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Harrison BR, Lee MB, Zhang S, Young B, Han K, Sukomol J, Paus V, Tran S, Kim D, Fitchett H, Pan YC, Tesfaye P, Johnson AW, Zhao X, Djukovic D, Raftery D, Promislow DEL. Wide-ranging genetic variation in sensitivity to rapamycin in Drosophila melanogaster. Aging Cell 2024:e14292. [PMID: 39135281 DOI: 10.1111/acel.14292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Revised: 06/18/2024] [Accepted: 07/16/2024] [Indexed: 09/05/2024] Open
Abstract
The progress made in aging research using laboratory organisms is undeniable. Yet, with few exceptions, these studies are conducted in a limited number of isogenic strains. The path from laboratory discoveries to treatment in human populations is complicated by the reality of genetic variation in nature. To model the effect of genetic variation on the action of the drug rapamycin, here we use the growth of Drosophila melanogaster larvae. We screened 140 lines from the Drosophila Genetic References Panel for the extent of developmental delay and found wide-ranging variation in their response, from lines whose development time is nearly doubled by rapamycin, to those that appear to be completely resistant. Sensitivity did not associate with any single genetic marker, nor with any gene. However, variation at the level of genetic pathways was associated with rapamycin sensitivity and might provide insight into sensitivity. In contrast to the genetic analysis, metabolomic analysis showed a strong response of the metabolome to rapamycin, but only among the sensitive larvae. In particular, we found that rapamycin altered levels of amino acids in sensitive larvae, and in a direction strikingly similar to the metabolome response to nutrient deprivation. This work demonstrates the need to evaluate interventions across genetic backgrounds and highlights the potential of omic approaches to reveal biomarkers of drug efficacy and to shed light on mechanisms underlying sensitivity to interventions aimed at increasing lifespan.
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Affiliation(s)
- Benjamin R Harrison
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, USA
| | | | - Shufan Zhang
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Bill Young
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Kenneth Han
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Jiranut Sukomol
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Vanessa Paus
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Sarina Tran
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, USA
| | - David Kim
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Hannah Fitchett
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Yu-Chen Pan
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Philmon Tesfaye
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Alia W Johnson
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Xiaqing Zhao
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Danijel Djukovic
- Northwest Metabolomics Research Center, Department of Anesthesiology and Pain Medicine, University of Washington School of Medicine, Seattle, Washington, USA
| | - Daniel Raftery
- Northwest Metabolomics Research Center, Department of Anesthesiology and Pain Medicine, University of Washington School of Medicine, Seattle, Washington, USA
| | - Daniel E L Promislow
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, USA
- Department of Biology, University of Washington, Seattle, Washington, USA
- Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, Boston, Massachusetts, USA
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2
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Böttcher B, Kienast SD, Leufken J, Eggers C, Sharma P, Leufken CM, Morgner B, Drexler HCA, Schulz D, Allert S, Jacobsen ID, Vylkova S, Leidel SA, Brunke S. A highly conserved tRNA modification contributes to C. albicans filamentation and virulence. Microbiol Spectr 2024; 12:e0425522. [PMID: 38587411 PMCID: PMC11064501 DOI: 10.1128/spectrum.04255-22] [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: 10/18/2022] [Accepted: 01/18/2024] [Indexed: 04/09/2024] Open
Abstract
tRNA modifications play important roles in maintaining translation accuracy in all domains of life. Disruptions in the tRNA modification machinery, especially of the anticodon stem loop, can be lethal for many bacteria and lead to a broad range of phenotypes in baker's yeast. Very little is known about the function of tRNA modifications in host-pathogen interactions, where rapidly changing environments and stresses require fast adaptations. We found that two closely related fungal pathogens of humans, the highly pathogenic Candida albicans and its much less pathogenic sister species, Candida dubliniensis, differ in the function of a tRNA-modifying enzyme. This enzyme, Hma1, exhibits species-specific effects on the ability of the two fungi to grow in the hypha morphology, which is central to their virulence potential. We show that Hma1 has tRNA-threonylcarbamoyladenosine dehydratase activity, and its deletion alters ribosome occupancy, especially at 37°C-the body temperature of the human host. A C. albicans HMA1 deletion mutant also shows defects in adhesion to and invasion into human epithelial cells and shows reduced virulence in a fungal infection model. This links tRNA modifications to host-induced filamentation and virulence of one of the most important fungal pathogens of humans.IMPORTANCEFungal infections are on the rise worldwide, and their global burden on human life and health is frequently underestimated. Among them, the human commensal and opportunistic pathogen, Candida albicans, is one of the major causative agents of severe infections. Its virulence is closely linked to its ability to change morphologies from yeasts to hyphae. Here, this ability is linked-to our knowledge for the first time-to modifications of tRNA and translational efficiency. One tRNA-modifying enzyme, Hma1, plays a specific role in C. albicans and its ability to invade the host. This adds a so-far unknown layer of regulation to the fungal virulence program and offers new potential therapeutic targets to fight fungal infections.
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Affiliation(s)
- Bettina Böttcher
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
- Septomics Research Center, Friedrich Schiller University and Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
| | - Sandra D. Kienast
- Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, Münster, Germany
- Research Group for Cellular RNA Biochemistry, Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Johannes Leufken
- Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, Münster, Germany
- Research Group for Cellular RNA Biochemistry, Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Cristian Eggers
- Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, Münster, Germany
- Research Group for Cellular RNA Biochemistry, Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Puneet Sharma
- Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, Münster, Germany
- Research Group for Cellular RNA Biochemistry, Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Christine M. Leufken
- Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| | - Bianka Morgner
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
| | - Hannes C. A. Drexler
- Bioanalytical Mass Spectrometry Unit, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| | - Daniela Schulz
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
| | - Stefanie Allert
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
| | - Ilse D. Jacobsen
- Research Group Microbial Immunology, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
- Institute of Microbiology, Friedrich Schiller University, Jena, Germany
| | - Slavena Vylkova
- Septomics Research Center, Friedrich Schiller University and Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
| | - Sebastian A. Leidel
- Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, Münster, Germany
- Research Group for Cellular RNA Biochemistry, Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Sascha Brunke
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
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3
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Molina E, Cataldo VF, Eggers C, Muñoz-Madrid V, Glavic Á. p53 Related Protein Kinase is Required for Arp2/3-Dependent Actin Dynamics of Hemocytes in Drosophila melanogaster. Front Cell Dev Biol 2022; 10:859105. [PMID: 35721516 PMCID: PMC9201722 DOI: 10.3389/fcell.2022.859105] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 04/22/2022] [Indexed: 11/21/2022] Open
Abstract
Cells extend membrane protrusions like lamellipodia and filopodia from the leading edge to sense, to move and to form new contacts. The Arp2/3 complex sustains lamellipodia formation, and in conjunction with the actomyosin contractile system, provides mechanical strength to the cell. Drosophila p53-related protein kinase (Prpk), a Tsc5p ortholog, has been described as essential for cell growth and proliferation. In addition, Prpk interacts with proteins associated to actin filament dynamics such as α-spectrin and the Arp2/3 complex subunit Arpc4. Here, we investigated the role of Prpk in cell shape changes, specifically regarding actin filament dynamics and membrane protrusion formation. We found that reductions in Prpk alter cell shape and the structure of lamellipodia, mimicking the phenotypes evoked by Arp2/3 complex deficiencies. Prpk co-localize and co-immunoprecipitates with the Arp2/3 complex subunit Arpc1 and with the small GTPase Rab35. Importantly, expression of Rab35, known by its ability to recruit upstream regulators of the Arp2/3 complex, could rescue the Prpk knockdown phenotypes. Finally, we evaluated the requirement of Prpk in different developmental contexts, where it was shown to be essential for correct Arp2/3 complex distribution and actin dynamics required for hemocytes migration, recruitment, and phagocytosis during immune response.
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Affiliation(s)
- Emiliano Molina
- FONDAP Center for Genome Regulation, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
| | - Vicente F. Cataldo
- Department of Chemical and Bioprocess Engineering, School of Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Cristián Eggers
- Department for Chemistry and Biochemistry and Pharmaceutical Sciences, Faculty of Science, University of Bern, Bern, Switzerland
| | - Valentina Muñoz-Madrid
- FONDAP Center for Genome Regulation, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
| | - Álvaro Glavic
- FONDAP Center for Genome Regulation, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
- *Correspondence: Álvaro Glavic,
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4
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Kelley M, Paulines MJ, Yoshida G, Myers R, Jora M, Levoy JP, Addepalli B, Benoit JB, Limbach PA. Ionizing radiation and chemical oxidant exposure impacts on Cryptococcus neoformans transfer RNAs. PLoS One 2022; 17:e0266239. [PMID: 35349591 PMCID: PMC8963569 DOI: 10.1371/journal.pone.0266239] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 03/16/2022] [Indexed: 12/11/2022] Open
Abstract
Cryptococcus neoformans is a fungus that is able to survive abnormally high levels of ionizing radiation (IR). The radiolysis of water by IR generates reactive oxygen species (ROS) such as H2O2 and OH-. C. neoformans withstands the damage caused by IR and ROS through antioxidant production and enzyme-catalyzed breakdown of ROS. Given these particular cellular protein needs, questions arise whether transfer ribonucleic acids molecules (tRNAs) undergo unique chemical modifications to maintain their structure, stability, and/or function under such environmental conditions. Here, we investigated the effects of IR and H2O2 exposure on tRNAs in C. neoformans. We experimentally identified the modified nucleosides present in C. neoformans tRNAs and quantified changes in those modifications upon exposure to oxidative conditions. To better understand these modified nucleoside results, we also evaluated tRNA pool composition in response to the oxidative conditions. We found that regardless of environmental conditions, tRNA modifications and transcripts were minimally affected. A rationale for the stability of the tRNA pool and its concomitant profile of modified nucleosides is proposed based on the lack of codon bias throughout the C. neoformans genome and in particular for oxidative response transcripts. Our findings suggest that C. neoformans can rapidly adapt to oxidative environments as mRNA translation/protein synthesis are minimally impacted by codon bias.
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Affiliation(s)
- Melissa Kelley
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio, United States of America
| | - Mellie June Paulines
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio, United States of America
| | - George Yoshida
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio, United States of America
| | - Ryan Myers
- Department of Biological Sciences, University of Cincinnati, Cincinnati, Ohio, United States of America
| | - Manasses Jora
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio, United States of America
| | - Joel P. Levoy
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio, United States of America
| | | | - Joshua B. Benoit
- Department of Biological Sciences, University of Cincinnati, Cincinnati, Ohio, United States of America
| | - Patrick A. Limbach
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio, United States of America
- * E-mail:
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5
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Khalique A, Mattijssen S, Maraia RJ. A versatile tRNA modification-sensitive northern blot method with enhanced performance. RNA (NEW YORK, N.Y.) 2022; 28:418-432. [PMID: 34930808 PMCID: PMC8848930 DOI: 10.1261/rna.078929.121] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 12/01/2021] [Indexed: 06/14/2023]
Abstract
The 22 mitochondrial and ∼45 cytosolic tRNAs in human cells contain several dozen different post-transcriptional modified nucleotides such that each carries a unique constellation that complements its function. Many tRNA modifications are linked to altered gene expression, and deficiencies due to mutations in tRNA modification enzymes (TMEs) are responsible for numerous diseases. Easily accessible methods to detect tRNA hypomodifications can facilitate progress in advancing such molecular studies. Our laboratory developed a northern blot method that can quantify relative levels of base modifications on multiple specific tRNAs ∼10 yr ago, which has been used to characterize four different TME deficiencies and is likely further extendable. The assay method depends on differential annealing efficiency of a DNA-oligo probe to the modified versus unmodified tRNA. The signal of this probe is then normalized by a second probe elsewhere on the same tRNA. This positive hybridization in the absence of modification (PHAM) assay has proven useful for i6A37, t6A37, m3C32, and m2,2G26 in multiple laboratories. Yet, over the years we have observed idiosyncratic inconsistency and variability in the assay. Here we document these for some tRNAs and probes and illustrate principles and practices for improved reliability and uniformity in performance. We provide an overview of the method and illustrate benefits of the improved conditions. This is followed by data that demonstrate quantitative validation of PHAM using a TME deletion control, and that nearby modifications can falsely alter the calculated apparent modification efficiency. Finally, we include a calculator tool for matching probe and hybridization conditions.
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Affiliation(s)
- Abdul Khalique
- Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Sandy Mattijssen
- Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Richard J Maraia
- Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA
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6
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Beenstock J, Sicheri F. The structural and functional workings of KEOPS. Nucleic Acids Res 2021; 49:10818-10834. [PMID: 34614169 PMCID: PMC8565320 DOI: 10.1093/nar/gkab865] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 09/09/2021] [Accepted: 10/04/2021] [Indexed: 11/14/2022] Open
Abstract
KEOPS (Kinase, Endopeptidase and Other Proteins of Small size) is a five-subunit protein complex that is highly conserved in eukaryotes and archaea and is essential for the fitness of cells and for animal development. In humans, mutations in KEOPS genes underlie Galloway-Mowat syndrome, which manifests in severe microcephaly and renal dysfunction that lead to childhood death. The Kae1 subunit of KEOPS catalyzes the universal and essential tRNA modification N6-threonylcarbamoyl adenosine (t6A), while the auxiliary subunits Cgi121, the kinase/ATPase Bud32, Pcc1 and Gon7 play a supporting role. Kae1 orthologs are also present in bacteria and mitochondria but function in distinct complexes with proteins that are not related in structure or function to the auxiliary subunits of KEOPS. Over the past 15 years since its discovery, extensive study in the KEOPS field has provided many answers towards understanding the roles that KEOPS plays in cells and in human disease and how KEOPS carries out these functions. In this review, we provide an overview into recent advances in the study of KEOPS and illuminate exciting future directions.
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Affiliation(s)
- Jonah Beenstock
- The Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, M5G 1X5, Canada
| | - Frank Sicheri
- The Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, M5G 1X5, Canada.,Department of Molecular Genetics, University of Toronto, Ontario, M5S 1A8, Canada.,Department of Biochemistry, University of Toronto, Ontario, M5S 1A8, Canada
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7
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Dannfald A, Favory JJ, Deragon JM. Variations in transfer and ribosomal RNA epitranscriptomic status can adapt eukaryote translation to changing physiological and environmental conditions. RNA Biol 2021; 18:4-18. [PMID: 34159889 PMCID: PMC8677040 DOI: 10.1080/15476286.2021.1931756] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 05/07/2021] [Accepted: 05/13/2021] [Indexed: 01/27/2023] Open
Abstract
The timely reprogramming of gene expression in response to internal and external cues is essential to eukaryote development and acclimation to changing environments. Chemically modifying molecular receptors and transducers of these signals is one way to efficiently induce proper physiological responses. Post-translation modifications, regulating protein biological activities, are central to many well-known signal-responding pathways. Recently, messenger RNA (mRNA) chemical (i.e. epitranscriptomic) modifications were also shown to play a key role in these processes. In contrast, transfer RNA (tRNA) and ribosomal RNA (rRNA) chemical modifications, although critical for optimal function of the translation apparatus, and much more diverse and quantitatively important compared to mRNA modifications, were until recently considered as mainly static chemical decorations. We present here recent observations that are challenging this view and supporting the hypothesis that tRNA and rRNA modifications dynamically respond to various cell and environmental conditions and contribute to adapt translation to these conditions.
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Affiliation(s)
- Arnaud Dannfald
- CNRS LGDP-UMR5096, Pepignan, France
- Université de Perpignan via Domitia, Perpignan, France
| | - Jean-Jacques Favory
- CNRS LGDP-UMR5096, Pepignan, France
- Université de Perpignan via Domitia, Perpignan, France
| | - Jean-Marc Deragon
- CNRS LGDP-UMR5096, Pepignan, France
- Université de Perpignan via Domitia, Perpignan, France
- Institut Universitaire de France, Paris, France
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8
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Masuda I, Hwang JY, Christian T, Maharjan S, Mohammad F, Gamper H, Buskirk AR, Hou YM. Loss of N1-methylation of G37 in tRNA induces ribosome stalling and reprograms gene expression. eLife 2021; 10:70619. [PMID: 34382933 PMCID: PMC8384417 DOI: 10.7554/elife.70619] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Accepted: 08/09/2021] [Indexed: 01/20/2023] Open
Abstract
N1-methylation of G37 is required for a subset of tRNAs to maintain the translational reading-frame. While loss of m1G37 increases ribosomal +1 frameshifting, whether it incurs additional translational defects is unknown. Here, we address this question by applying ribosome profiling to gain a genome-wide view of the effects of m1G37 deficiency on protein synthesis. Using E coli as a model, we show that m1G37 deficiency induces ribosome stalling at codons that are normally translated by m1G37-containing tRNAs. Stalling occurs during decoding of affected codons at the ribosomal A site, indicating a distinct mechanism than that of +1 frameshifting, which occurs after the affected codons leave the A site. Enzyme- and cell-based assays show that m1G37 deficiency reduces tRNA aminoacylation and in some cases peptide-bond formation. We observe changes of gene expression in m1G37 deficiency similar to those in the stringent response that is typically induced by deficiency of amino acids. This work demonstrates a previously unrecognized function of m1G37 that emphasizes its role throughout the entire elongation cycle of protein synthesis, providing new insight into its essentiality for bacterial growth and survival.
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Affiliation(s)
- Isao Masuda
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, United States
| | - Jae-Yeon Hwang
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Thomas Christian
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, United States
| | - Sunita Maharjan
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, United States
| | - Fuad Mohammad
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Howard Gamper
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, United States
| | - Allen R Buskirk
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Ya-Ming Hou
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, United States
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9
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Warren JM, Salinas-Giegé T, Hummel G, Coots NL, Svendsen JM, Brown KC, Drouard L, Sloan DB. Combining tRNA sequencing methods to characterize plant tRNA expression and post-transcriptional modification. RNA Biol 2021; 18:64-78. [PMID: 32715941 PMCID: PMC7834048 DOI: 10.1080/15476286.2020.1792089] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 06/18/2020] [Accepted: 06/30/2020] [Indexed: 12/27/2022] Open
Abstract
Differences in tRNA expression have been implicated in a remarkable number of biological processes. There is growing evidence that tRNA genes can play dramatically different roles depending on both expression and post-transcriptional modification, yet sequencing tRNAs to measure abundance and detect modifications remains challenging. Their secondary structure and extensive post-transcriptional modifications interfere with RNA-seq library preparation methods and have limited the utility of high-throughput sequencing technologies. Here, we combine two modifications to standard RNA-seq methods by treating with the demethylating enzyme AlkB and ligating with tRNA-specific adapters in order to sequence tRNAs from four species of flowering plants, a group that has been shown to have some of the most extensive rates of post-transcriptional tRNA modifications. This protocol has the advantage of detecting full-length tRNAs and sequence variants that can be used to infer many post-transcriptional modifications. We used the resulting data to produce a modification index of almost all unique reference tRNAs in Arabidopsis thaliana, which exhibited many anciently conserved similarities with humans but also positions that appear to be 'hot spots' for modifications in angiosperm tRNAs. We also found evidence based on northern blot analysis and droplet digital PCR that, even after demethylation treatment, tRNA-seq can produce highly biased estimates of absolute expression levels most likely due to biased reverse transcription. Nevertheless, the generation of full-length tRNA sequences with modification data is still promising for assessing differences in relative tRNA expression across treatments, tissues or subcellular fractions and help elucidate the functional roles of tRNA modifications.
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Affiliation(s)
- Jessica M. Warren
- Department of Biology, Colorado State University, Fort Collins, CO, USA
| | - Thalia Salinas-Giegé
- Institut De Biologie Moléculaire Des plantes-CNRS, Université De Strasbourg, Strasbourg, France
| | - Guillaume Hummel
- Institut De Biologie Moléculaire Des plantes-CNRS, Université De Strasbourg, Strasbourg, France
| | - Nicole L. Coots
- Department of Biology, Colorado State University, Fort Collins, CO, USA
| | | | - Kristen C. Brown
- Department of Biology, Colorado State University, Fort Collins, CO, USA
| | - Laurence Drouard
- Department of Biology, Colorado State University, Fort Collins, CO, USA
- Institut De Biologie Moléculaire Des plantes-CNRS, Université De Strasbourg, Strasbourg, France
| | - Daniel B. Sloan
- Department of Biology, Colorado State University, Fort Collins, CO, USA
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10
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Texada MJ, Koyama T, Rewitz K. Regulation of Body Size and Growth Control. Genetics 2020; 216:269-313. [PMID: 33023929 PMCID: PMC7536854 DOI: 10.1534/genetics.120.303095] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 06/29/2020] [Indexed: 12/20/2022] Open
Abstract
The control of body and organ growth is essential for the development of adults with proper size and proportions, which is important for survival and reproduction. In animals, adult body size is determined by the rate and duration of juvenile growth, which are influenced by the environment. In nutrient-scarce environments in which more time is needed for growth, the juvenile growth period can be extended by delaying maturation, whereas juvenile development is rapidly completed in nutrient-rich conditions. This flexibility requires the integration of environmental cues with developmental signals that govern internal checkpoints to ensure that maturation does not begin until sufficient tissue growth has occurred to reach a proper adult size. The Target of Rapamycin (TOR) pathway is the primary cell-autonomous nutrient sensor, while circulating hormones such as steroids and insulin-like growth factors are the main systemic regulators of growth and maturation in animals. We discuss recent findings in Drosophila melanogaster showing that cell-autonomous environment and growth-sensing mechanisms, involving TOR and other growth-regulatory pathways, that converge on insulin and steroid relay centers are responsible for adjusting systemic growth, and development, in response to external and internal conditions. In addition to this, proper organ growth is also monitored and coordinated with whole-body growth and the timing of maturation through modulation of steroid signaling. This coordination involves interorgan communication mediated by Drosophila insulin-like peptide 8 in response to tissue growth status. Together, these multiple nutritional and developmental cues feed into neuroendocrine hubs controlling insulin and steroid signaling, serving as checkpoints at which developmental progression toward maturation can be delayed. This review focuses on these mechanisms by which external and internal conditions can modulate developmental growth and ensure proper adult body size, and highlights the conserved architecture of this system, which has made Drosophila a prime model for understanding the coordination of growth and maturation in animals.
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Affiliation(s)
| | - Takashi Koyama
- Department of Biology, University of Copenhagen, 2100, Denmark
| | - Kim Rewitz
- Department of Biology, University of Copenhagen, 2100, Denmark
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11
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McCown PJ, Ruszkowska A, Kunkler CN, Breger K, Hulewicz JP, Wang MC, Springer NA, Brown JA. Naturally occurring modified ribonucleosides. WILEY INTERDISCIPLINARY REVIEWS. RNA 2020; 11:e1595. [PMID: 32301288 PMCID: PMC7694415 DOI: 10.1002/wrna.1595] [Citation(s) in RCA: 107] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2020] [Revised: 03/09/2020] [Accepted: 03/11/2020] [Indexed: 12/18/2022]
Abstract
The chemical identity of RNA molecules beyond the four standard ribonucleosides has fascinated scientists since pseudouridine was characterized as the "fifth" ribonucleotide in 1951. Since then, the ever-increasing number and complexity of modified ribonucleosides have been found in viruses and throughout all three domains of life. Such modifications can be as simple as methylations, hydroxylations, or thiolations, complex as ring closures, glycosylations, acylations, or aminoacylations, or unusual as the incorporation of selenium. While initially found in transfer and ribosomal RNAs, modifications also exist in messenger RNAs and noncoding RNAs. Modifications have profound cellular outcomes at various levels, such as altering RNA structure or being essential for cell survival or organism viability. The aberrant presence or absence of RNA modifications can lead to human disease, ranging from cancer to various metabolic and developmental illnesses such as Hoyeraal-Hreidarsson syndrome, Bowen-Conradi syndrome, or Williams-Beuren syndrome. In this review article, we summarize the characterization of all 143 currently known modified ribonucleosides by describing their taxonomic distributions, the enzymes that generate the modifications, and any implications in cellular processes, RNA structure, and disease. We also highlight areas of active research, such as specific RNAs that contain a particular type of modification as well as methodologies used to identify novel RNA modifications. This article is categorized under: RNA Processing > RNA Editing and Modification.
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Affiliation(s)
- Phillip J. McCown
- Department of Chemistry and BiochemistryUniversity of Notre DameNotre DameIndianaUSA
| | - Agnieszka Ruszkowska
- Department of Chemistry and BiochemistryUniversity of Notre DameNotre DameIndianaUSA
- Present address:
Institute of Bioorganic ChemistryPolish Academy of SciencesPoznanPoland
| | - Charlotte N. Kunkler
- Department of Chemistry and BiochemistryUniversity of Notre DameNotre DameIndianaUSA
| | - Kurtis Breger
- Department of Chemistry and BiochemistryUniversity of Notre DameNotre DameIndianaUSA
| | - Jacob P. Hulewicz
- Department of Chemistry and BiochemistryUniversity of Notre DameNotre DameIndianaUSA
| | - Matthew C. Wang
- Department of Chemistry and BiochemistryUniversity of Notre DameNotre DameIndianaUSA
| | - Noah A. Springer
- Department of Chemistry and BiochemistryUniversity of Notre DameNotre DameIndianaUSA
| | - Jessica A. Brown
- Department of Chemistry and BiochemistryUniversity of Notre DameNotre DameIndianaUSA
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12
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Khalique A, Mattijssen S, Haddad AF, Chaudhry S, Maraia RJ. Targeting mitochondrial and cytosolic substrates of TRIT1 isopentenyltransferase: Specificity determinants and tRNA-i6A37 profiles. PLoS Genet 2020; 16:e1008330. [PMID: 32324744 PMCID: PMC7200024 DOI: 10.1371/journal.pgen.1008330] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Revised: 05/05/2020] [Accepted: 03/18/2020] [Indexed: 11/29/2022] Open
Abstract
The tRNA isopentenyltransferases (IPTases), which add an isopentenyl group to N6 of A37 (i6A37) of certain tRNAs, are among a minority of enzymes that modify cytosolic and mitochondrial tRNAs. Pathogenic mutations to the human IPTase, TRIT1, that decrease i6A37 levels, cause mitochondrial insufficiency that leads to neurodevelopmental disease. We show that TRIT1 encodes an amino-terminal mitochondrial targeting sequence (MTS) that directs mitochondrial import and modification of mitochondrial-tRNAs. Full understanding of IPTase function must consider the tRNAs selected for modification, which vary among species, and in their cytosol and mitochondria. Selection is principally via recognition of the tRNA A36-A37-A38 sequence. An exception is unmodified tRNATrpCCA-A37-A38 in Saccharomyces cerevisiae, whereas tRNATrpCCA is readily modified in Schizosaccharomyces pombe, indicating variable IPTase recognition systems and suggesting that additional exceptions may account for some of the tRNA-i6A37 paucity in higher eukaryotes. Yet TRIT1 had not been characterized for restrictive type substrate-specific recognition. We used i6A37-dependent tRNA-mediated suppression and i6A37-sensitive northern blotting to examine IPTase activities in S. pombe and S. cerevisiae lacking endogenous IPTases on a diversity of tRNA-A36-A37-A38 substrates. Point mutations to the TRIT1 MTS that decrease human mitochondrial import, decrease modification of mitochondrial but not cytosolic tRNAs in both yeasts. TRIT1 exhibits clear substrate-specific restriction against a cytosolic-tRNATrpCCA-A37-A38. Additional data suggest that position 32 of tRNATrpCCA is a conditional determinant for substrate-specific i6A37 modification by the restrictive IPTases, Mod5 and TRIT1. The cumulative biochemical and phylogenetic sequence analyses provide new insights into IPTase activities and determinants of tRNA-i6A37 profiles in cytosol and mitochondria.
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Affiliation(s)
- Abdul Khalique
- Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, of the National Institutes of Health, Bethesda, Maryland, United States of America
| | - Sandy Mattijssen
- Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, of the National Institutes of Health, Bethesda, Maryland, United States of America
| | - Alexander F. Haddad
- Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, of the National Institutes of Health, Bethesda, Maryland, United States of America
| | - Shereen Chaudhry
- Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, of the National Institutes of Health, Bethesda, Maryland, United States of America
| | - Richard J. Maraia
- Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, of the National Institutes of Health, Bethesda, Maryland, United States of America
- Commissioned Corps, United States Public Health Service, Rockville, Maryland, United States of America
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13
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Rojas-Benítez D, L. Allende M. Elongator Subunit 3 (Elp3) Is Required for Zebrafish Trunk Development. Int J Mol Sci 2020; 21:E925. [PMID: 32023806 PMCID: PMC7036906 DOI: 10.3390/ijms21030925] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 11/02/2019] [Accepted: 11/06/2019] [Indexed: 12/15/2022] Open
Abstract
Transfer RNAs (tRNAs) are the most post-transcriptionally modified RNA species. Some of these modifications, especially the ones located in the anti-codon loop, are required for decoding capabilities of tRNAs. Such is the case for 5-methoxy-carbonyl-methyl-2-thio-uridine (mcm5s2U), synthetized by the Elongator complex. Mutants for its sub-units display pleiotropic phenotypes. In this paper, we analyze the role of elp3 (Elongator catalytic sub-unit) in zebrafish development. We found that it is required for trunk development; elp3 knock-down animals presented diminished levels of mcm5s2U and sonic hedgehog (Shh) signaling activity. Activation of this pathway was sufficient to revert the phenotype caused by elp3 knockdown, indicating a functional relationship between Elongator and Shh through a yet unknown molecular mechanism.
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Affiliation(s)
- Diego Rojas-Benítez
- FONDAP Center for Genome Regulation (CGR), Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Ñuñoa, Santiago 7800003, Chile;
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14
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Kessi-Pérez EI, Salinas F, González A, Su Y, Guillamón JM, Hall MN, Larrondo LF, Martínez C. KAE1 Allelic Variants Affect TORC1 Activation and Fermentation Kinetics in Saccharomyces cerevisiae. Front Microbiol 2019; 10:1686. [PMID: 31417508 PMCID: PMC6685402 DOI: 10.3389/fmicb.2019.01686] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 07/09/2019] [Indexed: 12/17/2022] Open
Abstract
The eukaryotic domain-conserved TORC1 signalling pathway connects growth with nutrient sufficiency, promoting anabolic processes such as ribosomal biogenesis and protein synthesis. In Saccharomyces cerevisiae, TORC1 is activated mainly by the nitrogen sources. Recently, this pathway has gotten renewed attention but now in the context of the alcoholic fermentation, due to its key role in nitrogen metabolism regulation. Although the distal and proximal effectors downstream TORC1 are well characterised in yeast, the mechanism by which TORC1 is activated by nitrogen sources is not fully understood. In this work, we took advantage of a previously developed microculture-based methodology, which indirectly evaluates TORC1 activation in a nitrogen upshift experiment, to identify genetic variants affecting the activation of this pathway. We used this method to phenotype a recombinant population derived from two strains (SA and WE) with different geographic origins, which show opposite phenotypes for TORC1 activation by glutamine. Using this phenotypic information, we performed a QTL mapping that allowed us to identify several QTLs for TORC1 activation. Using a reciprocal hemizygous analysis, we validated GUS1, KAE1, PIB2, and UTH1 as genes responsible for the natural variation in the TORC1 activation. We observed that reciprocal hemizygous strains for KAE1 (ATPase required for t6A tRNA modification) gene showed the greatest phenotypic differences for TORC1 activation, with the hemizygous strain carrying the SA allele (KAE1SA) showing the higher TORC1 activation. In addition, we evaluated the fermentative capacities of the hemizygous strains under low nitrogen conditions, observing an antagonistic effect for KAE1SA allele, where the hemizygous strain containing this allele presented the lower fermentation rate. Altogether, these results highlight the importance of the tRNA processing in TORC1 activation and connects this pathway with the yeasts fermentation kinetics under nitrogen-limited conditions.
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Affiliation(s)
- Eduardo I Kessi-Pérez
- Departamento de Ciencia y Tecnología de los Alimentos, Universidad de Santiago de Chile (USACH), Santiago, Chile.,Centro de Estudios en Ciencia y Tecnología de Alimentos (CECTA), Universidad de Santiago de Chile (USACH), Santiago, Chile
| | - Francisco Salinas
- Centro de Estudios en Ciencia y Tecnología de Alimentos (CECTA), Universidad de Santiago de Chile (USACH), Santiago, Chile.,Millennium Institute for Integrative Biology (iBio), Santiago, Chile.,Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile (UACH), Valdivia, Chile
| | | | - Ying Su
- Departamento de Biotecnología de los Alimentos, Instituto de Agroquímica y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Valencia, Spain
| | - José M Guillamón
- Departamento de Biotecnología de los Alimentos, Instituto de Agroquímica y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Valencia, Spain
| | | | - Luis F Larrondo
- Millennium Institute for Integrative Biology (iBio), Santiago, Chile.,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Claudio Martínez
- Departamento de Ciencia y Tecnología de los Alimentos, Universidad de Santiago de Chile (USACH), Santiago, Chile.,Centro de Estudios en Ciencia y Tecnología de Alimentos (CECTA), Universidad de Santiago de Chile (USACH), Santiago, Chile
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15
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Hoffmann A, Fallmann J, Vilardo E, Mörl M, Stadler PF, Amman F. Accurate mapping of tRNA reads. Bioinformatics 2019; 34:1116-1124. [PMID: 29228294 DOI: 10.1093/bioinformatics/btx756] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 12/07/2017] [Indexed: 11/12/2022] Open
Abstract
Motivation Many repetitive DNA elements are transcribed at appreciable expression levels. Mapping the corresponding RNA sequencing reads back to a reference genome is notoriously difficult and error-prone task, however. This is in particular true if chemical modifications introduce systematic mismatches, while at the same time the genomic loci are only approximately identical, as in the case of tRNAs. Results We therefore developed a dedicated mapping strategy to handle RNA-seq reads that map to tRNAs relying on a modified target genome in which known tRNA loci are masked and instead intronless tRNA precursor sequences are appended as artificial 'chromosomes'. In a first pass, reads that overlap the boundaries of mature tRNAs are extracted. In the second pass, the remaining reads are mapped to a tRNA-masked target that is augmented by representative mature tRNA sequences. Using both simulated and real life data we show that our best-practice workflow removes most of the mapping artefacts introduced by simpler mapping schemes and makes it possible to reliably identify many of chemical tRNA modifications in generic small RNA-seq data. Using simulated data the FDR is only 2%. We find compelling evidence for tissue specific differences of tRNA modification patterns. Availability and implementation The workflow is available both as a bash script and as a Galaxy workflow from https://github.com/AnneHoffmann/tRNA-read-mapping. Contact fabian@tbi.univie.ac.at. Supplementary information Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Anne Hoffmann
- Bioinformatics Group, Department of Computer Science, and Interdisciplinary Center for Bioinformatics, D-04107 Leipzig, Germany
| | - Jörg Fallmann
- Bioinformatics Group, Department of Computer Science, and Interdisciplinary Center for Bioinformatics, D-04107 Leipzig, Germany
| | - Elisa Vilardo
- Center for Anatomy and Cell Biology, Medical University of Vienna, Austria
| | - Mario Mörl
- Institute for Biochemistry, Leipzig University, D-04103 Leipzig, Germany
| | - Peter F Stadler
- Bioinformatics Group, Department of Computer Science, and Interdisciplinary Center for Bioinformatics, D-04107 Leipzig, Germany.,German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Competence Center for Scalable Data Services and Solutions, and Leipzig Research Center for Civilization Diseases, Leipzig University, D-04107 Leipzig, Germany.,Max Planck Institute for Mathematics in the Sciences, D-04103 Leipzig, Germany.,Fraunhofer Institute for Cell Therapy and Immunology, D-04103 Leipzig, Germany.,Center for RNA in Technology and Health, University of Copenhagen, Frederiksberg C, Denmark.,Santa Fe Institute, Santa Fe, NM 87501, USA.,Department of Theoretical Chemistry of the University of Vienna, A-1090 Vienna, Austria
| | - Fabian Amman
- Department of Theoretical Chemistry of the University of Vienna, A-1090 Vienna, Austria.,Department of Chromosome Biology of the University of Vienna, A-1030 Vienna, Austria
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16
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The emerging impact of tRNA modifications in the brain and nervous system. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2018; 1862:412-428. [PMID: 30529455 DOI: 10.1016/j.bbagrm.2018.11.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 11/21/2018] [Accepted: 11/23/2018] [Indexed: 01/19/2023]
Abstract
A remarkable number of neurodevelopmental disorders have been linked to defects in tRNA modifications. These discoveries place tRNA modifications in the spotlight as critical modulators of gene expression pathways that are required for proper organismal growth and development. Here, we discuss the emerging molecular and cellular functions of the diverse tRNA modifications linked to cognitive and neurological disorders. In particular, we describe how the structure and location of a tRNA modification influences tRNA folding, stability, and function. We then highlight how modifications in tRNA can impact multiple aspects of protein translation that are instrumental for maintaining proper cellular proteostasis. Importantly, we describe how perturbations in tRNA modification lead to a spectrum of deleterious biological outcomes that can disturb neurodevelopment and neurological function. Finally, we summarize the biological themes shared by the different tRNA modifications linked to cognitive disorders and offer insight into the future questions that remain to decipher the role of tRNA modifications. This article is part of a Special Issue entitled: mRNA modifications in gene expression control edited by Dr. Soller Matthias and Dr. Fray Rupert.
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17
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Torrent M, Chalancon G, de Groot NS, Wuster A, Madan Babu M. Cells alter their tRNA abundance to selectively regulate protein synthesis during stress conditions. Sci Signal 2018; 11:11/546/eaat6409. [PMID: 30181241 PMCID: PMC6130803 DOI: 10.1126/scisignal.aat6409] [Citation(s) in RCA: 161] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Decoding the information in mRNA during protein synthesis relies on tRNA adaptors, the abundance of which can affect the decoding rate and translation efficiency. To determine whether cells alter tRNA abundance to selectively regulate protein expression, we quantified changes in the abundance of individual tRNAs at different time points in response to diverse stress conditions in Saccharomyces cerevisiae. We found that the tRNA pool was dynamic and rearranged in a manner that facilitated selective translation of stress-related transcripts. Through genomic analysis of multiple data sets, stochastic simulations, and experiments with designed sequences of proteins with identical amino acids but altered codon usage, we showed that changes in tRNA abundance affected protein expression independently of factors such as mRNA abundance. We suggest that cells alter their tRNA abundance to selectively affect the translation rates of specific transcripts to increase the amounts of required proteins under diverse stress conditions.
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Affiliation(s)
- Marc Torrent
- Laboratory of Molecular Biology, Medical Research Council, Francis Crick Avenue, Cambridge CB2 0QH, UK. .,Systems Biology of Infection Lab, Department of Biochemistry and Molecular Biology, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
| | - Guilhem Chalancon
- Laboratory of Molecular Biology, Medical Research Council, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Natalia S de Groot
- Laboratory of Molecular Biology, Medical Research Council, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Arthur Wuster
- Laboratory of Molecular Biology, Medical Research Council, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - M Madan Babu
- Laboratory of Molecular Biology, Medical Research Council, Francis Crick Avenue, Cambridge CB2 0QH, UK.
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18
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Sriskanthadevan-Pirahas S, Deshpande R, Lee B, Grewal SS. Ras/ERK-signalling promotes tRNA synthesis and growth via the RNA polymerase III repressor Maf1 in Drosophila. PLoS Genet 2018; 14:e1007202. [PMID: 29401457 PMCID: PMC5814106 DOI: 10.1371/journal.pgen.1007202] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 02/15/2018] [Accepted: 01/16/2018] [Indexed: 12/28/2022] Open
Abstract
The small G-protein Ras is a conserved regulator of cell and tissue growth. These effects of Ras are mediated largely through activation of a canonical RAF-MEK-ERK kinase cascade. An important challenge is to identify how this Ras/ERK pathway alters cellular metabolism to drive growth. Here we report on stimulation of RNA polymerase III (Pol III)-mediated tRNA synthesis as a growth effector of Ras/ERK signalling in Drosophila. We find that activation of Ras/ERK signalling promotes tRNA synthesis both in vivo and in cultured Drosophila S2 cells. We also show that Pol III function is required for Ras/ERK signalling to drive proliferation in both epithelial and stem cells in Drosophila tissues. We find that the transcription factor Myc is required but not sufficient for Ras-mediated stimulation of tRNA synthesis. Instead we show that Ras signalling promotes Pol III function and tRNA synthesis by phosphorylating, and inhibiting the nuclear localization and function of the Pol III repressor Maf1. We propose that inhibition of Maf1 and stimulation of tRNA synthesis is one way by which Ras signalling enhances protein synthesis to promote cell and tissue growth.
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Affiliation(s)
- Shrivani Sriskanthadevan-Pirahas
- Clark H Smith Brain Tumour Centre, Arnie Charbonneau Cancer Institute, Alberta Children’s Hospital Research Institute, and Department of Biochemistry and Molecular Biology Calgary, University of Calgary, Calgary, Alberta, Canada
| | - Rujuta Deshpande
- Clark H Smith Brain Tumour Centre, Arnie Charbonneau Cancer Institute, Alberta Children’s Hospital Research Institute, and Department of Biochemistry and Molecular Biology Calgary, University of Calgary, Calgary, Alberta, Canada
| | - Byoungchun Lee
- Clark H Smith Brain Tumour Centre, Arnie Charbonneau Cancer Institute, Alberta Children’s Hospital Research Institute, and Department of Biochemistry and Molecular Biology Calgary, University of Calgary, Calgary, Alberta, Canada
| | - Savraj S. Grewal
- Clark H Smith Brain Tumour Centre, Arnie Charbonneau Cancer Institute, Alberta Children’s Hospital Research Institute, and Department of Biochemistry and Molecular Biology Calgary, University of Calgary, Calgary, Alberta, Canada
- * E-mail:
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19
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Tuorto F, Lyko F. Genome recoding by tRNA modifications. Open Biol 2017; 6:rsob.160287. [PMID: 27974624 PMCID: PMC5204126 DOI: 10.1098/rsob.160287] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 11/14/2016] [Indexed: 11/12/2022] Open
Abstract
RNA modifications are emerging as an additional regulatory layer on top of the primary RNA sequence. These modifications are particularly enriched in tRNAs where they can regulate not only global protein translation, but also protein translation at the codon level. Modifications located in or in the vicinity of tRNA anticodons are highly conserved in eukaryotes and have been identified as potential regulators of mRNA decoding. Recent studies have provided novel insights into how these modifications orchestrate the speed and fidelity of translation to ensure proper protein homeostasis. This review highlights the prominent modifications in the tRNA anticodon loop: queuosine, inosine, 5-methoxycarbonylmethyl-2-thiouridine, wybutosine, threonyl-carbamoyl-adenosine and 5-methylcytosine. We discuss the functional relevance of these modifications in protein translation and their emerging role in eukaryotic genome recoding during cellular adaptation and disease.
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Affiliation(s)
- Francesca Tuorto
- Division of Epigenetics, DKFZ-ZMBH Alliance, German Cancer Research Center, Heidelberg, Germany
| | - Frank Lyko
- Division of Epigenetics, DKFZ-ZMBH Alliance, German Cancer Research Center, Heidelberg, Germany
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20
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Function and Biosynthesis of the Universal tRNA Modification N6-Threonylcarbamoyl-Adenosine. ACTA ACUST UNITED AC 2017. [DOI: 10.1007/978-3-319-65795-0_8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
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21
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Marín M, Fernández-Calero T, Ehrlich R. Protein folding and tRNA biology. Biophys Rev 2017; 9:573-588. [PMID: 28944442 PMCID: PMC5662057 DOI: 10.1007/s12551-017-0322-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 08/28/2017] [Indexed: 12/14/2022] Open
Abstract
Polypeptides can fold into tertiary structures while they are synthesized by the ribosome. In addition to the amino acid sequence, protein folding is determined by several factors within the cell. Among others, the folding pathway of a nascent polypeptide can be affected by transient interactions with other proteins, ligands, or the ribosome, as well as by the translocation through membrane pores. Particularly, the translation machinery and the population of tRNA under different physiological or adaptive responses can dramatically affect protein folding. This review summarizes the scientific evidence describing the role of translation kinetics and tRNA populations on protein folding and addresses current efforts to better understand tRNA biology. It is organized into three main parts, which are focused on: (i) protein folding in the cellular context; (ii) tRNA biology and the complexity of the tRNA population; and (iii) available methods and technical challenges in the characterization of tRNA pools. In this manner, this work illustrates the ways by which functional properties of proteins may be modulated by cellular tRNA populations.
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Affiliation(s)
- Mónica Marín
- Biochemistry-Molecular Biology Section, Cellular and Molecular Biology Department, Faculty of Sciences, Universidad de la República, Iguá 4225, 11400 Montevideo, Uruguay
| | - Tamara Fernández-Calero
- Biochemistry-Molecular Biology Section, Cellular and Molecular Biology Department, Faculty of Sciences, Universidad de la República, Iguá 4225, 11400 Montevideo, Uruguay
- Bioinformatics Unit, Institut Pasteur Montevideo, Mataojo 2020, 11400 Montevideo, Uruguay
| | - Ricardo Ehrlich
- Biochemistry-Molecular Biology Section, Cellular and Molecular Biology Department, Faculty of Sciences, Universidad de la República, Iguá 4225, 11400 Montevideo, Uruguay
- Institut Pasteur Montevideo, Mataojo 2020, 11400 Montevideo, Uruguay
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22
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Bacusmo JM, Orsini SS, Hu J, DeMott M, Thiaville PC, Elfarash A, Paulines MJ, Rojas-Benítez D, Meineke B, Deutsch C, Iwata-Reuyl D, Limbach PA, Dedon PC, Rice KC, Shuman S, Crécy-Lagard VD. The t 6A modification acts as a positive determinant for the anticodon nuclease PrrC, and is distinctively nonessential in Streptococcus mutans. RNA Biol 2017; 15:508-517. [PMID: 28726545 DOI: 10.1080/15476286.2017.1353861] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Endoribonuclease toxins (ribotoxins) are produced by bacteria and fungi to respond to stress, eliminate non-self competitor species, or interdict virus infection. PrrC is a bacterial ribotoxin that targets and cleaves tRNALysUUU in the anticodon loop. In vitro studies suggested that the post-transcriptional modification threonylcarbamoyl adenosine (t6A) is required for PrrC activity but this prediction had never been validated in vivo. Here, by using t6A-deficient yeast derivatives, it is shown that t6A is a positive determinant for PrrC proteins from various bacterial species. Streptococcus mutans is one of the few bacteria where the t6A synthesis gene tsaE (brpB) is dispensable and its genome encodes a PrrC toxin. We had previously shown using an HPLC-based assay that the S. mutans tsaE mutant was devoid of t6A. However, we describe here a novel and a more sensitive hybridization-based t6A detection method (compared to HPLC) that showed t6A was still present in the S. mutans ΔtsaE, albeit at greatly reduced levels (93% reduced compared with WT). Moreover, mutants in 2 other S. mutans t6A synthesis genes (tsaB and tsaC) were shown to be totally devoid of the modification thus confirming its dispensability in this organism. Furthermore, analysis of t6A modification ratios and of t6A synthesis genes mRNA levels in S. mutans suggest they may be regulated by growth phase.
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Affiliation(s)
- Jo Marie Bacusmo
- a Department of Microbiology and Cell Science, IFAS , University of Florida , Gainesville , FL , USA
| | - Silvia S Orsini
- a Department of Microbiology and Cell Science, IFAS , University of Florida , Gainesville , FL , USA
| | - Jennifer Hu
- b Center for Environmental Health Sciences, Department of Biological Engineering , Massachusetts Institute of Technology , Cambridge , MA , USA
| | - Michael DeMott
- b Center for Environmental Health Sciences, Department of Biological Engineering , Massachusetts Institute of Technology , Cambridge , MA , USA
| | - Patrick C Thiaville
- a Department of Microbiology and Cell Science, IFAS , University of Florida , Gainesville , FL , USA.,c Genetics and Genomics Graduate Program , University of Florida , Gainesville , USA.,d University of Florida Genetics Institute, University of Florida , Gainesville , FL , USA
| | - Ameer Elfarash
- a Department of Microbiology and Cell Science, IFAS , University of Florida , Gainesville , FL , USA.,e Genetic Department, Faculty of Agriculture , Assiut University , Assuit , Egypt
| | - Mellie June Paulines
- f Rieveschl Laboratories for Mass Spectrometry, Department of Chemistry , University of Cincinnati , Cincinnati OH , USA
| | - Diego Rojas-Benítez
- g Centro de Regulación del Genoma. Facultad de Ciencias - Universidad de Chile , Santiago , Chile
| | - Birthe Meineke
- h Molecular Biology Program , Sloan-Kettering Institute , New York , NY , USA
| | - Chris Deutsch
- i Department of Chemistry , Portland State University , Portland , OR , USA
| | - Dirk Iwata-Reuyl
- i Department of Chemistry , Portland State University , Portland , OR , USA
| | - Patrick A Limbach
- f Rieveschl Laboratories for Mass Spectrometry, Department of Chemistry , University of Cincinnati , Cincinnati OH , USA
| | - Peter C Dedon
- b Center for Environmental Health Sciences, Department of Biological Engineering , Massachusetts Institute of Technology , Cambridge , MA , USA
| | - Kelly C Rice
- a Department of Microbiology and Cell Science, IFAS , University of Florida , Gainesville , FL , USA
| | - Stewart Shuman
- h Molecular Biology Program , Sloan-Kettering Institute , New York , NY , USA
| | - Valérie de Crécy-Lagard
- a Department of Microbiology and Cell Science, IFAS , University of Florida , Gainesville , FL , USA.,d University of Florida Genetics Institute, University of Florida , Gainesville , FL , USA
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23
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Edvardson S, Prunetti L, Arraf A, Haas D, Bacusmo JM, Hu JF, Ta-Shma A, Dedon PC, de Crécy-Lagard V, Elpeleg O. tRNA N6-adenosine threonylcarbamoyltransferase defect due to KAE1/TCS3 (OSGEP) mutation manifest by neurodegeneration and renal tubulopathy. Eur J Hum Genet 2017; 25:545-551. [PMID: 28272532 DOI: 10.1038/ejhg.2017.30] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 02/01/2017] [Accepted: 02/07/2017] [Indexed: 11/09/2022] Open
Abstract
Post-transcriptional tRNA modifications are numerous and require a large set of highly conserved enzymes in humans and other organisms. In yeast, the loss of many modifications is tolerated under unstressed conditions; one exception is the N6-threonyl-carbamoyl-adenosine (t6A) modification, loss of which causes a severe growth phenotype. Here we aimed at a molecular diagnosis in a brother and sister from a consanguineous family who presented with global developmental delay, failure to thrive and a renal defect manifesting in proteinuria and hypomagnesemia. Using exome sequencing, the patients were found to be homozygous for the c.974G>A (p.(Arg325Gln)) variant of the KAE1 gene. KAE1 is a constituent of the KEOPS complex, a five-subunit complex that catalyzes the second biosynthetic step of t6A in the cytosol. The yeast KAE1 allele carrying the equivalent mutation did not rescue the t6A deficiency of the kae1Δ yeast strain as efficiently as the WT allele; furthermore, t6A levels quantified by LC-MS/MS were lower in the kae1Δ strain which was complemented by the mutation than in the kae1Δ strain, which was complemented by the WT allele. We conclude that homozygosity for c.974G>A (p.(Arg325Gln)) in KAE1 likely exerts its pathogenic effect by perturbing t6A synthesis, thereby interfering with global protein production. This is the first report of t6A biosynthesis defect in human. KAE1 joins the growing list of cytoplasmic tRNA modification enzymes, all associated with severe neurological disorders.
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Affiliation(s)
- Simon Edvardson
- Monique and Jacques Roboh Department of Genetic Research, Hadassah Medical Center, Hebrew University of Jerusalem, Jerusalem, Israel.,Pediatric Neurology Unit, Hadassah Medical Center, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Laurence Prunetti
- Department of Microbiology and Cell Science, Institute for Food and Agricultural Sciences and Genetic Institute, University of Florida, Gainesville, FL, USA
| | - Aiman Arraf
- Hebrew University School of Medicine, Jerusalem, Israel
| | - Drago Haas
- Department of Microbiology and Cell Science, Institute for Food and Agricultural Sciences and Genetic Institute, University of Florida, Gainesville, FL, USA
| | - Jo Marie Bacusmo
- Department of Microbiology and Cell Science, Institute for Food and Agricultural Sciences and Genetic Institute, University of Florida, Gainesville, FL, USA
| | - Jennifer F Hu
- Center for Environmental Health Sciences, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Asas Ta-Shma
- Monique and Jacques Roboh Department of Genetic Research, Hadassah Medical Center, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Peter C Dedon
- Center for Environmental Health Sciences, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.,Infectious Disease Interdisciplinary Research Group, Singapore-MIT Alliance for Research and Technology, Singapore, Singapore
| | - Valérie de Crécy-Lagard
- Department of Microbiology and Cell Science, Institute for Food and Agricultural Sciences and Genetic Institute, University of Florida, Gainesville, FL, USA
| | - Orly Elpeleg
- Monique and Jacques Roboh Department of Genetic Research, Hadassah Medical Center, Hebrew University of Jerusalem, Jerusalem, Israel
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24
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Rojas-Benítez D, Eggers C, Glavic A. Modulation of the Proteostasis Machinery to Overcome Stress Caused by Diminished Levels of t6A-Modified tRNAs in Drosophila. Biomolecules 2017; 7:biom7010025. [PMID: 28272317 PMCID: PMC5372737 DOI: 10.3390/biom7010025] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 02/28/2017] [Indexed: 12/17/2022] Open
Abstract
Transfer RNAs (tRNAs) harbor a subset of post-transcriptional modifications required for structural stability or decoding function. N6-threonylcarbamoyladenosine (t6A) is a universally conserved modification found at position 37 in tRNA that pair A-starting codons (ANN) and is required for proper translation initiation and to prevent frame shift during elongation. In its absence, the synthesis of aberrant proteins is likely, evidenced by the formation of protein aggregates. In this work, our aim was to study the relationship between t6A-modified tRNAs and protein synthesis homeostasis machinery using Drosophila melanogaster. We used the Gal4/UAS system to knockdown genes required for t6A synthesis in a tissue and time specific manner and in vivo reporters of unfolded protein response (UPR) activation. Our results suggest that t6A-modified tRNAs, synthetized by the threonyl-carbamoyl transferase complex (TCTC), are required for organismal growth and imaginal cell survival, and is most likely to support proper protein synthesis.
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Affiliation(s)
- Diego Rojas-Benítez
- Centro de Regulación del Genoma, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Ñuñoa, Santiago 7800024, Chile..
| | - Cristián Eggers
- Centro de Regulación del Genoma, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Ñuñoa, Santiago 7800024, Chile..
| | - Alvaro Glavic
- Centro de Regulación del Genoma, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Ñuñoa, Santiago 7800024, Chile..
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25
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Klassen R, Ciftci A, Funk J, Bruch A, Butter F, Schaffrath R. tRNA anticodon loop modifications ensure protein homeostasis and cell morphogenesis in yeast. Nucleic Acids Res 2016; 44:10946-10959. [PMID: 27496282 PMCID: PMC5159529 DOI: 10.1093/nar/gkw705] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 07/29/2016] [Indexed: 11/17/2022] Open
Abstract
Using budding yeast, we investigated a negative interaction network among genes for tRNA modifications previously implicated in anticodon-codon interaction: 5-methoxy-carbonyl-methyl-2-thio-uridine (mcm5s2U34: ELP3, URM1), pseudouridine (Ψ38/39: DEG1) and cyclic N6-threonyl-carbamoyl-adenosine (ct6A37: TCD1). In line with functional cross talk between these modifications, we find that combined removal of either ct6A37 or Ψ38/39 and mcm5U34 or s2U34 results in morphologically altered cells with synthetic growth defects. Phenotypic suppression by tRNA overexpression suggests that these defects are caused by malfunction of tRNALysUUU or tRNAGlnUUG, respectively. Indeed, mRNA translation and synthesis of the Gln-rich prion Rnq1 are severely impaired in the absence of Ψ38/39 and mcm5U34 or s2U34, and this defect can be rescued by overexpression of tRNAGlnUUG. Surprisingly, we find that combined modification defects in the anticodon loops of different tRNAs induce similar cell polarity- and nuclear segregation defects that are accompanied by increased aggregation of cellular proteins. Since conditional expression of an artificial aggregation-prone protein triggered similar cytological aberrancies, protein aggregation is likely responsible for loss of morphogenesis and cytokinesis control in mutants with inappropriate tRNA anticodon loop modifications.
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Affiliation(s)
- Roland Klassen
- Institut für Biologie, Fachgebiet Mikrobiologie, Universität Kassel, Heinrich-Plett-Str. 40, D-34132 Kassel, Germany
| | - Akif Ciftci
- Institut für Biologie, Fachgebiet Mikrobiologie, Universität Kassel, Heinrich-Plett-Str. 40, D-34132 Kassel, Germany
| | - Johanna Funk
- Institut für Biologie, Fachgebiet Mikrobiologie, Universität Kassel, Heinrich-Plett-Str. 40, D-34132 Kassel, Germany
| | - Alexander Bruch
- Institut für Biologie, Fachgebiet Mikrobiologie, Universität Kassel, Heinrich-Plett-Str. 40, D-34132 Kassel, Germany
| | - Falk Butter
- Institut für Molekulare Biologie, Ackermannweg 4, D-55128 Mainz, Germany
| | - Raffael Schaffrath
- Institut für Biologie, Fachgebiet Mikrobiologie, Universität Kassel, Heinrich-Plett-Str. 40, D-34132 Kassel, Germany
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26
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Thiaville PC, Legendre R, Rojas-Benítez D, Baudin-Baillieu A, Hatin I, Chalancon G, Glavic A, Namy O, de Crécy-Lagard V. Global translational impacts of the loss of the tRNA modification t 6A in yeast. MICROBIAL CELL 2016; 3:29-45. [PMID: 26798630 PMCID: PMC4717488 DOI: 10.15698/mic2016.01.473] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The universal tRNA modification t6A is found at position 37 of nearly
all tRNAs decoding ANN codons. The absence of t6A37 leads
to severe growth defects in baker’s yeast, phenotypes similar to those caused by
defects in mcm5s2U34 synthesis. Mutants in
mcm5s2U34 can be suppressed by
overexpression of tRNALysUUU, but we show t6A
phenotypes could not be suppressed by expressing any individual ANN decoding
tRNA, and t6A and mcm5s2U are not determinants
for each other’s formation. Our results suggest that t6A deficiency,
like mcm5s2U deficiency, leads to protein folding defects,
and show that the absence of t6A led to stress sensitivities (heat,
ethanol, salt) and sensitivity to TOR pathway inhibitors. Additionally,
L-homoserine suppressed the slow growth phenotype seen in
t6A-deficient strains, and proteins aggregates and Advanced Glycation
End-products (AGEs) were increased in the mutants. The global consequences on
translation caused by t6A absence were examined by ribosome
profiling. Interestingly, the absence of t6A did not lead to global
translation defects, but did increase translation initiation at upstream non-AUG
codons and increased frame-shifting in specific genes. Analysis of codon
occupancy rates suggests that one of the major roles of t6A is to
homogenize the process of elongation by slowing the elongation rate at codons
decoded by high abundance tRNAs and I34:C3 pairs while
increasing the elongation rate of rare tRNAs and G34:U3
pairs. This work reveals that the consequences of t6A absence are
complex and multilayered and has set the stage to elucidate the molecular basis
of the observed phenotypes.
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Affiliation(s)
- Patrick C Thiaville
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL 32611, USA; Genetics and Genomics Graduate Program, University of Florida, Gainesville, FL 32610, USA; University of Florida Genetics Institute, University of Florida, Gainesville, FL 32610, USA; Institut de Biologie Intégrative de la Cellule (I2BC), CEA, CNRS, Université Paris-Sud, Bâtiment 400, 91400 Orsay, France
| | - Rachel Legendre
- Institut de Biologie Intégrative de la Cellule (I2BC), CEA, CNRS, Université Paris-Sud, Bâtiment 400, 91400 Orsay, France
| | - Diego Rojas-Benítez
- Centro de Regulación del Genoma. Facultad de Ciencias - Universidad de Chile, Santiago, Chile
| | - Agnès Baudin-Baillieu
- Institut de Biologie Intégrative de la Cellule (I2BC), CEA, CNRS, Université Paris-Sud, Bâtiment 400, 91400 Orsay, France
| | - Isabelle Hatin
- Institut de Biologie Intégrative de la Cellule (I2BC), CEA, CNRS, Université Paris-Sud, Bâtiment 400, 91400 Orsay, France
| | - Guilhem Chalancon
- Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, United Kingdom
| | - Alvaro Glavic
- Centro de Regulación del Genoma. Facultad de Ciencias - Universidad de Chile, Santiago, Chile
| | - Olivier Namy
- Institut de Biologie Intégrative de la Cellule (I2BC), CEA, CNRS, Université Paris-Sud, Bâtiment 400, 91400 Orsay, France
| | - Valérie de Crécy-Lagard
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL 32611, USA; University of Florida Genetics Institute, University of Florida, Gainesville, FL 32610, USA
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27
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Lin CJ, Smibert P, Zhao X, Hu JF, Ramroop J, Kellner SM, Benton MA, Govind S, Dedon PC, Sternglanz R, Lai EC. An extensive allelic series of Drosophila kae1 mutants reveals diverse and tissue-specific requirements for t6A biogenesis. RNA (NEW YORK, N.Y.) 2015; 21:2103-2118. [PMID: 26516084 PMCID: PMC4647464 DOI: 10.1261/rna.053934.115] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 09/14/2015] [Indexed: 06/03/2023]
Abstract
N(6)-threonylcarbamoyl-adenosine (t6A) is one of the few RNA modifications that is universally present in life. This modification occurs at high frequency at position 37 of most tRNAs that decode ANN codons, and stabilizes cognate anticodon-codon interactions. Nearly all genetic studies of the t6A pathway have focused on single-celled organisms. In this study, we report the isolation of an extensive allelic series in the Drosophila ortholog of the core t6A biosynthesis factor Kae1. kae1 hemizygous larvae exhibit decreases in t6A that correlate with allele strength; however, we still detect substantial t6A-modified tRNAs even during the extended larval phase of null alleles. Nevertheless, complementation of Drosophila Kae1 and other t6A factors in corresponding yeast null mutants demonstrates that these metazoan genes execute t6A synthesis. Turning to the biological consequences of t6A loss, we characterize prominent kae1 melanotic masses and show that they are associated with lymph gland overgrowth and ectopic generation of lamellocytes. On the other hand, kae1 mutants exhibit other phenotypes that reflect insufficient tissue growth. Interestingly, whole-tissue and clonal analyses show that strongly mitotic tissues such as imaginal discs are exquisitely sensitive to loss of kae1, whereas nonproliferating tissues are less affected. Indeed, despite overt requirements of t6A for growth of many tissues, certain strong kae1 alleles achieve and sustain enlarged body size during their extended larval phase. Our studies highlight tissue-specific requirements of the t6A pathway in a metazoan context and provide insights into the diverse biological roles of this fundamental RNA modification during animal development and disease.
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Affiliation(s)
- Ching-Jung Lin
- Department of Developmental Biology, Sloan-Kettering Institute, New York, New York 10065, USA
| | - Peter Smibert
- Department of Developmental Biology, Sloan-Kettering Institute, New York, New York 10065, USA Research School of Biological Sciences, The Australian National University, Acton ACT 2601, Australia
| | - Xiaoyu Zhao
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, New York 11794, USA
| | - Jennifer F Hu
- Department of Biological Engineering, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139, USA
| | - Johnny Ramroop
- Department of Biology, The City College of the City University of New York, New York 10031, USA The Graduate Center of the City University of New York, New York 10016, USA
| | - Stefanie M Kellner
- Department of Biological Engineering, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139, USA
| | - Matthew A Benton
- Research School of Biological Sciences, The Australian National University, Acton ACT 2601, Australia
| | - Shubha Govind
- Department of Biology, The City College of the City University of New York, New York 10031, USA The Graduate Center of the City University of New York, New York 10016, USA
| | - Peter C Dedon
- Department of Biological Engineering, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139, USA
| | - Rolf Sternglanz
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, New York 11794, USA
| | - Eric C Lai
- Department of Developmental Biology, Sloan-Kettering Institute, New York, New York 10065, USA
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