1
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Roach AN, Bhadsavle SS, Higgins SL, Derrico DD, Basel A, Thomas KN, Golding MC. Alterations in sperm RNAs persist after alcohol cessation and correlate with epididymal mitochondrial dysfunction. Andrology 2024; 12:1012-1023. [PMID: 38044754 PMCID: PMC11144833 DOI: 10.1111/andr.13566] [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: 06/15/2023] [Revised: 10/10/2023] [Accepted: 11/20/2023] [Indexed: 12/05/2023]
Abstract
BACKGROUND Chronic preconception paternal alcohol use adversely modifies the sperm epigenome, inducing fetoplacental and craniofacial growth defects in the offspring of exposed males. A crucial outstanding question in the field of paternal epigenetic inheritance concerns the resilience of the male germline and its capacity to recover and correct sperm-inherited epigenetic errors after stressor withdrawal. OBJECTIVES We set out to determine if measures of the sperm-inherited epigenetic program revert to match the control treatment 1 month after withdrawing the daily alcohol treatments. MATERIALS AND METHODS Using a voluntary access model, we exposed C57BL/6J males to 6% or 10% alcohol for 10 weeks, withdrew the alcohol treatments for 4 weeks, and used RNA sequencing to examine gene expression patterns in the caput section of the epididymis. We then compared the abundance of sperm small RNA species between treatments. RESULTS In the caput section of the epididymis, chronic alcohol exposure induced changes in the transcriptional control of genetic pathways related to the mitochondrial function, oxidative phosphorylation, and the generalized stress response (EIF2 signaling). Subsequent analysis identified region-specific, alcohol-induced changes in mitochondrial DNA copy number across the epididymis, which correlated with increases in the mitochondrial DNA content of alcohol-exposed sperm. Notably, in the corpus section of the epididymis, increases in mitochondrial DNA copy number persisted 1 month after alcohol cessation. Analysis of sperm noncoding RNAs between control and alcohol-exposed males 1 month after alcohol withdrawal revealed a ∼100-fold increase in mir-196a, a microRNA induced as part of the nuclear factor erythroid 2-related factor 2 (Nrf2)-driven cellular antioxidant response. DISCUSSION AND CONCLUSION Our data reveal that alcohol-induced epididymal mitochondrial dysfunction and differences in sperm noncoding RNA content persist after alcohol withdrawal. Further, differences in mir-196a and sperm mitochondrial DNA copy number may serve as viable biomarkers of adverse alterations in the sperm-inherited epigenetic program.
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Affiliation(s)
- Alexis N. Roach
- Department of Veterinary Physiology & Pharmacology, School of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA, 77843
| | - Sanat S. Bhadsavle
- Department of Veterinary Physiology & Pharmacology, School of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA, 77843
| | - Samantha L. Higgins
- Department of Veterinary Physiology & Pharmacology, School of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA, 77843
| | - Destani D. Derrico
- Department of Veterinary Physiology & Pharmacology, School of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA, 77843
| | - Alison Basel
- Department of Veterinary Physiology & Pharmacology, School of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA, 77843
| | - Kara N. Thomas
- Department of Veterinary Physiology & Pharmacology, School of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA, 77843
| | - Michael C. Golding
- Department of Veterinary Physiology & Pharmacology, School of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA, 77843
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2
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Pinzaru AM, Tavazoie SF. Transfer RNAs as dynamic and critical regulators of cancer progression. Nat Rev Cancer 2023; 23:746-761. [PMID: 37814109 DOI: 10.1038/s41568-023-00611-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/28/2023] [Indexed: 10/11/2023]
Abstract
Transfer RNAs (tRNAs) have been historically viewed as non-dynamic adaptors that decode the genetic code into proteins. Recent work has uncovered dynamic regulatory roles for these fascinating molecules. Advances in tRNA detection methods have revealed that specific tRNAs can become modulated upon DNA copy number and chromatin alterations and can also be perturbed by oncogenic signalling and transcriptional regulators in cancer cells or the tumour microenvironment. Such alterations in the levels of specific tRNAs have been shown to causally impact cancer progression, including metastasis. Moreover, sequencing methods have identified tRNA-derived small RNAs that influence various aspects of cancer progression, such as cell proliferation and invasion, and could serve as diagnostic and prognostic biomarkers or putative therapeutic targets in various cancers. Finally, there is accumulating evidence, including from genetic models, that specific tRNA synthetases - the enzymes responsible for charging tRNAs with amino acids - can either promote or suppress tumour formation. In this Review, we provide an overview of how deregulation of tRNAs influences cancer formation and progression.
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Affiliation(s)
- Alexandra M Pinzaru
- Laboratory of Systems Cancer Biology, The Rockefeller University, New York, NY, USA.
| | - Sohail F Tavazoie
- Laboratory of Systems Cancer Biology, The Rockefeller University, New York, NY, USA.
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3
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Liu Z, Wang J, Shi Y, Yee BA, Terrey M, Zhang Q, Lee JC, Lin KI, Wang AHJ, Ackerman S, Yeo G, Cui H, Yang XL. Seryl-tRNA synthetase promotes translational readthrough by mRNA binding and involvement of the selenocysteine incorporation machinery. Nucleic Acids Res 2023; 51:10768-10781. [PMID: 37739431 PMCID: PMC10602924 DOI: 10.1093/nar/gkad773] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 08/17/2023] [Accepted: 09/19/2023] [Indexed: 09/24/2023] Open
Abstract
Translational readthrough of UGA stop codons by selenocysteine-specific tRNA (tRNASec) enables the synthesis of selenoproteins. Seryl-tRNA synthetase (SerRS) charges tRNASec with serine, which is modified into selenocysteine and delivered to the ribosome by a designated elongation factor (eEFSec in eukaryotes). Here we found that components of the human selenocysteine incorporation machinery (SerRS, tRNASec, and eEFSec) also increased translational readthrough of non-selenocysteine genes, including VEGFA, to create C-terminally extended isoforms. SerRS recognizes target mRNAs through a stem-loop structure that resembles the variable loop of its cognate tRNAs. This function of SerRS depends on both its enzymatic activity and a vertebrate-specific domain. Through eCLIP-seq, we identified additional SerRS-interacting mRNAs as potential readthrough genes. Moreover, SerRS overexpression was sufficient to reverse premature termination caused by a pathogenic nonsense mutation. Our findings expand the repertoire of selenoprotein biosynthesis machinery and suggest an avenue for therapeutic targeting of nonsense mutations using endogenous factors.
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Affiliation(s)
- Ze Liu
- Department of Molecular Medicine, Scripps Research Institute, La Jolla, CA 92037, USA
| | - Justin Wang
- Department of Molecular Medicine, Scripps Research Institute, La Jolla, CA 92037, USA
| | - Yi Shi
- Department of Molecular Medicine, Scripps Research Institute, La Jolla, CA 92037, USA
- Department of Biochemistry, School of Medicine, Nankai University, Tianjin, China
| | - Brian A Yee
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA 92093, USA
| | - Markus Terrey
- Howard Hughes Medical Institute, Department of Cellular and Molecular Medicine, School of Medicine, University of California San Diego, La Jolla, CA 92093, USA
| | - Qian Zhang
- Department of Molecular Medicine, Scripps Research Institute, La Jolla, CA 92037, USA
| | - Jenq-Chang Lee
- Department of Surgery, National Cheng Kung University Medical College and Hospital, Taiwan
| | - Kuo-I Lin
- Genomics Research Center, Academia Sinica, Taiwan
| | - Andrew H-J Wang
- The Ph.D. Program for Translational Medicine, College of Medical Science and Technology, Taipei Medical University and Academia Sinica, Taipei 110, Taiwan
| | - Susan L Ackerman
- Howard Hughes Medical Institute, Department of Cellular and Molecular Medicine, School of Medicine, University of California San Diego, La Jolla, CA 92093, USA
- Department of Neurobiology, University of California San Diego, La Jolla, CA 92093, USA
| | - Gene W Yeo
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA 92093, USA
| | - Haissi Cui
- Department of Molecular Medicine, Scripps Research Institute, La Jolla, CA 92037, USA
| | - Xiang-Lei Yang
- Department of Molecular Medicine, Scripps Research Institute, La Jolla, CA 92037, USA
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4
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Rouya C, Yambire KF, Derbyshire ML, Alwaseem H, Tavazoie SF. Inter-organellar nucleic acid communication by a mitochondrial tRNA regulates nuclear metabolic transcription. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.21.558912. [PMID: 37790361 PMCID: PMC10542527 DOI: 10.1101/2023.09.21.558912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
Efficient communication between mitochondria and the nucleus underlies homoeostatic metabolic control, though the involved mitochondrial factors and their mechanisms are poorly defined. Here, we report the surprising detection of multiple mitochondrial-derived transfer RNAs (mito-tRNAs) within the nuclei of human cells. Focused studies of nuclear-transported mito-tRNA-asparagine (mtAsn) revealed that its cognate charging enzyme (NARS2) is also present in the nucleus. MtAsn promoted interaction of NARS2 with histone deacetylase 2 (HDAC2), and repressed HDAC2 association with specific chromatin loci. Perturbation of this axis using antisense oligonucleotides promoted nucleotide biogenesis and enhanced breast cancer growth, and RNA and nascent transcript sequencing demonstrated specific alterations in the transcription of nuclear genes. These findings uncover nucleic-acid mediated communication between two organelles and the existence of a machinery for nuclear gene regulation by a mito-tRNA that restricts tumor growth through metabolic control. Highlights Multiple mitochondrial-derived tRNAs are detected in human cell nucleiMtAsn promotes binding between NARS2 and HDAC2Metabolic alterations driven by mtAsn impact cell proliferationMtAsn inhibition releases HDAC2 to bind and transcriptionally regulate multiple nuclear genes.
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5
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Tijaro-Bulla S, Nyandwi SP, Cui H. Physiological and engineered tRNA aminoacylation. WILEY INTERDISCIPLINARY REVIEWS. RNA 2023; 14:e1789. [PMID: 37042417 DOI: 10.1002/wrna.1789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 03/11/2023] [Accepted: 03/21/2023] [Indexed: 04/13/2023]
Abstract
Aminoacyl-tRNA synthetases form the protein family that controls the interpretation of the genetic code, with tRNA aminoacylation being the key chemical step during which an amino acid is assigned to a corresponding sequence of nucleic acids. In consequence, aminoacyl-tRNA synthetases have been studied in their physiological context, in disease states, and as tools for synthetic biology to enable the expansion of the genetic code. Here, we review the fundamentals of aminoacyl-tRNA synthetase biology and classification, with a focus on mammalian cytoplasmic enzymes. We compile evidence that the localization of aminoacyl-tRNA synthetases can be critical in health and disease. In addition, we discuss evidence from synthetic biology which made use of the importance of subcellular localization for efficient manipulation of the protein synthesis machinery. This article is categorized under: RNA Processing Translation > Translation Regulation RNA Processing > tRNA Processing RNA Export and Localization > RNA Localization.
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Affiliation(s)
| | | | - Haissi Cui
- Department of Chemistry, University of Toronto, Toronto, Ontario, Canada
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6
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Abstract
The study of eukaryotic tRNA processing has given rise to an explosion of new information and insights in the last several years. We now have unprecedented knowledge of each step in the tRNA processing pathway, revealing unexpected twists in biochemical pathways, multiple new connections with regulatory pathways, and numerous biological effects of defects in processing steps that have profound consequences throughout eukaryotes, leading to growth phenotypes in the yeast Saccharomyces cerevisiae and to neurological and other disorders in humans. This review highlights seminal new results within the pathways that comprise the life of a tRNA, from its birth after transcription until its death by decay. We focus on new findings and revelations in each step of the pathway including the end-processing and splicing steps, many of the numerous modifications throughout the main body and anticodon loop of tRNA that are so crucial for tRNA function, the intricate tRNA trafficking pathways, and the quality control decay pathways, as well as the biogenesis and biology of tRNA-derived fragments. We also describe the many interactions of these pathways with signaling and other pathways in the cell.
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Affiliation(s)
- Eric M Phizicky
- Department of Biochemistry and Biophysics and Center for RNA Biology, University of Rochester School of Medicine, Rochester, New York 14642, USA
| | - Anita K Hopper
- Department of Molecular Genetics and Center for RNA Biology, Ohio State University, Columbus, Ohio 43235, USA
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7
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Barros GC, Guerrero S, Silva GM. The central role of translation elongation in response to stress. Biochem Soc Trans 2023; 51:959-969. [PMID: 37318088 PMCID: PMC11160351 DOI: 10.1042/bst20220584] [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: 02/06/2023] [Revised: 06/02/2023] [Accepted: 06/05/2023] [Indexed: 06/16/2023]
Abstract
Protein synthesis is essential to support homeostasis, and thus, must be highly regulated during cellular response to harmful environments. All stages of translation are susceptible to regulation under stress, however, the mechanisms involved in translation regulation beyond initiation have only begun to be elucidated. Methodological advances enabled critical discoveries on the control of translation elongation, highlighting its important role in translation repression and the synthesis of stress-response proteins. In this article, we discuss recent findings on mechanisms of elongation control mediated by ribosome pausing and collisions and the availability of tRNAs and elongation factors. We also discuss how elongation intersects with distinct modes of translation control, further supporting cellular viability and gene expression reprogramming. Finally, we highlight how several of these pathways are reversibly regulated, emphasizing the dynamics of translation control during stress-response progression. A comprehensive understanding of translation regulation under stress will produce fundamental knowledge of protein dynamics while opening new avenues and strategies to overcome dysregulated protein production and cellular sensitivity to stress.
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Affiliation(s)
| | | | - Gustavo M. Silva
- Department of Biology, Duke University, Durham, NC, USA
- Lead contact
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8
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Jones JA, Wei N, Cui H, Shi Y, Fu G, Rauniyar N, Shapiro R, Morodomi Y, Berenst N, Dumitru CD, Kanaji S, Yates JR, Kanaji T, Yang XL. Nuclear translocation of an aminoacyl-tRNA synthetase may mediate a chronic "integrated stress response". Cell Rep 2023; 42:112632. [PMID: 37314928 PMCID: PMC10592355 DOI: 10.1016/j.celrep.2023.112632] [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: 06/07/2020] [Revised: 04/24/2023] [Accepted: 05/26/2023] [Indexed: 06/16/2023] Open
Abstract
Various stress conditions are signaled through phosphorylation of translation initiation factor eukaryotic initiation factor 2α (eIF2α) to inhibit global translation while selectively activating transcription factor ATF4 to aid cell survival and recovery. However, this integrated stress response is acute and cannot resolve lasting stress. Here, we report that tyrosyl-tRNA synthetase (TyrRS), a member of the aminoacyl-tRNA synthetase family that responds to diverse stress conditions through cytosol-nucleus translocation to activate stress-response genes, also inhibits global translation. However, it occurs at a later stage than eIF2α/ATF4 and mammalian target of rapamycin (mTOR) responses. Excluding TyrRS from the nucleus over-activates translation and increases apoptosis in cells under prolonged oxidative stress. Nuclear TyrRS transcriptionally represses translation genes by recruiting TRIM28 and/or NuRD complex. We propose that TyrRS, possibly along with other family members, can sense a variety of stress signals through intrinsic properties of this enzyme and strategically located nuclear localization signal and integrate them by nucleus translocation to effect protective responses against chronic stress.
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Affiliation(s)
- Julia A Jones
- Department of Molecular Medicine, Scripps Research Institute, La Jolla, CA 92037, USA
| | - Na Wei
- Department of Molecular Medicine, Scripps Research Institute, La Jolla, CA 92037, USA
| | - Haissi Cui
- Department of Molecular Medicine, Scripps Research Institute, La Jolla, CA 92037, USA
| | - Yi Shi
- Department of Molecular Medicine, Scripps Research Institute, La Jolla, CA 92037, USA
| | - Guangsen Fu
- Department of Molecular Medicine, Scripps Research Institute, La Jolla, CA 92037, USA
| | - Navin Rauniyar
- Department of Molecular Medicine, Scripps Research Institute, La Jolla, CA 92037, USA
| | - Ryan Shapiro
- Department of Molecular Medicine, Scripps Research Institute, La Jolla, CA 92037, USA
| | - Yosuke Morodomi
- Department of Molecular Medicine, Scripps Research Institute, La Jolla, CA 92037, USA
| | - Nadine Berenst
- Department of Molecular Medicine, Scripps Research Institute, La Jolla, CA 92037, USA
| | - Calin Dan Dumitru
- Department of Molecular Medicine, Scripps Research Institute, La Jolla, CA 92037, USA
| | - Sachiko Kanaji
- Department of Molecular Medicine, Scripps Research Institute, La Jolla, CA 92037, USA
| | - John R Yates
- Department of Molecular Medicine, Scripps Research Institute, La Jolla, CA 92037, USA
| | - Taisuke Kanaji
- Department of Molecular Medicine, Scripps Research Institute, La Jolla, CA 92037, USA
| | - Xiang-Lei Yang
- Department of Molecular Medicine, Scripps Research Institute, La Jolla, CA 92037, USA.
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9
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Zhu S, Wu Y, Zhang X, Peng S, Xiao H, Chen S, Xu L, Su T, Kuang M. Targeting N 7-methylguanosine tRNA modification blocks hepatocellular carcinoma metastasis after insufficient radiofrequency ablation. Mol Ther 2023; 31:1596-1614. [PMID: 35965412 PMCID: PMC10278047 DOI: 10.1016/j.ymthe.2022.08.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 06/10/2022] [Accepted: 08/09/2022] [Indexed: 11/17/2022] Open
Abstract
Radiofrequency heat ablation is an ideal radical treatment for hepatocellular carcinoma (HCC). However, insufficient radiofrequency ablation (IRFA) could lead to high recurrence of HCC. N7-methylguanosine (m7G) on tRNAs, an evolutionally conservative modification in mammals and yeast, modulates heat stress responses and tumor progression, while its function in HCC recurrence after IRFA remains unknown. Here, we found that IRFA significantly upregulates the level of m7G tRNA modification and its methyltransferase complex components METTL1/WDR4 in multiple systems including HCC patient-derived xenograft (PDX) mouse, patients' HCC tissues, sublethal-heat-treated models of HCC cell lines, and organoids. Functionally, gain-/loss-of-function assays showed that METTL1-mediated m7G tRNA modification promotes HCC metastasis under sublethal heat exposure both in vitro and in vivo. Mechanistically, we found that METTL1 and m7G tRNA modification enhance the translation of SLUG/SNAIL in a codon frequency-dependent manner under sublethal heat stress. Overexpression of SLUG/SNAIL rescued the malignant potency of METTL1 knockdown HCC cells after sublethal heat exposure. Our study uncovers the key functions of m7G tRNA modification in heat stress responses and HCC recurrence after IRFA, providing molecular basis for targeting METTL1-m7G-SLUG/SNAIL axis to prevent HCC metastasis after radiofrequency heat ablation treatment.
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Affiliation(s)
- Shenghua Zhu
- Department of Liver Surgery, Center of Hepato-Pancreato-Biliary Surgery, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China; Department of Gastroenterology and Hepatology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China; Institute of Precision Medicine, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China
| | - Yifan Wu
- Department of Gastroenterology and Hepatology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China; Institute of Precision Medicine, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China
| | - Xinyue Zhang
- Institute of Precision Medicine, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China; Department of Oncology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China
| | - Sui Peng
- Department of Gastroenterology and Hepatology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China; Institute of Precision Medicine, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China; Clinical Trials Unit, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China
| | - Han Xiao
- Division of Interventional Ultrasound, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China
| | - Shuling Chen
- Division of Interventional Ultrasound, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China
| | - Lixia Xu
- Institute of Precision Medicine, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China; Department of Oncology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China.
| | - Tianhong Su
- Institute of Precision Medicine, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China; Department of Oncology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China.
| | - Ming Kuang
- Department of Liver Surgery, Center of Hepato-Pancreato-Biliary Surgery, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China; Institute of Precision Medicine, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China; Cancer Center, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China.
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10
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Pan J, Liu Z, Shen B, Xu J, Dai G, Xu W, Wang J, Li L, Cheng L. tsRNA-04002 alleviates intervertebral disk degeneration by targeting PRKCA to inhibit apoptosis of nucleus pulposus cells. J Orthop Surg Res 2023; 18:413. [PMID: 37287061 PMCID: PMC10249188 DOI: 10.1186/s13018-023-03878-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 05/24/2023] [Indexed: 06/09/2023] Open
Abstract
BACKGROUND Intervertebral disk degeneration (IDD) is a degenerative disease that underlies various musculoskeletal and spinal disorders and is positively correlated with age. tRNA-derived small RNAs (tsRNA), as a new small noncoding RNAs, its function in IDD is unclear. Herein, our goal was to find the key tsRNA that affects IDD independently of age and explore the underlying mechanisms. METHODS Small RNA sequencing was performed in nucleus pulposus (NP) tissues of traumatic lumbar fracture individuals, young IDD (IDDY) patients, and old IDD (IDDO) patients. The biological functions of tsRNA-04002 in NP cells (NPCs) were investigated by qRT-PCR, western blot, and flow cytometry analysis. The molecular mechanism of tsRNA-04002 was demonstrated by luciferase assays and rescue experiments. Furthermore, the therapeutic effects of tsRNA-04002 on IDD rat model were used and evaluated in vivo. RESULTS Compared with fresh traumatic lumbar fracture patients, a total of 695 disordered tsRNAs is obtained (398 down-regulated tsRNAs and 297 up-regulated tsRNAs). These disordered tsRNAs were mainly involved in Wnt signaling pathway and MAPK signaling pathway. tsRNA-04002 was an age-independent key target in IDD, which was both lower expressed in IDDY and IDDO groups than control group. Overexpression of tsRNA-04002 restrained inflammatory cytokines IL-1β and TNF-α expression, increased the COL2A1, and inhibited the NPCs apoptosis. Furthermore, we determined that PRKCA was the target gene of tsRNA-04002 and was negatively regulated by tsRNA-04002. The rescue experiment results suggested that the high expression of PRKCA reversed the inhibitory effect of tsRNA-04002 mimics on NPCs inflammation and apoptosis, and promotive effect of COL2A1. Moreover, tsRNA-04002 treatment dramatically ameliorated the IDD process in the puncture-induced rat model, together with the blockade of PRKCA in vivo. CONCLUSION Collectively, our results substantiated that tsRNA-04002 could alleviate IDD by targeting PRKCA to inhibit apoptosis of NPCs. tsRNA-04002 may be a novel therapeutic target of IDD progression.
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Affiliation(s)
- Jie Pan
- Department of Spinal Surgery, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, 200092, China
| | - Zhonghan Liu
- Department of Spinal Surgery, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, 200092, China
| | - Bin Shen
- Department of Spinal Surgery, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, 200092, China
| | - Jin Xu
- Department of Anesthesiology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, 200092, China
| | - Gonghua Dai
- Department of Medical Imaging, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, 200092, China
| | - Wen Xu
- Department of Medical Imaging, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, 200092, China
| | - Jianjie Wang
- Department of Orthopedics, Tongji Hospital, School of Medicine, Tongji University, No.389 Xincun Road, Putuo Distrcit, Shanghai, 200092, China
| | - Lijun Li
- Department of Spinal Surgery, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, 200092, China.
| | - Liming Cheng
- Department of Orthopedics, Tongji Hospital, School of Medicine, Tongji University, No.389 Xincun Road, Putuo Distrcit, Shanghai, 200092, China.
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11
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Yu X, Tian AL, Wang P, Li J, Wu J, Li B, Liu Z, Liu S, Gao Z, Sun S, Sun S, Tu Y, Wu Q. Macrolide antibiotics activate the integrated stress response and promote tumor proliferation. Cell Stress 2023; 7:20-33. [PMID: 37021084 PMCID: PMC10069438 DOI: 10.15698/cst2023.04.278] [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: 02/12/2022] [Revised: 03/01/2023] [Accepted: 03/16/2023] [Indexed: 04/07/2023] Open
Abstract
Macrolide antibiotics are widely used antibacterial agents that are associated with autophagy inhibition. This study aimed to investigate the association between macrolide antibiotics and malignant tumors, as well as the effect on autophagy, reactive oxygen species (ROS) accumulation and integrated stress response (ISR). The meta-analysis indicated a modestly higher risk of cancer in macrolide antibiotic ever-users compared to non-users. Further experiments showed that macrolides block autophagic flux by inhibiting lysosomal acidification. Additionally, azithromycin, a representative macrolide antibiotic, induced the accumulation of ROS, and stimulated the ISR and the activation of transcription factor EB (TFEB) and TFE3 in a ROS-dependent manner. Finally, animal experiments confirmed that azithromycin promoted tumor progression in vivo, which could be receded by N-acetylcysteine, an inhibitor of ROS and ISR. Overall, this study reveals the potential role of macrolide antibiotics in malignant progression and highlights the need for further investigation into their effects.
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Affiliation(s)
- Xin Yu
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei, P. R. China
- # These authors have contributed equally to this work and share first authorship
| | - Ai-Ling Tian
- Gustave Roussy Cancer Campus, Villejuif Cedex, France
- Université Paris-Saclay, Faculté de Médecine, Le Kremlin-Bicêtre, France
- Centre de Recherche des Cordeliers, INSERM U1138, Équipe Labellisée - Ligue Nationale contre le Cancer, Université Paris Cité, Sorbonne Université, Paris, France
- Metabolomics and Cell Biology Platforms, Gustave Roussy Cancer Campus, Villejuif, France
- # These authors have contributed equally to this work and share first authorship
| | - Ping Wang
- Medical College, Anhui University of Science and Technology, Huainan, AnHui, P. R. China
- # These authors have contributed equally to this work and share first authorship
| | - Juanjuan Li
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei, P. R. China
| | - Juan Wu
- Department of Pathology, Renmin Hospital of Wuhan University, Wuhan, Hubei, P. R. China
| | - Bei Li
- Department of Pathology, Renmin Hospital of Wuhan University, Wuhan, Hubei, P. R. China
| | - Zhou Liu
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei, P. R. China
| | - Siqing Liu
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei, P. R. China
| | - Zhijie Gao
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei, P. R. China
| | - Si Sun
- Department of Clinical Laboratory, Renmin Hospital of Wuhan University, Wuhan, Hubei, P. R. China
| | - Shengrong Sun
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei, P. R. China
- * Corresponding Author: Dr. Shengrong Sun, Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, 238 Ziyang Road, Wuhan 430060, Hubei Province, P. R. China; E-mail:
| | - Yi Tu
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei, P. R. China
- * Corresponding Author: Dr. Yi Tu, Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, 238 Ziyang Road, Wuhan 430060, Hubei Province, P. R. China; E-mail:
| | - Qi Wu
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, P. R. China
- * Corresponding Author: Dr. Qi Wu, Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, P. R. China; E-mail:
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12
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U A, Viswam P, Kattupalli D, Eppurathu Vasudevan S. Elucidation of transfer RNAs as stress regulating agents and the experimental strategies to conceive the functional role of tRNA-derived fragments in plants. Crit Rev Biotechnol 2023; 43:275-292. [PMID: 35382663 DOI: 10.1080/07388551.2022.2026288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
In plants, the transfer RNAs (tRNAs) exhibit their profound influence in orchestrating diverse physiological activities like cell growth, development, and response to several surrounding stimuli. The tRNAs, which were known to restrict their function solely in deciphering the codons, are now emerging as frontline defenders in stress biology. The plants that are constantly confronted with a huge panoply of stresses rely on tRNA-mediated stress regulation by altering the tRNA abundance, curbing the transport of tRNAs, fragmenting the mature tRNAs during stress. Among them, the studies on the generation of transfer RNA-derived fragments (tRFs) and their biological implication in stress response have attained huge interest. In plants, the tRFs hold stable expression patterns and regulate biological functions under diverse environmental conditions. In this review, we discuss the fate of plant tRNAs upon stress and thereafter how the tRFs are metamorphosed into sharp ammunition to wrestle with stress. We also address the various methods developed to date for uncovering the role of tRFs and their function in plants.
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Affiliation(s)
- Aswathi U
- Rajiv Gandhi Centre for Biotechnology, Transdisciplinary Biology Laboratory, Thiruvananthapuram, India
| | - Pooja Viswam
- Rajiv Gandhi Centre for Biotechnology, Transdisciplinary Biology Laboratory, Thiruvananthapuram, India
| | - Divya Kattupalli
- Rajiv Gandhi Centre for Biotechnology, Transdisciplinary Biology Laboratory, Thiruvananthapuram, India
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13
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Lalpara JN, Hadiyal SD, Dhaduk BB, Gupta MK, Solanki MB, Sharon A, Dubal GG. Water Promoted One Pot Synthesis of Sesamol Derivatives as Potent Antioxidants: DFT, Molecular Docking, SAR and Single Crystal Studies. Polycycl Aromat Compd 2022. [DOI: 10.1080/10406638.2022.2083194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
| | | | - B. B. Dhaduk
- Department of Chemistry, Atmiya University, Rajkot, Gujarat, India
| | - Maneesh Kumar Gupta
- Department of Chemistry, Hotilal Ramnath College (A Constituent Unit of Jai Prakash University), Amnour, Chapra, Bihar, India
| | - M. B. Solanki
- School of Technology, Pandit Deendayal Petroleum University, Gandhinagar, India
| | | | - G. G. Dubal
- Department of Chemistry, RK University, Rajkot, Gujarat, India
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14
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Lee HK, Lee BR, Lee TJ, Lee CM, Li C, O'Connor PM, Dong Z, Kwon SH. Differential release of extracellular vesicle tRNA from oxidative stressed renal cells and ischemic kidneys. Sci Rep 2022; 12:1646. [PMID: 35102218 PMCID: PMC8803936 DOI: 10.1038/s41598-022-05648-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 01/14/2022] [Indexed: 11/09/2022] Open
Abstract
While urine-based liquid biopsy has expanded to the analyses of extracellular nucleic acids, the potential of transfer RNA (tRNA) encapsulated within extracellular vesicles has not been explored as a new class of urine biomarkers for kidney injury. Using rat kidney and mouse tubular cell injury models, we tested if extracellular vesicle-loaded tRNA and their m1A (N1-methyladenosine) modification reflect oxidative stress of kidney injury and determined the mechanism of tRNA packaging into extracellular vesicles. We determined a set of extracellular vesicle-loaded, isoaccepting tRNAs differentially released after ischemia-reperfusion injury and oxidative stress. Next, we found that m1A modification of extracellular vesicle tRNAs, despite an increase of the methylated tRNAs in intracellular vesicles, showed little or no change under oxidative stress. Mechanistically, oxidative stress decreases tRNA loading into intracellular vesicles while the tRNA-loaded vesicles are accumulated due to decreased release of the vesicles from the cell surface. Furthermore, Maf1-mediated transcriptional repression of the tRNAs decreases the cargo availability for extracellular vesicle release in response to oxidative stress. Taken together, our data support that release of extracellular vesicle tRNAs reflects oxidative stress of kidney tubules which might be useful to detect ischemic kidney injury and could lead to rebalance protein translation under oxidative stress.
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Affiliation(s)
- Hee Kyung Lee
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Byung Rho Lee
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Tae Jin Lee
- Center for Biotechnology and Genomic Medicine, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Chang Min Lee
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Chenglong Li
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Paul M O'Connor
- Department of Physiology, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Zheng Dong
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA
- Charlie Norwood VA Medical Center, Augusta, GA, USA
| | - Sang-Ho Kwon
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA.
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15
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Domínguez-López A, Magaña-Guerrero FS, Buentello-Volante B, Bautista-Hernández LA, Reyes-Grajeda JP, Bautista-de Lucio VM, Garfias Y. Amniotic membrane conditioned medium (AMCM) reduces inflammatory response on human limbal myofibroblast, and the potential role of lumican. Mol Vis 2021; 27:370-383. [PMID: 34447239 PMCID: PMC8370574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Accepted: 06/13/2021] [Indexed: 11/22/2022] Open
Abstract
PURPOSE Viral infections such as herpetic keratitis (HSK) activate the innate immune response in the cornea triggering opacity and loss of vision. This condition is performed mainly by myofibroblasts that exacerbate secretion of inflammatory cytokines. Amniotic membrane transplantation (AMT) reduces ocular opacity and scarring inhibiting secretion of inflammatory cytokines and proliferation of myofibroblasts. We previously reported that the amniotic membrane (AM) favors an anti-inflammatory microenvironment inhibiting the secretion of inflammatory cytokines, expression of innate immune receptors, and translocation of nuclear NF-κB on human limbal myofibroblasts (HLMs). The aim of the present study was to determine whether the soluble factors of the AM decrease the immune response of HLMs stimulated with polyinosinic-polycytidylic acid sodium salt (poly I:C). METHODS The AM was incubated in Dulbecco's modified eagle medium (DMEM)/F12, and the supernatant was collected to obtain amniotic membrane conditioned medium (AMCM). HLMs were isolated from cadaveric sclera-corneal rims. HLMs were cultured in DMEM/F12 or AMCM and stimulated or not with poly I:C (10 µg/ml) for 12 h to analyze synthesis of CCL2, CCL5, CXCL10, MDA5, RIG-1, and TLR3 or for 2 h to analyze translocation of nuclear NF-kB, IRF3, and IRF7. The proteins contained on AMCM were analyzed by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), and the acquired peptide ions were analyzed with the Mascot program using both National Center for Biotechnology Information (NCBI) and expressed sequence tag (EST) databases. RESULTS AMCM downregulated the mRNA levels of CCL2, CCL5, CXCL10, MDA5, RIG-1, and TLR3. In addition, AMCM decreased secretion of CCL2, CCL5, and CXCL10 and translocation of nuclear NF-κB. Interestingly, AMCM increased translocation of nuclear IRF3 and synthesis and secretion of type I IFN-β. We also identified small leucine-rich proteoglycan lumican in the AMCM. The administration of rh-lumican to poly I:C-stimulated HLMs reduced the mRNA levels of CCL2, CCL5, and CXCL10. CONCLUSIONS These results suggest that the AM can trigger an anti-inflammatory response on HLMs through soluble factors, and that lumican could play an important role in these effects.
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Affiliation(s)
- Alfredo Domínguez-López
- Research Unit, Institute of Ophthalmology Conde de Valenciana Foundation, Mexico City, Mexico,Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | | | | | | | | | | | - Yonathan Garfias
- Research Unit, Institute of Ophthalmology Conde de Valenciana Foundation, Mexico City, Mexico,Department of Biochemistry, Faculty of Medicine, Universidad Nacional Autónoma de México, Mexico City, Mexico
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16
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Rashad S, Tominaga T, Niizuma K. The cell and stress-specific canonical and noncanonical tRNA cleavage. J Cell Physiol 2021; 236:3710-3724. [PMID: 33043995 DOI: 10.1002/jcp.30107] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 09/30/2020] [Accepted: 10/03/2020] [Indexed: 12/18/2022]
Abstract
Following stress, transfer RNA (tRNA) is cleaved to generate tRNA halves (tiRNAs). These tiRNAs have been shown to repress protein translation. Angiogenin was considered the main enzyme that cleaves tRNA at its anticodon to generate 35-45 nucleotide long tiRNA halves, however, the recent reports indicate the presence of angiogenin-independent cleavage. We previously observed tRNA cleavage pattern occurring away from the anticodon site. To explore this noncanonical cleavage, we analyze tRNA cleavage patterns in rat model of ischemia-reperfusion and in two rat cell lines. In vivo mitochondrial tRNAs were prone to this noncanonical cleavage pattern. In vitro, however, cytosolic and mitochondrial tRNAs could be cleaved noncanonically. Our results show an important regulatory role of mitochondrial stress in angiogenin-mediated tRNA cleavage. Neither angiogenin nor RNH1 appear to regulate the noncanonical tRNA cleavage. Finally, we verified our previous findings of the role of Alkbh1 in regulating tRNA cleavage and its impact on noncanonical tRNA cleavage.
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Affiliation(s)
- Sherif Rashad
- Department of Neurosurgical Engineering and Translational Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan
- Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Teiji Tominaga
- Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Kuniyasu Niizuma
- Department of Neurosurgical Engineering and Translational Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan
- Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan
- Department of Neurosurgical Engineering and Translational Neuroscience, Graduate School of Biomedical Engineering, Tohoku University, Sendai, Japan
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17
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Abstract
Transfer RNAs play a key role in protein synthesis. Following transcription, tRNAs are extensively processed prior to their departure from the nucleus to become fully functional during translation. This includes removal of 5′ leaders and 3′ trailers by a specific endo- and/or exonuclease, 3′ CCA tail addition, posttranscriptional modifications and in some cases intron removal. In this minireview, the critical factors of nuclear tRNA trafficking are described based on studies in classical models such as yeast and human cell lines. In addition, recent findings and identification of novel regulatory loops of nuclear tRNA trafficking in trypanosomes are discussed with emphasis on tRNA modifications. The comparison between the representatives of opisthokonts and excavates serves here to understand the evolutionary conservation and diversity of nuclear tRNA export mechanisms.
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18
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Cristodero M, Brogli R, Joss O, Schimanski B, Schneider A, Polacek N. tRNA 3' shortening by LCCR4 as a response to stress in Trypanosoma brucei. Nucleic Acids Res 2021; 49:1647-1661. [PMID: 33406257 PMCID: PMC7897491 DOI: 10.1093/nar/gkaa1261] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 11/24/2020] [Accepted: 12/19/2020] [Indexed: 12/27/2022] Open
Abstract
Sensing of environmental cues is crucial for cell survival. To adapt to changes in their surroundings cells need to tightly control the repertoire of genes expressed at any time. Regulation of translation is key, especially in organisms in which transcription is hardly controlled, like Trypanosoma brucei. In this study, we describe the shortening of the bulk of the cellular tRNAs during stress at the expense of the conserved 3' CCA-tail. This tRNA shortening is specific for nutritional stress and renders tRNAs unsuitable substrates for translation. We uncovered the nuclease LCCR4 (Tb927.4.2430), a homologue of the conserved deadenylase Ccr4, as being responsible for tRNA trimming. Once optimal growth conditions are restored tRNAs are rapidly repaired by the trypanosome tRNA nucleotidyltransferase thus rendering the recycled tRNAs amenable for translation. This mechanism represents a fast and efficient way to repress translation during stress, allowing quick reactivation with a low energy input.
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Affiliation(s)
| | - Rebecca Brogli
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland
| | - Oliver Joss
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Bernd Schimanski
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - André Schneider
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Norbert Polacek
- Correspondence may also be addressed to Norbert Polacek. Tel: +41 031 631 4320;
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19
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Berg MD, Brandl CJ. Transfer RNAs: diversity in form and function. RNA Biol 2021; 18:316-339. [PMID: 32900285 PMCID: PMC7954030 DOI: 10.1080/15476286.2020.1809197] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 07/31/2020] [Accepted: 08/08/2020] [Indexed: 12/11/2022] Open
Abstract
As the adaptor that decodes mRNA sequence into protein, the basic aspects of tRNA structure and function are central to all studies of biology. Yet the complexities of their properties and cellular roles go beyond the view of tRNAs as static participants in protein synthesis. Detailed analyses through more than 60 years of study have revealed tRNAs to be a fascinatingly diverse group of molecules in form and function, impacting cell biology, physiology, disease and synthetic biology. This review analyzes tRNA structure, biosynthesis and function, and includes topics that demonstrate their diversity and growing importance.
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Affiliation(s)
- Matthew D. Berg
- Department of Biochemistry, The University of Western Ontario, London, Canada
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20
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Porat J, Kothe U, Bayfield MA. Revisiting tRNA chaperones: New players in an ancient game. RNA (NEW YORK, N.Y.) 2021; 27:rna.078428.120. [PMID: 33593999 PMCID: PMC8051267 DOI: 10.1261/rna.078428.120] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 02/10/2021] [Indexed: 05/03/2023]
Abstract
tRNAs undergo an extensive maturation process including post-transcriptional modifications that influence secondary and tertiary interactions. Precursor and mature tRNAs lacking key modifications are often recognized as aberrant and subsequently targeted for decay, illustrating the importance of modifications in promoting structural integrity. tRNAs also rely on tRNA chaperones to promote the folding of misfolded substrates into functional conformations. The best characterized tRNA chaperone is the La protein, which interacts with nascent RNA polymerase III transcripts to promote folding and offers protection from exonucleases. More recently, certain tRNA modification enzymes have also been demonstrated to possess tRNA folding activity distinct from their catalytic activity, suggesting that they may act as tRNA chaperones. In this review, we will discuss pioneering studies relating post-transcriptional modification to tRNA stability and decay pathways, present recent advances into the mechanism by which the RNA chaperone La assists pre-tRNA maturation, and summarize emerging research directions aimed at characterizing modification enzymes as tRNA chaperones. Together, these findings shed light on the importance of tRNA folding and how tRNA chaperones, in particular, increase the fraction of nascent pre-tRNAs that adopt a folded, functional conformation.
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21
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Avcilar-Kucukgoze I, Kashina A. Hijacking tRNAs From Translation: Regulatory Functions of tRNAs in Mammalian Cell Physiology. Front Mol Biosci 2020; 7:610617. [PMID: 33392265 PMCID: PMC7773854 DOI: 10.3389/fmolb.2020.610617] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Accepted: 11/10/2020] [Indexed: 12/12/2022] Open
Abstract
Transfer tRNAs (tRNAs) are small non-coding RNAs that are highly conserved in all kingdoms of life. Originally discovered as the molecules that deliver amino acids to the growing polypeptide chain during protein synthesis, tRNAs have been believed for a long time to play exclusive role in translation. However, recent studies have identified key roles for tRNAs and tRNA-derived small RNAs in multiple other processes, including regulation of transcription and translation, posttranslational modifications, stress response, and disease. These emerging roles suggest that tRNAs may be central players in the complex machinery of biological regulatory pathways. Here we overview these non-canonical roles of tRNA in normal physiology and disease, focusing largely on eukaryotic and mammalian systems.
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Affiliation(s)
- Irem Avcilar-Kucukgoze
- Department of Biomedical Sciences, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Anna Kashina
- Department of Biomedical Sciences, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, United States
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22
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Nostramo RT, Hopper AK. A novel assay provides insight into tRNAPhe retrograde nuclear import and re-export in S. cerevisiae. Nucleic Acids Res 2020; 48:11577-11588. [PMID: 33074312 PMCID: PMC7672469 DOI: 10.1093/nar/gkaa879] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 09/21/2020] [Accepted: 10/07/2020] [Indexed: 12/13/2022] Open
Abstract
In eukaryotes, tRNAs are transcribed in the nucleus and subsequently exported to the cytoplasm where they serve as essential adaptor molecules in translation. However, tRNAs can be returned to the nucleus by the evolutionarily conserved process called tRNA retrograde nuclear import, before relocalization back to the cytoplasm via a nuclear re-export step. Several important functions of these latter two trafficking events have been identified, yet the pathways are largely unknown. Therefore, we developed an assay in Saccharomyces cerevisiae to identify proteins mediating tRNA retrograde nuclear import and re-export using the unique wybutosine modification of mature tRNAPhe. Our hydrochloric acid/aniline assay revealed that the karyopherin Mtr10 mediates retrograde import of tRNAPhe, constitutively and in response to amino acid deprivation, whereas the Hsp70 protein Ssa2 mediates import specifically in the latter. Furthermore, tRNAPhe is re-exported by Crm1 and Mex67, but not by the canonical tRNA exporters Los1 or Msn5. These findings indicate that the re-export process occurs in a tRNA family-specific manner. Together, this assay provides insights into the pathways for tRNAPhe retrograde import and re-export and is a tool that can be used on a genome-wide level to identify additional gene products involved in these tRNA trafficking events.
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Affiliation(s)
- Regina T Nostramo
- Department of Molecular Genetics Center for RNA Biology The Ohio State University, Columbus, OH 43210, USA
| | - Anita K Hopper
- Department of Molecular Genetics Center for RNA Biology The Ohio State University, Columbus, OH 43210, USA
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23
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Vågbø CB, Slupphaug G. RNA in DNA repair. DNA Repair (Amst) 2020; 95:102927. [DOI: 10.1016/j.dnarep.2020.102927] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 07/07/2020] [Accepted: 07/08/2020] [Indexed: 12/22/2022]
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24
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Accornero F, Ross RL, Alfonzo JD. From canonical to modified nucleotides: balancing translation and metabolism. Crit Rev Biochem Mol Biol 2020; 55:525-540. [PMID: 32933330 DOI: 10.1080/10409238.2020.1818685] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Every type of nucleic acid in cells may undergo some kind of post-replicative or post-transcriptional chemical modification. Recent evidence has highlighted their importance in biology and their chemical complexity. In the following pages, we will describe new discoveries of modifications, with a focus on tRNA and mRNA. We will highlight current challenges and advances in modification detection and we will discuss how changes in nucleotide post-transcriptional modifications may affect cell homeostasis leading to malfunction. Although, RNA modifications prevail in all forms of life, the present review will focus on eukaryotic systems, where the great degree of intracellular compartmentalization provides barriers and filters for the level at which a given RNA is modified and will of course affect its fate and function. Additionally, although we will mention rRNA modification and modifications of the mRNA 5'-CAP structure, this will only be discussed in passing, as many substantive reviews have been written on these subjects. Here we will not spend much time describing all the possible modifications that have been observed; truly a daunting task. For reference, Bujnicki and coworkers have created MODOMICS, a useful repository for all types of modifications and their associated enzymes. Instead we will discuss a few examples, which illustrate our arguments on the connection of modifications, metabolism and ultimately translation. The fact remains, a full understanding of the long reach of nucleic acid modifications in cells requires both a global and targeted study of unprecedented scale, which at the moment may well be limited only by technology.
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Affiliation(s)
- Federica Accornero
- Department of Physiology and Cell Biology, The Ohio State University, Columbus, OH, USA.,The Center for RNA Biology, The Ohio State University, Columbus, OH, USA
| | - Robert L Ross
- Department of Chemistry, Rieveschl Laboratories for Mass Spectrometry, University of Cincinnati, Cincinnati, OH, USA
| | - Juan D Alfonzo
- The Center for RNA Biology, The Ohio State University, Columbus, OH, USA.,Department of Microbiology, The Ohio State University, Columbus, OH, USA
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25
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Rendezvous at Plasma Membrane: Cellular Lipids and tRNA Set up Sites of HIV-1 Particle Assembly and Incorporation of Host Transmembrane Proteins. Viruses 2020; 12:v12080842. [PMID: 32752131 PMCID: PMC7472227 DOI: 10.3390/v12080842] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 07/20/2020] [Accepted: 07/24/2020] [Indexed: 12/28/2022] Open
Abstract
The HIV-1 structural polyprotein Gag drives the virus particle assembly specifically at the plasma membrane (PM). During this process, the nascent virion incorporates specific subsets of cellular lipids and host membrane proteins, in addition to viral glycoproteins and viral genomic RNA. Gag binding to the PM is regulated by cellular factors, including PM-specific phospholipid PI(4,5)P2 and tRNAs, both of which bind the highly basic region in the matrix domain of Gag. In this article, we review our current understanding of the roles played by cellular lipids and tRNAs in specific localization of HIV-1 Gag to the PM. Furthermore, we examine the effects of PM-bound Gag on the organization of the PM bilayer and discuss how the reorganization of the PM at the virus assembly site potentially contributes to the enrichment of host transmembrane proteins in the HIV-1 particle. Since some of these host transmembrane proteins alter release, attachment, or infectivity of the nascent virions, the mechanism of Gag targeting to the PM and the nature of virus assembly sites have major implications in virus spread.
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26
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Bitetto G, Di Fonzo A. Nucleo-cytoplasmic transport defects and protein aggregates in neurodegeneration. Transl Neurodegener 2020; 9:25. [PMID: 32616075 PMCID: PMC7333321 DOI: 10.1186/s40035-020-00205-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 06/01/2020] [Indexed: 02/06/2023] Open
Abstract
In the ongoing process of uncovering molecular abnormalities in neurodegenerative diseases characterized by toxic protein aggregates, nucleo-cytoplasmic transport defects have an emerging role. Several pieces of evidence suggest a link between neuronal protein inclusions and nuclear pore complex (NPC) damage. These processes lead to oxidative stress, inefficient transcription, and aberrant DNA/RNA maintenance. The clinical and neuropathological spectrum of NPC defects is broad, ranging from physiological aging to a suite of neurodegenerative diseases. A better understanding of the shared pathways among these conditions may represent a significant step toward dissecting their underlying molecular mechanisms, opening the way to a real possibility of identifying common therapeutic targets.
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Affiliation(s)
- Giacomo Bitetto
- IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, Dino Ferrari Center, Neuroscience Section, Department of Pathophysiology and Transplantation, University of Milan, Via Francesco Sforza 35, 20122, Milan, Italy
| | - Alessio Di Fonzo
- IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, Dino Ferrari Center, Neuroscience Section, Department of Pathophysiology and Transplantation, University of Milan, Via Francesco Sforza 35, 20122, Milan, Italy.
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27
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Kuncha SK, Venkadasamy VL, Amudhan G, Dahate P, Kola SR, Pottabathini S, Kruparani SP, Shekar PC, Sankaranarayanan R. Genomic innovation of ATD alleviates mistranslation associated with multicellularity in Animalia. eLife 2020; 9:58118. [PMID: 32463355 PMCID: PMC7302879 DOI: 10.7554/elife.58118] [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: 04/21/2020] [Accepted: 05/27/2020] [Indexed: 12/26/2022] Open
Abstract
The emergence of multicellularity in Animalia is associated with increase in ROS and expansion of tRNA-isodecoders. tRNA expansion leads to misselection resulting in a critical error of L-Ala mischarged onto tRNAThr, which is proofread by Animalia-specific-tRNA Deacylase (ATD) in vitro. Here we show that in addition to ATD, threonyl-tRNA synthetase (ThrRS) can clear the error in cellular scenario. This two-tier functional redundancy for translation quality control breaks down during oxidative stress, wherein ThrRS is rendered inactive. Therefore, ATD knockout cells display pronounced sensitivity through increased mistranslation of threonine codons leading to cell death. Strikingly, we identify the emergence of ATD along with the error inducing tRNA species starting from Choanoflagellates thus uncovering an important genomic innovation required for multicellularity that occurred in unicellular ancestors of animals. The study further provides a plausible regulatory mechanism wherein the cellular fate of tRNAs can be switched from protein biosynthesis to non-canonical functions. The first animals evolved around 750 million years ago from single-celled ancestors that were most similar to modern-day organisms called the Choanoflagellates. As animals evolved they developed more complex body plans consisting of multiple cells organized into larger structures known as tissues and organs. Over time cells also evolved increased levels of molecules called reactive oxygen species, which are involved in many essential cell processes but are toxic at high levels. Animal cells also contain more types of molecules known as transfer ribonucleic acids, or tRNAs for short, than Choanoflagellate cells and other single-celled organisms. These molecules deliver building blocks known as amino acids to the machinery that produces new proteins. To ensure the proteins are made correctly, it is important that tRNAs deliver specific amino acids to the protein-building machinery in the right order. Each type of tRNA usually only pairs with a specific type of amino acid, but sometimes the enzymes involved in this process can make mistakes. Therefore, cells contain proofreading enzymes that help remove incorrect amino acids on tRNAs. One such enzyme – called ATD – is only found in animals. Experiments in test tubes reported that ATD removes an amino acid called alanine from tRNAs that are supposed to carry threonine, but its precise role in living cells remained unclear. To address this question, Kuncha et al. studied proofreading enzymes in human kidney cells. The experiments showed that, in addition to ATD, a second enzyme known as ThrRS was also able to correct alanine substitutions for threonines on tRNAs. However, reactive oxygen species inactivated the proofreading ability of ThrRS, suggesting ATD plays an essential role in correcting errors in cells containing high levels of reactive oxygen species. These findings suggest that as organisms evolved multiple cells and the levels of tRNA and oxidative stress increased, this led to the appearance of a new proofreading enzyme. Further studies found that ATD originated around 900 million years ago, before Choanoflagellates and animals diverged, indicating these enzymes might have helped to shape the evolution of animals. The next step following on from this work will be to understand the role of ATD in the cells of organs that are known to have particularly high levels of reactive oxygen species, such as testis and ovaries.
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Affiliation(s)
- Santosh Kumar Kuncha
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | | | | | - Priyanka Dahate
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | - Sankara Rao Kola
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | | | | | - P Chandra Shekar
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
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28
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Castro-González L, Alvarez-Idaboy JR, Galano A. Computationally Designed Sesamol Derivatives Proposed as Potent Antioxidants. ACS OMEGA 2020; 5:9566-9575. [PMID: 32363309 PMCID: PMC7191856 DOI: 10.1021/acsomega.0c00898] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 04/03/2020] [Indexed: 05/14/2023]
Abstract
Oxidative stress has been recognized to play an important role in several diseases, such as Parkinson's and Alzheimer's disease, which justifies the beneficial effects of antioxidants in ameliorating the deleterious effects of these health disorders. Sesamol, in particular, has been investigated for the treatment of several conditions because of its antioxidant properties. This article reports a rational computational design of new sesamol derivatives. They were constructed by adding four functional groups (-OH, -NH2, -COOH, and -SH) in three different positions of the sesamol molecular framework. A total of 50 derivatives between mono-, di-, and trisubstituted compounds were obtained. All the derivatives were evaluated and compared with a reference set of commercial neuroprotective drugs. The estimated properties are absorption, distribution, metabolism, excretion, toxicity, and synthetic accessibility. Selection and elimination scores were used to choose a first set of promising candidates. Acid-based properties and reactivity indexes were then estimated using the density functional theory. Four sesamol derivatives were finally selected, which are hypothesized to be potent antioxidants, even better than sesamol and Trolox for that purpose.
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Affiliation(s)
- Laura
M. Castro-González
- Departamento
de Física y Química Teórica, Facultad de Química, Universidad Nacional Autónoma de México, México DF 04510, Mexico
| | - Juan Raúl Alvarez-Idaboy
- Departamento
de Física y Química Teórica, Facultad de Química, Universidad Nacional Autónoma de México, México DF 04510, Mexico
| | - Annia Galano
- Departamento
de Química, Universidad Autónoma
Metropolitana-Iztapalapa, San Rafael Atlixco 186, Col. Vicentina. Iztapalapa. C. P., México DF 09340, Mexico
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29
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Abstract
Over the past decades, tRNA was found to be a rich hub of RNA modifications such as 1-methyladenosine and 5-methycytosine modifications and others, holding more than half of all modifications occurring in RNA molecules. Moreover, tRNA was discovered to be a source of various small noncoding RNA species, such as the stress induced angiogenin cleaved tRNA halves (tiRNA) or the miRNA like tRNA derived fragments. tRNA cleavage under stress was fist discovered in bacteria and later was found to be conserved across different species, including mammals. Under cellular stress conditions, tRNA undergoes conformational changes and angiogenin cleaves it into 3' and 5' halves. 5'tiRNA halves were shown to repress protein translations. tRNA cleavage is thought of to be a cytoprotective mechanism by which cells evade apoptosis, however some data hints to the opposite; that tiRNA are cytotoxic or at least related to apoptosis initiation. tRNA cleavage also was shown to be affected by tRNA modifications via different enzymes in the cytosol and mitochondria. In this review, we will highlight the biology of tRNA cleavage, show the evidence of it being cytoprotective or a marker of cell death and shed a light on its role in disease models and human diseases as well as possible future directions in this field of RNA research.
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Affiliation(s)
- Sherif Rashad
- Department of Neurosurgery; Department of Neurosurgical Engineering and Translational Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Kuniyasu Niizuma
- Department of Neurosurgery; Department of Neurosurgical Engineering and Translational Neuroscience, Tohoku University Graduate School of Medicine; Department of Neurosurgical Engineering and Translational Neuroscience, Graduate School of Biomedical Engineering, Tohoku University, Sendai, Japan
| | - Teiji Tominaga
- Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan
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30
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Pizzinga M, Harvey RF, Garland GD, Mordue R, Dezi V, Ramakrishna M, Sfakianos A, Monti M, Mulroney TE, Poyry T, Willis AE. The cell stress response: extreme times call for post‐transcriptional measures. WILEY INTERDISCIPLINARY REVIEWS-RNA 2019; 11:e1578. [DOI: 10.1002/wrna.1578] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 10/09/2019] [Accepted: 10/16/2019] [Indexed: 12/26/2022]
Affiliation(s)
| | | | | | - Ryan Mordue
- MRC Toxicology Unit University of Cambridge Leicester UK
| | - Veronica Dezi
- MRC Toxicology Unit University of Cambridge Leicester UK
| | | | | | - Mie Monti
- MRC Toxicology Unit University of Cambridge Leicester UK
| | | | - Tuija Poyry
- MRC Toxicology Unit University of Cambridge Leicester UK
| | - Anne E. Willis
- MRC Toxicology Unit University of Cambridge Leicester UK
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31
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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.
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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
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