1
|
Stewart RK, Nguyen P, Laederach A, Volkan PC, Sawyer JK, Fox DT. Orb2 enables rare-codon-enriched mRNA expression during Drosophila neuron differentiation. Nat Commun 2024; 15:5270. [PMID: 38902233 PMCID: PMC11190236 DOI: 10.1038/s41467-024-48344-8] [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: 08/10/2023] [Accepted: 04/25/2024] [Indexed: 06/22/2024] Open
Abstract
Regulation of codon optimality is an increasingly appreciated layer of cell- and tissue-specific protein expression control. Here, we use codon-modified reporters to show that differentiation of Drosophila neural stem cells into neurons enables protein expression from rare-codon-enriched genes. From a candidate screen, we identify the cytoplasmic polyadenylation element binding (CPEB) protein Orb2 as a positive regulator of rare-codon-dependent mRNA stability in neurons. Using RNA sequencing, we reveal that Orb2-upregulated mRNAs in the brain with abundant Orb2 binding sites have a rare-codon bias. From these Orb2-regulated mRNAs, we demonstrate that rare-codon enrichment is important for mRNA stability and social behavior function of the metabotropic glutamate receptor (mGluR). Our findings reveal a molecular mechanism by which neural stem cell differentiation shifts genetic code regulation to enable critical mRNA stability and protein expression.
Collapse
Affiliation(s)
- Rebeccah K Stewart
- Department of Pharmacology & Cancer Biology, Duke University, Durham, NC, USA
- Duke Regeneration Center, Duke University, Durham, NC, USA
| | - Patrick Nguyen
- Department of Pharmacology & Cancer Biology, Duke University, Durham, NC, USA
| | - Alain Laederach
- Department of Biology, University of North Carolina, Chapel Hill, NC, USA
| | | | - Jessica K Sawyer
- Department of Pharmacology & Cancer Biology, Duke University, Durham, NC, USA
- Duke Regeneration Center, Duke University, Durham, NC, USA
| | - Donald T Fox
- Department of Pharmacology & Cancer Biology, Duke University, Durham, NC, USA.
- Duke Regeneration Center, Duke University, Durham, NC, USA.
| |
Collapse
|
2
|
Ward C, Beharry A, Tennakoon R, Rozik P, Wilhelm SDP, Heinemann IU, O'Donoghue P. Mechanisms and Delivery of tRNA Therapeutics. Chem Rev 2024. [PMID: 38801719 DOI: 10.1021/acs.chemrev.4c00142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Transfer ribonucleic acid (tRNA) therapeutics will provide personalized and mutation specific medicines to treat human genetic diseases for which no cures currently exist. The tRNAs are a family of adaptor molecules that interpret the nucleic acid sequences in our genes into the amino acid sequences of proteins that dictate cell function. Humans encode more than 600 tRNA genes. Interestingly, even healthy individuals contain some mutant tRNAs that make mistakes. Missense suppressor tRNAs insert the wrong amino acid in proteins, and nonsense suppressor tRNAs read through premature stop signals to generate full length proteins. Mutations that underlie many human diseases, including neurodegenerative diseases, cancers, and diverse rare genetic disorders, result from missense or nonsense mutations. Thus, specific tRNA variants can be strategically deployed as therapeutic agents to correct genetic defects. We review the mechanisms of tRNA therapeutic activity, the nature of the therapeutic window for nonsense and missense suppression as well as wild-type tRNA supplementation. We discuss the challenges and promises of delivering tRNAs as synthetic RNAs or as gene therapies. Together, tRNA medicines will provide novel treatments for common and rare genetic diseases in humans.
Collapse
|
3
|
Scheepbouwer C, Aparicio-Puerta E, Gómez-Martin C, van Eijndhoven MA, Drees EE, Bosch L, de Jong D, Wurdinger T, Zijlstra JM, Hackenberg M, Gerber A, Pegtel DM. Full-length tRNAs lacking a functional CCA tail are selectively sorted into the lumen of extracellular vesicles. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.12.593148. [PMID: 38765958 PMCID: PMC11100784 DOI: 10.1101/2024.05.12.593148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Small extracellular vesicles (sEVs) are heterogenous lipid membrane particles typically less than 200 nm in size and secreted by most cell types either constitutively or upon activation signals. sEVs isolated from biofluids contain RNAs, including small non-coding RNAs (ncRNAs), that can be either encapsulated within the EV lumen or bound to the EV surface. EV-associated microRNAs (miRNAs) are, despite a relatively low abundance, extensively investigated for their selective incorporation and their role in cell-cell communication. In contrast, the sorting of highly-structured ncRNA species is understudied, mainly due to technical limitations of traditional small RNA sequencing protocols. Here, we adapted ALL-tRNAseq to profile the relative abundance of highly structured and potentially methylated small ncRNA species, including transfer RNAs (tRNAs), small nucleolar RNAs (snoRNAs), and Y RNAs in bulk EV preparations. We determined that full-length tRNAs, typically 75 to 90 nucleotides in length, were the dominant small ncRNA species (>60% of all reads in the 18-120 nucleotides size-range) in all cell culture-derived EVs, as well as in human plasma-derived EV samples, vastly outnumbering 21 nucleotides-long miRNAs. Nearly all EV-associated tRNAs were protected from external RNAse treatment, indicating a location within the EV lumen. Strikingly, the vast majority of luminal-sorted, full-length, nucleobase modification-containing EV-tRNA sequences, harbored a dysfunctional 3' CCA tail, 1 to 3 nucleotides truncated, rendering them incompetent for amino acid loading. In contrast, in non-EV associated extracellular particle fractions (NVEPs), tRNAs appeared almost exclusively fragmented or 'nicked' into tRNA-derived small RNAs (tsRNAs) with lengths between 18 to 35 nucleotides. We propose that in mammalian cells, tRNAs that lack a functional 3' CCA tail are selectively sorted into EVs and shuttled out of the producing cell, offering a new perspective into the physiological role of secreted EVs and luminal cargo-selection.
Collapse
Affiliation(s)
- Chantal Scheepbouwer
- Department of Neurosurgery, Cancer Center Amsterdam, Amsterdam University Medical Center, VU University, Amsterdam, Netherlands
- Cancer Center Amsterdam, Cancer Biology, Amsterdam, Netherlands
- Department of Pathology, Cancer Center Amsterdam, Amsterdam University Medical Center, VU University, Amsterdam, Netherlands
| | - Ernesto Aparicio-Puerta
- Department of Biostatistics and Computational Biology, University of Rochester Medical Center, Rochester, NY, USA
| | - Cristina Gómez-Martin
- Department of Pathology, Cancer Center Amsterdam, Amsterdam University Medical Center, VU University, Amsterdam, Netherlands
- Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, Netherlands
| | - Monique A.J. van Eijndhoven
- Department of Pathology, Cancer Center Amsterdam, Amsterdam University Medical Center, VU University, Amsterdam, Netherlands
- Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, Netherlands
| | - Esther E.E. Drees
- Department of Pathology, Cancer Center Amsterdam, Amsterdam University Medical Center, VU University, Amsterdam, Netherlands
- Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, Netherlands
- Department of Hematology, Cancer Center Amsterdam, Amsterdam University Medical Center, VU University, Amsterdam, Netherlands
| | - Leontien Bosch
- Department of Pathology, Cancer Center Amsterdam, Amsterdam University Medical Center, VU University, Amsterdam, Netherlands
- Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, Netherlands
| | - Daphne de Jong
- Department of Pathology, Cancer Center Amsterdam, Amsterdam University Medical Center, VU University, Amsterdam, Netherlands
- Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, Netherlands
| | - Thomas Wurdinger
- Department of Neurosurgery, Cancer Center Amsterdam, Amsterdam University Medical Center, VU University, Amsterdam, Netherlands
- Cancer Center Amsterdam, Cancer Biology, Amsterdam, Netherlands
- Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, Netherlands
| | - Josée M. Zijlstra
- Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, Netherlands
- Department of Hematology, Cancer Center Amsterdam, Amsterdam University Medical Center, VU University, Amsterdam, Netherlands
| | - Michael Hackenberg
- Bioinformatics Laboratory, Biomedical Research Centre (CIBM), Biotechnology Institute, PTS, Avda. del Conocimiento s/n, 18100 Granada, Spain
- Genetics Department, Faculty of Science, Universidad de Granada, Campus de Fuentenueva s/n, 18071 Granada, Spain
- Excellence Research Unit “Modeling Nature” (MNat), University of Granada, Spain
- Instituto de Investigación Biosanitaria ibs. Granada, University Hospitals of Granada-University of Granada, Spain; Conocimiento s/n 18100, Granada. Spain
| | - Alan Gerber
- Department of Neurosurgery, Cancer Center Amsterdam, Amsterdam University Medical Center, VU University, Amsterdam, Netherlands
- Cancer Center Amsterdam, Cancer Biology, Amsterdam, Netherlands
| | - D. Michiel Pegtel
- Department of Pathology, Cancer Center Amsterdam, Amsterdam University Medical Center, VU University, Amsterdam, Netherlands
- Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, Netherlands
| |
Collapse
|
4
|
Kapur M, Molumby MJ, Guzman C, Heinz S, Ackerman SL. Cell-type-specific expression of tRNAs in the brain regulates cellular homeostasis. Neuron 2024; 112:1397-1415.e6. [PMID: 38377989 PMCID: PMC11065635 DOI: 10.1016/j.neuron.2024.01.028] [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: 07/25/2023] [Revised: 12/23/2023] [Accepted: 01/29/2024] [Indexed: 02/22/2024]
Abstract
Defects in tRNA biogenesis are associated with multiple neurological disorders, yet our understanding of these diseases has been hampered by an inability to determine tRNA expression in individual cell types within a complex tissue. Here, we developed a mouse model in which RNA polymerase III is conditionally epitope tagged in a Cre-dependent manner, allowing us to accurately profile tRNA expression in any cell type in vivo. We investigated tRNA expression in diverse nervous system cell types, revealing dramatic heterogeneity in the expression of tRNA genes between populations. We found that while maintenance of levels of tRNA isoacceptor families is critical for cellular homeostasis, neurons are differentially vulnerable to insults to distinct tRNA isoacceptor families. Cell-type-specific translatome analysis suggests that the balance between tRNA availability and codon demand may underlie such differential resilience. Our work provides a platform for investigating the complexities of mRNA translation and tRNA biology in the brain.
Collapse
Affiliation(s)
- Mridu Kapur
- Department of Cellular and Molecular Medicine, University of California, San Diego, School of Medicine, La Jolla, CA 92093, USA; The Howard Hughes Medical Institute
| | - Michael J Molumby
- Department of Cellular and Molecular Medicine, University of California, San Diego, School of Medicine, La Jolla, CA 92093, USA; The Howard Hughes Medical Institute
| | - Carlos Guzman
- Department of Medicine, Division of Endocrinology, School of Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Department of Bioengineering, Bioinformatics & Systems Biology Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA
| | - Sven Heinz
- Department of Medicine, Division of Endocrinology, School of Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Department of Bioengineering, Bioinformatics & Systems Biology Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA
| | - Susan L Ackerman
- Department of Cellular and Molecular Medicine, University of California, San Diego, School of Medicine, La Jolla, CA 92093, USA; The Howard Hughes Medical Institute; Department of Neurobiology, Division of Biological Sciences, University of California, San Diego, La Jolla, CA 92093, USA.
| |
Collapse
|
5
|
Bharti N, Santos L, Davyt M, Behrmann S, Eichholtz M, Jimenez-Sanchez A, Hong JS, Rab A, Sorscher EJ, Albers S, Ignatova Z. Translation velocity determines the efficacy of engineered suppressor tRNAs on pathogenic nonsense mutations. Nat Commun 2024; 15:2957. [PMID: 38580646 PMCID: PMC10997658 DOI: 10.1038/s41467-024-47258-9] [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: 09/20/2023] [Accepted: 03/20/2024] [Indexed: 04/07/2024] Open
Abstract
Nonsense mutations - the underlying cause of approximately 11% of all genetic diseases - prematurely terminate protein synthesis by mutating a sense codon to a premature stop or termination codon (PTC). An emerging therapeutic strategy to suppress nonsense defects is to engineer sense-codon decoding tRNAs to readthrough and restore translation at PTCs. However, the readthrough efficiency of the engineered suppressor tRNAs (sup-tRNAs) largely varies in a tissue- and sequence context-dependent manner and has not yet yielded optimal clinical efficacy for many nonsense mutations. Here, we systematically analyze the suppression efficacy at various pathogenic nonsense mutations. We discover that the translation velocity of the sequence upstream of PTCs modulates the sup-tRNA readthrough efficacy. The PTCs most refractory to suppression are embedded in a sequence context translated with an abrupt reversal of the translation speed leading to ribosomal collisions. Moreover, modeling translation velocity using Ribo-seq data can accurately predict the suppression efficacy at PTCs. These results reveal previously unknown molecular signatures contributing to genotype-phenotype relationships and treatment-response heterogeneity, and provide the framework for the development of personalized tRNA-based gene therapies.
Collapse
Affiliation(s)
- Nikhil Bharti
- Institute of Biochemistry and Molecular Biology, University of Hamburg, 20146, Hamburg, Germany
| | - Leonardo Santos
- Institute of Biochemistry and Molecular Biology, University of Hamburg, 20146, Hamburg, Germany
| | - Marcos Davyt
- Institute of Biochemistry and Molecular Biology, University of Hamburg, 20146, Hamburg, Germany
| | - Stine Behrmann
- Institute of Biochemistry and Molecular Biology, University of Hamburg, 20146, Hamburg, Germany
| | - Marie Eichholtz
- Institute of Biochemistry and Molecular Biology, University of Hamburg, 20146, Hamburg, Germany
| | | | - Jeong S Hong
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA, 30322, USA
- Children's Healthcare of Atlanta, Atlanta, GA, 30322, USA
| | - Andras Rab
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA, 30322, USA
- Children's Healthcare of Atlanta, Atlanta, GA, 30322, USA
| | - Eric J Sorscher
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA, 30322, USA
- Children's Healthcare of Atlanta, Atlanta, GA, 30322, USA
| | - Suki Albers
- Institute of Biochemistry and Molecular Biology, University of Hamburg, 20146, Hamburg, Germany.
| | - Zoya Ignatova
- Institute of Biochemistry and Molecular Biology, University of Hamburg, 20146, Hamburg, Germany.
| |
Collapse
|
6
|
Nakano Y, Gamper H, McGuigan H, Maharjan S, Sun Z, Krishnan K, Yigit E, Li NS, Piccirilli JA, Kleiner R, Nichols N, Hou YM. Genome-Wide Profiling of tRNA Using an Unexplored Reverse Transcriptase with High Processivity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.09.569604. [PMID: 38106225 PMCID: PMC10723452 DOI: 10.1101/2023.12.09.569604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Monitoring the dynamic changes of cellular tRNA pools is challenging, due to the extensive post-transcriptional modifications of individual species. The most critical component in tRNAseq is a processive reverse transcriptase (RT) that can read through each modification with high efficiency. Here we show that the recently developed group-II intron RT Induro has the processivity and efficiency necessary to profile tRNA dynamics. Using our Induro-tRNAseq, simpler and more comprehensive than the best methods to date, we show that Induro progressively increases readthrough of tRNA over time and that the mechanism of increase is selective removal of RT stops, without altering the misincorporation frequency. We provide a parallel dataset of the misincorporation profile of Induro relative to the related TGIRT RT to facilitate the prediction of non-annotated modifications. We report an unexpected modification profile among human proline isoacceptors, absent from mouse and lower eukaryotes, that indicates new biology of decoding proline codons.
Collapse
|
7
|
Akins RB, Ostberg K, Cherlin T, Tsiouplis NJ, Loher P, Rigoutsos I. The Typical tRNA Co-Expresses Multiple 5' tRNA Halves Whose Sequences and Abundances Depend on Isodecoder and Isoacceptor and Change with Tissue Type, Cell Type, and Disease. Noncoding RNA 2023; 9:69. [PMID: 37987365 PMCID: PMC10660753 DOI: 10.3390/ncrna9060069] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 10/02/2023] [Accepted: 10/12/2023] [Indexed: 11/22/2023] Open
Abstract
Transfer RNA-derived fragments (tRFs) are noncoding RNAs that arise from either mature transfer RNAs (tRNAs) or their precursors. One important category of tRFs comprises the tRNA halves, which are generated through cleavage at the anticodon. A given tRNA typically gives rise to several co-expressed 5'-tRNA halves (5'-tRHs) that differ in the location of their 3' ends. These 5'-tRHs, even though distinct, have traditionally been treated as indistinguishable from one another due to their near-identical sequences and lengths. We focused on co-expressed 5'-tRHs that arise from the same tRNA and systematically examined their exact sequences and abundances across 10 different human tissues. To this end, we manually curated and analyzed several hundred human RNA-seq datasets from NCBI's Sequence Run Archive (SRA). We grouped datasets from the same tissue into their own collection and examined each group separately. We found that a given tRNA produces different groups of co-expressed 5'-tRHs in different tissues, different cell lines, and different diseases. Importantly, the co-expressed 5'-tRHs differ in their sequences, absolute abundances, and relative abundances, even among tRNAs with near-identical sequences from the same isodecoder or isoacceptor group. The findings suggest that co-expressed 5'-tRHs that are produced from the same tRNA or closely related tRNAs have distinct, context-dependent roles. Moreover, our analyses show that cell lines modeling the same tissue type and disease may not be interchangeable when it comes to experimenting with tRFs.
Collapse
Affiliation(s)
| | | | | | | | | | - Isidore Rigoutsos
- Computational Medical Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
| |
Collapse
|
8
|
Dos Santos GA, Chatsirisupachai K, Avelar RA, de Magalhães JP. Transcriptomic analysis reveals a tissue-specific loss of identity during ageing and cancer. BMC Genomics 2023; 24:644. [PMID: 37884865 PMCID: PMC10604446 DOI: 10.1186/s12864-023-09756-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 10/20/2023] [Indexed: 10/28/2023] Open
Abstract
INTRODUCTION Understanding changes in cell identity in cancer and ageing is of great importance. In this work, we analyzed how gene expression changes in human tissues are associated with tissue specificity during cancer and ageing using transcriptome data from TCGA and GTEx. RESULTS We found significant downregulation of tissue-specific genes during ageing in 40% of the tissues analyzed, which suggests loss of tissue identity with age. For most cancer types, we have noted a consistent pattern of downregulation in genes that are specific to the tissue from which the tumor originated. Moreover, we observed in cancer an activation of genes not usually expressed in the tissue of origin as well as an upregulation of genes specific to other tissues. These patterns in cancer were associated with patient survival. The age of the patient, however, did not influence these patterns. CONCLUSION We identified loss of cellular identity in 40% of the tissues analysed during human ageing, and a clear pattern in cancer, where during tumorigenesis cells express genes specific to other organs while suppressing the expression of genes from their original tissue. The loss of cellular identity observed in cancer is associated with prognosis and is not influenced by age, suggesting that it is a crucial stage in carcinogenesis.
Collapse
Affiliation(s)
- Gabriel Arantes Dos Santos
- Laboratory of Medical Investigation (LIM55), Urology Department, Faculdade de Medicina FMUSP, Universidade de Sao Paulo, Sao Paulo, Brazil
- Genomics of Ageing and Rejuvenation Lab, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, B15 2WB, UK
| | - Kasit Chatsirisupachai
- Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, L7 8TX, UK
| | - Roberto A Avelar
- Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, L7 8TX, UK
| | - João Pedro de Magalhães
- Genomics of Ageing and Rejuvenation Lab, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, B15 2WB, UK.
| |
Collapse
|
9
|
Davyt M, Bharti N, Ignatova Z. Effect of mRNA/tRNA mutations on translation speed: Implications for human diseases. J Biol Chem 2023; 299:105089. [PMID: 37495112 PMCID: PMC10470029 DOI: 10.1016/j.jbc.2023.105089] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Revised: 07/18/2023] [Accepted: 07/20/2023] [Indexed: 07/28/2023] Open
Abstract
Recent discoveries establish tRNAs as central regulators of mRNA translation dynamics, and therefore cotranslational folding and function of the encoded protein. The tRNA pool, whose composition and abundance change in a cell- and tissue-dependent manner, is the main factor which determines mRNA translation velocity. In this review, we discuss a group of pathogenic mutations, in the coding sequences of either protein-coding genes or in tRNA genes, that alter mRNA translation dynamics. We also summarize advances in tRNA biology that have uncovered how variations in tRNA levels on account of genetic mutations affect protein folding and function, and thereby contribute to phenotypic diversity in clinical manifestations.
Collapse
Affiliation(s)
- Marcos Davyt
- Institute of Biochemistry and Molecular Biology, University of Hamburg, Hamburg, Germany
| | - Nikhil Bharti
- Institute of Biochemistry and Molecular Biology, University of Hamburg, Hamburg, Germany
| | - Zoya Ignatova
- Institute of Biochemistry and Molecular Biology, University of Hamburg, Hamburg, Germany.
| |
Collapse
|
10
|
Stewart RK, Nguyen P, Laederach A, Volkan PC, Sawyer JK, Fox DT. Orb2 enables rare-codon-enriched mRNA expression during Drosophila neuron differentiation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.26.550700. [PMID: 37546801 PMCID: PMC10402044 DOI: 10.1101/2023.07.26.550700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
Regulation of codon optimality is an increasingly appreciated layer of cell- and tissue-specific protein expression control. Here, we use codon-modified reporters to show that differentiation of Drosophila neural stem cells into neurons enables protein expression from rare-codon-enriched genes. From a candidate screen, we identify the cytoplasmic polyadenylation element binding (CPEB) protein Orb2 as a positive regulator of rare-codon-dependent expression in neurons. Using RNA sequencing, we reveal that Orb2-upregulated mRNAs in the brain with abundant Orb2 binding sites have a rare-codon bias. From these Orb2-regulated mRNAs, we demonstrate that rare-codon enrichment is important for expression control and social behavior function of the metabotropic glutamate receptor (mGluR). Our findings reveal a molecular mechanism by which neural stem cell differentiation shifts genetic code regulation to enable critical mRNA and protein expression.
Collapse
|
11
|
Yague-Sanz C, Migeot V, Larochelle M, Bachand F, Wéry M, Morillon A, Hermand D. Chromatin remodeling by Pol II primes efficient Pol III transcription. Nat Commun 2023; 14:3587. [PMID: 37328480 PMCID: PMC10276017 DOI: 10.1038/s41467-023-39387-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 06/09/2023] [Indexed: 06/18/2023] Open
Abstract
The packaging of the genetic material into chromatin imposes the remodeling of this barrier to allow efficient transcription. RNA polymerase II activity is coupled with several histone modification complexes that enforce remodeling. How RNA polymerase III (Pol III) counteracts the inhibitory effect of chromatin is unknown. We report here a mechanism where RNA Polymerase II (Pol II) transcription is required to prime and maintain nucleosome depletion at Pol III loci and contributes to efficient Pol III recruitment upon re-initiation of growth from stationary phase in Fission yeast. The Pcr1 transcription factor participates in the recruitment of Pol II, which affects local histone occupancy through the associated SAGA complex and a Pol II phospho-S2 CTD / Mst2 pathway. These data expand the central role of Pol II in gene expression beyond mRNA synthesis.
Collapse
Affiliation(s)
- Carlo Yague-Sanz
- URPHYM-GEMO, The University of Namur, rue de Bruxelles, 61, Namur, 5000, Belgium
| | - Valérie Migeot
- URPHYM-GEMO, The University of Namur, rue de Bruxelles, 61, Namur, 5000, Belgium
| | - Marc Larochelle
- RNA Group, Department of Biochemistry and Functional Genomics, Université de Sherbrooke, Sherbrooke, QC, J1E 4K8, Canada
| | - François Bachand
- RNA Group, Department of Biochemistry and Functional Genomics, Université de Sherbrooke, Sherbrooke, QC, J1E 4K8, Canada
| | - Maxime Wéry
- ncRNA, Epigenetic and Genome Fluidity, Institut Curie, PSL Research University, Université Pierre et Marie Curie, CNRS UMR 3244, Paris, France
| | - Antonin Morillon
- ncRNA, Epigenetic and Genome Fluidity, Institut Curie, PSL Research University, Université Pierre et Marie Curie, CNRS UMR 3244, Paris, France
| | - Damien Hermand
- URPHYM-GEMO, The University of Namur, rue de Bruxelles, 61, Namur, 5000, Belgium.
| |
Collapse
|
12
|
Tyczewska A, Rzepczak A, Sobańska D, Grzywacz K. The emerging roles of tRNAs and tRNA-derived fragments during aging: Lessons from studies on model organisms. Ageing Res Rev 2023; 85:101863. [PMID: 36707034 DOI: 10.1016/j.arr.2023.101863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 01/19/2023] [Accepted: 01/23/2023] [Indexed: 01/26/2023]
Abstract
Aging is a gradual decline of various functions of organisms resulting in diminished abilities to protect against the environmental damage and reinforce the physiological harmony. Age-related functional declines have been thought to be passive and not regulated. However, studies on numerous model organisms, from yeast to mammals, exposed that the mechanisms of lifespan regulation are remarkably conserved throughout the evolution. Following the pioneering genetic studies in C. elegans, it has been shown that the genes related to the longevity are conserved in yeast, flies and mice. For a long time, tRNAs have been only considered as molecules transporting amino acids to the ribosome during translation. Nonetheless, it has become apparent from many biological studies that tRNAs are entangled in a variety of physiological and pathological processes. This review focuses on the emerging roles of tRNA-associated processes in aging and lifespan of model organisms. More specificaly, we present a summary on the importance of tRNA metabolism, epitranscriptome and possible roles of tRNA-derived fragments in aging and lifespan regulation. Better understanding of the basic mechanisms of aging could lead to the development of new diagnostics and treatments for aging-related diseases.
Collapse
Affiliation(s)
- Agata Tyczewska
- Institute of Bioorganic Chemistry Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznań, Poland
| | - Alicja Rzepczak
- Institute of Bioorganic Chemistry Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznań, Poland
| | - Daria Sobańska
- Institute of Bioorganic Chemistry Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznań, Poland
| | - Kamilla Grzywacz
- Institute of Bioorganic Chemistry Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznań, Poland.
| |
Collapse
|
13
|
Scheepbouwer C, Aparicio-Puerta E, Gomez-Martin C, Verschueren H, van Eijndhoven M, Wedekind LE, Giannoukakos S, Hijmering N, Gasparotto L, van der Galien HT, van Rijn RS, Aronica E, Kibbelaar R, Heine VM, Wesseling P, Noske DP, Vandertop WP, de Jong D, Pegtel DM, Hackenberg M, Wurdinger T, Gerber A, Koppers-Lalic D. ALL-tRNAseq enables robust tRNA profiling in tissue samples. Genes Dev 2023; 37:243-257. [PMID: 36810209 PMCID: PMC10111867 DOI: 10.1101/gad.350233.122] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 01/26/2023] [Indexed: 02/23/2023]
Abstract
Transfer RNAs (tRNAs) are small adaptor RNAs essential for mRNA translation. Alterations in the cellular tRNA population can directly affect mRNA decoding rates and translational efficiency during cancer development and progression. To evaluate changes in the composition of the tRNA pool, multiple sequencing approaches have been developed to overcome reverse transcription blocks caused by the stable structures of these molecules and their numerous base modifications. However, it remains unclear whether current sequencing protocols faithfully capture tRNAs existing in cells or tissues. This is specifically challenging for clinical tissue samples that often present variable RNA qualities. For this reason, we developed ALL-tRNAseq, which combines the highly processive MarathonRT and RNA demethylation for the robust assessment of tRNA expression, together with a randomized adapter ligation strategy prior to reverse transcription to assess tRNA fragmentation levels in both cell lines and tissues. Incorporation of tRNA fragments not only informed on sample integrity but also significantly improved tRNA profiling of tissue samples. Our data showed that our profiling strategy effectively improves classification of oncogenic signatures in glioblastoma and diffuse large B-cell lymphoma tissues, particularly for samples presenting higher levels of RNA fragmentation, further highlighting the utility of ALL-tRNAseq for translational research.
Collapse
Affiliation(s)
- Chantal Scheepbouwer
- Department of Neurosurgery, Cancer Center Amsterdam, Amsterdam University Medical Center (UMC) location Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands;
- Brain Tumor Center Amsterdam, Amsterdam UMC location Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
- Department of Pathology, Cancer Center Amsterdam, Amsterdam UMC location Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
| | | | - Cristina Gomez-Martin
- Department of Pathology, Cancer Center Amsterdam, Amsterdam UMC location Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
| | - Heleen Verschueren
- Department of Neurosurgery, Cancer Center Amsterdam, Amsterdam University Medical Center (UMC) location Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
- Brain Tumor Center Amsterdam, Amsterdam UMC location Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
| | - Monique van Eijndhoven
- Department of Pathology, Cancer Center Amsterdam, Amsterdam UMC location Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
| | - Laurine E Wedekind
- Department of Neurosurgery, Cancer Center Amsterdam, Amsterdam University Medical Center (UMC) location Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
- Brain Tumor Center Amsterdam, Amsterdam UMC location Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
| | - Stavros Giannoukakos
- Genetics Department, Faculty of Science, University of Granada, 18071 Granada, Spain
| | - Nathalie Hijmering
- Department of Pathology, Cancer Center Amsterdam, Amsterdam UMC location Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
| | - Lisa Gasparotto
- Department of Child and Adolescent Psychiatry, Emma Children's Hospital, Amsterdam UMC, Neuroscience, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
| | - Hilde T van der Galien
- Department of Hematology, Medical Center Leeuwarden, 8934 AD Leeuwarden, the Netherlands
- HemoBase Population Registry Consortium, 8934 AD Leeuwarden, the Netherlands
| | - Roos S van Rijn
- Department of Hematology, Medical Center Leeuwarden, 8934 AD Leeuwarden, the Netherlands
- HemoBase Population Registry Consortium, 8934 AD Leeuwarden, the Netherlands
| | - Eleonora Aronica
- Department of (Neuro)Pathology Amsterdam Neuroscience, Amsterdam UMC location University of Amsterdam, 1105 AZ Amsterdam, the Netherlands
| | - Robby Kibbelaar
- HemoBase Population Registry Consortium, 8934 AD Leeuwarden, the Netherlands
- Department of Pathology, Pathology Friesland, 8917 EN Leeuwarden, the Netherlands
| | - Vivi M Heine
- Department of Child and Adolescent Psychiatry, Emma Children's Hospital, Amsterdam UMC, Neuroscience, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
- Department of Complex Trait Genetics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
| | - Pieter Wesseling
- Department of Pathology, Cancer Center Amsterdam, Amsterdam UMC location Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
- Laboratory for Childhood Cancer Pathology, Princess Máxima Center for Pediatric Oncology, University Medical Center Utrecht, 3584 CS Utrecht, the Netherlands
| | - David P Noske
- Department of Neurosurgery, Cancer Center Amsterdam, Amsterdam University Medical Center (UMC) location Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
- Brain Tumor Center Amsterdam, Amsterdam UMC location Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
| | - W Peter Vandertop
- Department of Neurosurgery, Cancer Center Amsterdam, Amsterdam University Medical Center (UMC) location Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
- Brain Tumor Center Amsterdam, Amsterdam UMC location Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
| | - Daphne de Jong
- Department of Pathology, Cancer Center Amsterdam, Amsterdam UMC location Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
| | - D Michiel Pegtel
- Department of Pathology, Cancer Center Amsterdam, Amsterdam UMC location Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
| | - Michael Hackenberg
- Genetics Department, Faculty of Science, University of Granada, 18071 Granada, Spain
| | - Tom Wurdinger
- Department of Neurosurgery, Cancer Center Amsterdam, Amsterdam University Medical Center (UMC) location Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
- Brain Tumor Center Amsterdam, Amsterdam UMC location Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
| | - Alan Gerber
- Department of Neurosurgery, Cancer Center Amsterdam, Amsterdam University Medical Center (UMC) location Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
- Brain Tumor Center Amsterdam, Amsterdam UMC location Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
| | - Danijela Koppers-Lalic
- Department of Neurosurgery, Cancer Center Amsterdam, Amsterdam University Medical Center (UMC) location Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands;
- Brain Tumor Center Amsterdam, Amsterdam UMC location Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
| |
Collapse
|
14
|
Watt KE, Macintosh J, Bernard G, Trainor PA. RNA Polymerases I and III in development and disease. Semin Cell Dev Biol 2023; 136:49-63. [PMID: 35422389 PMCID: PMC9550887 DOI: 10.1016/j.semcdb.2022.03.027] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 03/18/2022] [Accepted: 03/21/2022] [Indexed: 12/18/2022]
Abstract
Ribosomes are macromolecular machines that are globally required for the translation of all proteins in all cells. Ribosome biogenesis, which is essential for cell growth, proliferation and survival, commences with transcription of a variety of RNAs by RNA Polymerases I and III. RNA Polymerase I (Pol I) transcribes ribosomal RNA (rRNA), while RNA Polymerase III (Pol III) transcribes 5S ribosomal RNA and transfer RNAs (tRNA) in addition to a wide variety of small non-coding RNAs. Interestingly, despite their global importance, disruptions in Pol I and Pol III function result in tissue-specific developmental disorders, with craniofacial anomalies and leukodystrophy/neurodegenerative disease being among the most prevalent. Furthermore, pathogenic variants in genes encoding subunits shared between Pol I and Pol III give rise to distinct syndromes depending on whether Pol I or Pol III function is disrupted. In this review, we discuss the global roles of Pol I and III transcription, the consequences of disruptions in Pol I and III transcription, disorders arising from pathogenic variants in Pol I and Pol III subunits, and mechanisms underpinning their tissue-specific phenotypes.
Collapse
Affiliation(s)
- Kristin En Watt
- Stowers Institute for Medical Research, Kansas City, MO, USA
| | - Julia Macintosh
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada; Child Health and Human Development Program, Research Institute of the McGill University Health Center, Montreal, QC, Canada
| | - Geneviève Bernard
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada; Child Health and Human Development Program, Research Institute of the McGill University Health Center, Montreal, QC, Canada; Departments of Pediatrics and Human Genetics, McGill University, Montreal, QC, Canada; Department of Specialized Medicine, Division of Medical Genetics, McGill University Health Center, Montreal, QC, Canada.
| | - Paul A Trainor
- Stowers Institute for Medical Research, Kansas City, MO, USA; Department of Anatomy & Cell Biology, University of Kansas Medical Center, Kansas City, KS, USA.
| |
Collapse
|
15
|
Codon optimality has minimal effect on determining translation efficiency in mycobacterium tuberculosis. Sci Rep 2023; 13:415. [PMID: 36624167 PMCID: PMC9829911 DOI: 10.1038/s41598-022-27164-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2022] [Accepted: 12/27/2022] [Indexed: 01/11/2023] Open
Abstract
Mycobacterium tuberculosis (Mtb) is a slow-growing, intracellular pathogen that exhibits a high GC-rich genome. Several factors, including the GC content of the genome, influence the evolution of specific codon usage biases in genomes. As a result, the Mtb genome exhibits strong biases for amino acid usage and codon usage. Codon usage of mRNAs affects several aspects of translation, including accuracy, efficiency, and protein folding. Here we address the effect of codon usage biases in determining the translation efficiency of mRNAs in Mtb. Unlike most commonly studied organisms, Mtb carries a single copy of each tRNA gene. However, we show that the relative levels of tRNAs in the Mtb tRNA pool vary by an order of magnitude. Our results show that the codons decoded by the abundant tRNAs indeed show higher adaptability. Moreover, there is a general positive correlation between genomic codon usage and the tRNA adaptability of codons (TAc). We further estimated the optimality of the codon and mRNAs by considering both the TAc and the tRNA demand. These measures did not show any correlation with mRNA abundance and translation efficiency. There was no correlation between tRNA adaptability and ribosome pausing as well. Taken together, we conclude that the translation machinery, and the tRNA pool of an organism, co-evolve with the codon usage to optimize the translation efficiency of an organism. Thus the deleterious effect of maladapted codons is not pronounced.
Collapse
|
16
|
Dysfunctional tRNA reprogramming and codon-biased translation in cancer. Trends Mol Med 2022; 28:964-978. [PMID: 36241532 PMCID: PMC10071289 DOI: 10.1016/j.molmed.2022.09.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Revised: 08/20/2022] [Accepted: 09/12/2022] [Indexed: 12/17/2022]
Abstract
Many cancers hijack translation to increase the synthesis of tumor-driving proteins, the messenger mRNAs of which have specific codon usage patterns. Termed 'codon-biased translation' and originally identified in stress response regulation, this mechanism is supported by diverse studies demonstrating how the 50 RNA modifications of the epitranscriptome, specific tRNAs, and codon-biased mRNAs are used by oncogenic programs to promote proliferation and chemoresistance. The epitranscriptome writers METTL1-WDR4, Elongator complex protein (ELP)1-6, CTU1-2, and ALKBH8-TRM112 illustrate the principal mechanism of codon-biased translation, with gene amplifications, increased RNA modifications, and enhanced tRNA stability promoting cancer proliferation. Furthermore, systems-level analyses of 34 tRNA writers and 493 tRNA genes highlight the theme of tRNA epitranscriptome dysregulation in many cancers and identify candidate tRNA writers, tRNA modifications, and tRNA molecules as drivers of pathological codon-biased translation.
Collapse
|
17
|
Martin S, Allan KC, Pinkard O, Sweet T, Tesar PJ, Coller J. Oligodendrocyte differentiation alters tRNA modifications and codon optimality-mediated mRNA decay. Nat Commun 2022; 13:5003. [PMID: 36008413 PMCID: PMC9411196 DOI: 10.1038/s41467-022-32766-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 08/15/2022] [Indexed: 11/08/2022] Open
Abstract
Oligodendrocytes are specialized cells that confer neuronal myelination in the central nervous system. Leukodystrophies associated with oligodendrocyte deficits and hypomyelination are known to result when a number of tRNA metabolism genes are mutated. Thus, for unknown reasons, oligodendrocytes may be hypersensitive to perturbations in tRNA biology. In this study, we survey the tRNA transcriptome in the murine oligodendrocyte cell lineage and find that specific tRNAs are hypomodified in oligodendrocytes within or near the anticodon compared to oligodendrocyte progenitor cells (OPCs). This hypomodified state may be the result of differential expression of key modification enzymes during oligodendrocyte differentiation. Moreover, we observe a concomitant relationship between tRNA hypomodification and tRNA decoding potential; observing oligodendrocyte specific alterations in codon optimality-mediated mRNA decay and ribosome transit. Our results reveal that oligodendrocytes naturally maintain a delicate, hypersensitized tRNA/mRNA axis. We suggest this axis is a potential mediator of pathology in leukodystrophies and white matter disease when further insult to tRNA metabolism is introduced.
Collapse
Affiliation(s)
- Sophie Martin
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Kevin C Allan
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA
| | - Otis Pinkard
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA
| | - Thomas Sweet
- Center for Proteomics and Bioinformatics, Department of Nutrition, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA
| | - Paul J Tesar
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA
| | - Jeff Coller
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- Department of Biology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
| |
Collapse
|
18
|
Miller JB, Meurs TE, Hodgman MW, Song B, Miller KN, Ebbert MTW, Kauwe JSK, Ridge PG. The Ramp Atlas: facilitating tissue and cell-specific ramp sequence analyses through an intuitive web interface. NAR Genom Bioinform 2022; 4:lqac039. [PMID: 35664804 PMCID: PMC9155233 DOI: 10.1093/nargab/lqac039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 03/01/2022] [Accepted: 05/24/2022] [Indexed: 11/14/2022] Open
Abstract
Ramp sequences occur when the average translational efficiency of codons near the 5′ end of highly expressed genes is significantly lower than the rest of the gene sequence, which counterintuitively increases translational efficiency by decreasing downstream ribosomal collisions. Here, we show that the relative codon adaptiveness within different tissues changes the existence of a ramp sequence without altering the underlying genetic code. We present the first comprehensive analysis of tissue and cell type-specific ramp sequences and report 3108 genes with ramp sequences that change between tissues and cell types, which corresponds with increased gene expression within those tissues and cells. The Ramp Atlas (https://ramps.byu.edu/) allows researchers to query precomputed ramp sequences in 18 388 genes across 62 tissues and 66 cell types and calculate tissue-specific ramp sequences from user-uploaded FASTA files through an intuitive web interface. We used The Ramp Atlas to identify seven SARS-CoV-2 genes and seven human SARS-CoV-2 entry factor genes with tissue-specific ramp sequences that may help explain viral proliferation within those tissues. We anticipate that The Ramp Atlas will facilitate personalized and creative tissue-specific ramp sequence analyses for both human and viral genes that will increase our ability to utilize this often-overlooked regulatory region.
Collapse
Affiliation(s)
- Justin B Miller
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY 40504, USA
| | - Taylor E Meurs
- Department of Biology, Brigham Young University, Provo, UT 84602, USA
| | - Matthew W Hodgman
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY 40504, USA
| | - Benjamin Song
- Department of Biology, Brigham Young University, Provo, UT 84602, USA
| | - Kyle N Miller
- Department of Computer Science, Utah Valley University, Orem, UT 84058, USA
| | - Mark T W Ebbert
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY 40504, USA
| | - John S K Kauwe
- Department of Biology, Brigham Young University, Provo, UT 84602, USA
| | - Perry G Ridge
- Department of Biology, Brigham Young University, Provo, UT 84602, USA
| |
Collapse
|
19
|
Lee AK, Aifantis I, Thandapani P. Emerging roles for tRNAs in hematopoiesis and hematological malignancies. Trends Immunol 2022; 43:466-477. [PMID: 35490133 DOI: 10.1016/j.it.2022.03.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 03/30/2022] [Accepted: 03/31/2022] [Indexed: 11/26/2022]
Abstract
tRNAs are central players in decoding the genetic code linking codons in mRNAs with cognate amino acids during protein synthesis. Recent discoveries have placed tRNAs as key regulators of gene expression during hematopoiesis, especially in hematopoietic stem cell (HSC) maintenance and immune development. These functions have been shown to be influenced by dynamic changes in tRNA expression, post-transcriptional base modifications, tRNA-interacting proteins, and tRNA fragmentation; these events underlie the complexity of tRNA-mediated regulatory events in hematopoiesis. In this review, we discuss these recent findings and highlight how deregulation of tRNA biogenesis can contribute to hematological malignancies.
Collapse
Affiliation(s)
- Anna K Lee
- Department of Pathology and Laura and Isaac Perlmutter Cancer Center, NYU School of Medicine, New York, NY 10016, USA
| | - Iannis Aifantis
- Department of Pathology and Laura and Isaac Perlmutter Cancer Center, NYU School of Medicine, New York, NY 10016, USA.
| | - Palaniraja Thandapani
- Department of Pathology and Laura and Isaac Perlmutter Cancer Center, NYU School of Medicine, New York, NY 10016, USA.
| |
Collapse
|
20
|
Alsop E, Meechoovet B, Kitchen R, Sweeney T, Beach TG, Serrano GE, Hutchins E, Ghiran I, Reiman R, Syring M, Hsieh M, Courtright-Lim A, Valkov N, Whitsett TG, Rakela J, Pockros P, Rozowsky J, Gallego J, Huentelman MJ, Shah R, Nakaji P, Kalani MYS, Laurent L, Das S, Van Keuren-Jensen K. A Novel Tissue Atlas and Online Tool for the Interrogation of Small RNA Expression in Human Tissues and Biofluids. Front Cell Dev Biol 2022; 10:804164. [PMID: 35317387 PMCID: PMC8934391 DOI: 10.3389/fcell.2022.804164] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 01/28/2022] [Indexed: 12/20/2022] Open
Abstract
One promising goal for utilizing the molecular information circulating in biofluids is the discovery of clinically useful biomarkers. Extracellular RNAs (exRNAs) are one of the most diverse classes of molecular cargo, easily assayed by sequencing and with expressions that rapidly change in response to subject status. Despite diverse exRNA cargo, most evaluations from biofluids have focused on small RNA sequencing and analysis, specifically on microRNAs (miRNAs). Another goal of characterizing circulating molecular information, is to correlate expression to injuries associated with specific tissues of origin. Biomarker candidates are often described as being specific, enriched in a particular tissue or associated with a disease process. Likewise, miRNA data is often reported to be specific, enriched for a tissue, without rigorous testing to support the claim. Here we provide a tissue atlas of small RNAs from 30 different tissues and three different blood cell types. We analyzed the tissues for enrichment of small RNA sequences and assessed their expression in biofluids: plasma, cerebrospinal fluid, urine, and saliva. We employed published data sets representing physiological (resting vs. acute exercise) and pathologic states (early- vs. late-stage liver fibrosis, and differential subtypes of stroke) to determine differential tissue-enriched small RNAs. We also developed an online tool that provides information about exRNA sequences found in different biofluids and tissues. The data can be used to better understand the various types of small RNA sequences in different tissues as well as their potential release into biofluids, which should help in the validation or design of biomarker studies.
Collapse
Affiliation(s)
- Eric Alsop
- Neurogenomics Division, The Translational Genomics Research Institute, Phoenix, AZ, United States
| | - Bessie Meechoovet
- Neurogenomics Division, The Translational Genomics Research Institute, Phoenix, AZ, United States
| | - Robert Kitchen
- Cardiovascular Research Center, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States
| | - Thadryan Sweeney
- Cardiovascular Research Center, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States
| | - Thomas G. Beach
- Banner Sun Health Research Institute, Sun City, AZ, United States
| | - Geidy E. Serrano
- Banner Sun Health Research Institute, Sun City, AZ, United States
| | - Elizabeth Hutchins
- Neurogenomics Division, The Translational Genomics Research Institute, Phoenix, AZ, United States
| | - Ionita Ghiran
- Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, United States
| | - Rebecca Reiman
- Neurogenomics Division, The Translational Genomics Research Institute, Phoenix, AZ, United States
| | - Michael Syring
- Neurogenomics Division, The Translational Genomics Research Institute, Phoenix, AZ, United States
| | - Michael Hsieh
- Neurogenomics Division, The Translational Genomics Research Institute, Phoenix, AZ, United States
| | - Amanda Courtright-Lim
- Neurogenomics Division, The Translational Genomics Research Institute, Phoenix, AZ, United States
| | - Nedyalka Valkov
- Cardiovascular Research Center, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States
| | - Timothy G. Whitsett
- Neurogenomics Division, The Translational Genomics Research Institute, Phoenix, AZ, United States
| | | | - Paul Pockros
- Division of Gastroenterology/Hepatology, Scripps Clinic, La Jolla, CA, United States
| | - Joel Rozowsky
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, United States
| | - Juan Gallego
- Institute for Behavioral Science, The Feinstein Institute for Medical Research, Manhasset, NY, United States
- Division of Psychiatry Research, The Zucker Hillside Hospital, Glen Oaks, NY, United States
- Department of Psychiatry, Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, United States
| | - Matthew J. Huentelman
- Neurogenomics Division, The Translational Genomics Research Institute, Phoenix, AZ, United States
| | - Ravi Shah
- Cardiovascular Research Center, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States
| | - Peter Nakaji
- Department of Neurosurgery, Banner Health, Phoenix, AZ, United States
| | - M. Yashar S. Kalani
- Department of Neurosurgery, St. John Medical Center, Tulsa, OK, United States
| | - Louise Laurent
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Diego, San Diego, CA, United States
| | - Saumya Das
- Cardiovascular Research Center, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States
| | | |
Collapse
|
21
|
Dynamic changes in tRNA modifications and abundance during T cell activation. Proc Natl Acad Sci U S A 2021; 118:2106556118. [PMID: 34642250 DOI: 10.1073/pnas.2106556118] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/28/2021] [Indexed: 12/13/2022] Open
Abstract
The tRNA pool determines the efficiency, throughput, and accuracy of translation. Previous studies have identified dynamic changes in the tRNA (transfer RNA) supply and mRNA (messenger RNA) demand during cancerous proliferation. Yet dynamic changes may also occur during physiologically normal proliferation, and these are less well characterized. We examined the tRNA and mRNA pools of T cells during their vigorous proliferation and differentiation upon triggering their antigen receptor. We observed a global signature of switch in demand for codons at the early proliferation phase of the response, accompanied by corresponding changes in tRNA expression levels. In the later phase, upon differentiation, the response of the tRNA pool relaxed back to the basal level, potentially restraining excessive proliferation. Sequencing of tRNAs allowed us to evaluate their diverse base-modifications. We found that two types of tRNA modifications, wybutosine and ms2t6A, are reduced dramatically during T cell activation. These modifications occur in the anticodon loops of two tRNAs that decode "slippery codons," which are prone to ribosomal frameshifting. Attenuation of these frameshift-protective modifications is expected to increase the potential for proteome-wide frameshifting during T cell proliferation. Indeed, human cell lines deleted of a wybutosine writer showed increased ribosomal frameshifting, as detected with an HIV gag-pol frameshifting site reporter. These results may explain HIV's specific tropism toward proliferating T cells since it requires ribosomal frameshift exactly on the corresponding codon for infection. The changes in tRNA expression and modifications uncover a layer of translation regulation during T cell proliferation and expose a potential tradeoff between cellular growth and translation fidelity.
Collapse
|
22
|
DBtRend: A Web-Server of tRNA Expression Profiles from Small RNA Sequencing Data in Humans. Genes (Basel) 2021; 12:genes12101576. [PMID: 34680971 PMCID: PMC8535304 DOI: 10.3390/genes12101576] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 09/29/2021] [Accepted: 10/01/2021] [Indexed: 01/04/2023] Open
Abstract
Transfer RNA (tRNA), a key component of the translation machinery, plays critical roles in stress conditions and various diseases. While knowledge regarding the importance of tRNA function is increasing, its biological roles are still not well understood. There is currently no comprehensive database or web server providing the expression landscape of tRNAs across a variety of human tissues and diseases. Here, we constructed a user-friendly and interactive database, DBtRend, which provides a profile of mature tRNA expression across various biological conditions by reanalyzing the small RNA or microRNA sequencing data from the Cancer Genome Atlas (TCGA) and NCBI's Gene Expression Omnibus (GEO) in humans. Users can explore not only the expression values of mature individual tRNAs in the human genome, but also those of isodecoders and isoacceptors based on our specific pipelines. DBtRend provides the expressed patterns of tRNAs, the differentially expressed tRNAs in different biological conditions, and the information of samples or patients, tissue types, and molecular subtype of cancers. The database is expected to help researchers interested in functional discoveries of tRNAs.
Collapse
|
23
|
Santamaría-Gómez J, Rubio MÁ, López-Igual R, Romero-Losada AB, Delgado-Chaves FM, Bru-Martínez R, Romero-Campero FJ, Herrero A, Ibba M, Ochoa de Alda JAG, Luque I. Role of a cryptic tRNA gene operon in survival under translational stress. Nucleic Acids Res 2021; 49:8757-8776. [PMID: 34379789 PMCID: PMC8421152 DOI: 10.1093/nar/gkab661] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 07/12/2021] [Accepted: 07/22/2021] [Indexed: 01/08/2023] Open
Abstract
As compared to eukaryotes, bacteria have a reduced tRNA gene set encoding between 30 and 220 tRNAs. Although in most bacterial phyla tRNA genes are dispersed in the genome, many species from distinct phyla also show genes forming arrays. Here, we show that two types of arrays with distinct evolutionary origins exist. This work focuses on long tRNA gene arrays (L-arrays) that encompass up to 43 genes, which disseminate by horizontal gene transfer and contribute supernumerary tRNA genes to the host. Although in the few cases previously studied these arrays were reported to be poorly transcribed, here we show that the L-array of the model cyanobacterium Anabaena sp. PCC 7120, encoding 23 functional tRNAs, is largely induced upon impairment of the translation machinery. The cellular response to this challenge involves a global reprogramming of the transcriptome in two phases. tRNAs encoded in the array are induced in the second phase of the response, directly contributing to cell survival. Results presented here show that in some bacteria the tRNA gene set may be partitioned between a housekeeping subset, which constantly sustains translation, and an inducible subset that is generally silent but can provide functionality under particular conditions.
Collapse
Affiliation(s)
- Javier Santamaría-Gómez
- Instituto de Bioquímica Vegetal y Fotosíntesis, C.S.I.C. and Universidad de Sevilla, Seville E-41092, Spain
| | - Miguel Ángel Rubio
- Instituto de Bioquímica Vegetal y Fotosíntesis, C.S.I.C. and Universidad de Sevilla, Seville E-41092, Spain.,Center for RNA Biology, The Ohio State University, 484 West 12th Avenue, Columbus, OH 43210, USA.,Department of Microbiology, The Ohio State University, 318 West 12th Avenue, Columbus, OH 43210, USA
| | - Rocío López-Igual
- Instituto de Bioquímica Vegetal y Fotosíntesis, C.S.I.C. and Universidad de Sevilla, Seville E-41092, Spain
| | - Ana B Romero-Losada
- Instituto de Bioquímica Vegetal y Fotosíntesis, C.S.I.C. and Universidad de Sevilla, Seville E-41092, Spain.,Department of Computer Science and Artificial Intelligence, Universidad de Sevilla, Seville E-41012, Spain
| | - Fernando M Delgado-Chaves
- Instituto de Bioquímica Vegetal y Fotosíntesis, C.S.I.C. and Universidad de Sevilla, Seville E-41092, Spain
| | - Roque Bru-Martínez
- Department of Agrochemistry and Biochemistry, Faculty of Science, University of Alicante, Alicante E- 03690, Spain
| | - Francisco J Romero-Campero
- Instituto de Bioquímica Vegetal y Fotosíntesis, C.S.I.C. and Universidad de Sevilla, Seville E-41092, Spain.,Department of Computer Science and Artificial Intelligence, Universidad de Sevilla, Seville E-41012, Spain
| | - Antonia Herrero
- Instituto de Bioquímica Vegetal y Fotosíntesis, C.S.I.C. and Universidad de Sevilla, Seville E-41092, Spain
| | - Michael Ibba
- Center for RNA Biology, The Ohio State University, 484 West 12th Avenue, Columbus, OH 43210, USA.,Department of Microbiology, The Ohio State University, 318 West 12th Avenue, Columbus, OH 43210, USA.,Schmid College of Science and Technology, Chapman University, One University Drive, Orange, CA 92866, USA
| | - Jesús A G Ochoa de Alda
- Didáctica de las Ciencias Experimentales, Facultad de Formación del Profesorado, Universidad de Extremadura, Cáceres E-10003, Spain
| | - Ignacio Luque
- Instituto de Bioquímica Vegetal y Fotosíntesis, C.S.I.C. and Universidad de Sevilla, Seville E-41092, Spain
| |
Collapse
|
24
|
Bergeron D, Laforest C, Carpentier S, Calvé A, Fafard-Couture É, Deschamps-Francoeur G, Scott MS. SnoRNA copy regulation affects family size, genomic location and family abundance levels. BMC Genomics 2021; 22:414. [PMID: 34090325 PMCID: PMC8178906 DOI: 10.1186/s12864-021-07757-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 05/26/2021] [Indexed: 12/03/2022] Open
Abstract
Background Small nucleolar RNAs (snoRNAs) are an abundant class of noncoding RNAs present in all eukaryotes and best known for their involvement in ribosome biogenesis. In mammalian genomes, many snoRNAs exist in multiple copies, resulting from recombination and retrotransposition from an ancestral snoRNA. To gain insight into snoRNA copy regulation, we used Rfam classification and normal human tissue expression datasets generated using low structure bias RNA-seq to characterize snoRNA families. Results We found that although box H/ACA families are on average larger than box C/D families, the number of expressed members is similar for both types. Family members can cover a wide range of average abundance values, but importantly, expression variability of individual members of a family is preferred over the total variability of the family, especially for box H/ACA snoRNAs, suggesting that while members are likely differentially regulated, mechanisms exist to ensure uniformity of the total family abundance across tissues. Box C/D snoRNA family members are mostly embedded in the same host gene while box H/ACA family members tend to be encoded in more than one different host, supporting a model in which box C/D snoRNA duplication occurred mostly by cis recombination while box H/ACA snoRNA families have gained copy members through retrotransposition. And unexpectedly, snoRNAs encoded in the same host gene can be regulated independently, as some snoRNAs within the same family vary in abundance in a divergent way between tissues. Conclusions SnoRNA copy regulation affects family sizes, genomic location of the members and controls simultaneously member and total family abundance to respond to the needs of individual tissues. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-021-07757-1.
Collapse
Affiliation(s)
- Danny Bergeron
- Département de biochimie et de génomique fonctionnelle, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Québec, J1E 4K8, Canada
| | - Cédric Laforest
- Département de biochimie et de génomique fonctionnelle, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Québec, J1E 4K8, Canada
| | - Stacey Carpentier
- Département de biochimie et de génomique fonctionnelle, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Québec, J1E 4K8, Canada
| | - Annabelle Calvé
- Département de biochimie et de génomique fonctionnelle, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Québec, J1E 4K8, Canada
| | - Étienne Fafard-Couture
- Département de biochimie et de génomique fonctionnelle, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Québec, J1E 4K8, Canada
| | - Gabrielle Deschamps-Francoeur
- Département de biochimie et de génomique fonctionnelle, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Québec, J1E 4K8, Canada
| | - Michelle S Scott
- Département de biochimie et de génomique fonctionnelle, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Québec, J1E 4K8, Canada.
| |
Collapse
|
25
|
Roles of tRNA metabolism in aging and lifespan. Cell Death Dis 2021; 12:548. [PMID: 34039958 PMCID: PMC8154886 DOI: 10.1038/s41419-021-03838-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 05/11/2021] [Accepted: 05/12/2021] [Indexed: 12/17/2022]
Abstract
Transfer RNAs (tRNAs) mainly function as adapter molecules that decode messenger RNAs (mRNAs) during protein translation by delivering amino acids to the ribosome. Traditionally, tRNAs are considered as housekeepers without additional functions. Nevertheless, it has become apparent from biological research that tRNAs are involved in various physiological and pathological processes. Aging is a form of gradual decline in physiological function that ultimately leads to increased vulnerability to multiple chronic diseases and death. Interestingly, tRNA metabolism is closely associated with aging and lifespan. In this review, we summarize the emerging roles of tRNA-associated metabolism, such as tRNA transcription, tRNA molecules, tRNA modifications, tRNA aminoacylation, and tRNA derivatives, in aging and lifespan, aiming to provide new ideas for developing therapeutics and ultimately extending lifespan in humans.
Collapse
|
26
|
Acton RJ, Yuan W, Gao F, Xia Y, Bourne E, Wozniak E, Bell J, Lillycrop K, Wang J, Dennison E, Harvey NC, Mein CA, Spector TD, Hysi PG, Cooper C, Bell CG. The genomic loci of specific human tRNA genes exhibit ageing-related DNA hypermethylation. Nat Commun 2021; 12:2655. [PMID: 33976121 PMCID: PMC8113476 DOI: 10.1038/s41467-021-22639-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 03/05/2021] [Indexed: 02/03/2023] Open
Abstract
The epigenome has been shown to deteriorate with age, potentially impacting on ageing-related disease. tRNA, while arising from only ˜46 kb (<0.002% genome), is the second most abundant cellular transcript. tRNAs also control metabolic processes known to affect ageing, through core translational and additional regulatory roles. Here, we interrogate the DNA methylation state of the genomic loci of human tRNA. We identify a genomic enrichment for age-related DNA hypermethylation at tRNA loci. Analysis in 4,350 MeDIP-seq peripheral-blood DNA methylomes (16-82 years), identifies 44 and 21 hypermethylating specific tRNAs at study-and genome-wide significance, respectively, contrasting with none hypomethylating. Validation and replication (450k array and independent targeted Bisuphite-sequencing) supported the hypermethylation of this functional unit. Tissue-specificity is a significant driver, although the strongest consistent signals, also independent of major cell-type change, occur in tRNA-iMet-CAT-1-4 and tRNA-Ser-AGA-2-6. This study presents a comprehensive evaluation of the genomic DNA methylation state of human tRNA genes and reveals a discreet hypermethylation with advancing age.
Collapse
Affiliation(s)
- Richard J Acton
- William Harvey Research Institute, Barts & The London School of Medicine and Dentistry, Charterhouse Square, Queen Mary University of London, London, UK
- MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton, UK
- Human Development and Health, Institute of Developmental Sciences, University of Southampton, Southampton, UK
| | - Wei Yuan
- Department of Twin Research & Genetic Epidemiology, St Thomas Hospital, King's College London, London, UK
- Institute of Cancer Research, Sutton, UK
| | - Fei Gao
- BGI-Shenzhen, Shenzhen, China
| | | | - Emma Bourne
- Barts & The London Genome Centre, Blizard Institute, Barts & The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Eva Wozniak
- Barts & The London Genome Centre, Blizard Institute, Barts & The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Jordana Bell
- Department of Twin Research & Genetic Epidemiology, St Thomas Hospital, King's College London, London, UK
| | - Karen Lillycrop
- Human Development and Health, Institute of Developmental Sciences, University of Southampton, Southampton, UK
| | - Jun Wang
- Shenzhen Digital Life Institute, Shenzhen, Guangdong, China
- iCarbonX, Zhuhai, Guangdong, China
- State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Taipa, Macau, China
| | - Elaine Dennison
- MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton, UK
| | - Nicholas C Harvey
- MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton, UK
| | - Charles A Mein
- Barts & The London Genome Centre, Blizard Institute, Barts & The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Tim D Spector
- Department of Twin Research & Genetic Epidemiology, St Thomas Hospital, King's College London, London, UK
| | - Pirro G Hysi
- Department of Twin Research & Genetic Epidemiology, St Thomas Hospital, King's College London, London, UK
| | - Cyrus Cooper
- MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton, UK
| | - Christopher G Bell
- William Harvey Research Institute, Barts & The London School of Medicine and Dentistry, Charterhouse Square, Queen Mary University of London, London, UK.
| |
Collapse
|
27
|
Ehrlich R, Davyt M, López I, Chalar C, Marín M. On the Track of the Missing tRNA Genes: A Source of Non-Canonical Functions? Front Mol Biosci 2021; 8:643701. [PMID: 33796548 PMCID: PMC8007984 DOI: 10.3389/fmolb.2021.643701] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 02/02/2021] [Indexed: 01/31/2023] Open
Abstract
Cellular tRNAs appear today as a diverse population of informative macromolecules with conserved general elements ensuring essential common functions and different and distinctive features securing specific interactions and activities. Their differential expression and the variety of post-transcriptional modifications they are subject to, lead to the existence of complex repertoires of tRNA populations adjusted to defined cellular states. Despite the tRNA-coding genes redundancy in prokaryote and eukaryote genomes, it is surprising to note the absence of genes coding specific translational-active isoacceptors throughout the phylogeny. Through the analysis of different releases of tRNA databases, this review aims to provide a general summary about those “missing tRNA genes.” This absence refers to both tRNAs that are not encoded in the genome, as well as others that show critical sequence variations that would prevent their activity as canonical translation adaptor molecules. Notably, while a group of genes are universally missing, others are absent in particular kingdoms. Functional information available allows to hypothesize that the exclusion of isodecoding molecules would be linked to: 1) reduce ambiguities of signals that define the specificity of the interactions in which the tRNAs are involved; 2) ensure the adaptation of the translational apparatus to the cellular state; 3) divert particular tRNA variants from ribosomal protein synthesis to other cellular functions. This leads to consider the “missing tRNA genes” as a source of putative non-canonical tRNA functions and to broaden the concept of adapter molecules in ribosomal-dependent protein synthesis.
Collapse
Affiliation(s)
- Ricardo Ehrlich
- Biochemistry-Molecular Biology, Faculty of Science, Universidad de la República, Montevideo, Uruguay.,Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - Marcos Davyt
- Biochemistry-Molecular Biology, Faculty of Science, Universidad de la República, Montevideo, Uruguay
| | - Ignacio López
- Biochemistry-Molecular Biology, Faculty of Science, Universidad de la República, Montevideo, Uruguay
| | - Cora Chalar
- Biochemistry-Molecular Biology, Faculty of Science, Universidad de la República, Montevideo, Uruguay
| | - Mónica Marín
- Biochemistry-Molecular Biology, Faculty of Science, Universidad de la República, Montevideo, Uruguay
| |
Collapse
|
28
|
Liu Y, Yang Q, Zhao F. Synonymous but Not Silent: The Codon Usage Code for Gene Expression and Protein Folding. Annu Rev Biochem 2021; 90:375-401. [PMID: 33441035 DOI: 10.1146/annurev-biochem-071320-112701] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Codon usage bias, the preference for certain synonymous codons, is found in all genomes. Although synonymous mutations were previously thought to be silent, a large body of evidence has demonstrated that codon usage can play major roles in determining gene expression levels and protein structures. Codon usage influences translation elongation speed and regulates translation efficiency and accuracy. Adaptation of codon usage to tRNA expression determines the proteome landscape. In addition, codon usage biases result in nonuniform ribosome decoding rates on mRNAs, which in turn influence the cotranslational protein folding process that is critical for protein function in diverse biological processes. Conserved genome-wide correlations have also been found between codon usage and protein structures. Furthermore, codon usage is a major determinant of mRNA levels through translation-dependent effects on mRNA decay and translation-independent effects on transcriptional and posttranscriptional processes. Here, we discuss the multifaceted roles and mechanisms of codon usage in different gene regulatory processes.
Collapse
Affiliation(s)
- Yi Liu
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9040, USA;
| | - Qian Yang
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9040, USA;
| | - Fangzhou Zhao
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9040, USA;
| |
Collapse
|
29
|
Aharon-Hefetz N, Frumkin I, Mayshar Y, Dahan O, Pilpel Y, Rak R. Manipulation of the human tRNA pool reveals distinct tRNA sets that act in cellular proliferation or cell cycle arrest. eLife 2020; 9:e58461. [PMID: 33357381 PMCID: PMC7781600 DOI: 10.7554/elife.58461] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 12/18/2020] [Indexed: 12/12/2022] Open
Abstract
Different subsets of the tRNA pool in human cells are expressed in different cellular conditions. The 'proliferation-tRNAs' are induced upon normal and cancerous cell division, while the 'differentiation-tRNAs' are active in non-dividing, differentiated cells. Here we examine the essentiality of the various tRNAs upon cellular growth and arrest. We established a CRISPR-based editing procedure with sgRNAs that each target a tRNA family. We measured tRNA essentiality for cellular growth and found that most proliferation-tRNAs are essential compared to differentiation- tRNAs in rapidly growing cell lines. Yet in more slowly dividing lines, the differentiation-tRNAs were more essential. In addition, we measured the essentiality of each tRNA family upon response to cell cycle arresting signals. Here we detected a more complex behavior with both proliferation-tRNAs and differentiation tRNAs showing various levels of essentiality. These results provide the so-far most comprehensive functional characterization of human tRNAs with intricate roles in various cellular states.
Collapse
Affiliation(s)
- Noa Aharon-Hefetz
- Department of Molecular Genetics, Weizmann Institute of ScienceRehovotIsrael
| | - Idan Frumkin
- Department of Molecular Genetics, Weizmann Institute of ScienceRehovotIsrael
| | - Yoav Mayshar
- Department of Molecular Cell Biology, Weizmann Institute of ScienceRehovotIsrael
| | - Orna Dahan
- Department of Molecular Genetics, Weizmann Institute of ScienceRehovotIsrael
| | - Yitzhak Pilpel
- Department of Molecular Genetics, Weizmann Institute of ScienceRehovotIsrael
| | - Roni Rak
- Department of Molecular Genetics, Weizmann Institute of ScienceRehovotIsrael
| |
Collapse
|
30
|
Hummel G, Berr A, Graindorge S, Cognat V, Ubrig E, Pflieger D, Molinier J, Drouard L. Epigenetic silencing of clustered tRNA genes in Arabidopsis. Nucleic Acids Res 2020; 48:10297-10312. [PMID: 32941623 PMCID: PMC7544208 DOI: 10.1093/nar/gkaa766] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 07/21/2020] [Accepted: 09/03/2020] [Indexed: 12/12/2022] Open
Abstract
Beyond their key role in translation, cytosolic transfer RNAs (tRNAs) are involved in a wide range of other biological processes. Nuclear tRNA genes (tDNAs) are transcribed by the RNA polymerase III (RNAP III) and cis-elements, trans-factors as well as genomic features are known to influence their expression. In Arabidopsis, besides a predominant population of dispersed tDNAs spread along the 5 chromosomes, some clustered tDNAs have been identified. Here, we demonstrate that these tDNA clusters are transcriptionally silent and that pathways involved in the maintenance of DNA methylation play a predominant role in their repression. Moreover, we show that clustered tDNAs exhibit repressive chromatin features whilst their dispersed counterparts contain permissive euchromatic marks. This work demonstrates that both genomic and epigenomic contexts are key players in the regulation of tDNAs transcription. The conservation of most of these regulatory processes suggests that this pioneering work in Arabidopsis can provide new insights into the regulation of RNA Pol III transcription in other organisms, including vertebrates.
Collapse
Affiliation(s)
- Guillaume Hummel
- Institut de biologie moléculaire des plantes-CNRS, Université de Strasbourg, 12 rue du Général Zimmer, F-67084 Strasbourg, France
| | - Alexandre Berr
- Institut de biologie moléculaire des plantes-CNRS, Université de Strasbourg, 12 rue du Général Zimmer, F-67084 Strasbourg, France
| | - Stéfanie Graindorge
- Institut de biologie moléculaire des plantes-CNRS, Université de Strasbourg, 12 rue du Général Zimmer, F-67084 Strasbourg, France
| | - Valérie Cognat
- Institut de biologie moléculaire des plantes-CNRS, Université de Strasbourg, 12 rue du Général Zimmer, F-67084 Strasbourg, France
| | - Elodie Ubrig
- Institut de biologie moléculaire des plantes-CNRS, Université de Strasbourg, 12 rue du Général Zimmer, F-67084 Strasbourg, France
| | - David Pflieger
- Institut de biologie moléculaire des plantes-CNRS, Université de Strasbourg, 12 rue du Général Zimmer, F-67084 Strasbourg, France
| | - Jean Molinier
- Institut de biologie moléculaire des plantes-CNRS, Université de Strasbourg, 12 rue du Général Zimmer, F-67084 Strasbourg, France
| | - Laurence Drouard
- Institut de biologie moléculaire des plantes-CNRS, Université de Strasbourg, 12 rue du Général Zimmer, F-67084 Strasbourg, France
| |
Collapse
|
31
|
Does proteostasis get lost in translation? Implications for protein aggregation across the lifespan. Ageing Res Rev 2020; 62:101119. [PMID: 32603841 DOI: 10.1016/j.arr.2020.101119] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 06/05/2020] [Accepted: 06/17/2020] [Indexed: 02/06/2023]
Abstract
Protein aggregation is a phenomenon of major relevance in neurodegenerative and neuromuscular disorders, cataracts, diabetes and many other diseases. Research has unveiled that proteins also aggregate in multiple tissues during healthy aging yet, the biological and biomedical relevance of this apparently asymptomatic phenomenon remains to be understood. It is known that proteome homeostasis (proteostasis) is maintained by a balanced protein synthesis rate, high protein synthesis accuracy, efficient protein folding and continual tagging of damaged proteins for degradation, suggesting that protein aggregation during healthy aging may be associated with alterations in both protein synthesis and the proteostasis network (PN) pathways. In particular, dysregulation of protein synthesis and alterations in translation fidelity are hypothesized to lead to the production of misfolded proteins which could explain the occurrence of age-related protein aggregation. Nevertheless, some data on this topic is controversial and the biological mechanisms that lead to widespread protein aggregation remain to be elucidated. We review the recent literature about the age-related decline of proteostasis, highlighting the need to build an integrated view of protein synthesis rate, fidelity and quality control pathways in order to better understand the proteome alterations that occur during aging and in age-related diseases.
Collapse
|
32
|
Kapur M, Ganguly A, Nagy G, Adamson SI, Chuang JH, Frankel WN, Ackerman SL. Expression of the Neuronal tRNA n-Tr20 Regulates Synaptic Transmission and Seizure Susceptibility. Neuron 2020; 108:193-208.e9. [PMID: 32853550 DOI: 10.1016/j.neuron.2020.07.023] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 06/07/2020] [Accepted: 07/19/2020] [Indexed: 12/31/2022]
Abstract
The mammalian genome has hundreds of nuclear-encoded tRNAs, but the contribution of individual tRNA genes to cellular and organismal function remains unknown. Here, we demonstrate that mutations in a neuronally enriched arginine tRNA, n-Tr20, increased seizure threshold and altered synaptic transmission. n-Tr20 expression also modulated seizures caused by an epilepsy-linked mutation in Gabrg2, a gene encoding a GABAA receptor subunit. Loss of n-Tr20 altered translation initiation by activating the integrated stress response and suppressing mTOR signaling, the latter of which may contribute to altered neurotransmission in mutant mice. Deletion of a highly expressed isoleucine tRNA similarly altered these signaling pathways in the brain, suggesting that regulation of translation initiation is a conserved response to tRNA loss. Our data indicate that loss of a single member of a tRNA family results in multiple cellular phenotypes, highlighting the disease-causing potential of tRNA mutations.
Collapse
Affiliation(s)
- Mridu Kapur
- Howard Hughes Medical Institute, Department of Cellular and Molecular Medicine, Section of Neurobiology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Archan Ganguly
- Howard Hughes Medical Institute, Department of Cellular and Molecular Medicine, Section of Neurobiology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Gabor Nagy
- The Jackson Laboratory, Bar Harbor, ME 04609, USA
| | - Scott I Adamson
- The Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA; Department of Genetics and Genome Sciences, Institute for Systems Genomics, UConn Health, Farmington, CT 06030, USA
| | - Jeffrey H Chuang
- The Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA
| | - Wayne N Frankel
- Institute for Genomic Medicine, Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Susan L Ackerman
- Howard Hughes Medical Institute, Department of Cellular and Molecular Medicine, Section of Neurobiology, University of California, San Diego, La Jolla, CA 92093, USA.
| |
Collapse
|
33
|
Functions of paralogous RNA polymerase III subunits POLR3G and POLR3GL in mouse development. Proc Natl Acad Sci U S A 2020; 117:15702-15711. [PMID: 32576691 DOI: 10.1073/pnas.1922821117] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Mammalian cells contain two isoforms of RNA polymerase III (Pol III) that differ in only a single subunit, with POLR3G in one form (Pol IIIα) and the related POLR3GL in the other form (Pol IIIβ). Previous research indicates that POLR3G and POLR3GL are differentially expressed, with POLR3G expression being highly enriched in embryonic stem cells (ESCs) and tumor cells relative to the ubiquitously expressed POLR3GL. To date, the functional differences between these two subunits remain largely unexplored, especially in vivo. Here, we show that POLR3G and POLR3GL containing Pol III complexes bind the same target genes and assume the same functions both in vitro and in vivo and, to a significant degree, can compensate for each other in vivo. Notably, an observed defect in the differentiation ability of POLR3G knockout ESCs can be rescued by exogenous expression of POLR3GL. Moreover, whereas POLR3G knockout mice die at a very early embryonic stage, POLR3GL knockout mice complete embryonic development without noticeable defects but die at about 3 wk after birth with signs of both general growth defects and potential cerebellum-related neuronal defects. The different phenotypes of the knockout mice likely reflect differential expression levels of POLR3G and POLR3GL across developmental stages and between tissues and insufficient amounts of total Pol III in vivo.
Collapse
|
34
|
Gene-Specific Control of tRNA Expression by RNA Polymerase II. Mol Cell 2020; 78:765-778.e7. [PMID: 32298650 DOI: 10.1016/j.molcel.2020.03.023] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 02/12/2020] [Accepted: 03/13/2020] [Indexed: 12/20/2022]
Abstract
Increasing evidence suggests that tRNA levels are dynamically and specifically regulated in response to internal and external cues to modulate the cellular translational program. However, the molecular players and the mechanisms regulating the gene-specific expression of tRNAs are still unknown. Using an inducible auxin-degron system to rapidly deplete RPB1 (the largest subunit of RNA Pol II) in living cells, we identified Pol II as a direct gene-specific regulator of tRNA transcription. Our data suggest that Pol II transcription robustly interferes with Pol III function at specific tRNA genes. This activity was further found to be essential for MAF1-mediated repression of a large set of tRNA genes during serum starvation, indicating that repression of tRNA genes by Pol II is dynamically regulated. Hence, Pol II plays a direct and central role in the gene-specific regulation of tRNA expression.
Collapse
|
35
|
Kames J, Alexaki A, Holcomb DD, Santana-Quintero LV, Athey JC, Hamasaki-Katagiri N, Katneni U, Golikov A, Ibla JC, Bar H, Kimchi-Sarfaty C. TissueCoCoPUTs: Novel Human Tissue-Specific Codon and Codon-Pair Usage Tables Based on Differential Tissue Gene Expression. J Mol Biol 2020; 432:3369-3378. [PMID: 31982380 DOI: 10.1016/j.jmb.2020.01.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 12/19/2019] [Accepted: 01/08/2020] [Indexed: 02/05/2023]
Abstract
Protein expression in multicellular organisms varies widely across tissues. Codon usage in the transcriptome of each tissue is derived from genomic codon usage and the relative expression level of each gene. We created a comprehensive computational resource that houses tissue-specific codon, codon-pair, and dinucleotide usage data for 51 Homo sapiens tissues (TissueCoCoPUTs: https://hive.biochemistry.gwu.edu/review/tissue_codon), using transcriptome data from the Broad Institute Genotype-Tissue Expression (GTEx) portal. Distances between tissue-specific codon and codon-pair frequencies were used to generate a dendrogram based on the unique patterns of codon and codon-pair usage in each tissue that are clearly distinct from the genomic distribution. This novel resource may be useful in unraveling the relationship between codon usage and tRNA abundance, which could be critical in determining translation kinetics and efficiency across tissues. Areas of investigation such as biotherapeutic development, tissue-specific genetic engineering, and genetic disease prediction will greatly benefit from this resource.
Collapse
Affiliation(s)
- Jacob Kames
- Division of Plasma Protein Therapeutics, Office of Tissue and Advanced Therapies, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD, 20993, USA
| | - Aikaterini Alexaki
- Division of Plasma Protein Therapeutics, Office of Tissue and Advanced Therapies, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD, 20993, USA
| | - David D Holcomb
- Division of Plasma Protein Therapeutics, Office of Tissue and Advanced Therapies, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD, 20993, USA
| | - Luis V Santana-Quintero
- High Performance Integrated Environment, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD, 20993, USA
| | - John C Athey
- Division of Plasma Protein Therapeutics, Office of Tissue and Advanced Therapies, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD, 20993, USA
| | - Nobuko Hamasaki-Katagiri
- Division of Plasma Protein Therapeutics, Office of Tissue and Advanced Therapies, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD, 20993, USA
| | - Upendra Katneni
- Division of Plasma Protein Therapeutics, Office of Tissue and Advanced Therapies, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD, 20993, USA
| | - Anton Golikov
- High Performance Integrated Environment, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD, 20993, USA
| | - Juan C Ibla
- Department of Anesthesiology, Critical Care and Pain Medicine, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA
| | - Haim Bar
- Department of Statistics, University of Connecticut, Storrs, CT, 06268, USA
| | - Chava Kimchi-Sarfaty
- Division of Plasma Protein Therapeutics, Office of Tissue and Advanced Therapies, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD, 20993, USA.
| |
Collapse
|
36
|
He YU, Wang S, Yin X, Sun F, He B, Liu X. Comparison of Extracellular Proteins from Virulent and Avirulent Vibrio parahaemolyticus Strains To Identify Potential Virulence Factors. J Food Prot 2020; 83:155-162. [PMID: 31860395 DOI: 10.4315/0362-028x.jfp-19-188] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Vibrio parahaemolyticus is a leading seafood-borne pathogen that causes gastroenteritis, septicemia, and serious wound infections due to the actions of virulence-associated proteins. We compared the extracellular proteins of nonvirulent JHY20 and virulent ATCC 33847 V. parahaemolyticus reference strains. Eighteen extracellular proteins were identified from secretory profiles, and 11 (68.75%) of the 16 proteins in ATCC 33847 are associated with virulence and/or protection against adverse conditions: trigger factor, chaperone SurA, aspartate-semialdehyde dehydrogenase, 4-hydroxy-3-methylbut-2-en-1-yl diphosphate synthase, glutamate 5-kinase, alanine dehydrogenase, glyceraldehyde-3-phosphate dehydrogenase, outer membrane protein OmpV, ribosome-associated inhibitor A, chaperone protein Skp, and universal stress protein. Two nontoxic-related proteins, amino acid ABC transporter substrate-binding protein and an uncharacterized protein, were identified in JHY20. The results provide a theoretical basis for supporting safety risk assessment of aquatic foods, illuminate the pathogenic mechanisms of V. parahaemolyticus, and assist the identification of novel vaccine candidates for foodborne pathogens.
Collapse
Affiliation(s)
- Y U He
- College of Food (Biotechnology) Engineering.,Key Construction Laboratory of Food Resources Development and the Quality Safety, Xuzhou University of Technology, Jiangsu, Xuzhou 221018, People's Republic of China
| | - Shuai Wang
- College of Food (Biotechnology) Engineering.,Key Construction Laboratory of Food Resources Development and the Quality Safety, Xuzhou University of Technology, Jiangsu, Xuzhou 221018, People's Republic of China
| | | | - Fengjiao Sun
- Logistics & Security Department, Shanghai Civil Aviation College, Shanghai 201300, People's Republic of China
| | - Bin He
- Environment Monitoring Station, Zaozhuang Municipal Bureau of Ecology and Environment, Shandong 277100, People's Republic of China
| | - Xiao Liu
- Henan Key Laboratory of Cold Chain Food Quality and Safety Control, Zhengzhou University of Light Industry, Zhengzhou 450001, People's Republic of China
| |
Collapse
|
37
|
Kuo ME, Antonellis A. Ubiquitously Expressed Proteins and Restricted Phenotypes: Exploring Cell-Specific Sensitivities to Impaired tRNA Charging. Trends Genet 2019; 36:105-117. [PMID: 31839378 DOI: 10.1016/j.tig.2019.11.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 11/17/2019] [Accepted: 11/18/2019] [Indexed: 12/17/2022]
Abstract
Aminoacyl-tRNA synthetases (ARS) are ubiquitously expressed, essential enzymes that charge tRNA with cognate amino acids. Variants in genes encoding ARS enzymes lead to myriad human inherited diseases. First, missense alleles cause dominant peripheral neuropathy. Second, missense, nonsense, and frameshift alleles cause recessive multisystem disorders that differentially affect tissues depending on which ARS is mutated. A preponderance of evidence has shown that both phenotypic classes are associated with loss-of-function alleles, suggesting that tRNA charging plays a central role in disease pathogenesis. However, it is currently unclear how perturbation in the function of these ubiquitously expressed enzymes leads to tissue-specific or tissue-predominant phenotypes. Here, we review our current understanding of ARS-associated disease phenotypes and discuss potential explanations for the observed tissue specificity.
Collapse
Affiliation(s)
- Molly E Kuo
- Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, MI, USA; Medical Scientist Training Program, University of Michigan, Ann Arbor, MI, USA
| | - Anthony Antonellis
- Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, MI, USA; Department of Human Genetics, University of Michigan, Ann Arbor, MI, USA; Department of Neurology, University of Michigan, Ann Arbor, MI, USA.
| |
Collapse
|
38
|
Berg MD, Giguere DJ, Dron JS, Lant JT, Genereaux J, Liao C, Wang J, Robinson JF, Gloor GB, Hegele RA, O'Donoghue P, Brandl CJ. Targeted sequencing reveals expanded genetic diversity of human transfer RNAs. RNA Biol 2019; 16:1574-1585. [PMID: 31407949 PMCID: PMC6779403 DOI: 10.1080/15476286.2019.1646079] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Transfer RNAs are required to translate genetic information into proteins as well as regulate other cellular processes. Nucleotide changes in tRNAs can result in loss or gain of function that impact the composition and fidelity of the proteome. Despite links between tRNA variation and disease, the importance of cytoplasmic tRNA variation has been overlooked. Using a custom capture panel, we sequenced 605 human tRNA-encoding genes from 84 individuals. We developed a bioinformatic pipeline that allows more accurate tRNA read mapping and identifies multiple polymorphisms occurring within the same variant. Our analysis identified 522 unique tRNA-encoding sequences that differed from the reference genome from 84 individuals. Each individual had ~66 tRNA variants including nine variants found in less than 5% of our sample group. Variants were identified throughout the tRNA structure with 17% predicted to enhance function. Eighteen anticodon mutants were identified including potentially mistranslating tRNAs; e.g., a tRNASer that decodes Phe codons. Similar engineered tRNA variants were previously shown to inhibit cell growth, increase apoptosis and induce the unfolded protein response in mammalian cell cultures and chick embryos. Our analysis shows that human tRNA variation has been underestimated. We conclude that the large number of tRNA genes provides a buffer enabling the emergence of variants, some of which could contribute to disease.
Collapse
Affiliation(s)
- Matthew D Berg
- Department of Biochemistry, The University of Western Ontario , London , ON , Canada
| | - Daniel J Giguere
- Department of Biochemistry, The University of Western Ontario , London , ON , Canada
| | - Jacqueline S Dron
- Department of Biochemistry, The University of Western Ontario , London , ON , Canada.,Robarts Research Institute, The University of Western Ontario , London , ON , Canada
| | - Jeremy T Lant
- Department of Biochemistry, The University of Western Ontario , London , ON , Canada
| | - Julie Genereaux
- Department of Biochemistry, The University of Western Ontario , London , ON , Canada
| | - Calwing Liao
- Department of Biochemistry, The University of Western Ontario , London , ON , Canada.,Robarts Research Institute, The University of Western Ontario , London , ON , Canada
| | - Jian Wang
- Robarts Research Institute, The University of Western Ontario , London , ON , Canada
| | - John F Robinson
- Robarts Research Institute, The University of Western Ontario , London , ON , Canada
| | - Gregory B Gloor
- Department of Biochemistry, The University of Western Ontario , London , ON , Canada
| | - Robert A Hegele
- Department of Biochemistry, The University of Western Ontario , London , ON , Canada.,Robarts Research Institute, The University of Western Ontario , London , ON , Canada.,Department of Medicine, The University of Western Ontario , London , ON , Canada
| | - Patrick O'Donoghue
- Department of Biochemistry, The University of Western Ontario , London , ON , Canada.,Department of Chemistry, The University of Western Ontario , London , ON , Canada
| | - Christopher J Brandl
- Department of Biochemistry, The University of Western Ontario , London , ON , Canada
| |
Collapse
|
39
|
Torres AG. Enjoy the Silence: Nearly Half of Human tRNA Genes Are Silent. Bioinform Biol Insights 2019; 13:1177932219868454. [PMID: 31447549 PMCID: PMC6688141 DOI: 10.1177/1177932219868454] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 07/17/2019] [Indexed: 01/05/2023] Open
Abstract
Transfer RNAs (tRNAs) are key components of the translation machinery. They read codons on messenger RNAs (mRNAs) and deliver the appropriate amino acid to the ribosome for protein synthesis. The human genome encodes more than 500 tRNA genes but their individual contribution to the cellular tRNA pool is unclear. In recent years, novel methods were developed to improve the quantification of tRNA gene expression, most of which rely on next-generation sequencing such as small RNA-Seq applied to tRNAs (tRNA-Seq). In a previous study, we presented a bioinformatics strategy to analyse tRNA-Seq datasets that we named 'isodecoder-specific tRNA gene contribution profiling' (Iso-tRNA-CP). Using Iso-tRNA-CP, we showed that tRNA gene expression is cell type- and tissue-specific and that this process can regulate tRNA-derived fragments abundance. An additional observation that stems from that work is that approximately half of human tRNA genes appeared silent or poorly expressed. In this commentary, I discuss this finding in light of the current literature and speculate on potential functions that transcriptionally silent tRNA genes may play. Studying silent tRNA genes may offer a unique opportunity to unravel novel mechanisms of cell regulation associated to tRNA biology.
Collapse
Affiliation(s)
- Adrian Gabriel Torres
- Institute for Research in Biomedicine, Barcelona Institute of Science and Technology, Barcelona, Spain
| |
Collapse
|
40
|
Hummel G, Warren J, Drouard L. The multi-faceted regulation of nuclear tRNA gene transcription. IUBMB Life 2019; 71:1099-1108. [PMID: 31241827 DOI: 10.1002/iub.2097] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 05/16/2019] [Indexed: 12/31/2022]
Abstract
Transfer RNAs are among the most ancient molecules of life on earth. Beyond their crucial role in protein synthesis as carriers of amino acids, they are also important players in a plethora of other biological processes. Many debates in term of biogenesis, regulation and function persist around these fascinating non-coding RNAs. Our review focuses on the first step of their biogenesis in eukaryotes, i.e. their transcription from nuclear genes. Numerous and complementary ways have emerged during evolution to regulate transfer RNA gene transcription. Here, we will summarize the different actors implicated in this process: cis-elements, trans-factors, genomic contexts, epigenetic environments and finally three-dimensional organization of nuclear genomes. © 2019 IUBMB Life, 2019 © 2019 IUBMB Life, 71(8):1099-1108, 2019.
Collapse
Affiliation(s)
- Guillaume Hummel
- Institut de biologie moléculaire des plantes-CNRS, Université de Strasbourg, 12 rue du Général Zimmer, F-67084 Strasbourg, France
| | - Jessica Warren
- Department of biology, Colorado State University, Fort Collins, Colorado, 80523, USA
| | - Laurence Drouard
- Institut de biologie moléculaire des plantes-CNRS, Université de Strasbourg, 12 rue du Général Zimmer, F-67084 Strasbourg, France
| |
Collapse
|
41
|
Lai RW, Lu R, Danthi PS, Bravo JI, Goumba A, Sampathkumar NK, Benayoun BA. Multi-level remodeling of transcriptional landscapes in aging and longevity. BMB Rep 2019. [PMID: 30526773 PMCID: PMC6386224 DOI: 10.5483/bmbrep.2019.52.1.296] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
In multi-cellular organisms, the control of gene expression is key not only for development, but also for adult cellular homeostasis, and gene expression has been observed to be deregulated with aging. In this review, we discuss the current knowledge on the transcriptional alterations that have been described to occur with age in metazoans. First, we discuss age-related transcriptional changes in protein-coding genes, the expected functional impact of such changes, and how known pro-longevity interventions impact these changes. Second, we discuss the changes and impact of emerging aspects of transcription in aging, including age-related changes in splicing, lncRNAs and circRNAs. Third, we discuss the changes and potential impact of transcription of transposable elements with aging. Fourth, we highlight small ncRNAs and their potential impact on the regulation of aging phenotypes. Understanding the aging transcriptome will be key to identify important regulatory targets, and ultimately slow-down or reverse aging and extend healthy lifespan in humans.
Collapse
Affiliation(s)
- Rochelle W Lai
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089, USA
| | - Ryan Lu
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089, USA
| | - Prakroothi S Danthi
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089, USA
| | - Juan I Bravo
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089; Graduate program in the Biology of Aging, University of Southern California, Los Angeles, CA 90089, USA
| | - Alexandre Goumba
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089, USA
| | | | - Bérénice A Benayoun
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089; USC Norris Comprehensive Cancer Center, Epigenetics and Gene Regulation, Los Angeles, CA 90089; USC Stem Cell Initiative, Los Angeles, CA 90089, USA
| |
Collapse
|
42
|
Torres AG, Reina O, Stephan-Otto Attolini C, Ribas de Pouplana L. Differential expression of human tRNA genes drives the abundance of tRNA-derived fragments. Proc Natl Acad Sci U S A 2019; 116:8451-8456. [PMID: 30962382 PMCID: PMC6486751 DOI: 10.1073/pnas.1821120116] [Citation(s) in RCA: 116] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The human genome encodes hundreds of transfer RNA (tRNA) genes but their individual contribution to the tRNA pool is not fully understood. Deep sequencing of tRNA transcripts (tRNA-Seq) can estimate tRNA abundance at single gene resolution, but tRNA structures and posttranscriptional modifications impair these analyses. Here we present a bioinformatics strategy to investigate differential tRNA gene expression and use it to compare tRNA-Seq datasets from cultured human cells and human brain. We find that sequencing caveats affect quantitation of only a subset of human tRNA genes. Unexpectedly, we detect several cases where the differences in tRNA expression among samples do not involve variations at the level of isoacceptor tRNA sets (tRNAs charged with the same amino acid but using different anticodons), but rather among tRNA genes within the same isodecoder set (tRNAs having the same anticodon sequence). Because isodecoder tRNAs are functionally equal in terms of genetic translation, their differential expression may be related to noncanonical tRNA functions. We show that several instances of differential tRNA gene expression result in changes in the abundance of tRNA-derived fragments (tRFs) but not of mature tRNAs. Examples of differentially expressed tRFs include PIWI-associated RNAs, tRFs present in tissue samples but not in cells cultured in vitro, and somatic tissue-specific tRFs. Our data support that differential expression of tRNA genes regulate noncanonical tRNA functions performed by tRFs.
Collapse
Affiliation(s)
- Adrian Gabriel Torres
- Institute for Research in Biomedicine, Barcelona Institute of Science and Technology, 08028 Barcelona, Catalonia, Spain
| | - Oscar Reina
- Institute for Research in Biomedicine, Barcelona Institute of Science and Technology, 08028 Barcelona, Catalonia, Spain
| | - Camille Stephan-Otto Attolini
- Institute for Research in Biomedicine, Barcelona Institute of Science and Technology, 08028 Barcelona, Catalonia, Spain
| | - Lluís Ribas de Pouplana
- Institute for Research in Biomedicine, Barcelona Institute of Science and Technology, 08028 Barcelona, Catalonia, Spain;
- Catalan Institution for Research and Advanced Studies, 08010 Barcelona, Catalonia, Spain
| |
Collapse
|
43
|
Biasoli D, Compston-Garnett L, Ricketts SL, Birand Z, Courtay-Cahen C, Fineberg E, Arendt M, Boerkamp K, Melin M, Koltookian M, Murphy S, Rutteman G, Lindblad-Toh K, Starkey M. A synonymous germline variant in a gene encoding a cell adhesion molecule is associated with cutaneous mast cell tumour development in Labrador and Golden Retrievers. PLoS Genet 2019; 15:e1007967. [PMID: 30901340 PMCID: PMC6447235 DOI: 10.1371/journal.pgen.1007967] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 04/03/2019] [Accepted: 01/16/2019] [Indexed: 02/06/2023] Open
Abstract
Mast cell tumours are the most common type of skin cancer in dogs, representing a significant concern in canine health. The molecular pathogenesis is largely unknown, but breed-predisposition for mast cell tumour development suggests the involvement of inherited genetic risk factors in some breeds. In this study, we aimed to identify germline risk factors associated with the development of mast cell tumours in Labrador Retrievers, a breed with an elevated risk of mast cell tumour development. Using a methodological approach that combined a genome-wide association study, targeted next generation sequencing, and TaqMan genotyping, we identified a synonymous variant in the DSCAM gene on canine chromosome 31 that is associated with mast cell tumours in Labrador Retrievers. DSCAM encodes a cell-adhesion molecule. We showed that the variant has no effect on the DSCAM mRNA level but is associated with a significant reduction in the level of the DSCAM protein, suggesting that the variant affects the dynamics of DSCAM mRNA translation. Furthermore, we showed that the variant is also associated with mast cell tumours in Golden Retrievers, a breed that is closely related to Labrador Retrievers and that also has a predilection for mast cell tumour development. The variant is common in both Labradors and Golden Retrievers and consequently is likely to be a significant genetic contributor to the increased susceptibility of both breeds to develop mast cell tumours. The results presented here not only represent an important contribution to the understanding of mast cell tumour development in dogs, as they highlight the role of cell adhesion in mast cell tumour tumourigenesis, but they also emphasise the potential importance of the effects of synonymous variants in complex diseases such as cancer. The combination of various genetic and environmental risk factors makes the understanding of the molecular circuitry behind complex diseases, like cancer, a major challenge. The homogeneous nature of pedigree dog breed genomes makes these dogs ideal for the identification of both simple disease-causing genetic variants and genetic risk factors for complex diseases. Mast cell tumours are the most common type of canine skin cancer, and one of the most common cancers affecting dogs of most breeds. Several breeds, including Labrador Retrievers (which represent one of the most popular dog breeds), have an elevated risk of mast cell tumour development. Here, by using a methodological approach that combined different techniques, we identified a common inherited synonymous variant, that predisposes Labrador Retrievers to mast cell tumour development. Interestingly, we showed that this variant, despite its synonymous nature, appears to have an effect on translation dynamics as it is associated with reduced levels of DSCAM, a cell adhesion molecule. The results presented here reveal dysregulation of cell adhesion to be an important factor in mast cell tumour pathogenesis, and also highlight the important role that synonymous variants can play in complex diseases.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Maja Arendt
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Kim Boerkamp
- Department of Clinical Sciences of Companion Animals, Utrecht University, Utrecht, The Netherlands
| | - Malin Melin
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Michele Koltookian
- Broad Institute of MIT and Harvard, Cambridge, MA, United States of America
| | - Sue Murphy
- Animal Health Trust, Newmarket, United Kingdom
| | - Gerard Rutteman
- Department of Clinical Sciences of Companion Animals, Utrecht University, Utrecht, The Netherlands
- Veterinary Specialist Centre De Wagenrenk, Wageningen, The Netherlands
| | - Kerstin Lindblad-Toh
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
- Broad Institute of MIT and Harvard, Cambridge, MA, United States of America
| | - Mike Starkey
- Animal Health Trust, Newmarket, United Kingdom
- * E-mail:
| |
Collapse
|
44
|
Boivin V, Faucher-Giguère L, Scott M, Abou-Elela S. The cellular landscape of mid-size noncoding RNA. WILEY INTERDISCIPLINARY REVIEWS-RNA 2019; 10:e1530. [PMID: 30843375 PMCID: PMC6619189 DOI: 10.1002/wrna.1530] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 02/08/2019] [Accepted: 02/09/2019] [Indexed: 01/06/2023]
Abstract
Noncoding RNA plays an important role in all aspects of the cellular life cycle, from the very basic process of protein synthesis to specialized roles in cell development and differentiation. However, many noncoding RNAs remain uncharacterized and the function of most of them remains unknown. Mid-size noncoding RNAs (mncRNAs), which range in length from 50 to 400 nucleotides, have diverse regulatory functions but share many fundamental characteristics. Most mncRNAs are produced from independent promoters although others are produced from the introns of other genes. Many are found in multiple copies in genomes. mncRNAs are highly structured and carry many posttranscriptional modifications. Both of these facets dictate their RNA-binding protein partners and ultimately their function. mncRNAs have already been implicated in translation, catalysis, as guides for RNA modification, as spliceosome components and regulatory RNA. However, recent studies are adding new mncRNA functions including regulation of gene expression and alternative splicing. In this review, we describe the different classes, characteristics and emerging functions of mncRNAs and their relative expression patterns. Finally, we provide a portrait of the challenges facing their detection and annotation in databases. This article is categorized under: Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAs RNA Structure and Dynamics > RNA Structure, Dynamics, and Chemistry RNA Structure and Dynamics > Influence of RNA Structure in Biological Systems RNA Evolution and Genomics > RNA and Ribonucleoprotein Evolution.
Collapse
Affiliation(s)
- Vincent Boivin
- Department of Biochemistry, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Laurence Faucher-Giguère
- Department of Microbiology and Infectious Disease, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Michelle Scott
- Department of Biochemistry, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Sherif Abou-Elela
- Department of Microbiology and Infectious Disease, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| |
Collapse
|
45
|
Stein KC, Frydman J. The stop-and-go traffic regulating protein biogenesis: How translation kinetics controls proteostasis. J Biol Chem 2018; 294:2076-2084. [PMID: 30504455 DOI: 10.1074/jbc.rev118.002814] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Generating a functional proteome requires the ribosome to carefully regulate disparate co-translational processes that determine the fate of nascent polypeptides. With protein synthesis being energetically expensive, the ribosome must balance the costs of efficiently making a protein with those of properly folding it. Emerging as a primary means of regulating this trade-off is the nonuniform rate of translation elongation that defines translation kinetics. The varying speeds with which the ribosome progresses along a transcript have been implicated in several aspects of protein biogenesis, including co-translational protein folding and translational fidelity, as well as gene expression by mediating mRNA decay and protein quality control pathways. The optimal translation kinetics required to efficiently execute these processes can be distinct. Thus, the ribosome is tasked with tightly regulating translation kinetics to balance these processes while maintaining adaptability for changing cellular conditions. In this review, we first discuss the regulatory role of translation elongation in protein biogenesis and what factors influence elongation kinetics. We then describe how changes in translation kinetics signal downstream pathways that dictate the fate of nascent polypeptides. By regulating these pathways, the kinetics of translation elongation has emerged as a critical tool for driving gene expression and maintaining proteostasis through varied mechanisms, including nascent chain folding and binding different ribosome-associated machinery. Indeed, a growing number of examples demonstrate the important role of local changes in elongation kinetics in modulating the pathophysiology of human disease.
Collapse
Affiliation(s)
| | - Judith Frydman
- From the Departments of Biology and .,Genetics, Stanford University, Stanford, California 94305
| |
Collapse
|
46
|
Abstract
The pool of transfer RNA (tRNA) molecules in cells allows the ribosome to decode genetic information. This repertoire of molecular decoders is positioned in the crossroad of the genome, the transcriptome, and the proteome. Omics and systems biology now allow scientists to explore the entire repertoire of tRNAs of many organisms, revealing basic exciting biology. The tRNA gene set of hundreds of species is now characterized, in addition to the tRNA genes of organelles and viruses. Genes encoding tRNAs for certain anticodon types appear in dozens of copies in a genome, while others are universally absent from any genome. Transcriptome measurement of tRNAs is challenging, but in recent years new technologies have allowed researchers to determine the dynamic expression patterns of tRNAs. These advances reveal that availability of ready-to-translate tRNA molecules is highly controlled by several transcriptional and posttranscriptional regulatory processes. This regulation shapes the proteome according to the cellular state. The tRNA pool profoundly impacts many aspects of cellular and organismal life, including protein expression level, translation accuracy, adequacy of folding, and even mRNA stability. As a result, the shape of the tRNA pool affects organismal health and may participate in causing conditions such as cancer and neurological conditions.
Collapse
Affiliation(s)
- Roni Rak
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, 76100 Israel;
| | - Orna Dahan
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, 76100 Israel;
| | - Yitzhak Pilpel
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, 76100 Israel;
| |
Collapse
|
47
|
Martinez G. tRNAs as primers and inhibitors of retrotransposons. Mob Genet Elements 2017; 7:1-6. [PMID: 29201533 DOI: 10.1080/2159256x.2017.1393490] [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: 09/06/2017] [Accepted: 10/13/2017] [Indexed: 10/18/2022] Open
Abstract
The functional relationship between tRNAs and retrotransposons have been known for more than 35 years. tRNAs are used as primer molecules to guide the reverse transcription of retrotransposons. Recently, tRNAs have also emerge as important players in the postranscriptional regulation of retrotransposons by means of tRNA-derived small RNAs. This surprisingly new layer of regulation indicates that tRNAs are used both in the promotion and the suppression of the reverse transcription of retrotransposons indicating their primary role in the life cycle of LTR retrotransposons. This adds another level of translational control to tRNAs. Here we review the different known levels of interactions of tRNAs and retrotransposons and highlight the unknown parts of this interaction.
Collapse
Affiliation(s)
- German Martinez
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
| |
Collapse
|
48
|
Van Bortle K, Phanstiel DH, Snyder MP. Topological organization and dynamic regulation of human tRNA genes during macrophage differentiation. Genome Biol 2017; 18:180. [PMID: 28931413 PMCID: PMC5607496 DOI: 10.1186/s13059-017-1310-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 08/25/2017] [Indexed: 12/11/2022] Open
Abstract
Background The human genome is hierarchically organized into local and long-range structures that help shape cell-type-specific transcription patterns. Transfer RNA (tRNA) genes (tDNAs), which are transcribed by RNA polymerase III (RNAPIII) and encode RNA molecules responsible for translation, are dispersed throughout the genome and, in many cases, linearly organized into genomic clusters with other tDNAs. Whether the location and three-dimensional organization of tDNAs contribute to the activity of these genes has remained difficult to address, due in part to unique challenges related to tRNA sequencing. We therefore devised integrated tDNA expression profiling, a method that combines RNAPIII mapping with biotin-capture of nascent tRNAs. We apply this method to the study of dynamic tRNA gene regulation during macrophage development and further integrate these data with high-resolution maps of 3D chromatin structure. Results Integrated tDNA expression profiling reveals domain-level and loop-based organization of tRNA gene transcription during cellular differentiation. tRNA genes connected by DNA loops, which are proximal to CTCF binding sites and expressed at elevated levels compared to non-loop tDNAs, change coordinately with tDNAs and protein-coding genes at distal ends of interactions mapped by in situ Hi-C. We find that downregulated tRNA genes are specifically marked by enhanced promoter-proximal binding of MAF1, a transcriptional repressor of RNAPIII activity, altogether revealing multiple levels of tDNA regulation during cellular differentiation. Conclusions We present evidence of both local and coordinated long-range regulation of human tDNA expression, suggesting the location and organization of tRNA genes contribute to dynamic tDNA activity during macrophage development. Electronic supplementary material The online version of this article (doi:10.1186/s13059-017-1310-3) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Kevin Van Bortle
- Department of Genetics, Stanford University, Stanford, CA, 94305, USA
| | - Douglas H Phanstiel
- Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill, NC, 27599, USA.,Thurston Arthritis Research Center and Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Michael P Snyder
- Department of Genetics, Stanford University, Stanford, CA, 94305, USA.
| |
Collapse
|
49
|
Maraia RJ, Arimbasseri AG. Factors That Shape Eukaryotic tRNAomes: Processing, Modification and Anticodon-Codon Use. Biomolecules 2017; 7:biom7010026. [PMID: 28282871 PMCID: PMC5372738 DOI: 10.3390/biom7010026] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 02/24/2017] [Indexed: 01/24/2023] Open
Abstract
Transfer RNAs (tRNAs) contain sequence diversity beyond their anticodons and the large variety of nucleotide modifications found in all kingdoms of life. Some modifications stabilize structure and fit in the ribosome whereas those to the anticodon loop modulate messenger RNA (mRNA) decoding activity more directly. The identities of tRNAs with some universal anticodon loop modifications vary among distant and parallel species, likely to accommodate fine tuning for their translation systems. This plasticity in positions 34 (wobble) and 37 is reflected in codon use bias. Here, we review convergent evidence that suggest that expansion of the eukaryotic tRNAome was supported by its dedicated RNA polymerase III transcription system and coupling to the precursor-tRNA chaperone, La protein. We also review aspects of eukaryotic tRNAome evolution involving G34/A34 anticodon-sparing, relation to A34 modification to inosine, biased codon use and regulatory information in the redundancy (synonymous) component of the genetic code. We then review interdependent anticodon loop modifications involving position 37 in eukaryotes. This includes the eukaryote-specific tRNA modification, 3-methylcytidine-32 (m3C32) and the responsible gene, TRM140 and homologs which were duplicated and subspecialized for isoacceptor-specific substrates and dependence on i6A37 or t6A37. The genetics of tRNA function is relevant to health directly and as disease modifiers.
Collapse
Affiliation(s)
- Richard J Maraia
- Intramural Research Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892, USA.
- Commissioned Corps, U.S. Public Health Service, Rockville, MD, 20016, USA.
| | - Aneeshkumar G Arimbasseri
- Molecular Genetics Laboratory, National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi 110067, India.
| |
Collapse
|