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Liu C, Wu X, Gokulnath P, Li G, Xiao J. The Functions and Mechanisms of Translatable Circular RNAs. J Pharmacol Exp Ther 2023; 384:52-60. [PMID: 35609922 DOI: 10.1124/jpet.122.001085] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2021] [Revised: 04/03/2022] [Accepted: 04/29/2022] [Indexed: 12/27/2022] Open
Abstract
Circular RNAs (circRNAs) are covalently closed RNA produced by back-splicing. CircRNAs have been considered as a type of noncoding RNAs for a long time. However, recent studies have shown that circRNAs can be translated into functional proteins. Proteins specifically encoded by circRNAs have been proved to play important roles in cancer pathology. In this review, we introduce the methods commonly used to identify and validate circRNA translation in detail. We also describe the major mechanisms driving the translation of these circRNAs. In addition, we summarize the main functions of the circRNA-encoded proteins in both physiologic and pathologic conditions. Finally, we discuss the therapeutic potential and challenges in the usage of synthetic translatable circRNAs. This brief review highlights recent discoveries made in this field and the progress of therapy based on translatable circRNAs. SIGNIFICANCE STATEMENT: Understanding the translation of circRNA could facilitate the identification of novel drug targets in various diseases. Moreover, some circRNA encoded proteins were demonstrated to have therapeutic functions in cancer. The application of synthetic circRNAs as carriers to achieve stable protein expression in vitro and in vivo has tremendous therapeutic potential.
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Affiliation(s)
- Chang Liu
- Institute of Geriatrics (Shanghai University), Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Medicine, Shanghai University, Nantong, China (C.L., X.W., J.X.); Cardiac Regeneration and Ageing Laboratory, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Life Science, Shanghai University, Shanghai, China (C.L., X.W., J.X.); and Cardiovascular Division of the Massachusetts General Hospitaland Harvard Medical School, Boston, Massachusetts (P.G., G.L.)
| | - Xinying Wu
- Institute of Geriatrics (Shanghai University), Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Medicine, Shanghai University, Nantong, China (C.L., X.W., J.X.); Cardiac Regeneration and Ageing Laboratory, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Life Science, Shanghai University, Shanghai, China (C.L., X.W., J.X.); and Cardiovascular Division of the Massachusetts General Hospitaland Harvard Medical School, Boston, Massachusetts (P.G., G.L.)
| | - Priyanka Gokulnath
- Institute of Geriatrics (Shanghai University), Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Medicine, Shanghai University, Nantong, China (C.L., X.W., J.X.); Cardiac Regeneration and Ageing Laboratory, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Life Science, Shanghai University, Shanghai, China (C.L., X.W., J.X.); and Cardiovascular Division of the Massachusetts General Hospitaland Harvard Medical School, Boston, Massachusetts (P.G., G.L.)
| | - Guoping Li
- Institute of Geriatrics (Shanghai University), Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Medicine, Shanghai University, Nantong, China (C.L., X.W., J.X.); Cardiac Regeneration and Ageing Laboratory, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Life Science, Shanghai University, Shanghai, China (C.L., X.W., J.X.); and Cardiovascular Division of the Massachusetts General Hospitaland Harvard Medical School, Boston, Massachusetts (P.G., G.L.)
| | - Junjie Xiao
- Institute of Geriatrics (Shanghai University), Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Medicine, Shanghai University, Nantong, China (C.L., X.W., J.X.); Cardiac Regeneration and Ageing Laboratory, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Life Science, Shanghai University, Shanghai, China (C.L., X.W., J.X.); and Cardiovascular Division of the Massachusetts General Hospitaland Harvard Medical School, Boston, Massachusetts (P.G., G.L.)
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2
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Baudin-Baillieu A, Namy O. Saccharomyces cerevisiae, a Powerful Model for Studying rRNA Modifications and Their Effects on Translation Fidelity. Int J Mol Sci 2021; 22:ijms22147419. [PMID: 34299038 PMCID: PMC8307265 DOI: 10.3390/ijms22147419] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 07/03/2021] [Accepted: 07/06/2021] [Indexed: 12/31/2022] Open
Abstract
Ribosomal RNA is a major component of the ribosome. This RNA plays a crucial role in ribosome functioning by ensuring the formation of the peptide bond between amino acids and the accurate decoding of the genetic code. The rRNA carries many chemical modifications that participate in its maturation, the formation of the ribosome and its functioning. In this review, we present the different modifications and how they are deposited on the rRNA. We also describe the most recent results showing that the modified positions are not 100% modified, which creates a heterogeneous population of ribosomes. This gave rise to the concept of specialized ribosomes that we discuss. The knowledge accumulated in the yeast Saccharomyces cerevisiae is very helpful to better understand the role of rRNA modifications in humans, especially in ribosomopathies.
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3
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Aliouat A, Hatin I, Bertin P, François P, Stierlé V, Namy O, Salhi S, Jean-Jean O. Divergent effects of translation termination factor eRF3A and nonsense-mediated mRNA decay factor UPF1 on the expression of uORF carrying mRNAs and ribosome protein genes. RNA Biol 2019; 17:227-239. [PMID: 31619139 PMCID: PMC6973328 DOI: 10.1080/15476286.2019.1674595] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
In addition to its role in translation termination, eRF3A has been implicated in the nonsense-mediated mRNA decay (NMD) pathway through its interaction with UPF1. NMD is a RNA quality control mechanism, which detects and degrades aberrant mRNAs as well as some normal transcripts including those that harbour upstream open reading frames in their 5ʹ leader sequence. In this study, we used RNA-sequencing and ribosome profiling to perform a genome wide analysis of the effect of either eRF3A or UPF1 depletion in human cells. Our bioinformatics analyses allow to delineate the features of the transcripts controlled by eRF3A and UPF1 and to compare the effect of each of these factors on gene expression. We find that eRF3A and UPF1 have very different impacts on the human transcriptome, less than 250 transcripts being targeted by both factors. We show that eRF3A depletion globally derepresses the expression of mRNAs containing translated uORFs while UPF1 knockdown derepresses only the mRNAs harbouring uORFs with an AUG codon in an optimal context for translation initiation. Finally, we also find that eRF3A and UPF1 have opposite effects on ribosome protein gene expression. Together, our results provide important elements for understanding the impact of translation termination and NMD on the human transcriptome and reveal novel determinants of ribosome biogenesis regulation.
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Affiliation(s)
- Affaf Aliouat
- Sorbonne Université, CNRS, Biological Adaptation and Aging, B2A, 75005 Paris, France
| | - Isabelle Hatin
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ Paris Sud, Université Paris-Saclay, Gif sur Yvette cedex, France
| | - Pierre Bertin
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ Paris Sud, Université Paris-Saclay, Gif sur Yvette cedex, France
| | - Pauline François
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ Paris Sud, Université Paris-Saclay, Gif sur Yvette cedex, France
| | - Vérène Stierlé
- Sorbonne Université, CNRS, Biological Adaptation and Aging, B2A, 75005 Paris, France
| | - Olivier Namy
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ Paris Sud, Université Paris-Saclay, Gif sur Yvette cedex, France
| | - Samia Salhi
- Sorbonne Université, CNRS, Biological Adaptation and Aging, B2A, 75005 Paris, France
| | - Olivier Jean-Jean
- Sorbonne Université, CNRS, Biological Adaptation and Aging, B2A, 75005 Paris, France
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4
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Michel AM, Kiniry SJ, O'Connor PBF, Mullan JP, Baranov PV. GWIPS-viz: 2018 update. Nucleic Acids Res 2019; 46:D823-D830. [PMID: 28977460 PMCID: PMC5753223 DOI: 10.1093/nar/gkx790] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Accepted: 08/29/2017] [Indexed: 12/15/2022] Open
Abstract
The GWIPS-viz browser (http://gwips.ucc.ie/) is an on-line genome browser which is tailored for exploring ribosome profiling (Ribo-seq) data. Since its publication in 2014, GWIPS-viz provides Ribo-seq data for an additional 14 genomes bringing the current total to 23. The integration of new Ribo-seq data has been automated thereby increasing the number of available tracks to 1792, a 10-fold increase in the last three years. The increase is particularly substantial for data derived from human sources. Following user requests, we added the functionality to download these tracks in bigWig format. We also incorporated new types of data (e.g. TCP-seq) as well as auxiliary tracks from other sources that help with the interpretation of Ribo-seq data. Improvements in the visualization of the data have been carried out particularly for bacterial genomes where the Ribo-seq data are now shown in a strand specific manner. For higher eukaryotic datasets, we provide characteristics of individual datasets using the RUST program which includes the triplet periodicity, sequencing biases and relative inferred A-site dwell times. This information can be used for assessing the quality of Ribo-seq datasets. To improve the power of the signal, we aggregate Ribo-seq data from several studies into Global aggregate tracks for each genome.
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Affiliation(s)
- Audrey M Michel
- School of Biochemistry and Cell Biology, University College Cork, Cork, Ireland
| | - Stephen J Kiniry
- School of Biochemistry and Cell Biology, University College Cork, Cork, Ireland
| | | | - James P Mullan
- School of Biochemistry and Cell Biology, University College Cork, Cork, Ireland
| | - Pavel V Baranov
- School of Biochemistry and Cell Biology, University College Cork, Cork, Ireland
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Planchard N, Bertin P, Quadrado M, Dargel-Graffin C, Hatin I, Namy O, Mireau H. The translational landscape of Arabidopsis mitochondria. Nucleic Acids Res 2019; 46:6218-6228. [PMID: 29873797 PMCID: PMC6159524 DOI: 10.1093/nar/gky489] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 05/22/2018] [Indexed: 11/14/2022] Open
Abstract
Messenger RNA translation is a complex process that is still poorly understood in eukaryotic organelles like mitochondria. Growing evidence indicates though that mitochondrial translation differs from its bacterial counterpart in many key aspects. In this analysis, we have used ribosome profiling technology to generate a genome-wide snapshot view of mitochondrial translation in Arabidopsis. We show that, unlike in humans, most Arabidopsis mitochondrial ribosome footprints measure 27 and 28 bases. We also reveal that respiratory subunits encoding mRNAs show much higher ribosome association than other mitochondrial mRNAs, implying that they are translated at higher levels. Homogenous ribosome densities were generally detected within each respiratory complex except for complex V, where higher ribosome coverage corroborated with higher requirements for specific subunits. In complex I respiratory mutants, a reorganization of mitochondrial mRNAs ribosome association was detected involving increased ribosome densities for certain ribosomal protein encoding transcripts and a reduction in translation of a few complex V mRNAs. Taken together, our observations reveal that plant mitochondrial translation is a dynamic process and that translational control is important for gene expression in plant mitochondria. This study paves the way for future advances in the understanding translation in higher plant mitochondria.
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Affiliation(s)
- Noelya Planchard
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, RD10, 78026 Versailles Cedex, France.,Paris-Sud University, Université Paris-Saclay, 91405 Orsay Cedex, France
| | - Pierre Bertin
- Institute for Integrative Biology of the Cell (I2BC), UMR 9198 CEA, CNRS, Univ. Paris Sud, Bâtiment 400, 91405 Orsay, France
| | - Martine Quadrado
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, RD10, 78026 Versailles Cedex, France
| | - Céline Dargel-Graffin
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, RD10, 78026 Versailles Cedex, France
| | - Isabelle Hatin
- Institute for Integrative Biology of the Cell (I2BC), UMR 9198 CEA, CNRS, Univ. Paris Sud, Bâtiment 400, 91405 Orsay, France
| | - Olivier Namy
- Institute for Integrative Biology of the Cell (I2BC), UMR 9198 CEA, CNRS, Univ. Paris Sud, Bâtiment 400, 91405 Orsay, France
| | - Hakim Mireau
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, RD10, 78026 Versailles Cedex, France
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6
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Durand É, Gagnon-Arsenault I, Hallin J, Hatin I, Dubé AK, Nielly-Thibault L, Namy O, Landry CR. Turnover of ribosome-associated transcripts from de novo ORFs produces gene-like characteristics available for de novo gene emergence in wild yeast populations. Genome Res 2019; 29:932-943. [PMID: 31152050 PMCID: PMC6581059 DOI: 10.1101/gr.239822.118] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Accepted: 05/13/2019] [Indexed: 12/17/2022]
Abstract
Little is known about the rate of emergence of de novo genes, what their initial properties are, and how they spread in populations. We examined wild yeast populations (Saccharomyces paradoxus) to characterize the diversity and turnover of intergenic ORFs over short evolutionary timescales. We find that hundreds of intergenic ORFs show translation signatures similar to canonical genes, and we experimentally confirmed the translation of many of these ORFs in laboratory conditions using a reporter assay. Compared with canonical genes, intergenic ORFs have lower translation efficiency, which could imply a lack of optimization for translation or a mechanism to reduce their production cost. Translated intergenic ORFs also tend to have sequence properties that are generally close to those of random intergenic sequences. However, some of the very recent translated intergenic ORFs, which appeared <110 kya, already show gene-like characteristics, suggesting that the raw material for functional innovations could appear over short evolutionary timescales.
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Affiliation(s)
- Éléonore Durand
- Institut de Biologie Intégrative et des Systèmes, Département de Biologie, PROTEO, Centre de Recherche en Données Massives de l'Université Laval, Pavillon Charles-Eugène-Marchand, Université Laval, G1V 0A6 Québec, Québec, Canada
| | - Isabelle Gagnon-Arsenault
- Institut de Biologie Intégrative et des Systèmes, Département de Biologie, PROTEO, Centre de Recherche en Données Massives de l'Université Laval, Pavillon Charles-Eugène-Marchand, Université Laval, G1V 0A6 Québec, Québec, Canada.,Département de Biochimie, Microbiologie et Bio-informatique, Université Laval, G1V 0A6 Québec, Québec, Canada
| | - Johan Hallin
- Institut de Biologie Intégrative et des Systèmes, Département de Biologie, PROTEO, Centre de Recherche en Données Massives de l'Université Laval, Pavillon Charles-Eugène-Marchand, Université Laval, G1V 0A6 Québec, Québec, Canada.,Département de Biochimie, Microbiologie et Bio-informatique, Université Laval, G1V 0A6 Québec, Québec, Canada
| | - Isabelle Hatin
- Institut de Biologie Intégrative de la Cellule (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91190 Gif sur Yvette, France
| | - Alexandre K Dubé
- Institut de Biologie Intégrative et des Systèmes, Département de Biologie, PROTEO, Centre de Recherche en Données Massives de l'Université Laval, Pavillon Charles-Eugène-Marchand, Université Laval, G1V 0A6 Québec, Québec, Canada.,Département de Biochimie, Microbiologie et Bio-informatique, Université Laval, G1V 0A6 Québec, Québec, Canada
| | - Lou Nielly-Thibault
- Institut de Biologie Intégrative et des Systèmes, Département de Biologie, PROTEO, Centre de Recherche en Données Massives de l'Université Laval, Pavillon Charles-Eugène-Marchand, Université Laval, G1V 0A6 Québec, Québec, Canada
| | - Olivier Namy
- Institut de Biologie Intégrative de la Cellule (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91190 Gif sur Yvette, France
| | - Christian R Landry
- Institut de Biologie Intégrative et des Systèmes, Département de Biologie, PROTEO, Centre de Recherche en Données Massives de l'Université Laval, Pavillon Charles-Eugène-Marchand, Université Laval, G1V 0A6 Québec, Québec, Canada.,Département de Biochimie, Microbiologie et Bio-informatique, Université Laval, G1V 0A6 Québec, Québec, Canada
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7
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Zhao J, Qin B, Nikolay R, Spahn CMT, Zhang G. Translatomics: The Global View of Translation. Int J Mol Sci 2019; 20:ijms20010212. [PMID: 30626072 PMCID: PMC6337585 DOI: 10.3390/ijms20010212] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 12/19/2018] [Accepted: 01/02/2019] [Indexed: 01/01/2023] Open
Abstract
In all kingdoms of life, proteins are synthesized by ribosomes in a process referred to as translation. The amplitude of translational regulation exceeds the sum of transcription, mRNA degradation and protein degradation. Therefore, it is essential to investigate translation in a global scale. Like the other “omics”-methods, translatomics investigates the totality of the components in the translation process, including but not limited to translating mRNAs, ribosomes, tRNAs, regulatory RNAs and nascent polypeptide chains. Technical advances in recent years have brought breakthroughs in the investigation of these components at global scale, both for their composition and dynamics. These methods have been applied in a rapidly increasing number of studies to reveal multifaceted aspects of translation control. The process of translation is not restricted to the conversion of mRNA coding sequences into polypeptide chains, it also controls the composition of the proteome in a delicate and responsive way. Therefore, translatomics has extended its unique and innovative power to many fields including proteomics, cancer research, bacterial stress response, biological rhythmicity and plant biology. Rational design in translation can enhance recombinant protein production for thousands of times. This brief review summarizes the main state-of-the-art methods of translatomics, highlights recent discoveries made in this field and introduces applications of translatomics on basic biological and biomedical research.
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Affiliation(s)
- Jing Zhao
- Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Institute of Life and Health Engineering, College of Life Science and Technology, Jinan University, Guangzhou 510632, China.
| | - Bo Qin
- Institut für Medizinische Physik und Biophysik, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany.
| | - Rainer Nikolay
- Institut für Medizinische Physik und Biophysik, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany.
| | - Christian M T Spahn
- Institut für Medizinische Physik und Biophysik, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany.
| | - Gong Zhang
- Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Institute of Life and Health Engineering, College of Life Science and Technology, Jinan University, Guangzhou 510632, China.
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Affiliation(s)
- Stephen J. Kiniry
- School of Biochemistry and Cell Biology, University College Cork; Cork Ireland
| | - Audrey M. Michel
- School of Biochemistry and Cell Biology, University College Cork; Cork Ireland
| | - Pavel V. Baranov
- School of Biochemistry and Cell Biology, University College Cork; Cork Ireland
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Li YF, Mahalingam R, Sunkar R. Isolation of Polysomal RNA for Analyzing Stress-Responsive Genes Regulated at the Translational Level in Plants. Methods Mol Biol 2017; 1631:151-161. [PMID: 28735396 DOI: 10.1007/978-1-4939-7136-7_9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Alteration of gene expression is an essential mechanism, which allows plants to respond and adapt to adverse environmental conditions. Transcriptome and proteome analyses in plants exposed to abiotic stresses revealed that protein levels are not correlated with the changes in corresponding mRNAs, indicating regulation at translational level is another major regulator for gene expression. Analysis of translatome, which refers to all mRNAs associated with ribosomes, thus has the potential to bridge the gap between transcriptome and proteome. Polysomal RNA profiling and recently developed ribosome profiling (Ribo-seq) are two main methods for translatome analysis at global level. Here, we describe the classical procedure for polysomal RNA isolation by sucrose gradient ultracentrifugation followed by highthroughput RNA-seq to identify genes regulated at translational level. Polysomal RNA can be further used for a variety of downstream applications including Northern blot analysis, qRT-PCR, RNase protection assay, and microarray-based gene expression profiling.
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Affiliation(s)
- Yong-Fang Li
- College of Life Sciences, Henan Normal University, Xinxiang, 453007, Henan, China
| | | | - Ramanjulu Sunkar
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK, 74078, USA.
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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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