1
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Qian C, Wang L. Unraveling the Structure-Spectrum Relationship of Yeast Phenylalanine Transfer RNA: Insights from Theoretical Modeling of Infrared Spectroscopy. Biochemistry 2024; 63:2075-2088. [PMID: 39099399 DOI: 10.1021/acs.biochem.4c00236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/06/2024]
Abstract
Yeast phenylalanine tRNA (tRNAphe) is a paradigmatic model in structural biology. In this work, we combine molecular dynamics simulations and spectroscopy modeling to establish a direct link between its structure, conformational dynamics, and infrared (IR) spectra. Employing recently developed vibrational frequency maps and coupling models, we apply a mixed quantum/classical treatment of the line shape theory to simulate the IR spectra of tRNAphe in the 1600-1800 cm-1 region across its folded and unfolded conformations and under varying concentrations of Mg2+ ions. The predicted IR spectra of folded and unfolded tRNAphe are in good agreement with experimental measurements, validating our theoretical framework. We then elucidate how the characteristic L-shaped tertiary structure of the tRNA and its modulation in response to diverse chemical environments give rise to distinct IR absorption peaks and line shapes. These calculations effectively bridge IR spectroscopy experiments and atomistic molecular simulations, unraveling the molecular origins of the observed IR spectra of tRNAphe. This work presents a robust theoretical protocol for modeling the IR spectroscopy of nucleic acids, which will facilitate its application as a sensitive probe for detecting the fluctuating secondary and tertiary structures of these essential biological macromolecules.
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Affiliation(s)
- Cheng Qian
- Department of Chemistry and Chemical Biology, Institute for Quantitative Biomedicine, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Lu Wang
- Department of Chemistry and Chemical Biology, Institute for Quantitative Biomedicine, Rutgers University, Piscataway, New Jersey 08854, United States
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2
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Skeparnias I, Bou-Nader C, Anastasakis DG, Fan L, Wang YX, Hafner M, Zhang J. Structural basis of MALAT1 RNA maturation and mascRNA biogenesis. Nat Struct Mol Biol 2024:10.1038/s41594-024-01340-4. [PMID: 38956168 DOI: 10.1038/s41594-024-01340-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Accepted: 05/29/2024] [Indexed: 07/04/2024]
Abstract
The metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) long noncoding RNA (lncRNA) has key roles in regulating transcription, splicing, tumorigenesis, etc. Its maturation and stabilization require precise processing by RNase P, which simultaneously initiates the biogenesis of a 3' cytoplasmic MALAT1-associated small cytoplasmic RNA (mascRNA). mascRNA was proposed to fold into a transfer RNA (tRNA)-like secondary structure but lacks eight conserved linking residues required by the canonical tRNA fold. Here we report crystal structures of human mascRNA before and after processing, which reveal an ultracompact, quasi-tRNA-like structure. Despite lacking all linker residues, mascRNA faithfully recreates the characteristic 'elbow' feature of tRNAs to recruit RNase P and ElaC homolog protein 2 (ELAC2) for processing, which exhibit distinct substrate specificities. Rotation and repositioning of the D-stem and anticodon regions preclude mascRNA from aminoacylation, avoiding interference with translation. Therefore, a class of metazoan lncRNA loci uses a previously unrecognized, unusually streamlined quasi-tRNA architecture to recruit select tRNA-processing enzymes while excluding others to drive bespoke RNA biogenesis, processing and maturation.
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Affiliation(s)
- Ilias Skeparnias
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA
| | - Charles Bou-Nader
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA
| | - Dimitrios G Anastasakis
- RNA Molecular Biology Laboratory, National Institute for Arthritis and Musculoskeletal and Skin Disease, Bethesda, MD, USA
| | - Lixin Fan
- Basic Science Program, Frederick National Laboratory for Cancer Research, Small-Angle X-Ray Scattering Core Facility of National Cancer Institute, Frederick, MD, USA
| | - Yun-Xing Wang
- Basic Science Program, Frederick National Laboratory for Cancer Research, Small-Angle X-Ray Scattering Core Facility of National Cancer Institute, Frederick, MD, USA
- Structural Biophysics Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD, USA
| | - Markus Hafner
- RNA Molecular Biology Laboratory, National Institute for Arthritis and Musculoskeletal and Skin Disease, Bethesda, MD, USA
| | - Jinwei Zhang
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA.
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3
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Weiss JL, Decker JC, Bolano A, Krahn N. Tuning tRNAs for improved translation. Front Genet 2024; 15:1436860. [PMID: 38983271 PMCID: PMC11231383 DOI: 10.3389/fgene.2024.1436860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2024] [Accepted: 06/06/2024] [Indexed: 07/11/2024] Open
Abstract
Transfer RNAs have been extensively explored as the molecules that translate the genetic code into proteins. At this interface of genetics and biochemistry, tRNAs direct the efficiency of every major step of translation by interacting with a multitude of binding partners. However, due to the variability of tRNA sequences and the abundance of diverse post-transcriptional modifications, a guidebook linking tRNA sequences to specific translational outcomes has yet to be elucidated. Here, we review substantial efforts that have collectively uncovered tRNA engineering principles that can be used as a guide for the tuning of translation fidelity. These principles have allowed for the development of basic research, expansion of the genetic code with non-canonical amino acids, and tRNA therapeutics.
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Affiliation(s)
- Joshua L Weiss
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States
| | - J C Decker
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States
| | - Ariadna Bolano
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States
| | - Natalie Krahn
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States
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4
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Kirsebom LA, Liu F, McClain WH. The discovery of a catalytic RNA within RNase P and its legacy. J Biol Chem 2024; 300:107318. [PMID: 38677513 PMCID: PMC11143913 DOI: 10.1016/j.jbc.2024.107318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 04/12/2024] [Accepted: 04/13/2024] [Indexed: 04/29/2024] Open
Abstract
Sidney Altman's discovery of the processing of one RNA by another RNA that acts like an enzyme was revolutionary in biology and the basis for his sharing the 1989 Nobel Prize in Chemistry with Thomas Cech. These breakthrough findings support the key role of RNA in molecular evolution, where replicating RNAs (and similar chemical derivatives) either with or without peptides functioned in protocells during the early stages of life on Earth, an era referred to as the RNA world. Here, we cover the historical background highlighting the work of Altman and his colleagues and the subsequent efforts of other researchers to understand the biological function of RNase P and its catalytic RNA subunit and to employ it as a tool to downregulate gene expression. We primarily discuss bacterial RNase P-related studies but acknowledge that many groups have significantly contributed to our understanding of archaeal and eukaryotic RNase P, as reviewed in this special issue and elsewhere.
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Affiliation(s)
- Leif A Kirsebom
- Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden.
| | - Fenyong Liu
- School of Public Health, University of California, Berkeley, California, USA.
| | - William H McClain
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin, USA.
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5
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Ji J, Yu NJ, Kleiner RE. Sequence- and Structure-Specific tRNA Dihydrouridylation by hDUS2. ACS CENTRAL SCIENCE 2024; 10:803-812. [PMID: 38680565 PMCID: PMC11046453 DOI: 10.1021/acscentsci.3c01382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 02/22/2024] [Accepted: 02/26/2024] [Indexed: 05/01/2024]
Abstract
The post-transcriptional reduction of uridine to dihydrouridine (D) by dihydrouridine synthase (DUS) enzymes is among the most ubiquitous transformations in RNA biology. D is found at multiple sites in tRNAs, and studies in yeast have proposed that each of the four eukaryotic DUS enzymes modifies a different site; however, the molecular basis for this exquisite selectivity is unknown, and human DUS enzymes have remained largely uncharacterized. Here we investigate the substrate specificity of human dihydrouridine synthase 2 (hDUS2) using mechanism-based cross-linking with 5-bromouridine (5-BrUrd)-modified oligonucleotide probes and in vitro dihydrouridylation assays. We find that hDUS2 exclusively modifies U20 across diverse tRNA substrates and identify a minimal GU sequence within the tRNA D loop that underlies selective substrate modification. Further, we use our mechanism-based platform to screen small molecule inhibitors of hDUS2, a potential anticancer target. Our work elucidates the principles of substrate modification by a conserved DUS and provides a general platform for studying RNA modifying enzymes with sequence-defined activity-based probes.
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Affiliation(s)
- Jingwei Ji
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Nathan J. Yu
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Ralph E. Kleiner
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
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6
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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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7
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Zhang J. Recognition of the tRNA structure: Everything everywhere but not all at once. Cell Chem Biol 2024; 31:36-52. [PMID: 38159570 PMCID: PMC10843564 DOI: 10.1016/j.chembiol.2023.12.008] [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: 08/27/2023] [Revised: 12/02/2023] [Accepted: 12/11/2023] [Indexed: 01/03/2024]
Abstract
tRNAs are among the most abundant and essential biomolecules in cells. These spontaneously folding, extensively structured yet conformationally flexible anionic polymers literally bridge the worlds of RNAs and proteins, and serve as Rosetta stones that decipher and interpret the genetic code. Their ubiquitous presence, functional irreplaceability, and privileged access to cellular compartments and ribosomes render them prime targets for both endogenous regulation and exogenous manipulation. There is essentially no part of the tRNA that is not touched by another interaction partner, either as programmed or imposed by an external adversary. Recent progresses in genetic, biochemical, and structural analyses of the tRNA interactome produced a wealth of new knowledge into their interaction networks, regulatory functions, and molecular interfaces. In this review, I describe and illustrate the general principles of tRNA recognition by proteins and other RNAs, and discuss the underlying molecular mechanisms that deliver affinity, specificity, and functional competency.
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Affiliation(s)
- Jinwei Zhang
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD 20892, USA.
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8
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Lei L, Burton ZF. The 3 31 Nucleotide Minihelix tRNA Evolution Theorem and the Origin of Life. Life (Basel) 2023; 13:2224. [PMID: 38004364 PMCID: PMC10672568 DOI: 10.3390/life13112224] [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: 10/16/2023] [Revised: 11/08/2023] [Accepted: 11/16/2023] [Indexed: 11/26/2023] Open
Abstract
There are no theorems (proven theories) in the biological sciences. We propose that the 3 31 nt minihelix tRNA evolution theorem be universally accepted as one. The 3 31 nt minihelix theorem completely describes the evolution of type I and type II tRNAs from ordered precursors (RNA repeats and inverted repeats). Despite the diversification of tRNAome sequences, statistical tests overwhelmingly support the theorem. Furthermore, the theorem relates the dominant pathway for the origin of life on Earth, specifically, how tRNAomes and the genetic code may have coevolved. Alternate models for tRNA evolution (i.e., 2 minihelix, convergent and accretion models) are falsified. In the context of the pre-life world, tRNA was a molecule that, via mutation, could modify anticodon sequences and teach itself to code. Based on the tRNA sequence, we relate the clearest history to date of the chemical evolution of life. From analysis of tRNA evolution, ribozyme-mediated RNA ligation was a primary driving force in the evolution of complexity during the pre-life-to-life transition. TRNA formed the core for the evolution of living systems on Earth.
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Affiliation(s)
- Lei Lei
- School of Biological Sciences, University of New England, Biddeford, ME 04005, USA;
| | - Zachary Frome Burton
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
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9
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Ji J, Yu NJ, Kleiner RE. A minimal sequence motif drives selective tRNA dihydrouridylation by hDUS2. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.04.565616. [PMID: 37961591 PMCID: PMC10635142 DOI: 10.1101/2023.11.04.565616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
The post-transcriptional reduction of uridine to dihydrouridine (D) by dihydrouridine synthase (DUS) enzymes is among the most ubiquitous transformations in RNA biology. D is found at multiple sites in tRNAs and studies in yeast have proposed that each of the four eukaryotic DUS enzymes modifies a different site, however the molecular basis for this exquisite selectivity is unknown and human DUS enzymes have remained largely uncharacterized. Here we investigate the substrate specificity of human dihydrouridine synthase 2 (hDUS2) using mechanism-based crosslinking with 5-bromouridine (5-BrUrd)-modified oligonucleotide probes and in vitro dihydrouridylation assays. We find that hDUS2 modifies U20 in the D loop of diverse tRNA substrates and identify a minimal GU motif within the tRNA tertiary fold required for directing its activity. Further, we use our mechanism-based platform to screen small molecule inhibitors of hDUS2, a potential anti-cancer target. Our work elucidates the principles of substrate modification by a conserved DUS and provides a general platform to studying RNA modifying enzymes with sequence-defined activity-based probes.
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10
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Suddala KC, Yoo J, Fan L, Zuo X, Wang YX, Chung HS, Zhang J. Direct observation of tRNA-chaperoned folding of a dynamic mRNA ensemble. Nat Commun 2023; 14:5438. [PMID: 37673863 PMCID: PMC10482949 DOI: 10.1038/s41467-023-41155-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 08/24/2023] [Indexed: 09/08/2023] Open
Abstract
T-box riboswitches are multi-domain noncoding RNAs that surveil individual amino acid availabilities in most Gram-positive bacteria. T-boxes directly bind specific tRNAs, query their aminoacylation status to detect starvation, and feedback control the transcription or translation of downstream amino-acid metabolic genes. Most T-boxes rapidly recruit their cognate tRNA ligands through an intricate three-way stem I-stem II-tRNA interaction, whose establishment is not understood. Using single-molecule FRET, SAXS, and time-resolved fluorescence, we find that the free T-box RNA assumes a broad distribution of open, semi-open, and closed conformations that only slowly interconvert. tRNA directly binds all three conformers with distinct kinetics, triggers nearly instantaneous collapses of the open conformations, and returns the T-box RNA to their pre-binding conformations upon dissociation. This scissors-like dynamic behavior is enabled by a hinge-like pseudoknot domain which poises the T-box for rapid tRNA-induced domain closure. This study reveals tRNA-chaperoned folding of flexible, multi-domain mRNAs through a Venus flytrap-like mechanism.
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Affiliation(s)
- Krishna C Suddala
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, 20892, USA
| | - Janghyun Yoo
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, 20892, USA
| | - Lixin Fan
- Basic Science Program, Frederick National Laboratory for Cancer Research, Small-Angle X-Ray Scattering Core Facility of National Cancer Institute, Frederick, MD, 21702, USA
| | - Xiaobing Zuo
- X-ray Science Division, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Yun-Xing Wang
- Basic Science Program, Frederick National Laboratory for Cancer Research, Small-Angle X-Ray Scattering Core Facility of National Cancer Institute, Frederick, MD, 21702, USA
- Structural Biophysics Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD, 21702, USA
| | - Hoi Sung Chung
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, 20892, USA.
| | - Jinwei Zhang
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, 20892, USA.
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11
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Antika TR, Nazilah KR, Chrestella DJ, Wang TL, Tseng YK, Wang SC, Hsu HL, Wang SW, Chuang TH, Pan HC, Horng JC, Wang CC. Sequence-specific targeting of Caenorhabditis elegans C-Ala to the D-loop of tRNA Ala. J Biol Chem 2023; 299:105149. [PMID: 37567477 PMCID: PMC10485164 DOI: 10.1016/j.jbc.2023.105149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 08/01/2023] [Accepted: 08/04/2023] [Indexed: 08/13/2023] Open
Abstract
Alanyl-tRNA synthetase retains a conserved prototype structure throughout its biology. Nevertheless, its C-terminal domain (C-Ala) is highly diverged and has been shown to play a role in either tRNA or DNA binding. Interestingly, we discovered that Caenorhabditis elegans cytoplasmic C-Ala (Ce-C-Alac) robustly binds both ligands. How Ce-C-Alac targets its cognate tRNA and whether a similar feature is conserved in its mitochondrial counterpart remain elusive. We show that the N- and C-terminal subdomains of Ce-C-Alac are responsible for DNA and tRNA binding, respectively. Ce-C-Alac specifically recognized the conserved invariant base G18 in the D-loop of tRNAAla through a highly conserved lysine residue, K934. Despite bearing little resemblance to other C-Ala domains, C. elegans mitochondrial C-Ala robustly bound both tRNAAla and DNA and maintained targeting specificity for the D-loop of its cognate tRNA. This study uncovers the underlying mechanism of how C. elegans C-Ala specifically targets the D-loop of tRNAAla.
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Affiliation(s)
- Titi Rindi Antika
- Department of Life Sciences, National Central University, Taoyuan, Taiwan
| | | | | | - Tzu-Ling Wang
- Graduate Institute of Mathematics and Science Education, National Tsing Hua University, Hsinchu City, Taiwan
| | - Yi-Kuan Tseng
- Graduate Institute of Statistics, National Central University, Taoyuan, Taiwan
| | - Sun-Chong Wang
- Department of Biomedical Sciences and Engineering, National Central University, Taoyuan, Taiwan
| | - Hsin-Ling Hsu
- Institute of Molecular and Genomic Medicine, National Health Research Institutes, Miaoli, Taiwan
| | - Shao-Win Wang
- Institute of Molecular and Genomic Medicine, National Health Research Institutes, Miaoli, Taiwan
| | - Tsung-Hsien Chuang
- Immunology Research Center, National Health Research Institutes, Miaoli, Taiwan
| | - Hung-Chuan Pan
- Department of Neurosurgery, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Jia-Cherng Horng
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan
| | - Chien-Chia Wang
- Department of Life Sciences, National Central University, Taoyuan, Taiwan.
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12
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Kuhle B, Hirschi M, Doerfel LK, Lander GC, Schimmel P. Structural basis for a degenerate tRNA identity code and the evolution of bimodal specificity in human mitochondrial tRNA recognition. Nat Commun 2023; 14:4794. [PMID: 37558671 PMCID: PMC10412605 DOI: 10.1038/s41467-023-40354-2] [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: 12/14/2022] [Accepted: 07/22/2023] [Indexed: 08/11/2023] Open
Abstract
Animal mitochondrial gene expression relies on specific interactions between nuclear-encoded aminoacyl-tRNA synthetases and mitochondria-encoded tRNAs. Their evolution involves an antagonistic interplay between strong mutation pressure on mtRNAs and selection pressure to maintain their essential function. To understand the molecular consequences of this interplay, we analyze the human mitochondrial serylation system, in which one synthetase charges two highly divergent mtRNASer isoacceptors. We present the cryo-EM structure of human mSerRS in complex with mtRNASer(UGA), and perform a structural and functional comparison with the mSerRS-mtRNASer(GCU) complex. We find that despite their common function, mtRNASer(UGA) and mtRNASer(GCU) show no constrain to converge on shared structural or sequence identity motifs for recognition by mSerRS. Instead, mSerRS evolved a bimodal readout mechanism, whereby a single protein surface recognizes degenerate identity features specific to each mtRNASer. Our results show how the mutational erosion of mtRNAs drove a remarkable innovation of intermolecular specificity rules, with multiple evolutionary pathways leading to functionally equivalent outcomes.
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Affiliation(s)
- Bernhard Kuhle
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, 92037, USA.
- Department of Cellular Biochemistry, University Medical Center Göttingen, 37073, Göttingen, Germany.
| | - Marscha Hirschi
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, 92121, USA
| | - Lili K Doerfel
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, 92121, USA
| | - Gabriel C Lander
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, 92121, USA
| | - Paul Schimmel
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, 92037, USA
- The Scripps Florida Research Institute at the University of Florida, Jupiter, FL, 33458, USA
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13
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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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14
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Holm M, Natchiar SK, Rundlet EJ, Myasnikov AG, Watson ZL, Altman RB, Wang HY, Taunton J, Blanchard SC. mRNA decoding in human is kinetically and structurally distinct from bacteria. Nature 2023; 617:200-207. [PMID: 37020024 PMCID: PMC10156603 DOI: 10.1038/s41586-023-05908-w] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Accepted: 03/01/2023] [Indexed: 04/07/2023]
Abstract
In all species, ribosomes synthesize proteins by faithfully decoding messenger RNA (mRNA) nucleotide sequences using aminoacyl-tRNA substrates. Current knowledge of the decoding mechanism derives principally from studies on bacterial systems1. Although key features are conserved across evolution2, eukaryotes achieve higher-fidelity mRNA decoding than bacteria3. In human, changes in decoding fidelity are linked to ageing and disease and represent a potential point of therapeutic intervention in both viral and cancer treatment4-6. Here we combine single-molecule imaging and cryogenic electron microscopy methods to examine the molecular basis of human ribosome fidelity to reveal that the decoding mechanism is both kinetically and structurally distinct from that of bacteria. Although decoding is globally analogous in both species, the reaction coordinate of aminoacyl-tRNA movement is altered on the human ribosome and the process is an order of magnitude slower. These distinctions arise from eukaryote-specific structural elements in the human ribosome and in the elongation factor eukaryotic elongation factor 1A (eEF1A) that together coordinate faithful tRNA incorporation at each mRNA codon. The distinct nature and timing of conformational changes within the ribosome and eEF1A rationalize how increased decoding fidelity is achieved and potentially regulated in eukaryotic species.
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Affiliation(s)
- Mikael Holm
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, TN, USA
| | - S Kundhavai Natchiar
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, TN, USA
| | - Emily J Rundlet
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, TN, USA
- Tri-Institutional PhD Program in Chemical Biology, Weill Cornell Medicine, New York, NY, USA
| | - Alexander G Myasnikov
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, TN, USA
- Dubochet Center for Imaging (DCI), EPFL, Lausanne, Switzerland
| | - Zoe L Watson
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, TN, USA
- California Institute for Quantitative Biosciences, University of California, Berkeley, CA, USA
| | - Roger B Altman
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, TN, USA
| | - Hao-Yuan Wang
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA, USA
| | - Jack Taunton
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA, USA
| | - Scott C Blanchard
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, TN, USA.
- Chemical Biology & Therapeutics, St Jude Children's Research Hospital, Memphis, TN, USA.
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15
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Antika TR, Chrestella DJ, Tseng YK, Yeh YH, Hsiao CD, Wang CC. A naturally occurring mini-alanyl-tRNA synthetase. Commun Biol 2023; 6:314. [PMID: 36959394 PMCID: PMC10036535 DOI: 10.1038/s42003-023-04699-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 03/13/2023] [Indexed: 03/25/2023] Open
Abstract
Alanyl-tRNA synthetase (AlaRS) retains a conserved prototype structure throughout its biology, consisting of catalytic, tRNA-recognition, editing, and C-Ala domains. The catalytic and tRNA-recognition domains catalyze aminoacylation, the editing domain hydrolyzes mischarged tRNAAla, and C-Ala-the major tRNA-binding module-targets the elbow of the L-shaped tRNAAla. Interestingly, a mini-AlaRS lacking the editing and C-Ala domains is recovered from the Tupanvirus of the amoeba Acanthamoeba castellanii. Here we show that Tupanvirus AlaRS (TuAlaRS) is phylogenetically related to its host's AlaRS. Despite lacking the conserved amino acid residues responsible for recognition of the identity element of tRNAAla (G3:U70), TuAlaRS still specifically recognized G3:U70-containing tRNAAla. In addition, despite lacking C-Ala, TuAlaRS robustly binds and charges microAla (an RNA substrate corresponding to the acceptor stem of tRNAAla) as well as tRNAAla, indicating that TuAlaRS exclusively targets the acceptor stem. Moreover, this mini-AlaRS could functionally substitute for yeast AlaRS in vivo. This study suggests that TuAlaRS has developed a new tRNA-binding mode to compensate for the loss of C-Ala.
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Affiliation(s)
- Titi Rindi Antika
- Department of Life Sciences, National Central University, Zhongli District, Taoyuan, 320317, Taiwan
| | - Dea Jolie Chrestella
- Department of Life Sciences, National Central University, Zhongli District, Taoyuan, 320317, Taiwan
| | - Yi-Kuan Tseng
- Graduate Institute of Statistics, National Central University, Zhongli District, Taoyuan, 320317, Taiwan
| | - Yi-Hung Yeh
- Institute of Molecular Biology, Academia Sinica, Nankang District, Taipei, 11529, Taiwan
| | - Chwan-Deng Hsiao
- Institute of Molecular Biology, Academia Sinica, Nankang District, Taipei, 11529, Taiwan
| | - Chien-Chia Wang
- Department of Life Sciences, National Central University, Zhongli District, Taoyuan, 320317, Taiwan.
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16
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Giarimoglou N, Kouvela A, Maniatis A, Papakyriakou A, Zhang J, Stamatopoulou V, Stathopoulos C. A Riboswitch-Driven Era of New Antibacterials. Antibiotics (Basel) 2022; 11:antibiotics11091243. [PMID: 36140022 PMCID: PMC9495366 DOI: 10.3390/antibiotics11091243] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 09/01/2022] [Accepted: 09/08/2022] [Indexed: 11/26/2022] Open
Abstract
Riboswitches are structured non-coding RNAs found in the 5′ UTR of important genes for bacterial metabolism, virulence and survival. Upon the binding of specific ligands that can vary from simple ions to complex molecules such as nucleotides and tRNAs, riboswitches change their local and global mRNA conformations to affect downstream transcription or translation. Due to their dynamic nature and central regulatory role in bacterial metabolism, riboswitches have been exploited as novel RNA-based targets for the development of new generation antibacterials that can overcome drug-resistance problems. During recent years, several important riboswitch structures from many bacterial representatives, including several prominent human pathogens, have shown that riboswitches are ideal RNA targets for new compounds that can interfere with their structure and function, exhibiting much reduced resistance over time. Most interestingly, mainstream antibiotics that target the ribosome have been shown to effectively modulate the regulatory behavior and capacity of several riboswitches, both in vivo and in vitro, emphasizing the need for more in-depth studies and biological evaluation of new antibiotics. Herein, we summarize the currently known compounds that target several main riboswitches and discuss the role of mainstream antibiotics as modulators of T-box riboswitches, in the dawn of an era of novel inhibitors that target important bacterial regulatory RNAs.
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Affiliation(s)
- Nikoleta Giarimoglou
- Department of Biochemistry, School of Medicine, University of Patras, 26504 Patras, Greece
| | - Adamantia Kouvela
- Department of Biochemistry, School of Medicine, University of Patras, 26504 Patras, Greece
| | - Alexandros Maniatis
- Department of Biochemistry, School of Medicine, University of Patras, 26504 Patras, Greece
| | - Athanasios Papakyriakou
- Institute of Biosciences & Applications, National Centre for Scientific Research “Demokritos”, Ag. Paraskevi, 15341 Athens, Greece
| | - Jinwei Zhang
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD 20892, USA
| | | | - Constantinos Stathopoulos
- Department of Biochemistry, School of Medicine, University of Patras, 26504 Patras, Greece
- Correspondence: ; Tel.: +30-2610-997932
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17
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Kuhle B, Hirschi M, Doerfel LK, Lander GC, Schimmel P. Structural basis for shape-selective recognition and aminoacylation of a D-armless human mitochondrial tRNA. Nat Commun 2022; 13:5100. [PMID: 36042193 PMCID: PMC9427863 DOI: 10.1038/s41467-022-32544-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 08/04/2022] [Indexed: 02/05/2023] Open
Abstract
Human mitochondrial gene expression relies on the specific recognition and aminoacylation of mitochondrial tRNAs (mtRNAs) by nuclear-encoded mitochondrial aminoacyl-tRNA synthetases (mt-aaRSs). Despite their essential role in cellular energy homeostasis, strong mutation pressure and genetic drift have led to an unparalleled sequence erosion of animal mtRNAs. The structural and functional consequences of this erosion are not understood. Here, we present cryo-EM structures of the human mitochondrial seryl-tRNA synthetase (mSerRS) in complex with mtRNASer(GCU). These structures reveal a unique mechanism of substrate recognition and aminoacylation. The mtRNASer(GCU) is highly degenerated, having lost the entire D-arm, tertiary core, and stable L-shaped fold that define canonical tRNAs. Instead, mtRNASer(GCU) evolved unique structural innovations, including a radically altered T-arm topology that serves as critical identity determinant in an unusual shape-selective readout mechanism by mSerRS. Our results provide a molecular framework to understand the principles of mito-nuclear co-evolution and specialized mechanisms of tRNA recognition in mammalian mitochondrial gene expression.
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Affiliation(s)
- Bernhard Kuhle
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, 92037, USA.
| | - Marscha Hirschi
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, 92121, USA
| | - Lili K Doerfel
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, 92121, USA
| | - Gabriel C Lander
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, 92121, USA
| | - Paul Schimmel
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, 92037, USA
- The Scripps Florida Research Institute at the University of Florida, Jupiter, FL, 33458, USA
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18
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Xu B, Zhu Y, Cao C, Chen H, Jin Q, Li G, Ma J, Yang SL, Zhao J, Zhu J, Ding Y, Fang X, Jin Y, Kwok CK, Ren A, Wan Y, Wang Z, Xue Y, Zhang H, Zhang QC, Zhou Y. Recent advances in RNA structurome. SCIENCE CHINA. LIFE SCIENCES 2022; 65:1285-1324. [PMID: 35717434 PMCID: PMC9206424 DOI: 10.1007/s11427-021-2116-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Accepted: 04/01/2022] [Indexed: 12/27/2022]
Abstract
RNA structures are essential to support RNA functions and regulation in various biological processes. Recently, a range of novel technologies have been developed to decode genome-wide RNA structures and novel modes of functionality across a wide range of species. In this review, we summarize key strategies for probing the RNA structurome and discuss the pros and cons of representative technologies. In particular, these new technologies have been applied to dissect the structural landscape of the SARS-CoV-2 RNA genome. We also summarize the functionalities of RNA structures discovered in different regulatory layers-including RNA processing, transport, localization, and mRNA translation-across viruses, bacteria, animals, and plants. We review many versatile RNA structural elements in the context of different physiological and pathological processes (e.g., cell differentiation, stress response, and viral replication). Finally, we discuss future prospects for RNA structural studies to map the RNA structurome at higher resolution and at the single-molecule and single-cell level, and to decipher novel modes of RNA structures and functions for innovative applications.
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Affiliation(s)
- Bingbing Xu
- MOE Laboratory of Biosystems Homeostasis & Protection, Innovation Center for Cell Signaling Network, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Yanda Zhu
- MOE Laboratory of Biosystems Homeostasis & Protection, Innovation Center for Cell Signaling Network, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Changchang Cao
- Key Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Hao Chen
- Life Sciences Institute, Zhejiang University, Hangzhou, 310058, China
| | - Qiongli Jin
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Guangnan Li
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Junfeng Ma
- Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Siwy Ling Yang
- Stem Cell and Regenerative Biology, Genome Institute of Singapore, A*STAR, Singapore, Singapore
| | - Jieyu Zhao
- Department of Chemistry, and State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon Tong, Hong Kong SAR, China
| | - Jianghui Zhu
- MOE Key Laboratory of Bioinformatics, Beijing Advanced Innovation Center for Structural Biology and Frontier Research Center for Biological Structure, Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084, China
| | - Yiliang Ding
- Department of Cell and Developmental Biology, John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, United Kingdom.
| | - Xianyang Fang
- Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China.
| | - Yongfeng Jin
- MOE Laboratory of Biosystems Homeostasis & Protection, Innovation Center for Cell Signaling Network, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.
| | - Chun Kit Kwok
- Department of Chemistry, and State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon Tong, Hong Kong SAR, China.
- Shenzhen Research Institute of City University of Hong Kong, Shenzhen, 518057, China.
| | - Aiming Ren
- Life Sciences Institute, Zhejiang University, Hangzhou, 310058, China.
| | - Yue Wan
- Stem Cell and Regenerative Biology, Genome Institute of Singapore, A*STAR, Singapore, Singapore.
| | - Zhiye Wang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.
| | - Yuanchao Xue
- Key Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.
- University of Chinese Academy of Sciences, Beijing, 100101, China.
| | - Huakun Zhang
- Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun, 130024, China.
| | - Qiangfeng Cliff Zhang
- MOE Key Laboratory of Bioinformatics, Beijing Advanced Innovation Center for Structural Biology and Frontier Research Center for Biological Structure, Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China.
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084, China.
| | - Yu Zhou
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, 430072, China.
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19
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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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20
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Giarimoglou N, Kouvela A, Patsi I, Zhang J, Stamatopoulou V, Stathopoulos C. Lineage-specific insertions in T-box riboswitches modulate antibiotic binding and action. Nucleic Acids Res 2022; 50:5834-5849. [PMID: 35580054 PMCID: PMC9177973 DOI: 10.1093/nar/gkac359] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 04/21/2022] [Accepted: 05/11/2022] [Indexed: 01/27/2023] Open
Abstract
T-box riboswitches (T-boxes) are essential RNA regulatory elements with a remarkable structural diversity, especially among bacterial pathogens. In staphylococci, all glyS T-boxes synchronize glycine supply during synthesis of nascent polypeptides and cell wall formation and are characterized by a conserved and unique insertion in their antiterminator/terminator domain, termed stem Sa. Interestingly, in Staphylococcus aureus the stem Sa can accommodate binding of specific antibiotics, which in turn induce robust and diverse effects on T-box-mediated transcription. In the present study, domain swap mutagenesis and probing analysis were performed to decipher the role of stem Sa. Deletion of stem Sa significantly reduces both the S. aureus glyS T-box-mediated transcription readthrough levels and the ability to discriminate among tRNAGly isoacceptors, both in vitro and in vivo. Moreover, the deletion inverted the previously reported stimulatory effects of specific antibiotics. Interestingly, stem Sa insertion in the terminator/antiterminator domain of Geobacillus kaustophilus glyS T-box, which lacks this domain, resulted in elevated transcription in the presence of tigecycline and facilitated discrimination among proteinogenic and nonproteinogenic tRNAGly isoacceptors. Overall, stem Sa represents a lineage-specific structural feature required for efficient staphylococcal glyS T-box-mediated transcription and it could serve as a species-selective druggable target through its ability to modulate antibiotic binding.
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Affiliation(s)
- Nikoleta Giarimoglou
- Department of Biochemistry, School of Medicine, University of Patras, 26504 Patras, Greece
| | - Adamantia Kouvela
- Department of Biochemistry, School of Medicine, University of Patras, 26504 Patras, Greece
| | - Ioanna Patsi
- Department of Biochemistry, School of Medicine, University of Patras, 26504 Patras, Greece
| | - Jinwei Zhang
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD 20892, USA
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21
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Beernink BM, Lappe RR, Bredow M, Whitham SA. Impacts of RNA Mobility Signals on Virus Induced Somatic and Germline Gene Editing. Front Genome Ed 2022; 4:925088. [PMID: 35755451 PMCID: PMC9219249 DOI: 10.3389/fgeed.2022.925088] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 05/16/2022] [Indexed: 11/13/2022] Open
Abstract
Viral vectors are being engineered to deliver CRISPR/Cas9 components systemically in plants to induce somatic or heritable site-specific mutations. It is hypothesized that RNA mobility signals facilitate entry of viruses or single guide RNAs (sgRNAs) into the shoot apical meristem where germline mutations can occur. Our objective was to understand the impact of RNA mobility signals on virus-induced somatic and germline gene editing in Nicotiana benthamiana and Zea mays. Previously, we showed that foxtail mosaic virus (FoMV) expressing sgRNA induced somatic mutations in N. benthamiana and Z. mays expressing Cas9. Here, we fused RNA mobility signals to sgRNAs targeting the genes encoding either N. benthamiana phytoene desaturase (PDS) or Z. mays high affinity potassium transporter 1 (HKT1). Addition of Arabidopsis thaliana Flowering Locus T (AtFT) and A. thaliana tRNA-Isoleucine (AttRNAIle) did not improve FoMV-induced somatic editing, and neither were sufficient to facilitate germline mutations in N. benthamiana. Maize FT homologs, Centroradialus 16 (ZCN16) and ZCN19, as well as AttRNAIle were found to aid somatic editing in maize but did not enable sgRNAs delivered by FoMV to induce germline mutations. Additional viral guide RNA delivery systems were assessed for somatic and germline mutations in N. benthamiana with the intention of gaining a better understanding of the specificity of mobile signal-facilitated germline editing. Potato virus X (PVX), barley stripe mosaic virus (BSMV), and tobacco rattle virus (TRV) were included in this comparative study, and all three of these viruses delivering sgRNA were able to induce somatic and germline mutations. Unexpectedly, PVX, a potexvirus closely related to FoMV, expressing sgRNA alone induced biallelic edited progeny, indicating that mobility signals are dispensable in virus-induced germline editing. These results show that PVX, BSMV, and TRV expressing sgRNA all have an innate ability to induce mutations in the germline. Our results indicate that mobility signals alone may not be sufficient to enable virus-based delivery of sgRNAs using the viruses, FoMV, PVX, BSMV, and TRV into cell types that result in germline mutations.
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Affiliation(s)
| | | | | | - Steven A. Whitham
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA, United States
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22
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Kazimierczyk M, Wojnicka M, Biała E, Żydowicz-Machtel P, Imiołczyk B, Ostrowski T, Kurzyńska-Kokorniak A, Wrzesinski J. Characteristics of Transfer RNA-Derived Fragments Expressed during Human Renal Cell Development: The Role of Dicer in tRF Biogenesis. Int J Mol Sci 2022; 23:ijms23073644. [PMID: 35409004 PMCID: PMC8998818 DOI: 10.3390/ijms23073644] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 03/23/2022] [Accepted: 03/24/2022] [Indexed: 02/04/2023] Open
Abstract
tRNA-derived fragments participate in the regulation of many processes, such as gene silencing, splicing and translation in many organisms, ranging from bacteria to humans. We were interested to know how tRF abundance changes during the different stages of renal cell development. The research model used here consisted of the following human renal cells: hESCs, HEK-293T, HK-2 and A-489 kidney tumor cells, which, together, mimic the different stages of kidney development. The characteristics of the most abundant tRFs, tRFGly(CCC), tRFVal(AAC) and tRFArg(CCU), were presented. It was found that these parental tRNAs present in cells are the source of many tRFs, thus increasing the pool of potential regulatory RNAs. Indeed, a bioinformatic analysis showed the possibility that tRFGly(CCC) and tRRFVal(AAC) could regulate the activity of a range of kidney proteins. Moreover, the distribution of tRFs and the efficiency of their expression is similar in adult and embryonic stem cells. During the formation of tRFs, HK-2 cells resemble A-498 cancer cells more than other cells. Additionally, we postulate the involvement of Dicer nuclease in the formation of tRF-5b in all the analyzed tRNAs. To confirm this, 293T NoDice cells, which in the absence of Dicer activity do not generate tRF-5b, were used.
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23
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Lai LB, Lai SM, Szymanski ES, Kapur M, Choi EK, Al-Hashimi HM, Ackerman SL, Gopalan V. Structural basis for impaired 5' processing of a mutant tRNA associated with defects in neuronal homeostasis. Proc Natl Acad Sci U S A 2022; 119:e2119529119. [PMID: 35238631 PMCID: PMC8915964 DOI: 10.1073/pnas.2119529119] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 01/09/2022] [Indexed: 02/06/2023] Open
Abstract
SignificanceUnderstanding and treating neurological disorders are global priorities. Some of these diseases are engendered by mutations that cause defects in the cellular synthesis of transfer RNAs (tRNAs), which function as adapter molecules that translate messenger RNAs into proteins. During tRNA biogenesis, ribonuclease P catalyzes removal of the transcribed sequence upstream of the mature tRNA. Here, we focus on a cytoplasmic tRNAArgUCU that is expressed specifically in neurons and, when harboring a particular point mutation, contributes to neurodegeneration in mice. Our results suggest that this mutation favors stable alternative structures that are not cleaved by mouse ribonuclease P and motivate a paradigm that may help to understand the molecular basis for disease-associated mutations in other tRNAs.
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Affiliation(s)
- Lien B. Lai
- Department of Chemistry & Biochemistry, The Ohio State University, Columbus, OH 43210
- Center for RNA Biology, The Ohio State University, Columbus, OH 43210
| | - Stella M. Lai
- Department of Chemistry & Biochemistry, The Ohio State University, Columbus, OH 43210
- Center for RNA Biology, The Ohio State University, Columbus, OH 43210
| | - Eric S. Szymanski
- Department of Biochemistry, School of Medicine, Duke University, Durham, NC 27710
| | - Mridu Kapur
- Department of Cellular and Molecular Medicine, Section of Neurobiology, University of California San Diego, La Jolla, CA 92093
- Howard Hughes Medical Institute, University of California San Diego, La Jolla, CA 92093
| | - Edric K. Choi
- Department of Chemistry & Biochemistry, The Ohio State University, Columbus, OH 43210
- Center for RNA Biology, The Ohio State University, Columbus, OH 43210
| | - Hashim M. Al-Hashimi
- Department of Biochemistry, School of Medicine, Duke University, Durham, NC 27710
| | - Susan L. Ackerman
- Department of Cellular and Molecular Medicine, Section of Neurobiology, University of California San Diego, La Jolla, CA 92093
- Howard Hughes Medical Institute, University of California San Diego, La Jolla, CA 92093
| | - Venkat Gopalan
- Department of Chemistry & Biochemistry, The Ohio State University, Columbus, OH 43210
- Center for RNA Biology, The Ohio State University, Columbus, OH 43210
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24
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Skeparnias I, Zhang J. Cooperativity and Interdependency between RNA Structure and RNA-RNA Interactions. Noncoding RNA 2021; 7:ncrna7040081. [PMID: 34940761 PMCID: PMC8704770 DOI: 10.3390/ncrna7040081] [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: 11/15/2021] [Revised: 12/09/2021] [Accepted: 12/10/2021] [Indexed: 11/16/2022] Open
Abstract
Complex RNA–RNA interactions are increasingly known to play key roles in numerous biological processes from gene expression control to ribonucleoprotein granule formation. By contrast, the nature of these interactions and characteristics of their interfaces, especially those that involve partially or wholly structured RNAs, remain elusive. Herein, we discuss different modalities of RNA–RNA interactions with an emphasis on those that depend on secondary, tertiary, or quaternary structure. We dissect recently structurally elucidated RNA–RNA complexes including RNA triplexes, riboswitches, ribozymes, and reverse transcription complexes. These analyses highlight a reciprocal relationship that intimately links RNA structure formation with RNA–RNA interactions. The interactions not only shape and sculpt RNA structures but also are enabled and modulated by the structures they create. Understanding this two-way relationship between RNA structure and interactions provides mechanistic insights into the expanding repertoire of noncoding RNA functions, and may inform the design of novel therapeutics that target RNA structures or interactions.
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25
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Thomas NK, Poodari VC, Jain M, Olsen HE, Akeson M, Abu-Shumays RL. Direct Nanopore Sequencing of Individual Full Length tRNA Strands. ACS NANO 2021; 15:16642-16653. [PMID: 34618430 PMCID: PMC10189790 DOI: 10.1021/acsnano.1c06488] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
We describe a method for direct tRNA sequencing using the Oxford Nanopore MinION. The principal technical advance is custom adapters that facilitate end-to-end sequencing of individual transfer RNA (tRNA) molecules at subnanometer precision. A second advance is a nanopore sequencing pipeline optimized for tRNA. We tested this method using purified E. coli tRNAfMet, tRNALys, and tRNAPhe samples. 76-92% of individual aligned tRNA sequence reads were full length. As a proof of concept, we showed that nanopore sequencing detected all 43 expected isoacceptors in total E. coli MRE600 tRNA as well as isodecoders that further define that tRNA population. Alignment-based comparisons between the three purified tRNAs and their synthetic controls revealed systematic nucleotide miscalls that were diagnostic of known modifications. Systematic miscalls were also observed proximal to known modifications in total E. coli tRNA alignments, including a highly conserved pseudouridine in the T loop. This work highlights the potential of nanopore direct tRNA sequencing as well as improvements needed to implement tRNA sequencing for human healthcare applications.
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26
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Thomas NK, Poodari VC, Jain M, Olsen HE, Akeson M, Abu-Shumays RL. Direct Nanopore Sequencing of Individual Full Length tRNA Strands. ACS NANO 2021; 15:16642-16653. [PMID: 34618430 DOI: 10.1101/2021.1104.1126.441285] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We describe a method for direct tRNA sequencing using the Oxford Nanopore MinION. The principal technical advance is custom adapters that facilitate end-to-end sequencing of individual transfer RNA (tRNA) molecules at subnanometer precision. A second advance is a nanopore sequencing pipeline optimized for tRNA. We tested this method using purified E. coli tRNAfMet, tRNALys, and tRNAPhe samples. 76-92% of individual aligned tRNA sequence reads were full length. As a proof of concept, we showed that nanopore sequencing detected all 43 expected isoacceptors in total E. coli MRE600 tRNA as well as isodecoders that further define that tRNA population. Alignment-based comparisons between the three purified tRNAs and their synthetic controls revealed systematic nucleotide miscalls that were diagnostic of known modifications. Systematic miscalls were also observed proximal to known modifications in total E. coli tRNA alignments, including a highly conserved pseudouridine in the T loop. This work highlights the potential of nanopore direct tRNA sequencing as well as improvements needed to implement tRNA sequencing for human healthcare applications.
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Affiliation(s)
- Niki K Thomas
- Biomolecular Engineering Department, Genomics Institute, and Center for Molecular Biology of RNA University of California, Santa Cruz, California 95064, United States
| | - Vinay C Poodari
- Biomolecular Engineering Department, Genomics Institute, and Center for Molecular Biology of RNA University of California, Santa Cruz, California 95064, United States
| | - Miten Jain
- Biomolecular Engineering Department, Genomics Institute, and Center for Molecular Biology of RNA University of California, Santa Cruz, California 95064, United States
| | - Hugh E Olsen
- Biomolecular Engineering Department, Genomics Institute, and Center for Molecular Biology of RNA University of California, Santa Cruz, California 95064, United States
| | - Mark Akeson
- Biomolecular Engineering Department, Genomics Institute, and Center for Molecular Biology of RNA University of California, Santa Cruz, California 95064, United States
| | - Robin L Abu-Shumays
- Biomolecular Engineering Department, Genomics Institute, and Center for Molecular Biology of RNA University of California, Santa Cruz, California 95064, United States
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Antoine L, Bahena-Ceron R, Devi Bunwaree H, Gobry M, Loegler V, Romby P, Marzi S. RNA Modifications in Pathogenic Bacteria: Impact on Host Adaptation and Virulence. Genes (Basel) 2021; 12:1125. [PMID: 34440299 PMCID: PMC8394870 DOI: 10.3390/genes12081125] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 07/16/2021] [Accepted: 07/19/2021] [Indexed: 12/19/2022] Open
Abstract
RNA modifications are involved in numerous biological processes and are present in all RNA classes. These modifications can be constitutive or modulated in response to adaptive processes. RNA modifications play multiple functions since they can impact RNA base-pairings, recognition by proteins, decoding, as well as RNA structure and stability. However, their roles in stress, environmental adaptation and during infections caused by pathogenic bacteria have just started to be appreciated. With the development of modern technologies in mass spectrometry and deep sequencing, recent examples of modifications regulating host-pathogen interactions have been demonstrated. They show how RNA modifications can regulate immune responses, antibiotic resistance, expression of virulence genes, and bacterial persistence. Here, we illustrate some of these findings, and highlight the strategies used to characterize RNA modifications, and their potential for new therapeutic applications.
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Affiliation(s)
| | | | | | | | | | | | - Stefano Marzi
- Université de Strasbourg, CNRS, Architecture et Réactivité de l’ARN, UPR 9002, F-67000 Strasbourg, France; (L.A.); (R.B.-C.); (H.D.B.); (M.G.); (V.L.); (P.R.)
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28
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Berg MD, Brandl CJ. Transfer RNAs: diversity in form and function. RNA Biol 2021; 18:316-339. [PMID: 32900285 PMCID: PMC7954030 DOI: 10.1080/15476286.2020.1809197] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 07/31/2020] [Accepted: 08/08/2020] [Indexed: 12/11/2022] Open
Abstract
As the adaptor that decodes mRNA sequence into protein, the basic aspects of tRNA structure and function are central to all studies of biology. Yet the complexities of their properties and cellular roles go beyond the view of tRNAs as static participants in protein synthesis. Detailed analyses through more than 60 years of study have revealed tRNAs to be a fascinatingly diverse group of molecules in form and function, impacting cell biology, physiology, disease and synthetic biology. This review analyzes tRNA structure, biosynthesis and function, and includes topics that demonstrate their diversity and growing importance.
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Affiliation(s)
- Matthew D. Berg
- Department of Biochemistry, The University of Western Ontario, London, Canada
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29
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Sun C, Limbach PA, Addepalli B. Characterization of UVA-Induced Alterations to Transfer RNA Sequences. Biomolecules 2020; 10:E1527. [PMID: 33171700 PMCID: PMC7695249 DOI: 10.3390/biom10111527] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 11/02/2020] [Accepted: 11/05/2020] [Indexed: 02/07/2023] Open
Abstract
Ultraviolet radiation (UVR) adversely affects the integrity of DNA, RNA, and their nucleoside modifications. By employing liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based RNA modification mapping approaches, we identified the transfer RNA (tRNA) regions most vulnerable to photooxidation. Photooxidative damage to the anticodon and variable loop regions was consistently observed in both modified and unmodified sequences of tRNA upon UVA (λ 370 nm) exposure. The extent of oxidative damage measured in terms of oxidized guanosine, however, was higher in unmodified RNA compared to its modified version, suggesting an auxiliary role for nucleoside modifications. The type of oxidation product formed in the anticodon stem-loop region varied with the modification type, status, and whether the tRNA was inside or outside the cell during exposure. Oligonucleotide-based characterization of tRNA following UVA exposure also revealed the presence of novel photoproducts and stable intermediates not observed by nucleoside analysis alone. This approach provides sequence-specific information revealing potential hotspots for UVA-induced damage in tRNAs.
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Affiliation(s)
| | | | - Balasubrahmanyam Addepalli
- Rieveschl Laboratories for Mass Spectrometry, Department of Chemistry, University of Cincinnati, Cincinnati, OH 45221-0172, USA; (C.S.); (P.A.L.)
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30
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Donsbach P, Yee BA, Sanchez-Hevia D, Berenguer J, Aigner S, Yeo GW, Klostermeier D. The Thermus thermophilus DEAD-box protein Hera is a general RNA binding protein and plays a key role in tRNA metabolism. RNA (NEW YORK, N.Y.) 2020; 26:1557-1574. [PMID: 32669294 PMCID: PMC7566566 DOI: 10.1261/rna.075580.120] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 07/05/2020] [Indexed: 06/11/2023]
Abstract
RNA helicases catalyze the ATP-dependent destabilization of RNA duplexes. DEAD-box helicases share a helicase core that mediates ATP binding and hydrolysis, RNA binding and unwinding. Most members of this family contain domains flanking the core that can confer RNA substrate specificity and guide the helicase to a specific RNA. However, the in vivo RNA substrates of most helicases are currently not defined. The DEAD-box helicase Hera from Thermus thermophilus contains a helicase core, followed by a dimerization domain and an RNA binding domain that folds into an RNA recognition motif (RRM). The RRM mediates high affinity binding to an RNA hairpin, and an adjacent duplex is then unwound by the helicase core. Hera is a cold-shock protein, and has been suggested to act as an RNA chaperone under cold-shock conditions. Using crosslinking immunoprecipitation of Hera/RNA complexes and sequencing, we show that Hera binds to a large fraction of T. thermophilus RNAs under normal-growth and cold-shock conditions without a strong sequence preference, in agreement with a structure-specific recognition of RNAs and a general function in RNA metabolism. Under cold-shock conditions, Hera is recruited to RNAs with high propensities to form stable secondary structures. We show that selected RNAs identified, including a set of tRNAs, bind to Hera in vitro, and activate the Hera helicase core. Gene ontology analysis reveals an enrichment of genes related to translation, including mRNAs of ribosomal proteins, tRNAs, tRNA ligases, and tRNA-modifying enzymes, consistent with a key role of Hera in ribosome and tRNA metabolism.
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Affiliation(s)
- Pascal Donsbach
- University of Muenster, Institute for Physical Chemistry, 48149 Muenster, Germany
| | - Brian A Yee
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California 92093, USA
- Stem Cell Program, University of California San Diego, La Jolla, California 92093, USA
- Institute for Genomic Medicine, University of California San Diego, La Jolla, California 92093, USA
| | - Dione Sanchez-Hevia
- Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain
| | - José Berenguer
- Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain
| | - Stefan Aigner
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California 92093, USA
- Stem Cell Program, University of California San Diego, La Jolla, California 92093, USA
- Institute for Genomic Medicine, University of California San Diego, La Jolla, California 92093, USA
| | - Gene W Yeo
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California 92093, USA
- Stem Cell Program, University of California San Diego, La Jolla, California 92093, USA
- Institute for Genomic Medicine, University of California San Diego, La Jolla, California 92093, USA
| | - Dagmar Klostermeier
- University of Muenster, Institute for Physical Chemistry, 48149 Muenster, Germany
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31
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Baulin E, Metelev V, Bogdanov A. Base-intercalated and base-wedged stacking elements in 3D-structure of RNA and RNA-protein complexes. Nucleic Acids Res 2020; 48:8675-8685. [PMID: 32687167 PMCID: PMC7470943 DOI: 10.1093/nar/gkaa610] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 07/05/2020] [Accepted: 07/15/2020] [Indexed: 12/25/2022] Open
Abstract
Along with nucleobase pairing, base-base stacking interactions are one of the two main types of strong non-covalent interactions that define the unique secondary and tertiary structure of RNA. In this paper we studied two subfamilies of nucleobase-inserted stacking structures: (i) with any base intercalated between neighboring nucleotide residues (base-intercalated element, BIE, i + 1); (ii) with any base wedged into a hydrophobic cavity formed by heterocyclic bases of two nucleotides which are one nucleotide apart in sequence (base-wedged element, BWE, i + 2). We have exploited the growing database of natively folded RNA structures in Protein Data Bank to analyze the distribution and structural role of these motifs in RNA. We found that these structural elements initially found in yeast tRNAPhe are quite widespread among the tertiary structures of various RNAs. These motifs perform diverse roles in RNA 3D structure formation and its maintenance. They contribute to the folding of RNA bulges and loops and participate in long-range interactions of single-stranded stretches within RNA macromolecules. Furthermore, both base-intercalated and base-wedged motifs participate directly or indirectly in the formation of RNA functional centers, which interact with various ligands, antibiotics and proteins.
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Affiliation(s)
- Eugene Baulin
- Laboratory of Applied Mathematics, Institute of Mathematical Problems of Biology RAS - the Branch of Keldysh Institute of Applied Mathematics of Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia
| | - Valeriy Metelev
- Department of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Alexey Bogdanov
- To whom correspondence should be addressed. Tel: +7 495 9393143; Fax: +7 495 9393181;
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32
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Rose S, Auxilien S, Havelund JF, Kirpekar F, Huber H, Grosjean H, Douthwaite S. The hyperthermophilic partners Nanoarchaeum and Ignicoccus stabilize their tRNA T-loops via different but structurally equivalent modifications. Nucleic Acids Res 2020; 48:6906-6918. [PMID: 32459340 PMCID: PMC7337903 DOI: 10.1093/nar/gkaa411] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Revised: 04/19/2020] [Accepted: 05/06/2020] [Indexed: 01/31/2023] Open
Abstract
The universal L-shaped tertiary structure of tRNAs is maintained with the help of nucleotide modifications within the D- and T-loops, and these modifications are most extensive within hyperthermophilic species. The obligate-commensal Nanoarchaeum equitans and its phylogenetically-distinct host Ignicoccus hospitalis grow physically coupled under identical hyperthermic conditions. We report here two fundamentally different routes by which these archaea modify the key conserved nucleotide U54 within their tRNA T-loops. In N. equitans, this nucleotide is methylated by the S-adenosylmethionine-dependent enzyme NEQ053 to form m5U54, and a recombinant version of this enzyme maintains specificity for U54 in Escherichia coli. In N. equitans, m5U54 is subsequently thiolated to form m5s2U54. In contrast, I. hospitalis isomerizes U54 to pseudouridine prior to methylating its N1-position and thiolating the O4-position of the nucleobase to form the previously uncharacterized nucleotide m1s4Ψ. The methyl and thiol groups in m1s4Ψ and m5s2U are presented within the T-loop in a spatially identical manner that stabilizes the 3′-endo-anti conformation of nucleotide-54, facilitating stacking onto adjacent nucleotides and reverse-Hoogsteen pairing with nucleotide m1A58. Thus, two distinct structurally-equivalent solutions have evolved independently and convergently to maintain the tertiary fold of tRNAs under extreme hyperthermic conditions.
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Affiliation(s)
- Simon Rose
- Department of Biochemistry & Molecular Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Sylvie Auxilien
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Jesper F Havelund
- Department of Biochemistry & Molecular Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Finn Kirpekar
- Department of Biochemistry & Molecular Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Harald Huber
- Lehrstuhl für Mikrobiologie und Archaeenzentrum, Universität Regensburg, Universitätsstraße 31, D-93053 Regensburg, Germany
| | - Henri Grosjean
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Stephen Douthwaite
- Department of Biochemistry & Molecular Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
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Abstract
Ro60 ribonucleoproteins (RNPs), composed of the ring-shaped Ro 60-kDa (Ro60) protein and noncoding RNAs called Y RNAs, are present in all three domains of life. Ro60 was first described as an autoantigen in patients with rheumatic disease, and Ro60 orthologs have been identified in 3% to 5% of bacterial genomes, spanning the majority of phyla. Their functions have been characterized primarily in Deinococcus radiodurans, the first sequenced bacterium with a recognizable ortholog. In D. radiodurans, the Ro60 ortholog enhances the ability of 3'-to-5' exoribonucleases to degrade structured RNA during several forms of environmental stress. Y RNAs are regulators that inhibit or allow the interactions of Ro60 with other proteins and RNAs. Studies of Ro60 RNPs in other bacteria hint at additional functions, since the most conserved Y RNA contains a domain that is a close tRNA mimic and Ro60 RNPs are often encoded adjacent to components of RNA repair systems.
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Affiliation(s)
- Soyeong Sim
- RNA Biology Laboratory, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, Maryland 21702, USA; , , ,
| | - Kevin Hughes
- RNA Biology Laboratory, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, Maryland 21702, USA; , , ,
- Department of Cell Biology, Yale School of Medicine, New Haven, Connecticut 06510, USA
| | - Xinguo Chen
- RNA Biology Laboratory, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, Maryland 21702, USA; , , ,
| | - Sandra L Wolin
- RNA Biology Laboratory, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, Maryland 21702, USA; , , ,
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34
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Zhang J. Unboxing the T-box riboswitches-A glimpse into multivalent and multimodal RNA-RNA interactions. WILEY INTERDISCIPLINARY REVIEWS-RNA 2020; 11:e1600. [PMID: 32633085 PMCID: PMC7583486 DOI: 10.1002/wrna.1600] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 04/25/2020] [Accepted: 04/29/2020] [Indexed: 12/17/2022]
Abstract
The T-box riboswitches are widespread bacterial noncoding RNAs that directly bind specific tRNAs, sense aminoacylation on bound tRNAs, and switch conformations to control amino-acid metabolism and to maintain nutritional homeostasis. The core mechanisms of tRNA recognition, amino acid sensing, and conformational switching by the T-boxes have been recently elucidated, providing a wealth of new insights into multivalent and multimodal RNA-RNA interactions. This review dissects the structures and tRNA-recognition mechanisms by the Stem I, Stem II, and Discriminator domains, which collectively compose the T-box riboswitches. It further compares and contrasts the two classes of T-boxes that regulate transcription and translation, respectively, and integrates recent findings to derive general themes, trends, and insights into complex RNA-RNA interactions. Specifically, the T-box paradigm reveals that noncoding RNAs can interact with each other through multiple coordinated contacts, concatenation of stacked helices, and mutually induced fit. Numerous tertiary contacts, especially those emanating from strings of single-stranded purines, act in concert to reinforce long-range base-pairing and stacking interactions. These coordinated, mixed-mode contacts allow the T-box RNA to sterically sense aminoacylation on the tRNA using a bipartite steric sieve, and to couple this readout to a conformational switch mediated by tRNA-T-box stacking. Together, the insights gleaned from the T-box riboswitches inform investigations into other complex RNA structures and assemblies, development of T-box-targeted antimicrobials, and may inspire design and engineering of novel RNA sensors, regulators, and interfaces. This article is categorized under: RNA Structure and Dynamics > RNA Structure, Dynamics and Chemistry Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAs Regulatory RNAs/RNAi/Riboswitches > Riboswitches.
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Affiliation(s)
- Jinwei Zhang
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland, USA
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35
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Agrawal S, Karcher D, Ruf S, Bock R. The Functions of Chloroplast Glutamyl-tRNA in Translation and Tetrapyrrole Biosynthesis. PLANT PHYSIOLOGY 2020; 183:263-276. [PMID: 32071153 PMCID: PMC7210637 DOI: 10.1104/pp.20.00009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 01/31/2020] [Indexed: 06/02/2023]
Abstract
The chloroplast glutamyl-tRNA (tRNAGlu) is unique in that it has two entirely different functions. In addition to acting in translation, it serves as the substrate of glutamyl-tRNA reductase (GluTR), the enzyme catalyzing the committed step in the tetrapyrrole biosynthetic pathway. How the tRNAGlu pool is distributed between the two pathways and whether tRNAGlu allocation limits tetrapyrrole biosynthesis and/or protein biosynthesis remains poorly understood. We generated a series of transplastomic tobacco (Nicotiana tabacum) plants to alter tRNAGlu expression levels and introduced a point mutation into the plastid trnE gene, which has been reported to uncouple protein biosynthesis from tetrapyrrole biosynthesis in chloroplasts of the protist Euglena gracilis We show that, rather than comparable uncoupling of the two pathways, the trnE mutation is lethal in tobacco because it inhibits tRNA processing, thus preventing translation of Glu codons. Ectopic expression of the mutated trnE gene uncovered an unexpected inhibition of glutamyl-tRNA reductase by immature tRNAGlu We further demonstrate that whereas overexpression of tRNAGlu does not affect tetrapyrrole biosynthesis, reduction of GluTR activity through inhibition by tRNAGlu precursors causes tetrapyrrole synthesis to become limiting in early plant development when active photosystem biogenesis provokes a high demand for de novo chlorophyll biosynthesis. Taken together, our findings provide insight into the roles of tRNAGlu at the intersection of protein biosynthesis and tetrapyrrole biosynthesis.
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Affiliation(s)
- Shreya Agrawal
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
| | - Daniel Karcher
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
| | - Stephanie Ruf
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
| | - Ralph Bock
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
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36
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Structural basis for ribosome recycling by RRF and tRNA. Nat Struct Mol Biol 2019; 27:25-32. [PMID: 31873307 DOI: 10.1038/s41594-019-0350-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 11/12/2019] [Indexed: 11/08/2022]
Abstract
The bacterial ribosome is recycled into subunits by two conserved proteins, elongation factor G (EF-G) and the ribosome recycling factor (RRF). The molecular basis for ribosome recycling by RRF and EF-G remains unclear. Here, we report the crystal structure of a posttermination Thermus thermophilus 70S ribosome complexed with EF-G, RRF and two transfer RNAs at a resolution of 3.5 Å. The deacylated tRNA in the peptidyl (P) site moves into a previously unsuspected state of binding (peptidyl/recycling, p/R) that is analogous to that seen during initiation. The terminal end of the p/R-tRNA forms nonfavorable contacts with the 50S subunit while RRF wedges next to central inter-subunit bridges, illuminating the active roles of tRNA and RRF in dissociation of ribosomal subunits. The structure uncovers a missing snapshot of tRNA as it transits between the P and exit (E) sites, providing insights into the mechanisms of ribosome recycling and tRNA translocation.
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Dégut C, Roovers M, Barraud P, Brachet F, Feller A, Larue V, Al Refaii A, Caillet J, Droogmans L, Tisné C. Structural characterization of B. subtilis m1A22 tRNA methyltransferase TrmK: insights into tRNA recognition. Nucleic Acids Res 2019; 47:4736-4750. [PMID: 30931478 PMCID: PMC6511850 DOI: 10.1093/nar/gkz230] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 03/04/2019] [Accepted: 03/26/2019] [Indexed: 12/21/2022] Open
Abstract
1-Methyladenosine (m1A) is a modified nucleoside found at positions 9, 14, 22 and 58 of tRNAs, which arises from the transfer of a methyl group onto the N1-atom of adenosine. The yqfN gene of Bacillus subtilis encodes the methyltransferase TrmK (BsTrmK) responsible for the formation of m1A22 in tRNA. Here, we show that BsTrmK displays a broad substrate specificity, and methylates seven out of eight tRNA isoacceptor families of B. subtilis bearing an A22. In addition to a non-Watson–Crick base-pair between the target A22 and a purine at position 13, the formation of m1A22 by BsTrmK requires a full-length tRNA with intact tRNA elbow and anticodon stem. We solved the crystal structure of BsTrmK showing an N-terminal catalytic domain harbouring the typical Rossmann-like fold of Class-I methyltransferases and a C-terminal coiled-coil domain. We used NMR chemical shift mapping to drive the docking of BstRNASer to BsTrmK in complex with its methyl-donor cofactor S-adenosyl-L-methionine (SAM). In this model, validated by methyltransferase activity assays on BsTrmK mutants, both domains of BsTrmK participate in tRNA binding. BsTrmK recognises tRNA with very few structural changes in both partner, the non-Watson–Crick R13–A22 base-pair positioning the A22 N1-atom close to the SAM methyl group.
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Affiliation(s)
- Clément Dégut
- Laboratoire de Cristallographie et RMN biologiques, CNRS, Université Paris Descartes, Sorbonne Paris Cité, 4 avenue de l'Observatoire, 75006 Paris, France
| | | | - Pierre Barraud
- Laboratoire de Cristallographie et RMN biologiques, CNRS, Université Paris Descartes, Sorbonne Paris Cité, 4 avenue de l'Observatoire, 75006 Paris, France.,Laboratoire d'Expression génétique microbienne, CNRS, Univ. Paris Diderot, Sorbonne Paris Cité, Institut de Biologie Physico-Chimique, IBPC, 13 rue Pierre et Marie Curie, 75005 Paris, France
| | - Franck Brachet
- Laboratoire de Cristallographie et RMN biologiques, CNRS, Université Paris Descartes, Sorbonne Paris Cité, 4 avenue de l'Observatoire, 75006 Paris, France
| | - André Feller
- Laboratoire de Microbiologie, Université libre de Bruxelles (ULB), 6041 Gosselies, Belgium
| | - Valéry Larue
- Laboratoire de Cristallographie et RMN biologiques, CNRS, Université Paris Descartes, Sorbonne Paris Cité, 4 avenue de l'Observatoire, 75006 Paris, France
| | - Abdalla Al Refaii
- Laboratoire de Microbiologie, Université libre de Bruxelles (ULB), 6041 Gosselies, Belgium
| | - Joël Caillet
- Laboratoire d'Expression génétique microbienne, CNRS, Univ. Paris Diderot, Sorbonne Paris Cité, Institut de Biologie Physico-Chimique, IBPC, 13 rue Pierre et Marie Curie, 75005 Paris, France
| | - Louis Droogmans
- Laboratoire de Microbiologie, Université libre de Bruxelles (ULB), 6041 Gosselies, Belgium
| | - Carine Tisné
- Laboratoire de Cristallographie et RMN biologiques, CNRS, Université Paris Descartes, Sorbonne Paris Cité, 4 avenue de l'Observatoire, 75006 Paris, France.,Laboratoire d'Expression génétique microbienne, CNRS, Univ. Paris Diderot, Sorbonne Paris Cité, Institut de Biologie Physico-Chimique, IBPC, 13 rue Pierre et Marie Curie, 75005 Paris, France
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Regulation of Bacterial Gene Expression by Transcription Attenuation. Microbiol Mol Biol Rev 2019; 83:83/3/e00019-19. [PMID: 31270135 DOI: 10.1128/mmbr.00019-19] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
A wide variety of mechanisms that control gene expression in bacteria are based on conditional transcription termination. Generally, in these mechanisms, a transcription terminator is located between a promoter and a downstream gene(s), and the efficiency of the terminator is controlled by a regulatory effector that can be a metabolite, protein, or RNA. The most common type of regulation involving conditional termination is transcription attenuation, in which the primary regulatory target is an essential element of a single terminator. The terminator can be either intrinsic or Rho dependent, with each presenting unique regulatory targets. Transcription attenuation mechanisms can be divided into five classes based primarily on the manner in which transcription termination is rendered conditional. This review summarizes each class of control mechanisms from a historical perspective, describes important examples in a physiological context and the current state of knowledge, highlights major advances, and discusses expectations of future discoveries.
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39
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Abstract
The T-box riboswitch is a unique, RNA-based regulatory mechanism that modulates expression of a wide variety of amino acid-related genes, predominantly in Firmicutes. RNAs of this class selectively bind a specific cognate tRNA, utilizing recognition of the tRNA anticodon and other tRNA features. The riboswitch monitors the aminoacylation status of the tRNA to induce expression of the regulated downstream gene(s) at the level of transcription antitermination or derepression of translation initiation in response to reduced tRNA charging via stabilization of an antiterminator or antisequestrator. Recent biochemical and structural studies have revealed new features of tRNA recognition that extend beyond the initially identified Watson-Crick base-pairing of a codon-like sequence in the riboswitch with the tRNA anticodon, and residues in the antiterminator or antisequestrator with the tRNA acceptor end. These studies have revealed new tRNA contacts and new modes of riboswitch function and ligand recognition that expand our understanding of RNA-RNA recognition and the biological roles of tRNA.
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40
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The RNA degradosome promotes tRNA quality control through clearance of hypomodified tRNA. Proc Natl Acad Sci U S A 2019; 116:1394-1403. [PMID: 30622183 DOI: 10.1073/pnas.1814130116] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The factors and mechanisms that govern tRNA stability in bacteria are not well understood. Here, we investigated the influence of posttranscriptional modification of bacterial tRNAs (tRNA modification) on tRNA stability. We focused on ThiI-generated 4-thiouridine (s4U), a modification found in bacterial and archaeal tRNAs. Comprehensive quantification of Vibrio cholerae tRNAs revealed that the abundance of some tRNAs is decreased in a ΔthiI strain in a stationary phase-specific manner. Multiple mechanisms, including rapid degradation of a subset of hypomodified tRNAs, account for the reduced abundance of tRNAs in the absence of thiI Through transposon insertion sequencing, we identified additional tRNA modifications that promote tRNA stability and bacterial viability. Genetic analysis of suppressor mutants as well as biochemical analyses revealed that rapid degradation of hypomodified tRNA is mediated by the RNA degradosome. Elongation factor Tu seems to compete with the RNA degradosome, protecting aminoacyl tRNAs from decay. Together, our observations describe a previously unrecognized bacterial tRNA quality control system in which hypomodification sensitizes tRNAs to decay mediated by the RNA degradosome.
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41
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Structural Basis for tRNA Mimicry by a Bacterial Y RNA. Structure 2018; 26:1635-1644.e3. [PMID: 30318468 DOI: 10.1016/j.str.2018.09.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 07/03/2018] [Accepted: 09/10/2018] [Indexed: 12/29/2022]
Abstract
Noncoding Y RNAs are present in both animal cells and many bacteria. In all species examined, Y RNAs tether the Ro60 protein to an effector protein to perform various cellular functions. Recently, a new Y RNA subfamily was identified in bacteria. Bioinformatic analyses of these YrlA (Y RNA-like A) RNAs predict that the effector-binding domain resembles tRNA. We present the structure of this domain, the overall folding of which is strikingly similar to canonical tRNAs. The tertiary interactions that are responsible for stabilizing tRNA are present in YrlA, making it a close tRNA mimic. However, YrlA lacks a free CCA end and contains a kink in the stem corresponding to the anticodon stem. Since nucleotides in the D and T stems are conserved among YrlAs, they may be an interaction site for an unknown factor. Our experiments identify YrlA RNAs as a new class of tRNA mimics.
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42
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Thornlow BP, Hough J, Roger JM, Gong H, Lowe TM, Corbett-Detig RB. Transfer RNA genes experience exceptionally elevated mutation rates. Proc Natl Acad Sci U S A 2018; 115:8996-9001. [PMID: 30127029 PMCID: PMC6130373 DOI: 10.1073/pnas.1801240115] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Transfer RNAs (tRNAs) are a central component for the biological synthesis of proteins, and they are among the most highly conserved and frequently transcribed genes in all living things. Despite their clear significance for fundamental cellular processes, the forces governing tRNA evolution are poorly understood. We present evidence that transcription-associated mutagenesis and strong purifying selection are key determinants of patterns of sequence variation within and surrounding tRNA genes in humans and diverse model organisms. Remarkably, the mutation rate at broadly expressed cytosolic tRNA loci is likely between 7 and 10 times greater than the nuclear genome average. Furthermore, evolutionary analyses provide strong evidence that tRNA genes, but not their flanking sequences, experience strong purifying selection acting against this elevated mutation rate. We also find a strong correlation between tRNA expression levels and the mutation rates in their immediate flanking regions, suggesting a simple method for estimating individual tRNA gene activity. Collectively, this study illuminates the extreme competing forces in tRNA gene evolution and indicates that mutations at tRNA loci contribute disproportionately to mutational load and have unexplored fitness consequences in human populations.
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Affiliation(s)
- Bryan P Thornlow
- Department of Biomolecular Engineering, University of California, Santa Cruz, CA 95064
| | - Josh Hough
- Department of Biomolecular Engineering, University of California, Santa Cruz, CA 95064
| | - Jacquelyn M Roger
- Department of Biomolecular Engineering, University of California, Santa Cruz, CA 95064
| | - Henry Gong
- Department of Biomolecular Engineering, University of California, Santa Cruz, CA 95064
| | - Todd M Lowe
- Department of Biomolecular Engineering, University of California, Santa Cruz, CA 95064;
- Genomics Institute, University of California, Santa Cruz, CA 95064
| | - Russell B Corbett-Detig
- Department of Biomolecular Engineering, University of California, Santa Cruz, CA 95064;
- Genomics Institute, University of California, Santa Cruz, CA 95064
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Borriss R, Danchin A, Harwood CR, Médigue C, Rocha EP, Sekowska A, Vallenet D. Bacillus subtilis, the model Gram-positive bacterium: 20 years of annotation refinement. Microb Biotechnol 2018; 11:3-17. [PMID: 29280348 PMCID: PMC5743806 DOI: 10.1111/1751-7915.13043] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Genome annotation is, nowadays, performed via automatic pipelines that cannot discriminate between right and wrong annotations. Given their importance in increasing the accuracy of the genome annotations of other organisms, it is critical that the annotations of model organisms reflect the current annotation gold standard. The genome of Bacillus subtilis strain 168 was sequenced twenty years ago. Using a combination of inductive, deductive and abductive reasoning, we present a unique, manually curated annotation, essentially based on experimental data. This reveals how this bacterium lives in a plant niche, while carrying a paleome operating system common to Firmicutes and Tenericutes. Dozens of new genomic objects and an extensive literature survey have been included for the sequence available at the INSDC (AccNum AL009126.3). We also propose an extension to Demerec's nomenclature rules that will help investigators connect to this type of curated annotation via the use of common gene names.
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Affiliation(s)
- Rainer Borriss
- Department of PhytomedicineHumboldt‐Universität zu BerlinLentzeallee 55‐5714195BerlinGermany
| | - Antoine Danchin
- Hôpital de la Pitié‐SalpêtrièreInstitute of Cardiometabolism and Nutrition47 Boulevard de l'Hôpital75013ParisFrance
- School of Biomedical SciencesLi Kashing Faculty of MedicineUniversity of Hong Kong21 Sassoon RoadPok Fu LamSAR Hong KongChina
| | - Colin R. Harwood
- The Centre for Bacterial Cell BiologyNewcastle UniversityBaddiley‐Clark BuildingRichardson RoadNewcastle upon TyneNE2 4AXUK
| | - Claudine Médigue
- CEA DRF Genoscope LABGeMCNRS, UMR8030 Génomique MétaboliqueUniversité d'Evry Val d'EssonneUniversité Paris‐SaclayF‐91057EvryFrance
| | - Eduardo P.C. Rocha
- Microbial Evolutionary Genomics UnitInstitut Pasteur28 rue du Docteur Roux75724Paris Cedex 15France
| | - Agnieszka Sekowska
- Hôpital de la Pitié‐SalpêtrièreInstitute of Cardiometabolism and Nutrition47 Boulevard de l'Hôpital75013ParisFrance
| | - David Vallenet
- CEA DRF Genoscope LABGeMCNRS, UMR8030 Génomique MétaboliqueUniversité d'Evry Val d'EssonneUniversité Paris‐SaclayF‐91057EvryFrance
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Ariza-Mateos A, Gómez J. Viral tRNA Mimicry from a Biocommunicative Perspective. Front Microbiol 2017; 8:2395. [PMID: 29259593 PMCID: PMC5723415 DOI: 10.3389/fmicb.2017.02395] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 11/20/2017] [Indexed: 12/20/2022] Open
Abstract
RNA viruses have very small genomes which limits the functions they can encode. One of the strategies employed by these viruses is to mimic key factors of the host cell so they can take advantage of the interactions and activities these factors typically participate in. The viral RNA genome itself was first observed to mimic cellular tRNA over 40 years ago. Since then researchers have confirmed that distinct families of RNA viruses are accessible to a battery of cellular factors involved in tRNA-related activities. Recently, potential tRNA-like structures have been detected within the sequences of a 100 mRNAs taken from human cells, one of these being the host defense interferon-alpha mRNA; these are then additional to the examples found in bacterial and yeast mRNAs. The mimetic relationship between tRNA, cellular mRNA, and viral RNA is the central focus of two considerations described below. These are subsequently used as a preface for a final hypothesis drawing on concepts relating to mimicry from the social sciences and humanities, such as power relations and creativity. Firstly, the presence of tRNA-like structures in mRNAs indicates that the viral tRNA-like signal could be mimicking tRNA-like elements that are contextualized by the specific carrier mRNAs, rather than, or in addition to, the tRNA itself, which would significantly increase the number of potential semiotic relations mediated by the viral signals. Secondly, and in particular, mimicking a host defense mRNA could be considered a potential new viral strategy for survival. Finally, we propose that mRNA's mimicry of tRNA could be indicative of an ancestral intracellular conflict in which species of mRNAs invaded the cell, but from within. As the meaning of the mimetic signal depends on the context, in this case, the conflict that arises when the viral signal enters the cell can change the meaning of the mRNAs' internal tRNA-like signals, from their current significance to that they had in the distant past.
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Affiliation(s)
- Ascensión Ariza-Mateos
- Laboratory of RNA Archaeology, Instituto de Parasitología y Biomedicina “López Neyra” (Consejo Superior de Investigaciones Científicas), Granada, Spain
- Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, Madrid, Spain
| | - Jordi Gómez
- Laboratory of RNA Archaeology, Instituto de Parasitología y Biomedicina “López Neyra” (Consejo Superior de Investigaciones Científicas), Granada, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Madrid, Spain
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45
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Klemm BP, Karasik A, Kaitany KJ, Shanmuganathan A, Henley MJ, Thelen AZ, Dewar AJL, Jackson ND, Koutmos M, Fierke CA. Molecular recognition of pre-tRNA by Arabidopsis protein-only Ribonuclease P. RNA (NEW YORK, N.Y.) 2017; 23:1860-1873. [PMID: 28874505 PMCID: PMC5689006 DOI: 10.1261/rna.061457.117] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 08/31/2017] [Indexed: 05/06/2023]
Abstract
Protein-only ribonuclease P (PRORP) is an enzyme responsible for catalyzing the 5' end maturation of precursor transfer ribonucleic acids (pre-tRNAs) encoded by various cellular compartments in many eukaryotes. PRORPs from plants act as single-subunit enzymes and have been used as a model system for analyzing the function of the metazoan PRORP nuclease subunit, which requires two additional proteins for efficient catalysis. There are currently few molecular details known about the PRORP-pre-tRNA complex. Here, we characterize the determinants of substrate recognition by the single subunit Arabidopsis thaliana PRORP1 and PRORP2 using kinetic and thermodynamic experiments. The salt dependence of binding affinity suggests 4-5 contacts with backbone phosphodiester bonds on substrates, including a single phosphodiester contact with the pre-tRNA 5' leader, consistent with prior reports of short leader requirements. PRORPs contain an N-terminal pentatricopeptide repeat (PPR) domain, truncation of which results in a >30-fold decrease in substrate affinity. While most PPR-containing proteins have been implicated in single-stranded sequence-specific RNA recognition, we find that the PPR motifs of PRORPs recognize pre-tRNA substrates differently. Notably, the PPR domain residues most important for substrate binding in PRORPs do not correspond to positions involved in base recognition in other PPR proteins. Several of these residues are highly conserved in PRORPs from algae, plants, and metazoans, suggesting a conserved strategy for substrate recognition by the PRORP PPR domain. Furthermore, there is no evidence for sequence-specific interactions. This work clarifies molecular determinants of PRORP-substrate recognition and provides a new predictive model for the PRORP-substrate complex.
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Affiliation(s)
- Bradley P Klemm
- Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Agnes Karasik
- Department of Biochemistry and Molecular Biology, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, USA
| | - Kipchumba J Kaitany
- Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Aranganathan Shanmuganathan
- Department of Biochemistry and Molecular Biology, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, USA
| | - Matthew J Henley
- Program in Chemical Biology, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Adam Z Thelen
- Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Allison J L Dewar
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Nathaniel D Jackson
- Department of Biochemistry and Molecular Biology, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, USA
| | - Markos Koutmos
- Department of Biochemistry and Molecular Biology, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, USA
| | - Carol A Fierke
- Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA
- Program in Chemical Biology, University of Michigan, Ann Arbor, Michigan 48109, USA
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA
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46
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Stamatopoulou V, Apostolidi M, Li S, Lamprinou K, Papakyriakou A, Zhang J, Stathopoulos C. Direct modulation of T-box riboswitch-controlled transcription by protein synthesis inhibitors. Nucleic Acids Res 2017; 45:10242-10258. [PMID: 28973457 PMCID: PMC5622331 DOI: 10.1093/nar/gkx663] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 07/18/2017] [Indexed: 11/14/2022] Open
Abstract
Recently, it was discovered that exposure to mainstream antibiotics activate numerous bacterial riboregulators that control antibiotic resistance genes including metabolite-binding riboswitches and other transcription attenuators. However, the effects of commonly used antibiotics, many of which exhibit RNA-binding properties, on the widespread T-box riboswitches, remain unknown. In Staphylococcus aureus, a species-specific glyS T-box controls the supply of glycine for both ribosomal translation and cell wall synthesis, making it a promising target for next-generation antimicrobials. Here, we report that specific protein synthesis inhibitors could either significantly increase T-box-mediated transcription antitermination, while other compounds could suppress it, both in vitro and in vivo. In-line probing of the full-length T-box combined with molecular modelling and docking analyses suggest that the antibiotics that promote transcription antitermination stabilize the T-box:tRNA complex through binding specific positions on stem I and the Staphylococcal-specific stem Sa. By contrast, the antibiotics that attenuate T-box transcription bind to other positions on stem I and do not interact with stem Sa. Taken together, our results reveal that the transcription of essential genes controlled by T-box riboswitches can be directly modulated by commonly used protein synthesis inhibitors. These findings accentuate the regulatory complexities of bacterial response to antimicrobials that involve multiple riboregulators.
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Affiliation(s)
| | - Maria Apostolidi
- Department of Biochemistry, School of Medicine, University of Patras, 26504 Patras, Greece
| | - Shuang Li
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, 50 South Drive, Bethesda, MD 20892, USA
| | - Katerina Lamprinou
- Department of Biochemistry, School of Medicine, University of Patras, 26504 Patras, Greece
| | - Athanasios Papakyriakou
- Institute of Biosciences and Applications, National Centre for Scientific Research 'Demokritos', Athens, Greece
| | - Jinwei Zhang
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, 50 South Drive, Bethesda, MD 20892, USA
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47
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Pak D, Root-Bernstein R, Burton ZF. tRNA structure and evolution and standardization to the three nucleotide genetic code. Transcription 2017. [PMID: 28632998 PMCID: PMC5574529 DOI: 10.1080/21541264.2017.1318811] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Cloverleaf tRNA with a 75 nucleotide (nt) core is posited to have evolved from ligation of three 31 nt minihelices followed by symmetric internal deletions of 9 nt within ligated acceptor stems. Statistical tests strongly support the model. Although the tRNA anticodon loop and T loop are homologs, their U-turns have been treated as distinct motifs. An appropriate comparison, however, shows that intercalation of D loop G19 between T loop bases 4 and 5 causes elevation of T loop base 5 and flipping of T loop bases 6 and 7 out of the 7 nt loop. In the anticodon loop, by contrast, loop bases 3–7 stack tightly to form a stiff connection to mRNA. Furthermore, we identify ancient repeat sequences of 3 (GCG), 5 (UAGCC) and 17 nt (∼CCGGGUUCAAAACCCGG) that comprise 75 out of 75 nts of the tRNA cloverleaf core. To present a sufficiently stiff 3-nt anticodon, a 7-nt anticodon loop was necessary with a U-turn between loop positions 2 and 3. Cloverleaf tRNA, therefore, was a radical evolutionary innovation essential for the 3-nt code. Conservation of GCG and UAGCC repeat sequences indicates that cloverleaf tRNA is at the interface between a strange RNA repeat world and the first evolution of molecules that fold to assume biologic functions. We posit that cloverleaf tRNA was the molecular archetype around which translation systems evolved.
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Affiliation(s)
- Daewoo Pak
- a Center for Statistical Training and Consulting , Michigan State University , East Lansing , MI , USA
| | | | - Zachary F Burton
- c Department of Biochemistry and Molecular Biology , Michigan State University , MI , USA
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Monestier A, Aleksandrov A, Coureux PD, Panvert M, Mechulam Y, Schmitt E. The structure of an E. coli tRNA fMet A 1-U 72 variant shows an unusual conformation of the A 1-U 72 base pair. RNA (NEW YORK, N.Y.) 2017; 23:673-682. [PMID: 28143889 PMCID: PMC5393177 DOI: 10.1261/rna.057877.116] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 01/26/2017] [Indexed: 06/06/2023]
Abstract
Translation initiation in eukaryotes and archaea involves a methionylated initiator tRNA delivered to the ribosome in a ternary complex with e/aIF2 and GTP. Eukaryotic and archaeal initiator tRNAs contain a highly conserved A1-U72 base pair at the top of the acceptor stem. The importance of this base pair to discriminate initiator tRNAs from elongator tRNAs has been established previously using genetics and biochemistry. However, no structural data illustrating how the A1-U72 base pair participates in the accurate selection of the initiator tRNAs by the translation initiation systems are available. Here, we describe the crystal structure of a mutant E. coli initiator tRNAfMetA1-U72, aminoacylated with methionine, in which the C1:A72 mismatch at the end of the tRNA acceptor stem has been changed to an A1-U72 base pair. Sequence alignments show that the mutant E. coli tRNA is a good mimic of archaeal initiator tRNAs. The crystal structure, determined at 2.8 Å resolution, shows that the A1-U72 pair adopts an unusual arrangement. A1 is in a syn conformation and forms a single H-bond interaction with U72 This interaction requires protonation of the N1 atom of A1 Moreover, the 5' phosphoryl group folds back into the major groove of the acceptor stem and interacts with the N7 atom of G2 A possible role of this unusual geometry of the A1-U72 pair in the recognition of the initiator tRNA by its partners during eukaryotic and archaeal translation initiation is discussed.
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Affiliation(s)
- Auriane Monestier
- Laboratoire de Biochimie, Ecole polytechnique, CNRS, Université Paris-Saclay, 91128 Palaiseau cedex, France
| | - Alexey Aleksandrov
- Laboratoire de Biochimie, Ecole polytechnique, CNRS, Université Paris-Saclay, 91128 Palaiseau cedex, France
| | - Pierre-Damien Coureux
- Laboratoire de Biochimie, Ecole polytechnique, CNRS, Université Paris-Saclay, 91128 Palaiseau cedex, France
| | - Michel Panvert
- Laboratoire de Biochimie, Ecole polytechnique, CNRS, Université Paris-Saclay, 91128 Palaiseau cedex, France
| | - Yves Mechulam
- Laboratoire de Biochimie, Ecole polytechnique, CNRS, Université Paris-Saclay, 91128 Palaiseau cedex, France
| | - Emmanuelle Schmitt
- Laboratoire de Biochimie, Ecole polytechnique, CNRS, Université Paris-Saclay, 91128 Palaiseau cedex, France
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49
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Abstract
All types of nucleic acids in cells undergo naturally occurring chemical modifications, including DNA, rRNA, mRNA, snRNA, and most prominently tRNA. Over 100 different modifications have been described and every position in the purine and pyrimidine bases can be modified; often the sugar is also modified [1]. In tRNA, the function of modifications varies; some modulate global and/or local RNA structure, and others directly impact decoding and may be essential for viability. Whichever the case, the overall importance of modifications is highlighted by both their evolutionary conservation and the fact that organisms use a substantial portion of their genomes to encode modification enzymes, far exceeding what is needed for the de novo synthesis of the canonical nucleotides themselves [2]. Although some modifications occur at exactly the same nucleotide position in tRNAs from the three domains of life, many can be found at various positions in a particular tRNA and their location may vary between and within different tRNAs. With this wild array of chemical diversity and substrate specificities, one of the big challenges in the tRNA modification field has been to better understand at a molecular level the modes of substrate recognition by the different modification enzymes; in this realm RNA binding rests at the heart of the problem. This chapter will focus on several examples of modification enzymes where their mode of RNA binding is well understood; from these, we will try to draw general conclusions and highlight growing themes that may be applicable to the RNA modification field at large.
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50
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Lorenz C, Lünse CE, Mörl M. tRNA Modifications: Impact on Structure and Thermal Adaptation. Biomolecules 2017; 7:E35. [PMID: 28375166 PMCID: PMC5485724 DOI: 10.3390/biom7020035] [Citation(s) in RCA: 216] [Impact Index Per Article: 30.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2017] [Revised: 03/27/2017] [Accepted: 03/28/2017] [Indexed: 12/27/2022] Open
Abstract
Transfer RNAs (tRNAs) are central players in translation, functioning as adapter molecules between the informational level of nucleic acids and the functional level of proteins. They show a highly conserved secondary and tertiary structure and the highest density of post-transcriptional modifications among all RNAs. These modifications concentrate in two hotspots-the anticodon loop and the tRNA core region, where the D- and T-loop interact with each other, stabilizing the overall structure of the molecule. These modifications can cause large rearrangements as well as local fine-tuning in the 3D structure of a tRNA. The highly conserved tRNA shape is crucial for the interaction with a variety of proteins and other RNA molecules, but also needs a certain flexibility for a correct interplay. In this context, it was shown that tRNA modifications are important for temperature adaptation in thermophilic as well as psychrophilic organisms, as they modulate rigidity and flexibility of the transcripts, respectively. Here, we give an overview on the impact of modifications on tRNA structure and their importance in thermal adaptation.
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Affiliation(s)
- Christian Lorenz
- Institute of Biochemistry, Leipzig University, Brüderstraße 34, 04103 Leipzig, Germany.
| | - Christina E Lünse
- Institute of Biochemistry, Leipzig University, Brüderstraße 34, 04103 Leipzig, Germany.
| | - Mario Mörl
- Institute of Biochemistry, Leipzig University, Brüderstraße 34, 04103 Leipzig, Germany.
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