Research and Training Institute (ARRTI), Department of Chemistry and Biochemistry, University of Lethbridge, Lethbridge, AB, Canada; Department of Chemistry, University of Manitoba, Winnipeg, MB, Canada.
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15
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Keszthelyi TM, Tory K. The importance of pseudouridylation: human disorders related to the fifth nucleoside. Biol Futur 2023:10.1007/s42977-023-00158-3. [PMID: 37000312 DOI: 10.1007/s42977-023-00158-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 03/09/2023] [Indexed: 04/01/2023]
Abstract
Pseudouridylation is one of the most abundant RNA modifications in eukaryotes, making pseudouridine known as the "fifth nucleoside." This highly conserved alteration affects all non-coding and coding RNA types. Its role and importance have been increasingly widely researched, especially considering that its absence or damage leads to serious hereditary diseases. Here, we summarize the human genetic disorders described to date that are related to the participants of the pseudouridylation process.
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Affiliation(s)
| | - Kálmán Tory
- Department of Pediatrics, Semmelweis University, Budapest, Hungary
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16
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Yamagami R, Hori H. Functional analysis of tRNA modification enzymes using mutational profiling. Methods Enzymol 2023; 692:69-101. [PMID: 37925188 DOI: 10.1016/bs.mie.2023.02.021] [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] [Indexed: 11/06/2023]
Abstract
Transfer RNA (tRNA) delivers amino acids to the ribosome and functions as an essential adapter molecule for decoding codons on the messenger RNA (mRNA) during protein synthesis. Before attaining their proper activity, tRNAs undergo multiple post-transcriptional modifications with highly diversified roles such as stabilization of the tRNA structure, recognition of aminoacyl tRNA synthetases, precise codon-anticodon recognition, support of viral replication and onset of immune responses. The synthesis of the majority of modified nucleosides is catalyzed by a site-specific tRNA modification enzyme. This chapter provides a detailed protocol for using mutational profiling to analyze the enzymatic function of a tRNA methyltransferase in a high-throughput manner. In a previous study, we took tRNA m1A22 methyltransferase TrmK from Geobacillus stearothermophilus as a model tRNA methyltransferase and applied this protocol to gain mechanistic insights into how TrmK recognizes the substrate tRNAs. In theory, this protocol can be used unaltered for studying enzymes that catalyze modifications at the Watson-Crick face such as 1-methyladenosine (m1A), 3-methylcytosine (m3C), 3-methyluridine (m3U), 1-methylguanosine (m1G), and N2,N2-dimethylguanosine (m22G).
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Affiliation(s)
- Ryota Yamagami
- Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, Matsuyama, Ehime, Japan.
| | - Hiroyuki Hori
- Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, Matsuyama, Ehime, Japan.
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17
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Fang Z, Lu Z, Han S, Zhou Y, Yang W, Zhang X, Zhou X. The Transcriptome-Wide Mapping of 2-Methylthio- N6-isopentenyladenosine at Single-Base Resolution. J Am Chem Soc 2023; 145:5467-5473. [PMID: 36820840 DOI: 10.1021/jacs.2c13894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
Hundreds of modified bases have been identified and enzymatically modified to transfer RNAs (tRNAs) to regulate RNA function in various organisms. 2-Methylthio-N6-isopentenyladenosine (ms2i6A), a hypermodified base found at tRNA position 37, exists in both prokaryotes and eukaryotes. ms2i6A is traditionally identified by separating and digesting each tRNA from total RNA using RNA mass spectrometry. A transcriptome-wide and single-base resolution method that enables absolute mapping of ms2i6A along with analysis of its distribution in different RNAs is lacking. Here, through chemoselective methylthio group bioconjugation, we introduce a new approach (redox activated chemical tagging sequencing, ReACT-seq) to detect ms2i6A transcriptome-wide at single-base resolution. Using the chemoselectivity between the methylthio group and oxaziridine group, ms2i6A is bio-orthogonally tagged with an azide group without interference of canonical nucleotides, advancing enrichment of methylthio group modified RNAs prior to sequencing. ReACT-seq was demonstrated on nine known tRNAs and proved to be highly accurate, and the reverse transcription stop (RT-stop) character enables ReACT-seq detection at single-base resolution. In addition, ReACT-seq identified that the modification of ms2i6A is conservative and may not exist in other RNAs.
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Affiliation(s)
- Zhentian Fang
- College of Chemistry and Molecular Sciences, Department of Hematology of Zhongnan Hospital, Taikang Center for Life and Medical Sciences, Wuhan University, Wuhan, Hubei 430072, People's Republic of China
| | - Ziang Lu
- College of Chemistry and Molecular Sciences, Department of Hematology of Zhongnan Hospital, Taikang Center for Life and Medical Sciences, Wuhan University, Wuhan, Hubei 430072, People's Republic of China
| | - Shaoqing Han
- College of Chemistry and Molecular Sciences, Department of Hematology of Zhongnan Hospital, Taikang Center for Life and Medical Sciences, Wuhan University, Wuhan, Hubei 430072, People's Republic of China
| | - Yuanyuan Zhou
- State Key Laboratory of Virology and Medical Research Institute, Hubei Province Key Laboratory of Allergy and Immunology and Department of Immunology, Wuhan University School of Medicine, Wuhan 430071, People's Republic of China
| | - Wei Yang
- College of Chemistry and Molecular Sciences, Department of Hematology of Zhongnan Hospital, Taikang Center for Life and Medical Sciences, Wuhan University, Wuhan, Hubei 430072, People's Republic of China
| | - Xiaolian Zhang
- State Key Laboratory of Virology and Medical Research Institute, Hubei Province Key Laboratory of Allergy and Immunology and Department of Immunology, Wuhan University School of Medicine, Wuhan 430071, People's Republic of China
| | - Xiang Zhou
- College of Chemistry and Molecular Sciences, Department of Hematology of Zhongnan Hospital, Taikang Center for Life and Medical Sciences, Wuhan University, Wuhan, Hubei 430072, People's Republic of China
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18
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Cho G, Lee J, Kim J. Identification of a novel 5-aminomethyl-2-thiouridine methyltransferase in tRNA modification. Nucleic Acids Res 2023; 51:1971-1983. [PMID: 36762482 PMCID: PMC9976899 DOI: 10.1093/nar/gkad048] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 01/07/2023] [Accepted: 01/18/2023] [Indexed: 02/11/2023] Open
Abstract
The uridine at the 34th position of tRNA, which is able to base pair with the 3'-end codon on mRNA, is usually modified to influence many aspects of decoding properties during translation. Derivatives of 5-methyluridine (xm5U), which include methylaminomethyl (mnm-) or carboxymethylaminomethyl (cmnm-) groups at C5 of uracil base, are widely conserved at the 34th position of many prokaryotic tRNAs. In Gram-negative bacteria such as Escherichia coli, a bifunctional MnmC is involved in the last two reactions of the biosynthesis of mnm5(s2)U, in which the enzyme first converts cmnm5(s2)U to 5-aminomethyl-(2-thio)uridine (nm5(s2)U) and subsequently installs the methyl group to complete the formation of mnm5(s2)U. Although mnm5s2U has been identified in tRNAs of Gram-positive bacteria and plants as well, their genomes do not contain an mnmC ortholog and the gene(s) responsible for this modification is unknown. We discovered that MnmM, previously known as YtqB, is the methyltransferase that converts nm5s2U to mnm5s2U in Bacillus subtilis through comparative genomics, gene complementation experiments, and in vitro assays. Furthermore, we determined X-ray crystal structures of MnmM complexed with anticodon stem loop of tRNAGln. The structures provide the molecular basis underlying the importance of U33-nm5s2U34-U35 as the key determinant for the specificity of MnmM.
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Affiliation(s)
- Gyuhyeok Cho
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Korea
| | - Jangmin Lee
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Korea
| | - Jungwook Kim
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Korea
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19
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Sekulovski S, Trowitzsch S. What connects splicing of transfer RNA precursor molecules with pontocerebellar hypoplasia? Bioessays 2023; 45:e2200130. [PMID: 36517085 DOI: 10.1002/bies.202200130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Revised: 11/28/2022] [Accepted: 11/30/2022] [Indexed: 01/19/2023]
Abstract
Transfer RNAs (tRNAs) represent the most abundant class of RNA molecules in the cell and are key players during protein synthesis and cellular homeostasis. Aberrations in the extensive tRNA biogenesis pathways lead to severe neurological disorders in humans. Mutations in the tRNA splicing endonuclease (TSEN) and its associated RNA kinase cleavage factor polyribonucleotide kinase subunit 1 (CLP1) cause pontocerebellar hypoplasia (PCH), a heterogeneous group of neurodegenerative disorders, that manifest as underdevelopment of specific brain regions typically accompanied by microcephaly, profound motor impairments, and child mortality. Recently, we demonstrated that mutations leading to specific PCH subtypes destabilize TSEN in vitro and cause imbalances of immature to mature tRNA ratios in patient-derived cells. However, how tRNA processing defects translate to disease on a systems level has not been understood. Recent findings suggested that other cellular processes may be affected by mutations in TSEN/CLP1 and obscure the molecular mechanisms of PCH emergence. Here, we review PCH disease models linked to the TSEN/CLP1 machinery and discuss future directions to study neuropathogenesis.
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Affiliation(s)
- Samoil Sekulovski
- Institute of Biochemistry, Biocenter, Goethe University Frankfurt, Frankfurt/Main, Germany
| | - Simon Trowitzsch
- Institute of Biochemistry, Biocenter, Goethe University Frankfurt, Frankfurt/Main, Germany
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20
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Cui W, Zhao D, Jiang J, Tang F, Zhang C, Duan C. tRNA Modifications and Modifying Enzymes in Disease, the Potential Therapeutic Targets. Int J Biol Sci 2023; 19:1146-1162. [PMID: 36923941 PMCID: PMC10008702 DOI: 10.7150/ijbs.80233] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Accepted: 01/26/2023] [Indexed: 03/14/2023] Open
Abstract
tRNA is one of the most conserved and abundant RNA species, which plays a key role during protein translation. tRNA molecules are post-transcriptionally modified by tRNA modifying enzymes. Since high-throughput sequencing technology has developed rapidly, tRNA modification types have been discovered in many research fields. In tRNA, numerous types of tRNA modifications and modifying enzymes have been implicated in biological functions and human diseases. In our review, we talk about the relevant biological functions of tRNA modifications, including tRNA stability, protein translation, cell cycle, oxidative stress, and immunity. We also explore how tRNA modifications contribute to the progression of human diseases. Based on previous studies, we discuss some emerging techniques for assessing tRNA modifications to aid in discovering different types of tRNA modifications.
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Affiliation(s)
- Weifang Cui
- Department of Thoracic Surgery, Xiangya Hospital, Central South University, Xiangya Road 87th, Changsha, 410008, Hunan, PR China.,Hunan Engineering Research Center for Pulmonary Nodules Precise Diagnosis & Treatment, Changsha, 410008, Hunan, PR China
| | - Deze Zhao
- Department of Thoracic Surgery, Xiangya Hospital, Central South University, Xiangya Road 87th, Changsha, 410008, Hunan, PR China.,Hunan Engineering Research Center for Pulmonary Nodules Precise Diagnosis & Treatment, Changsha, 410008, Hunan, PR China
| | - Junjie Jiang
- Department of Thoracic Surgery, Xiangya Hospital, Central South University, Xiangya Road 87th, Changsha, 410008, Hunan, PR China.,Hunan Engineering Research Center for Pulmonary Nodules Precise Diagnosis & Treatment, Changsha, 410008, Hunan, PR China
| | - Faqing Tang
- Hunan Key Laboratory of Oncotarget Gene, Hunan Cancer Hospital & The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha 410008, Hunan, PR China
| | - Chunfang Zhang
- Department of Thoracic Surgery, Xiangya Hospital, Central South University, Xiangya Road 87th, Changsha, 410008, Hunan, PR China.,Hunan Engineering Research Center for Pulmonary Nodules Precise Diagnosis & Treatment, Changsha, 410008, Hunan, PR China
| | - Chaojun Duan
- Department of Thoracic Surgery, Xiangya Hospital, Central South University, Xiangya Road 87th, Changsha, 410008, Hunan, PR China.,Hunan Engineering Research Center for Pulmonary Nodules Precise Diagnosis & Treatment, Changsha, 410008, Hunan, PR China.,National Clinical Research Center for Geriatric Disorders, Changsha, 410008, Hunan, PR China.,Institute of Medical Sciences, Xiangya Lung Cancer Center, Xiangya Hospital, Central South University, Changsha 410008, Hunan, PR China
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21
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Conservation and Diversification of tRNA t6A-Modifying Enzymes across the Three Domains of Life. Int J Mol Sci 2022; 23:ijms232113600. [PMID: 36362385 PMCID: PMC9654439 DOI: 10.3390/ijms232113600] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Revised: 10/28/2022] [Accepted: 11/04/2022] [Indexed: 11/09/2022] Open
Abstract
The universal N6-threonylcarbamoyladenosine (t6A) modification occurs at position 37 of tRNAs that decipher codons starting with adenosine. Mechanistically, t6A stabilizes structural configurations of the anticodon stem loop, promotes anticodon–codon pairing and safeguards the translational fidelity. The biosynthesis of tRNA t6A is co-catalyzed by two universally conserved protein families of TsaC/Sua5 (COG0009) and TsaD/Kae1/Qri7 (COG0533). Enzymatically, TsaC/Sua5 protein utilizes the substrates of L-threonine, HCO3−/CO2 and ATP to synthesize an intermediate L-threonylcarbamoyladenylate, of which the threonylcarbamoyl-moiety is subsequently transferred onto the A37 of substrate tRNAs by the TsaD–TsaB –TsaE complex in bacteria or by the KEOPS complex in archaea and eukaryotic cytoplasm, whereas Qri7/OSGEPL1 protein functions on its own in mitochondria. Depletion of tRNA t6A interferes with protein homeostasis and gravely affects the life of unicellular organisms and the fitness of higher eukaryotes. Pathogenic mutations of YRDC, OSGEPL1 and KEOPS are implicated in a number of human mitochondrial and neurological diseases, including autosomal recessive Galloway–Mowat syndrome. The molecular mechanisms underscoring both the biosynthesis and cellular roles of tRNA t6A are presently not well elucidated. This review summarizes current mechanistic understandings of the catalysis, regulation and disease implications of tRNA t6A-biosynthetic machineries of three kingdoms of life, with a special focus on delineating the structure–function relationship from perspectives of conservation and diversity.
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22
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White LK, Hesselberth JR. Modification mapping by nanopore sequencing. Front Genet 2022; 13:1037134. [DOI: 10.3389/fgene.2022.1037134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Accepted: 10/07/2022] [Indexed: 11/13/2022] Open
Abstract
Next generation sequencing (NGS) has provided biologists with an unprecedented view into biological processes and their regulation over the past 2 decades, fueling a wave of development of high throughput methods based on short read DNA and RNA sequencing. For nucleic acid modifications, NGS has been coupled with immunoprecipitation, chemical treatment, enzymatic treatment, and/or the use of reverse transcriptase enzymes with fortuitous activities to enrich for and to identify covalent modifications of RNA and DNA. However, the majority of nucleic acid modifications lack commercial monoclonal antibodies, and mapping techniques that rely on chemical or enzymatic treatments to manipulate modification signatures add additional technical complexities to library preparation. Moreover, such approaches tend to be specific to a single class of RNA or DNA modification, and generate only indirect readouts of modification status. Third generation sequencing technologies such as the commercially available “long read” platforms from Pacific Biosciences and Oxford Nanopore Technologies are an attractive alternative for high throughput detection of nucleic acid modifications. While the former can indirectly sense modified nucleotides through changes in the kinetics of reverse transcription reactions, nanopore sequencing can in principle directly detect any nucleic acid modification that produces a signal distortion as the nucleic acid passes through a nanopore sensor embedded within a charged membrane. To date, more than a dozen endogenous DNA and RNA modifications have been interrogated by nanopore sequencing, as well as a number of synthetic nucleic acid modifications used in metabolic labeling, structure probing, and other emerging applications. This review is intended to introduce the reader to nanopore sequencing and key principles underlying its use in direct detection of nucleic acid modifications in unamplified DNA or RNA samples, and outline current approaches for detecting and quantifying nucleic acid modifications by nanopore sequencing. As this technology matures, we anticipate advances in both sequencing chemistry and analysis methods will lead to rapid improvements in the identification and quantification of these epigenetic marks.
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Sequential action of a tRNA base editor in conversion of cytidine to pseudouridine. Nat Commun 2022; 13:5994. [PMID: 36220828 PMCID: PMC9553926 DOI: 10.1038/s41467-022-33714-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 09/28/2022] [Indexed: 11/08/2022] Open
Abstract
Post-transcriptional RNA editing modulates gene expression in a condition-dependent fashion. We recently discovered C-to-Ψ editing in Vibrio cholerae tRNA. Here, we characterize the biogenesis, regulation, and functions of this previously undescribed RNA editing process. We show that an enzyme, TrcP, mediates the editing of C-to-U followed by the conversion of U to Ψ, consecutively. AlphaFold-2 predicts that TrcP consists of two globular domains (cytidine deaminase and pseudouridylase) and a long helical domain. The latter domain tethers tRNA substrates during both the C-to-U editing and pseudouridylation, likely enabling a substrate channeling mechanism for efficient catalysis all the way to the terminal product. C-to-Ψ editing both requires and suppresses other modifications, creating an interdependent network of modifications in the tRNA anticodon loop that facilitates coupling of tRNA modification states to iron availability. Our findings provide mechanistic insights into an RNA editing process that likely promotes environmental adaptation.
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24
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tRNA methylation resolves codon usage bias at the limit of cell viability. Cell Rep 2022; 41:111539. [PMID: 36288695 PMCID: PMC9643105 DOI: 10.1016/j.celrep.2022.111539] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 07/31/2022] [Accepted: 09/29/2022] [Indexed: 11/21/2022] Open
Abstract
Codon usage of each genome is closely correlated with the abundance of tRNA isoacceptors. How codon usage bias is resolved by tRNA post-transcriptional modifications is largely unknown. Here we demonstrate that the N1-methylation of guanosine at position 37 (m1G37) on the 3′-side of the anticodon, while not directly responsible for reading of codons, is a neutralizer that resolves differential decoding of proline codons. A genome-wide suppressor screen of a non-viable Escherichia coli strain, lacking m1G37, identifies proS suppressor mutations, indicating a coupling of methylation with tRNA prolyl-aminoacylation that sets the limit of cell viability. Using these suppressors, where prolyl-aminoacylation is decoupled from tRNA methylation, we show that m1G37 neutralizes differential translation of proline codons by the major isoacceptor. Lack of m1G37 inactivates this neutralization and exposes the need for a minor isoacceptor for cell viability. This work has medical implications for bacterial species that exclusively use the major isoacceptor for survival. Masuda et al. show that loss of m1G37 from the 3′ side of the tRNA anticodon renders a modified wobble nucleotide of the anticodon insufficient to decode a set of rare codons, providing a functional underpinning for the “modification circuit” between position 37 and the wobble position of the tRNA anticodon.
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25
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Brégeon D, Pecqueur L, Toubdji S, Sudol C, Lombard M, Fontecave M, de Crécy-Lagard V, Motorin Y, Helm M, Hamdane D. Dihydrouridine in the Transcriptome: New Life for This Ancient RNA Chemical Modification. ACS Chem Biol 2022; 17:1638-1657. [PMID: 35737906 DOI: 10.1021/acschembio.2c00307] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Until recently, post-transcriptional modifications of RNA were largely restricted to noncoding RNA species. However, this belief seems to have quickly dissipated with the growing number of new modifications found in mRNA that were originally thought to be primarily tRNA-specific, such as dihydrouridine. Recently, transcriptomic profiling, metabolic labeling, and proteomics have identified unexpected dihydrouridylation of mRNAs, greatly expanding the catalog of novel mRNA modifications. These data also implicated dihydrouridylation in meiotic chromosome segregation, protein translation rates, and cell proliferation. Dihydrouridylation of tRNAs and mRNAs are introduced by flavin-dependent dihydrouridine synthases. In this review, we will briefly outline the current knowledge on the distribution of dihydrouridines in the transcriptome, their chemical labeling, and highlight structural and mechanistic aspects regarding the dihydrouridine synthases enzyme family. A special emphasis on important research directions to be addressed will also be discussed. This new entry of dihydrouridine into mRNA modifications has definitely added a new layer of information that controls protein synthesis.
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Affiliation(s)
- Damien Brégeon
- IBPS, Biology of Aging and Adaptation, Sorbonne Université, Paris 75252, France
| | - Ludovic Pecqueur
- Laboratoire de Chimie des Processus Biologiques, CNRS-UMR 8229, Collège De France, Université Pierre et Marie Curie, 11 place Marcelin Berthelot, 75231 Paris, Cedex 05, France
| | - Sabrine Toubdji
- IBPS, Biology of Aging and Adaptation, Sorbonne Université, Paris 75252, France
- Laboratoire de Chimie des Processus Biologiques, CNRS-UMR 8229, Collège De France, Université Pierre et Marie Curie, 11 place Marcelin Berthelot, 75231 Paris, Cedex 05, France
| | - Claudia Sudol
- IBPS, Biology of Aging and Adaptation, Sorbonne Université, Paris 75252, France
- Laboratoire de Chimie des Processus Biologiques, CNRS-UMR 8229, Collège De France, Université Pierre et Marie Curie, 11 place Marcelin Berthelot, 75231 Paris, Cedex 05, France
| | - Murielle Lombard
- Laboratoire de Chimie des Processus Biologiques, CNRS-UMR 8229, Collège De France, Université Pierre et Marie Curie, 11 place Marcelin Berthelot, 75231 Paris, Cedex 05, France
| | - Marc Fontecave
- Laboratoire de Chimie des Processus Biologiques, CNRS-UMR 8229, Collège De France, Université Pierre et Marie Curie, 11 place Marcelin Berthelot, 75231 Paris, Cedex 05, France
| | - Valérie de Crécy-Lagard
- Department of Microbiology and Cell Science, University of Florida, Gainesville, Florida 32611, United States
- Genetics Institute, University of Florida, Gainesville, Florida 32610, United States
| | - Yuri Motorin
- Université de Lorraine, CNRS, INSERM, UMS2008/US40 IBSLor, EpiRNA-Seq Core Facility, Nancy F-54000, France
- Université de Lorraine, CNRS, UMR7365 IMoPA, Nancy F-54000, France
| | - Mark Helm
- Institut für pharmazeutische und biomedizinische Wissenschaften (IPBW), Johannes Gutenberg-Universität, Mainz 55128, Germany
| | - Djemel Hamdane
- Laboratoire de Chimie des Processus Biologiques, CNRS-UMR 8229, Collège De France, Université Pierre et Marie Curie, 11 place Marcelin Berthelot, 75231 Paris, Cedex 05, France
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26
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Sekulovski S, Trowitzsch S. Transfer RNA processing - from a structural and disease perspective. Biol Chem 2022; 403:749-763. [PMID: 35728022 DOI: 10.1515/hsz-2021-0406] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 05/24/2022] [Indexed: 01/05/2023]
Abstract
Transfer RNAs (tRNAs) are highly structured non-coding RNAs which play key roles in translation and cellular homeostasis. tRNAs are initially transcribed as precursor molecules and mature by tightly controlled, multistep processes that involve the removal of flanking and intervening sequences, over 100 base modifications, addition of non-templated nucleotides and aminoacylation. These molecular events are intertwined with the nucleocytoplasmic shuttling of tRNAs to make them available at translating ribosomes. Defects in tRNA processing are linked to the development of neurodegenerative disorders. Here, we summarize structural aspects of tRNA processing steps with a special emphasis on intron-containing tRNA splicing involving tRNA splicing endonuclease and ligase. Their role in neurological pathologies will be discussed. Identification of novel RNA substrates of the tRNA splicing machinery has uncovered functions unrelated to tRNA processing. Future structural and biochemical studies will unravel their mechanistic underpinnings and deepen our understanding of neurological diseases.
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Affiliation(s)
- Samoil Sekulovski
- Institute of Biochemistry, Biocenter, Goethe University Frankfurt, Max-von-Laue-Strasse 9, D-60438 Frankfurt/Main, Germany
| | - Simon Trowitzsch
- Institute of Biochemistry, Biocenter, Goethe University Frankfurt, Max-von-Laue-Strasse 9, D-60438 Frankfurt/Main, Germany
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27
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Wongsurawat T, Jenjaroenpun P, Wanchai V, Nookaew I. Native RNA or cDNA Sequencing for Transcriptomic Analysis: A Case Study on Saccharomyces cerevisiae. Front Bioeng Biotechnol 2022; 10:842299. [PMID: 35497361 PMCID: PMC9039254 DOI: 10.3389/fbioe.2022.842299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 03/01/2022] [Indexed: 11/13/2022] Open
Abstract
Direct sequencing of single molecules through nanopores allows for accurate quantification and full-length characterization of native RNA or complementary DNA (cDNA) without amplification. Both nanopore-based native RNA and cDNA approaches involve complex transcriptome procedures at a lower cost. However, there are several differences between the two approaches. In this study, we perform matched native RNA sequencing and cDNA sequencing to enable relevant comparisons and evaluation. Using Saccharomyces cerevisiae, a eukaryotic model organism widely used in industrial biotechnology, two different growing conditions are considered for comparison, including the poly-A messenger RNA isolated from yeast cells grown in minimum media under respirofermentative conditions supplemented with glucose (glucose growth conditions) and from cells that had shifted to ethanol as a carbon source (ethanol growth conditions). Library preparation for direct RNA sequencing is shorter than that for direct cDNA sequencing. The sequence characteristics of the two methods were different, such as sequence yields, quality score of reads, read length distribution, and mapped on reference ability of reads. However, differential gene expression analyses derived from the two approaches are comparable. The unique feature of direct RNA sequencing is RNA modification; we found that the RNA modification at the 5' end of a transcript was underestimated due to the 3' bias behavior of the direct RNA sequencing. Our comprehensive evaluation from this work could help researchers make informed choices when selecting an appropriate long-read sequencing method for understanding gene functions, pathways, and detailed functional characterization.
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Affiliation(s)
- Thidathip Wongsurawat
- Division of Bioinformatics and Data Management for Research, Research Group and Research Network Division, Research Department, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Piroon Jenjaroenpun
- Division of Bioinformatics and Data Management for Research, Research Group and Research Network Division, Research Department, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Visanu Wanchai
- Department of Biomedical Informatics, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Intawat Nookaew
- Department of Biomedical Informatics, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR, United States
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28
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Nishida Y, Ohmori S, Kakizono R, Kawai K, Namba M, Okada K, Yamagami R, Hirata A, Hori H. Required Elements in tRNA for Methylation by the Eukaryotic tRNA (Guanine- N2-) Methyltransferase (Trm11-Trm112 Complex). Int J Mol Sci 2022; 23:ijms23074046. [PMID: 35409407 PMCID: PMC8999500 DOI: 10.3390/ijms23074046] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Revised: 04/03/2022] [Accepted: 04/04/2022] [Indexed: 12/10/2022] Open
Abstract
The Saccharomyces cerevisiae Trm11 and Trm112 complex (Trm11-Trm112) methylates the 2-amino group of guanosine at position 10 in tRNA and forms N2-methylguanosine. To determine the elements required in tRNA for methylation by Trm11-Trm112, we prepared 60 tRNA transcript variants and tested them for methylation by Trm11-Trm112. The results show that the precursor tRNA is not a substrate for Trm11-Trm112. Furthermore, the CCA terminus is essential for methylation by Trm11-Trm112, and Trm11-Trm112 also only methylates tRNAs with a regular-size variable region. In addition, the G10-C25 base pair is required for methylation by Trm11-Trm112. The data also demonstrated that Trm11-Trm112 recognizes the anticodon-loop and that U38 in tRNAAla acts negatively in terms of methylation. Likewise, the U32-A38 base pair in tRNACys negatively affects methylation. The only exception in our in vitro study was tRNAValAAC1. Our experiments showed that the tRNAValAAC1 transcript was slowly methylated by Trm11-Trm112. However, position 10 in this tRNA was reported to be unmodified G. We purified tRNAValAAC1 from wild-type and trm11 gene deletion strains and confirmed that a portion of tRNAValAAC1 is methylated by Trm11-Trm112 in S. cerevisiae. Thus, our study explains the m2G10 modification pattern of all S. cerevisiae class I tRNAs and elucidates the Trm11-Trm112 binding sites.
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29
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Khalique A, Mattijssen S, Maraia RJ. A versatile tRNA modification-sensitive northern blot method with enhanced performance. RNA (NEW YORK, N.Y.) 2022; 28:418-432. [PMID: 34930808 PMCID: PMC8848930 DOI: 10.1261/rna.078929.121] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 12/01/2021] [Indexed: 06/14/2023]
Abstract
The 22 mitochondrial and ∼45 cytosolic tRNAs in human cells contain several dozen different post-transcriptional modified nucleotides such that each carries a unique constellation that complements its function. Many tRNA modifications are linked to altered gene expression, and deficiencies due to mutations in tRNA modification enzymes (TMEs) are responsible for numerous diseases. Easily accessible methods to detect tRNA hypomodifications can facilitate progress in advancing such molecular studies. Our laboratory developed a northern blot method that can quantify relative levels of base modifications on multiple specific tRNAs ∼10 yr ago, which has been used to characterize four different TME deficiencies and is likely further extendable. The assay method depends on differential annealing efficiency of a DNA-oligo probe to the modified versus unmodified tRNA. The signal of this probe is then normalized by a second probe elsewhere on the same tRNA. This positive hybridization in the absence of modification (PHAM) assay has proven useful for i6A37, t6A37, m3C32, and m2,2G26 in multiple laboratories. Yet, over the years we have observed idiosyncratic inconsistency and variability in the assay. Here we document these for some tRNAs and probes and illustrate principles and practices for improved reliability and uniformity in performance. We provide an overview of the method and illustrate benefits of the improved conditions. This is followed by data that demonstrate quantitative validation of PHAM using a TME deletion control, and that nearby modifications can falsely alter the calculated apparent modification efficiency. Finally, we include a calculator tool for matching probe and hybridization conditions.
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Affiliation(s)
- Abdul Khalique
- Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Sandy Mattijssen
- Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Richard J Maraia
- Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA
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30
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Bohnsack KE, Kleiber N, Lemus-Diaz N, Bohnsack MT. Roles and dynamics of 3-methylcytidine in cellular RNAs. Trends Biochem Sci 2022; 47:596-608. [DOI: 10.1016/j.tibs.2022.03.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 02/14/2022] [Accepted: 03/02/2022] [Indexed: 01/02/2023]
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31
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Biedenbänder T, de Jesus V, Schmidt-Dengler M, Helm M, Corzilius B, Fürtig B. RNA modifications stabilize the tertiary structure of tRNAfMet by locally increasing conformational dynamics. Nucleic Acids Res 2022; 50:2334-2349. [PMID: 35137185 PMCID: PMC8887418 DOI: 10.1093/nar/gkac040] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 12/29/2021] [Accepted: 01/14/2022] [Indexed: 11/12/2022] Open
Abstract
A plethora of modified nucleotides extends the chemical and conformational space for natural occurring RNAs. tRNAs constitute the class of RNAs with the highest modification rate. The extensive modification modulates their overall stability, the fidelity and efficiency of translation. However, the impact of nucleotide modifications on the local structural dynamics is not well characterized. Here we show that the incorporation of the modified nucleotides in tRNAfMet from Escherichia coli leads to an increase in the local conformational dynamics, ultimately resulting in the stabilization of the overall tertiary structure. Through analysis of the local dynamics by NMR spectroscopic methods we find that, although the overall thermal stability of the tRNA is higher for the modified molecule, the conformational fluctuations on the local level are increased in comparison to an unmodified tRNA. In consequence, the melting of individual base pairs in the unmodified tRNA is determined by high entropic penalties compared to the modified. Further, we find that the modifications lead to a stabilization of long-range interactions harmonizing the stability of the tRNA's secondary and tertiary structure. Our results demonstrate that the increase in chemical space through introduction of modifications enables the population of otherwise inaccessible conformational substates.
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Affiliation(s)
- Thomas Biedenbänder
- Institute for Organic Chemistry and Chemical Biology, Center for Biomolecular Magnetic Resonance (BMRZ), Johann Wolfgang Goethe-Universität, Frankfurt am Main 60438, Germany.,Institute of Chemistry and Department Life, Light & Matter, University of Rostock, Rostock 18059, Germany
| | - Vanessa de Jesus
- Institute for Organic Chemistry and Chemical Biology, Center for Biomolecular Magnetic Resonance (BMRZ), Johann Wolfgang Goethe-Universität, Frankfurt am Main 60438, Germany
| | - Martina Schmidt-Dengler
- Institut für pharmazeutische und biomedizinische Wissenschaften (IPBW), Johannes Gutenberg-Universität, Mainz 55128, Germany
| | - Mark Helm
- Institut für pharmazeutische und biomedizinische Wissenschaften (IPBW), Johannes Gutenberg-Universität, Mainz 55128, Germany
| | - Björn Corzilius
- Institute of Chemistry and Department Life, Light & Matter, University of Rostock, Rostock 18059, Germany
| | - Boris Fürtig
- Institute for Organic Chemistry and Chemical Biology, Center for Biomolecular Magnetic Resonance (BMRZ), Johann Wolfgang Goethe-Universität, Frankfurt am Main 60438, Germany
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32
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Kleiber N, Lemus-Diaz N, Stiller C, Heinrichs M, Mai MMQ, Hackert P, Richter-Dennerlein R, Höbartner C, Bohnsack KE, Bohnsack MT. The RNA methyltransferase METTL8 installs m 3C 32 in mitochondrial tRNAs Thr/Ser(UCN) to optimise tRNA structure and mitochondrial translation. Nat Commun 2022; 13:209. [PMID: 35017528 PMCID: PMC8752778 DOI: 10.1038/s41467-021-27905-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 12/14/2021] [Indexed: 12/30/2022] Open
Abstract
Modified nucleotides in tRNAs are important determinants of folding, structure and function. Here we identify METTL8 as a mitochondrial matrix protein and active RNA methyltransferase responsible for installing m3C32 in the human mitochondrial (mt-)tRNAThr and mt-tRNASer(UCN). METTL8 crosslinks to the anticodon stem loop (ASL) of many mt-tRNAs in cells, raising the question of how methylation target specificity is achieved. Dissection of mt-tRNA recognition elements revealed U34G35 and t6A37/(ms2)i6A37, present concomitantly only in the ASLs of the two substrate mt-tRNAs, as key determinants for METTL8-mediated methylation of C32. Several lines of evidence demonstrate the influence of U34, G35, and the m3C32 and t6A37/(ms2)i6A37 modifications in mt-tRNAThr/Ser(UCN) on the structure of these mt-tRNAs. Although mt-tRNAThr/Ser(UCN) lacking METTL8-mediated m3C32 are efficiently aminoacylated and associate with mitochondrial ribosomes, mitochondrial translation is mildly impaired by lack of METTL8. Together these results define the cellular targets of METTL8 and shed new light on the role of m3C32 within mt-tRNAs.
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MESH Headings
- Anticodon/chemistry
- Anticodon/metabolism
- Base Pairing
- Cytosine/metabolism
- Gene Expression Regulation
- HEK293 Cells
- Humans
- Methylation
- Methyltransferases/genetics
- Methyltransferases/metabolism
- Mitochondria/genetics
- Mitochondria/metabolism
- Nucleic Acid Conformation
- Protein Binding
- Protein Biosynthesis
- RNA, Mitochondrial/chemistry
- RNA, Mitochondrial/genetics
- RNA, Mitochondrial/metabolism
- RNA, Transfer, Ser/chemistry
- RNA, Transfer, Ser/genetics
- RNA, Transfer, Ser/metabolism
- RNA, Transfer, Thr/chemistry
- RNA, Transfer, Thr/genetics
- RNA, Transfer, Thr/metabolism
- Signal Transduction
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Affiliation(s)
- Nicole Kleiber
- Department of Molecular Biology, University Medical Centre Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
| | - Nicolas Lemus-Diaz
- Department of Molecular Biology, University Medical Centre Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
| | - Carina Stiller
- Institute of Organic Chemistry, Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Marleen Heinrichs
- Department of Cellular Biochemistry, University Medical Centre Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
| | - Mandy Mong-Quyen Mai
- Department of Cellular Biochemistry, University Medical Centre Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
| | - Philipp Hackert
- Department of Molecular Biology, University Medical Centre Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
| | - Ricarda Richter-Dennerlein
- Department of Cellular Biochemistry, University Medical Centre Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
- Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), Göttingen, Germany
| | - Claudia Höbartner
- Institute of Organic Chemistry, Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Katherine E Bohnsack
- Department of Molecular Biology, University Medical Centre Göttingen, Humboldtallee 23, 37073, Göttingen, Germany.
| | - Markus T Bohnsack
- Department of Molecular Biology, University Medical Centre Göttingen, Humboldtallee 23, 37073, Göttingen, Germany.
- Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), Göttingen, Germany.
- Göttingen Center for Molecular Biosciences, Georg-August University Göttingen, Justus-von-Liebig-Weg 11, Göttingen, 37077, Germany.
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33
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Motorin Y, Helm M. RNA nucleotide methylation: 2021 update. WILEY INTERDISCIPLINARY REVIEWS. RNA 2022; 13:e1691. [PMID: 34913259 DOI: 10.1002/wrna.1691] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Revised: 07/22/2021] [Accepted: 07/22/2021] [Indexed: 12/14/2022]
Abstract
Among RNA modifications, transfer of methylgroups from the typical cofactor S-adenosyl-l-methionine by methyltransferases (MTases) to RNA is by far the most common reaction. Since our last review about a decade ago, the field has witnessed the re-emergence of mRNA methylation as an important mechanism in gene regulation. Attention has then spread to many other RNA species; all being included into the newly coined concept of the "epitranscriptome." The focus moved from prokaryotes and single cell eukaryotes as model organisms to higher eukaryotes, in particular to mammals. The perception of the field has dramatically changed over the past decade. A previous lack of phenotypes in knockouts in single cell organisms has been replaced by the apparition of MTases in numerous disease models and clinical investigations. Major driving forces of the field include methylation mapping techniques, as well as the characterization of the various MTases, termed "writers." The latter term has spilled over from DNA modification in the neighboring epigenetics field, along with the designations "readers," applied to mediators of biological effects upon specific binding to a methylated RNA. Furthermore "eraser" enzymes effect the newly discovered oxidative removal of methylgroups. A sense of reversibility and dynamics has replaced the older perception of RNA modification as a concrete-cast, irreversible part of RNA maturation. A related concept concerns incompletely methylated residues, which, through permutation of each site, lead to inhomogeneous populations of numerous modivariants. This review recapitulates the major developments of the past decade outlined above, and attempts a prediction of upcoming trends. This article is categorized under: RNA Processing > RNA Editing and Modification.
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Affiliation(s)
- Yuri Motorin
- Université de Lorraine, CNRS, INSERM, UMS2008/US40 IBSLor, EpiRNA-Seq Core Facility, Nancy, France.,Université de Lorraine, CNRS, UMR7365 IMoPA, Nancy, France
| | - Mark Helm
- Institute of Pharmaceutical and Biomedical Sciences, Johannes Gutenberg-Universität, Mainz, Germany
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34
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Huang ZX, Li J, Xiong QP, Li H, Wang ED, Liu RJ. Position 34 of tRNA is a discriminative element for m5C38 modification by human DNMT2. Nucleic Acids Res 2021; 49:13045-13061. [PMID: 34871455 PMCID: PMC8682788 DOI: 10.1093/nar/gkab1148] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 10/05/2021] [Accepted: 11/03/2021] [Indexed: 12/05/2022] Open
Abstract
Dnmt2, a member of the DNA methyltransferase superfamily, catalyzes the formation of 5-methylcytosine at position 38 in the anticodon loop of tRNAs. Dnmt2 regulates many cellular biological processes, especially the production of tRNA-derived fragments and intergenerational transmission of paternal metabolic disorders to offspring. Moreover, Dnmt2 is closely related to human cancers. The tRNA substrates of mammalian Dnmt2s are mainly detected using bisulfite sequencing; however, we lack supporting biochemical data concerning their substrate specificity or recognition mechanism. Here, we deciphered the tRNA substrates of human DNMT2 (hDNMT2) as tRNAAsp(GUC), tRNAGly(GCC) and tRNAVal(AAC). Intriguingly, for tRNAAsp(GUC) and tRNAGly(GCC), G34 is the discriminator element; whereas for tRNAVal(AAC), the inosine modification at position 34 (I34), which is formed by the ADAT2/3 complex, is the prerequisite for hDNMT2 recognition. We showed that the C32U33(G/I)34N35 (C/U)36A37C38 motif in the anticodon loop, U11:A24 in the D stem, and the correct size of the variable loop are required for Dnmt2 recognition of substrate tRNAs. Furthermore, mammalian Dnmt2s possess a conserved tRNA recognition mechanism.
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MESH Headings
- 5-Methylcytosine/metabolism
- Adenosine Deaminase/genetics
- Adenosine Deaminase/metabolism
- Animals
- Anticodon/genetics
- Anticodon/metabolism
- Base Sequence
- DNA (Cytosine-5-)-Methyltransferases/chemistry
- DNA (Cytosine-5-)-Methyltransferases/genetics
- DNA (Cytosine-5-)-Methyltransferases/metabolism
- HEK293 Cells
- HeLa Cells
- Humans
- Inosine/metabolism
- Mice
- Models, Molecular
- NIH 3T3 Cells
- Nucleic Acid Conformation
- Protein Binding
- RNA, Transfer/chemistry
- RNA, Transfer/genetics
- RNA, Transfer/metabolism
- RNA, Transfer, Asp/chemistry
- RNA, Transfer, Asp/genetics
- RNA, Transfer, Asp/metabolism
- RNA, Transfer, Gly/chemistry
- RNA, Transfer, Gly/genetics
- RNA, Transfer, Gly/metabolism
- RNA, Transfer, Val/chemistry
- RNA, Transfer, Val/genetics
- RNA, Transfer, Val/metabolism
- RNA-Binding Proteins/genetics
- RNA-Binding Proteins/metabolism
- Substrate Specificity
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Affiliation(s)
- Zhi-Xuan Huang
- State Key Laboratory of Molecular Biology, Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China; University of Chinese Academy of Sciences, Beijing 100039, China
- School of Life Science and Technology, ShanghaiTech University, 393 Middle Hua Xia Road, Shanghai 201210, China
| | - Jing Li
- School of Life Science and Technology, ShanghaiTech University, 393 Middle Hua Xia Road, Shanghai 201210, China
| | - Qing-Ping Xiong
- State Key Laboratory of Molecular Biology, Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China; University of Chinese Academy of Sciences, Beijing 100039, China
| | - Hao Li
- School of Life Science and Technology, ShanghaiTech University, 393 Middle Hua Xia Road, Shanghai 201210, China
| | - En-Duo Wang
- State Key Laboratory of Molecular Biology, Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China; University of Chinese Academy of Sciences, Beijing 100039, China
- School of Life Science and Technology, ShanghaiTech University, 393 Middle Hua Xia Road, Shanghai 201210, China
| | - Ru-Juan Liu
- School of Life Science and Technology, ShanghaiTech University, 393 Middle Hua Xia Road, Shanghai 201210, China
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35
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tRNA modifications and their potential roles in pancreatic cancer. Arch Biochem Biophys 2021; 714:109083. [PMID: 34785212 DOI: 10.1016/j.abb.2021.109083] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Revised: 11/05/2021] [Accepted: 11/06/2021] [Indexed: 12/23/2022]
Abstract
Since the breakthrough discovery of N6-methyladenosine (m6A), the field of RNA epitranscriptomics has attracted increasing interest in the biological sciences. Transfer RNAs (tRNAs) are extensively modified, and various modifications play a crucial role in the formation and stability of tRNA, which is universally required for accurate and efficient functioning of tRNA. Abnormal tRNA modification can lead to tRNA degradation or specific cleavage of tRNA into fragmented derivatives, thus affecting the translation process and frequently accompanying a variety of human diseases. Increasing evidence suggests that tRNA modification pathways are also misregulated in human cancers. In this review, we summarize tRNA modifications and their biological functions, describe the type and frequency of tRNA modification alterations in cancer, and highlight variations in tRNA-modifying enzymes and the multiple functions that they regulate in different types of cancers. Furthermore, the current implications and the potential role of tRNA modifications in the progression of pancreatic cancer are discussed. Collectively, this review describes recent advances in tRNA modification in cancers and its potential significance in pancreatic cancer. Further study of the mechanism of tRNA modifications in pancreatic cancer may provide possibilities for therapies targeting enzymes responsible for regulating tRNA modifications in pancreatic cancer.
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36
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Balancing of mitochondrial translation through METTL8-mediated m 3C modification of mitochondrial tRNAs. Mol Cell 2021; 81:4810-4825.e12. [PMID: 34774131 DOI: 10.1016/j.molcel.2021.10.018] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 08/19/2021] [Accepted: 10/18/2021] [Indexed: 02/08/2023]
Abstract
Mitochondria contain a specific translation machinery for the synthesis of mitochondria-encoded respiratory chain components. Mitochondrial tRNAs (mt-tRNAs) are also generated from the mitochondrial DNA and, similar to their cytoplasmic counterparts, are post-transcriptionally modified. Here, we find that the RNA methyltransferase METTL8 is a mitochondrial protein that facilitates 3-methyl-cytidine (m3C) methylation at position C32 of the mt-tRNASer(UCN) and mt-tRNAThr. METTL8 knockout cells show a reduction in respiratory chain activity, whereas overexpression increases activity. In pancreatic cancer, METTL8 levels are high, which correlates with lower patient survival and an enhanced respiratory chain activity. Mitochondrial ribosome profiling uncovered mitoribosome stalling on mt-tRNASer(UCN)- and mt-tRNAThr-dependent codons. Further analysis of the respiratory chain complexes using mass spectrometry revealed reduced incorporation of the mitochondrially encoded proteins ND6 and ND1 into complex I. The well-balanced translation of mt-tRNASer(UCN)- and mt-tRNAThr-dependent codons through METTL8-mediated m3C32 methylation might, therefore, facilitate the optimal composition and function of the mitochondrial respiratory chain.
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37
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Zhou JB, Wang ED, Zhou XL. Modifications of the human tRNA anticodon loop and their associations with genetic diseases. Cell Mol Life Sci 2021; 78:7087-7105. [PMID: 34605973 PMCID: PMC11071707 DOI: 10.1007/s00018-021-03948-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 09/07/2021] [Accepted: 09/21/2021] [Indexed: 12/11/2022]
Abstract
Transfer RNAs (tRNAs) harbor the most diverse posttranscriptional modifications. Among such modifications, those in the anticodon loop, either on nucleosides or base groups, compose over half of the identified posttranscriptional modifications. The derivatives of modified nucleotides and the crosstalk of different chemical modifications further add to the structural and functional complexity of tRNAs. These modifications play critical roles in maintaining anticodon loop conformation, wobble base pairing, efficient aminoacylation, and translation speed and fidelity as well as mediating various responses to different stress conditions. Posttranscriptional modifications of tRNA are catalyzed mainly by enzymes and/or cofactors encoded by nuclear genes, whose mutations are firmly connected with diverse human diseases involving genetic nervous system disorders and/or the onset of multisystem failure. In this review, we summarize recent studies about the mechanisms of tRNA modifications occurring at tRNA anticodon loops. In addition, the pathogenesis of related disease-causing mutations at these genes is briefly described.
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Affiliation(s)
- Jing-Bo Zhou
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai, 200031, China
| | - En-Duo Wang
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai, 200031, China.
- School of Life Science and Technology, ShanghaiTech University, 93 Middle Huaxia Road, Shanghai, 201210, China.
| | - Xiao-Long Zhou
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai, 200031, China.
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38
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Li H, Zhu D, Wu J, Ma Y, Cai C, Chen Y, Qin M, Dai H. New substrates and determinants for tRNA recognition of RNA methyltransferase DNMT2/TRDMT1. RNA Biol 2021; 18:2531-2545. [PMID: 34110975 PMCID: PMC8632113 DOI: 10.1080/15476286.2021.1930756] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 04/16/2021] [Accepted: 05/12/2021] [Indexed: 02/07/2023] Open
Abstract
Methylation is a common post-transcriptional modification of tRNAs, particularly in the anticodon loop region. The cytosine 38 (C38) in tRNAs, such as tRNAAsp-GUC, tRNAGly-GCC, tRNAVal-AAC, and tRNAGlu-CUC, can be methylated by human DNMT2/TRDMT1 and some homologs found in bacteria, plants, and animals. However, the substrate properties and recognition mechanism of DNMT2/TRDMT1 remain to be explored. Here, taking into consideration common features of the four known substrate tRNAs, we investigated methylation activities of DNMT2/TRDMT1 on the tRNAGly-GCC truncation and point mutants, and conformational changes of mutants. The results demonstrated that human DNMT2/TRDMT1 preferred substrate tRNAGly-GCC in vitro. L-shaped conformation of classical tRNA could be favourable for DNMT2/TRDMT1 activity. The complete sequence and structure of tRNA were dispensable for DNMT2/TRDMT1 activity, whereas T-arm was indispensable to this activity. G19, U20, and A21 in D-loop were identified as the important bases for DNMT2/TRDMT1 activity, while G53, C56, A58, and C61 in T-loop were found as the critical bases. The conserved CUXXCAC sequence in the anticodon loop was confirmed to be the most critical determinant, and it could stabilize C38-flipping to promote C38 methylation. Based on these tRNA properties, new substrates, tRNAVal-CAC and tRNAGln-CUG, were discovered in vitro. Moreover, a single nucleotide substitute, U32C, could convert non-substrate tRNAAla-AGC into a substrate for DNMT2/TRDMT1. Altogether, our findings imply that DNMT2/TRDMT1 relies on a delicate network involving both the primary sequence and tertiary structure of tRNA for substrate recognition.
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Affiliation(s)
- Huari Li
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Daiyun Zhu
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Jian Wu
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Yunfei Ma
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Chao Cai
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Yong Chen
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Mian Qin
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Hanchuan Dai
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China
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39
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Beenstock J, Sicheri F. The structural and functional workings of KEOPS. Nucleic Acids Res 2021; 49:10818-10834. [PMID: 34614169 PMCID: PMC8565320 DOI: 10.1093/nar/gkab865] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 09/09/2021] [Accepted: 10/04/2021] [Indexed: 11/14/2022] Open
Abstract
KEOPS (Kinase, Endopeptidase and Other Proteins of Small size) is a five-subunit protein complex that is highly conserved in eukaryotes and archaea and is essential for the fitness of cells and for animal development. In humans, mutations in KEOPS genes underlie Galloway-Mowat syndrome, which manifests in severe microcephaly and renal dysfunction that lead to childhood death. The Kae1 subunit of KEOPS catalyzes the universal and essential tRNA modification N6-threonylcarbamoyl adenosine (t6A), while the auxiliary subunits Cgi121, the kinase/ATPase Bud32, Pcc1 and Gon7 play a supporting role. Kae1 orthologs are also present in bacteria and mitochondria but function in distinct complexes with proteins that are not related in structure or function to the auxiliary subunits of KEOPS. Over the past 15 years since its discovery, extensive study in the KEOPS field has provided many answers towards understanding the roles that KEOPS plays in cells and in human disease and how KEOPS carries out these functions. In this review, we provide an overview into recent advances in the study of KEOPS and illuminate exciting future directions.
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Affiliation(s)
- Jonah Beenstock
- The Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, M5G 1X5, Canada
| | - Frank Sicheri
- The Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, M5G 1X5, Canada.,Department of Molecular Genetics, University of Toronto, Ontario, M5S 1A8, Canada.,Department of Biochemistry, University of Toronto, Ontario, M5S 1A8, Canada
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40
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Li J, Zhu WY, Yang WQ, Li CT, Liu RJ. The occurrence order and cross-talk of different tRNA modifications. SCIENCE CHINA. LIFE SCIENCES 2021; 64:1423-1436. [PMID: 33881742 DOI: 10.1007/s11427-020-1906-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Accepted: 03/02/2021] [Indexed: 06/12/2023]
Abstract
Chemical modifications expand the composition of RNA molecules from four standard nucleosides to over 160 modified nucleosides, which greatly increase the complexity and utility of RNAs. Transfer RNAs (tRNAs) are the most heavily modified cellular RNA molecules and contain the largest variety of modifications. Modification of tRNAs is pivotal for protein synthesis and also precisely regulates the noncanonical functions of tRNAs. Defects in tRNA modifications lead to numerous human diseases. Up to now, more than 100 types of modifications have been found in tRNAs. Intriguingly, some modifications occur widely on all tRNAs, while others only occur on a subgroup of tRNAs or even only a specific tRNA. The modification frequency of each tRNA is approximately 7% to 25%, with 5-20 modification sites present on each tRNA. The occurrence and modulation of tRNA modifications are specifically noticeable as plenty of interplays among different sites and modifications have been discovered. In particular, tRNA modifications are responsive to environmental changes, indicating their dynamic and highly organized nature. In this review, we summarized the known occurrence order, cross-talk, and cooperativity of tRNA modifications.
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Affiliation(s)
- Jing Li
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Wen-Yu Zhu
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Wen-Qing Yang
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Cai-Tao Li
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Ru-Juan Liu
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China.
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41
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Mao XL, Li ZH, Huang MH, Wang JT, Zhou JB, Li QR, Xu H, Wang XJ, Zhou XL. Mutually exclusive substrate selection strategy by human m3C RNA transferases METTL2A and METTL6. Nucleic Acids Res 2021; 49:8309-8323. [PMID: 34268557 PMCID: PMC8373065 DOI: 10.1093/nar/gkab603] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 06/27/2021] [Accepted: 07/01/2021] [Indexed: 12/28/2022] Open
Abstract
tRNAs harbor the most diverse posttranscriptional modifications. The 3-methylcytidine (m3C) is widely distributed at position C32 (m3C32) of eukaryotic tRNAThr and tRNASer species. m3C32 is decorated by the single methyltransferase Trm140 in budding yeasts; however, two (Trm140 and Trm141 in fission yeasts) or three enzymes (METTL2A, METTL2B and METTL6 in mammals) are involved in its biogenesis. The rationale for the existence of multiple m3C32 methyltransferases and their substrate discrimination mechanism is hitherto unknown. Here, we revealed that both METTL2A and METTL2B are expressed in vivo. We purified human METTL2A, METTL2B, and METTL6 to high homogeneity. We successfully reconstituted m3C32 modification activity for tRNAThr by METT2A and for tRNASer(GCU) by METTL6, assisted by seryl-tRNA synthetase (SerRS) in vitro. Compared with METTL2A, METTL2B exhibited dramatically lower activity in vitro. Both G35 and t6A at position 37 (t6A37) are necessary but insufficient prerequisites for tRNAThr m3C32 formation, while the anticodon loop and the long variable arm, but not t6A37, are key determinants for tRNASer(GCU) m3C32 biogenesis, likely being recognized synergistically by METTL6 and SerRS, respectively. Finally, we proposed a mutually exclusive substrate selection model to ensure correct discrimination among multiple tRNAs by multiple m3C32 methyltransferases.
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Affiliation(s)
- Xue-Ling Mao
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Zi-Han Li
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Meng-Han Huang
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Jin-Tao Wang
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Jing-Bo Zhou
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Qing-Run Li
- CAS Key Laboratory of Systems Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Hong Xu
- Shanghai Key Laboratory of Embryo Original Diseases, the International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, 910 Heng Shan Road, Shanghai 200030, China
| | - Xi-Jin Wang
- Department of Neurology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, 1665 Kong Jiang Road, Shanghai 200092, China
| | - Xiao-Long Zhou
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
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42
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Partially modified tRNAs for the study of tRNA maturation and function. Methods Enzymol 2021; 658:225-250. [PMID: 34517948 DOI: 10.1016/bs.mie.2021.06.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Transfer RNA (tRNA) is the most highly and diversely modified class of RNA in all domains of life. However, we still have only a limited understanding of the concerted action of the many enzymes that modify tRNA during tRNA maturation and the synergistic functions of tRNA modifications for protein synthesis. Here, we describe the preparation of in vitro transcribed tRNAs with a partial set of defined modifications and the use of partially modified tRNAs in biochemical assays. By comparing the affinity and activity of tRNA modification enzymes for partially modified and unmodified tRNAs, we gain insight into the preferred pathways of tRNA maturation. Additionally, partially modified tRNAs will be highly useful to investigate the importance of tRNA modifications for tRNA function during translation including the interaction with aminoacyl-tRNA synthases, translation factors and the ribosome. Thereby, the methods described here lay the foundation for understanding the mechanistic function of tRNA modifications.
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43
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Levi O, Arava YS. RNA modifications as a common denominator between tRNA and mRNA. Curr Genet 2021; 67:545-551. [PMID: 33683402 DOI: 10.1007/s00294-021-01168-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 02/23/2021] [Accepted: 02/25/2021] [Indexed: 12/27/2022]
Abstract
Recent studies underscore RNA modifications as a novel mechanism to coordinate expression and function of different genes. While modifications on the sugar or base moieties of tRNA are well known, their roles in mRNA regulation are only starting to emerge. Interestingly, some modifications are present in both tRNA and mRNA, and here we discuss the functional significance of these common features. We describe key modifications that are present in both RNA types, elaborate on proteins that interact with them, and indicate recent works that identify roles in communicating tRNA processes and mRNA regulation. We propose that as tools are developed, the shortlist of features that are common between types of RNA will greatly expand and proteins that interact with them will be identified. In conclusion, the presence of the same modification in both RNA types provides an intersect between tRNA processes and mRNA regulation and implies a novel mechanism for connecting diverse cellular processes.
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Affiliation(s)
- Ofri Levi
- Faculty of Biology, Technion-Israel Institute of Technology, 3200003, Haifa, Israel
| | - Yoav S Arava
- Faculty of Biology, Technion-Israel Institute of Technology, 3200003, Haifa, Israel.
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44
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The expanding world of tRNA modifications and their disease relevance. Nat Rev Mol Cell Biol 2021; 22:375-392. [PMID: 33658722 DOI: 10.1038/s41580-021-00342-0] [Citation(s) in RCA: 261] [Impact Index Per Article: 87.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/26/2021] [Indexed: 02/08/2023]
Abstract
Transfer RNA (tRNA) is an adapter molecule that links a specific codon in mRNA with its corresponding amino acid during protein synthesis. tRNAs are enzymatically modified post-transcriptionally. A wide variety of tRNA modifications are found in the tRNA anticodon, which are crucial for precise codon recognition and reading frame maintenance, thereby ensuring accurate and efficient protein synthesis. In addition, tRNA-body regions are also frequently modified and thus stabilized in the cell. Over the past two decades, 16 novel tRNA modifications were discovered in various organisms, and the chemical space of tRNA modification continues to expand. Recent studies have revealed that tRNA modifications can be dynamically altered in response to levels of cellular metabolites and environmental stresses. Importantly, we now understand that deficiencies in tRNA modification can have pathological consequences, which are termed 'RNA modopathies'. Dysregulation of tRNA modification is involved in mitochondrial diseases, neurological disorders and cancer.
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45
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Yoluç Y, Ammann G, Barraud P, Jora M, Limbach PA, Motorin Y, Marchand V, Tisné C, Borland K, Kellner S. Instrumental analysis of RNA modifications. Crit Rev Biochem Mol Biol 2021; 56:178-204. [PMID: 33618598 DOI: 10.1080/10409238.2021.1887807] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Organisms from all domains of life invest a substantial amount of energy for the introduction of RNA modifications into nearly all transcripts studied to date. Instrumental analysis of RNA can focus on the modified residues and reveal the function of these epitranscriptomic marks. Here, we will review recent advances and breakthroughs achieved by NMR spectroscopy, sequencing, and mass spectrometry of the epitranscriptome.
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Affiliation(s)
- Yasemin Yoluç
- Department of Chemistry, Ludwig Maximilians University, Munich, Germany
| | - Gregor Ammann
- Department of Chemistry, Ludwig Maximilians University, Munich, Germany
| | - Pierre Barraud
- Expression génétique microbienne, UMR 8261, CNRS, Institut de biologie physico-chimique, IBPC, Université de Paris, Paris, France
| | - Manasses Jora
- Department of Chemistry, University of Cincinnati, Cincinnati, OH, USA
| | - Patrick A Limbach
- Department of Chemistry, University of Cincinnati, Cincinnati, OH, USA
| | - Yuri Motorin
- Université de Lorraine, CNRS, UMR7365 IMoPA, Nancy, France
| | - Virginie Marchand
- Université de Lorraine, CNRS, INSERM, Epitranscriptomics and RNA Sequencing Core facility, UM S2008, IBSLor, Nancy, France
| | - Carine Tisné
- Expression génétique microbienne, UMR 8261, CNRS, Institut de biologie physico-chimique, IBPC, Université de Paris, Paris, France
| | - Kayla Borland
- Department of Chemistry, Ludwig Maximilians University, Munich, Germany
| | - Stefanie Kellner
- Department of Chemistry, Ludwig Maximilians University, Munich, Germany.,Institute of Pharmaceutical Chemistry, Goethe-University, Frankfurt, Germany
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46
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Porat J, Kothe U, Bayfield MA. Revisiting tRNA chaperones: New players in an ancient game. RNA (NEW YORK, N.Y.) 2021; 27:rna.078428.120. [PMID: 33593999 PMCID: PMC8051267 DOI: 10.1261/rna.078428.120] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 02/10/2021] [Indexed: 05/03/2023]
Abstract
tRNAs undergo an extensive maturation process including post-transcriptional modifications that influence secondary and tertiary interactions. Precursor and mature tRNAs lacking key modifications are often recognized as aberrant and subsequently targeted for decay, illustrating the importance of modifications in promoting structural integrity. tRNAs also rely on tRNA chaperones to promote the folding of misfolded substrates into functional conformations. The best characterized tRNA chaperone is the La protein, which interacts with nascent RNA polymerase III transcripts to promote folding and offers protection from exonucleases. More recently, certain tRNA modification enzymes have also been demonstrated to possess tRNA folding activity distinct from their catalytic activity, suggesting that they may act as tRNA chaperones. In this review, we will discuss pioneering studies relating post-transcriptional modification to tRNA stability and decay pathways, present recent advances into the mechanism by which the RNA chaperone La assists pre-tRNA maturation, and summarize emerging research directions aimed at characterizing modification enzymes as tRNA chaperones. Together, these findings shed light on the importance of tRNA folding and how tRNA chaperones, in particular, increase the fraction of nascent pre-tRNAs that adopt a folded, functional conformation.
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47
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Post-Transcriptional Modifications of Conserved Nucleotides in the T-Loop of tRNA: A Tale of Functional Convergent Evolution. Genes (Basel) 2021; 12:genes12020140. [PMID: 33499018 PMCID: PMC7912444 DOI: 10.3390/genes12020140] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/18/2021] [Accepted: 01/20/2021] [Indexed: 12/30/2022] Open
Abstract
The high conservation of nucleotides of the T-loop, including their chemical identity, are hallmarks of tRNAs from organisms belonging to the three Domains of Life. These structural characteristics allow the T-loop to adopt a peculiar intraloop conformation able to interact specifically with other conserved residues of the D-loop, which ultimately folds the mature tRNA in a unique functional canonical L-shaped architecture. Paradoxically, despite the high conservation of modified nucleotides in the T-loop, enzymes catalyzing their formation depend mostly on the considered organism, attesting for an independent but convergent evolution of the post-transcriptional modification processes. The driving force behind this is the preservation of a native conformation of the tRNA elbow that underlies the various interactions of tRNA molecules with different cellular components.
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Shetty S, Varshney U. Regulation of translation by one-carbon metabolism in bacteria and eukaryotic organelles. J Biol Chem 2021; 296:100088. [PMID: 33199376 PMCID: PMC7949028 DOI: 10.1074/jbc.rev120.011985] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 11/15/2020] [Accepted: 11/16/2020] [Indexed: 12/20/2022] Open
Abstract
Protein synthesis is an energetically costly cellular activity. It is therefore important that the process of mRNA translation remains in excellent synchrony with cellular metabolism and its energy reserves. Unregulated translation could lead to the production of incomplete, mistranslated, or misfolded proteins, squandering the energy needed for cellular sustenance and causing cytotoxicity. One-carbon metabolism (OCM), an integral part of cellular intermediary metabolism, produces a number of one-carbon unit intermediates (formyl, methylene, methenyl, methyl). These OCM intermediates are required for the production of amino acids such as methionine and other biomolecules such as purines, thymidylate, and redox regulators. In this review, we discuss how OCM impacts the translation apparatus (composed of ribosome, tRNA, mRNA, and translation factors) and regulates crucial steps in protein synthesis. More specifically, we address how the OCM metabolites regulate the fidelity and rate of translation initiation in bacteria and eukaryotic organelles such as mitochondria. Modulation of the fidelity of translation initiation by OCM opens new avenues to understand alternative translation mechanisms involved in stress tolerance and drug resistance.
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Affiliation(s)
- Sunil Shetty
- Biozentrum, University of Basel, Basel, Switzerland
| | - Umesh Varshney
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India; Jawaharlal Nehru Centre for Advanced Scientific Studies, Jakkur, Bangalore, India.
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A substrate binding model for the KEOPS tRNA modifying complex. Nat Commun 2020; 11:6233. [PMID: 33277478 PMCID: PMC7718258 DOI: 10.1038/s41467-020-19990-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 11/02/2020] [Indexed: 11/09/2022] Open
Abstract
The KEOPS complex, which is conserved across archaea and eukaryotes, is composed of four core subunits; Pcc1, Kae1, Bud32 and Cgi121. KEOPS is crucial for the fitness of all organisms examined. In humans, pathogenic mutations in KEOPS genes lead to Galloway-Mowat syndrome, an autosomal-recessive disease causing childhood lethality. Kae1 catalyzes the universal and essential tRNA modification N6-threonylcarbamoyl adenosine, but the precise roles of all other KEOPS subunits remain an enigma. Here we show using structure-guided studies that Cgi121 recruits tRNA to KEOPS by binding to its 3' CCA tail. A composite model of KEOPS bound to tRNA reveals that all KEOPS subunits form an extended tRNA-binding surface that we have validated in vitro and in vivo to mediate the interaction with the tRNA substrate and its modification. These findings provide a framework for understanding the inner workings of KEOPS and delineate why all KEOPS subunits are essential.
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Adami R, Bottai D. S-adenosylmethionine tRNA modification: unexpected/unsuspected implications of former/new players. Int J Biol Sci 2020; 16:3018-3027. [PMID: 33061813 PMCID: PMC7545696 DOI: 10.7150/ijbs.49302] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 09/10/2020] [Indexed: 12/13/2022] Open
Abstract
S-adenosylmethionine supplies methyl groups to many acceptors, including lipids, proteins, RNA, DNA, and a wide range of small molecules. It acts as the precursor in the biosynthesis of metal ion chelating compounds, such as nicotianamine and phytosiderophores, of the polyamines spermidine and spermine and of some plant hormones. Finally, it is the source of catalytic 5′-deoxyadenosyl radicals. Radical S-adenosylmethionine (SAM) enzymes (RS) represent one of the most abundant groups (more than 100,000) of enzymes, exerting a plethora of biological functions, some of which are still unknown. In this work, we will focus on two RS: CDK5RAP1 and CDKAL1, both of which are involved in tRNA modifications that result in important tRNA folding and stability and in maintaining high translational fidelity. Based on this crucial role, their impairment can be important in the development of different human diseases.
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Affiliation(s)
- Raffaella Adami
- Department of Health Science University of Milan via A. di Rudinì 8 20142 Milan
| | - Daniele Bottai
- Department of Health Science University of Milan via A. di Rudinì 8 20142 Milan
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