1
|
D’Ambrosi S, García-Vílchez R, Kedra D, Vitali P, Macias-Cámara N, Bárcena L, Gonzalez-Lopez M, Aransay AM, Dietmann S, Hurtado A, Blanco S. Global and single-nucleotide resolution detection of 7-methylguanosine in RNA. RNA Biol 2024; 21:1-18. [PMID: 38566310 PMCID: PMC10993922 DOI: 10.1080/15476286.2024.2337493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/27/2024] [Indexed: 04/04/2024] Open
Abstract
RNA modifications, including N-7-methylguanosine (m7G), are pivotal in governing RNA stability and gene expression regulation. The accurate detection of internal m7G modifications is of paramount significance, given recent associations between altered m7G deposition and elevated expression of the methyltransferase METTL1 in various human cancers. The development of robust m7G detection techniques has posed a significant challenge in the field of epitranscriptomics. In this study, we introduce two methodologies for the global and accurate identification of m7G modifications in human RNA. We introduce borohydride reduction sequencing (Bo-Seq), which provides base resolution mapping of m7G modifications. Bo-Seq achieves exceptional performance through the optimization of RNA depurination and scission, involving the strategic use of high concentrations of NaBH4, neutral pH and the addition of 7-methylguanosine monophosphate (m7GMP) during the reducing reaction. Notably, compared to NaBH4-based methods, Bo-Seq enhances the m7G detection performance, and simplifies the detection process, eliminating the necessity for intricate chemical steps and reducing the protocol duration. In addition, we present an antibody-based approach, which enables the assessment of m7G relative levels across RNA molecules and biological samples, however it should be used with caution due to limitations associated with variations in antibody quality between batches. In summary, our novel approaches address the pressing need for reliable and accessible methods to detect RNA m7G methylation in human cells. These advancements hold the potential to catalyse future investigations in the critical field of epitranscriptomics, shedding light on the complex regulatory roles of m7G in gene expression and its implications in cancer biology.
Collapse
Affiliation(s)
- Silvia D’Ambrosi
- Department of Neurosurgery, Cancer Center Amsterdam, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio, Spain
| | - Raquel García-Vílchez
- Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, Salamanca, Spain
| | - Darek Kedra
- Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, Salamanca, Spain
| | - Patrice Vitali
- Molecular, Cellular and Developmental Biology unit (MCD), Centre de Biologie Integrative (CBI), University of Toulouse, UPS, CNRS, Toulouse, France
| | - Nuria Macias-Cámara
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio, Spain
| | - Laura Bárcena
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio, Spain
| | - Monika Gonzalez-Lopez
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio, Spain
| | - Ana M. Aransay
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Madrid, Spain
| | - Sabine Dietmann
- Department of Developmental Biology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Antonio Hurtado
- Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, Salamanca, Spain
| | - Sandra Blanco
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio, Spain
- Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, Salamanca, Spain
| |
Collapse
|
2
|
De Zoysa T, Hauke AC, Iyer NR, Marcus E, Ostrowski SM, Fay JC, Phizicky EM. A connection between the ribosome and two S. pombe tRNA modification mutants subject to rapid tRNA decay. bioRxiv 2023:2023.09.18.558340. [PMID: 37790432 PMCID: PMC10542129 DOI: 10.1101/2023.09.18.558340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
tRNA modifications are crucial in all organisms to ensure tRNA folding and stability, and accurate translation in the ribosome. In both the yeast Saccharomyces cerevisiae and the evolutionarily distant yeast Schizosaccharomyces pombe, mutants lacking certain tRNA body modifications (outside the anticodon loop) are temperature sensitive due to rapid tRNA decay (RTD) of a subset of hypomodified tRNAs. Here we show that for each of two S. pombe mutants subject to RTD, mutations in ribosomal protein genes suppress the temperature sensitivity without altering tRNA levels. Prior work showed that S. pombe trm8Δ mutants, lacking 7-methylguanosine, were temperature sensitive due to RTD and that one class of suppressors had mutations in the general amino acid control (GAAC) pathway, which was activated concomitant with RTD, resulting in further tRNA loss. We now find that another class of S. pombe trm8Δ suppressors have mutations in rpl genes, encoding 60S subunit proteins, and that suppression occurs with minimal restoration of tRNA levels and reduced GAAC activation. Furthermore, trm8Δ suppression extends to other mutations in the large or small ribosomal subunit. We also find that S. pombe tan1Δ mutants, lacking 4-acetylcytidine, are temperature sensitive due to RTD, that one class of suppressors have rpl mutations, associated with minimal restoration of tRNA levels, and that suppression extends to other rpl and rps mutations. However, although S. pombe tan1Δ temperature sensitivity is associated with some GAAC activation, suppression by an rpl mutation does not significantly inhibit GAAC activation. These results suggest that ribosomal protein mutations suppress the temperature sensitivity of S. pombe trm8Δ and tan1Δ mutants due to reduced ribosome concentrations, leading to both a reduced requirement for tRNA, and reduced ribosome collisions and GAAC activation. Results with S. cerevisiae trm8Δ trm4Δ mutants are consistent with this model, and fuel speculation that similar results will apply across eukaryotes.
Collapse
Affiliation(s)
- Thareendra De Zoysa
- Department of Biochemistry and Biophysics, Center for RNA Biology, University of Rochester School of Medicine, Rochester, NY, USA 14642
| | - Alayna C. Hauke
- Department of Biochemistry and Biophysics, Center for RNA Biology, University of Rochester School of Medicine, Rochester, NY, USA 14642
| | - Nivedita R. Iyer
- Department of Biochemistry and Biophysics, Center for RNA Biology, University of Rochester School of Medicine, Rochester, NY, USA 14642
| | - Erin Marcus
- Department of Biochemistry and Biophysics, Center for RNA Biology, University of Rochester School of Medicine, Rochester, NY, USA 14642
| | - Sarah M. Ostrowski
- Department of Biochemistry and Biophysics, Center for RNA Biology, University of Rochester School of Medicine, Rochester, NY, USA 14642
| | - Justin C. Fay
- Department of Biology, University of Rochester, Rochester, NY, USA 14627
| | - Eric M. Phizicky
- Department of Biochemistry and Biophysics, Center for RNA Biology, University of Rochester School of Medicine, Rochester, NY, USA 14642
| |
Collapse
|
3
|
García-Vílchez R, Añazco-Guenkova AM, Dietmann S, López J, Morón-Calvente V, D'Ambrosi S, Nombela P, Zamacola K, Mendizabal I, García-Longarte S, Zabala-Letona A, Astobiza I, Fernández S, Paniagua A, Miguel-López B, Marchand V, Alonso-López D, Merkel A, García-Tuñón I, Ugalde-Olano A, Loizaga-Iriarte A, Lacasa-Viscasillas I, Unda M, Azkargorta M, Elortza F, Bárcena L, Gonzalez-Lopez M, Aransay AM, Di Domenico T, Sánchez-Martín MA, De Las Rivas J, Guil S, Motorin Y, Helm M, Pandolfi PP, Carracedo A, Blanco S. METTL1 promotes tumorigenesis through tRNA-derived fragment biogenesis in prostate cancer. Mol Cancer 2023; 22:119. [PMID: 37516825 PMCID: PMC10386714 DOI: 10.1186/s12943-023-01809-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 06/17/2023] [Indexed: 07/31/2023] Open
Abstract
Newly growing evidence highlights the essential role that epitranscriptomic marks play in the development of many cancers; however, little is known about the role and implications of altered epitranscriptome deposition in prostate cancer. Here, we show that the transfer RNA N7-methylguanosine (m7G) transferase METTL1 is highly expressed in primary and advanced prostate tumours. Mechanistically, we find that METTL1 depletion causes the loss of m7G tRNA methylation and promotes the biogenesis of a novel class of small non-coding RNAs derived from 5'tRNA fragments. 5'tRNA-derived small RNAs steer translation control to favour the synthesis of key regulators of tumour growth suppression, interferon pathway, and immune effectors. Knockdown of Mettl1 in prostate cancer preclinical models increases intratumoural infiltration of pro-inflammatory immune cells and enhances responses to immunotherapy. Collectively, our findings reveal a therapeutically actionable role of METTL1-directed m7G tRNA methylation in cancer cell translation control and tumour biology.
Collapse
Affiliation(s)
- Raquel García-Vílchez
- Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, 37007, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, 37007, Salamanca, Spain
| | - Ana M Añazco-Guenkova
- Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, 37007, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, 37007, Salamanca, Spain
| | - Sabine Dietmann
- Washington University School of Medicine in St. Louis, 660S. Euclid Ave, St. Louis, MO, 63110, USA
| | - Judith López
- Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, 37007, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, 37007, Salamanca, Spain
| | - Virginia Morón-Calvente
- Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, 37007, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, 37007, Salamanca, Spain
| | - Silvia D'Ambrosi
- Present Address: Department of Neurosurgery, Cancer Center Amsterdam, Amsterdam UMC, Vrije Universiteit Amsterdam, 1081 HV, Amsterdam, The Netherlands
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, 801 Bld, 48160, Derio, Bizkaia, Spain
| | - Paz Nombela
- Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, 37007, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, 37007, Salamanca, Spain
| | - Kepa Zamacola
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, 801 Bld, 48160, Derio, Bizkaia, Spain
| | - Isabel Mendizabal
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, 801 Bld, 48160, Derio, Bizkaia, Spain
- Ikerbasque, Basque Foundation for Science, 48011, Bilbao, Spain
| | - Saioa García-Longarte
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, 801 Bld, 48160, Derio, Bizkaia, Spain
| | - Amaia Zabala-Letona
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, 801 Bld, 48160, Derio, Bizkaia, Spain
- Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Madrid, Spain
| | - Ianire Astobiza
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, 801 Bld, 48160, Derio, Bizkaia, Spain
- Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Madrid, Spain
| | - Sonia Fernández
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, 801 Bld, 48160, Derio, Bizkaia, Spain
- Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Madrid, Spain
| | - Alejandro Paniagua
- Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, 37007, Salamanca, Spain
| | - Borja Miguel-López
- Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, 37007, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, 37007, Salamanca, Spain
| | - Virginie Marchand
- Université de Lorraine, UAR2008 IBSLor CNRS-UL-INSERM, Biopôle UL, 9, Avenue de La Forêt de Haye, 54505, Vandoeuvre-Les-Nancy, France
| | - Diego Alonso-López
- Bioinformatics Unit, Cancer Research Center (CIC-IBMCC, CSIC/USAL), Consejo Superior de Investigaciones Científicas (CSIC) and University of Salamanca (USAL), 37007, Salamanca, Spain
| | - Angelika Merkel
- Josep Carreras Leukaemia Research Institute (IJC), Badalona, 08916, Barcelona, Catalonia, Spain
- Germans Trias I Pujol Health Science Research Institute, Badalona, 08916, Barcelona, Catalonia, Spain
| | - Ignacio García-Tuñón
- Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, 37007, Salamanca, Spain
| | | | - Ana Loizaga-Iriarte
- Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Madrid, Spain
- Department of Urology, Basurto University Hospital, 48013, Bilbao, Spain
- Traslational Prostate Cancer Research Lab, CIC bioGUNE-Basurto, Biocruces Bizkaia Health Research Institute, Avenida Montevideo 18, 48013, Bilbao, Spain
| | | | - Miguel Unda
- Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Madrid, Spain
- Department of Urology, Basurto University Hospital, 48013, Bilbao, Spain
- Traslational Prostate Cancer Research Lab, CIC bioGUNE-Basurto, Biocruces Bizkaia Health Research Institute, Avenida Montevideo 18, 48013, Bilbao, Spain
| | - Mikel Azkargorta
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, 801 Bld, 48160, Derio, Bizkaia, Spain
- Carlos III Networked Proteomics Platform (ProteoRed-ISCIII), Madrid, Spain
| | - Félix Elortza
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, 801 Bld, 48160, Derio, Bizkaia, Spain
- Carlos III Networked Proteomics Platform (ProteoRed-ISCIII), Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Madrid, Spain
| | - Laura Bárcena
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, 801 Bld, 48160, Derio, Bizkaia, Spain
| | - Monika Gonzalez-Lopez
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, 801 Bld, 48160, Derio, Bizkaia, Spain
| | - Ana M Aransay
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, 801 Bld, 48160, Derio, Bizkaia, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Madrid, Spain
| | - Tomás Di Domenico
- Bioinformatics Unit, Spanish National Cancer Research Centre (CNIO), 28029, Madrid, Spain
| | - Manuel A Sánchez-Martín
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, 37007, Salamanca, Spain
- Servicio de Transgénesis, Nucleus, Universidad de Salamanca, 37007, Salamanca, Spain
| | - Javier De Las Rivas
- Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, 37007, Salamanca, Spain
| | - Sònia Guil
- Josep Carreras Leukaemia Research Institute (IJC), Badalona, 08916, Barcelona, Catalonia, Spain
- Germans Trias I Pujol Health Science Research Institute, Badalona, 08916, Barcelona, Catalonia, Spain
| | - Yuri Motorin
- Université de Lorraine, UAR2008 IBSLor CNRS-UL-INSERM, Biopôle UL, 9, Avenue de La Forêt de Haye, 54505, Vandoeuvre-Les-Nancy, France
- Université de Lorraine, UMR7365 IMoPA CNRS-UL, Biopôle UL, 9, Avenue de La Forêt de Haye, 54505, Vandoeuvre-Les-Nancy, France
| | - Mark Helm
- Institute of Pharmaceutical and Biomedical Sciences, Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Pier Paolo Pandolfi
- Molecular Biotechnology Center (MBC), Department of Molecular Biotechnology and Health Sciences, University of Turin, 10126, Turin, TO, Italy
- William N. Pennington Cancer Center, Renown Health, Nevada System of Higher Education, Reno, NV, 89502, USA
| | - Arkaitz Carracedo
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, 801 Bld, 48160, Derio, Bizkaia, Spain
- Ikerbasque, Basque Foundation for Science, 48011, Bilbao, Spain
- Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Madrid, Spain
- Department of Pathology, Basurto University Hospital, 48013, Bilbao, Spain
- Biochemistry and Molecular Biology Department, University of the Basque Country (UPV/EHU), P. O. Box 644, 48080, Bilbao, Spain
| | - Sandra Blanco
- Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, 37007, Salamanca, Spain.
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, 37007, Salamanca, Spain.
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, 801 Bld, 48160, Derio, Bizkaia, Spain.
| |
Collapse
|
4
|
Li AY, Xiao HN, Zhao ZY, Xiang C, Chen ZY, Wang PX, Xia Y, Yu B, Li H, Xiao T. Prognostic and immune implications of a novel 7-methylguanosine-related microRNA signature in breast invasive carcinoma: from exploration to validation. J Cancer Res Clin Oncol 2023:10.1007/s00432-023-04849-1. [PMID: 37171615 DOI: 10.1007/s00432-023-04849-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Accepted: 05/08/2023] [Indexed: 05/13/2023]
Abstract
OBJECTIVES This study aims to develop and validate a prognostic signature based on 7-methylguanosine-related (M7G-related) miRNAs for predicting prognosis and immune implications in breast invasive carcinoma (BRCA). MATERIALS AND METHODS M7G-related miRNA data of BRCA were obtained from The Cancer Genome Atlas (TCGA). Least absolute shrinkage and selection operator (LASSO)-penalized, univariate, and multivariate Cox regression analyses were used to construct the prognostic signature. Furthermore, the predictive validity was verified using Kaplan-Meier (KM) survival risk and receiver operating characteristic (ROC) plots. Internal random sampling verification was used to simplify and validate the signature. RT-qPCR was used to quantify the expression level of transcriptional profiles. The independent prognostic role of the risk score was validated using univariate and multivariate regression. Single-sample Gene Set Enrichment Analysis (ssGSEA) was used for functional and immune enrichment analysis. RESULTS A total of 18 M7G-related miRNAs were identified to construct the prognostic signature in BRCA. The low-risk group exhibited significantly higher overall survival than the high-risk group in the KM survival plot (P < 0.001). The area under the curve (AUC) for 1-, 3-, and 5-year survivals in the ROC curve were 0.737, 0.724, and 0.702, respectively. The survival significance in the training and testing cohorts was confirmed by random sampling verification. The most prominent miRNAs in the signature were the miR-7, miR-139, miR-10b, and miR-4728. Furthermore, immune scores for B, mast, and Th1 cells varied between risk groups. Our research demonstrated that CD52 was the most positively correlated gene with immune cells and functions in BRCA. CONCLUSION Our study presents a comprehensive and systematic analysis of M7G-related miRNAs to construct a prognostic signature in BRCA. The signature demonstrated excellent prognostic validity, with the risk score as an independent prognostic factor. These results provide critical evidence for further investigation of M7G miRNAs and offer new insights for BRCA patients in the context of effective immunotherapy.
Collapse
Affiliation(s)
- Ao-Yu Li
- Department of Orthopedics, The Second Xiangya Hospital, Central South University, 139 Renmin Road, Changsha, 410011, Hunan Province, China
- Orthopedic Biomedical Materials Engineering Laboratory of Hunan Province, Changsha, China
| | - Hui-Ni Xiao
- Department of Gastroenterology, The Second Affiliated Hospital, University of South China, Hengyang, 421001, Hunan Province, China
| | - Zi-Yue Zhao
- Department of Orthopedics, The Second Xiangya Hospital, Central South University, 139 Renmin Road, Changsha, 410011, Hunan Province, China
- Orthopedic Biomedical Materials Engineering Laboratory of Hunan Province, Changsha, China
| | - Cheng Xiang
- Department of Orthopedics, The Second Xiangya Hospital, Central South University, 139 Renmin Road, Changsha, 410011, Hunan Province, China
- Orthopedic Biomedical Materials Engineering Laboratory of Hunan Province, Changsha, China
| | - Zhuo-Yuan Chen
- Department of Orthopedics, The Second Xiangya Hospital, Central South University, 139 Renmin Road, Changsha, 410011, Hunan Province, China
- Orthopedic Biomedical Materials Engineering Laboratory of Hunan Province, Changsha, China
| | - Ping-Xiao Wang
- Department of Orthopedics, The Second Xiangya Hospital, Central South University, 139 Renmin Road, Changsha, 410011, Hunan Province, China
- Orthopedic Biomedical Materials Engineering Laboratory of Hunan Province, Changsha, China
| | - Yu Xia
- Department of Orthopedics, The Second Xiangya Hospital, Central South University, 139 Renmin Road, Changsha, 410011, Hunan Province, China
- Orthopedic Biomedical Materials Engineering Laboratory of Hunan Province, Changsha, China
| | - Bin Yu
- Department of Orthopedics, The Second Xiangya Hospital, Central South University, 139 Renmin Road, Changsha, 410011, Hunan Province, China
- Orthopedic Biomedical Materials Engineering Laboratory of Hunan Province, Changsha, China
| | - Hui Li
- Department of Orthopedics, The Second Xiangya Hospital, Central South University, 139 Renmin Road, Changsha, 410011, Hunan Province, China.
- Orthopedic Biomedical Materials Engineering Laboratory of Hunan Province, Changsha, China.
| | - Tao Xiao
- Department of Orthopedics, The Second Xiangya Hospital, Central South University, 139 Renmin Road, Changsha, 410011, Hunan Province, China.
- Orthopedic Biomedical Materials Engineering Laboratory of Hunan Province, Changsha, China.
| |
Collapse
|
5
|
Abstract
Esophageal cancer is one of the major life-threatening diseases in the world. RNA methylation is the most common post-transcriptional modification and a wide-ranging regulatory system controlling gene expression. Numerous studies have revealed that dysregulation of RNA methylation is critical for cancer development and progression. However, the diverse role of RNA methylation and its regulators in esophageal cancer remains to be elucidated and summarized. In this review, we focus on the regulation of major RNA methylation, including m 6A, m 5C, and m 7G, as well as the expression patterns and clinical implications of its regulators in esophageal cancer. We systematically summarize how these RNA modifications affect the "life cycle" of target RNAs, including mRNA, microRNA, long non-coding RNA, and tRNA. The downstream signaling pathways associated with RNA methylation during the development and treatment of esophageal cancer are also discussed in detail. Further studies on how these modifications function together in the microenvironment of esophageal cancer will draw a clearer picture of the clinical application of novel and specific therapeutic strategies.
Collapse
Affiliation(s)
- Wangyang Meng
- Department of Thoracic Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
- Department of Immunology and Microbiology, Shanghai Institute of Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Yichao Han
- Department of Thoracic Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
- Department of Immunology and Microbiology, Shanghai Institute of Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Bin Li
- Department of Immunology and Microbiology, Shanghai Institute of Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Hecheng Li
- Department of Thoracic Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| |
Collapse
|
6
|
Schultz SK, Meadows K, Kothe U. Molecular mechanism of tRNA binding by the Escherichia coli N7 guanosine methyltransferase TrmB. J Biol Chem 2023; 299:104612. [PMID: 36933808 PMCID: PMC10130221 DOI: 10.1016/j.jbc.2023.104612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 03/11/2023] [Accepted: 03/12/2023] [Indexed: 03/18/2023] Open
Abstract
Among the large and diverse collection of tRNA modifications, 7-methylguanosine (m7G) is frequently found in the tRNA variable loop at position 46. This modification is introduced by the TrmB enzyme, which is conserved in bacteria and eukaryotes. However, the molecular determinants and the mechanism for tRNA recognition by TrmB are not well understood. Complementing the report of various phenotypes for different organisms lacking TrmB homologs, we report here hydrogen peroxide sensitivity for the Escherichia coli ΔtrmB knockout strain. To gain insight into the molecular mechanism of tRNA binding by E. coli TrmB in real-time, we developed a new assay based on introducing a 4-thiouridine modification at position 8 of in vitro transcribed tRNAPhe enabling us to fluorescently label this unmodified tRNA. Using rapid kinetic stopped-flow measurements with this fluorescent tRNA, we examined the interaction of wildtype and single substitution variants of TrmB with tRNA. Our results reveal the role of SAM for rapid and stable tRNA binding, the rate-limiting nature of m7G46 catalysis for tRNA release, and the importance of residues R26, T127 and R155 across the entire surface of TrmB for tRNA binding.
Collapse
Affiliation(s)
- Sarah K Schultz
- Alberta RNA Research and Training Institute (ARRTI), Department of Chemistry and Biochemistry, University of Lethbridge, Lethbridge, Alberta, Canada; Department of Chemistry, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Kieran Meadows
- Alberta RNA Research and Training Institute (ARRTI), Department of Chemistry and Biochemistry, University of Lethbridge, Lethbridge, Alberta, Canada
| | - Ute Kothe
- Alberta RNA Research and Training Institute (ARRTI), Department of Chemistry and Biochemistry, University of Lethbridge, Lethbridge, Alberta, Canada; Department of Chemistry, University of Manitoba, Winnipeg, Manitoba, Canada.
| |
Collapse
|
7
|
Lu L, Zheng J, Liu B, Wu H, Huang J, Wu L, Li D. The m7G Modification Level and Immune Infiltration Characteristics in Patients with COVID-19. J Multidiscip Healthc 2022; 15:2461-2472. [PMID: 36320552 PMCID: PMC9618243 DOI: 10.2147/jmdh.s385050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 10/14/2022] [Indexed: 11/10/2022] Open
Abstract
Purpose The 7-methylguanosine (m7G)-related genes were used to identify the clinical severity and prognosis of patients with coronavirus disease 2019 (COVID-19) and to identify possible therapeutic targets. Patients and Methods The GSE157103 dataset provides the transcriptional spectrum and clinical information required to analyze the expression of m7G-related genes and the disease subtypes. R language was applied for immune infiltration analysis, functional enrichment analysis, and nomogram model construction. Results Most m7G-related genes were up-regulated in COVID-19 and were closely related to immune cell infiltration. Disease subtypes were grouped using a clustering algorithm. It was found that the m7G-cluster B was associated with higher immune infiltration, lower mechanical ventilation, lower intensive care unit (ICU) status, higher ventilator-free days, and lower m7G scores. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that differentially expressed genes (DEGs) between m7G-cluster A and B were enriched in viral infection and immune-related aspects, including COVID-19 infection; Th17, Th1, and Th2 cell differentiation, and human T-cell leukemia virus 1 infection. Finally, through machine learning, six disease characteristic genes, NUDT4B, IFIT5, LARP1, EIF4E, LSM1, and NUDT4, were screened and used to develop a nomogram model to estimate disease risk. Conclusion The expression of most m7G genes was higher in COVID-19 patients compared with that in non-COVID-19 patients. The m7G-cluster B showed higher immune infiltration and milder symptoms. The predictive nomogram based on the six m7G genes can be used to accurately assess risk.
Collapse
Affiliation(s)
- Lingling Lu
- Fuzong Clinical Medical College of Fujian Medical University, The 900th Hospital, Fuzhou, People’s Republic of China
| | - Jiaolong Zheng
- Fuzong Clinical Medical College of Fujian Medical University, The 900th Hospital, Fuzhou, People’s Republic of China,Department of Hepatobiliary Disease, The 900th Hospital of Joint Logistics Support Force, Fuzhou, People’s Republic of China
| | - Bang Liu
- Fuzong Clinical Medical College of Fujian Medical University, The 900th Hospital, Fuzhou, People’s Republic of China
| | - Haicong Wu
- Fuzong Clinical Medical College of Fujian Medical University, The 900th Hospital, Fuzhou, People’s Republic of China,Department of Hepatobiliary Disease, The 900th Hospital of Joint Logistics Support Force, Fuzhou, People’s Republic of China
| | - Jiaofeng Huang
- Fuzong Clinical Medical College of Fujian Medical University, The 900th Hospital, Fuzhou, People’s Republic of China
| | - Liqing Wu
- Department of Hepatobiliary Disease, The 900th Hospital of Joint Logistics Support Force, Fuzhou, People’s Republic of China
| | - Dongliang Li
- Fuzong Clinical Medical College of Fujian Medical University, The 900th Hospital, Fuzhou, People’s Republic of China,Department of Hepatobiliary Disease, The 900th Hospital of Joint Logistics Support Force, Fuzhou, People’s Republic of China,Correspondence: Dongliang Li, Fuzong Clinical Medical College of Fujian Medical University, The 900th Hospital of the People’s Liberation Army Joint Logistics Support Force, No. 156 Xierhuan Road, Fuzhou, Fujian, 350025, People’s Republic of China, Tel/Fax +86 591 22859128, Email
| |
Collapse
|
8
|
Wang Z, Zhong Z, Jiang Z, Chen Z, Chen Y, Xu Y. A novel prognostic 7-methylguanosine signature reflects immune microenvironment and alternative splicing in glioma based on multi-omics analysis. Front Cell Dev Biol 2022; 10:902394. [PMID: 36036011 PMCID: PMC9399734 DOI: 10.3389/fcell.2022.902394] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 07/15/2022] [Indexed: 02/05/2023] Open
Abstract
Glioma is the most common type of central nervous system tumor with increasing incidence. 7-methylguanosine (m7G) is one of the diverse RNA modifications that is known to regulate RNA metabolism and its dysregulation was associated with various cancers. However, the expression pattern of m7G regulators and their roles in regulating tumor immune microenvironments (TIMEs) as well as alternative splicing events (ASEs) in glioma has not been reported. In this study, we showed that m7G regulators displayed a close correlation with each other and most of them were differentially expressed between normal and glioma tissues. Two m7G signatures were then constructed to predict the overall survival of both GBM and LGG patients with moderate predictive performance. The risk score calculated from the regression coefficient and expression level of signature genes was proved to be an independent prognostic factor for patients with LGG, thus, a nomogram was established on the risk score and other independent clinical parameters to predict the survival probability of LGG patients. We also investigated the correlation of m7G signatures with TIMEs in terms of immune scores, expression levels of HLA and immune checkpoint genes, immune cell composition, and immune-related functions. While exploring the correlation between signature genes and the ASEs in glioma, we found that EIF4E1B was a key regulator and might play dual roles depending on glioma grade. By incorporating spatial transcriptomic data, we found a cluster of cells featured by high expression of PTN exhibited the highest m7G score and may communicate with adjacent cancer cells via SPP1 and PTN signaling pathways. In conclusion, our work brought novel insights into the roles of m7G modification in TIMEs and ASEs in glioma, suggesting that evaluation of m7G in glioma could predict prognosis. Moreover, our data suggested that blocking SPP1 and PTN pathways might be a strategy for combating glioma.
Collapse
Affiliation(s)
- Zihan Wang
- Department of Neurosurgery, The First Affiliated Hospital of Shantou University Medical College, Shantou, China
- Shantou University Medical College, Shantou, China
| | - Zhiwei Zhong
- Department of Neurosurgery, The First Affiliated Hospital of Shantou University Medical College, Shantou, China
- Shantou University Medical College, Shantou, China
- School of Medical Sciences, Edith Cowan University, Joondalup, WA, Australia
| | - Zehua Jiang
- Shantou University Medical College, Shantou, China
- Joint Shantou International Eye Center, Shantou University and the Chinese University of Hong Kong, Shantou, China
| | - Zepeng Chen
- Department of Neurosurgery, The First Affiliated Hospital of Shantou University Medical College, Shantou, China
- Shantou University Medical College, Shantou, China
| | - Yuequn Chen
- Department of Neurosurgery, The First Affiliated Hospital of Shantou University Medical College, Shantou, China
- Shantou University Medical College, Shantou, China
| | - Yimin Xu
- Department of Neurosurgery, The First Affiliated Hospital of Shantou University Medical College, Shantou, China
| |
Collapse
|
9
|
Xin S, Deng Y, Mao J, Wang T, Liu J, Wang S, Song X, Song W, Liu X. Characterization of 7-Methylguanosine Identified Biochemical Recurrence and Tumor Immune Microenvironment in Prostate Cancer. Front Oncol 2022; 12:900203. [PMID: 35677157 PMCID: PMC9168541 DOI: 10.3389/fonc.2022.900203] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Accepted: 04/19/2022] [Indexed: 12/15/2022] Open
Abstract
Prostate cancer (PCa) has a high incidence rate, mortality rate, and biochemical recurrence (BCR) rate. 7-Methylguanosine (m7G), as one of the RNA modifications, has been considered to be actively involved in cancer-related translation disorders in recent years. Therefore, we first used The Cancer Genome Atlas (TCGA) database to identify prognosis and m7G-related long non-coding RNAs (lncRNAs). Then we randomly divided the samples into the training set and test set and then constructed and verified the m7G lnRNA prognostic model (m7Gscore) by the least absolute shrinkage and selection operator (LASSO) regression analysis. The m7Gscore has been proved to be an independent marker of BCR-free survival in patients with PCa. Furthermore, the m7Gscore was significantly correlated with the tumor immune microenvironment (TIME) and somatic mutation of PCa patients and had the potential to be an indicator for the selection of drug treatment. We also clustered TCGA cohort into three m7G-related patterns (C1, C2, and C3). The Kaplan-Meier survival analysis revealed that C1 had the best BCR-free survival and C3 had the worst. The TIME was also significantly distinct among the three m7G-related patterns. According to the TIME characteristics of the patterns, we defined C1, C2, and C3 as immune-desert phenotype, immune-inflamed phenotype, and immune-excluded phenotype, respectively.
Collapse
Affiliation(s)
- Sheng Xin
- Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China.,Institute of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China
| | - Yuxuan Deng
- Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China.,Institute of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China
| | - Jiaquan Mao
- Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China.,Institute of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China
| | - Tao Wang
- Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China.,Institute of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China
| | - Jihong Liu
- Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China.,Institute of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China
| | - Shaogang Wang
- Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China.,Institute of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China
| | - Xiaodong Song
- Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China.,Institute of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China
| | - Wen Song
- Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China.,Institute of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China
| | - Xiaming Liu
- Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China.,Institute of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China
| |
Collapse
|
10
|
Drenichev MS, Dorinova EO, Varizhuk IV, Oslovsky VE, Varga MA, Esipov RS, Lykoshin DD, Alexeev CS. Synthesis of Fluorine-Containing Analogues of Purine Deoxynucleosides: Optimization of Enzymatic Transglycosylation Conditions. DOKL BIOCHEM BIOPHYS 2022; 503:52-58. [PMID: 35538278 PMCID: PMC9090681 DOI: 10.1134/s1607672922020053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 12/01/2021] [Accepted: 12/01/2021] [Indexed: 11/23/2022]
Abstract
In this work, a comparative analysis of the conditions of transglycosylation reactions catalyzed by E. coli nucleoside phosphorylases was carried out, and the optimal conditions for the formation of various nucleosides were determined. Under the optimized conditions of transglycosylation reaction, fluorine-containing derivatives of N6-benzyl-2'-deoxyadenosine, potential inhibitors of replication of enteroviruses in a cell, were obtained starting from the corresponding ribonucleosides.
Collapse
Affiliation(s)
- M S Drenichev
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | - E O Dorinova
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | - I V Varizhuk
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | - V E Oslovsky
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | - M A Varga
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | - R S Esipov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - D D Lykoshin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - C S Alexeev
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia.
| |
Collapse
|
11
|
Gameiro PA, Encheva V, Dos Santos MS, MacRae JI, Ule J. Metabolic turnover and dynamics of modified ribonucleosides by 13C labeling. J Biol Chem 2021; 297:101294. [PMID: 34634303 PMCID: PMC8567201 DOI: 10.1016/j.jbc.2021.101294] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 09/21/2021] [Accepted: 09/22/2021] [Indexed: 01/27/2023] Open
Abstract
Tandem mass spectrometry (MS/MS) is an accurate tool to assess modified ribonucleosides and their dynamics in mammalian cells. However, MS/MS quantification of lowly abundant modifications in non-ribosomal RNAs is unreliable, and the dynamic features of various modifications are poorly understood. Here, we developed a 13C labeling approach, called 13C-dynamods, to quantify the turnover of base modifications in newly transcribed RNA. This turnover-based approach helped to resolve mRNA from ncRNA modifications in purified RNA or free ribonucleoside samples and showed the distinct kinetics of the N6-methyladenosine (m6A) versus 7-methylguanosine (m7G) modification in polyA+-purified RNA. We uncovered that N6,N6-dimethyladenosine (m62A) exhibits distinct turnover in small RNAs and free ribonucleosides when compared to known m62A-modified large rRNAs. Finally, combined measurements of turnover and abundance of these modifications informed on the transcriptional versus posttranscriptional sensitivity of modified ncRNAs and mRNAs, respectively, to stress conditions. Thus, 13C-dynamods enables studies of the origin of modified RNAs at steady-state and subsequent dynamics under nonstationary conditions. These results open new directions to probe the presence and biological regulation of modifications in particular RNAs.
Collapse
Affiliation(s)
- Paulo A Gameiro
- RNA Networks Laboratory, Francis Crick Institute, London, UK; Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, UK.
| | - Vesela Encheva
- Mass Spectrometry Science Technology Platform, Francis Crick Institute, London, UK
| | | | - James I MacRae
- Mass Spectrometry Science Technology Platform, Francis Crick Institute, London, UK
| | - Jernej Ule
- RNA Networks Laboratory, Francis Crick Institute, London, UK; Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, UK
| |
Collapse
|
12
|
Shanmugasundaram M, Senthilvelan A, Kore AR. Chemical Synthesis of a Locked Nucleic Acid-Substituted Dinucleotide Cap Analog. Curr Protoc 2021; 1:e22. [PMID: 33484497 DOI: 10.1002/cpz1.22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
This article describes a reliable and efficient method for synthesis of the dinucleotide cap analog m7(LNA) G[5']ppp[5']G containing a locked nucleic acid moiety. The required LNA intermediate for the final coupling reaction, m7(LNA) GDP, is prepared in six steps starting from 5'-DMTr-N-DMF LNA guanosine. The overall reaction involves removal of DMTr and DMF groups, 5' monophosphorylation, imidazolide formation, diphosphorylation, and regioselective m7 methylation. The final coupling reaction of m7(LNA) GDP with ImGMP in the presence of zinc chloride as a catalyst affords m7(LNA) G[5']ppp[5']G in 59% yield. © 2021 Wiley Periodicals LLC. Basic Protocol: Synthesis of an LNA-substituted dinucleotide cap analog Support Protocol: Preparation of the tris(tributylammonium) phosphate linker.
Collapse
Affiliation(s)
| | | | - Anilkumar R Kore
- Life Sciences Solutions Group, Thermo Fisher Scientific, Austin, Texas
| |
Collapse
|
13
|
Blersch KF, Burchert JP, August SC, Welp L, Neumann P, Köster S, Urlaub H, Ficner R. Structural model of the M7G46 Methyltransferase TrmB in complex with tRNA. RNA Biol 2021; 18:2466-2479. [PMID: 34006170 DOI: 10.1080/15476286.2021.1925477] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
TrmB belongs to the class I S-adenosylmethionine (SAM)-dependent methyltransferases (MTases) and introduces a methyl group to guanine at position 7 (m7G) in tRNA. In tRNAs m7G is most frequently found at position 46 in the variable loop and forms a tertiary base pair with C13 and U22, introducing a positive charge at G46. The TrmB/Trm8 enzyme family is structurally diverse, as TrmB proteins exist in a monomeric, homodimeric, and heterodimeric form. So far, the exact enzymatic mechanism, as well as the tRNA-TrmB crystal structure is not known. Here we present the first crystal structures of B. subtilis TrmB in complex with SAM and SAH. The crystal structures of TrmB apo and in complex with SAM and SAH have been determined by X-ray crystallography to 1.9 Å (apo), 2.5 Å (SAM), and 3.1 Å (SAH). The obtained crystal structures revealed Tyr193 to be important during SAM binding and MTase activity. Applying fluorescence polarization, the dissociation constant Kd of TrmB and tRNAPhe was determined to be 0.12 µM ± 0.002 µM. Luminescence-based methyltransferase activity assays revealed cooperative effects during TrmB catalysis with half-of-the-site reactivity at physiological SAM concentrations. Structural data retrieved from small-angle x-ray scattering (SAXS), mass-spectrometry of cross-linked complexes, and molecular docking experiments led to the determination of the TrmB-tRNAPhe complex structure.
Collapse
Affiliation(s)
- Katharina F Blersch
- Department of Molecular Structural Biology, Institute of Microbiology and Genetics, GZMB, Georg August University Göttingen, Göttingen, Germany
| | - Jan-Philipp Burchert
- Institute for X-Ray Physics, Georg August University Göttingen, Göttingen, Germany
| | | | - Luisa Welp
- Bioanalytical Mass Spectrometry Research Group, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Piotr Neumann
- Department of Molecular Structural Biology, Institute of Microbiology and Genetics, GZMB, Georg August University Göttingen, Göttingen, Germany
| | - Sarah Köster
- Institute for X-Ray Physics, Georg August University Göttingen, Göttingen, Germany
| | - Henning Urlaub
- Bioanalytical Mass Spectrometry Research Group, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany.,Bioanalytics Group, Institute for Clinical Chemistry, University Medical Center Göttingen, Göttingen, Germany
| | - Ralf Ficner
- Department of Molecular Structural Biology, Institute of Microbiology and Genetics, GZMB, Georg August University Göttingen, Göttingen, Germany
| |
Collapse
|
14
|
Golojuch S, Kopcial M, Strzelecka D, Kasprzyk R, Baran N, Sikorski PJ, Kowalska J, Jemielity J. Exploring tryptamine conjugates as pronucleotides of phosphate-modified 7-methylguanine nucleotides targeting cap-dependent translation. Bioorg Med Chem 2020; 28:115523. [PMID: 32362385 DOI: 10.1016/j.bmc.2020.115523] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 03/23/2020] [Accepted: 04/17/2020] [Indexed: 12/14/2022]
Abstract
Eukaryotic translation initiation factor 4E (eIF4E) is overexpressed in many cancers deregulating translational control of the cell cycle. mRNA 5' cap analogs targeting eIF4E are small molecules with the potential to counteract elevated levels of eIF4E in cancer cells. However, the practical utility of typical cap analogs is limited because of their reduced cell membrane permeability. Transforming the active analogs into their pronucleotide derivatives is a promising approach to overcome this obstacle. 7-Benzylguanosine monophosphate (bn7GMP) is a cap analog that has been successfully transformed into a cell-penetrating pronucleotide by conjugation of the phosphate moiety with tryptamine. In this work, we explored whether a similar strategy is applicable to other cap analogs, particularly phosphate-modified 7-methylguanine nucleotides. We report the synthesis of six new tryptamine conjugates containing N7-methylguanosine mono- and diphosphate and their analogs modified with thiophosphate moiety. These new potential pronucleotides and the expected products of their activation were characterized by biophysical and biochemical methods to determine their affinity towards eIF4E, their ability to inhibit translation in vitro, their susceptibility to enzymatic degradation and their turnover in cell extract. The results suggest that compounds containing the thiophosphate moiety may act as pronucleotides that release low but sustainable concentrations of 7-methylguanosine 5'-phosphorothioate (m7GMPS), which is a translation inhibitor with in vitro potency higher than bn7GMP.
Collapse
Affiliation(s)
- Sebastian Golojuch
- Centre of New Technologies, University of Warsaw, S. Banacha 2c, 02-097 Warsaw, Poland; Faculty of Chemistry, University of Warsaw, L. Pasteura 1, 02-093 Warsaw, Poland
| | - Michal Kopcial
- Centre of New Technologies, University of Warsaw, S. Banacha 2c, 02-097 Warsaw, Poland; Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, L. Pasteura 5, 02-093 Warsaw, Poland; College of Inter-Faculty Individual Studies in Mathematics and Natural Sciences, University of Warsaw, Banacha 2c, 02-097 Warsaw, Poland
| | - Dominika Strzelecka
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, L. Pasteura 5, 02-093 Warsaw, Poland
| | - Renata Kasprzyk
- Centre of New Technologies, University of Warsaw, S. Banacha 2c, 02-097 Warsaw, Poland; Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, L. Pasteura 5, 02-093 Warsaw, Poland; College of Inter-Faculty Individual Studies in Mathematics and Natural Sciences, University of Warsaw, Banacha 2c, 02-097 Warsaw, Poland
| | - Natalia Baran
- Centre of New Technologies, University of Warsaw, S. Banacha 2c, 02-097 Warsaw, Poland; Faculty of Biology, University of Warsaw, I. Miecznikowa 1, 02-096 Warsaw, Poland
| | - Pawel J Sikorski
- Centre of New Technologies, University of Warsaw, S. Banacha 2c, 02-097 Warsaw, Poland
| | - Joanna Kowalska
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, L. Pasteura 5, 02-093 Warsaw, Poland.
| | - Jacek Jemielity
- Centre of New Technologies, University of Warsaw, S. Banacha 2c, 02-097 Warsaw, Poland.
| |
Collapse
|
15
|
Galloway A, Atrih A, Grzela R, Darzynkiewicz E, Ferguson MAJ, Cowling VH. CAP-MAP: cap analysis protocol with minimal analyte processing, a rapid and sensitive approach to analysing mRNA cap structures. Open Biol 2020; 10:190306. [PMID: 32097574 PMCID: PMC7058934 DOI: 10.1098/rsob.190306] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Eukaryotic messenger RNA (mRNA) is modified by the addition of an inverted guanosine cap to the 5' triphosphate. The cap guanosine and initial transcribed nucleotides are further methylated by a series of cap methyltransferases to generate the mature cap structures which protect RNA from degradation and recruit proteins involved in RNA processing and translation. Research demonstrating that the cap methyltransferases are regulated has generated interest in determining the methylation status of the mRNA cap structures present in cells. Here, we present CAP-MAP: cap analysis protocol with minimal analyte processing, a rapid and sensitive method for detecting cap structures present in mRNA isolated from tissues or cultured cells.
Collapse
Affiliation(s)
- Alison Galloway
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Abdelmadjid Atrih
- FingerPrints Proteomics Facility, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Renata Grzela
- Centre of New Technologies, University of Warsaw, 02-097 Warsaw, Poland
| | - Edward Darzynkiewicz
- Centre of New Technologies, University of Warsaw, 02-097 Warsaw, Poland.,Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, 02-097 Warsaw, Poland
| | - Michael A J Ferguson
- Wellcome Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Victoria H Cowling
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| |
Collapse
|
16
|
Senthilvelan A, Shanmugasundaram M, Kore AR. Highly Regioselective Methylation of Guanosine Nucleotides: An Efficient Synthesis of 7-Methylguanosine Nucleotides. ACTA ACUST UNITED AC 2020; 79:e100. [PMID: 31756051 DOI: 10.1002/cpnc.100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This article describes a simple, reliable, efficient, and general method for the synthesis of 7-methylguanosine nucleotides such as 7-methylguanosine 5'-O-monophosphate (m7 GMP), 7-methylguanosine 5'-O-diphosphate (m7 GDP), 7-methyl-2'-deoxyguanosine 5'-O-triphosphate (m7 2'dGTP), and 7-methylguanosine 5'-O-triphosphate (m7 GTP) starting from the corresponding guanosine nucleotide is described. The present protocol involves methylation reaction of guanosine nucleotide using dimethyl sulfate as a methylating agent and water as a solvent at room temperature to provide the corresponding 7-methylguanosine nucleotide in good yields with high purity (>99.5%). It is noteworthy that the present methylation reaction proceeds smoothly under aqueous conditions that is highly regioselective to afford exclusive 7-methylguanosine nucleotide. © 2019 by John Wiley & Sons, Inc. Basic Protocol: Synthesis of 7-methylguanosine nucleotides.
Collapse
Affiliation(s)
| | | | - Anilkumar R Kore
- Life Sciences Solutions Group, Thermo Fisher Scientific, Austin, Texas
| |
Collapse
|
17
|
Pandolfini L, Barbieri I, Bannister AJ, Hendrick A, Andrews B, Webster N, Murat P, Mach P, Brandi R, Robson SC, Migliori V, Alendar A, d'Onofrio M, Balasubramanian S, Kouzarides T. METTL1 Promotes let-7 MicroRNA Processing via m7G Methylation. Mol Cell 2019; 74:1278-1290.e9. [PMID: 31031083 PMCID: PMC6591002 DOI: 10.1016/j.molcel.2019.03.040] [Citation(s) in RCA: 264] [Impact Index Per Article: 52.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 03/06/2019] [Accepted: 03/27/2019] [Indexed: 12/21/2022]
Abstract
7-methylguanosine (m7G) is present at mRNA caps and at defined internal positions within tRNAs and rRNAs. However, its detection within low-abundance mRNAs and microRNAs (miRNAs) has been hampered by a lack of sensitive detection strategies. Here, we adapt a chemical reactivity assay to detect internal m7G in miRNAs. Using this technique (Borohydride Reduction sequencing [BoRed-seq]) alongside RNA immunoprecipitation, we identify m7G within a subset of miRNAs that inhibit cell migration. We show that the METTL1 methyltransferase mediates m7G methylation within miRNAs and that this enzyme regulates cell migration via its catalytic activity. Using refined mass spectrometry methods, we map m7G to a single guanosine within the let-7e-5p miRNA. We show that METTL1-mediated methylation augments let-7 miRNA processing by disrupting an inhibitory secondary structure within the primary miRNA transcript (pri-miRNA). These results identify METTL1-dependent N7-methylation of guanosine as a new RNA modification pathway that regulates miRNA structure, biogenesis, and cell migration.
Collapse
Affiliation(s)
- Luca Pandolfini
- The Gurdon Institute and Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, UK
| | - Isaia Barbieri
- The Gurdon Institute and Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, UK; Division of Cellular and Molecular Pathology, Department of Pathology, University of Cambridge, Addenbroke's Hospital, Cambridge CB2 0QQ, UK
| | - Andrew J Bannister
- The Gurdon Institute and Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, UK
| | - Alan Hendrick
- Storm Therapeutics, Ltd., Moneta Building (B280), Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Byron Andrews
- Storm Therapeutics, Ltd., Moneta Building (B280), Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Natalie Webster
- Storm Therapeutics, Ltd., Moneta Building (B280), Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Pierre Murat
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
| | - Pia Mach
- The Gurdon Institute and Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, UK
| | - Rossella Brandi
- Fondazione EBRI Rita Levi-Montalcini, Genomics Laboratory, Viale Regina Elena 295, 00161 Rome, Italy
| | - Samuel C Robson
- The Gurdon Institute and Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, UK
| | - Valentina Migliori
- The Gurdon Institute and Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, UK
| | - Andrej Alendar
- The Gurdon Institute and Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, UK
| | - Mara d'Onofrio
- Fondazione EBRI Rita Levi-Montalcini, Genomics Laboratory, Viale Regina Elena 295, 00161 Rome, Italy; IFT-CNR, Via del Fosso del Cavaliere 100, 00133 Rome, Italy
| | | | - Tony Kouzarides
- The Gurdon Institute and Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, UK.
| |
Collapse
|
18
|
Kopcial M, Wojtczak BA, Kasprzyk R, Kowalska J, Jemielity J. N1-Propargylguanosine Modified mRNA Cap Analogs: Synthesis, Reactivity, and Applications to the Study of Cap-Binding Proteins. Molecules 2019; 24:molecules24101899. [PMID: 31108861 PMCID: PMC6572376 DOI: 10.3390/molecules24101899] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 05/14/2019] [Accepted: 05/15/2019] [Indexed: 01/07/2023] Open
Abstract
The mRNA 5′ cap consists of N7-methylguanosine bound by a 5′,5′-triphosphate bridge to the first nucleotide of the transcript. The cap interacts with various specific proteins and participates in all key mRNA-related processes, which may be of therapeutic relevance. There is a growing demand for new biophysical and biochemical methods to study cap–protein interactions and identify the factors which inhibit them. The development of such methods can be aided by the use of properly designed fluorescent molecular probes. Herein, we synthesized a new class of m7Gp3G cap derivatives modified with an alkyne handle at the N1-position of guanosine and, using alkyne-azide cycloaddition, we functionalized them with fluorescent tags to obtain potential probes. The cap derivatives and probes were evaluated in the context of two cap-binding proteins, eukaryotic translation initiation factor (eIF4E) and decapping scavenger (DcpS). Biochemical and biophysical studies revealed that N1-propargyl moiety did not significantly disturb cap–protein interaction. The fluorescent properties of the probes turned out to be in line with microscale thermophoresis (MST)-based binding assays.
Collapse
Affiliation(s)
- Michal Kopcial
- College of Inter-Faculty Individual Studies in Mathematics and Natural Sciences, University of Warsaw, S. Banacha 2c, 02-097 Warsaw, Poland.
- Centre of New Technologies, University of Warsaw; S. Banacha 2c, 02-097 Warsaw, Poland.
- Faculty of Physics, University of Warsaw; L. Pasteura 5, 02-093 Warsaw, Poland.
| | - Blazej A Wojtczak
- Centre of New Technologies, University of Warsaw; S. Banacha 2c, 02-097 Warsaw, Poland.
| | - Renata Kasprzyk
- College of Inter-Faculty Individual Studies in Mathematics and Natural Sciences, University of Warsaw, S. Banacha 2c, 02-097 Warsaw, Poland.
- Centre of New Technologies, University of Warsaw; S. Banacha 2c, 02-097 Warsaw, Poland.
- Faculty of Physics, University of Warsaw; L. Pasteura 5, 02-093 Warsaw, Poland.
| | - Joanna Kowalska
- Faculty of Physics, University of Warsaw; L. Pasteura 5, 02-093 Warsaw, Poland.
| | - Jacek Jemielity
- Centre of New Technologies, University of Warsaw; S. Banacha 2c, 02-097 Warsaw, Poland.
| |
Collapse
|
19
|
Devereaux ZJ, Zhu Y, Rodgers MT. Relative glycosidic bond stabilities of naturally occurring methylguanosines: 7-methylation is intrinsically activating. Eur J Mass Spectrom (Chichester) 2019; 25:16-29. [PMID: 30189754 DOI: 10.1177/1469066718798097] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The frequency and diversity of posttranscriptional modifications add an additional layer of chemical complexity beyond canonical nucleic acid sequence. Methylations are particularly frequently occurring and often highly conserved throughout the kingdoms of life. However, the intricate functions of these modified nucleic acid constituents are often not fully understood. Systematic foundational research that reduces systems to their minimum constituents may aid in unraveling the complexities of nucleic acid biochemistry. Here, we examine the relative intrinsic N-glycosidic bond stabilities of guanosine and five naturally occurring methylguanosines (O2'-, 1-, 7-, N2,N2-di-, and N2,N2,O2'-trimethylguanosine) probed by energy-resolved collision-induced dissociation tandem mass spectrometry and complemented with quantum chemical calculations. Apparent glycosidic bond stability is generally found to increase with increasing methyl substitution (canonical < mono- < di- < trimethylated). Many biochemical transformations, including base excision repair mechanisms, involve protonation and/or noncovalent interactions to increase nucleobase leaving-group ability. The protonated gas-phase methylguanosines require less activation energy for glycosidic bond cleavage than their sodium cationized forms. However, methylation at the N7 position intrinsically weakens the glycosidic bond of 7-methylguanosine more significantly than subsequent cationization, and thus 7-methylguanosine is suggested to be under perpetually activated conditions. N7 methylation also alters the nucleoside geometric preferences relative to the other systems, including the nucleobase orientation in the neutral form, sugar puckering in the protonated form, and the preferred protonation and sodium cation binding sites. All of the methylated guanosines examined here are predicted to have proton affinities and gas-phase basicities that exceed that of canonical guanosine. Additionally, the proton affinity and gas-phase basicity trends exhibit a roughly inverse correlation with the apparent glycosidic bond stabilities.
Collapse
Affiliation(s)
| | - Y Zhu
- Department of Chemistry, Wayne State University, Detroit, USA
| | - M T Rodgers
- Department of Chemistry, Wayne State University, Detroit, USA
| |
Collapse
|
20
|
Zhu C, Yan Q, Weng C, Hou X, Mao H, Liu D, Feng X, Guang S. Erroneous ribosomal RNAs promote the generation of antisense ribosomal siRNA. Proc Natl Acad Sci U S A 2018; 115:10082-7. [PMID: 30224484 DOI: 10.1073/pnas.1800974115] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Ribosome biogenesis is a multistep process, during which mistakes can occur at any step of pre-rRNA processing, modification, and ribosome assembly. Misprocessed rRNAs are usually detected and degraded by surveillance machineries. Recently, we identified a class of antisense ribosomal siRNAs (risiRNAs) that down-regulate pre-rRNAs through the nuclear RNAi pathway. To further understand the biological roles of risiRNAs, we conducted both forward and reverse genetic screens to search for more suppressor of siRNA (susi) mutants. We isolated a number of genes that are broadly conserved from yeast to humans and are involved in pre-rRNA modification and processing. Among them, SUSI-2(ceRRP8) is homologous to human RRP8 and engages in m1A methylation of the 26S rRNA. C27F2.4(ceBUD23) is an m7G-methyltransferase of the 18S rRNA. E02H1.1(ceDIMT1L) is a predicted m6(2)Am6(2)A-methyltransferase of the 18S rRNA. Mutation of these genes led to a deficiency in modification of rRNAs and elicited accumulation of risiRNAs, which further triggered the cytoplasmic-to-nuclear and cytoplasmic-to-nucleolar translocations of the Argonaute protein NRDE-3. The rRNA processing deficiency also resulted in accumulation of risiRNAs. We also isolated SUSI-3(RIOK-1), which is similar to human RIOK1, that cleaves the 20S rRNA to 18S. We further utilized RNAi and CRISPR-Cas9 technologies to perform candidate-based reverse genetic screens and identified additional pre-rRNA processing factors that suppressed risiRNA production. Therefore, we concluded that erroneous rRNAs can trigger risiRNA generation and subsequently, turn on the nuclear RNAi-mediated gene silencing pathway to inhibit pre-rRNA expression, which may provide a quality control mechanism to maintain homeostasis of rRNAs.
Collapse
|
21
|
Warminski M, Sikorski PJ, Kowalska J, Jemielity J. Applications of Phosphate Modification and Labeling to Study (m)RNA Caps. Top Curr Chem (Cham) 2017; 375:16. [PMID: 28116583 PMCID: PMC5396385 DOI: 10.1007/s41061-017-0106-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Accepted: 01/10/2017] [Indexed: 02/07/2023]
Abstract
The cap is a natural modification present at the 5' ends of eukaryotic messenger RNA (mRNA), which because of its unique structural features, mediates essential biological functions during the process of gene expression. The core structural feature of the mRNA cap is an N7-methylguanosine moiety linked by a 5'-5' triphosphate chain to the first transcribed nucleotide. Interestingly, other RNA 5' end modifications structurally and functionally resembling the m7G cap have been discovered in different RNA types and in different organisms. All these structures contain the 'inverted' 5'-5' oligophosphate bridge, which is necessary for interaction with specific proteins and also serves as a cleavage site for phosphohydrolases regulating RNA turnover. Therefore, cap analogs containing oligophosphate chain modifications or carrying spectroscopic labels attached to phosphate moieties serve as attractive molecular tools for studies on RNA metabolism and modification of natural RNA properties. Here, we review chemical, enzymatic, and chemoenzymatic approaches that enable preparation of modified cap structures and RNAs carrying such structures, with emphasis on phosphate-modified mRNA cap analogs and their potential applications.
Collapse
Affiliation(s)
- Marcin Warminski
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Zwirki i Wigury 93, 02-089, Warsaw, Poland
| | - Pawel J Sikorski
- Centre of New Technologies, University of Warsaw, Banacha 2c, 02-097, Warsaw, Poland
| | - Joanna Kowalska
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Zwirki i Wigury 93, 02-089, Warsaw, Poland.
| | - Jacek Jemielity
- Centre of New Technologies, University of Warsaw, Banacha 2c, 02-097, Warsaw, Poland.
| |
Collapse
|
22
|
Abstract
Communication between the 5′ and 3′ ends of a eukaryotic messenger RNA (mRNA) or viral genomic RNA is a ubiquitous and important strategy used to regulate gene expression. Although the canonical interaction between initiation factor proteins at the 5′ end of an mRNA and proteins bound to the polyadenylate tail at the 3′ end is well known, in fact there are many other strategies used in diverse ways. These strategies can involve “non-canonical” proteins, RNA structures, and direct RNA-RNA base-pairing between distal elements to achieve 5′-to-3′ communication. Likewise, the communication induced by these interactions influences a variety of processes linked to the use and fate of the RNA that contains them. Recent studies are revealing how dynamic these interactions are, possibly changing in response to cellular conditions or to link various phases of the mRNA’s life, from translation to decay. Thus, 5′-to-3′ communication is about more than just making a closed circle; the RNA elements and associated proteins are key players in controlling gene expression at the post-transcriptional level.
Collapse
Affiliation(s)
- Megan E Filbin
- Department of Chemistry, Metropolitan State University of Denver, Denver, Colorado, 80217, USA
| | - Jeffrey S Kieft
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver School of Medicine, Aurora, Colorado, 80045, USA
| |
Collapse
|
23
|
Abstract
c-Myc is upregulated in response to growth factors and transmits the signal to proliferate by altering the gene expression landscape. When genetic alterations result in growth factor-independent c-Myc expression, it can become an oncogene. The majority of human tumour types exhibit a degree of c-Myc deregulation, resulting in unrestrained cell proliferation. c-Myc binds proximal to the promoter region of genes and recruits co-factors including histone acetyltransferases and RNA pol II kinases, which promote transcription. c-Myc also promotes formation of the cap structure at the 5' end of mRNA. The cap is 7-methylguanosine linked to the first transcribed nucleotide of RNA pol II transcripts via a 5' to 5' triphosphate bridge. The cap is added to the first transcribed nucleotide by the capping enzymes, RNGTT and RNMT-RAM. During the early stages of transcription, the capping enzymes are recruited to RNA pol II phosphorylated on Serine-5 of the C-terminal domain. The mRNA cap protects transcripts from degradation during transcription and recruits factors which promote RNA processing including, splicing, export and translation initiation. The proportion of transcripts with a cap structure is increased by elevating c-Myc expression, resulting in increased rates of translation. c-Myc promotes capping by promoting RNA pol II phosphorylation and by upregulating the enzyme SAHH which neutralises the inhibitory bi-product of methylation reactions, SAH. c-Myc-induced capping is required for c-Myc-dependent gene expression and cell proliferation. Targeting capping may represent a new therapeutic opportunity to inhibit c-Myc function in tumours. This article is part of a Special Issue entitled: Myc proteins in cell biology and pathology.
Collapse
Affiliation(s)
- Sianadh Dunn
- MRC Protein Phosphorylation Unit, College of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| | - Victoria H Cowling
- MRC Protein Phosphorylation Unit, College of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK.
| |
Collapse
|
24
|
Rossi A, Ross EJ, Jack A, Sánchez Alvarado A. Molecular cloning and characterization of SL3: a stem cell-specific SL RNA from the planarian Schmidtea mediterranea. Gene 2013; 533:156-67. [PMID: 24120894 DOI: 10.1016/j.gene.2013.09.101] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Revised: 08/26/2013] [Accepted: 09/26/2013] [Indexed: 01/03/2023]
Abstract
Spliced leader (SL) trans-splicing is a biological phenomenon, common among many metazoan taxa, consisting in the transfer of a short leader sequence from a small SL RNA to the 5' end of a subset of pre-mRNAs. While knowledge of the biochemical mechanisms driving this process has accumulated over the years, the functional consequences of such post-transcriptional event at the organismal level remain unclear. In addition, the fact that functional analyses have been undertaken mainly in trypanosomes and nematodes leaves a somehow fragmented picture of the possible biological significance and evolution of SL trans-splicing in eukaryotes. Here, we analyzed the spatial expression of SL RNAs in the planarian flatworm Schmidtea mediterranea, with the goal of identifying novel developmental paradigms for the study of trans-splicing in metazoans. Besides the previously identified SL1 and SL2, S. mediterranea expresses a third SL RNA described here as SL3. While, SL1 and SL2 are collectively expressed in a broad range of planarian cell types, SL3 is highly enriched in a subset of the planarian stem cells engaged in regenerative responses. Our findings provide new opportunities to study how trans-splicing may regulate the phenotype of a cell.
Collapse
Affiliation(s)
- Alessandro Rossi
- Stowers Institute for Medical Research, 1000 E 50th St., Kansas City, MO 64110, USA.
| | | | | | | |
Collapse
|
25
|
Iio A, Takagi T, Miki K, Naoe T, Nakayama A, Akao Y. DDX6 post-transcriptionally down-regulates miR-143/145 expression through host gene NCR143/145 in cancer cells. Biochim Biophys Acta. 2013;1829:1102-1110. [PMID: 23932921 DOI: 10.1016/j.bbagrm.2013.07.010] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 07/26/2013] [Accepted: 07/31/2013] [Indexed: 12/15/2022]
Abstract
In various human malignancies, widespread dysregulation of microRNA (miRNA) expression is reported to occur and affects various cell growth programs. Recent studies suggest that the expression levels of miRNAs that act as tumor suppressors are frequently reduced in cancers because of chromosome deletions, epigenetical changes, aberrant transcription, and disturbances in miRNA processing. MiR-143 and -145 are well-recognized miRNAs that are highly expressed in several tissues, but down-regulated in most types of cancers. However, the mechanism of this down-regulation has not been investigated in detail. Here, we show that DEAD-box RNA helicase 6, DDX6 (p54/RCK), post-transcriptionally down-regulated miR-143/145 expression by prompting the degradation of its host gene product, NCR143/145 RNA. In human gastric cancer cell line MKN45, DDX6 protein was abundantly expressed and accumulated in processing bodies (P-bodies). DDX6 preferentially increased the instability of non-coding RNA, NCR143/145, which encompasses the miR-143/145 cluster, and down-regulated the expression of mature miR-143/145. In human monocytic cell line THP-1, lipopolysaccharide treatment promoted the assembly of P-bodies and down-regulated the expression of NCR143/145 and its miR-143/145 rapidly. In these cells, cycloheximide treatment led to a loss of P-bodies and to an increase in NCR143/145 RNA stability, thus resulting in up-regulation of miR-143/145 expression. These data demonstrate that DDX6 contributed to the control of NCR143/145 RNA stability in P-bodies and post-transcriptionally regulated miR-143/145 expression in cancer cells.
Collapse
|
26
|
Abstract
The guanine-N7 methyltransferase domain of vaccinia virus mRNA capping enzyme is a heterodimer composed of a catalytic subunit and a stimulatory subunit. Structure-function analysis of the catalytic subunit by alanine scanning and conservative substitutions (49 mutations at 25 amino acids) identified 12 functional groups essential for methyltransferase activity in vivo, most of which were essential for cap methylation in vitro. Defects in cap binding were demonstrated for a subset of lethal mutants that displayed residual activity in vitro. We discuss our findings in light of a model of the Michaelis complex derived from crystal structures of AdoHcy-bound vaccinia cap methyltransferase and GTP-bound cellular cap methyltransferase. The structure-function data yield a coherent picture of the vaccinia cap methyltransferase active site and the determinants of substrate specificity and affinity.
Collapse
Affiliation(s)
- Sushuang Zheng
- Molecular Biology Program, Sloan-Kettering Institute, New York, New York 10065, USA
| | | |
Collapse
|
27
|
Alexandrov A, Grayhack EJ, Phizicky EM. tRNA m7G methyltransferase Trm8p/Trm82p: evidence linking activity to a growth phenotype and implicating Trm82p in maintaining levels of active Trm8p. RNA 2005; 11:821-30. [PMID: 15811913 PMCID: PMC1370766 DOI: 10.1261/rna.2030705] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
We show that Saccharomyces cerevisiae strains lacking Trm8p/Trm82p tRNA m7G methyltransferase are temperature-sensitive in synthetic media containing glycerol. Bacterial TRM8 orthologs complement the growth defect of trm8-Delta, trm82-Delta, and trm8-Delta trm82-Delta double mutants, suggesting that bacteria employ a single subunit for Trm8p/Trm82p function. The growth phenotype of trm8 mutants correlates with lack of tRNA m7G methyltransferase activity in vitro and in vivo, based on analysis of 10 mutant alleles of trm8 and bacterial orthologs, and suggests that m7G modification is the cellular function important for growth. Initial examination of the roles of the yeast subunits shows that Trm8p has most of the functions required to effect m7G modification, and that a major role of Trm82p is to maintain cellular levels of Trm8p. Trm8p efficiently cross-links to pre-tRNAPhe in vitro in the presence or absence of Trm82p, in addition to its known residual tRNA m7G modification activity and its SAM-binding domain. Surprisingly, the levels of Trm8p, but not its mRNA, are severely reduced in a trm82-Delta strain. Although Trm8p can be produced in the absence of Trm82p by deliberate overproduction, the resulting protein is inactive, suggesting that a second role of Trm82p is to stabilize Trm8p in an active conformation.
Collapse
Affiliation(s)
- Andrei Alexandrov
- Department of Biochemistry and Biophysics, University of Rochester School of Medicine, 601 Elmwood Ave., Box 712, Rochester, NY 14642, USA
| | | | | |
Collapse
|