1
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Guarnacci M, Zhang PH, Kanchi M, Hung YT, Lin H, Shirokikh NE, Yang L, Preiss T. Substrate diversity of NSUN enzymes and links of 5-methylcytosine to mRNA translation and turnover. Life Sci Alliance 2024; 7:e202402613. [PMID: 38986569 PMCID: PMC11235314 DOI: 10.26508/lsa.202402613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 06/28/2024] [Accepted: 06/28/2024] [Indexed: 07/12/2024] Open
Abstract
Maps of the RNA modification 5-methylcytosine (m5C) often diverge markedly not only because of differences in detection methods, data depand analysis pipelines but also biological factors. We re-analysed bisulfite RNA sequencing datasets from five human cell lines and seven tissues using a coherent m5C site calling pipeline. With the resulting union list of 6,393 m5C sites, we studied site distribution, enzymology, interaction with RNA-binding proteins and molecular function. We confirmed tRNA:m5C methyltransferases NSUN2 and NSUN6 as the main mRNA m5C "writers," but further showed that the rRNA:m5C methyltransferase NSUN5 can also modify mRNA. Each enzyme recognises mRNA features that strongly resemble their canonical substrates. By analysing proximity between mRNA m5C sites and footprints of RNA-binding proteins, we identified new candidates for functional interactions, including the RNA helicases DDX3X, involved in mRNA translation, and UPF1, an mRNA decay factor. We found that lack of NSUN2 in HeLa cells affected both steady-state levels of, and UPF1-binding to, target mRNAs. Our studies emphasise the emerging diversity of m5C writers and readers and their effect on mRNA function.
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Affiliation(s)
- Marco Guarnacci
- https://ror.org/019wvm592 Shine-Dalgarno Centre for RNA Innovation, Division of Genome Science and Cancer, John Curtin School of Medical Research, Australian National University, Canberra, Australia
| | - Pei-Hong Zhang
- Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
- Center for Molecular Medicine, Children's Hospital, Shanghai Key Laboratory of Medical Epigenetics, International Laboratory of Medical Epigenetics and Metabolism, Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Madhu Kanchi
- https://ror.org/019wvm592 Shine-Dalgarno Centre for RNA Innovation, Division of Genome Science and Cancer, John Curtin School of Medical Research, Australian National University, Canberra, Australia
| | - Yu-Ting Hung
- https://ror.org/019wvm592 Shine-Dalgarno Centre for RNA Innovation, Division of Genome Science and Cancer, John Curtin School of Medical Research, Australian National University, Canberra, Australia
| | - Hanrong Lin
- https://ror.org/019wvm592 Shine-Dalgarno Centre for RNA Innovation, Division of Genome Science and Cancer, John Curtin School of Medical Research, Australian National University, Canberra, Australia
| | - Nikolay E Shirokikh
- https://ror.org/019wvm592 Shine-Dalgarno Centre for RNA Innovation, Division of Genome Science and Cancer, John Curtin School of Medical Research, Australian National University, Canberra, Australia
| | - Li Yang
- Center for Molecular Medicine, Children's Hospital, Shanghai Key Laboratory of Medical Epigenetics, International Laboratory of Medical Epigenetics and Metabolism, Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Thomas Preiss
- https://ror.org/019wvm592 Shine-Dalgarno Centre for RNA Innovation, Division of Genome Science and Cancer, John Curtin School of Medical Research, Australian National University, Canberra, Australia
- Victor Chang Cardiac Research Institute, Sydney, Australia
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2
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Wu Z, Zhou R, Li B, Cao M, Wang W, Li X. Methylation modifications in tRNA and associated disorders: Current research and potential therapeutic targets. Cell Prolif 2024:e13692. [PMID: 38943267 DOI: 10.1111/cpr.13692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2024] [Revised: 05/14/2024] [Accepted: 06/03/2024] [Indexed: 07/01/2024] Open
Abstract
High-throughput sequencing has sparked increased research interest in RNA modifications, particularly tRNA methylation, and its connection to various diseases. However, the precise mechanisms underpinning the development of these diseases remain largely elusive. This review sheds light on the roles of several tRNA methylations (m1A, m3C, m5C, m1G, m2G, m7G, m5U, and Nm) in diverse biological functions, including metabolic processing, stability, protein interactions, and mitochondrial activities. It further outlines diseases linked to aberrant tRNA modifications, related enzymes, and potential underlying mechanisms. Moreover, disruptions in tRNA regulation and abnormalities in tRNA-derived small RNAs (tsRNAs) contribute to disease pathogenesis, highlighting their potential as biomarkers for disease diagnosis. The review also delves into the exploration of drugs development targeting tRNA methylation enzymes, emphasizing the therapeutic prospects of modulating these processes. Continued research is imperative for a comprehensive comprehension and integration of these molecular mechanisms in disease diagnosis and treatment.
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Affiliation(s)
- Zhijing Wu
- Department of General Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Ruixin Zhou
- Department of General Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Baizao Li
- Department of General Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Mingyu Cao
- Department of General Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Wenlong Wang
- Department of Breast Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, China
- Clinical Research Center for Breast Cancer in Hunan Province, Changsha, Hunan, China
| | - Xinying Li
- Department of General Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China
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3
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Guarnacci M, Preiss T. The je ne sais quoi of 5-methylcytosine in messenger RNA. RNA (NEW YORK, N.Y.) 2024; 30:560-569. [PMID: 38531644 PMCID: PMC11019750 DOI: 10.1261/rna.079982.124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Accepted: 02/09/2024] [Indexed: 03/28/2024]
Abstract
The potential presence of 5-methylcytosine as a sparse internal modification of mRNA was first raised in 1975, and a first map of the modification was also part of the epitranscriptomics "big bang" in 2012. Since then, the evidence for its presence in mRNA has firmed up, and initial insights have been gained into the molecular function and broader biological relevance of 5-methylcytosine when present in mRNA. Here, we summarize the status quo of the field, outline some of its current challenges, and suggest how to address them in future work.
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Affiliation(s)
- Marco Guarnacci
- Shine-Dalgarno Centre for RNA Innovation, Division of Genome Science and Cancer, John Curtin School of Medical Research, Australian National University, Canberra 2601, Australian Capital Territory, Australia
| | - Thomas Preiss
- Shine-Dalgarno Centre for RNA Innovation, Division of Genome Science and Cancer, John Curtin School of Medical Research, Australian National University, Canberra 2601, Australian Capital Territory, Australia
- Victor Chang Cardiac Research Institute, Sydney, New South Wales 2010, Australia
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4
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Zhang T, Zhao F, Li J, Sun X, Zhang X, Wang H, Fan P, Lai L, Li Z, Sui T. Programmable RNA 5-methylcytosine (m5C) modification of cellular RNAs by dCasRx conjugated methyltransferase and demethylase. Nucleic Acids Res 2024; 52:2776-2791. [PMID: 38366553 PMCID: PMC11014266 DOI: 10.1093/nar/gkae110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 01/23/2024] [Accepted: 02/05/2024] [Indexed: 02/18/2024] Open
Abstract
5-Methylcytosine (m5C), an abundant RNA modification, plays a crucial role in regulating RNA fate and gene expression. While recent progress has been made in understanding the biological roles of m5C, the inability to introduce m5C at specific sites within transcripts has hindered efforts to elucidate direct links between specific m5C and phenotypic outcomes. Here, we developed a CRISPR-Cas13d-based tool, named reengineered m5C modification system (termed 'RCMS'), for targeted m5C methylation and demethylation in specific transcripts. The RCMS editors consist of a nuclear-localized dCasRx conjugated to either a methyltransferase, NSUN2/NSUN6, or a demethylase, the catalytic domain of mouse Tet2 (ten-eleven translocation 2), enabling the manipulation of methylation events at precise m5C sites. We demonstrate that the RCMS editors can direct site-specific m5C incorporation and demethylation. Furthermore, we confirm their effectiveness in modulating m5C levels within transfer RNAs and their ability to induce changes in transcript abundance and cell proliferation through m5C-mediated mechanisms. These findings collectively establish RCMS editors as a focused epitranscriptome engineering tool, facilitating the identification of individual m5C alterations and their consequential effects.
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Affiliation(s)
- Tao Zhang
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis and College of Veterinary Medicine, Jilin University, Changchun, Jilin 130000,China
| | - Feiyu Zhao
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis and College of Veterinary Medicine, Jilin University, Changchun, Jilin 130000,China
| | - Jinze Li
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis and College of Veterinary Medicine, Jilin University, Changchun, Jilin 130000,China
| | - Xiaodi Sun
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis and College of Veterinary Medicine, Jilin University, Changchun, Jilin 130000,China
| | - Xiyun Zhang
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis and College of Veterinary Medicine, Jilin University, Changchun, Jilin 130000,China
| | - Hejun Wang
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis and College of Veterinary Medicine, Jilin University, Changchun, Jilin 130000,China
| | - Peng Fan
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis and College of Veterinary Medicine, Jilin University, Changchun, Jilin 130000,China
| | - Liangxue Lai
- Key Laboratory of Regenerative Biology, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, Guangdong 510530, China
| | - Zhanjun Li
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis and College of Veterinary Medicine, Jilin University, Changchun, Jilin 130000,China
| | - Tingting Sui
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis and College of Veterinary Medicine, Jilin University, Changchun, Jilin 130000,China
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5
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Zhao Y, Xing C, Peng H. ALYREF (Aly/REF export factor): A potential biomarker for predicting cancer occurrence and therapeutic efficacy. Life Sci 2024; 338:122372. [PMID: 38135116 DOI: 10.1016/j.lfs.2023.122372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 12/09/2023] [Accepted: 12/18/2023] [Indexed: 12/24/2023]
Abstract
5-Methylcytosine (m5C) methylation is present in almost all types of RNA as an essential epigenetic modification. It is dynamically modulated by its associated enzymes, including m5C methyltransferases (NSUN, DNMT and TRDMT family members), demethylases (TET family and ALKBH1) and binding proteins (YTHDF2, ALYREF and YBX1). Among them, aberrant expression of the RNA-binding protein ALYREF can facilitate a variety of malignant phenotypes such as maintenance of proliferation, malignant heterogeneity, metastasis, and drug resistance to cell death through different regulatory mechanisms, including pre-mRNA processing, mRNA stability, and nuclear-cytoplasmic shuttling. The induction of these cellular processes by ALYREF results in treatment resistance and poor outcomes for patients. However, there are currently few reports of clinical applications or drug trials related to ALYREF. In addition, the looming observations on the role of ALYREF in the mechanisms of carcinogenesis and disease prognosis have triggered considerable interest, but critical evidence is not available. For example, animal experiments and ALYREF small molecule inhibitor trials. In this review, we, therefore, revisit the literature on ALYREF and highlight its importance as a prognostic biomarker for early prevention and as a therapeutic target.
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Affiliation(s)
- Yan Zhao
- Department of Hematology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, China
| | - Cheng Xing
- Department of Hematology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, China
| | - Hongling Peng
- Department of Hematology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, China; Hunan Key Laboratory of Tumor Models and Individualized Medicine, Changsha, Hunan 410011, China; Hunan Engineering Research Center of Cell Immunotherapy for Hematopoietic Malignancies, Changsha, Hunan 410011, China.
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6
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Tao Y, Felber JG, Zou Z, Njomen E, Remsberg JR, Ogasawara D, Ye C, Melillo B, Schreiber SL, He C, Remillard D, Cravatt BF. Chemical Proteomic Discovery of Isotype-Selective Covalent Inhibitors of the RNA Methyltransferase NSUN2. Angew Chem Int Ed Engl 2023; 62:e202311924. [PMID: 37909922 PMCID: PMC10999112 DOI: 10.1002/anie.202311924] [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: 08/16/2023] [Revised: 10/26/2023] [Accepted: 10/29/2023] [Indexed: 11/03/2023]
Abstract
5-Methylcytosine (m5 C) is an RNA modification prevalent on tRNAs, where it can protect tRNAs from endonucleolytic cleavage to maintain protein synthesis. The NSUN family (NSUN1-7 in humans) of RNA methyltransferases are capable of installing the methyl group onto the C5 position of cytosines in RNA. NSUNs are implicated in a wide range of (patho)physiological processes, but selective and cell-active inhibitors of these enzymes are lacking. Here, we use cysteine-directed activity-based protein profiling (ABPP) to discover azetidine acrylamides that act as stereoselective covalent inhibitors of human NSUN2. Despite targeting a conserved catalytic cysteine in the NSUN family, the NSUN2 inhibitors show negligible cross-reactivity with other human NSUNs and exhibit good proteome-wide selectivity. We verify that the azetidine acrylamides inhibit the catalytic activity of recombinant NSUN2, but not NSUN6, and demonstrate that these compounds stereoselectively disrupt NSUN2-tRNA interactions in cancer cells, leading to a global reduction in tRNA m5 C content. Our findings thus highlight the potential to create isotype-selective and cell-active inhibitors of NSUN2 with covalent chemistry targeting a conserved catalytic cysteine.
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Affiliation(s)
- Yongfeng Tao
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550N. Torrey Pines Road, La Jolla, CA-92307, USA
| | - Jan G Felber
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550N. Torrey Pines Road, La Jolla, CA-92307, USA
- LMU Munich, Department of Pharmacy, Butenandtstr. 5-13, 81377, Munich, Germany
| | - Zhongyu Zou
- Department of Chemistry, The University of Chicago, 929 East 57th Street, GCIS E319B, Chicago, IL-60637, USA
| | - Evert Njomen
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550N. Torrey Pines Road, La Jolla, CA-92307, USA
| | - Jarrett R Remsberg
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550N. Torrey Pines Road, La Jolla, CA-92307, USA
- Current address: Belharra Therapeutics, 3985 Sorrento Valley Blvd Suite C, San Diego, CA-92121, USA
| | - Daisuke Ogasawara
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550N. Torrey Pines Road, La Jolla, CA-92307, USA
| | - Chang Ye
- Department of Chemistry, The University of Chicago, 929 East 57th Street, GCIS E319B, Chicago, IL-60637, USA
| | - Bruno Melillo
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550N. Torrey Pines Road, La Jolla, CA-92307, USA
- Chemical Biology and Therapeutics Science Program, Broad Institute of Harvard and MIT, 415 Main Street, Cambridge, MA-02142, USA
| | - Stuart L Schreiber
- Chemical Biology and Therapeutics Science Program, Broad Institute of Harvard and MIT, 415 Main Street, Cambridge, MA-02142, USA
- Harvard University, Department of Chemistry and Chemical Biology, 12 Oxford Street, MA-02138, Cambridge, USA
| | - Chuan He
- Department of Chemistry, The University of Chicago, 929 East 57th Street, GCIS E319B, Chicago, IL-60637, USA
- Howard Hughes Medical Institute, The University of Chicago, 929 East 57th Street, GCIS E319B, Chicago, IL-60637, USA
| | - David Remillard
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550N. Torrey Pines Road, La Jolla, CA-92307, USA
- Current address: Novartis, 10675 John Jay Hopkins Dr, San Diego, CA-92121, USA
| | - Benjamin F Cravatt
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550N. Torrey Pines Road, La Jolla, CA-92307, USA
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Li P, Wang W, Zhou R, Ding Y, Li X. The m 5 C methyltransferase NSUN2 promotes codon-dependent oncogenic translation by stabilising tRNA in anaplastic thyroid cancer. Clin Transl Med 2023; 13:e1466. [PMID: 37983928 PMCID: PMC10659772 DOI: 10.1002/ctm2.1466] [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: 04/20/2023] [Revised: 10/15/2023] [Accepted: 10/19/2023] [Indexed: 11/22/2023] Open
Abstract
BACKGROUND Translation dysregulation plays a crucial role in tumourigenesis and cancer progression. Oncogenic translation relies on the stability and availability of tRNAs for protein synthesis, making them potential targets for cancer therapy. METHODS This study performed immunohistochemistry analysis to assess NSUN2 levels in thyroid cancer. Furthermore, to elucidate the impact of NSUN2 on anaplastic thyroid cancer (ATC) malignancy, phenotypic assays were conducted. Drug inhibition and time-dependent plots were employed to analyse drug resistance. Liquid chromatography-mass spectrometry and bisulphite sequencing were used to investigate the m5 C methylation of tRNA at both global and single-base levels. Puromycin intake and high-frequency codon reporter assays verified the protein translation level. By combining mRNA and ribosome profiling, a series of downstream proteins and codon usage bias were identified. The acquired data were further validated by tRNA sequencing. RESULTS This study observed that the tRNA m5 C methyltransferase NSUN2 was up-regulated in ATC and is associated with dedifferentiation. Furthermore, NSUN2 knockdown repressed ATC formation, proliferation, invasion and migration both in vivo and in vitro. Moreover, NSUN2 repression enhanced the sensitivity of ATC to genotoxic drugs. Mechanically, NSUN2 catalyses tRNA structure-related m5 C modification, stabilising tRNA that maintains homeostasis and rapidly transports amino acids, particularly leucine. This stable tRNA has a substantially increased efficiency necessary to support a pro-cancer translation program including c-Myc, BCL2, RAB31, JUNB and TRAF2. Additionally, the NSUN2-mediated variations in m5C levels and different tRNA Leu iso-decoder families, partially contribute to a codon-dependent translation bias. Surprisingly, targeting NSUN2 disrupted the c-Myc to NSUN2 cycle in ATC. CONCLUSIONS This research revealed that a pro-tumour m5C methyltransferase, dynamic tRNA stability regulation and downstream oncogenes, c-Myc, elicits a codon-dependent oncogenic translation network that enhances ATC growth and formation. Furthermore, it provides new opportunities for targeting translation reprogramming in cancer cells.
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Affiliation(s)
- Peng Li
- Department of General SurgeryXiangya HospitalCentral South UniversityChangshaHunanChina
- National Clinical Research Center for Geriatric DisordersXiangya HospitalCentral South UniversityChangshaHunan ProvinceChina
- Department of Hepatobiliary SurgerySichuan Provincial People's HospitalSchool of MedicineUniversity of Electronic Science and Technology of ChinaChengduChina
| | - Wenlong Wang
- Department of General SurgeryXiangya HospitalCentral South UniversityChangshaHunanChina
- National Clinical Research Center for Geriatric DisordersXiangya HospitalCentral South UniversityChangshaHunan ProvinceChina
| | - Ruixin Zhou
- Department of General SurgeryXiangya HospitalCentral South UniversityChangshaHunanChina
| | - Ying Ding
- Department of General SurgeryXiangya HospitalCentral South UniversityChangshaHunanChina
| | - Xinying Li
- Department of General SurgeryXiangya HospitalCentral South UniversityChangshaHunanChina
- National Clinical Research Center for Geriatric DisordersXiangya HospitalCentral South UniversityChangshaHunan ProvinceChina
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8
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Hu S, Yang M, Xiao K, Yang Z, Cai L, Xie Y, Wang L, Wei R. Loss of NSUN6 inhibits osteosarcoma progression by downregulating EEF1A2 expression and activation of Akt/mTOR signaling pathway via m 5C methylation. Exp Ther Med 2023; 26:457. [PMID: 37614424 PMCID: PMC10443047 DOI: 10.3892/etm.2023.12156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 06/29/2023] [Indexed: 08/25/2023] Open
Abstract
As an important 5-methylcytidine (m5C) methyltransferase, NOP2/Sun RNA methyltransferase family member 6 (NSUN6) has been reported to play an important role in the progression of several diseases. However, the role of NSUN6 in the progression of osteosarcoma (OS) remains unclear. This study aimed to identify the role of NSUN6 in the progression of OS and clarify the potential molecular mechanism. The present study discovered that NSUN6 was upregulated in OS and a higher NSUN6 expression was a strong indicator for poorer prognosis of patients with OS. In addition, the loss of NSUN6 led to reduced proliferation, migration and invasion of OS cells. Through bioinformatics analysis, RNA immunoprecipitation (RIP) and methylated RIP assays, eukaryotic elongation factor 1 α-2 (EEF1A2) was identified and validated as a potential target of NSUN6 in OS. Mechanistically, the expression of EEF1A2 was significantly suppressed following NSUN6 knockdown due to reduced EEF1A2 mRNA stability in an m5C-dependent manner. Meanwhile, NSUN6 deficiency inhibited m5C-dependent activation of Akt/mTOR signaling pathway. In addition, genetic overexpression of EEF1A2 or pharmacological activation of the Akt signaling pathway counteracted the suppressive effects of NSUN6 deficiency on the proliferation, invasion and migration of OS cells. The current findings suggested that NSUN6 may serve as a potential therapeutic target for OS treatment.
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Affiliation(s)
- Sang Hu
- Department of Spine Surgery and Musculoskeletal Tumor, Zhongnan Hospital of Wuhan University, Wuhan, Hubei 430071, P.R. China
| | - Min Yang
- Department of Orthopedics, Jingzhou Hospital Affiliated to Yangtze University, Jingzhou, Hubei 434020, P.R. China
| | - Kangwen Xiao
- Department of Spine Surgery and Musculoskeletal Tumor, Zhongnan Hospital of Wuhan University, Wuhan, Hubei 430071, P.R. China
| | - Zhiqiang Yang
- Department of Spine Surgery and Musculoskeletal Tumor, Zhongnan Hospital of Wuhan University, Wuhan, Hubei 430071, P.R. China
| | - Lin Cai
- Department of Spine Surgery and Musculoskeletal Tumor, Zhongnan Hospital of Wuhan University, Wuhan, Hubei 430071, P.R. China
| | - Yuanlong Xie
- Department of Spine Surgery and Musculoskeletal Tumor, Zhongnan Hospital of Wuhan University, Wuhan, Hubei 430071, P.R. China
| | - Linlong Wang
- Department of Spine Surgery and Musculoskeletal Tumor, Zhongnan Hospital of Wuhan University, Wuhan, Hubei 430071, P.R. China
| | - Renxiong Wei
- Department of Spine Surgery and Musculoskeletal Tumor, Zhongnan Hospital of Wuhan University, Wuhan, Hubei 430071, P.R. China
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9
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Wang YY, Tian Y, Li YZ, Liu YF, Zhao YY, Chen LH, Zhang C. The role of m5C methyltransferases in cardiovascular diseases. Front Cardiovasc Med 2023; 10:1225014. [PMID: 37476573 PMCID: PMC10354557 DOI: 10.3389/fcvm.2023.1225014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 06/19/2023] [Indexed: 07/22/2023] Open
Abstract
The global leading cause of death is cardiovascular disease (CVD). Although advances in prevention and treatment have been made, the role of RNA epigenetics in CVD is not fully understood. Studies have found that RNA modifications regulate gene expression in mammalian cells, and m5C (5-methylcytosine) is a recently discovered RNA modification that plays a role in gene regulation. As a result of these developments, there has been renewed interest in elucidating the nature and function of RNA "epitranscriptomic" modifications. Recent studies on m5C RNA methylomes, their functions, and the proteins that initiate, translate and manipulate this modification are discussed in this review. This review improves the understanding of m5C modifications and their properties, functions, and implications in cardiac pathologies, including cardiomyopathy, heart failure, and atherosclerosis.
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Affiliation(s)
- Yan-Yue Wang
- Key Lab for Arteriosclerology of Hunan Province, Institute of Cardiovascular Disease, Hengyang Medical School, University of South China, Hengyang, China
| | - Yuan Tian
- Key Lab for Arteriosclerology of Hunan Province, Institute of Cardiovascular Disease, Hengyang Medical School, University of South China, Hengyang, China
| | - Yong-Zhen Li
- Key Lab for Arteriosclerology of Hunan Province, Institute of Cardiovascular Disease, Hengyang Medical School, University of South China, Hengyang, China
| | - Yi-Fan Liu
- ResearchLaboratory of Translational Medicine, Hengyang Medical School, University of South China, Hengyang, China
| | - Yu-Yan Zhao
- Key Lab for Arteriosclerology of Hunan Province, Institute of Cardiovascular Disease, Hengyang Medical School, University of South China, Hengyang, China
| | - Lin-Hui Chen
- Key Lab for Arteriosclerology of Hunan Province, Institute of Cardiovascular Disease, Hengyang Medical School, University of South China, Hengyang, China
| | - Chi Zhang
- Key Lab for Arteriosclerology of Hunan Province, Institute of Cardiovascular Disease, Hengyang Medical School, University of South China, Hengyang, China
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10
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Zhou Y, Hong Q, Xu W, Chen W, Xie X, Zhuang D, Lai M, Fu D, Xu Z, Wang M, Zhou W, Liu H. Differential expression profiling of tRNA-Derived small RNAs and their potential roles in methamphetamine self-administered rats. Front Genet 2023; 14:1088498. [PMID: 36845381 PMCID: PMC9945332 DOI: 10.3389/fgene.2023.1088498] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 01/18/2023] [Indexed: 02/05/2023] Open
Abstract
Transfer RNA-derived small RNAs (tsRNAs) are a novel class of short, non-coding RNAs that are closely associated with the pathogenesis of various diseases. Accumulating evidence has demonstrated their critical functional roles as regulatory factors in gene expression regulation, protein translation regulation, regulation of various cellular activities, immune mediation, and response to stress. However, the underlying mechanisms by which tRFs & tiRNAs affect methamphetamine-induced pathophysiological processes are largely unknown. In this study, we used a combination of small RNA sequencing, quantitative reverse transcription-polymerase chain reaction (qRT‒PCR), bioinformatics, and luciferase reporter assays to screen the expression profiles and identify the functional roles of tRFs and tiRNAs in the nucleus accumbens (NAc) of methamphetamine self-administration rat models. A total of 461 tRFs & tiRNAs were identified in the NAc of rats after 14 days of methamphetamine self-administration training. Of those, 132 tRFs & tiRNAs were significantly differentially expressed: 59 were significantly upregulated, whereas 73 were significantly downregulated in the rats with methamphetamine self-administration. Decreased expression levels of tiRNA-1-34-Lys-CTT-1 and tRF-1-32-Gly-GCC-2-M2, as well as increased expression levels of tRF-1-16-Ala-TGC-4 in the METH group compared with the saline control were validated by using RT‒PCR. Then, bioinformatic analysis was performed to analyse the possible biological functions of tRFs & tiRNAs in methamphetamine-induced pathogenesis. Furthermore, tRF-1-32-Gly-GCC-2-M2 was identified to target BDNF using the luciferase reporter assay. An altered tsRNA expression pattern was proven, and tRF-1-32-Gly-GCC-2-M2 was shown to be involved in methamphetamine-induced pathophysiologic processes by targeting BDNF. The current study provides new insights for future investigations to explore the mechanisms and therapeutic methods for methamphetamine addiction.
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Affiliation(s)
- Yun Zhou
- School of Medicine, Ningbo University, Laboratory of Behavioral Neuroscience, Ningbo Kangning Hospital, Ningbo, Zhejiang, China
| | - Qingxiao Hong
- School of Medicine, Ningbo University, Laboratory of Behavioral Neuroscience, Ningbo Kangning Hospital, Ningbo, Zhejiang, China,Key Laboratory of Addiction Research of Zhejiang Province, Ningbo, Zhejiang, China
| | - Wenjin Xu
- School of Medicine, Ningbo University, Laboratory of Behavioral Neuroscience, Ningbo Kangning Hospital, Ningbo, Zhejiang, China,Key Laboratory of Addiction Research of Zhejiang Province, Ningbo, Zhejiang, China
| | - Weisheng Chen
- School of Medicine, Ningbo University, Laboratory of Behavioral Neuroscience, Ningbo Kangning Hospital, Ningbo, Zhejiang, China,Key Laboratory of Addiction Research of Zhejiang Province, Ningbo, Zhejiang, China
| | - Xiaohu Xie
- School of Medicine, Ningbo University, Laboratory of Behavioral Neuroscience, Ningbo Kangning Hospital, Ningbo, Zhejiang, China,Key Laboratory of Addiction Research of Zhejiang Province, Ningbo, Zhejiang, China
| | - Dingding Zhuang
- School of Medicine, Ningbo University, Laboratory of Behavioral Neuroscience, Ningbo Kangning Hospital, Ningbo, Zhejiang, China,Key Laboratory of Addiction Research of Zhejiang Province, Ningbo, Zhejiang, China
| | - Miaojun Lai
- School of Medicine, Ningbo University, Laboratory of Behavioral Neuroscience, Ningbo Kangning Hospital, Ningbo, Zhejiang, China,Key Laboratory of Addiction Research of Zhejiang Province, Ningbo, Zhejiang, China
| | - Dan Fu
- School of Medicine, Ningbo University, Laboratory of Behavioral Neuroscience, Ningbo Kangning Hospital, Ningbo, Zhejiang, China,Key Laboratory of Addiction Research of Zhejiang Province, Ningbo, Zhejiang, China
| | - Zemin Xu
- School of Medicine, Ningbo University, Laboratory of Behavioral Neuroscience, Ningbo Kangning Hospital, Ningbo, Zhejiang, China,Key Laboratory of Addiction Research of Zhejiang Province, Ningbo, Zhejiang, China
| | - Majie Wang
- School of Medicine, Ningbo University, Laboratory of Behavioral Neuroscience, Ningbo Kangning Hospital, Ningbo, Zhejiang, China,Key Laboratory of Addiction Research of Zhejiang Province, Ningbo, Zhejiang, China
| | - Wenhua Zhou
- School of Medicine, Ningbo University, Laboratory of Behavioral Neuroscience, Ningbo Kangning Hospital, Ningbo, Zhejiang, China,Key Laboratory of Addiction Research of Zhejiang Province, Ningbo, Zhejiang, China,*Correspondence: Wenhua Zhou, ; Huifen Liu,
| | - Huifen Liu
- School of Medicine, Ningbo University, Laboratory of Behavioral Neuroscience, Ningbo Kangning Hospital, Ningbo, Zhejiang, China,Key Laboratory of Addiction Research of Zhejiang Province, Ningbo, Zhejiang, China,*Correspondence: Wenhua Zhou, ; Huifen Liu,
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11
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Cavallin I, Bartosovic M, Skalicky T, Rengaraj P, Demko M, Schmidt-Dengler MC, Drino A, Helm M, Vanacova S. HITS-CLIP analysis of human ALKBH8 reveals interactions with fully processed substrate tRNAs and with specific noncoding RNAs. RNA (NEW YORK, N.Y.) 2022; 28:1568-1581. [PMID: 36192131 PMCID: PMC9670814 DOI: 10.1261/rna.079421.122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 09/09/2022] [Indexed: 06/16/2023]
Abstract
Transfer RNAs acquire a large plethora of chemical modifications. Among those, modifications of the anticodon loop play important roles in translational fidelity and tRNA stability. Four human wobble U-containing tRNAs obtain 5-methoxycarbonylmethyluridine (mcm5U34) or 5-methoxycarbonylmethyl-2-thiouridine (mcm5s2U34), which play a role in decoding. This mark involves a cascade of enzymatic activities. The last step is mediated by alkylation repair homolog 8 (ALKBH8). In this study, we performed a transcriptome-wide analysis of the repertoire of ALKBH8 RNA targets. Using a combination of HITS-CLIP and RIP-seq analyses, we uncover ALKBH8-bound RNAs. We show that ALKBH8 targets fully processed and CCA modified tRNAs. Our analyses uncovered the previously known set of wobble U-containing tRNAs. In addition, both our approaches revealed ALKBH8 binding to several other types of noncoding RNAs, in particular C/D box snoRNAs.
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Affiliation(s)
- Ivana Cavallin
- Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic
| | - Marek Bartosovic
- Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic
| | - Tomas Skalicky
- Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, 370 05 České Budějovice, Czech Republic
| | - Praveenkumar Rengaraj
- Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic
| | - Martin Demko
- Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic
| | | | - Aleksej Drino
- Medical University of Vienna, Center for Anatomy and Cell Biology, 1090 Vienna, Austria
| | - Mark Helm
- Johannes Gutenberg-Universität Mainz, Institute of Pharmaceutical and Biomedical Science (IPBS), D-55128 Mainz, Germany
| | - Stepanka Vanacova
- Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic
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12
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Kossinova OA, Gopanenko AV, Babaylova ES, Tupikin AE, Kabilov MR, Malygin AA, Karpova GG. Reorganization of the Landscape of Translated mRNAs in NSUN2-Deficient Cells and Specific Features of NSUN2 Target mRNAs. Int J Mol Sci 2022; 23:ijms23179740. [PMID: 36077143 PMCID: PMC9456143 DOI: 10.3390/ijms23179740] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 08/22/2022] [Accepted: 08/24/2022] [Indexed: 11/16/2022] Open
Abstract
The RNA cytosine C5 methyltransferase NSUN2 has a variety of RNA substrates and plays an important role in mRNA metabolism. NSUN2 binds to specific sequences enriched in exosomal mRNAs, suggesting its possible involvement in the sorting of mRNAs into exosomes. We applied the photoactivatable.4-thiouridine-enhanced cross-linking and immunoprecipitation assay involving high-throughput RNA sequencing (RNA-seq) to HEK293T cells to determine NSUN2 mRNA targets. NSUN2 cross-linking sites were found in more than one hundred relatively abundant mRNAs with a high GC content and a pronounced secondary structure. Then, utilizing RNA-seq for the total and polysome-associated mRNA from HEK293T cells with and without the knockdown of NSUN2, we identified differentially expressed genes, as well as genes with altered translational efficiency (GATEs). It turned out that the up-regulated GATE mRNAs were much shorter on average than the down-regulated ones, and their GC content was higher; moreover, they contained motifs with C residues located in GC-rich environments. Our findings reveal the specific features of mRNAs that make them potential targets for NSUN2 and expand our understanding of the role of NSUN2 in controlling translation and, possibly, in mRNA sorting into exosomes implemented through the methylation of cytosine residues.
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13
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Arguello AE, Li A, Sun X, Eggert TW, Mairhofer E, Kleiner RE. Reactivity-dependent profiling of RNA 5-methylcytidine dioxygenases. Nat Commun 2022; 13:4176. [PMID: 35853884 PMCID: PMC9296451 DOI: 10.1038/s41467-022-31876-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 07/05/2022] [Indexed: 01/10/2023] Open
Abstract
Epitranscriptomic RNA modifications can regulate fundamental biological processes, but we lack approaches to map modification sites and probe writer enzymes. Here we present a chemoproteomic strategy to characterize RNA 5-methylcytidine (m5C) dioxygenase enzymes in their native context based upon metabolic labeling and activity-based crosslinking with 5-ethynylcytidine (5-EC). We profile m5C dioxygenases in human cells including ALKBH1 and TET2 and show that ALKBH1 is the major hm5C- and f5C-forming enzyme in RNA. Further, we map ALKBH1 modification sites transcriptome-wide using 5-EC-iCLIP and ARP-based sequencing to identify ALKBH1-dependent m5C oxidation in a variety of tRNAs and mRNAs and analyze ALKBH1 substrate specificity in vitro. We also apply targeted pyridine borane-mediated sequencing to measure f5C sites on select tRNA. Finally, we show that f5C at the wobble position of tRNA-Leu-CAA plays a role in decoding Leu codons under stress. Our work provides powerful chemical approaches for studying RNA m5C dioxygenases and mapping oxidative m5C modifications and reveals the existence of novel epitranscriptomic pathways for regulating RNA function. Kleiner and co-workers profile RNA 5-methylcytidine (m5C) dioxygenase enzymes using an activity-based metabolic probing strategy. They reveal ALKBH1 as the major 5-formylcytidine (f5C) writer and characterize modification sites across mRNA and tRNA.
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Affiliation(s)
- A Emilia Arguello
- Department of Chemistry, Princeton University, Princeton, NJ, 08544, USA
| | - Ang Li
- Department of Chemistry, Princeton University, Princeton, NJ, 08544, USA
| | - Xuemeng Sun
- Department of Chemistry, Princeton University, Princeton, NJ, 08544, USA
| | - Tanner W Eggert
- Department of Chemistry, Princeton University, Princeton, NJ, 08544, USA
| | | | - Ralph E Kleiner
- Department of Chemistry, Princeton University, Princeton, NJ, 08544, USA.
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14
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Brégeon D, Pecqueur L, Toubdji S, Sudol C, Lombard M, Fontecave M, de Crécy-Lagard V, Motorin Y, Helm M, Hamdane D. Dihydrouridine in the Transcriptome: New Life for This Ancient RNA Chemical Modification. ACS Chem Biol 2022; 17:1638-1657. [PMID: 35737906 DOI: 10.1021/acschembio.2c00307] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Until recently, post-transcriptional modifications of RNA were largely restricted to noncoding RNA species. However, this belief seems to have quickly dissipated with the growing number of new modifications found in mRNA that were originally thought to be primarily tRNA-specific, such as dihydrouridine. Recently, transcriptomic profiling, metabolic labeling, and proteomics have identified unexpected dihydrouridylation of mRNAs, greatly expanding the catalog of novel mRNA modifications. These data also implicated dihydrouridylation in meiotic chromosome segregation, protein translation rates, and cell proliferation. Dihydrouridylation of tRNAs and mRNAs are introduced by flavin-dependent dihydrouridine synthases. In this review, we will briefly outline the current knowledge on the distribution of dihydrouridines in the transcriptome, their chemical labeling, and highlight structural and mechanistic aspects regarding the dihydrouridine synthases enzyme family. A special emphasis on important research directions to be addressed will also be discussed. This new entry of dihydrouridine into mRNA modifications has definitely added a new layer of information that controls protein synthesis.
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Affiliation(s)
- Damien Brégeon
- IBPS, Biology of Aging and Adaptation, Sorbonne Université, Paris 75252, France
| | - Ludovic Pecqueur
- Laboratoire de Chimie des Processus Biologiques, CNRS-UMR 8229, Collège De France, Université Pierre et Marie Curie, 11 place Marcelin Berthelot, 75231 Paris, Cedex 05, France
| | - Sabrine Toubdji
- IBPS, Biology of Aging and Adaptation, Sorbonne Université, Paris 75252, France
- Laboratoire de Chimie des Processus Biologiques, CNRS-UMR 8229, Collège De France, Université Pierre et Marie Curie, 11 place Marcelin Berthelot, 75231 Paris, Cedex 05, France
| | - Claudia Sudol
- IBPS, Biology of Aging and Adaptation, Sorbonne Université, Paris 75252, France
- Laboratoire de Chimie des Processus Biologiques, CNRS-UMR 8229, Collège De France, Université Pierre et Marie Curie, 11 place Marcelin Berthelot, 75231 Paris, Cedex 05, France
| | - Murielle Lombard
- Laboratoire de Chimie des Processus Biologiques, CNRS-UMR 8229, Collège De France, Université Pierre et Marie Curie, 11 place Marcelin Berthelot, 75231 Paris, Cedex 05, France
| | - Marc Fontecave
- Laboratoire de Chimie des Processus Biologiques, CNRS-UMR 8229, Collège De France, Université Pierre et Marie Curie, 11 place Marcelin Berthelot, 75231 Paris, Cedex 05, France
| | - Valérie de Crécy-Lagard
- Department of Microbiology and Cell Science, University of Florida, Gainesville, Florida 32611, United States
- Genetics Institute, University of Florida, Gainesville, Florida 32610, United States
| | - Yuri Motorin
- Université de Lorraine, CNRS, INSERM, UMS2008/US40 IBSLor, EpiRNA-Seq Core Facility, Nancy F-54000, France
- Université de Lorraine, CNRS, UMR7365 IMoPA, Nancy F-54000, France
| | - Mark Helm
- Institut für pharmazeutische und biomedizinische Wissenschaften (IPBW), Johannes Gutenberg-Universität, Mainz 55128, Germany
| | - Djemel Hamdane
- Laboratoire de Chimie des Processus Biologiques, CNRS-UMR 8229, Collège De France, Université Pierre et Marie Curie, 11 place Marcelin Berthelot, 75231 Paris, Cedex 05, France
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15
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Motorin Y, Helm M. RNA nucleotide methylation: 2021 update. WILEY INTERDISCIPLINARY REVIEWS. RNA 2022; 13:e1691. [PMID: 34913259 DOI: 10.1002/wrna.1691] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Revised: 07/22/2021] [Accepted: 07/22/2021] [Indexed: 12/14/2022]
Abstract
Among RNA modifications, transfer of methylgroups from the typical cofactor S-adenosyl-l-methionine by methyltransferases (MTases) to RNA is by far the most common reaction. Since our last review about a decade ago, the field has witnessed the re-emergence of mRNA methylation as an important mechanism in gene regulation. Attention has then spread to many other RNA species; all being included into the newly coined concept of the "epitranscriptome." The focus moved from prokaryotes and single cell eukaryotes as model organisms to higher eukaryotes, in particular to mammals. The perception of the field has dramatically changed over the past decade. A previous lack of phenotypes in knockouts in single cell organisms has been replaced by the apparition of MTases in numerous disease models and clinical investigations. Major driving forces of the field include methylation mapping techniques, as well as the characterization of the various MTases, termed "writers." The latter term has spilled over from DNA modification in the neighboring epigenetics field, along with the designations "readers," applied to mediators of biological effects upon specific binding to a methylated RNA. Furthermore "eraser" enzymes effect the newly discovered oxidative removal of methylgroups. A sense of reversibility and dynamics has replaced the older perception of RNA modification as a concrete-cast, irreversible part of RNA maturation. A related concept concerns incompletely methylated residues, which, through permutation of each site, lead to inhomogeneous populations of numerous modivariants. This review recapitulates the major developments of the past decade outlined above, and attempts a prediction of upcoming trends. This article is categorized under: RNA Processing > RNA Editing and Modification.
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Affiliation(s)
- Yuri Motorin
- Université de Lorraine, CNRS, INSERM, UMS2008/US40 IBSLor, EpiRNA-Seq Core Facility, Nancy, France.,Université de Lorraine, CNRS, UMR7365 IMoPA, Nancy, France
| | - Mark Helm
- Institute of Pharmaceutical and Biomedical Sciences, Johannes Gutenberg-Universität, Mainz, Germany
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16
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Zhou JB, Wang ED, Zhou XL. Modifications of the human tRNA anticodon loop and their associations with genetic diseases. Cell Mol Life Sci 2021; 78:7087-7105. [PMID: 34605973 PMCID: PMC11071707 DOI: 10.1007/s00018-021-03948-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 09/07/2021] [Accepted: 09/21/2021] [Indexed: 12/11/2022]
Abstract
Transfer RNAs (tRNAs) harbor the most diverse posttranscriptional modifications. Among such modifications, those in the anticodon loop, either on nucleosides or base groups, compose over half of the identified posttranscriptional modifications. The derivatives of modified nucleotides and the crosstalk of different chemical modifications further add to the structural and functional complexity of tRNAs. These modifications play critical roles in maintaining anticodon loop conformation, wobble base pairing, efficient aminoacylation, and translation speed and fidelity as well as mediating various responses to different stress conditions. Posttranscriptional modifications of tRNA are catalyzed mainly by enzymes and/or cofactors encoded by nuclear genes, whose mutations are firmly connected with diverse human diseases involving genetic nervous system disorders and/or the onset of multisystem failure. In this review, we summarize recent studies about the mechanisms of tRNA modifications occurring at tRNA anticodon loops. In addition, the pathogenesis of related disease-causing mutations at these genes is briefly described.
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Affiliation(s)
- Jing-Bo Zhou
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai, 200031, China
| | - En-Duo Wang
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai, 200031, China.
- School of Life Science and Technology, ShanghaiTech University, 93 Middle Huaxia Road, Shanghai, 201210, China.
| | - Xiao-Long Zhou
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai, 200031, China.
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17
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Li J, Zhu WY, Yang WQ, Li CT, Liu RJ. The occurrence order and cross-talk of different tRNA modifications. SCIENCE CHINA. LIFE SCIENCES 2021; 64:1423-1436. [PMID: 33881742 DOI: 10.1007/s11427-020-1906-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Accepted: 03/02/2021] [Indexed: 06/12/2023]
Abstract
Chemical modifications expand the composition of RNA molecules from four standard nucleosides to over 160 modified nucleosides, which greatly increase the complexity and utility of RNAs. Transfer RNAs (tRNAs) are the most heavily modified cellular RNA molecules and contain the largest variety of modifications. Modification of tRNAs is pivotal for protein synthesis and also precisely regulates the noncanonical functions of tRNAs. Defects in tRNA modifications lead to numerous human diseases. Up to now, more than 100 types of modifications have been found in tRNAs. Intriguingly, some modifications occur widely on all tRNAs, while others only occur on a subgroup of tRNAs or even only a specific tRNA. The modification frequency of each tRNA is approximately 7% to 25%, with 5-20 modification sites present on each tRNA. The occurrence and modulation of tRNA modifications are specifically noticeable as plenty of interplays among different sites and modifications have been discovered. In particular, tRNA modifications are responsive to environmental changes, indicating their dynamic and highly organized nature. In this review, we summarized the known occurrence order, cross-talk, and cooperativity of tRNA modifications.
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Affiliation(s)
- Jing Li
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Wen-Yu Zhu
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Wen-Qing Yang
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Cai-Tao Li
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Ru-Juan Liu
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China.
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18
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Gao Y, Fang J. RNA 5-methylcytosine modification and its emerging role as an epitranscriptomic mark. RNA Biol 2021; 18:117-127. [PMID: 34288807 DOI: 10.1080/15476286.2021.1950993] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
5-methylcytosine (m5C) is identified as an abundant and conserved modification in various RNAs, including tRNAs, mRNAs, rRNAs, and other non-coding RNAs. The application of high-throughput sequencing and mass spectrometry allowed for the detection of m5C at a single-nucleotide resolution and at a global abundance separately; this contributes to a better understanding of m5C modification and its biological functions. m5C modification plays critical roles in diverse aspects of RNA processing, including tRNA stability, rRNA assembly, and mRNA translation. Notably, altered m5C modifications and mutated RNA m5C methyltransferases are associated with diverse pathological processes, such as nervous system disorders and cancers. This review may provide new sights of molecular mechanism and functional importance of m5C modification.
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Affiliation(s)
- Yaqi Gao
- State Key Laboratory for Oncogenes and Related Genes, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, Division of Gastroenterology and Hepatology, Shanghai Institute of Digestive Disease, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Jingyuan Fang
- State Key Laboratory for Oncogenes and Related Genes, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, Division of Gastroenterology and Hepatology, Shanghai Institute of Digestive Disease, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
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19
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Zhang Y, Wang C. Demethyltransferase AlkBH1 substrate diversity and relationship to human diseases. Mol Biol Rep 2021; 48:4747-4756. [PMID: 34046849 DOI: 10.1007/s11033-021-06421-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 05/17/2021] [Indexed: 12/22/2022]
Abstract
AlkBH1 is a member of the AlkB superfamily which are kinds of Fe (II) and α-ketoglutarate (α-KG)-dependent dioxygenases. At present, only demethyltransferases FTO and AlkBH5 have relatively clear substrate studies among these members, the types and mechanisms of substrates catalysis of other members are not clear, especially the demethyltransferase AlkBH1. AlkBH1, as a demethylase, has important functions of reversing DNA methylation and repairing DNA damage. And it has become a promising target for the treatment of many cancers, the regulation of neurological and genetic related diseases. Many scholars have made important discoveries in the diversity of AlkBH1 substrates, but there is no comprehensive summary, which affects the design inhibitor target of AlkBH1. Herein, We are absorbed in the latest progress in the study of AlkBH1 substrate diversity and its relationship with human diseases. Besides, we also discuss future research directions and suggest other studies to reveal the specific catalytic effect of AlkBH1 on cancer substrates.
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Affiliation(s)
- Ying Zhang
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, 510006, Guangdong, China
| | - Caiyan Wang
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, 510006, Guangdong, China.
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20
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Chen YS, Yang WL, Zhao YL, Yang YG. Dynamic transcriptomic m 5 C and its regulatory role in RNA processing. WILEY INTERDISCIPLINARY REVIEWS-RNA 2021; 12:e1639. [PMID: 33438329 DOI: 10.1002/wrna.1639] [Citation(s) in RCA: 96] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Revised: 11/30/2020] [Accepted: 12/04/2020] [Indexed: 12/12/2022]
Abstract
RNA 5-methylcytosine (m5 C) is a prevalent RNA modification in multiple RNA species, including messenger RNAs (mRNAs), transfer RNAs (tRNAs), ribosomal RNAs (rRNAs), and noncoding RNAs (ncRNAs), and broadly distributed from archaea, prokaryotes to eukaryotes. The multiple detecting techniques of m5 C have been developed, such as m5 C-RIP-seq, miCLIP-seq, AZA-IP-seq, RNA-BisSeq, TAWO-seq, and Nanopore sequencing. These high-throughput techniques, combined with corresponding analysis pipeline, provide a precise m5 C landscape contributing to the deciphering of its biological functions. The m5 C modification is distributed along with mRNA and enriched around 5'UTR and 3'UTR, and conserved in tRNAs and rRNAs. It is dynamically regulated by its related enzymes, including methyltransferases (NSUN, DNMT, and TRDMT family members), demethylases (TET families and ALKBH1), and binding proteins (ALYREF and YBX1). So far, accumulative studies have revealed that m5 C participates in a variety of RNA metabolism, including mRNA export, RNA stability, and translation. Depletion of m5 C modification in the organism could cause dysfunction of mitochondria, drawback of stress response, frustration of gametogenesis and embryogenesis, abnormality of neuro and brain development, and has been implicated in cell migration and tumorigenesis. In this review, we provide a comprehensive summary of dynamic regulatory elements of RNA m5 C, including methyltransferases (writers), demethylases (erasers), and binding proteins (readers). We also summarized the related detecting technologies and biological functions of the RNA 5-methylcytosine, and provided future perspectives in m5 C research. This article is categorized under: RNA Processing > RNA Editing and Modification.
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Affiliation(s)
- Yu-Sheng Chen
- Key Laboratory of Genomic and Precision Medicine, Collaborative Innovation Center of Genetics and Development, College of Future Technology, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China.,China National Center For Bioinformation, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Wen-Lan Yang
- Key Laboratory of Genomic and Precision Medicine, Collaborative Innovation Center of Genetics and Development, College of Future Technology, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China.,China National Center For Bioinformation, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China.,Sino-Danish College, University of Chinese Academy of Sciences, Beijing, China
| | - Yong-Liang Zhao
- Key Laboratory of Genomic and Precision Medicine, Collaborative Innovation Center of Genetics and Development, College of Future Technology, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China.,China National Center For Bioinformation, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yun-Gui Yang
- Key Laboratory of Genomic and Precision Medicine, Collaborative Innovation Center of Genetics and Development, College of Future Technology, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China.,China National Center For Bioinformation, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China.,Sino-Danish College, University of Chinese Academy of Sciences, Beijing, China.,Institute of Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China
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21
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Wnuk M, Slipek P, Dziedzic M, Lewinska A. The Roles of Host 5-Methylcytosine RNA Methyltransferases during Viral Infections. Int J Mol Sci 2020; 21:E8176. [PMID: 33142933 PMCID: PMC7663479 DOI: 10.3390/ijms21218176] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Revised: 10/28/2020] [Accepted: 10/28/2020] [Indexed: 12/23/2022] Open
Abstract
Eukaryotic 5-methylcytosine RNA methyltransferases catalyze the transfer of a methyl group to the fifth carbon of a cytosine base in RNA sequences to produce 5-methylcytosine (m5C). m5C RNA methyltransferases play a crucial role in the maintenance of functionality and stability of RNA. Viruses have developed a number of strategies to suppress host innate immunity and ensure efficient transcription and translation for the replication of new virions. One such viral strategy is to use host m5C RNA methyltransferases to modify viral RNA and thus to affect antiviral host responses. Here, we summarize the latest findings concerning the roles of m5C RNA methyltransferases, namely, NOL1/NOP2/SUN domain (NSUN) proteins and DNA methyltransferase 2/tRNA methyltransferase 1 (DNMT2/TRDMT1) during viral infections. Moreover, the use of m5C RNA methyltransferase inhibitors as an antiviral therapy is discussed.
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Affiliation(s)
- Maciej Wnuk
- Department of Biotechnology, Institute of Biology and Biotechnology, University of Rzeszow, 35-310 Rzeszow, Poland; (P.S.); (M.D.)
| | | | | | - Anna Lewinska
- Department of Biotechnology, Institute of Biology and Biotechnology, University of Rzeszow, 35-310 Rzeszow, Poland; (P.S.); (M.D.)
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22
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Abstract
The emergence of genome-wide analyses to interrogate cellular DNA, RNA, and protein content has revolutionized the study of control networks that mediate cellular homeostasis. mRNA translation represents the last step of genetic flow and primarily defines the proteome. Translational regulation is thus critical for gene expression, in particular under nutrient excess or deficiency. Until recently, it was unclear how the global effects of translational control are orchestrated by nutrient signaling pathways. An emerging concept of translational reprogramming addresses how to maintain the expression of specific proteins during nutrient stress by translation of selective mRNAs. In this review, we describe recent advances in our understanding of translational control principles; nutrient-sensing mechanisms; and their dysregulation in human diseases such as diabetes, cancer, and aging. The mechanistic understanding of translational regulation in response to different nutrient conditions may help identify potential dietary and therapeutic targets to improve human health.
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Affiliation(s)
- Xin Erica Shu
- Division of Nutritional Sciences, Cornell University, Ithaca, New York 14853, USA
| | - Robert V. Swanda
- Graduate Field of Biomedical and Biological Sciences, Cornell University, Ithaca, New York 14853, USA
| | - Shu-Bing Qian
- Division of Nutritional Sciences, Cornell University, Ithaca, New York 14853, USA
- Graduate Field of Biomedical and Biological Sciences, Cornell University, Ithaca, New York 14853, USA
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23
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Guo G, Wang H, Shi X, Ye L, Yan K, Chen Z, Zhang H, Jin Z, Xue X. Disease Activity-Associated Alteration of mRNA m 5 C Methylation in CD4 + T Cells of Systemic Lupus Erythematosus. Front Cell Dev Biol 2020; 8:430. [PMID: 32582707 PMCID: PMC7291606 DOI: 10.3389/fcell.2020.00430] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 05/08/2020] [Indexed: 01/17/2023] Open
Abstract
Epigenetic processes including RNA methylation, post-translational modifications, and non-coding RNA expression have been associated with the heritable risks of systemic lupus erythematosus (SLE). In this study, we aimed to explore the dysregulated expression of 5-methylcytosine (m5C) in CD4+ T cells from patients with SLE and the potential function of affected mRNAs in SLE pathogenesis. mRNA methylation profiles were ascertained through chromatography-coupled triple quadrupole mass spectrometry in CD4+ T cells from two pools of patients with SLE exhibiting stable activity, two pools with moderate-to-major activity, and two pools of healthy controls (HCs). Simultaneously, mRNA methylation profiles and expression profiling were performed using RNA-Bis-Seq and RNA-Seq, respectively. Integrated mRNA methylation and mRNA expression bioinformatics analysis was comprehensively performed. mRNA methyltransferase NSUN2 expression was validated in CD4+ T cells from 27 patients with SLE and 28 HCs using real-time polymerase chain reaction and western blot analyses. Hypomethylated-mRNA profiles of NSUN2-knockdown HeLa cells and of CD4+ T cells of patients with SLE were jointly analyzed using bioinformatics. Eleven methylation modifications (including elevated Am, 3′OMeA, m1A, and m6A and decreased Ψ, m3C, m1G, m5U, and t6A levels) were detected in CD4+ T cells of patients with SLE. Additionally, decreased m5C levels, albeit increased number of m5C-containing mRNAs, were observed in CD4+ T cells of patients with SLE compared with that in CD4+ T cells of HCs. m5C site distribution in mRNA transcripts was highly conserved and enriched in mRNA translation initiation sites. In particular, hypermethylated m5C or/and significantly up-regulated genes in SLE were significantly involved in immune-related and inflammatory pathways, including immune system, cytokine signaling pathway, and interferon signaling. Compared to that in HCs, NSUN2 expression was significantly lower in SLE CD4+ T cells. Notably, hypomethylated m5C genes in SLE and in NSUN2-knockdown HeLa cells revealed linkage between eukaryotic translation elongation and termination, and mRNA metabolism. Our study identified novel aberrant m5C mRNAs relevant to critical immune pathways in CD4+ T cells from patients with SLE. These data provide valuable perspectives for future studies of the multifunctionality and post-transcriptional significance of mRNA m5C modification in SLE.
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Affiliation(s)
- Gangqiang Guo
- School of Life Sciences and Technology, Tongji University, Shanghai, China.,Department of Microbiology and Immunology, Institute of Molecular Virology and Immunology, Institute of Tropical Medicine, School of Basic Medical Sciences, Wenzhou Medical University, Wenzhou, China
| | - Huijing Wang
- Kidney Disease Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Xinyu Shi
- Department of Microbiology and Immunology, Institute of Molecular Virology and Immunology, Institute of Tropical Medicine, School of Basic Medical Sciences, Wenzhou Medical University, Wenzhou, China
| | - Lele Ye
- Department of Microbiology and Immunology, Institute of Molecular Virology and Immunology, Institute of Tropical Medicine, School of Basic Medical Sciences, Wenzhou Medical University, Wenzhou, China.,Department of Gynecologic Oncology, Wenzhou Central Hospital, Wenzhou, China
| | - Kejing Yan
- Department of Microbiology and Immunology, Institute of Molecular Virology and Immunology, Institute of Tropical Medicine, School of Basic Medical Sciences, Wenzhou Medical University, Wenzhou, China
| | - Zhiyuan Chen
- Department of Microbiology and Immunology, Institute of Molecular Virology and Immunology, Institute of Tropical Medicine, School of Basic Medical Sciences, Wenzhou Medical University, Wenzhou, China
| | - Huidi Zhang
- Department of Nephrology, The First Affiliated Hospital, Wenzhou Medical University, Wenzhou, China
| | - Zibing Jin
- Laboratory for Stem Cell and Retinal Regeneration, Institute of Stem Cell Research, Division of Ophthalmic Genetics, The Eye Hospital, Wenzhou Medical University, Wenzhou, China
| | - Xiangyang Xue
- Department of Microbiology and Immunology, Institute of Molecular Virology and Immunology, Institute of Tropical Medicine, School of Basic Medical Sciences, Wenzhou Medical University, Wenzhou, China
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24
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Barraud P, Tisné C. To be or not to be modified: Miscellaneous aspects influencing nucleotide modifications in tRNAs. IUBMB Life 2019; 71:1126-1140. [PMID: 30932315 PMCID: PMC6850298 DOI: 10.1002/iub.2041] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Accepted: 03/10/2019] [Indexed: 12/12/2022]
Abstract
Transfer RNAs (tRNAs) are essential components of the cellular protein synthesis machineries, but are also implicated in many roles outside translation. To become functional, tRNAs, initially transcribed as longer precursor tRNAs, undergo a tightly controlled biogenesis process comprising the maturation of their extremities, removal of intronic sequences if present, addition of the 3'-CCA amino-acid accepting sequence, and aminoacylation. In addition, the most impressive feature of tRNA biogenesis consists in the incorporation of a large number of posttranscriptional chemical modifications along its sequence. The chemical nature of these modifications is highly diverse, with more than hundred different modifications identified in tRNAs to date. All functions of tRNAs in cells are controlled and modulated by modifications, making the understanding of the mechanisms that determine and influence nucleotide modifications in tRNAs an essential point in tRNA biology. This review describes the different aspects that determine whether a certain position in a tRNA molecule is modified or not. We describe how sequence and structural determinants, as well as the presence of prior modifications control modification processes. We also describe how environmental factors and cellular stresses influence the level and/or the nature of certain modifications introduced in tRNAs, and report situations where these dynamic modulations of tRNA modification levels are regulated by active demodification processes. © 2019 IUBMB Life, 71(8):1126-1140, 2019.
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Affiliation(s)
- Pierre Barraud
- Expression génétique microbienneInstitut de biologie physico‐chimique (IBPC), UMR 8261, CNRS, Université Paris DiderotParisFrance
| | - Carine Tisné
- Expression génétique microbienneInstitut de biologie physico‐chimique (IBPC), UMR 8261, CNRS, Université Paris DiderotParisFrance
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25
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de Crécy-Lagard V, Boccaletto P, Mangleburg CG, Sharma P, Lowe TM, Leidel SA, Bujnicki JM. Matching tRNA modifications in humans to their known and predicted enzymes. Nucleic Acids Res 2019; 47:2143-2159. [PMID: 30698754 PMCID: PMC6412123 DOI: 10.1093/nar/gkz011] [Citation(s) in RCA: 96] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 12/28/2018] [Accepted: 01/10/2019] [Indexed: 12/25/2022] Open
Abstract
tRNA are post-transcriptionally modified by chemical modifications that affect all aspects of tRNA biology. An increasing number of mutations underlying human genetic diseases map to genes encoding for tRNA modification enzymes. However, our knowledge on human tRNA-modification genes remains fragmentary and the most comprehensive RNA modification database currently contains information on approximately 20% of human cytosolic tRNAs, primarily based on biochemical studies. Recent high-throughput methods such as DM-tRNA-seq now allow annotation of a majority of tRNAs for six specific base modifications. Furthermore, we identified large gaps in knowledge when we predicted all cytosolic and mitochondrial human tRNA modification genes. Only 48% of the candidate cytosolic tRNA modification enzymes have been experimentally validated in mammals (either directly or in a heterologous system). Approximately 23% of the modification genes (cytosolic and mitochondrial combined) remain unknown. We discuss these 'unidentified enzymes' cases in detail and propose candidates whenever possible. Finally, tissue-specific expression analysis shows that modification genes are highly expressed in proliferative tissues like testis and transformed cells, but scarcely in differentiated tissues, with the exception of the cerebellum. Our work provides a comprehensive up to date compilation of human tRNA modifications and their enzymes that can be used as a resource for further studies.
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Affiliation(s)
- Valérie de Crécy-Lagard
- Department of Microbiology and Cell Sciences, University of Florida, Gainesville, FL 32611, USA
- Cancer and Genetic Institute, University of Florida, Gainesville, FL 32611, USA
| | - Pietro Boccaletto
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology, ul. Trojdena 4, 02-109 Warsaw, Poland
| | - Carl G Mangleburg
- Department of Microbiology and Cell Sciences, University of Florida, Gainesville, FL 32611, USA
| | - Puneet Sharma
- Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, 48149 Muenster, Germany
- Cells-in-Motion Cluster of Excellence, University of Muenster, 48149 Muenster, Germany
| | - Todd M Lowe
- Department of Biomolecular Engineering, University of California, Santa Cruz, Santa Cruz, CA 95064, USA
| | - Sebastian A Leidel
- Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, 48149 Muenster, Germany
- Cells-in-Motion Cluster of Excellence, University of Muenster, 48149 Muenster, Germany
- Research Group for RNA Biochemistry, Institute of Chemistry and Biochemistry, University of Bern, 3012 Bern, Switzerland
| | - Janusz M Bujnicki
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology, ul. Trojdena 4, 02-109 Warsaw, Poland
- Institute of Molecular Biology and Biotechnology, Faculty of Biology, Adam Mickiewicz University, ul. Umultowska 89, 61-614 Poznań, Poland
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26
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Lu L, Zhu G, Zeng H, Xu Q, Holzmann K. High tRNA Transferase NSUN2 Gene Expression is Associated with Poor Prognosis in Head and Neck Squamous Carcinoma. Cancer Invest 2018; 36:246-253. [PMID: 29775108 DOI: 10.1080/07357907.2018.1466896] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
NSUN2 is a tRNA methyltransferase and plays an important role in cell development via modifying RNA methylation. We aimed to evaluate the expression of NSUN2 and its prognostic value in HNSCC. Random-effects model of meta-analysis shows 1.99-folds (95% CI: 1.89-2.09) upregulation of NSUN2 expression in HNSCC versus normal tissues. Patients with high NSUN2 levels had approximately 22 months shorter overall survival, and had a higher mortality risk than those with low one (p-trend = 0.020). In conclusion, NSUN2 is a potential independent prognostic marker and may be a potential therapeutic target in HNSCC.
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Affiliation(s)
- Lingeng Lu
- a Department of Chronic Disease Epidemiology , School of Public Health, School of Medicine, Center for Biomedical Data Science, Yale Cancer Center, Yale University , New Haven , Connecticut , USA
| | - Gongjian Zhu
- b Gansu Provincial Academy of Medical Science, Gansu Provincial Cancer Hospital , Lanzhou , China
| | - Hongmei Zeng
- c National Office for Cancer Prevention and Control, Cancer Hospital, Chinese Academy of Medical Sciences/National Cancer Center , Beijing , China
| | - Qian Xu
- d Key Laboratory of Environmental Medicine Engineering, Ministry of Education , School of Public Health, Southeast University , Nanjing , China
| | - Klaus Holzmann
- e Division of Cancer Research, Department of Medicine I , Comprehensive Cancer Center, Medical University of Vienna , Austria
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27
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Liu RJ, Long T, Li J, Li H, Wang ED. Structural basis for substrate binding and catalytic mechanism of a human RNA:m5C methyltransferase NSun6. Nucleic Acids Res 2017; 45:6684-6697. [PMID: 28531330 PMCID: PMC5499824 DOI: 10.1093/nar/gkx473] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 05/12/2017] [Indexed: 12/20/2022] Open
Abstract
5-methylcytosine (m5C) modifications of RNA are ubiquitous in nature and play important roles in many biological processes such as protein translational regulation, RNA processing and stress response. Aberrant expressions of RNA:m5C methyltransferases are closely associated with various human diseases including cancers. However, no structural information for RNA-bound RNA:m5C methyltransferase was available until now, hindering elucidation of the catalytic mechanism behind RNA:m5C methylation. Here, we have solved the structures of NSun6, a human tRNA:m5C methyltransferase, in the apo form and in complex with a full-length tRNA substrate. These structures show a non-canonical conformation of the bound tRNA, rendering the base moiety of the target cytosine accessible to the enzyme for methylation. Further biochemical assays reveal the critical, but distinct, roles of two conserved cysteine residues for the RNA:m5C methylation. Collectively, for the first time, we have solved the complex structure of a RNA:m5C methyltransferase and addressed the catalytic mechanism of the RNA:m5C methyltransferase family, which may allow for structure-based drug design toward RNA:m5C methyltransferase–related diseases.
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Affiliation(s)
- Ru-Juan Liu
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, P. R. China
| | - Tao Long
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, P. R. China.,University of Chinese Academy of Sciences, Beijing 100039, P. R. China
| | - Jing Li
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, P. R. China.,University of Chinese Academy of Sciences, Beijing 100039, P. R. China
| | - Hao Li
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, P. R. China.,University of Chinese Academy of Sciences, Beijing 100039, P. R. China
| | - En-Duo Wang
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, P. R. China.,University of Chinese Academy of Sciences, Beijing 100039, P. R. China.,School of Life Science and Technology, ShanghaiTech University, 100 Haike Road, Shanghai 201210, P. R. China
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28
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Kossinova OA, Gopanenko AV, Tamkovich SN, Krasheninina OA, Tupikin AE, Kiseleva E, Yanshina DD, Malygin AA, Ven'yaminova AG, Kabilov MR, Karpova GG. Cytosolic YB-1 and NSUN2 are the only proteins recognizing specific motifs present in mRNAs enriched in exosomes. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2017; 1865:664-673. [PMID: 28341602 DOI: 10.1016/j.bbapap.2017.03.010] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 03/16/2017] [Accepted: 03/20/2017] [Indexed: 12/27/2022]
Abstract
Exosomes, membranous vesicles secreted by various cells, are involved in intercellular communication and carry vast repertoires of RNAs and proteins. Processes mediating RNA sorting into exosomes are currently poorly understood. Using bioinformatics approaches, three structural motifs ACCAGCCU, CAGUGAGC and UAAUCCCA have been discovered as enriched in exosomal mRNAs and long noncoding RNAs. Here, utilizing short RNA hairpins, each containing one of the motifs, in a pull-down assay of cytosolic extract of human embryonic kidney 293 (HEK293) cells, we prove that multifunctional RNA-binding protein YB-1 specifically interacts with all three motifs, whereas methyltransferase NSUN2 recognizes only the motif CAGUGAGC. RNA hairpins other than those mentioned above pull out neither YB-1 nor NSUN2. Both these proteins are found in exosomes secreted by HEK293 cells. YB-1 for all that is detected as a form having a slightly higher electrophoretic mobility than that of YB-1 associated with the above RNA hairpins, assuming changes in posttranslational modifications of the protein during its transfer from cytoplasm into exosomes. Next generation sequencing of total exosomal RNA (eRNA) reveals a large representative set of RNA species, including mRNAs containing the above-mentioned motifs. The degree of enrichment in exosomes with this kind of mRNAs strongly depends on the locations of eRNA-specific motifs within the mRNA sequences. Altogether, our findings point to YB-1 and NSUN2 as possible mediators of the process of transfer of specific mRNAs into exosomes, allowing us to speculate on an involvement of these proteins in the mRNA sorting via the recognition of the above motifs.
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Affiliation(s)
- Olga A Kossinova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Prospekt Lavrentieva 8, Novosibirsk 630090, Russia
| | - Alexander V Gopanenko
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Prospekt Lavrentieva 8, Novosibirsk 630090, Russia; Department of Molecular Biology, Novosibirsk State University, Novosibirsk 630090, Russia
| | - Svetlana N Tamkovich
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Prospekt Lavrentieva 8, Novosibirsk 630090, Russia; Department of Molecular Biology, Novosibirsk State University, Novosibirsk 630090, Russia
| | - Olga A Krasheninina
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Prospekt Lavrentieva 8, Novosibirsk 630090, Russia
| | - Alexey E Tupikin
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Prospekt Lavrentieva 8, Novosibirsk 630090, Russia
| | - Elena Kiseleva
- Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Prospekt Lavrentieva 10, Novosibirsk 630090, Russia
| | - Darya D Yanshina
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Prospekt Lavrentieva 8, Novosibirsk 630090, Russia
| | - Alexey A Malygin
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Prospekt Lavrentieva 8, Novosibirsk 630090, Russia; Department of Molecular Biology, Novosibirsk State University, Novosibirsk 630090, Russia
| | - Alia G Ven'yaminova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Prospekt Lavrentieva 8, Novosibirsk 630090, Russia
| | - Marsel R Kabilov
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Prospekt Lavrentieva 8, Novosibirsk 630090, Russia
| | - Galina G Karpova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Prospekt Lavrentieva 8, Novosibirsk 630090, Russia; Department of Molecular Biology, Novosibirsk State University, Novosibirsk 630090, Russia.
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29
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Väre VYP, Eruysal ER, Narendran A, Sarachan KL, Agris PF. Chemical and Conformational Diversity of Modified Nucleosides Affects tRNA Structure and Function. Biomolecules 2017; 7:E29. [PMID: 28300792 PMCID: PMC5372741 DOI: 10.3390/biom7010029] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 03/06/2017] [Accepted: 03/06/2017] [Indexed: 12/21/2022] Open
Abstract
RNAs are central to all gene expression through the control of protein synthesis. Four major nucleosides, adenosine, guanosine, cytidine and uridine, compose RNAs and provide sequence variation, but are limited in contributions to structural variation as well as distinct chemical properties. The ability of RNAs to play multiple roles in cellular metabolism is made possible by extensive variation in length, conformational dynamics, and the over 100 post-transcriptional modifications. There are several reviews of the biochemical pathways leading to RNA modification, but the physicochemical nature of modified nucleosides and how they facilitate RNA function is of keen interest, particularly with regard to the contributions of modified nucleosides. Transfer RNAs (tRNAs) are the most extensively modified RNAs. The diversity of modifications provide versatility to the chemical and structural environments. The added chemistry, conformation and dynamics of modified nucleosides occurring at the termini of stems in tRNA's cloverleaf secondary structure affect the global three-dimensional conformation, produce unique recognition determinants for macromolecules to recognize tRNAs, and affect the accurate and efficient decoding ability of tRNAs. This review will discuss the impact of specific chemical moieties on the structure, stability, electrochemical properties, and function of tRNAs.
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Affiliation(s)
- Ville Y P Väre
- The RNA Institute, Departments of Biological Sciences and Chemistry, University at Albany, State University of New York, Albany, NY 12222, USA.
| | - Emily R Eruysal
- The RNA Institute, Departments of Biological Sciences and Chemistry, University at Albany, State University of New York, Albany, NY 12222, USA.
| | - Amithi Narendran
- The RNA Institute, Departments of Biological Sciences and Chemistry, University at Albany, State University of New York, Albany, NY 12222, USA.
| | - Kathryn L Sarachan
- The RNA Institute, Departments of Biological Sciences and Chemistry, University at Albany, State University of New York, Albany, NY 12222, USA.
| | - Paul F Agris
- The RNA Institute, Departments of Biological Sciences and Chemistry, University at Albany, State University of New York, Albany, NY 12222, USA.
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30
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David R, Burgess A, Parker B, Li J, Pulsford K, Sibbritt T, Preiss T, Searle IR. Transcriptome-Wide Mapping of RNA 5-Methylcytosine in Arabidopsis mRNAs and Noncoding RNAs. THE PLANT CELL 2017; 29:445-460. [PMID: 28062751 PMCID: PMC5385953 DOI: 10.1105/tpc.16.00751] [Citation(s) in RCA: 158] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 12/08/2016] [Accepted: 01/02/2017] [Indexed: 05/20/2023]
Abstract
Posttranscriptional methylation of RNA cytosine residues to 5-methylcytosine (m5C) is an important modification with diverse roles, such as regulating stress responses, stem cell proliferation, and RNA metabolism. Here, we used RNA bisulfite sequencing for transcriptome-wide quantitative mapping of m5C in the model plant Arabidopsis thaliana We discovered more than a thousand m5C sites in Arabidopsis mRNAs, long noncoding RNAs, and other noncoding RNAs across three tissue types (siliques, seedling shoots, and roots) and validated a number of these sites. Quantitative differences in methylated sites between these three tissues suggest tissue-specific regulation of m5C. Perturbing the RNA m5C methyltransferase TRM4B resulted in the loss of m5C sites on mRNAs and noncoding RNAs and reduced the stability of tRNAAsp(GTC) We also demonstrate the importance of m5C in plant development, as trm4b mutants have shorter primary roots than the wild type due to reduced cell division in the root apical meristem. In addition, trm4b mutants show increased sensitivity to oxidative stress. Finally, we provide insights into the targeting mechanism of TRM4B by demonstrating that a 50-nucleotide sequence flanking m5C C3349 in MAIGO5 mRNA is sufficient to confer methylation of a transgene reporter in Nicotiana benthamiana.
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Affiliation(s)
- Rakesh David
- School of Biological Sciences, The University of Adelaide, The University of Adelaide and Shanghai Jiao Tong University Joint International Centre for Agriculture and Health, Adelaide, South Australia 5005, Australia
| | - Alice Burgess
- School of Biological Sciences, The University of Adelaide, The University of Adelaide and Shanghai Jiao Tong University Joint International Centre for Agriculture and Health, Adelaide, South Australia 5005, Australia
| | - Brian Parker
- Department of Biology, New York University, New York, New York 1003-6688
- EMBL-Australia Collaborating Group, Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Jun Li
- School of Biological Sciences, The University of Adelaide, The University of Adelaide and Shanghai Jiao Tong University Joint International Centre for Agriculture and Health, Adelaide, South Australia 5005, Australia
| | - Kalinya Pulsford
- School of Biological Sciences, The University of Adelaide, The University of Adelaide and Shanghai Jiao Tong University Joint International Centre for Agriculture and Health, Adelaide, South Australia 5005, Australia
| | - Tennille Sibbritt
- EMBL-Australia Collaborating Group, Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Thomas Preiss
- EMBL-Australia Collaborating Group, Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
- Victor Chang Cardiac Research Institute, Sydney, New South Wales 2010, Australia
| | - Iain Robert Searle
- School of Biological Sciences, The University of Adelaide, The University of Adelaide and Shanghai Jiao Tong University Joint International Centre for Agriculture and Health, Adelaide, South Australia 5005, Australia
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31
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David R, Burgess A, Parker B, Li J, Pulsford K, Sibbritt T, Preiss T, Searle IR. Transcriptome-Wide Mapping of RNA 5-Methylcytosine in Arabidopsis mRNAs and Noncoding RNAs. THE PLANT CELL 2017. [PMID: 28062751 DOI: 10.6084/m9.figshare.3408193.v2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Posttranscriptional methylation of RNA cytosine residues to 5-methylcytosine (m5C) is an important modification with diverse roles, such as regulating stress responses, stem cell proliferation, and RNA metabolism. Here, we used RNA bisulfite sequencing for transcriptome-wide quantitative mapping of m5C in the model plant Arabidopsis thaliana We discovered more than a thousand m5C sites in Arabidopsis mRNAs, long noncoding RNAs, and other noncoding RNAs across three tissue types (siliques, seedling shoots, and roots) and validated a number of these sites. Quantitative differences in methylated sites between these three tissues suggest tissue-specific regulation of m5C. Perturbing the RNA m5C methyltransferase TRM4B resulted in the loss of m5C sites on mRNAs and noncoding RNAs and reduced the stability of tRNAAsp(GTC) We also demonstrate the importance of m5C in plant development, as trm4b mutants have shorter primary roots than the wild type due to reduced cell division in the root apical meristem. In addition, trm4b mutants show increased sensitivity to oxidative stress. Finally, we provide insights into the targeting mechanism of TRM4B by demonstrating that a 50-nucleotide sequence flanking m5C C3349 in MAIGO5 mRNA is sufficient to confer methylation of a transgene reporter in Nicotiana benthamiana.
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Affiliation(s)
- Rakesh David
- School of Biological Sciences, The University of Adelaide, The University of Adelaide and Shanghai Jiao Tong University Joint International Centre for Agriculture and Health, Adelaide, South Australia 5005, Australia
| | - Alice Burgess
- School of Biological Sciences, The University of Adelaide, The University of Adelaide and Shanghai Jiao Tong University Joint International Centre for Agriculture and Health, Adelaide, South Australia 5005, Australia
| | - Brian Parker
- Department of Biology, New York University, New York, New York 1003-6688
- EMBL-Australia Collaborating Group, Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Jun Li
- School of Biological Sciences, The University of Adelaide, The University of Adelaide and Shanghai Jiao Tong University Joint International Centre for Agriculture and Health, Adelaide, South Australia 5005, Australia
| | - Kalinya Pulsford
- School of Biological Sciences, The University of Adelaide, The University of Adelaide and Shanghai Jiao Tong University Joint International Centre for Agriculture and Health, Adelaide, South Australia 5005, Australia
| | - Tennille Sibbritt
- EMBL-Australia Collaborating Group, Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Thomas Preiss
- EMBL-Australia Collaborating Group, Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
- Victor Chang Cardiac Research Institute, Sydney, New South Wales 2010, Australia
| | - Iain Robert Searle
- School of Biological Sciences, The University of Adelaide, The University of Adelaide and Shanghai Jiao Tong University Joint International Centre for Agriculture and Health, Adelaide, South Australia 5005, Australia
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Rana AK, Ankri S. Reviving the RNA World: An Insight into the Appearance of RNA Methyltransferases. Front Genet 2016; 7:99. [PMID: 27375676 PMCID: PMC4893491 DOI: 10.3389/fgene.2016.00099] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 05/23/2016] [Indexed: 12/13/2022] Open
Abstract
RNA, the earliest genetic and catalytic molecule, has a relatively delicate and labile chemical structure, when compared to DNA. It is prone to be damaged by alkali, heat, nucleases, or stress conditions. One mechanism to protect RNA or DNA from damage is through site-specific methylation. Here, we propose that RNA methylation began prior to DNA methylation in the early forms of life evolving on Earth. In this article, the biochemical properties of some RNA methyltransferases (MTases), such as 2′-O-MTases (Rlml/RlmN), spOUT MTases and the NSun2 MTases are dissected for the insight they provide on the transition from an RNA world to our present RNA/DNA/protein world.
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Affiliation(s)
- Ajay K Rana
- Division of Biology, State Forensic Science Laboratory, Ministry of Home Affairs, Government of Jharkhand Ranchi, India
| | - Serge Ankri
- Department of Molecular Microbiology, The Ruth and Bruce Rappaport Faculty of Medicine, Technion Israel Institute of Technology Haifa, Israel
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Abstract
tRNA molecules undergo extensive post-transcriptional processing to generate the mature functional tRNA species that are essential for translation in all organisms. These processing steps include the introduction of numerous specific chemical modifications to nucleotide bases and sugars; among these modifications, methylation reactions are by far the most abundant. The tRNA methyltransferases comprise a diverse enzyme superfamily, including members of multiple structural classes that appear to have arisen independently during evolution. Even among closely related family members, examples of unusual substrate specificity and chemistry have been observed. Here we review recent advances in tRNA methyltransferase mechanism and function with a particular emphasis on discoveries of alternative substrate specificities and chemistry associated with some methyltransferases. Although the molecular function for a specific tRNA methylation may not always be clear, mutations in tRNA methyltransferases have been increasingly associated with human disease. The impact of tRNA methylation on human biology is also discussed.
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Affiliation(s)
- William E Swinehart
- a Center for RNA Biology and Department of Chemistry and Biochemistry ; Ohio State University ; Columbus , OH USA
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Landmarks in the Evolution of (t)-RNAs from the Origin of Life up to Their Present Role in Human Cognition. Life (Basel) 2015; 6:life6010001. [PMID: 26703740 PMCID: PMC4810232 DOI: 10.3390/life6010001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 12/07/2015] [Accepted: 12/15/2015] [Indexed: 01/28/2023] Open
Abstract
How could modern life have evolved? The answer to that question still remains unclear. However, evidence is growing that, since the origin of life, RNA could have played an important role throughout evolution, right up to the development of complex organisms and even highly sophisticated features such as human cognition. RNA mediated RNA-aminoacylation can be seen as a first landmark on the path from the RNA world to modern DNA- and protein-based life. Likewise, the generation of the RNA modifications that can be found in various RNA species today may already have started in the RNA world, where such modifications most likely entailed functional advantages. This association of modification patterns with functional features was apparently maintained throughout the further course of evolution, and particularly tRNAs can now be seen as paradigms for the developing interdependence between structure, modification and function. It is in this spirit that this review highlights important stepping stones of the development of (t)RNAs and their modifications (including aminoacylation) from the ancient RNA world up until their present role in the development and maintenance of human cognition. The latter can be seen as a high point of evolution at its present stage, and the susceptibility of cognitive features to even small alterations in the proper structure and functioning of tRNAs underscores the evolutionary relevance of this RNA species.
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Burgess AL, David R, Searle IR. Conservation of tRNA and rRNA 5-methylcytosine in the kingdom Plantae. BMC PLANT BIOLOGY 2015; 15:199. [PMID: 26268215 PMCID: PMC4535395 DOI: 10.1186/s12870-015-0580-8] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2015] [Accepted: 07/24/2015] [Indexed: 05/18/2023]
Abstract
BACKGROUND Post-transcriptional methylation of RNA cytosine residues to 5-methylcytosine (m(5)C) is an important modification that regulates RNA metabolism and occurs in both eukaryotes and prokaryotes. Yet, to date, no transcriptome-wide identification of m(5)C sites has been undertaken in plants. Plants provide a unique comparative system for investigating the origin and evolution of m(5)C as they contain three different genomes, the nucleus, mitochondria and chloroplast. Here we use bisulfite conversion of RNA combined with high-throughput IIlumina sequencing (RBS-seq) to identify single-nucleotide resolution of m(5)C sites in non-coding ribosomal RNAs and transfer RNAs of all three sub-cellular transcriptomes across six diverse species that included, the single-celled algae Nannochloropsis oculata, the macro algae Caulerpa taxifolia and multi-cellular higher plants Arabidopsis thaliana, Brassica rapa, Triticum durum and Ginkgo biloba. RESULTS Using the plant model Arabidopsis thaliana, we identified a total of 39 highly methylated m(5)C sites in predicted structural positions of nuclear tRNAs and 7 m(5)C sites in rRNAs from nuclear, chloroplast and mitochondrial transcriptomes. Both the nucleotide position and percent methylation of tRNAs and rRNAs m(5)C sites were conserved across all species analysed, from single celled algae N. oculata to multicellular plants. Interestingly the mitochondrial and chloroplast encoded tRNAs were devoid of m(5)C in A. thaliana and this is generally conserved across Plantae. This suggests independent evolution of organelle methylation in animals and plants, as animal mitochondrial tRNAs have m(5)C sites. Here we characterize 5 members of the RNA 5-methylcytosine family in Arabidopsis and extend the functional characterization of TRDMT1 and NOP2A/OLI2. We demonstrate that nuclear tRNA methylation requires two evolutionarily conserved methyltransferases, TRDMT1 and TRM4B. trdmt1 trm4b double mutants are hypersensitive to the antibiotic hygromycin B, demonstrating the function of tRNA methylation in regulating translation. Additionally we demonstrate that nuclear large subunit 25S rRNA methylation requires the conserved RNA methyltransferase NSUN5. Our results also suggest functional redundancy of at least two of the NOP2 paralogs in Arabidopsis. CONCLUSIONS Our data demonstrates widespread occurrence and conservation of non-coding RNA methylation in the kingdom Plantae, suggesting important and highly conserved roles of this post-transcriptional modification.
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Affiliation(s)
- Alice Louise Burgess
- School of Biological Sciences, The University of Adelaide, Adelaide, South Australia, 5005, Australia.
- School of Agriculture, Food and Wine, The Waite Research Institute, The University of Adelaide, Adelaide, South Australia, 5005, Australia.
| | - Rakesh David
- School of Biological Sciences, The University of Adelaide, Adelaide, South Australia, 5005, Australia.
- School of Agriculture, Food and Wine, The Waite Research Institute, The University of Adelaide, Adelaide, South Australia, 5005, Australia.
| | - Iain Robert Searle
- School of Biological Sciences, The University of Adelaide, Adelaide, South Australia, 5005, Australia.
- School of Agriculture, Food and Wine, The Waite Research Institute, The University of Adelaide, Adelaide, South Australia, 5005, Australia.
- The University of Adelaide and Shanghai Jiao Tong University Joint International Centre for Agriculture and Health, Adelaide, Australia.
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Bourgeois G, Ney M, Gaspar I, Aigueperse C, Schaefer M, Kellner S, Helm M, Motorin Y. Eukaryotic rRNA Modification by Yeast 5-Methylcytosine-Methyltransferases and Human Proliferation-Associated Antigen p120. PLoS One 2015. [PMID: 26196125 PMCID: PMC4510066 DOI: 10.1371/journal.pone.0133321] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Modified nucleotide 5-methylcytosine (m5C) is frequently present in various eukaryotic RNAs, including tRNAs, rRNAs and in other non-coding RNAs, as well as in mRNAs. RNA:m5C-methyltranferases (MTases) Nop2 from S. cerevisiae and human proliferation-associated nucleolar antigen p120 are both members of a protein family called Nop2/NSUN/NOL1. Protein p120 is well-known as a tumor marker which is over-expressed in various cancer tissues. Using a combination of RNA bisulfite sequencing and HPLC-MS/MS analysis, we demonstrated here that p120 displays an RNA:m5C- MTase activity, which restores m5C formation at position 2870 in domain V of 25S rRNA in a nop2Δ yeast strain. We also confirm that yeast proteins Nop2p and Rcm1p catalyze the formation of m5C in domains V and IV, respectively. In addition, we do not find any evidence of m5C residues in yeast 18S rRNA. We also performed functional complementation of Nop2-deficient yeasts by human p120 and studied the importance of different sequence and structural domains of Nop2 and p120 for yeast growth and m5C-MTase activity. Chimeric protein formed by Nop2 and p120 fragments revealed the importance of Nop2 N-terminal domain for correct protein localization and its cellular function. We also validated that the presence of Nop2, rather than the m5C modification in rRNA itself, is required for pre-rRNA processing. Our results corroborate that Nop2 belongs to the large family of pre-ribosomal proteins and possesses two related functions in pre-rRNA processing: as an essential factor for cleavages and m5C:RNA:modification. These results support the notion of quality control during ribosome synthesis by such modification enzymes.
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Affiliation(s)
- Gabrielle Bourgeois
- Laboratoire IMoPA, UMR 7365 UL-CNRS, BioPole de UL, Vandoeuvre-les-Nancy, France
| | - Michel Ney
- Laboratoire IMoPA, UMR 7365 UL-CNRS, BioPole de UL, Vandoeuvre-les-Nancy, France
| | - Imre Gaspar
- EMBL Heidelberg, Meyerhofstraße 1, 69117, Heidelberg, Germany
| | | | - Matthias Schaefer
- Division of Epigenetics, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Stefanie Kellner
- Institute of Pharmacy and Biochemistry, Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Mark Helm
- Institute of Pharmacy and Biochemistry, Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Yuri Motorin
- Laboratoire IMoPA, UMR 7365 UL-CNRS, BioPole de UL, Vandoeuvre-les-Nancy, France
- * E-mail:
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Moon HJ, Redman KL. Trm4 and Nsun2 RNA:m5C Methyltransferases Form Metabolite-Dependent, Covalent Adducts with Previously Methylated RNA. Biochemistry 2014; 53:7132-44. [DOI: 10.1021/bi500882b] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Haley J. Moon
- Indiana University School of Medicine-Fort Wayne, 2101 Coliseum Boulevard East, Fort Wayne, Indiana 46805, United States
| | - Kent L. Redman
- Indiana University School of Medicine-Fort Wayne, 2101 Coliseum Boulevard East, Fort Wayne, Indiana 46805, United States
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Okamoto M, Fujiwara M, Hori M, Okada K, Yazama F, Konishi H, Xiao Y, Qi G, Shimamoto F, Ota T, Temme A, Tatsuka M. tRNA modifying enzymes, NSUN2 and METTL1, determine sensitivity to 5-fluorouracil in HeLa cells. PLoS Genet 2014; 10:e1004639. [PMID: 25233213 PMCID: PMC4169382 DOI: 10.1371/journal.pgen.1004639] [Citation(s) in RCA: 101] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2014] [Accepted: 07/30/2014] [Indexed: 11/18/2022] Open
Abstract
Nonessential tRNA modifications by methyltransferases are evolutionarily conserved and have been reported to stabilize mature tRNA molecules and prevent rapid tRNA decay (RTD). The tRNA modifying enzymes, NSUN2 and METTL1, are mammalian orthologs of yeast Trm4 and Trm8, which are required for protecting tRNA against RTD. A simultaneous overexpression of NSUN2 and METTL1 is widely observed among human cancers suggesting that targeting of both proteins provides a novel powerful strategy for cancer chemotherapy. Here, we show that combined knockdown of NSUN2 and METTL1 in HeLa cells drastically potentiate sensitivity of cells to 5-fluorouracil (5-FU) whereas heat stress of cells revealed no effects. Since NSUN2 and METTL1 are phosphorylated by Aurora-B and Akt, respectively, and their tRNA modifying activities are suppressed by phosphorylation, overexpression of constitutively dephosphorylated forms of both methyltransferases is able to suppress 5-FU sensitivity. Thus, NSUN2 and METTL1 are implicated in 5-FU sensitivity in HeLa cells. Interfering with methylation of tRNAs might provide a promising rationale to improve 5-FU chemotherapy of cancer. The cellular mechanisms for sensing and responding to stress on nucleic acid metabolism or to genotoxic stress are the fundamental and ancient evolutionary biological activities with conserved and diverse biological functions. In yeast, hypomodified mature tRNA species are rapidly decayed under heat stress by the RTD pathway. Yet, it has been shown that tRNA-specific methyltransferases Trm4 and Trm8 protect from tRNA decay. 5-FU, a pyrimidine analog used for cancer treatment, is generally known to act as a thymidylate synthase inhibitor although other ways for the mechanisms of action are suggested. We studied NSUN2 and METTL1, the human orthologs of Trm4 and Trm8 in yeast, and demonstrated that these RTD-related tRNA modifying enzymes are involved in 5-FU sensitivity in cervical cancer HeLa cells. We conclude that the evolutionarily conserved regulation of tRNA modifications is a potential mechanism of chemotherapy resistance in cancer cells.
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Affiliation(s)
- Mayumi Okamoto
- Department of Life Sciences, Faculty of Life and Environmental Sciences, Prefectural University of Hiroshima, Shoubara, Hiroshima, Japan
| | - Mamoru Fujiwara
- Department of Life Sciences, Faculty of Life and Environmental Sciences, Prefectural University of Hiroshima, Shoubara, Hiroshima, Japan
| | - Masato Hori
- Department of Life Sciences, Faculty of Life and Environmental Sciences, Prefectural University of Hiroshima, Shoubara, Hiroshima, Japan
| | - Kaoru Okada
- Department of Life Sciences, Faculty of Life and Environmental Sciences, Prefectural University of Hiroshima, Shoubara, Hiroshima, Japan
| | - Futoshi Yazama
- Department of Life Sciences, Faculty of Life and Environmental Sciences, Prefectural University of Hiroshima, Shoubara, Hiroshima, Japan
| | - Hiroaki Konishi
- Department of Life Sciences, Faculty of Life and Environmental Sciences, Prefectural University of Hiroshima, Shoubara, Hiroshima, Japan
| | - Yegui Xiao
- Department of Management Information Systems, Faculty of Management and Information System, Prefectural University of Hiroshima, Minami-ku, Hiroshima, Japan
| | - Guangying Qi
- Department of Health Sciences, Faculty of Human Culture and Science, Prefectural University of Hiroshima, Minami-ku, Hiroshima, Japan
| | - Fumio Shimamoto
- Department of Health Sciences, Faculty of Human Culture and Science, Prefectural University of Hiroshima, Minami-ku, Hiroshima, Japan
| | - Takahide Ota
- Department of Life Science, Medical Research Institute, Kanazawa Medical University, Uchinada, Ishikawa, Japan
| | - Achim Temme
- Department of Neurosurgery, University Hospital Carl Gustav Carus, Technical University Dresden, Dresden, Germany
| | - Masaaki Tatsuka
- Department of Life Sciences, Faculty of Life and Environmental Sciences, Prefectural University of Hiroshima, Shoubara, Hiroshima, Japan
- * E-mail:
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Hori H. Methylated nucleosides in tRNA and tRNA methyltransferases. Front Genet 2014; 5:144. [PMID: 24904644 PMCID: PMC4033218 DOI: 10.3389/fgene.2014.00144] [Citation(s) in RCA: 141] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Accepted: 05/04/2014] [Indexed: 12/26/2022] Open
Abstract
To date, more than 90 modified nucleosides have been found in tRNA and the biosynthetic pathways of the majority of tRNA modifications include a methylation step(s). Recent studies of the biosynthetic pathways have demonstrated that the availability of methyl group donors for the methylation in tRNA is important for correct and efficient protein synthesis. In this review, I focus on the methylated nucleosides and tRNA methyltransferases. The primary functions of tRNA methylations are linked to the different steps of protein synthesis, such as the stabilization of tRNA structure, reinforcement of the codon-anticodon interaction, regulation of wobble base pairing, and prevention of frameshift errors. However, beyond these basic functions, recent studies have demonstrated that tRNA methylations are also involved in the RNA quality control system and regulation of tRNA localization in the cell. In a thermophilic eubacterium, tRNA modifications and the modification enzymes form a network that responses to temperature changes. Furthermore, several modifications are involved in genetic diseases, infections, and the immune response. Moreover, structural, biochemical, and bioinformatics studies of tRNA methyltransferases have been clarifying the details of tRNA methyltransferases and have enabled these enzymes to be classified. In the final section, the evolution of modification enzymes is discussed.
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Affiliation(s)
- Hiroyuki Hori
- Department of Materials Science and Biotechnology, Applied Chemistry, Graduate School of Science and Engineering, Ehime University Matsuyama, Japan
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40
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Sharma S, Yang J, Watzinger P, Kötter P, Entian KD. Yeast Nop2 and Rcm1 methylate C2870 and C2278 of the 25S rRNA, respectively. Nucleic Acids Res 2013; 41:9062-76. [PMID: 23913415 PMCID: PMC3799443 DOI: 10.1093/nar/gkt679] [Citation(s) in RCA: 145] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Yeast 25S rRNA was reported to contain a single cytosine methylation (m5C). In the present study using a combination of RP-HPLC, mung bean nuclease assay and rRNA mutagenesis, we discovered that instead of one, yeast contains two m5C residues at position 2278 and 2870. Furthermore, we identified and characterized two putative methyltransferases, Rcm1 and Nop2 to be responsible for these two cytosine methylations, respectively. Both proteins are highly conserved, which correlates with the presence of two m5C residues at identical positions in higher eukaryotes, including humans. The human homolog of yeast Nop2, p120 has been discovered to be upregulated in various cancer tissues, whereas the human homolog of Rcm1, NSUN5 is completely deleted in the William's-Beuren Syndrome. The substrates and function of both human homologs remained unknown. In the present study, we also provide insights into the significance of these two m5C residues. The loss of m5C2278 results in anisomycin hypersensitivity, whereas the loss of m5C2870 affects ribosome synthesis and processing. Establishing the locations and enzymes in yeast will not only help identifying the function of their homologs in higher organisms, but will also enable understanding the role of these modifications in ribosome function and architecture.
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Affiliation(s)
- Sunny Sharma
- Department of Molecular Genetics & Cellular Microbiology, Institute of Molecular Biosciences, Goethe University, Max-von-Laue Str. 9, 60438 Frankfurt/M, Germany
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Chi L, Delgado-Olguín P. Expression of NOL1/NOP2/sun domain (Nsun) RNA methyltransferase family genes in early mouse embryogenesis. Gene Expr Patterns 2013; 13:319-27. [PMID: 23816522 DOI: 10.1016/j.gep.2013.06.003] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Revised: 06/18/2013] [Accepted: 06/20/2013] [Indexed: 01/08/2023]
Abstract
The NOL1/NOP2/sun domain-containing genes encode the RNA methyltransferases Nsun2, 3, 4, 5, 6 and 7. Methylated RNA pervades the transcriptome, yet the function of RNA methyltransferases is poorly understood. Nsun2 and Nsun4 participate in cell proliferation and differentiation, protein biosynthesis and cancer. In addition, Nsun2 and Nsun7 dysfunction might cause intellectual disability and male sterility, respectively. The functions of Nsun3, Nsun5 and Nsun6 are unknown. Given the widespread distribution of RNA methylation, it is possible that Nsun genes participate in a broader range of relevant biological processes including the regulation of embryogenesis. Here, we describe the expression pattern of Nsun genes during mouse embryo development. In situ hybridization showed developmentally regulated Nsun gene expression. Nsun genes express broadly during gastrulation, but enrich in specific tissues as embryogenesis proceeds. Nsun transcripts enrich in the developing brain, consistent with proposed functions in neurocognitive development. In addition, Nsun transcripts enrich in the developing ear, eye, olfactory epithelium, branchial arches, heart and limb, suggesting possible overlapping functions of NSUN proteins in neural, craniofacial, cardiac, and limb morphogenesis. Furthermore, Nsun2 and Nsun6 enrich in the caudal neural tube and newly formed somites, suggesting possible functions in body axis extension. These results suggest possible overlapping functions of NSUN proteins and RNA methylation in broad aspects of embryonic development.
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Affiliation(s)
- Lijun Chi
- Program in Physiology and Experimental Medicine, The Hospital for Sick Children, Toronto, ON, Canada.
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42
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Sibbritt T, Patel HR, Preiss T. Mapping and significance of the mRNA methylome. WILEY INTERDISCIPLINARY REVIEWS-RNA 2013; 4:397-422. [PMID: 23681756 DOI: 10.1002/wrna.1166] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Revised: 03/20/2013] [Accepted: 03/22/2013] [Indexed: 12/25/2022]
Abstract
Internal methylation of eukaryotic mRNAs in the form of N6-methyladenosine (m(6)A) and 5-methylcytidine (m(5)C) has long been known to exist, but progress in understanding its role was hampered by difficulties in identifying individual sites. This was recently overcome by high-throughput sequencing-based methods that mapped thousands of sites for both modifications throughout mammalian transcriptomes, with most sites found in mRNAs. The topology of m(6)A in mouse and human revealed both conserved and variable sites as well as plasticity in response to extracellular cues. Within mRNAs, m(5)C and m(6)A sites were relatively depleted in coding sequences and enriched in untranslated regions, suggesting functional interactions with post-transcriptional gene control. Finer distribution analyses and preexisting literature point toward roles in the regulation of mRNA splicing, translation, or decay, through an interplay with RNA-binding proteins and microRNAs. The methyltransferase (MTase) METTL3 'writes' m(6)A marks on mRNA, whereas the demethylase FTO can 'erase' them. The RNA:m(5)C MTases NSUN2 and TRDMT1 have roles in tRNA methylation but they also act on mRNA. Proper functioning of these enzymes is important in development and there are clear links to human disease. For instance, a common variant of FTO is a risk allele for obesity carried by 1 billion people worldwide and mutations cause a lethal syndrome with growth retardation and brain deficits. NSUN2 is linked to cancer and stem cell biology and mutations cause intellectual disability. In this review, we summarize the advances, open questions, and intriguing possibilities in this emerging field that might be called RNA modomics or epitranscriptomics.
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Affiliation(s)
- Tennille Sibbritt
- Genome Biology Department, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
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Identification of direct targets and modified bases of RNA cytosine methyltransferases. Nat Biotechnol 2013; 31:458-64. [PMID: 23604283 PMCID: PMC3791587 DOI: 10.1038/nbt.2566] [Citation(s) in RCA: 336] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2013] [Accepted: 04/02/2013] [Indexed: 12/24/2022]
Abstract
The extent and biological impact of RNA cytosine methylation are poorly understood, in part owing to limitations of current techniques for determining the targets of RNA methyltransferases. Here we describe 5-azacytidine-mediated RNA immunoprecipitation (Aza-IP), a mechanism-based technique that exploits the covalent bond formed between an RNA methyltransferase and the cytidine analog 5-azacytidine to recover RNA targets by immunoprecipitation. Targets are subsequently identified by high-throughput sequencing. When applied in a human cell line to the RNA methyltransferases DNMT2 and NSUN2, Aza-IP enabled >200-fold enrichment of tRNAs that are known targets of the enzymes. In addition, it revealed many tRNA and non-coding RNA targets not previously associated with NSUN2. Notably, we observed a high frequency of C>G transversions at the cytosine residues targeted by both enzymes, allowing identification of the specific methylated cytosine(s) in target RNAs. Given the mechanistic similarity of cytosine RNA methyltransferases, Aza-IP may be generally applicable for target identification.
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