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Hussain A, Wang M, Yu D, Zhang J, Naseer QA, Ullah A, Milon Essola J, Zhang X. Medical and molecular biophysical techniques as substantial tools in the era of mRNA-based vaccine technology. Biomater Sci 2024; 12:4117-4135. [PMID: 39016519 DOI: 10.1039/d4bm00561a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/18/2024]
Abstract
The COVID-19 pandemic prompted the advancement of vaccine technology using mRNA delivery into the host cells. Consequently, mRNA-based vaccines have emerged as a practical approach against SARS-CoV-2 owing to their inherent properties, such as cost-effectiveness, rapid manufacturing, and preservation. These features are vital, especially in resource-constrained regions. Nevertheless, the design of mRNA-based vaccines is intricately intertwined with the refinement of biophysical technologies, thereby establishing their high potential. The preparation of mRNA-based vaccines involves a sequence of phases combining medical and molecular biophysical technologies. Furthermore, their efficiency depends on the capability to optimize their positive attributes, thus paving the way for their subsequent preclinical and clinical evaluations. Using biophysical techniques, the characterization of nucleic acids extends from their initial formulation to their cellular internalization abilities and encapsulation in biomolecule complexes, such as lipid nanoparticles (LNPs), for designing mRNA-based LNPs. Furthermore, nanoparticles are subjected to a series of careful screening steps to assess their physical and chemical characteristics before achieving an optimum formulation suitable for preclinical and clinical studies. This review provides a comprehensive understanding of the fundamental role of biophysical techniques in the complex development of mRNA-based vaccines and their role in the recent success during the COVID-19 pandemic.
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Affiliation(s)
- Abid Hussain
- Jiangsu Key Laboratory of Medical Science and Laboratory Medicine, School of Medicine, Jiangsu University, 301 Xuefu Road, Zhenjiang, 212013, Jiangsu, China.
| | - Maoye Wang
- Jiangsu Key Laboratory of Medical Science and Laboratory Medicine, School of Medicine, Jiangsu University, 301 Xuefu Road, Zhenjiang, 212013, Jiangsu, China.
| | - Dan Yu
- Jiangsu Key Laboratory of Medical Science and Laboratory Medicine, School of Medicine, Jiangsu University, 301 Xuefu Road, Zhenjiang, 212013, Jiangsu, China.
| | - Jiahui Zhang
- Jiangsu Key Laboratory of Medical Science and Laboratory Medicine, School of Medicine, Jiangsu University, 301 Xuefu Road, Zhenjiang, 212013, Jiangsu, China.
| | - Qais Ahmad Naseer
- Department of Laboratory Medicine, School of Medicine, Jiangsu University, Zhenjiang 212013, China
| | - Aftab Ullah
- School of Medicine, Huaqiao University, No. 269 Chenghua North Rd., Quanzhou, Fujian 362021, China.
| | - Julien Milon Essola
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, CAS Center for Excellence in Nanoscience, National Centre for Nanoscience and Technology of China, No. 11, First North Road, Zhongguancun, Beijing, 100190, P.R. China.
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Xu Zhang
- Jiangsu Key Laboratory of Medical Science and Laboratory Medicine, School of Medicine, Jiangsu University, 301 Xuefu Road, Zhenjiang, 212013, Jiangsu, China.
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2
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Zhang X, Ma Y, Yu J, Su R, Wang X. Internal m 6 A and m 7 G RNA modifications in hematopoietic system and acute myeloid leukemia. Chin Med J (Engl) 2024; 137:1033-1043. [PMID: 38545694 PMCID: PMC11062654 DOI: 10.1097/cm9.0000000000003073] [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: 11/12/2023] [Indexed: 05/03/2024] Open
Abstract
ABSTRACT Epitranscriptomics focuses on the RNA-modification-mediated post-transcriptional regulation of gene expression. The past decade has witnessed tremendous progress in our understanding of the landscapes and biological functions of RNA modifications, as prompted by the emergence of potent analytical approaches. The hematopoietic system provides a lifelong supply of blood cells, and gene expression is tightly controlled during the differentiation of hematopoietic stem cells (HSCs). The dysregulation of gene expression during hematopoiesis may lead to severe disorders, including acute myeloid leukemia (AML). Emerging evidence supports the involvement of the mRNA modification system in normal hematopoiesis and AML pathogenesis, which has led to the development of small-molecule inhibitors that target N6-methyladenosine (m 6 A) modification machinery as treatments. Here, we summarize the latest findings and our most up-to-date information on the roles of m 6 A and N7-methylguanine in both physiological and pathological conditions in the hematopoietic system. Furthermore, we will discuss the therapeutic potential and limitations of cancer treatments targeting m 6 A.
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Affiliation(s)
- Xiaoxu Zhang
- State Key Laboratory of Common Mechanism Research for Major Diseases, State Key Laboratory for Complex, Severe, and Rare Diseases, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences / Peking Union Medical College, Beijing 100005, China
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA
| | - Yanni Ma
- State Key Laboratory of Common Mechanism Research for Major Diseases, State Key Laboratory for Complex, Severe, and Rare Diseases, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences / Peking Union Medical College, Beijing 100005, China
- The Institute of Blood Transfusion, Chinese Academy of Medical Sciences / Peking Union Medical College, Chengdu,Sichuan 610052, China
- Key Laboratory of RNA and Hematopoietic Regulation, Chinese Academy of Medical Sciences, Beijing 100005, China
- Department of Biochemistry and Molecular Biology, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing 100005, China
| | - Jia Yu
- State Key Laboratory of Common Mechanism Research for Major Diseases, State Key Laboratory for Complex, Severe, and Rare Diseases, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences / Peking Union Medical College, Beijing 100005, China
- The Institute of Blood Transfusion, Chinese Academy of Medical Sciences / Peking Union Medical College, Chengdu,Sichuan 610052, China
- Key Laboratory of RNA and Hematopoietic Regulation, Chinese Academy of Medical Sciences, Beijing 100005, China
- Department of Biochemistry and Molecular Biology, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing 100005, China
| | - Rui Su
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA
| | - Xiaoshuang Wang
- State Key Laboratory of Common Mechanism Research for Major Diseases, State Key Laboratory for Complex, Severe, and Rare Diseases, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences / Peking Union Medical College, Beijing 100005, China
- The Institute of Blood Transfusion, Chinese Academy of Medical Sciences / Peking Union Medical College, Chengdu,Sichuan 610052, China
- Key Laboratory of RNA and Hematopoietic Regulation, Chinese Academy of Medical Sciences, Beijing 100005, China
- Department of Biochemistry and Molecular Biology, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing 100005, China
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Wang X, Zhang Y, Chen K, Liang Z, Ma J, Xia R, de Magalhães JP, Rigden DJ, Meng J, Song B. m7GHub V2.0: an updated database for decoding the N7-methylguanosine (m7G) epitranscriptome. Nucleic Acids Res 2024; 52:D203-D212. [PMID: 37811871 PMCID: PMC10767970 DOI: 10.1093/nar/gkad789] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 08/18/2023] [Accepted: 09/18/2023] [Indexed: 10/10/2023] Open
Abstract
With recent progress in mapping N7-methylguanosine (m7G) RNA methylation sites, tens of thousands of experimentally validated m7G sites have been discovered in various species, shedding light on the significant role of m7G modification in regulating numerous biological processes including disease pathogenesis. An integrated resource that enables the sharing, annotation and customized analysis of m7G data will greatly facilitate m7G studies under various physiological contexts. We previously developed the m7GHub database to host mRNA m7G sites identified in the human transcriptome. Here, we present m7GHub v.2.0, an updated resource for a comprehensive collection of m7G modifications in various types of RNA across multiple species: an m7GDB database containing 430 898 putative m7G sites identified in 23 species, collected from both widely applied next-generation sequencing (NGS) and the emerging Oxford Nanopore direct RNA sequencing (ONT) techniques; an m7GDiseaseDB hosting 156 206 m7G-associated variants (involving addition or removal of an m7G site), including 3238 disease-relevant m7G-SNPs that may function through epitranscriptome disturbance; and two enhanced analysis modules to perform interactive analyses on the collections of m7G sites (m7GFinder) and functional variants (m7GSNPer). We expect that m7Ghub v.2.0 should serve as a valuable centralized resource for studying m7G modification. It is freely accessible at: www.rnamd.org/m7GHub2.
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Affiliation(s)
- Xuan Wang
- Department of Public Health, School of Medicine & Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China
- Department of Biological Sciences, Xi’an Jiaotong-Liverpool University, Suzhou, 215123, China
| | - Yuxin Zhang
- Department of Biological Sciences, Xi’an Jiaotong-Liverpool University, Suzhou, 215123, China
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, L7 8TX, Liverpool, UK
| | - Kunqi Chen
- Key Laboratory of Ministry of Education for Gastrointestinal Cancer, School of Basic Medical Sciences, Fujian Medical University, Fuzhou 350004, China
| | - Zhanmin Liang
- Department of Biological Sciences, Xi’an Jiaotong-Liverpool University, Suzhou, 215123, China
| | - Jiongming Ma
- Department of Biological Sciences, Xi’an Jiaotong-Liverpool University, Suzhou, 215123, China
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, L7 8TX, Liverpool, UK
| | - Rong Xia
- Department of Financial and Actuarial Mathematics, Xi’an Jiaotong-Liverpool University, Suzhou, 215123, China
| | | | - Daniel J Rigden
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, L7 8TX, Liverpool, UK
| | - Jia Meng
- Department of Biological Sciences, Xi’an Jiaotong-Liverpool University, Suzhou, 215123, China
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, L7 8TX, Liverpool, UK
- AI University Research Centre, Xi’an Jiaotong-Liverpool University, Suzhou 215123, China
| | - Bowen Song
- Department of Public Health, School of Medicine & Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China
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Aranega AE, Franco D. Posttranscriptional Regulation by Proteins and Noncoding RNAs. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 1441:313-339. [PMID: 38884719 DOI: 10.1007/978-3-031-44087-8_17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2024]
Abstract
Posttranscriptional regulation comprises those mechanisms occurring after the initial copy of the DNA sequence is transcribed into an intermediate RNA molecule (i.e., messenger RNA) until such a molecule is used as a template to generate a protein. A subset of these posttranscriptional regulatory mechanisms essentially are destined to process the immature mRNA toward its mature form, conferring the adequate mRNA stability, providing the means for pertinent introns excision, and controlling mRNA turnover rate and quality control check. An additional layer of complexity is added in certain cases, since discrete nucleotide modifications in the mature RNA molecule are added by RNA editing, a process that provides large mature mRNA diversity. Moreover, a number of posttranscriptional regulatory mechanisms occur in a cell- and tissue-specific manner, such as alternative splicing and noncoding RNA-mediated regulation. In this chapter, we will briefly summarize current state-of-the-art knowledge of general posttranscriptional mechanisms, while major emphases will be devoted to those tissue-specific posttranscriptional modifications that impact on cardiac development and congenital heart disease.
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Affiliation(s)
- Amelia E Aranega
- Cardiovascular Research Group, Department of Experimental Biology, University of Jaén, Jaén, Spain
| | - Diego Franco
- Cardiovascular Research Group, Department of Experimental Biology, University of Jaén, Jaén, Spain.
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Ziegenhals T, Frieling R, Wolf P, Göbel K, Koch S, Lohmann M, Baiersdörfer M, Fesser S, Sahin U, Kuhn AN. Formation of dsRNA by-products during in vitro transcription can be reduced by using low steady-state levels of UTP. Front Mol Biosci 2023; 10:1291045. [PMID: 38146535 PMCID: PMC10749352 DOI: 10.3389/fmolb.2023.1291045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Accepted: 11/27/2023] [Indexed: 12/27/2023] Open
Abstract
Introduction: Exogeneous messenger ribonucleic acid (mRNA) can be used as therapeutic and preventive medication. However, during the enzymatic production process, commonly called in vitro transcription, by-products occur which can reduce the therapeutic efficacy of mRNA. One such by-product is double-stranded RNA (dsRNA). We therefore sought to limit the generation of dsRNA by-products during in vitro transcription. Materials and methods: In vitro transcription was performed with a DNA template including a poly(A)-tail-encoding region, dinucleotide or trinucleotide cap analogs for cotranscriptional capping, and relevant nucleoside triphosphates. Concentrations of UTP or modified UTP (m1ΨTP) and GTP were reduced and fed over the course of the reaction. mRNA was analyzed for dsRNA contamination, yield of the reaction, RNA integrity, and capping efficiency before translational activity was assessed. Results: Limiting the steady-state level of UTP or m1ΨTP during the enzymatic reaction reduced dsRNA formation, while not affecting mRNA yield or RNA integrity. Capping efficiency was optimized with the use of a combined GTP and UTP or m1ΨTP feed, while still reducing dsRNA formation. Lower dsRNA levels led to higher protein expression from the corresponding mRNAs. Discussion: Low steady-state concentrations of UTP and GTP, fed in combination over the course of the in vitro transcription reaction, produce mRNA with high capping and low levels of dsRNA formation, resulting in high levels of protein expression. This novel approach may render laborious purification steps to remove dsRNA unnecessary.
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Ma L, Ma Q, Deng Q, Zhou J, Zhou Y, Wei Q, Huang Z, Lao X, Du P. N7-methylguanosine-related miRNAs predict hepatocellular carcinoma prognosis and immune therapy. Aging (Albany NY) 2023; 15:12192-12208. [PMID: 37925170 PMCID: PMC10683595 DOI: 10.18632/aging.205172] [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: 06/30/2023] [Accepted: 10/03/2023] [Indexed: 11/06/2023]
Abstract
N7-methylguanosine (m7G) modification has been notably linked with the development of many tumors. However, no investigations have been conducted on whether m7G-related miRNA (m7G-miRNA) is a prognostic index of hepatocellular carcinoma (HCC). Therefore, this investigation aimed to establish a predictive m7G-miRNA signature for efficient HCC prognosis and elucidate the associated immune cell infiltration (ICI) and functions in the tumor microenvironment. RNA sequencing and clinical data on 375 HCC and 50 healthy tissue samples were acquired from The Cancer Genome Atlas database. The m7G-miRNA regulators methyltransferase-like 1 and WD repeat domain 4 were acquired from the TargetScan database. Univariate Cox regression analysis was conducted on the 63 differentially expressed m7G-miRNAs identified. A prognostic signature that consisted of seven miRNAs was identified. According to their risk scores, individuals with HCC were divided into high-risk (HR) and low-risk (LR) cohorts. A Kaplan-Meier test revealed that survival in the HR HCC patients was poorer than in the LR cohort (p < 0.001). The area under the receiver operating characteristic curves of 1-, 3-, and 5-year overall survival were 0.706, 0.695, and 0.715, respectively. A nomogram of sex, risk score, age, and stage indicated the HCC patients' overall survival. Furthermore, it was indicated that the HR and LR patients had different degrees of ICI and immune function. A pathway enrichment analysis revealed the association of several immunity-linked pathways with the risk model. In conclusion, the signature established has great prognostic value and could be used as a new immunotherapy target for individuals with HCC.
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Affiliation(s)
- Liping Ma
- Department of Clinical Laboratory, Minzu Hospital of Guangxi Zhuang Autonomous Region, Affiliated Minzu Hospital of Guangxi Medical University, Nanning, Guangxi, China
| | - Qingwei Ma
- Department of Clinical Laboratory, Minzu Hospital of Guangxi Zhuang Autonomous Region, Affiliated Minzu Hospital of Guangxi Medical University, Nanning, Guangxi, China
| | - Qiaomei Deng
- Department of Clinical Laboratory, Minzu Hospital of Guangxi Zhuang Autonomous Region, Affiliated Minzu Hospital of Guangxi Medical University, Nanning, Guangxi, China
| | - Jilu Zhou
- Department of Clinical Laboratory, Minzu Hospital of Guangxi Zhuang Autonomous Region, Affiliated Minzu Hospital of Guangxi Medical University, Nanning, Guangxi, China
| | - Yingpei Zhou
- Department of Clinical Laboratory, Minzu Hospital of Guangxi Zhuang Autonomous Region, Affiliated Minzu Hospital of Guangxi Medical University, Nanning, Guangxi, China
| | - Qianqian Wei
- Department of Clinical Laboratory, Minzu Hospital of Guangxi Zhuang Autonomous Region, Affiliated Minzu Hospital of Guangxi Medical University, Nanning, Guangxi, China
| | - Zhihu Huang
- Department of Clinical Laboratory, Minzu Hospital of Guangxi Zhuang Autonomous Region, Affiliated Minzu Hospital of Guangxi Medical University, Nanning, Guangxi, China
| | - Xiaoxia Lao
- Department of Clinical Laboratory, Minzu Hospital of Guangxi Zhuang Autonomous Region, Affiliated Minzu Hospital of Guangxi Medical University, Nanning, Guangxi, China
| | - Ping Du
- Department of Gynecology, Minzu Hospital of Guangxi Zhuang Autonomous Region, Affiliated Minzu Hospital of Guangxi Medical University, Nanning, Guangxi, China
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7
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He F, Jacobson A. Eukaryotic mRNA decapping factors: molecular mechanisms and activity. FEBS J 2023; 290:5057-5085. [PMID: 36098474 PMCID: PMC10008757 DOI: 10.1111/febs.16626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/11/2022] [Accepted: 09/12/2022] [Indexed: 11/30/2022]
Abstract
Decapping is the enzymatic removal of 5' cap structures from mRNAs in eukaryotic cells. Cap structures normally enhance mRNA translation and stability, and their excision commits an mRNA to complete 5'-3' exoribonucleolytic digestion and generally ends the physical and functional cellular presence of the mRNA. Decapping plays a pivotal role in eukaryotic cytoplasmic mRNA turnover and is a critical and highly regulated event in multiple 5'-3' mRNA decay pathways, including general 5'-3' decay, nonsense-mediated mRNA decay (NMD), AU-rich element-mediated mRNA decay, microRNA-mediated gene silencing, and targeted transcript-specific mRNA decay. In the yeast Saccharomyces cerevisiae, mRNA decapping is carried out by a single Dcp1-Dcp2 decapping enzyme in concert with the accessory activities of specific regulators commonly known as decapping activators or enhancers. These regulatory proteins include the general decapping activators Edc1, 2, and 3, Dhh1, Scd6, Pat1, and the Lsm1-7 complex, as well as the NMD-specific factors, Upf1, 2, and 3. Here, we focus on in vivo mRNA decapping regulation in yeast. We summarize recently uncovered molecular mechanisms that control selective targeting of the yeast decapping enzyme and discuss new roles for specific decapping activators in controlling decapping enzyme targeting, assembly of target-specific decapping complexes, and the monitoring of mRNA translation. Further, we discuss the kinetic contribution of mRNA decapping for overall decay of different substrate mRNAs and highlight experimental evidence pointing to the functional coordination and physical coupling between events in mRNA deadenylation, decapping, and 5'-3' exoribonucleolytic decay.
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Affiliation(s)
- Feng He
- Department of Microbiology and Physiological Systems, UMass Chan Medical School, 368 Plantation Street, Worcester, MA 01655
| | - Allan Jacobson
- Department of Microbiology and Physiological Systems, UMass Chan Medical School, 368 Plantation Street, Worcester, MA 01655
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Wang C, Hou X, Guan Q, Zhou H, Zhou L, Liu L, Liu J, Li F, Li W, Liu H. RNA modification in cardiovascular disease: implications for therapeutic interventions. Signal Transduct Target Ther 2023; 8:412. [PMID: 37884527 PMCID: PMC10603151 DOI: 10.1038/s41392-023-01638-7] [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: 11/23/2022] [Revised: 08/15/2023] [Accepted: 09/03/2023] [Indexed: 10/28/2023] Open
Abstract
Cardiovascular disease (CVD) is the leading cause of death in the world, with a high incidence and a youth-oriented tendency. RNA modification is ubiquitous and indispensable in cell, maintaining cell homeostasis and function by dynamically regulating gene expression. Accumulating evidence has revealed the role of aberrant gene expression in CVD caused by dysregulated RNA modification. In this review, we focus on nine common RNA modifications: N6-methyladenosine (m6A), N1-methyladenosine (m1A), 5-methylcytosine (m5C), N7-methylguanosine (m7G), N4-acetylcytosine (ac4C), pseudouridine (Ψ), uridylation, adenosine-to-inosine (A-to-I) RNA editing, and modifications of U34 on tRNA wobble. We summarize the key regulators of RNA modification and their effects on gene expression, such as RNA splicing, maturation, transport, stability, and translation. Then, based on the classification of CVD, the mechanisms by which the disease occurs and progresses through RNA modifications are discussed. Potential therapeutic strategies, such as gene therapy, are reviewed based on these mechanisms. Herein, some of the CVD (such as stroke and peripheral vascular disease) are not included due to the limited availability of literature. Finally, the prospective applications and challenges of RNA modification in CVD are discussed for the purpose of facilitating clinical translation. Moreover, we look forward to more studies exploring the mechanisms and roles of RNA modification in CVD in the future, as there are substantial uncultivated areas to be explored.
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Affiliation(s)
- Cong Wang
- Department of Cardiovascular Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
- Clinical Center for Gene Diagnosis and Therapy, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Xuyang Hou
- Department of Cardiovascular Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
- Clinical Center for Gene Diagnosis and Therapy, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Qing Guan
- Department of Cardiovascular Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
- Clinical Center for Gene Diagnosis and Therapy, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Huiling Zhou
- Department of Cardiovascular Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
- Clinical Center for Gene Diagnosis and Therapy, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Li Zhou
- Department of Pathology, National Clinical Research Center for Geriatric Disorders, The Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Lijun Liu
- Department of Cardiovascular Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
- Clinical Center for Gene Diagnosis and Therapy, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Jijia Liu
- Department of Cardiovascular Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Feng Li
- Department of Cardiovascular Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Wei Li
- Department of Radiology, The Third Xiangya Hospital of Central South University, Changsha, Hunan, China.
| | - Haidan Liu
- Department of Cardiovascular Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China.
- Clinical Center for Gene Diagnosis and Therapy, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China.
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9
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Warminski M, Mamot A, Depaix A, Kowalska J, Jemielity J. Chemical Modifications of mRNA Ends for Therapeutic Applications. Acc Chem Res 2023; 56:2814-2826. [PMID: 37782471 PMCID: PMC10586375 DOI: 10.1021/acs.accounts.3c00442] [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: 07/30/2023] [Indexed: 10/03/2023]
Abstract
Messenger ribonucleic acid (mRNA) is the universal cellular instruction for ribosomes to produce proteins. Proteins are responsible for most of the functions of living organisms, and their abnormal structure or activity is the cause of many diseases. mRNA, which is expressed in the cytoplasm and, unlike DNA, does not need to be delivered into the nucleus, appears to be an ideal vehicle for pursuing the idea of gene therapy in which genetic information about proteins is introduced into an organism to exert a therapeutic effect. mRNA molecules of any sequence can be synthesized using the same set of reagents in a cell-free system via a process called in vitro transcription (IVT), which is very convenient for therapeutic applications. However, this does not mean that the path from the idea to the first mRNA-based therapeutic was short and easy. It took 30 years of trial and error in the search for solutions that eventually led to the first mRNA vaccines created in record time during the SARS-CoV-2 pandemic. One of the fundamental problems in the development of RNA-based therapeutics is the legendary instability of mRNA, due to the transient nature of this macromolecule. From the chemical point of view, mRNA is a linear biopolymer composed of four types of ribonucleic subunits ranging in length from a few hundred to hundreds of thousands of nucleotides, with unique structures at its ends: a 5'-cap at the 5'-end and a poly(A) tail at the 3'-end. Both are extremely important for the regulation of translation and mRNA durability. These elements are also convenient sites for sequence-independent labeling of mRNA to create probes for enzymatic assays and tracking of the fate of mRNA in cells and living organisms. Synthetic 5'-cap analogs have played an important role in the studies of mRNA metabolism, and some of them have also been shown to significantly improve the translational properties of mRNA or affect mRNA stability and reactogenicity. The most effective of these is used in clinical trials of mRNA-based anticancer vaccines. Interestingly, thanks to the knowledge gained from the biophysical studies of cap-related processes, even relatively large modifications such as fluorescent tags can be attached to the cap structure without significant effects on the biological properties of the mRNA, if properly designed cap analogs are used. This has been exploited in the development of molecular tools (fluorescently labeled mRNAs) to track these macromolecules in complex biological systems, including organisms. These tools are extremely valuable for better understanding of the cellular mechanisms involved in mRNA metabolism but also for designing therapeutic mRNAs with superior properties. Much less is known about the usefulness/utility of poly(A) tail modifications in the therapeutic context, but it is clear that chemical modifications of poly(A) can also affect biochemical properties of mRNA. This Account is devoted to chemical modifications of both the 5'- and 3'-ends of mRNA aimed at improving the biological properties of mRNA, without interfering with its translational function, and is based on the authors' more than 20 years of experience in this field.
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Affiliation(s)
- Marcin Warminski
- Division
of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
| | - Adam Mamot
- Centre
of New Technologies, University of Warsaw, Banacha 2c, 02-097 Warsaw, Poland
| | - Anaïs Depaix
- 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, Pasteura 5, 02-093 Warsaw, Poland
| | - Jacek Jemielity
- Centre
of New Technologies, University of Warsaw, Banacha 2c, 02-097 Warsaw, Poland
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10
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Zuberek J, Warzecha M, Dobrowolski M, Modrak-Wojcik A. An intramolecular disulphide bond in human 4E-T affects its binding to eIF4E1a protein. EUROPEAN BIOPHYSICS JOURNAL : EBJ 2023; 52:497-510. [PMID: 37798395 PMCID: PMC10618305 DOI: 10.1007/s00249-023-01684-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 09/14/2023] [Accepted: 09/16/2023] [Indexed: 10/07/2023]
Abstract
The cap at the 5'terminus of mRNA is a key determinant of gene expression in eukaryotic cells, which among others is required for cap dependent translation and protects mRNA from degradation. These properties of cap are mediated by several proteins. One of them is 4E-Transporter (4E-T), which plays an important role in translational repression, mRNA decay and P-bodies formation. 4E-T is also one of several proteins that interact with eukaryotic initiation factor 4E (eIF4E), a cap binding protein which is a key component of the translation initiation machinery. The molecular mechanisms underlying the interactions of these two proteins are crucial for mRNA processing. Studying the interactions between human eIF4E1a and the N-terminal fragment of 4E-T that possesses unstructured 4E-binding motifs under non-reducing conditions, we observed that 4E-T preferentially forms an intramolecular disulphide bond. This "disulphide loop" reduces affinity of 4E-T for eIF4E1a by about 300-fold. Considering that only human 4E-T possesses two cysteines located between the 4E binding motifs, we proposed that the disulphide bond may act as a switch to regulate interactions between the two proteins.
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Affiliation(s)
- Joanna Zuberek
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Warsaw, Poland.
| | - Marek Warzecha
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Warsaw, Poland
| | - Mateusz Dobrowolski
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Warsaw, Poland
| | - Anna Modrak-Wojcik
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Warsaw, Poland
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11
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Li Q, Liu H, Li L, Guo H, Xie Z, Kong X, Xu J, Zhang J, Chen Y, Zhang Z, Liu J, Xuan A. Mettl1-mediated internal m 7G methylation of Sptbn2 mRNA elicits neurogenesis and anti-alzheimer's disease. Cell Biosci 2023; 13:183. [PMID: 37779199 PMCID: PMC10544167 DOI: 10.1186/s13578-023-01131-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 09/11/2023] [Indexed: 10/03/2023] Open
Abstract
BACKGROUND N7-methylguanosine (m7G) is one of the most conserved modifications in nucleosides impacting mRNA export, splicing, and translation. However, the precise function and molecular mechanism of internal mRNA m7G methylation in adult hippocampal neurogenesis and neurogenesis-related Alzheimer's disease (AD) remain unknown. RESULTS We profiled the dynamic Mettl1/Wdr4 expressions and m7G modification during neuronal differentiation of neural stem cells (NSCs) in vitro and in vivo. Adult hippocampal neurogenesis and its molecular mechanisms were examined by morphology, biochemical methods and biological sequencing. The translation efficiency of mRNA was detected by polysome profiling. The stability of Sptbn2 mRNA was constructed by RNA stability assay. APPswe/PS1ΔE9 (APP/PS1) double transgenic mice were used as model of AD. Morris water maze was used to detect the cognitive function. METHODS We found that m7G methyltransferase complex Mettl1/Wdr4 as well as m7G was significantly elevated in neurons. Functionally, silencing Mettl1 in neural stem cells (NSCs) markedly decreased m7G modification, neuronal genesis and proliferation in addition to increasing gliogenesis, while forced expression of Mettl1 facilitated neuronal differentiation and proliferation. Mechanistically, the m7G modification of Sptbn2 mRNA by Mettl1 enhanced its stability and translation, which promoted neurogenesis. Importantly, genetic defciency of Mettl1 reduced hippocampal neurogenesis and spatial memory in the adult mice. Furthermore, Mettl1 overexpression in the hippocampus of APP/PS1 mice rescued neurogenesis and behavioral defects. CONCLUSION Our findings unravel the pivotal role of internal mRNA m7G modification in Sptbn2-mediated neurogenesis, and highlight Mettl3 regulation of neurogenesis as a novel therapeutic target in AD treatment.
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Affiliation(s)
- Qingfeng Li
- The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Qingyuan, 511518, China
| | - Hui Liu
- The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Qingyuan, 511518, China
| | - Lishi Li
- The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Qingyuan, 511518, China
| | - Haomin Guo
- The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Qingyuan, 511518, China
| | - Zhihao Xie
- School of Basic Medical Sciences, First Clinical School, School of Health Management, Guangzhou Medical University, Guangzhou, 511436, China
| | - Xuejian Kong
- The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Qingyuan, 511518, China
| | - Jiamin Xu
- The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Qingyuan, 511518, China
| | - Junlin Zhang
- School of Basic Medical Sciences, First Clinical School, School of Health Management, Guangzhou Medical University, Guangzhou, 511436, China
| | - Yunxia Chen
- School of Basic Medical Sciences, First Clinical School, School of Health Management, Guangzhou Medical University, Guangzhou, 511436, China
| | - Zhongsheng Zhang
- The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Qingyuan, 511518, China.
| | - Jun Liu
- Department of Neurology, Institute of Neuroscience, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, 510260, China.
| | - Aiguo Xuan
- The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Qingyuan, 511518, China.
- Department of Neurology, Institute of Neuroscience, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, 510260, China.
- School of Basic Medical Sciences of Guangzhou Medical University, Guangzhou Municipal and Guangdong Provincial Key Laboratory of Protein Modification and Degradation, Guangzhou, 511436, China.
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12
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Solodushko V, Fouty B. Terminal hairpins improve protein expression in IRES-initiated mRNA in the absence of a cap and polyadenylated tail. Gene Ther 2023; 30:620-627. [PMID: 36828937 PMCID: PMC9951143 DOI: 10.1038/s41434-023-00391-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 01/31/2023] [Accepted: 02/08/2023] [Indexed: 02/26/2023]
Abstract
Synthesizing mRNA in vitro is a standard and simple procedure. Adding the 5' cap and 3' polyadenylated (poly(A)) tail to make this mRNA functional for use as a vaccine or therapy increases the time and cost of production and usually decreases the yield, however. We designed mRNA that lacked a cap and poly(A) tail but included an internal ribosomal entry site (IRES) to initiate protein translation. To protect the 5' and 3' ends of mRNA from exonucleases, we added stable terminal hairpins. When compared against typical mRNA (i.e., mRNA that contained a cap and poly(A) tail but lacked hairpins), expression of the delivered reporter protein in HEK293 cells was similar. Using a triple instead of a single hairpin at each end increased protein expression even more. This method has the potential to simplify the production and reduce the cost of synthesizing exogenous mRNA for use as biologics or vaccines.
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Affiliation(s)
- Victor Solodushko
- Department of Pharmacology, University of South Alabama School of Medicine, Mobile, AL, 36688, USA.
- The Center for Lung Biology, University of South Alabama School of Medicine, Mobile, AL, 36688, USA.
| | - Brian Fouty
- Department of Pharmacology, University of South Alabama School of Medicine, Mobile, AL, 36688, USA.
- The Center for Lung Biology, University of South Alabama School of Medicine, Mobile, AL, 36688, USA.
- Department of Internal Medicine, University of South Alabama School of Medicine, Mobile, AL, 36688, USA.
- The Division of Pulmonary and Critical Care Medicine, University of South Alabama School of Medicine, Mobile, AL, 36688, USA.
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13
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Dohnalkova M, Krasnykov K, Mendel M, Li L, Panasenko O, Fleury-Olela F, Vågbø CB, Homolka D, Pillai RS. Essential roles of RNA cap-proximal ribose methylation in mammalian embryonic development and fertility. Cell Rep 2023; 42:112786. [PMID: 37436893 DOI: 10.1016/j.celrep.2023.112786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 05/11/2023] [Accepted: 06/25/2023] [Indexed: 07/14/2023] Open
Abstract
Eukaryotic RNA pol II transcripts are capped at the 5' end by the methylated guanosine (m7G) moiety. In higher eukaryotes, CMTR1 and CMTR2 catalyze cap-proximal ribose methylations on the first (cap1) and second (cap2) nucleotides, respectively. These modifications mark RNAs as "self," blocking the activation of the innate immune response pathway. Here, we show that loss of mouse Cmtr1 or Cmtr2 leads to embryonic lethality, with non-overlapping sets of transcripts being misregulated, but without activation of the interferon pathway. In contrast, Cmtr1 mutant adult mouse livers exhibit chronic activation of the interferon pathway, with multiple interferon-stimulated genes being expressed. Conditional deletion of Cmtr1 in the germline leads to infertility, while global translation is unaffected in the Cmtr1 mutant mouse liver and human cells. Thus, mammalian cap1 and cap2 modifications have essential roles in gene regulation beyond their role in helping cellular transcripts to evade the innate immune system.
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Affiliation(s)
- Michaela Dohnalkova
- Department of Molecular Biology, Science III, University of Geneva, 30 Quai Ernest-Ansermet, 1211 Geneva 4, Switzerland
| | - Kyrylo Krasnykov
- Department of Molecular Biology, Science III, University of Geneva, 30 Quai Ernest-Ansermet, 1211 Geneva 4, Switzerland
| | - Mateusz Mendel
- Department of Molecular Biology, Science III, University of Geneva, 30 Quai Ernest-Ansermet, 1211 Geneva 4, Switzerland
| | - Lingyun Li
- Department of Molecular Biology, Science III, University of Geneva, 30 Quai Ernest-Ansermet, 1211 Geneva 4, Switzerland
| | - Olesya Panasenko
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, 1 Rue Michel Servet, 1211 Geneva 4, Switzerland
| | - Fabienne Fleury-Olela
- Department of Molecular Biology, Science III, University of Geneva, 30 Quai Ernest-Ansermet, 1211 Geneva 4, Switzerland
| | - Cathrine Broberg Vågbø
- Proteomics and Modomics Experimental Core (PROMEC), Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology (NTNU) and St. Olavs Hospital Central Staff, Trondheim, Norway
| | - David Homolka
- Department of Molecular Biology, Science III, University of Geneva, 30 Quai Ernest-Ansermet, 1211 Geneva 4, Switzerland
| | - Ramesh S Pillai
- Department of Molecular Biology, Science III, University of Geneva, 30 Quai Ernest-Ansermet, 1211 Geneva 4, Switzerland.
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14
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Sun H, Zhang Y, Wang G, Yang W, Xu Y. mRNA-Based Therapeutics in Cancer Treatment. Pharmaceutics 2023; 15:pharmaceutics15020622. [PMID: 36839944 PMCID: PMC9964383 DOI: 10.3390/pharmaceutics15020622] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Revised: 01/28/2023] [Accepted: 01/28/2023] [Indexed: 02/15/2023] Open
Abstract
Over the past two decades, significant technological innovations have led to messenger RNA (mRNA) becoming a promising option for developing prophylactic and therapeutic vaccines, protein replacement therapies, and genome engineering. The success of the two COVID-19 mRNA vaccines has sparked new enthusiasm for other medical applications, particularly in cancer treatment. In vitro-transcribed (IVT) mRNAs are structurally designed to resemble naturally occurring mature mRNA. Delivery of IVT mRNA via delivery platforms such as lipid nanoparticles allows host cells to produce many copies of encoded proteins, which can serve as antigens to stimulate immune responses or as additional beneficial proteins for supplements. mRNA-based cancer therapeutics include mRNA cancer vaccines, mRNA encoding cytokines, chimeric antigen receptors, tumor suppressors, and other combination therapies. To better understand the current development and research status of mRNA therapies for cancer treatment, this review focused on the molecular design, delivery systems, and clinical indications of mRNA therapies in cancer.
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Affiliation(s)
- Han Sun
- Department of Biochemistry and Molecular Cell Biology, Shanghai Key Laboratory for Tumor Microenvironment and Inflammation, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Yu Zhang
- Department of Biochemistry and Molecular Cell Biology, Shanghai Key Laboratory for Tumor Microenvironment and Inflammation, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Ge Wang
- Department of Oral Maxillofacial & Head and Neck Oncology, National Center of Stomatology, National Clinical Research Center for Oral Disease, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China
| | - Wen Yang
- Department of Biochemistry and Molecular Cell Biology, Shanghai Key Laboratory for Tumor Microenvironment and Inflammation, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Yingjie Xu
- Department of Biochemistry and Molecular Cell Biology, Shanghai Key Laboratory for Tumor Microenvironment and Inflammation, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
- Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
- Correspondence:
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15
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Muthmann N, Albers M, Rentmeister A. CAPturAM, a Chemo-Enzymatic Strategy for Selective Enrichment and Detection of Physiological CAPAM-Targets. Angew Chem Int Ed Engl 2023; 62:e202211957. [PMID: 36282111 PMCID: PMC10107118 DOI: 10.1002/anie.202211957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 10/23/2022] [Accepted: 10/25/2022] [Indexed: 11/07/2022]
Abstract
Modified nucleotides impact all aspects of eukaryotic mRNAs and contribute to regulation of gene expression at the transcriptional and translational level. At the 5' cap, adenosine as first transcribed nucleotide is often N6 -methyl-2'-O-methyl adenosine (m6 Am ). This modification is tissue dependent and reversible, pointing to a regulatory function. CAPAM was recently identified as methyltransferase responsible for m6 Am formation, however, the direct assignment of its target transcripts proves difficult. Antibodies do not discriminate between internal N6 -methyl adenosine (m6 A) and m6 Am . Here we present CAPturAM, an antibody-free chemical biology approach for direct enrichment and probing of physiological CAPAM-targets. We harness CAPAM's cosubstrate promiscuity to install propargyl groups on its targets. Subsequent functionalization with an affinity handle allows for their enrichment. Using wildtype and CAPAM-/- cells, we successfully applied CAPturAM to confirm or disprove CAPAM-targets, facilitating the verification and identification of CAPAM targets.
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Affiliation(s)
- Nils Muthmann
- Department of Chemistry, Institute of Biochemistry, University of Münster, Corrensstrasse 36, 48149, Münster, Germany
| | - Marvin Albers
- Department of Chemistry, Institute of Biochemistry, University of Münster, Corrensstrasse 36, 48149, Münster, Germany
| | - Andrea Rentmeister
- Department of Chemistry, Institute of Biochemistry, University of Münster, Corrensstrasse 36, 48149, Münster, Germany
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16
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Xia X, Wang Y, Zheng JC. Internal m7G methylation: A novel epitranscriptomic contributor in brain development and diseases. MOLECULAR THERAPY. NUCLEIC ACIDS 2023; 31:295-308. [PMID: 36726408 PMCID: PMC9883147 DOI: 10.1016/j.omtn.2023.01.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
In recent years, N7-methylguanosine (m7G) methylation, originally considered as messenger RNA (mRNA) 5' caps modifications, has been identified at defined internal positions within multiple types of RNAs, including transfer RNAs, ribosomal RNAs, miRNA, and mRNAs. Scientists have put substantial efforts to discover m7G methyltransferases and methylated sites in RNAs to unveil the essential roles of m7G modifications in the regulation of gene expression and determine the association of m7G dysregulation in various diseases, including neurological disorders. Here, we review recent findings regarding the distribution, abundance, biogenesis, modifiers, and functions of m7G modifications. We also provide an up-to-date summary of m7G detection and profile mapping techniques, databases for validated and predicted m7G RNA sites, and web servers for m7G methylation prediction. Furthermore, we discuss the pathological roles of METTL1/WDR-driven m7G methylation in neurological disorders. Last, we outline a roadmap for future directions and trends of m7G modification research, particularly in the central nervous system.
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Affiliation(s)
- Xiaohuan Xia
- Center for Translational Neurodegeneration and Regenerative Therapy, Tongji Hospital affiliated to Tongji University School of Medicine, Shanghai 200072, China,Shanghai Frontiers Science Center of Nanocatalytic Medicine, Shanghai 200331, China,Corresponding author: Xiaohuan Xia, Center for Translational Neurodegeneration and Regenerative Therapy, Tongji Hospital affiliated to Tongji University School of Medicine, Shanghai 200065, China.
| | - Yi Wang
- Shanghai Frontiers Science Center of Nanocatalytic Medicine, Shanghai 200331, China,Translational Research Center, Shanghai Yangzhi Rehabilitation Hospital affiliated to Tongji University School of Medicine, Shanghai 201613, China
| | - Jialin C. Zheng
- Center for Translational Neurodegeneration and Regenerative Therapy, Tongji Hospital affiliated to Tongji University School of Medicine, Shanghai 200072, China,Shanghai Frontiers Science Center of Nanocatalytic Medicine, Shanghai 200331, China,Corresponding author: Jialin C. Zheng, Center for Translational Neurodegeneration and Regenerative Therapy, Tongji Hospital affiliated to Tongji University School of Medicine, Shanghai 200065, China.
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17
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Fu Y, Wang J, Hu Z, Gou Y, Li Y, Jiang Q. A Novel 7-Methylguanosine (m7G)-Related Gene Signature for Overall Survival Prediction in Patient with Clear Cell Renal Cell Carcinoma. JOURNAL OF ONCOLOGY 2023; 2023:9645038. [PMID: 37089261 PMCID: PMC10118881 DOI: 10.1155/2023/9645038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 07/14/2022] [Indexed: 04/25/2023]
Abstract
Clear cell renal cell carcinoma (ccRCC) is the most common pathology type of renal cancer that has an abysmal prognosis. Although a crucial role for 7-methylguanosine modification in cancer cell development has been reported, its role in ccRCC remains uncertain. This study was conducted to determine the efficacy of predictive biomarkers based on m7G-related genes in ccRCC. Firstly, we extracted clinical data and gene expression profiles of ccRCC patients from publicly accessible databases. It identified that 22 of the m7G-related 34 genes were related to overall survival, and 5 of the 22 genes were significantly expressed differently in tumor tissues. Based on Lasso regression analysis, five optimal genes (CYFIP2, EIF4A1, NUDT1, NUDT10, and NUDT4) were chosen to build a new predictive risk model in the TCGA cohort. Validation was carried out with the E-MTAB-1980 cohort. Then, a prognostic nomogram was erected, including the m7G-related gene risk score, age, histological grade, and stage status. Further studies and analysis showed that immune cell infiltration might be associated with the m7G-related risk genes. In addition, the relationship between gene expression and drug response was evaluated by the Pearson correlation test. Therefore, the risk signature with five selected m7G-related genes may be a promising prognostic biomarker and contribute to standardized prognostic assessment for ccRCC.
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Affiliation(s)
- Yongxin Fu
- Department of Urology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Jiawu Wang
- Department of Urology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Zhiya Hu
- Department of Urology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yang Gou
- Department of Urology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yisen Li
- Department of Urology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Qing Jiang
- Department of Urology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
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18
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Ma J, Zhang L, Li S, Liu H. BRPCA: Bounded Robust Principal Component Analysis to Incorporate Similarity Network for N7-Methylguanosine(m 7G) Site-Disease Association Prediction. IEEE/ACM TRANSACTIONS ON COMPUTATIONAL BIOLOGY AND BIOINFORMATICS 2022; 19:3295-3306. [PMID: 34469307 DOI: 10.1109/tcbb.2021.3109055] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Recent studies have revealed that N7-methylguanosine(m7G) plays a pivotal role in various biological processes and disease pathogenesis. To date, transcriptome-wide m7G modification sites have been identified by high-throughput sequencing approaches, and some related information has been recorded in a few biological databases. However, the mechanism of site action in disease remains uncharted. Wet experiments can help identify true m7G sites with high confidence, but it is time-consuming to find the true ones in such a large number of sites, which will also cost too much. Thus, computational methods are emergently needed to predict the associations between m7G sites and various diseases, thus help to uncover potential active sites for specific diseases. In this article, we proposed a bounded robust principal component analysis (BRPCA) method to predict unknown m7G-disease association based on similarity information. Importantly, BRPCA tolerates the noise and redundancy existing in association and similarity information. Moreover, a suitable bounded constraint is incorporated into BRPCA to ensure that the predicted association scores locate in a meaningful interval. The extensive experiments demonstrate the superiority and robustness of the BRPCA.
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19
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Cao J, Liang Y, Gu JJ, Huang Y, Wang B. Construction of prognostic signature of breast cancer based on N7-Methylguanosine-Related LncRNAs and prediction of immune response. Front Genet 2022; 13:991162. [PMID: 36353118 PMCID: PMC9639662 DOI: 10.3389/fgene.2022.991162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 10/12/2022] [Indexed: 11/17/2022] Open
Abstract
Background: Long non-coding RNA (LncRNA) is a prognostic factor for malignancies, and N7-Methylguanosine (m7G) is crucial in the occurrence and progression of tumors. However, it has not been documented how well m7G-related LncRNAs predict the development of breast cancer (BC). This study aims to develop a predictive signature based on long non-coding RNAs (LncRNAs) associated with m7G to predict the prognosis of breast cancer patients. Methods: The Cancer Genome Atlas (TCGA) database provided us with the RNA-seq data and matching clinical information of individuals with breast cancer. To identify the signature of N7-Methylguanosine-Related LncRNAs and create a prognostic model, we employed co-expression network analysis, least absolute shrinkage selection operator (LASSO) regression analysis, univariate Cox regression analysis, and multivariate Cox regression analysis. The signature was assessed using the Kaplan-Meier analysis and Receiver Operating Characteristic (ROC) curve. A nomogram and principal component analysis (PCA) were employed to confirm the predictive signature’s usefulness. Then, we examined the drug sensitivity between the two risk groups and utilized single-sample gene set enrichment analysis (ssGSEA) to investigate the association between predictive factors and the tumor immune microenvironment in high-risk and low-risk groups. Results: Nine m7G-related LncRNAs (LINC01871, AP003469.4, Z68871.1, AC245297.3, EGOT, TFAP2A-AS1, AL136531.1, SEMA3B-AS1, AL606834.2) that are independently associated with the overall survival time (OS) of BC patients make up the signature we developed. For predicting 1-, 3-, and 5-year survival rates, the areas under the ROC curve (AUC) were 0.715, 0.724, and 0.726, respectively. The Kaplan-Meier analysis revealed that the prognosis of BC patients in the high-risk group was worse than that of those in the low-risk group. When compared to clinicopathological variables, multiple regression analysis demonstrated that risk score was a significant independent predictive factor for BC patients. The results of the ssGSEA study revealed a substantial correlation between the predictive traits and the BC patients’ immunological status, low-risk BC patients had more active immune systems, and they responded better to PD1/L1 immunotherapy. Conclusion: The prognostic signature, which is based on m7G-related LncRNAs, can be utilized to inform patients’ customized treatment plans by independently predicting their prognosis and how well they would respond to immunotherapy.
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Affiliation(s)
- Jin Cao
- Medical College, Yangzhou University, Yangzhou, Jiangsu, China
| | - Yichen Liang
- Institute of Oncology, Northern Jiangsu People’s Hospital, Yangzhou, Jiangsu, China
- Department of Oncology, Northern Jiangsu People’s Hospital, Yangzhou, Jiangsu, China
| | - J. Juan Gu
- Medical College, Yangzhou University, Yangzhou, Jiangsu, China
- Institute of Oncology, Northern Jiangsu People’s Hospital, Yangzhou, Jiangsu, China
- Department of Oncology, Northern Jiangsu People’s Hospital, Yangzhou, Jiangsu, China
| | - Yuxiang Huang
- Institute of Oncology, Northern Jiangsu People’s Hospital, Yangzhou, Jiangsu, China
- Department of Oncology, Northern Jiangsu People’s Hospital, Yangzhou, Jiangsu, China
| | - Buhai Wang
- Medical College, Yangzhou University, Yangzhou, Jiangsu, China
- Institute of Oncology, Northern Jiangsu People’s Hospital, Yangzhou, Jiangsu, China
- Department of Oncology, Northern Jiangsu People’s Hospital, Yangzhou, Jiangsu, China
- *Correspondence: Buhai Wang,
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20
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Shoombuatong W, Basith S, Pitti T, Lee G, Manavalan B. THRONE: a new approach for accurate prediction of human RNA N7-methylguanosine sites. J Mol Biol 2022; 434:167549. [DOI: 10.1016/j.jmb.2022.167549] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 03/08/2022] [Accepted: 03/10/2022] [Indexed: 12/30/2022]
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21
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Abstract
In recent years, it has become clear that RNA molecules are involved in almost all vital cellular processes and pathogenesis of human disorders. The functional diversity of RNA comes from its structural richness. Although composed of only four nucleotides, RNA molecules present a plethora of secondary and tertiary structures critical for intra and intermolecular contacts with other RNAs and ligands (proteins, small metabolites, etc.). In order to fully understand RNA function it is necessary to define its spatial structure. Crystallography, nuclear magnetic resonance and cryogenic electron microscopy have demonstrated considerable success in determining the structures of biologically important RNA molecules. However, these powerful methods require large amounts of sample. Despite their limitations, chemical synthesis and in vitro transcription are usually employed to obtain milligram quantities of RNA for structural studies, delivering simple and effective methods for large-scale production of homogenous samples. The aim of this paper is to provide an overview of methods for large-scale RNA synthesis with emphasis on chemical synthesis and in vitro transcription. We also present our own results of testing the efficiency of these approaches in order to adapt the material acquisition strategy depending on the desired RNA construct.
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22
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Quantification of mRNA cap-modifications by means of LC-QqQ-MS. Methods 2021; 203:196-206. [PMID: 34058305 PMCID: PMC7612805 DOI: 10.1016/j.ymeth.2021.05.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 05/25/2021] [Accepted: 05/26/2021] [Indexed: 12/24/2022] Open
Abstract
Enzymatic modification of the 5'-cap is a versatile approach to modulate the properties of mRNAs. Transfer of methyl groups from S-adenosyl-l-methionine (AdoMet) or functional moieties from non-natural analogs by methyltransferases (MTases) allows for site-specific modifications at the cap. These modifications have been used to tune translation or control it in a temporal manner and even influence immunogenicity of mRNA. For quantification of the MTase-mediated cap modification, liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) provides the required sensitivity and accuracy. Here, we describe the complete workflow starting from in vitro transcription to produce mRNAs, via their enzymatic modification at the cap with natural or non-natural moieties to the quantification of these cap-modifications by LC-QqQ-MS.
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23
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Zhang SY, Zhang SW, Zhang T, Fan XN, Meng J. Recent advances in functional annotation and prediction of the epitranscriptome. Comput Struct Biotechnol J 2021; 19:3015-3026. [PMID: 34136099 PMCID: PMC8175281 DOI: 10.1016/j.csbj.2021.05.030] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 05/16/2021] [Accepted: 05/18/2021] [Indexed: 12/17/2022] Open
Abstract
RNA modifications, in particular N6-methyladenosine (m6A), participate in every stages of RNA metabolism and play diverse roles in essential biological processes and disease pathogenesis. Thanks to the advances in sequencing technology, tens of thousands of RNA modification sites can be identified in a typical high-throughput experiment; however, it remains a major challenge to decipher the functional relevance of these sites, such as, affecting alternative splicing, regulation circuit in essential biological processes or association to diseases. As the focus of RNA epigenetics gradually shifts from site discovery to functional studies, we review here recent progress in functional annotation and prediction of RNA modification sites from a bioinformatics perspective. The review covers naïve annotation with associated biological events, e.g., single nucleotide polymorphism (SNP), RNA binding protein (RBP) and alternative splicing, prediction of key sites and their regulatory functions, inference of disease association, and mining the diagnosis and prognosis value of RNA modification regulators. We further discussed the limitations of existing approaches and some future perspectives.
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Affiliation(s)
- Song-Yao Zhang
- Key Laboratory of Information Fusion Technology of Ministry of Education, School of Automation, Northwestern Polytechnical University, Xi'an 710072, China
| | - Shao-Wu Zhang
- Key Laboratory of Information Fusion Technology of Ministry of Education, School of Automation, Northwestern Polytechnical University, Xi'an 710072, China
| | - Teng Zhang
- Key Laboratory of Information Fusion Technology of Ministry of Education, School of Automation, Northwestern Polytechnical University, Xi'an 710072, China
| | - Xiao-Nan Fan
- Key Laboratory of Information Fusion Technology of Ministry of Education, School of Automation, Northwestern Polytechnical University, Xi'an 710072, China
| | - Jia Meng
- Department of Biological Sciences, Xi'an Jiaotong-Liverpool University, Suzhou, Jiangsu 215123, China
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24
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A first exon termination checkpoint preferentially suppresses extragenic transcription. Nat Struct Mol Biol 2021; 28:337-346. [PMID: 33767452 PMCID: PMC7610630 DOI: 10.1038/s41594-021-00572-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 02/12/2021] [Indexed: 01/31/2023]
Abstract
Interactions between the splicing machinery and RNA polymerase II increase protein-coding gene transcription. Similarly, exons and splicing signals of enhancer-generated long noncoding RNAs (elncRNAs) augment enhancer activity. However, elncRNAs are inefficiently spliced, suggesting that, compared with protein-coding genes, they contain qualitatively different exons with a limited ability to drive splicing. We show here that the inefficiently spliced first exons of elncRNAs as well as promoter-antisense long noncoding RNAs (pa-lncRNAs) in human and mouse cells trigger a transcription termination checkpoint that requires WDR82, an RNA polymerase II-binding protein, and its RNA-binding partner of previously unknown function, ZC3H4. We propose that the first exons of elncRNAs and pa-lncRNAs are an intrinsic component of a regulatory mechanism that, on the one hand, maximizes the activity of these cis-regulatory elements by recruiting the splicing machinery and, on the other, contains elements that suppress pervasive extragenic transcription.
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25
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Ma J, Zhang L, Chen J, Song B, Zang C, Liu H. m 7GDisAI: N7-methylguanosine (m 7G) sites and diseases associations inference based on heterogeneous network. BMC Bioinformatics 2021; 22:152. [PMID: 33761868 PMCID: PMC7992861 DOI: 10.1186/s12859-021-04007-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Accepted: 02/08/2021] [Indexed: 12/11/2022] Open
Abstract
Background Recent studies have confirmed that N7-methylguanosine (m7G) modification plays an important role in regulating various biological processes and has associations with multiple diseases. Wet-lab experiments are cost and time ineffective for the identification of disease-associated m7G sites. To date, tens of thousands of m7G sites have been identified by high-throughput sequencing approaches and the information is publicly available in bioinformatics databases, which can be leveraged to predict potential disease-associated m7G sites using a computational perspective. Thus, computational methods for m7G-disease association prediction are urgently needed, but none are currently available at present. Results To fill this gap, we collected association information between m7G sites and diseases, genomic information of m7G sites, and phenotypic information of diseases from different databases to build an m7G-disease association dataset. To infer potential disease-associated m7G sites, we then proposed a heterogeneous network-based model, m7G Sites and Diseases Associations Inference (m7GDisAI) model. m7GDisAI predicts the potential disease-associated m7G sites by applying a matrix decomposition method on heterogeneous networks which integrate comprehensive similarity information of m7G sites and diseases. To evaluate the prediction performance, 10 runs of tenfold cross validation were first conducted, and m7GDisAI got the highest AUC of 0.740(± 0.0024). Then global and local leave-one-out cross validation (LOOCV) experiments were implemented to evaluate the model’s accuracy in global and local situations respectively. AUC of 0.769 was achieved in global LOOCV, while 0.635 in local LOOCV. A case study was finally conducted to identify the most promising ovarian cancer-related m7G sites for further functional analysis. Gene Ontology (GO) enrichment analysis was performed to explore the complex associations between host gene of m7G sites and GO terms. The results showed that m7GDisAI identified disease-associated m7G sites and their host genes are consistently related to the pathogenesis of ovarian cancer, which may provide some clues for pathogenesis of diseases. Conclusion The m7GDisAI web server can be accessed at http://180.208.58.66/m7GDisAI/, which provides a user-friendly interface to query disease associated m7G. The list of top 20 m7G sites predicted to be associted with 177 diseases can be achieved. Furthermore, detailed information about specific m7G sites and diseases are also shown. Supplementary Information The online version contains supplementary material available at 10.1186/s12859-021-04007-9.
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Affiliation(s)
- Jiani Ma
- Engineering Research Center of Intelligent Control for Underground Space, Ministry of Education, China University of Mining and Technology, Xuzhou, 221116, China.,School of Information and Control Engineering, China University of Mining and Technology, Xuzhou, 221116, China
| | - Lin Zhang
- Engineering Research Center of Intelligent Control for Underground Space, Ministry of Education, China University of Mining and Technology, Xuzhou, 221116, China. .,School of Information and Control Engineering, China University of Mining and Technology, Xuzhou, 221116, China.
| | - Jin Chen
- Engineering Research Center of Intelligent Control for Underground Space, Ministry of Education, China University of Mining and Technology, Xuzhou, 221116, China.,School of Information and Control Engineering, China University of Mining and Technology, Xuzhou, 221116, China
| | - Bowen Song
- Department of Biological Sciences, AI University Research Center, Xi'an Jiaotong-Liverpool University, Suzhou, 215123, China
| | - Chenxuan Zang
- Department of Biological Sciences, AI University Research Center, Xi'an Jiaotong-Liverpool University, Suzhou, 215123, China
| | - Hui Liu
- Engineering Research Center of Intelligent Control for Underground Space, Ministry of Education, China University of Mining and Technology, Xuzhou, 221116, China.,School of Information and Control Engineering, China University of Mining and Technology, Xuzhou, 221116, China
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26
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Emery A, Swanstrom R. HIV-1: To Splice or Not to Splice, That Is the Question. Viruses 2021; 13:181. [PMID: 33530363 PMCID: PMC7912102 DOI: 10.3390/v13020181] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 01/21/2021] [Accepted: 01/22/2021] [Indexed: 02/05/2023] Open
Abstract
The transcription of the HIV-1 provirus results in only one type of transcript-full length genomic RNA. To make the mRNA transcripts for the accessory proteins Tat and Rev, the genomic RNA must completely splice. The mRNA transcripts for Vif, Vpr, and Env must undergo splicing but not completely. Genomic RNA (which also functions as mRNA for the Gag and Gag/Pro/Pol precursor polyproteins) must not splice at all. HIV-1 can tolerate a surprising range in the relative abundance of individual transcript types, and a surprising amount of aberrant and even odd splicing; however, it must not over-splice, which results in the loss of full-length genomic RNA and has a dramatic fitness cost. Cells typically do not tolerate unspliced/incompletely spliced transcripts, so HIV-1 must circumvent this cell policing mechanism to allow some splicing while suppressing most. Splicing is controlled by RNA secondary structure, cis-acting regulatory sequences which bind splicing factors, and the viral protein Rev. There is still much work to be done to clarify the combinatorial effects of these splicing regulators. These control mechanisms represent attractive targets to induce over-splicing as an antiviral strategy. Finally, splicing has been implicated in latency, but to date there is little supporting evidence for such a mechanism. In this review we apply what is known of cellular splicing to understand splicing in HIV-1, and present data from our newer and more sensitive deep sequencing assays quantifying the different HIV-1 transcript types.
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MESH Headings
- Alternative Splicing
- Exons
- Gene Expression Regulation, Viral
- HIV-1/genetics
- Nucleic Acid Conformation
- RNA Splicing
- RNA, Messenger/chemistry
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Viral/chemistry
- RNA, Viral/genetics
- RNA, Viral/metabolism
- Regulatory Sequences, Nucleic Acid
- Virus Latency/genetics
- rev Gene Products, Human Immunodeficiency Virus/genetics
- rev Gene Products, Human Immunodeficiency Virus/metabolism
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Affiliation(s)
- Ann Emery
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, USA;
| | - Ronald Swanstrom
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, USA;
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599, USA
- Center for AIDS Research, University of North Carolina, Chapel Hill, NC 27599, USA
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27
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Pelletier J, Schmeing TM, Sonenberg N. The multifaceted eukaryotic cap structure. WILEY INTERDISCIPLINARY REVIEWS-RNA 2020; 12:e1636. [PMID: 33300197 DOI: 10.1002/wrna.1636] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 10/16/2020] [Accepted: 11/03/2020] [Indexed: 12/13/2022]
Abstract
The 5' cap structure is added onto RNA polymerase II transcripts soon after initiation of transcription and modulates several post-transcriptional regulatory events involved in RNA maturation. It is also required for stimulating translation initiation of many cytoplasmic mRNAs and serves to protect mRNAs from degradation. These functional properties of the cap are mediated by several cap binding proteins (CBPs) involved in nuclear and cytoplasmic gene expression steps. The role that CBPs play in gene regulation, as well as the biophysical nature by which they recognize the cap, is quite intricate. Differences in mechanisms of capping as well as nuances in cap recognition speak to the potential of targeting these processes for drug development. In this review, we focus on recent findings concerning the cap epitranscriptome, our understanding of cap binding by different CBPs, and explore therapeutic targeting of CBP-cap interaction. This article is categorized under: RNA Interactions with Proteins and Other Molecules > Protein-RNA Recognition RNA Processing > Capping and 5' End Modifications Translation > Translation Mechanisms.
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Affiliation(s)
- Jerry Pelletier
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada.,Department of Oncology, McGill University, Montreal, Quebec, Canada.,Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, Quebec, Canada.,Centre de Recherche en Biologie Structurale, McGill University, Montreal, Quebec, Canada
| | - T Martin Schmeing
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada.,Centre de Recherche en Biologie Structurale, McGill University, Montreal, Quebec, Canada
| | - Nahum Sonenberg
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada.,Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, Quebec, Canada
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28
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Tellier M, Maudlin I, Murphy S. Transcription and splicing: A two-way street. WILEY INTERDISCIPLINARY REVIEWS. RNA 2020; 11:e1593. [PMID: 32128990 DOI: 10.1002/wrna.1593] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 12/18/2019] [Accepted: 02/12/2020] [Indexed: 12/11/2022]
Abstract
RNA synthesis by RNA polymerase II and RNA processing are closely coupled during the transcription cycle of protein-coding genes. This coupling affords opportunities for quality control and regulation of gene expression and the effects can go in both directions. For example, polymerase speed can affect splice site selection and splicing can increase transcription and affect the chromatin landscape. Here we review the many ways that transcription and splicing influence one another, including how splicing "talks back" to transcription. We will also place the connections between transcription and splicing in the context of other RNA processing events that define the exons that will make up the final mRNA. This article is categorized under: RNA Processing > Splicing Mechanisms RNA Processing > Splicing Regulation/Alternative Splicing.
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Affiliation(s)
- Michael Tellier
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Isabella Maudlin
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Shona Murphy
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
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29
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Song B, Tang Y, Chen K, Wei Z, Rong R, Lu Z, Su J, de Magalhães JP, Rigden DJ, Meng J. m7GHub: deciphering the location, regulation and pathogenesis of internal mRNA N7-methylguanosine (m7G) sites in human. Bioinformatics 2020; 36:3528-3536. [DOI: 10.1093/bioinformatics/btaa178] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Revised: 02/07/2010] [Accepted: 03/09/2020] [Indexed: 12/31/2022] Open
Abstract
Abstract
Motivation
Recent progress in N7-methylguanosine (m7G) RNA methylation studies has focused on its internal (rather than capped) presence within mRNAs. Tens of thousands of internal mRNA m7G sites have been identified within mammalian transcriptomes, and a single resource to best share, annotate and analyze the massive m7G data generated recently are sorely needed.
Results
We report here m7GHub, a comprehensive online platform for deciphering the location, regulation and pathogenesis of internal mRNA m7G. The m7GHub consists of four main components, including: the first internal mRNA m7G database containing 44 058 experimentally validated internal mRNA m7G sites, a sequence-based high-accuracy predictor, the first web server for assessing the impact of mutations on m7G status, and the first database recording 1218 disease-associated genetic mutations that may function through regulation of m7G methylation. Together, m7GHub will serve as a useful resource for research on internal mRNA m7G modification.
Availability and implementation
m7GHub is freely accessible online at www.xjtlu.edu.cn/biologicalsciences/m7ghub.
Contact
kunqi.chen@liverpool.ac.uk
Supplementary information
Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Bowen Song
- Department of Biological Sciences, Xi’an Jiaotong-Liverpool University, Suzhou, Jiangsu 215123, China
| | - Yujiao Tang
- Department of Biological Sciences, Xi’an Jiaotong-Liverpool University, Suzhou, Jiangsu 215123, China
- Institute of Integrative Biology, University of Liverpool, Liverpool L7 8TX, UK
| | - Kunqi Chen
- Department of Biological Sciences, Xi’an Jiaotong-Liverpool University, Suzhou, Jiangsu 215123, China
- Institute of Ageing & Chronic Disease, University of Liverpool, Liverpool L7 8TX, UK
| | - Zhen Wei
- Department of Biological Sciences, Xi’an Jiaotong-Liverpool University, Suzhou, Jiangsu 215123, China
- Institute of Ageing & Chronic Disease, University of Liverpool, Liverpool L7 8TX, UK
| | - Rong Rong
- Department of Biological Sciences, Xi’an Jiaotong-Liverpool University, Suzhou, Jiangsu 215123, China
- Institute of Ageing & Chronic Disease, University of Liverpool, Liverpool L7 8TX, UK
| | - Zhiliang Lu
- Department of Biological Sciences, Xi’an Jiaotong-Liverpool University, Suzhou, Jiangsu 215123, China
- Institute of Ageing & Chronic Disease, University of Liverpool, Liverpool L7 8TX, UK
| | | | | | - Daniel J Rigden
- Institute of Integrative Biology, University of Liverpool, Liverpool L7 8TX, UK
| | - Jia Meng
- Department of Biological Sciences, Xi’an Jiaotong-Liverpool University, Suzhou, Jiangsu 215123, China
- Institute of Ageing & Chronic Disease, University of Liverpool, Liverpool L7 8TX, UK
- AI University Research Centre (AI-URC), Xi’an Jiaotong-Liverpool University, Suzhou, Jiangsu 215123, China
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30
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Abstract
Virtually all in vitro transcription of DNA into RNA is performed with bacteriophage-encoded DNA-dependent RNA polymerases. These enzymes and their characteristics are introduced here.
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31
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RNA-based therapy for osteogenesis. Int J Pharm 2019; 569:118594. [DOI: 10.1016/j.ijpharm.2019.118594] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 08/02/2019] [Accepted: 08/03/2019] [Indexed: 02/06/2023]
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32
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Paquette DR, Tibble RW, Daifuku TS, Gross JD. Control of mRNA decapping by autoinhibition. Nucleic Acids Res 2019; 46:6318-6329. [PMID: 29618050 PMCID: PMC6158755 DOI: 10.1093/nar/gky233] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 03/19/2018] [Indexed: 12/11/2022] Open
Abstract
5′ mediated cytoplasmic RNA decay is a conserved cellular process in eukaryotes. While the functions of the structured core domains in this pathway are well-studied, the role of abundant intrinsically disordered regions (IDRs) is lacking. Here we reconstitute the Dcp1:Dcp2 complex containing a portion of the disordered C-terminus and show its activity is autoinhibited by linear interaction motifs. Enhancers of decapping (Edc) 1 and 3 cooperate to activate decapping by different mechanisms: Edc3 alleviates autoinhibition by binding IDRs and destabilizing an inactive form of the enzyme, whereas Edc1 stabilizes the transition state for catalysis. Both activators are required to fully stimulate an autoinhibited Dcp1:Dcp2 as Edc1 alone cannot overcome the decrease in activity attributed to the C-terminal extension. Our data provide a mechanistic framework for combinatorial control of decapping by protein cofactors, a principle that is likely conserved in multiple 5′ mRNA decay pathways.
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Affiliation(s)
- David R Paquette
- Integrative Program in Quantitative Biology, Graduate Group in Biophysics, University of California, San Francisco, CA 94158, USA.,Department of Pharmaceutical Chemistry, University of California, San Francisco, CA 94158, USA
| | - Ryan W Tibble
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA 94158, USA.,Program in Chemistry and Chemical Biology, University of California, San Francisco, CA 94158, USA
| | - Tristan S Daifuku
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA 94158, USA
| | - John D Gross
- Integrative Program in Quantitative Biology, Graduate Group in Biophysics, University of California, San Francisco, CA 94158, USA.,Department of Pharmaceutical Chemistry, University of California, San Francisco, CA 94158, USA.,Program in Chemistry and Chemical Biology, University of California, San Francisco, CA 94158, USA
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33
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Muthmann N, Guez T, Vasseur JJ, Jaffrey SR, Debart F, Rentmeister A. Combining Chemical Synthesis and Enzymatic Methylation to Access Short RNAs with Various 5' Caps. Chembiochem 2019; 20:1693-1700. [PMID: 30768827 PMCID: PMC6755138 DOI: 10.1002/cbic.201900037] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Indexed: 12/31/2022]
Abstract
Eukaryotic RNAs are heavily processed, including co- and post-transcriptional formation of various 5' caps. In small nuclear RNAs (snRNAs) or small nucleolar RNAs (snoRNAs), the canonical 7m G cap is hypermethylated at the N2 -position, whereas in higher eukaryotes and viruses 2'-O-methylation of the first transcribed nucleotide yields the cap1 structure. The function and potential dynamics of several RNA cap modifications have not been fully elucidated, which necessitates preparative access to these caps. However, the introduction of these modifications during chemical solid-phase synthesis is challenging and enzymatic production of defined short and uniform RNAs also faces difficulties. In this work, the chemical synthesis of RNA is combined with site-specific enzymatic methylation by using the methyltransferases human trimethylguanosine synthase 1 (hTgs1), trimethylguanosine synthase from Giardia lamblia (GlaTgs2), and cap methyltransferase 1 (CMTR1). It is shown that RNAs with di-and trimethylated caps, as well as RNAs with caps methylated at the 2'-O-position of the first transcribed nucleotide, can be conveniently prepared. These highly modified RNAs, with a defined and uniform sequence, are hard to access by in vitro transcription or chemical synthesis alone.
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Affiliation(s)
- Nils Muthmann
- Department of Chemistry and Pharmacy, Institute for Biochemistry, University of Münster, Wilhelm-Klemm-Strasse 2, 48149, Münster, Germany
| | - Théo Guez
- Institut des Biomolécules Max Mousseron (IBMM), Université de Montpellier, CNRS, ENSCM, Campus Triolet UM, Place Eugène Bataillon, 34095, Montpellier, France
| | - Jean-Jacques Vasseur
- Institut des Biomolécules Max Mousseron (IBMM), Université de Montpellier, CNRS, ENSCM, Campus Triolet UM, Place Eugène Bataillon, 34095, Montpellier, France
| | - Samie R Jaffrey
- Department of Pharmacology, Weill Cornell Medicine, Cornell University, 1300 York Avenue, Box 70, New York, NY, 10065, USA
| | - Françoise Debart
- Institut des Biomolécules Max Mousseron (IBMM), Université de Montpellier, CNRS, ENSCM, Campus Triolet UM, Place Eugène Bataillon, 34095, Montpellier, France
| | - Andrea Rentmeister
- Department of Chemistry and Pharmacy, Institute for Biochemistry, University of Münster, Wilhelm-Klemm-Strasse 2, 48149, Münster, Germany
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34
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Ptok J, Müller L, Theiss S, Schaal H. Context matters: Regulation of splice donor usage. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2019; 1862:194391. [PMID: 31202784 DOI: 10.1016/j.bbagrm.2019.06.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 06/07/2019] [Accepted: 06/09/2019] [Indexed: 11/16/2022]
Abstract
Elaborate research on splicing, starting in the late seventies, evolved from the discovery that 5' splice sites are recognized by their complementarity to U1 snRNA towards the realization that RNA duplex formation cannot be the sole basis for 5'ss selection. Rather, their recognition is highly influenced by a number of context factors including transcript architecture as well as splicing regulatory elements (SREs) in the splice site neighborhood. In particular, proximal binding of splicing regulatory proteins highly influences splicing outcome. The importance of SRE integrity especially becomes evident in the light of human pathogenic mutations where single nucleotide changes in SREs can severely affect the resulting transcripts. Bioinformatics tools nowadays greatly assist in the computational evaluation of 5'ss, their neighborhood and the impact of pathogenic mutations. Although predictions are already quite robust, computational evaluation of the splicing regulatory landscape still faces challenges to increase future reliability. This article is part of a Special Issue entitled: RNA structure and splicing regulation edited by Francisco Baralle, Ravindra Singh and Stefan Stamm.
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Affiliation(s)
- Johannes Ptok
- Institute of Virology, Medical Faculty, Heinrich Heine University Düsseldorf, D-40225 Düsseldorf, Germany
| | - Lisa Müller
- Institute of Virology, Medical Faculty, Heinrich Heine University Düsseldorf, D-40225 Düsseldorf, Germany
| | - Stephan Theiss
- Institute of Clinical Neuroscience and Medical Psychology, Medical Faculty, Heinrich Heine University Düsseldorf, D-40225 Düsseldorf, Germany
| | - Heiner Schaal
- Institute of Virology, Medical Faculty, Heinrich Heine University Düsseldorf, D-40225 Düsseldorf, Germany.
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35
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Lu BS, Yin YW, Zhang YP, Guo PY, Li W, Liu KL. Upregulation of NPL4 promotes bladder cancer cell proliferation by inhibiting DXO destabilization of cyclin D1 mRNA. Cancer Cell Int 2019; 19:149. [PMID: 31164795 PMCID: PMC6543671 DOI: 10.1186/s12935-019-0874-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Accepted: 05/27/2019] [Indexed: 12/11/2022] Open
Abstract
Background NPL4 is an important cofactor of the valosin-containing protein (VCP)–NPL4–UFD1 complex. The VCP–NPL4–UFD1 has been considered as a ubiquitin proteasome system (UPS) regulator and response to protein degradation. While NPL4 plays important roles in various diseases, little is known about its functions in bladder cancer (BC). Methods MTT assays and colony forming test were performed to evaluate cell proliferation ability and Western blotting was used to detect protein expression. Cyclin D1 mRNA expression was detected using qRT-PCR, and coimmunoprecipitation (CoIP) was used to detect protein–protein interactions. Results NPL4 was upregulated in BC tissue and correlated with poor prognosis. Upregulation of NPL4 promoted cell proliferation while suppression of NPL4 reduced BC cell proliferation. Upregulation of NPL4 led to overexpression of cyclin D1 by enhancing its mRNA stability. Moreover, NPL4 was found to bind directly to DXO and induce its degradation. DXO was downregulated in BC tissue and regulated BC cell proliferation by destabilizing cyclin D1 mRNA. DXO-mediated NPL4 regulated BC cell proliferation by stabilizing cyclin D1 expression. Conclusions The NPL4/DXO/cyclin D1 axis exert crucial role in BC cell growth and is associated with prognosis and may represent a potential therapeutic target for BC.
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Affiliation(s)
- Bao-Sai Lu
- Department of Urology, The Second Hospital of Hebei Medical University, No. 215, Heping West Road, Shijiazhuang, 050000 Hebei People's Republic of China
| | - Yue-Wei Yin
- Department of Urology, The Second Hospital of Hebei Medical University, No. 215, Heping West Road, Shijiazhuang, 050000 Hebei People's Republic of China
| | - Yan-Ping Zhang
- Department of Urology, The Second Hospital of Hebei Medical University, No. 215, Heping West Road, Shijiazhuang, 050000 Hebei People's Republic of China
| | - Ping-Ying Guo
- Department of Urology, The Second Hospital of Hebei Medical University, No. 215, Heping West Road, Shijiazhuang, 050000 Hebei People's Republic of China
| | - Wei Li
- Department of Urology, The Second Hospital of Hebei Medical University, No. 215, Heping West Road, Shijiazhuang, 050000 Hebei People's Republic of China
| | - Kai-Long Liu
- Department of Urology, The Second Hospital of Hebei Medical University, No. 215, Heping West Road, Shijiazhuang, 050000 Hebei People's Republic of China
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36
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Zhang LS, Liu C, Ma H, Dai Q, Sun HL, Luo G, Zhang Z, Zhang L, Hu L, Dong X, He C. Transcriptome-wide Mapping of Internal N 7-Methylguanosine Methylome in Mammalian mRNA. Mol Cell 2019; 74:1304-1316.e8. [PMID: 31031084 DOI: 10.1016/j.molcel.2019.03.036] [Citation(s) in RCA: 266] [Impact Index Per Article: 53.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2018] [Revised: 02/26/2019] [Accepted: 03/27/2019] [Indexed: 01/05/2023]
Abstract
N7-methylguanosine (m7G) is a positively charged, essential modification at the 5' cap of eukaryotic mRNA, regulating mRNA export, translation, and splicing. m7G also occurs internally within tRNA and rRNA, but its existence and distribution within eukaryotic mRNA remain to be investigated. Here, we show the presence of internal m7G sites within mammalian mRNA. We then performed transcriptome-wide profiling of internal m7G methylome using m7G-MeRIP sequencing (MeRIP-seq). To map this modification at base resolution, we developed a chemical-assisted sequencing approach that selectively converts internal m7G sites into abasic sites, inducing misincorporation at these sites during reverse transcription. This base-resolution m7G-seq enabled transcriptome-wide mapping of m7G in human tRNA and mRNA, revealing distribution features of the internal m7G methylome in human cells. We also identified METTL1 as a methyltransferase that installs a subset of m7G within mRNA and showed that internal m7G methylation could affect mRNA translation.
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Affiliation(s)
- Li-Sheng Zhang
- Department of Chemistry, Department of Biochemistry and Molecular Biology, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, IL 60637, USA; Howard Hughes Medical Institute, The University of Chicago, Chicago, IL 60637, USA
| | - Chang Liu
- Department of Chemistry, Department of Biochemistry and Molecular Biology, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, IL 60637, USA; Howard Hughes Medical Institute, The University of Chicago, Chicago, IL 60637, USA
| | - Honghui Ma
- Liver Cancer Institute, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Institute of Biomedical Sciences, Fudan University, Shanghai 200032, China
| | - Qing Dai
- Department of Chemistry, Department of Biochemistry and Molecular Biology, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, IL 60637, USA; Howard Hughes Medical Institute, The University of Chicago, Chicago, IL 60637, USA
| | - Hui-Lung Sun
- Department of Chemistry, Department of Biochemistry and Molecular Biology, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, IL 60637, USA; Howard Hughes Medical Institute, The University of Chicago, Chicago, IL 60637, USA
| | - Guanzheng Luo
- The State Key Laboratory of Biocontrol, MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou 510060, China
| | - Zijie Zhang
- Department of Chemistry, Department of Biochemistry and Molecular Biology, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, IL 60637, USA; Howard Hughes Medical Institute, The University of Chicago, Chicago, IL 60637, USA
| | - Linda Zhang
- Department of Chemistry, Department of Biochemistry and Molecular Biology, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, IL 60637, USA; Howard Hughes Medical Institute, The University of Chicago, Chicago, IL 60637, USA
| | - Lulu Hu
- Department of Chemistry, Department of Biochemistry and Molecular Biology, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, IL 60637, USA; Howard Hughes Medical Institute, The University of Chicago, Chicago, IL 60637, USA
| | - Xueyang Dong
- College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Chuan He
- Department of Chemistry, Department of Biochemistry and Molecular Biology, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, IL 60637, USA; Howard Hughes Medical Institute, The University of Chicago, Chicago, IL 60637, USA.
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37
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Kramer S, McLennan AG. The complex enzymology of mRNA decapping: Enzymes of four classes cleave pyrophosphate bonds. WILEY INTERDISCIPLINARY REVIEWS. RNA 2019; 10:e1511. [PMID: 30345629 DOI: 10.1002/wrna.1511] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 09/26/2018] [Accepted: 09/27/2018] [Indexed: 12/16/2022]
Abstract
The 5' ends of most RNAs are chemically modified to enable protection from nucleases. In bacteria, this is often achieved by keeping the triphosphate terminus originating from transcriptional initiation, while most eukaryotic mRNAs and small nuclear RNAs have a 5'→5' linked N7 -methyl guanosine (m7 G) cap added. Several other chemical modifications have been described at RNA 5' ends. Common to all modifications is the presence of at least one pyrophosphate bond. To enable RNA turnover, these chemical modifications at the RNA 5' end need to be reversible. Dependent on the direction of the RNA decay pathway (5'→3' or 3'→5'), some enzymes cleave the 5'→5' cap linkage of intact RNAs to initiate decay, while others act as scavengers and hydrolyse the cap element of the remnants of the 3'→5' decay pathway. In eukaryotes, there is also a cap quality control pathway. Most enzymes involved in the cleavage of the RNA 5' ends are pyrophosphohydrolases, with only a few having (additional) 5' triphosphonucleotide hydrolase activities. Despite the identity of their enzyme activities, the enzymes belong to four different enzyme classes. Nudix hydrolases decap intact RNAs as part of the 5'→3' decay pathway, DXO family members mainly degrade faulty RNAs, members of the histidine triad (HIT) family are scavenger proteins, while an ApaH-like phosphatase is the major mRNA decay enzyme of trypanosomes, whose RNAs have a unique cap structure. Many novel cap structures and decapping enzymes have only recently been discovered, indicating that we are only beginning to understand the mechanisms of RNA decapping. This article is categorized under: RNA Turnover and Surveillance > Turnover/Surveillance Mechanisms RNA Turnover and Surveillance > Regulation of RNA Stability RNA Processing > Capping and 5' End Modifications.
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Affiliation(s)
- Susanne Kramer
- Cell and Developmental Biology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Alexander G McLennan
- Department of Biochemistry, Institute of Integrative Biology, University of Liverpool, Liverpool, UK
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38
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Muthmann N, Muttach F, Rentmeister A. Enzymatic Transfer of Photo-Cross-Linkers for RNA-Protein Photo-Cross-Linking at the mRNA 5'-Cap. Methods Mol Biol 2019; 2008:131-146. [PMID: 31124094 DOI: 10.1007/978-1-4939-9537-0_11] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Photo-cross-linking moieties have proven invaluable for elucidating interactions of biomolecules. While methods for site-specific incorporation of those moieties into proteins have been developed, comparable methods for nucleic acids are lacking. Utilizing the inherent specificity of enzymes, methyltransferases (MTase) exhibiting relaxed cosubstrate specificity in combination with synthetic analogs of S-adenosyl-L-methionine (AdoMet) allow for the precise installation of reporter molecules or affinity tags in various biomolecules. In this chapter, we describe AdoMet analogs with photo-cross-linking moieties that-in combination with an MTase-are ideal for site-specific installation. The workflow for chemo-enzymatic installation of photo-cross-linking moieties at the mRNA cap based on AdoMet analogs is given in detail.
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Affiliation(s)
- Nils Muthmann
- Westfälische Wilhelms-Universität Münster, Institute of Biochemistry, Münster, Germany
| | - Fabian Muttach
- Westfälische Wilhelms-Universität Münster, Institute of Biochemistry, Münster, Germany
| | - Andrea Rentmeister
- Westfälische Wilhelms-Universität Münster, Institute of Biochemistry, Münster, Germany. .,Cells-in-Motion Cluster of Excellence (EXC 1003-CiM), University of Muenster, Münster, Germany.
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39
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Grudzien-Nogalska E, Bird JG, Nickels BE, Kiledjian M. "NAD-capQ" detection and quantitation of NAD caps. RNA (NEW YORK, N.Y.) 2018; 24:1418-1425. [PMID: 30045887 PMCID: PMC6140466 DOI: 10.1261/rna.067686.118] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Accepted: 07/16/2018] [Indexed: 05/20/2023]
Abstract
RNA 5' cap structures comprising the metabolic effector nicotinamide adenine dinucleotide (NAD) have been identified in diverse organisms. Here we report a simple, two-step procedure to detect and quantitate NAD-capped RNA, termed "NAD-capQ." By use of NAD-capQ we quantitate NAD-capped RNA levels in Escherichia coli, Saccharomyces cerevisiae, and human cells, and we measure increases in NAD-capped RNA levels in cells from all three organisms harboring disruptions in their respective "deNADding" enzymes. We further show that NAD-capped RNA levels in human cells respond to changes in cellular NAD concentrations, indicating that NAD capping provides a mechanism for human cells to directly sense and respond to alterations in NAD metabolism. Our findings establish NAD-capQ as a versatile, rapid, and accessible methodology to detect and quantitate 5'-NAD caps on endogenous RNA in any organism.
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Affiliation(s)
- Ewa Grudzien-Nogalska
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Jeremy G Bird
- Department of Genetics and Waksman Institute, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Bryce E Nickels
- Department of Genetics and Waksman Institute, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Megerditch Kiledjian
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, New Jersey 08854, USA
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40
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Abstract
Ribonucleic acid (RNA) homeostasis is dynamically modulated in response to changing physiological conditions. Tight regulation of RNA abundance through both transcription and degradation determines the amount, timing, and location of protein translation. This balance is of particular importance in neurons, which are among the most metabolically active and morphologically complex cells in the body. As a result, any disruptions in RNA degradation can have dramatic consequences for neuronal health. In this chapter, we will first discuss mechanisms of RNA stabilization and decay. We will then explore how the disruption of these pathways can lead to neurodegenerative disease.
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41
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Muttach F, Muthmann N, Rentmeister A. Synthetic mRNA capping. Beilstein J Org Chem 2017; 13:2819-2832. [PMID: 30018667 PMCID: PMC5753152 DOI: 10.3762/bjoc.13.274] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 12/04/2017] [Indexed: 12/25/2022] Open
Abstract
Eukaryotic mRNA with its 5'-cap is of central importance for the cell. Many studies involving mRNA require reliable preparation and modification of 5'-capped RNAs. Depending on the length of the desired capped RNA, chemical or enzymatic preparation - or a combination of both - can be advantageous. We review state-of-the art methods and give directions for choosing the appropriate approach. We also discuss the preparation and properties of mRNAs with non-natural caps providing novel features such as improved stability or enhanced translational efficiency.
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Affiliation(s)
- Fabian Muttach
- University of Münster, Department of Chemistry, Institute of Biochemistry, Wilhelm-Klemm-Str. 2, 48149 Münster, Germany
| | - Nils Muthmann
- University of Münster, Department of Chemistry, Institute of Biochemistry, Wilhelm-Klemm-Str. 2, 48149 Münster, Germany
| | - Andrea Rentmeister
- University of Münster, Department of Chemistry, Institute of Biochemistry, Wilhelm-Klemm-Str. 2, 48149 Münster, Germany
- Cells-in-Motion Cluster of Excellence (EXC1003-CiM), University of Münster, Germany
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42
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Kwon H, Kim M, Seo Y, Moon YS, Lee HJ, Lee K, Lee H. Emergence of synthetic mRNA: In vitro synthesis of mRNA and its applications in regenerative medicine. Biomaterials 2017; 156:172-193. [PMID: 29197748 DOI: 10.1016/j.biomaterials.2017.11.034] [Citation(s) in RCA: 104] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 10/25/2017] [Accepted: 11/21/2017] [Indexed: 12/15/2022]
Abstract
The field of gene therapy has evolved over the past two decades after the first introduction of nucleic acid drugs, such as plasmid DNA (pDNA). With the development of in vitro transcription (IVT) methods, synthetic mRNA has become an emerging class of gene therapy. IVT mRNA has several advantages over conventional pDNA for the expression of target proteins. mRNA does not require nuclear localization to mediate protein translation. The intracellular process for protein expression is much simpler and there is no potential risk of insertion mutagenesis. Having these advantages, the level of protein expression is far enhanced as comparable to that of viral expression systems. This makes IVT mRNA a powerful alternative gene expression system for various applications in regenerative medicine. In this review, we highlight the synthesis and preparation of IVT mRNA and its therapeutic applications. The article includes the design and preparation of IVT mRNA, chemical modification of IVT mRNA, and therapeutic applications of IVT mRNA in cellular reprogramming, stem cell engineering, and protein replacement therapy. Finally, future perspectives and challenges of IVT mRNA are discussed.
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Affiliation(s)
- Hyokyoung Kwon
- College of Pharmacy, Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Minjeong Kim
- College of Pharmacy, Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Yunmi Seo
- College of Pharmacy, Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Yae Seul Moon
- College of Pharmacy, Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Hwa Jeong Lee
- College of Pharmacy, Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Kyuri Lee
- College of Pharmacy, Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 03760, Republic of Korea.
| | - Hyukjin Lee
- College of Pharmacy, Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 03760, Republic of Korea.
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43
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Larson JD, Hoskins AA. Dynamics and consequences of spliceosome E complex formation. eLife 2017; 6:27592. [PMID: 28829039 PMCID: PMC5779234 DOI: 10.7554/elife.27592] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 08/21/2017] [Indexed: 12/26/2022] Open
Abstract
The spliceosome must identify the correct splice sites (SS) and branchsite (BS) used during splicing. E complex is the earliest spliceosome precursor in which the 5' SS and BS are defined. Definition occurs by U1 small nuclear ribonucleoprotein (snRNP) binding the 5' SS and recognition of the BS by the E complex protein (ECP) branchpoint bridging protein (BBP). We have used single molecule fluorescence to study Saccharomyces cerevisiae U1 and BBP interactions with RNAs. E complex is dynamic and permits frequent redefinition of the 5' SS and BS. BBP influences U1 binding at the 5' SS by promoting long-lived complex formation. ECPs facilitate U1 association with RNAs with weak 5' SS and prevent U1 accumulation on RNAs containing hyperstabilized 5' SS. The data reveal a mechanism for how U1 binds the 5' SS and suggest that E complex harnesses this mechanism to stimulate recruitment and retention of U1 on introns. Our genes contain coded instructions for making the molecules in our bodies, but this information must be extensively processed before it can be used. The instructions from each gene are first copied into a molecule called a pre-mRNA, before a process known as splicing removes certain sections to form a mature mRNA molecule. Splicing can remove different sections of the pre-mRNA to make different mRNA molecules from the same gene depending on the current needs of the cell. Splicing is controlled by a combination of proteins and other molecules, collectively called the spliceosome. A part of the spliceosome called U1 recognizes the start of pre-mRNA sections that need to be removed, which is referred to as the five-prime splice site (or “5’ SS” for short). The attachment of U1 to such a site allows other molecules to also attach to the pre-mRNA, which eventually assemble a spliceosome. The very first steps in this process involve U1 and a set of other proteins that create what is called the “Early” or “E” complex. Although there are many molecules involved in the E complex, it was not known how they interact with each other and how this affects which splice sites are used for splicing in different cells. Using advanced microscopy, Larson and Hoskins examined individual U1 molecules from yeast cells while the molecules formed E complexes and identified two different ways U1 can bind to five-prime splice sites. One process involved U1 attaching to pre-mRNA for a short time, whilst the other involved a longer association between U1 and pre-mRNA. Sometimes U1 could also transition between the first process and the second. The results showed that other parts of the E complex affected which process was used at different sites by affecting the type or duration of U1’s attachment. All U1 particles use the same components to attach to splice sites in all pre-mRNAs, but the most used splice sites are not always those that are predicted to have the strongest attachments to U1. This work helps to reveal how other proteins involved in splicing influence this effect, altering U1’s ability to attach to pre-mRNAs to suit each new situation. This also allows cells to change gene splicing to fit different situations. Many genes in our bodies rely on splicing and understanding this process in detail could be the key to diagnosing and treating a range of different illnesses.
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Affiliation(s)
- Joshua Donald Larson
- Department of Biochemistry, University of Wisconsin-Madison, Madison, United States.,Biophysics Graduate Program, University of Wisconsin-Madison, Madison, United States
| | - Aaron A Hoskins
- Department of Biochemistry, University of Wisconsin-Madison, Madison, United States.,Biophysics Graduate Program, University of Wisconsin-Madison, Madison, United States
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44
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Herzel L, Ottoz DSM, Alpert T, Neugebauer KM. Splicing and transcription touch base: co-transcriptional spliceosome assembly and function. Nat Rev Mol Cell Biol 2017; 18:637-650. [PMID: 28792005 DOI: 10.1038/nrm.2017.63] [Citation(s) in RCA: 225] [Impact Index Per Article: 32.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Several macromolecular machines collaborate to produce eukaryotic messenger RNA. RNA polymerase II (Pol II) translocates along genes that are up to millions of base pairs in length and generates a flexible RNA copy of the DNA template. This nascent RNA harbours introns that are removed by the spliceosome, which is a megadalton ribonucleoprotein complex that positions the distant ends of the intron into its catalytic centre. Emerging evidence that the catalytic spliceosome is physically close to Pol II in vivo implies that transcription and splicing occur on similar timescales and that the transcription and splicing machineries may be spatially constrained. In this Review, we discuss aspects of spliceosome assembly, transcription elongation and other co-transcriptional events that allow the temporal coordination of co-transcriptional splicing.
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Affiliation(s)
- Lydia Herzel
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520, USA.,Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Diana S M Ottoz
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520, USA
| | - Tara Alpert
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520, USA
| | - Karla M Neugebauer
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520, USA
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45
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Jiao X, Doamekpor SK, Bird JG, Nickels BE, Tong L, Hart RP, Kiledjian M. 5' End Nicotinamide Adenine Dinucleotide Cap in Human Cells Promotes RNA Decay through DXO-Mediated deNADding. Cell 2017; 168:1015-1027.e10. [PMID: 28283058 DOI: 10.1016/j.cell.2017.02.019] [Citation(s) in RCA: 148] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 12/09/2016] [Accepted: 02/09/2017] [Indexed: 02/02/2023]
Abstract
Eukaryotic mRNAs generally possess a 5' end N7 methyl guanosine (m7G) cap that promotes their translation and stability. However, mammalian mRNAs can also carry a 5' end nicotinamide adenine dinucleotide (NAD+) cap that, in contrast to the m7G cap, does not support translation but instead promotes mRNA decay. The mammalian and fungal noncanonical DXO/Rai1 decapping enzymes efficiently remove NAD+ caps, and cocrystal structures of DXO/Rai1 with 3'-NADP+ illuminate the molecular mechanism for how the "deNADding" reaction produces NAD+ and 5' phosphate RNA. Removal of DXO from cells increases NAD+-capped mRNA levels and enables detection of NAD+-capped intronic small nucleolar RNAs (snoRNAs), suggesting NAD+ caps can be added to 5'-processed termini. Our findings establish NAD+ as an alternative mammalian RNA cap and DXO as a deNADding enzyme modulating cellular levels of NAD+-capped RNAs. Collectively, these data reveal that mammalian RNAs can harbor a 5' end modification distinct from the classical m7G cap that promotes rather than inhibits RNA decay.
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Affiliation(s)
- Xinfu Jiao
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ 08854, USA
| | - Selom K Doamekpor
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Jeremy G Bird
- Department of Genetics and Waksman Institute, Rutgers University, Piscataway, NJ 08854, USA
| | - Bryce E Nickels
- Department of Genetics and Waksman Institute, Rutgers University, Piscataway, NJ 08854, USA
| | - Liang Tong
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Ronald P Hart
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ 08854, USA
| | - Megerditch Kiledjian
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ 08854, USA.
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46
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Identification of NAD+ capped mRNAs in Saccharomyces cerevisiae. Proc Natl Acad Sci U S A 2016; 114:480-485. [PMID: 28031484 DOI: 10.1073/pnas.1619369114] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
RNAs besides tRNA and rRNA contain chemical modifications, including the recently described 5' nicotinamide-adenine dinucleotide (NAD+) RNA in bacteria. Whether 5' NAD-RNA exists in eukaryotes remains unknown. We demonstrate that 5' NAD-RNA is found on subsets of nuclear and mitochondrial encoded mRNAs in Saccharomyces cerevisiae NAD-mRNA appears to be produced cotranscriptionally because NAD-RNA is also found on pre-mRNAs, and only on mitochondrial transcripts that are not 5' end processed. These results define an additional 5' RNA cap structure in eukaryotes and raise the possibility that this 5' NAD+ cap could modulate RNA stability and translation on specific subclasses of mRNAs.
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47
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Fuchs AL, Neu A, Sprangers R. A general method for rapid and cost-efficient large-scale production of 5' capped RNA. RNA (NEW YORK, N.Y.) 2016; 22:1454-66. [PMID: 27368341 PMCID: PMC4986899 DOI: 10.1261/rna.056614.116] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 05/25/2016] [Indexed: 05/03/2023]
Abstract
The eukaryotic mRNA 5' cap structure is indispensible for pre-mRNA processing, mRNA export, translation initiation, and mRNA stability. Despite this importance, structural and biophysical studies that involve capped RNA are challenging and rare due to the lack of a general method to prepare mRNA in sufficient quantities. Here, we show that the vaccinia capping enzyme can be used to produce capped RNA in the amounts that are required for large-scale structural studies. We have therefore designed an efficient expression and purification protocol for the vaccinia capping enzyme. Using this approach, the reaction scale can be increased in a cost-efficient manner, where the yields of the capped RNA solely depend on the amount of available uncapped RNA target. Using a large number of RNA substrates, we show that the efficiency of the capping reaction is largely independent of the sequence, length, and secondary structure of the RNA, which makes our approach generally applicable. We demonstrate that the capped RNA can be directly used for quantitative biophysical studies, including fluorescence anisotropy and high-resolution NMR spectroscopy. In combination with (13)C-methyl-labeled S-adenosyl methionine, the methyl groups in the RNA can be labeled for methyl TROSY NMR spectroscopy. Finally, we show that our approach can produce both cap-0 and cap-1 RNA in high amounts. In summary, we here introduce a general and straightforward method that opens new means for structural and functional studies of proteins and enzymes in complex with capped RNA.
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Affiliation(s)
- Anna-Lisa Fuchs
- Max Planck Institute for Developmental Biology, 72076 Tübingen, Germany
| | - Ancilla Neu
- Max Planck Institute for Developmental Biology, 72076 Tübingen, Germany
| | - Remco Sprangers
- Max Planck Institute for Developmental Biology, 72076 Tübingen, Germany
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48
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Grudzien-Nogalska E, Kiledjian M. New insights into decapping enzymes and selective mRNA decay. WILEY INTERDISCIPLINARY REVIEWS-RNA 2016; 8. [PMID: 27425147 DOI: 10.1002/wrna.1379] [Citation(s) in RCA: 104] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 06/23/2016] [Accepted: 06/27/2016] [Indexed: 01/04/2023]
Abstract
Removal of the 5' end cap is a critical determinant controlling mRNA stability and efficient gene expression. Removal of the cap is exquisitely controlled by multiple direct and indirect regulators that influence association with the cap and the catalytic step. A subset of these factors directly stimulate activity of the decapping enzyme, while others influence remodeling of factors bound to mRNA and indirectly stimulate decapping. Furthermore, the components of the general decapping machinery can also be recruited by mRNA-specific regulatory proteins to activate decapping. The Nudix hydrolase, Dcp2, identified as a first decapping enzyme, cleaves capped mRNA and initiates 5'-3' degradation. Extensive studies on Dcp2 led to broad understanding of its activity and the regulation of transcript specific decapping and decay. Interestingly, seven additional Nudix proteins possess intrinsic decapping activity in vitro and at least two, Nudt16 and Nudt3, are decapping enzymes that regulate mRNA stability in cells. Furthermore, a new class of decapping proteins within the DXO family preferentially function on incompletely capped mRNAs. Importantly, it is now evident that each of the characterized decapping enzymes predominantly modulates only a subset of mRNAs, suggesting the existence of multiple decapping enzymes functioning in distinct cellular pathways. WIREs RNA 2017, 8:e1379. doi: 10.1002/wrna.1379 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Ewa Grudzien-Nogalska
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ, USA
| | - Megerditch Kiledjian
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ, USA
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49
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Ramanathan A, Robb GB, Chan SH. mRNA capping: biological functions and applications. Nucleic Acids Res 2016; 44:7511-26. [PMID: 27317694 PMCID: PMC5027499 DOI: 10.1093/nar/gkw551] [Citation(s) in RCA: 458] [Impact Index Per Article: 57.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 06/03/2016] [Indexed: 12/19/2022] Open
Abstract
The 5′ m7G cap is an evolutionarily conserved modification of eukaryotic mRNA. Decades of research have established that the m7G cap serves as a unique molecular module that recruits cellular proteins and mediates cap-related biological functions such as pre-mRNA processing, nuclear export and cap-dependent protein synthesis. Only recently has the role of the cap 2′O methylation as an identifier of self RNA in the innate immune system against foreign RNA has become clear. The discovery of the cytoplasmic capping machinery suggests a novel level of control network. These new findings underscore the importance of a proper cap structure in the synthesis of functional messenger RNA. In this review, we will summarize the current knowledge of the biological roles of mRNA caps in eukaryotic cells. We will also discuss different means that viruses and their host cells use to cap their RNA and the application of these capping machineries to synthesize functional mRNA. Novel applications of RNA capping enzymes in the discovery of new RNA species and sequencing the microbiome transcriptome will also be discussed. We will end with a summary of novel findings in RNA capping and the questions these findings pose.
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Affiliation(s)
- Anand Ramanathan
- New England Biolabs, Inc. 240 County Road, Ipswich, MA 01938, USA
| | - G Brett Robb
- New England Biolabs, Inc. 240 County Road, Ipswich, MA 01938, USA
| | - Siu-Hong Chan
- New England Biolabs, Inc. 240 County Road, Ipswich, MA 01938, USA
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50
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Gromadzka AM, Steckelberg AL, Singh KK, Hofmann K, Gehring NH. A short conserved motif in ALYREF directs cap- and EJC-dependent assembly of export complexes on spliced mRNAs. Nucleic Acids Res 2016; 44:2348-61. [PMID: 26773052 PMCID: PMC4797287 DOI: 10.1093/nar/gkw009] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 01/04/2016] [Indexed: 02/05/2023] Open
Abstract
The export of messenger RNAs (mRNAs) is the final of several nuclear posttranscriptional steps of gene expression. The formation of export-competent mRNPs involves the recruitment of export factors that are assumed to facilitate transport of the mature mRNAs. Using in vitro splicing assays, we show that a core set of export factors, including ALYREF, UAP56 and DDX39, readily associate with the spliced RNAs in an EJC (exon junction complex)- and cap-dependent manner. In order to elucidate how ALYREF and other export adaptors mediate mRNA export, we conducted a computational analysis and discovered four short, conserved, linear motifs present in RNA-binding proteins. We show that mutation in one of the new motifs (WxHD) in an unstructured region of ALYREF reduced RNA binding and abolished the interaction with eIF4A3 and CBP80. Additionally, the mutation impaired proper localization to nuclear speckles and export of a spliced reporter mRNA. Our results reveal important details of the orchestrated recruitment of export factors during the formation of export competent mRNPs.
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Affiliation(s)
| | | | - Kusum K Singh
- Institute for Genetics, University of Cologne, D-50674 Cologne, Germany
| | - Kay Hofmann
- Institute for Genetics, University of Cologne, D-50674 Cologne, Germany
| | - Niels H Gehring
- Institute for Genetics, University of Cologne, D-50674 Cologne, Germany
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