1
|
Tian L, Zhao Z, Gao W, Liu Z, Li X, Zhang W, Li Z. SARS-CoV-2 nsp16 is regulated by host E3 ubiquitin ligases, UBR5 and MARCHF7. eLife 2025; 13:RP102277. [PMID: 40358464 PMCID: PMC12074641 DOI: 10.7554/elife.102277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2025] Open
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), remains a global public health threat with considerable economic consequences. The nonstructural protein 16 (nsp16), in complex with nsp10, facilitates the final viral mRNA capping step through its 2'-O-methylase activity, helping the virus to evade host immunity and prevent mRNA degradation. However, nsp16 regulation by host factors remains poorly understood. While various E3 ubiquitin ligases interact with SARS-CoV-2 proteins, their roles in targeting nsp16 for degradation remain unclear. In this study, we demonstrate that nsp16 undergoes ubiquitination and proteasomal degradation mediated by the host E3 ligases UBR5 and MARCHF7. UBR5 induces K48-linked ubiquitination, whereas MARCHF7 promotes K27-linked ubiquitination, independently suppressing SARS-CoV-2 replication in cell cultures and in mice. Notably, UBR5 and MARCHF7 also degrade nsp16 variants from different viral strains, exhibiting broad-spectrum antiviral activity. Our findings reveal novel antiviral mechanisms of the ubiquitin-proteasome system (UPS) and highlight their potential therapeutic targets against COVID-19.
Collapse
Affiliation(s)
- Li Tian
- Department of Infectious Diseases, Infectious Diseases and Pathogen Biology Center, Institute of Virology and AIDS Research, Key Laboratory of Organ Regeneration and Transplantation of The Ministry of Education, The First Hospital of Jilin UniversityChangchunChina
| | - Zongzheng Zhao
- Research Unit of Key Technologies for Prevention and Control of Virus Zoonoses, Chinese Academy of Medical Sciences, Changchun Veterinary Research Institute, Chinese Academy of Agricultural SciencesChangchunChina
| | - Wenying Gao
- Department of Infectious Diseases, Infectious Diseases and Pathogen Biology Center, Institute of Virology and AIDS Research, Key Laboratory of Organ Regeneration and Transplantation of The Ministry of Education, The First Hospital of Jilin UniversityChangchunChina
| | - Zirui Liu
- Research Unit of Key Technologies for Prevention and Control of Virus Zoonoses, Chinese Academy of Medical Sciences, Changchun Veterinary Research Institute, Chinese Academy of Agricultural SciencesChangchunChina
| | - Xiao Li
- Research Unit of Key Technologies for Prevention and Control of Virus Zoonoses, Chinese Academy of Medical Sciences, Changchun Veterinary Research Institute, Chinese Academy of Agricultural SciencesChangchunChina
| | - Wenyan Zhang
- Department of Infectious Diseases, Infectious Diseases and Pathogen Biology Center, Institute of Virology and AIDS Research, Key Laboratory of Organ Regeneration and Transplantation of The Ministry of Education, The First Hospital of Jilin UniversityChangchunChina
| | - Zhaolong Li
- Department of Infectious Diseases, Infectious Diseases and Pathogen Biology Center, Institute of Virology and AIDS Research, Key Laboratory of Organ Regeneration and Transplantation of The Ministry of Education, The First Hospital of Jilin UniversityChangchunChina
| |
Collapse
|
2
|
Su N, Yu X, Duan M, Shi N. Recent advances in methylation modifications of microRNA. Genes Dis 2025; 12:101201. [PMID: 39524539 PMCID: PMC11550756 DOI: 10.1016/j.gendis.2023.101201] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 11/13/2023] [Accepted: 11/19/2023] [Indexed: 11/16/2024] Open
Abstract
microRNAs (miRNAs) are short single-stranded non-coding RNAs between 21 and 25 nt in length in eukaryotic organisms, which control post-transcriptional gene expression. Through complementary base pairing, miRNAs generally bind to their target messenger RNAs and repress protein production by destabilizing the messenger RNA and translational silencing. They regulate almost all life activities, such as cell proliferation, differentiation, apoptosis, tumorigenesis, and host-pathogen interactions. Methylation modification is the most common RNA modification in eukaryotes. miRNA methylation exists in different types, mainly N6-methyladenosine, 5-methylcytosine, and 7-methylguanine, which can change the expression level and biological mode of action of miRNAs and improve the activity of regulating gene expression in a very fine-tuned way with flexibility. In this review, we will summarize the recent findings concerning methylation modifications of miRNA, focusing on their biogenesis and the potential role of miRNA fate and functions.
Collapse
Affiliation(s)
| | | | | | - Ning Shi
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, Jilin 130062, China
| |
Collapse
|
3
|
Wang Y, Guo H, Lu Y, Yang W, Li T, Ji X. Crystal structure and nucleic acid binding mode of CPV NSP9: implications for viroplasm in Reovirales. Nucleic Acids Res 2024; 52:11115-11127. [PMID: 39287123 PMCID: PMC11472163 DOI: 10.1093/nar/gkae803] [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: 06/05/2024] [Revised: 08/28/2024] [Accepted: 09/03/2024] [Indexed: 09/19/2024] Open
Abstract
Cytoplasmic polyhedrosis viruses (CPVs), like other members of the order Reovirales, produce viroplasms, hubs of viral assembly that shield them from host immunity. Our study investigates the potential role of NSP9, a nucleic acid-binding non-structural protein encoded by CPVs, in viroplasm biogenesis. We determined the crystal structure of the NSP9 core (NSP9ΔC), which shows a dimeric organization topologically similar to the P9-1 homodimers of plant reoviruses. The disordered C-terminal region of NSP9 facilitates oligomerization but is dispensable for nucleic acid binding. NSP9 robustly binds to single- and double-stranded nucleic acids, regardless of RNA or DNA origin. Mutagenesis studies further confirmed that the dimeric form of NSP9 is critical for nucleic acid binding due to positively charged residues that form a tunnel during homodimerization. Gel migration assays reveal a unique nucleic acid binding pattern, with the sequential appearance of two distinct complexes dependent on protein concentration. The similar gel migration pattern shared by NSP9 and rotavirus NSP3, coupled with its structural resemblance to P9-1, hints at a potential role in translational regulation or viral genome packaging, which may be linked to viroplasm. This study advances our understanding of viroplasm biogenesis and Reovirales replication, providing insights into potential antiviral drug targets.
Collapse
Affiliation(s)
- Yeda Wang
- Department of Infectious Diseases, Nanjing Drum Tower Hospital, State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Institute of Viruses and Infectious Diseases, Chemistry and Biomedicine Innovation Center (ChemBIC), Institute of Artificial Intelligence Biomedicine, Nanjing University, Nanjing, China
| | - Hangtian Guo
- Department of Infectious Diseases, Nanjing Drum Tower Hospital, State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Institute of Viruses and Infectious Diseases, Chemistry and Biomedicine Innovation Center (ChemBIC), Institute of Artificial Intelligence Biomedicine, Nanjing University, Nanjing, China
| | - Yuhao Lu
- Department of Infectious Diseases, Nanjing Drum Tower Hospital, State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Institute of Viruses and Infectious Diseases, Chemistry and Biomedicine Innovation Center (ChemBIC), Institute of Artificial Intelligence Biomedicine, Nanjing University, Nanjing, China
| | - Wanbin Yang
- Department of Infectious Diseases, Nanjing Drum Tower Hospital, State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Institute of Viruses and Infectious Diseases, Chemistry and Biomedicine Innovation Center (ChemBIC), Institute of Artificial Intelligence Biomedicine, Nanjing University, Nanjing, China
| | - Tinghan Li
- Department of Infectious Diseases, Nanjing Drum Tower Hospital, State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Institute of Viruses and Infectious Diseases, Chemistry and Biomedicine Innovation Center (ChemBIC), Institute of Artificial Intelligence Biomedicine, Nanjing University, Nanjing, China
| | - Xiaoyun Ji
- Department of Infectious Diseases, Nanjing Drum Tower Hospital, State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Institute of Viruses and Infectious Diseases, Chemistry and Biomedicine Innovation Center (ChemBIC), Institute of Artificial Intelligence Biomedicine, Nanjing University, Nanjing, China
- Engineering Research Center of Protein and Peptide Medicine, Ministry of Education, China
| |
Collapse
|
4
|
Tsukamoto Y, Igarashi M, Kato H. Targeting cap1 RNA methyltransferases as an antiviral strategy. Cell Chem Biol 2024; 31:86-99. [PMID: 38091983 DOI: 10.1016/j.chembiol.2023.11.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 10/30/2023] [Accepted: 11/20/2023] [Indexed: 01/21/2024]
Abstract
Methylation is one of the critical modifications that regulates numerous biological processes. Guanine capping and methylation at the 7th position (m7G) have been shown to mature mRNA for increased RNA stability and translational efficiency. The m7G capped cap0 RNA remains immature and requires additional methylation at the first nucleotide (N1-2'-O-Me), designated as cap1, to achieve full maturation. This cap1 RNA with N1-2'-O-Me prevents its recognition by innate immune sensors as non-self. Viruses have also evolved various strategies to produce self-like capped RNAs with the N1-2'-O-Me that potentially evades the antiviral response and establishes an efficient replication. In this review, we focus on the importance of the presence of N1-2'-O-Me in viral RNAs and discuss the potential for drug development by targeting host and viral N1-2'-O-methyltransferases.
Collapse
Affiliation(s)
- Yuta Tsukamoto
- Institute of Cardiovascular Immunology, Medical Faculty, University Hospital Bonn, University of Bonn, Bonn, Germany
| | - Manabu Igarashi
- Division of Global Epidemiology, International Institute for Zoonosis Control, Hokkaido University, Sapporo, Japan; International Collaboration Unit, International Institute for Zoonosis Control, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Hiroki Kato
- Institute of Cardiovascular Immunology, Medical Faculty, University Hospital Bonn, University of Bonn, Bonn, Germany.
| |
Collapse
|
5
|
Inagaki M. Cell Reprogramming and Differentiation Utilizing Messenger RNA for Regenerative Medicine. J Dev Biol 2023; 12:1. [PMID: 38535481 PMCID: PMC10971469 DOI: 10.3390/jdb12010001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 12/06/2023] [Accepted: 12/19/2023] [Indexed: 06/16/2024] Open
Abstract
The COVID-19 pandemic generated interest in the medicinal applications of messenger RNA (mRNA). It is expected that mRNA will be applied, not only to vaccines, but also to regenerative medicine. The purity of mRNA is important for its medicinal applications. However, the current mRNA synthesis techniques exhibit problems, including the contamination of undesired 5'-uncapped mRNA and double-stranded RNA. Recently, our group developed a completely capped mRNA synthesis technology that contributes to the progress of mRNA research. The introduction of chemically modified nucleosides, such as N1-methylpseudouridine and 5-methylcytidine, has been reported by Karikó and Weissman, opening a path for the practical application of mRNA for vaccines and regenerative medicine. Yamanaka reported the production of induced pluripotent stem cells (iPSCs) by introducing four types of genes using a retrovirus vector. iPSCs are widely used for research on regenerative medicine and the preparation of disease models to screen new drug candidates. Among the Yamanaka factors, Klf4 and c-Myc are oncogenes, and there is a risk of tumor development if these are integrated into genomic DNA. Therefore, regenerative medicine using mRNA, which poses no risk of genome insertion, has attracted attention. In this review, the author summarizes techniques for synthesizing mRNA and its application in regenerative medicine.
Collapse
Affiliation(s)
- Masahito Inagaki
- Graduate School of Science, Nagoya University, Nagoya 464-8602, Japan
| |
Collapse
|
6
|
Shao X, Zhang H, Zhu Z, Ji F, He Z, Yang Z, Xia Y, Cai Z. DpCoA tagSeq: Barcoding dpCoA-Capped RNA for Direct Nanopore Sequencing via Maleimide-Thiol Reaction. Anal Chem 2023; 95:11124-11131. [PMID: 37439785 PMCID: PMC10372868 DOI: 10.1021/acs.analchem.3c02063] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 06/27/2023] [Indexed: 07/14/2023]
Abstract
Recent discoveries of noncanonical RNA caps, such as nicotinamide adenine dinucleotide (NAD+) and 3'-dephospho-coenzyme A (dpCoA), have expanded our knowledge of RNA caps. Although dpCoA has been known to cap RNAs in various species, the identities of its capped RNAs (dpCoA-RNAs) remained unknown. To fill this gap, we developed a method called dpCoA tagSeq, which utilized a thiol-reactive maleimide group to label dpCoA cap with a tag RNA serving as the 5' barcode. The barcoded RNAs were isolated using a complementary DNA strand of the tag RNA prior to direct sequencing by nanopore technology. Our validation experiments with model RNAs showed that dpCoA-RNA was efficiently tagged and captured using this protocol. To confirm that the tagged RNAs are capped by dpCoA and no other thiol-containing molecules, we used a pyrophosphatase NudC to degrade the dpCoA cap to adenosine monophosphate (AMP) moiety before performing the tagSeq protocol. We identified 44 genes that transcribe dpCoA-RNAs in mouse liver, demonstrating the method's effectiveness in identifying and characterizing the capped RNAs. This strategy provides a viable approach to identifying dpCoA-RNAs that allows for further functional investigations of the cap.
Collapse
Affiliation(s)
- Xiaojian Shao
- State
Key Laboratory of Environmental and Biological Analysis, Department
of Chemistry, Hong Kong Baptist University, Hong Kong, China
| | - Hailei Zhang
- Department
of Biology, Hong Kong Baptist University, Hong Kong, China
| | - Zhou Zhu
- School
of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China
| | - Fenfen Ji
- State
Key Laboratory of Environmental and Biological Analysis, Department
of Chemistry, Hong Kong Baptist University, Hong Kong, China
| | - Zhao He
- State
Key Laboratory of Environmental and Biological Analysis, Department
of Chemistry, Hong Kong Baptist University, Hong Kong, China
| | - Zhu Yang
- State
Key Laboratory of Environmental and Biological Analysis, Department
of Chemistry, Hong Kong Baptist University, Hong Kong, China
| | - Yiji Xia
- Department
of Biology, Hong Kong Baptist University, Hong Kong, China
| | - Zongwei Cai
- State
Key Laboratory of Environmental and Biological Analysis, Department
of Chemistry, Hong Kong Baptist University, Hong Kong, China
| |
Collapse
|
7
|
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: 9] [Impact Index Per Article: 4.5] [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.
Collapse
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.
| |
Collapse
|
8
|
Seo JJ, Jung SJ, Yang J, Choi DE, Kim VN. Functional viromic screens uncover regulatory RNA elements. Cell 2023:S0092-8674(23)00675-X. [PMID: 37413987 DOI: 10.1016/j.cell.2023.06.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Revised: 04/21/2023] [Accepted: 06/10/2023] [Indexed: 07/08/2023]
Abstract
The number of sequenced viral genomes has surged recently, presenting an opportunity to understand viral diversity and uncover unknown regulatory mechanisms. Here, we conducted a screening of 30,367 viral segments from 143 species representing 96 genera and 37 families. Using a library of viral segments in 3' UTR, we identified hundreds of elements impacting RNA abundance, translation, and nucleocytoplasmic distribution. To illustrate the power of this approach, we investigated K5, an element conserved in kobuviruses, and found its potent ability to enhance mRNA stability and translation in various contexts, including adeno-associated viral vectors and synthetic mRNAs. Moreover, we identified a previously uncharacterized protein, ZCCHC2, as a critical host factor for K5. ZCCHC2 recruits the terminal nucleotidyl transferase TENT4 to elongate poly(A) tails with mixed sequences, delaying deadenylation. This study provides a unique resource for virus and RNA research and highlights the potential of the virosphere for biological discoveries.
Collapse
Affiliation(s)
- Jenny J Seo
- Center for RNA Research, Institute for Basic Science, Seoul 08826, Republic of Korea; School of Biological Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Soo-Jin Jung
- Center for RNA Research, Institute for Basic Science, Seoul 08826, Republic of Korea; School of Biological Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Jihye Yang
- Center for RNA Research, Institute for Basic Science, Seoul 08826, Republic of Korea; School of Biological Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Da-Eun Choi
- Center for RNA Research, Institute for Basic Science, Seoul 08826, Republic of Korea; School of Biological Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - V Narry Kim
- Center for RNA Research, Institute for Basic Science, Seoul 08826, Republic of Korea; School of Biological Sciences, Seoul National University, Seoul 08826, Republic of Korea.
| |
Collapse
|
9
|
Park GJ, Osinski A, Hernandez G, Eitson JL, Majumdar A, Tonelli M, Henzler-Wildman K, Pawłowski K, Chen Z, Li Y, Schoggins JW, Tagliabracci VS. The mechanism of RNA capping by SARS-CoV-2. Nature 2022; 609:793-800. [PMID: 35944563 PMCID: PMC9492545 DOI: 10.1038/s41586-022-05185-z] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 08/03/2022] [Indexed: 11/29/2022]
Abstract
The RNA genome of SARS-CoV-2 contains a 5′ cap that facilitates the translation of viral proteins, protection from exonucleases and evasion of the host immune response1–4. How this cap is made in SARS-CoV-2 is not completely understood. Here we reconstitute the N7- and 2′-O-methylated SARS-CoV-2 RNA cap (7MeGpppA2′-O-Me) using virally encoded non-structural proteins (nsps). We show that the kinase-like nidovirus RdRp-associated nucleotidyltransferase (NiRAN) domain5 of nsp12 transfers the RNA to the amino terminus of nsp9, forming a covalent RNA–protein intermediate (a process termed RNAylation). Subsequently, the NiRAN domain transfers the RNA to GDP, forming the core cap structure GpppA-RNA. The nsp146 and nsp167 methyltransferases then add methyl groups to form functional cap structures. Structural analyses of the replication–transcription complex bound to nsp9 identified key interactions that mediate the capping reaction. Furthermore, we demonstrate in a reverse genetics system8 that the N terminus of nsp9 and the kinase-like active-site residues in the NiRAN domain are required for successful SARS-CoV-2 replication. Collectively, our results reveal an unconventional mechanism by which SARS-CoV-2 caps its RNA genome, thus exposing a new target in the development of antivirals to treat COVID-19. Reconstitution of the SARS-CoV-2 RNA 5′ cap reveals the unconventional mechanism by which SARS-CoV-2 caps its RNA genome, providing a new target in the development of antiviral agents to treat COVID-19.
Collapse
Affiliation(s)
- Gina J Park
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Adam Osinski
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Genaro Hernandez
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Jennifer L Eitson
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Abir Majumdar
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Marco Tonelli
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, USA
| | | | - Krzysztof Pawłowski
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Department of Biochemistry and Microbiology, Institute of Biology, Warsaw University of Life Sciences, Warsaw, Poland
| | - Zhe Chen
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Yang Li
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - John W Schoggins
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Vincent S Tagliabracci
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA. .,Harold C. Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, Texas, USA. .,Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA. .,Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, Texas, USA.
| |
Collapse
|
10
|
Stenglein MD. The Case for Studying New Viruses of New Hosts. Annu Rev Virol 2022; 9:157-172. [PMID: 35671564 DOI: 10.1146/annurev-virology-100220-112915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Virology has largely focused on viruses that are pathogenic to humans or to the other species that we care most about. There is no doubt that this has been a worthwhile investment. But many transformative advances have been made through the in-depth study of relatively obscure viruses that do not appear on lists of prioritized pathogens. In this review, I highlight the benefits that can accrue from the study of viruses and hosts off the beaten track. I take stock of viral sequence diversity across host taxa as an estimate of the bias that exists in our understanding of host-virus interactions. I describe the gains that have been made through the metagenomic discovery of thousands of new viruses in previously unsampled hosts as well as the limitations of metagenomic surveys. I conclude by suggesting that the study of viruses that naturally infect existing and emerging model organisms represents an opportunity to push virology forward in useful and hard to predict ways.Expected final online publication date for the Annual Review of Virology, Volume 9 is September 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
Collapse
Affiliation(s)
- Mark D Stenglein
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA;
| |
Collapse
|
11
|
Cai T, Atteh LL, Zhang X, Huang C, Bai M, Ma H, Zhang C, Fu W, Gao L, Lin Y, Meng W. The N6-Methyladenosine Modification and Its Role in mRNA Metabolism and Gastrointestinal Tract Disease. Front Surg 2022; 9:819335. [PMID: 35155557 PMCID: PMC8831730 DOI: 10.3389/fsurg.2022.819335] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Accepted: 01/10/2022] [Indexed: 11/13/2022] Open
Abstract
The N6-methyladenosine (m6A) modification is the most abundant internal modification of messenger RNA (mRNA) in higher eukaryotes. Under the actions of methyltransferase, demethylase and methyl-binding protein, m6A resulting from RNA methylation becomes dynamic and reversible, similar to that from DNA methylation, and this effect allows the generated mRNA to participate in metabolism processes, such as splicing, transport, translation, and degradation. The most common tumors are those found in the gastrointestinal tract, and research on these tumors has flourished since the discovery of m6A. Overall, further analysis of the mechanism of m6A and its role in tumors may contribute to new ideas for the treatment of tumors. m6A also plays an important role in non-tumor diseases of the gastrointestinal tract. This manuscript reviews the current knowledge of m6A-related proteins, mRNA metabolism and their application in gastrointestinal tract disease.
Collapse
Affiliation(s)
- Teng Cai
- The First Clinical Medical College, Lanzhou University, Lanzhou, China
- Gansu Province Key Laboratory Biotherapy and Regenerative Medicine, Lanzhou, China
| | | | - Xianzhuo Zhang
- The First Clinical Medical College, Lanzhou University, Lanzhou, China
| | - Chongfei Huang
- The First Clinical Medical College, Lanzhou University, Lanzhou, China
| | - Mingzhen Bai
- The First Clinical Medical College, Lanzhou University, Lanzhou, China
| | - Haidong Ma
- The First Clinical Medical College, Lanzhou University, Lanzhou, China
| | - Chao Zhang
- The First Clinical Medical College, Lanzhou University, Lanzhou, China
| | - Wenkang Fu
- The First Clinical Medical College, Lanzhou University, Lanzhou, China
| | - Long Gao
- The First Clinical Medical College, Lanzhou University, Lanzhou, China
| | - Yanyan Lin
- The Department of General Surgery, The First Hospital of Lanzhou University, Lanzhou, China
- Gansu Province Institute of Hepatopancreatobiliary Surgery, Lanzhou, China
- Yanyan Lin
| | - Wenbo Meng
- The First Clinical Medical College, Lanzhou University, Lanzhou, China
- The Department of General Surgery, The First Hospital of Lanzhou University, Lanzhou, China
- Gansu Province Institute of Hepatopancreatobiliary Surgery, Lanzhou, China
- *Correspondence: Wenbo Meng
| |
Collapse
|
12
|
Kaiser S, Byrne SR, Ammann G, Asadi Atoi P, Borland K, Brecheisen R, DeMott MS, Gehrke T, Hagelskamp F, Heiss M, Yoluç Y, Liu L, Zhang Q, Dedon PC, Cao B, Kellner S. Strategien zur Vermeidung von Artefakten in der massenspektrometrischen Epitranskriptomanalytik. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202106215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Steffen Kaiser
- Ludwig-Maximilians Universität München Butenandtstr. 5–13 81137 München Deutschland
- Institut für Pharmazeutische Chemie Goethe-Universität Frankfurt Max-von-Laue-Str. 9 60438 Frankfurt Deutschland
| | - Shane R. Byrne
- Department of Biological Engineering and Center for Environmental Health Sciences Massachusetts Institute of Technology Cambridge MA 02139 USA
| | - Gregor Ammann
- Ludwig-Maximilians Universität München Butenandtstr. 5–13 81137 München Deutschland
| | - Paria Asadi Atoi
- Ludwig-Maximilians Universität München Butenandtstr. 5–13 81137 München Deutschland
| | - Kayla Borland
- Ludwig-Maximilians Universität München Butenandtstr. 5–13 81137 München Deutschland
| | | | - Michael S. DeMott
- Department of Biological Engineering and Center for Environmental Health Sciences Massachusetts Institute of Technology Cambridge MA 02139 USA
| | - Tim Gehrke
- Ella Biotech GmbH 82152 München Deutschland
| | - Felix Hagelskamp
- Ludwig-Maximilians Universität München Butenandtstr. 5–13 81137 München Deutschland
| | - Matthias Heiss
- Ludwig-Maximilians Universität München Butenandtstr. 5–13 81137 München Deutschland
| | - Yasemin Yoluç
- Ludwig-Maximilians Universität München Butenandtstr. 5–13 81137 München Deutschland
| | - Lili Liu
- College of Life Sciences Qufu Normal University Qufu Shandong 273165 China
| | - Qinghua Zhang
- College of Life Sciences Qufu Normal University Qufu Shandong 273165 China
| | - Peter C. Dedon
- Department of Biological Engineering and Center for Environmental Health Sciences Massachusetts Institute of Technology Cambridge MA 02139 USA
- Antimicrobial Resistance Interdisciplinary Research Group Singapore-Massachusetts Institute of Technology Alliance for Research and Technology 138602 Singapore Singapur
| | - Bo Cao
- College of Life Sciences Qufu Normal University Qufu Shandong 273165 China
| | - Stefanie Kellner
- Ludwig-Maximilians Universität München Butenandtstr. 5–13 81137 München Deutschland
- Institut für Pharmazeutische Chemie Goethe-Universität Frankfurt Max-von-Laue-Str. 9 60438 Frankfurt Deutschland
| |
Collapse
|
13
|
Kaiser S, Byrne SR, Ammann G, Asadi Atoi P, Borland K, Brecheisen R, DeMott MS, Gehrke T, Hagelskamp F, Heiss M, Yoluç Y, Liu L, Zhang Q, Dedon PC, Cao B, Kellner S. Strategies to Avoid Artifacts in Mass Spectrometry-Based Epitranscriptome Analyses. Angew Chem Int Ed Engl 2021; 60:23885-23893. [PMID: 34339593 PMCID: PMC8597057 DOI: 10.1002/anie.202106215] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Indexed: 11/05/2022]
Abstract
In this report, we perform structure validation of recently reported RNA phosphorothioate (PT) modifications, a new set of epitranscriptome marks found in bacteria and eukaryotes including humans. By comparing synthetic PT-containing diribonucleotides with native species in RNA hydrolysates by high-resolution mass spectrometry (MS), metabolic stable isotope labeling, and PT-specific iodine-desulfurization, we disprove the existence of PTs in RNA from E. coli, S. cerevisiae, human cell lines, and mouse brain. Furthermore, we discuss how an MS artifact led to the initial misidentification of 2'-O-methylated diribonucleotides as RNA phosphorothioates. To aid structure validation of new nucleic acid modifications, we present a detailed guideline for MS analysis of RNA hydrolysates, emphasizing how the chosen RNA hydrolysis protocol can be a decisive factor in discovering and quantifying RNA modifications in biological samples.
Collapse
Affiliation(s)
- Steffen Kaiser
- Ludwig-Maximilians Universität MünchenButenandtstr. 5–1381137MünchenDeutschland
- Institute of Pharmaceutical ChemistryGoethe-University FrankfurtMax-von-Laue-Str. 960438FrankfurtGermany
| | - Shane R. Byrne
- Department of Biological Engineering and Center for Environmental Health SciencesMassachusetts Institute of TechnologyCambridgeMA02139USA
| | - Gregor Ammann
- Ludwig-Maximilians Universität MünchenButenandtstr. 5–1381137MünchenDeutschland
| | - Paria Asadi Atoi
- Ludwig-Maximilians Universität MünchenButenandtstr. 5–1381137MünchenDeutschland
| | - Kayla Borland
- Ludwig-Maximilians Universität MünchenButenandtstr. 5–1381137MünchenDeutschland
| | | | - Michael S. DeMott
- Department of Biological Engineering and Center for Environmental Health SciencesMassachusetts Institute of TechnologyCambridgeMA02139USA
| | | | - Felix Hagelskamp
- Ludwig-Maximilians Universität MünchenButenandtstr. 5–1381137MünchenDeutschland
| | - Matthias Heiss
- Ludwig-Maximilians Universität MünchenButenandtstr. 5–1381137MünchenDeutschland
| | - Yasemin Yoluç
- Ludwig-Maximilians Universität MünchenButenandtstr. 5–1381137MünchenDeutschland
| | - Lili Liu
- College of Life SciencesQufu Normal UniversityQufuShandong273165China
| | - Qinghua Zhang
- College of Life SciencesQufu Normal UniversityQufuShandong273165China
| | - Peter C. Dedon
- Department of Biological Engineering and Center for Environmental Health SciencesMassachusetts Institute of TechnologyCambridgeMA02139USA
- Antimicrobial Resistance Interdisciplinary Research GroupSingapore-Massachusetts Institute of Technology Alliance for Research and Technology138602SingaporeSingapore
| | - Bo Cao
- College of Life SciencesQufu Normal UniversityQufuShandong273165China
| | - Stefanie Kellner
- Ludwig-Maximilians Universität MünchenButenandtstr. 5–1381137MünchenDeutschland
- Institute of Pharmaceutical ChemistryGoethe-University FrankfurtMax-von-Laue-Str. 960438FrankfurtGermany
| |
Collapse
|
14
|
Kanai Y, Kobayashi T. FAST Proteins: Development and Use of Reverse Genetics Systems for Reoviridae Viruses. Annu Rev Virol 2021; 8:515-536. [PMID: 34586868 DOI: 10.1146/annurev-virology-091919-070225] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Reverse genetics systems for viruses, the technology used to generate gene-engineered recombinant viruses from artificial genes, enable the study of the roles of the individual nucleotides and amino acids of viral genes and proteins in infectivity, replication, and pathogenicity. The successful development of a reverse genetics system for poliovirus in 1981 accelerated the establishment of protocols for other RNA viruses important for human health. Despite multiple efforts, rotavirus (RV), which causes severe gastroenteritis in infants, was refractory to reverse genetics analysis, and the first complete reverse genetics system for RV was established in 2017. This novel technique involves use of the fusogenic protein FAST (fusion-associated small transmembrane) derived from the bat-borne Nelson Bay orthoreovirus, which induces massive syncytium formation. Co-transfection of a FAST-expressing plasmid with complementary DNAs encoding RV genes enables rescue of recombinant RV. This review focuses on methodological insights into the reverse genetics system for RV and discusses applications and potential improvements to this system.
Collapse
Affiliation(s)
- Yuta Kanai
- Department of Virology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871, Japan; ,
| | - Takeshi Kobayashi
- Department of Virology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871, Japan; ,
| |
Collapse
|
15
|
Methyltransferase-like 3 Modulates Severe Acute Respiratory Syndrome Coronavirus-2 RNA N6-Methyladenosine Modification and Replication. mBio 2021; 12:e0106721. [PMID: 34225491 PMCID: PMC8437041 DOI: 10.1128/mbio.01067-21] [Citation(s) in RCA: 68] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The coronavirus disease 2019 pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is an ongoing global public crisis. Although viral RNA modification has been reported based on the transcriptome architecture, the types and functions of RNA modification are still unknown. In this study, we evaluated the roles of RNA N6-methyladenosine (m6A) modification in SARS-CoV-2. Our methylated RNA immunoprecipitation sequencing (MeRIP-Seq) and Nanopore direct RNA sequencing (DRS) analysis showed that SARS-CoV-2 RNA contained m6A modification. Moreover, SARS-CoV-2 infection not only increased the expression of methyltransferase-like 3 (METTL3) but also altered its distribution. Modification of METTL3 expression by short hairpin RNA or plasmid transfection for knockdown or overexpression, respectively, affected viral replication. Furthermore, the viral key protein RdRp interacted with METTL3, and METTL3 was distributed in both the nucleus and cytoplasm in the presence of RdRp. RdRp appeared to modulate the sumoylation and ubiquitination of METTL3 via an unknown mechanism. Taken together, our findings demonstrated that the host m6A modification complex interacted with viral proteins to modulate SARS-CoV-2 replication.
Collapse
|
16
|
De Paolis V, Lorefice E, Orecchini E, Carissimi C, Laudadio I, Fulci V. Epitranscriptomics: A New Layer of microRNA Regulation in Cancer. Cancers (Basel) 2021; 13:3372. [PMID: 34282776 PMCID: PMC8268402 DOI: 10.3390/cancers13133372] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 06/30/2021] [Accepted: 06/30/2021] [Indexed: 12/15/2022] Open
Abstract
MicroRNAs are pervasive regulators of gene expression at the post-transcriptional level in metazoan, playing key roles in several physiological and pathological processes. Accordingly, these small non-coding RNAs are also involved in cancer development and progression. Furthermore, miRNAs represent valuable diagnostic and prognostic biomarkers in malignancies. In the last twenty years, the role of RNA modifications in fine-tuning gene expressions at several levels has been unraveled. All RNA species may undergo post-transcriptional modifications, collectively referred to as epitranscriptomic modifications, which, in many instances, affect RNA molecule properties. miRNAs are not an exception, in this respect, and they have been shown to undergo several post-transcriptional modifications. In this review, we will summarize the recent findings concerning miRNA epitranscriptomic modifications, focusing on their potential role in cancer development and progression.
Collapse
Affiliation(s)
| | | | | | - Claudia Carissimi
- Dipartimento di Medicina Molecolare, Sapienza Università di Roma, 00161 Rome, Italy; (V.D.P.); (E.L.); (E.O.); (V.F.)
| | - Ilaria Laudadio
- Dipartimento di Medicina Molecolare, Sapienza Università di Roma, 00161 Rome, Italy; (V.D.P.); (E.L.); (E.O.); (V.F.)
| | | |
Collapse
|
17
|
Tomita T, Kato M, Mishima T, Matsunaga Y, Sanjo H, Ito KI, Minagawa K, Matsui T, Oikawa H, Takahashi S, Takao T, Iwai N, Mino T, Takeuchi O, Maru Y, Hiratsuka S. Extracellular mRNA transported to the nucleus exerts translation-independent function. Nat Commun 2021; 12:3655. [PMID: 34135341 PMCID: PMC8208975 DOI: 10.1038/s41467-021-23969-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 05/27/2021] [Indexed: 12/19/2022] Open
Abstract
RNA in extracellular vesicles (EVs) are uptaken by cells, where they regulate fundamental cellular functions. EV-derived mRNA in recipient cells can be translated. However, it is still elusive whether “naked nonvesicular extracellular mRNA” (nex-mRNA) that are not packed in EVs can be uptaken by cells and, if so, whether they have any functions in recipient cells. Here, we show the entrance of nex-mRNA in the nucleus, where they exert a translation-independent function. Human nex-interleukin-1β (IL1β)-mRNA outside cells proved to be captured by RNA-binding zinc finger CCCH domain containing protein 12D (ZC3H12D)-expressing human natural killer (NK) cells. ZC3H12D recruited to the cell membrane binds to the 3′-untranslated region of nex-IL1β-mRNA and transports it to the nucleus. The nex-IL1β-mRNA in the NK cell nucleus upregulates antiapoptotic gene expression, migration activity, and interferon-γ production, leading to the killing of cancer cells and antimetastasis in mice. These results implicate the diverse actions of mRNA. Nonvesicular extracellular RNA (nex-RNA) that are not packed in extracellular vesicles is detected outside the cell, but it is poorly understood. Here the authors report that nex-RNA is captured by a zinc finger protein and transported to the nucleus to enhance antimetastatic characters of the cell.
Collapse
Affiliation(s)
- Takeshi Tomita
- Institute for Biomedical Sciences, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, School of Medicine, Matsumoto, Nagano, Japan.,Department of Biochemistry and Molecular Biology, Shinshu University, School of Medicine, Matsumoto, Nagano, Japan
| | - Masayoshi Kato
- Institute for Biomedical Sciences, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, School of Medicine, Matsumoto, Nagano, Japan.,Department of Biochemistry and Molecular Biology, Shinshu University, School of Medicine, Matsumoto, Nagano, Japan
| | - Taishi Mishima
- Department of Pharmacology, Tokyo Women's Medical University, Shinjuku, Tokyo, Japan
| | - Yuta Matsunaga
- Department of Pharmacology, Tokyo Women's Medical University, Shinjuku, Tokyo, Japan
| | - Hideki Sanjo
- Department of Molecular and Cellular Immunology, Shinshu University, School of Medicine, Matsumoto, Nagano, Japan
| | - Ken-Ichi Ito
- Division of Breast, Endocrine and Respiratory Surgery, Department of Surgery, Shinshu University, School of Medicine, Matsumoto, Nagano, Japan
| | - Kentaro Minagawa
- Department of Hematology/Oncology, Penn State College of Medicine, Hershey, PA, USA
| | - Toshimitsu Matsui
- Department of Hematology, Nishiwaki Municipal Hospital, Nishiwaki, Hyogo, Japan
| | - Hiroyuki Oikawa
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai, Japan
| | - Satoshi Takahashi
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai, Japan
| | - Toshifumi Takao
- Institute for Protein Research, Osaka University, Suita, Osaka, Japan
| | - Noriki Iwai
- Department of Medical Chemistry, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Takashi Mino
- Department of Medical Chemistry, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Osamu Takeuchi
- Department of Medical Chemistry, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Yoshiro Maru
- Department of Pharmacology, Tokyo Women's Medical University, Shinjuku, Tokyo, Japan.
| | - Sachie Hiratsuka
- Institute for Biomedical Sciences, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, School of Medicine, Matsumoto, Nagano, Japan. .,Department of Biochemistry and Molecular Biology, Shinshu University, School of Medicine, Matsumoto, Nagano, Japan.
| |
Collapse
|
18
|
The Mammalian Cap-Specific m 6Am RNA Methyltransferase PCIF1 Regulates Transcript Levels in Mouse Tissues. Cell Rep 2021; 32:108038. [PMID: 32814042 DOI: 10.1016/j.celrep.2020.108038] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 07/10/2020] [Accepted: 07/23/2020] [Indexed: 12/15/2022] Open
Abstract
The 5' end of eukaryotic mRNAs is protected by the m7G-cap structure. The transcription start site nucleotide is ribose methylated (Nm) in many eukaryotes, whereas an adenosine at this position is further methylated at the N6 position (m6A) by the mammalian Phosphorylated C-terminal domain (CTD)-interacting Factor 1 (PCIF1) to generate m6Am. Here, we show that although the loss of cap-specific m6Am in mice does not affect viability or fertility, the Pcif1 mutants display reduced body weight. Transcriptome analyses of mutant mouse tissues support a role for the cap-specific m6Am modification in stabilizing transcripts. In contrast, the Drosophila Pcif1 is catalytically dead, but like its mammalian counterpart, it retains the ability to associate with the Ser5-phosphorylated CTD of RNA polymerase II (RNA Pol II). Finally, we show that the Trypanosoma Pcif1 is an m6Am methylase that contributes to the N6,N6,2'-O-trimethyladenosine (m62Am) in the hypermethylated cap4 structure of trypanosomatids. Thus, PCIF1 has evolved to function in catalytic and non-catalytic roles.
Collapse
|
19
|
Netzband R, Pager CT. Viral Epitranscriptomics. Virology 2021. [DOI: 10.1002/9781119818526.ch4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
20
|
Kniert J, Lin QF, Shmulevitz M. Captivating Perplexities of Spinareovirinae 5' RNA Caps. Viruses 2021; 13:v13020294. [PMID: 33668598 PMCID: PMC7918360 DOI: 10.3390/v13020294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 02/08/2021] [Accepted: 02/08/2021] [Indexed: 11/16/2022] Open
Abstract
RNAs with methylated cap structures are present throughout multiple domains of life. Given that cap structures play a myriad of important roles beyond translation, such as stability and immune recognition, it is not surprising that viruses have adopted RNA capping processes for their own benefit throughout co-evolution with their hosts. In fact, that RNAs are capped was first discovered in a member of the Spinareovirinae family, Cypovirus, before these findings were translated to other domains of life. This review revisits long-past knowledge and recent studies on RNA capping among members of Spinareovirinae to help elucidate the perplex processes of RNA capping and functions of RNA cap structures during Spinareovirinae infection. The review brings to light the many uncertainties that remain about the precise capping status, enzymes that facilitate specific steps of capping, and the functions of RNA caps during Spinareovirinae replication.
Collapse
|
21
|
The Paradoxes of Viral mRNA Translation during Mammalian Orthoreovirus Infection. Viruses 2021; 13:v13020275. [PMID: 33670092 PMCID: PMC7916891 DOI: 10.3390/v13020275] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 02/08/2021] [Accepted: 02/09/2021] [Indexed: 02/06/2023] Open
Abstract
De novo viral protein synthesis following entry into host cells is essential for viral replication. As a consequence, viruses have evolved mechanisms to engage the host translational machinery while at the same time avoiding or counteracting host defenses that act to repress translation. Mammalian orthoreoviruses are dsRNA-containing viruses whose mRNAs were used as models for early investigations into the mechanisms that underpin the recognition and engagement of eukaryotic mRNAs by host cell ribosomes. However, there remain many unanswered questions and paradoxes regarding translation of reoviral mRNAs in the context of infection. This review summarizes the current state of knowledge about reovirus translation, identifies key unanswered questions, and proposes possible pathways toward a better understanding of reovirus translation.
Collapse
|
22
|
Kanai Y, Kobayashi T. Rotavirus reverse genetics systems: Development and application. Virus Res 2021; 295:198296. [PMID: 33440223 DOI: 10.1016/j.virusres.2021.198296] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 12/31/2020] [Accepted: 01/05/2021] [Indexed: 12/14/2022]
Abstract
Rotaviruses (RVs) cause acute gastroenteritis in infants and young children. Since 2006, live-attenuated vaccines have reduced the number of RV-associated deaths; however, RV is still responsible for an estimated 228,047 annual deaths worldwide. RV, a member of the family Reoviridae, has an 11-segmented double-stranded RNA genome contained within a non-enveloped, triple layered virus particle. In 2017, a long-awaited helper virus-free reverse genetics system for RV was established. Since then, numerous studies have reported the generation of recombinant RVs; these studies verify the robustness of reverse genetics systems. This review provides technical insight into current reverse genetics systems for RVs, as well as discussing basic and applied studies that have used these systems.
Collapse
Affiliation(s)
- Yuta Kanai
- Department of Virology, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita, Osaka, 565-0871, Japan.
| | - Takeshi Kobayashi
- Department of Virology, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita, Osaka, 565-0871, Japan.
| |
Collapse
|
23
|
Moss B. Investigating Viruses During the Transformation of Molecular Biology: Part II. Annu Rev Virol 2020; 7:15-36. [PMID: 32392458 DOI: 10.1146/annurev-virology-021020-100558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
My scientific career started at an extraordinary time, shortly after the discoveries of the helical structure of DNA, the central dogma of DNA to RNA to protein, and the genetic code. Part I of this series emphasizes my education and early studies highlighted by the isolation and characterization of numerous vaccinia virus enzymes, determination of the cap structure of messenger RNA, and development of poxviruses as gene expression vectors for use as recombinant vaccines. Here I describe a shift in my research focus to combine molecular biology and genetics for a comprehensive understanding of poxvirus biology. The dominant paradigm during the early years was to select a function, isolate the responsible proteins, and locate the corresponding gene, whereas later the common paradigm was to select a gene, make a mutation, and determine the altered function. Motivations, behind-the-scenes insights, importance of new technologies, and the vital roles of trainees and coworkers are emphasized.
Collapse
Affiliation(s)
- Bernard Moss
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA;
| |
Collapse
|
24
|
Sikorski PJ, Warminski M, Kubacka D, Ratajczak T, Nowis D, Kowalska J, Jemielity J. The identity and methylation status of the first transcribed nucleotide in eukaryotic mRNA 5' cap modulates protein expression in living cells. Nucleic Acids Res 2020; 48:1607-1626. [PMID: 31984425 PMCID: PMC7038993 DOI: 10.1093/nar/gkaa032] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 01/08/2020] [Accepted: 01/13/2020] [Indexed: 12/21/2022] Open
Abstract
7-Methylguanosine 5' cap on mRNA is necessary for efficient protein expression in vitro and in vivo. Recent studies revealed structural diversity of endogenous mRNA caps, which carry different 5'-terminal nucleotides and additional methylations (2'-O-methylation and m6A). Currently available 5'-capping methods do not address this diversity. We report trinucleotide 5' cap analogs (m7GpppN(m)pG), which are utilized by RNA polymerase T7 to initiate transcription from templates carrying Φ6.5 promoter and enable production of mRNAs differing in the identity of the first transcribed nucleotide (N = A, m6A, G, C, U) and its methylation status (±2'-O-methylation). HPLC-purified mRNAs carrying these 5' caps were used to study protein expression in three mammalian cell lines (3T3-L1, HeLa and JAWS II). The highest expression was observed for mRNAs carrying 5'-terminal A/Am and m6Am, whereas the lowest was observed for G and Gm. The mRNAs carrying 2'-O-methyl at the first transcribed nucleotide (cap 1) had significantly higher expression than unmethylated counterparts (cap 0) only in JAWS II dendritic cells. Further experiments indicated that the mRNA expression characteristic does not correlate with affinity for translation initiation factor 4E or in vitro susceptibility to decapping, but instead depends on mRNA purity and the immune state of the cells.
Collapse
Affiliation(s)
- Pawel J Sikorski
- Centre of New Technologies, University of Warsaw, Banacha 2C, 02-097 Warsaw, Poland
| | - Marcin Warminski
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
| | - Dorota Kubacka
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
| | - Tomasz Ratajczak
- Centre of New Technologies, University of Warsaw, Banacha 2C, 02-097 Warsaw, Poland
| | - Dominika Nowis
- Centre of New Technologies, University of Warsaw, Banacha 2C, 02-097 Warsaw, Poland
- Department of Genomic Medicine, Medical University of Warsaw, Nielubowicza 5, 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
| |
Collapse
|
25
|
Netzband R, Pager CT. Epitranscriptomic marks: Emerging modulators of RNA virus gene expression. WILEY INTERDISCIPLINARY REVIEWS-RNA 2019; 11:e1576. [PMID: 31694072 PMCID: PMC7169815 DOI: 10.1002/wrna.1576] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 10/07/2019] [Accepted: 10/08/2019] [Indexed: 12/27/2022]
Abstract
Epitranscriptomics, the study of posttranscriptional chemical moieties placed on RNA, has blossomed in recent years. This is due in part to the emergence of high‐throughput detection methods as well as the burst of discoveries showing biological function of select chemical marks. RNA modifications have been shown to affect RNA structure, localization, and functions such as alternative splicing, stabilizing transcripts, nuclear export, cap‐dependent and cap‐independent translation, microRNA biogenesis and binding, RNA degradation, and immune regulation. As such, the deposition of chemical marks on RNA has the unique capability to spatially and temporally regulate gene expression. The goal of this article is to present the exciting convergence of the epitranscriptomic and virology fields, specifically the deposition and biological impact of N7‐methylguanosine, ribose 2′‐O‐methylation, pseudouridine, inosine, N6‐methyladenosine, and 5‐methylcytosine epitranscriptomic marks on gene expression of RNA viruses. This article is categorized under:RNA in Disease and Development > RNA in Disease RNA Interactions with Proteins and Other Molecules > Protein–RNA Interactions: Functional Implications
Collapse
Affiliation(s)
- Rachel Netzband
- Department of Biological Sciences, The RNA Institute, University at Albany-SUNY, Albany, New York
| | - Cara T Pager
- Department of Biological Sciences, The RNA Institute, University at Albany-SUNY, Albany, New York
| |
Collapse
|
26
|
Tahmasebi S, Sonenberg N, Hershey JWB, Mathews MB. Protein Synthesis and Translational Control: A Historical Perspective. Cold Spring Harb Perspect Biol 2019; 11:cshperspect.a035584. [PMID: 30082466 DOI: 10.1101/cshperspect.a035584] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Protein synthesis and its regulation are central to all known forms of life and impinge on biological arenas as varied as agriculture, biotechnology, and medicine. Otherwise known as translation and translational control, these processes have been investigated with increasing intensity since the middle of the 20th century, and in increasing depth with advances in molecular and cell biology. We review the origins of the field, focusing on the underlying concepts and early studies of the cellular machinery and mechanisms involved. We highlight key discoveries and events on a timeline, consider areas where current research has engendered new ideas, and conclude with some speculation on future directions for the field.
Collapse
Affiliation(s)
- Soroush Tahmasebi
- Department of Biochemistry and Goodman Cancer Research Center, McGill University, Montreal, QC H3A 1A3, Canada
| | - Nahum Sonenberg
- Department of Biochemistry and Goodman Cancer Research Center, McGill University, Montreal, QC H3A 1A3, Canada
| | - John W B Hershey
- Department of Biochemistry and Molecular Medicine, University of California, School of Medicine, Davis, California 95616
| | - Michael B Mathews
- Department of Medicine, Rutgers New Jersey Medical School, Newark, New Jersey 07103
| |
Collapse
|
27
|
Li Y, Wu K, Quan W, Yu L, Chen S, Cheng C, Wu Q, Zhao S, Zhang Y, Zhou L. The dynamics of FTO binding and demethylation from the m 6A motifs. RNA Biol 2019; 16:1179-1189. [PMID: 31149892 PMCID: PMC6693534 DOI: 10.1080/15476286.2019.1621120] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 04/20/2019] [Accepted: 05/09/2019] [Indexed: 10/26/2022] Open
Abstract
N6-methyladenosine (m6A) is considered as a reversible RNA modification occurring more frequently on the GAC than AAC context in vivo, which regulates post-transcriptional gene expression in mammalian cells. m6A 'writers' METTL3 and METTL14 demonstrate a strong preference for binding AC-containing motifs in living cells. However, this evidence is currently lacking for m6A erasers, leaving the dynamics of the internal m6A modification under debate recently. We analysed three recently published FTO CLIP-seq data sets and two generated in this study, one of the two known m6A 'erasers'. FTO binding peaks from all cell lines contain RRACH motifs. Only those from K562, 3T3-L1and HeLa cells were enriched in AC-containing motifs, while those from HEK293 were not. The exogenously overexpressed FTO effectively binds to m6A motif-containing RNA sites. FTO overexpression specifically removed m6A modification from GGACU and RRACU motifs in a concentration-dependent manner. These findings underline the dynamics of FTO in target selection, which is predicted to contribute to both the m6A dynamics and the FTO plasticity in biological functions and diseases.
Collapse
Affiliation(s)
- Yixing Li
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Animal Science and Technology, Guangxi University, Nanning, P.R. China
| | - Kejing Wu
- Center for Genome Analysis, ABLife Inc., Wuhan, Hubei, China
| | - Weili Quan
- Center for Genome Analysis, ABLife Inc., Wuhan, Hubei, China
- Laboratory for Genome Regulation and Human Health, ABLife Inc., Wuhan, Hubei, China
| | - Lin Yu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Animal Science and Technology, Guangxi University, Nanning, P.R. China
| | - Shuang Chen
- Laboratory for Genome Regulation and Human Health, ABLife Inc., Wuhan, Hubei, China
| | - Chao Cheng
- Center for Genome Analysis, ABLife Inc., Wuhan, Hubei, China
| | - Qijia Wu
- Laboratory for Genome Regulation and Human Health, ABLife Inc., Wuhan, Hubei, China
| | - Shuhong Zhao
- Key Lab of Agricultural Animal Genetics and Breeding, Ministry of Education, College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan, P. R. China
| | - Yi Zhang
- Center for Genome Analysis, ABLife Inc., Wuhan, Hubei, China
- Laboratory for Genome Regulation and Human Health, ABLife Inc., Wuhan, Hubei, China
| | - Lei Zhou
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Animal Science and Technology, Guangxi University, Nanning, P.R. China
| |
Collapse
|
28
|
Wang Q, Zhang D, Guan Z, Li D, Pei K, Liu J, Zou T, Yin P. DapF stabilizes the substrate-favoring conformation of RppH to stimulate its RNA-pyrophosphohydrolase activity in Escherichia coli. Nucleic Acids Res 2019; 46:6880-6892. [PMID: 29931175 PMCID: PMC6061791 DOI: 10.1093/nar/gky528] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Accepted: 05/28/2018] [Indexed: 11/30/2022] Open
Abstract
mRNA decay is an important strategy by which bacteria can rapidly adapt to their ever-changing surroundings. The 5′-terminus state of mRNA determines the velocity of decay of many types of RNA. In Escherichia coli, RNA pyrophosphohydrolase (RppH) is responsible for the removal of the 5′-terminal triphosphate from hundreds of mRNAs and triggers its rapid degradation by ribonucleases. A diaminopimelate epimerase, DapF, can directly interact with RppH and stimulate its hydrolysis activity in vivo and in vitro. However, the molecular mechanism remains to be elucidated. Here, we determined the complex structure of DapF–RppH as a heterotetramer in a 2:2 molar ratio. DapF-bound RppH exhibits an RNA-favorable conformation similar to the RNA-bound state, suggesting that association with DapF promotes and stabilizes RppH in a conformation that facilitates substrate RNA binding and thus stimulates the activity of RppH. To our knowledge, this is the first published structure of an RNA–pyrophosphohydrolysis complex in bacteria. Our study provides a framework for further investigation of the potential regulators involved in the RNA–pyrophosphohydrolysis process in prokaryotes.
Collapse
Affiliation(s)
- Qiang Wang
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan 430070, China
| | - Delin Zhang
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan 430070, China
| | - Zeyuan Guan
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan 430070, China
| | - Dongqin Li
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan 430070, China
| | - Kai Pei
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan 430070, China
| | - Jian Liu
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan 430070, China
| | - Tingting Zou
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan 430070, China
| | - Ping Yin
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan 430070, China
| |
Collapse
|
29
|
Ogino T, Green TJ. RNA Synthesis and Capping by Non-segmented Negative Strand RNA Viral Polymerases: Lessons From a Prototypic Virus. Front Microbiol 2019; 10:1490. [PMID: 31354644 PMCID: PMC6636387 DOI: 10.3389/fmicb.2019.01490] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 06/14/2019] [Indexed: 12/26/2022] Open
Abstract
Non-segmented negative strand (NNS) RNA viruses belonging to the order Mononegavirales are highly diversified eukaryotic viruses including significant human pathogens, such as rabies, measles, Nipah, and Ebola. Elucidation of their unique strategies to replicate in eukaryotic cells is crucial to aid in developing anti-NNS RNA viral agents. Over the past 40 years, vesicular stomatitis virus (VSV), closely related to rabies virus, has served as a paradigm to study the fundamental molecular mechanisms of transcription and replication of NNS RNA viruses. These studies provided insights into how NNS RNA viruses synthesize 5'-capped mRNAs using their RNA-dependent RNA polymerase L proteins equipped with an unconventional mRNA capping enzyme, namely GDP polyribonucleotidyltransferase (PRNTase), domain. PRNTase or PRNTase-like domains are evolutionally conserved among L proteins of all known NNS RNA viruses and their related viruses belonging to Jingchuvirales, a newly established order, in the class Monjiviricetes, suggesting that they may have evolved from a common ancestor that acquired the unique capping system to replicate in a primitive eukaryotic host. This article reviews what has been learned from biochemical and structural studies on the VSV RNA biosynthesis machinery, and then focuses on recent advances in our understanding of regulatory and catalytic roles of the PRNTase domain in RNA synthesis and capping.
Collapse
Affiliation(s)
- Tomoaki Ogino
- Department of Molecular Biology and Microbiology, Case Western Reserve University School of Medicine, Cleveland, OH, United States
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, United States
| | - Todd J. Green
- Department of Microbiology, School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| |
Collapse
|
30
|
Trotman JB, Schoenberg *DR. A recap of RNA recapping. WILEY INTERDISCIPLINARY REVIEWS. RNA 2019; 10:e1504. [PMID: 30252202 PMCID: PMC6294674 DOI: 10.1002/wrna.1504] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 07/13/2018] [Accepted: 08/01/2018] [Indexed: 12/12/2022]
Abstract
The N7-methylguanosine cap is a hallmark of the 5' end of eukaryotic mRNAs and is required for gene expression. Loss of the cap was believed to lead irreversibly to decay. However, nearly a decade ago, it was discovered that mammalian cells contain enzymes in the cytoplasm that are capable of restoring caps onto uncapped RNAs. In this review, we summarize recent advances in our understanding of cytoplasmic RNA recapping and discuss the biochemistry of this process and its impact on regulating and diversifying the transcriptome. Although most studies focus on mammalian RNA recapping, we also highlight new observations for recapping in disparate eukaryotic organisms, with the trypanosome recapping system appearing to be a fascinating example of convergent evolution. We conclude with emerging insights into the biological significance of RNA recapping and prospects for the future of this evolving area of study. This article is categorized under: RNA Processing > RNA Editing and Modification Translation > Translation Regulation RNA Processing > Capping and 5' End Modifications RNA Turnover and Surveillance > Regulation of RNA Stability.
Collapse
Affiliation(s)
- Jackson B. Trotman
- Department of Biological Chemistry and Pharmacology, Center for RNA Biology, The Ohio State University, Columbus, OH 43210,
| | - *Daniel R. Schoenberg
- Department of Biological Chemistry and Pharmacology, Center for RNA Biology, The Ohio State University, Columbus, OH 43210, schoenberg,
| |
Collapse
|
31
|
Tan B, Gao SJ. RNA epitranscriptomics: Regulation of infection of RNA and DNA viruses by N 6 -methyladenosine (m 6 A). Rev Med Virol 2018; 28:e1983. [PMID: 29698584 PMCID: PMC6339815 DOI: 10.1002/rmv.1983] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 03/24/2018] [Accepted: 03/29/2018] [Indexed: 02/05/2023]
Abstract
N6 -methyladenosine (m6 A) was discovered 4 decades ago. However, the functions of m6 A and the cellular machinery that regulates its changes have just been revealed in the last few years. m6 A is an abundant internal mRNA modification on cellular RNA and is implicated in diverse cellular functions. Recent works have demonstrated the presence of m6 A in the genomes of RNA viruses and transcripts of a DNA virus with either a proviral or antiviral role. Here, we first summarize what is known about the m6 A "writers," "erasers," "readers," and "antireaders" as well as the role of m6 A in mRNA metabolism. We then review how the replications of numerous viruses are enhanced and restricted by m6 A with emphasis on the oncogenic DNA virus, Kaposi sarcoma-associated herpesvirus (KSHV), whose m6 A epitranscriptome was recently mapped. In the context of KSHV, m6 A and the reader protein YTHDF2 acts as an antiviral mechanism during viral lytic replication. During viral latency, KSHV alters m6 A on genes that are implicated in cellular transformation and viral latency. Lastly, we discuss future studies that are important to further delineate the functions of m6 A in KSHV latent and lytic replication and KSHV-induced oncogenesis.
Collapse
Affiliation(s)
- Brandon Tan
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Shou-Jiang Gao
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
- Laboratory of Human Virology and Oncology, Shantou University Medical College, Shantou, Guangdong, People's Republic of China
- Department of Microbiology, Nanjing Medical University, Nanjing, Jiangsu, People's Republic of China
| |
Collapse
|
32
|
Beta RAA, Balatsos NAA. Tales around the clock: Poly(A) tails in circadian gene expression. WILEY INTERDISCIPLINARY REVIEWS-RNA 2018; 9:e1484. [PMID: 29911349 DOI: 10.1002/wrna.1484] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 04/15/2018] [Accepted: 04/20/2018] [Indexed: 11/07/2022]
Abstract
Circadian rhythms are ubiquitous time-keeping processes in eukaryotes with a period of ~24 hr. Light is perhaps the main environmental cue (zeitgeber) that affects several aspects of physiology and behaviour, such as sleep/wake cycles, orientation of birds and bees, and leaf movements in plants. Temperature can serve as the main zeitgeber in the absence of light cycles, even though it does not lead to rhythmicity through the same mechanism as light. Additional cues include feeding patterns, humidity, and social rhythms. At the molecular level, a master oscillator orchestrates circadian rhythms and organizes molecular clocks located in most cells. The generation of the 24 hr molecular clock is based on transcriptional regulation, as it drives intrinsic rhythmic changes based on interlocked transcription/translation feedback loops that synchronize expression of genes. Thus, processes and factors that determine rhythmic gene expression are important to understand circadian rhythms. Among these, the poly(A) tails of RNAs play key roles in their stability, translational efficiency and degradation. In this article, we summarize current knowledge and discuss perspectives on the role and significance of poly(A) tails and associating factors in the context of the circadian clock. This article is categorized under: RNA Turnover and Surveillance > Regulation of RNA Stability RNA Processing > 3' End Processing.
Collapse
Affiliation(s)
- Rafailia A A Beta
- Department of Biochemistry and Biotechnology, University of Thessaly, Larissa, Greece
| | - Nikolaos A A Balatsos
- Department of Biochemistry and Biotechnology, University of Thessaly, Larissa, Greece
| |
Collapse
|
33
|
Kiledjian M. Eukaryotic RNA 5'-End NAD + Capping and DeNADding. Trends Cell Biol 2018; 28:454-464. [PMID: 29544676 PMCID: PMC5962413 DOI: 10.1016/j.tcb.2018.02.005] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Revised: 01/30/2018] [Accepted: 02/15/2018] [Indexed: 12/28/2022]
Abstract
A hallmark of eukaryotic mRNAs has long been the 5'-end m7G cap. This paradigm was recently amended by recent reports that Saccharomyces cerevisiae and mammalian cells also contain mRNAs carrying a novel nicotinamide adenine dinucleotide (NAD+) cap at their 5'-end. The presence of an NAD+ cap on mRNA uncovers a previously unknown mechanism for controlling gene expression through nucleotide metabolite-directed mRNA turnover. In contrast to the m7G cap that stabilizes mRNA, the NAD+ cap targets RNA for rapid decay in mammalian cells through the DXO non-canonical decapping enzyme which removes intact NAD+ from RNA in a process termed 'deNADding'. This review highlights the identification of NAD+ caps, their mode of addition, and their functional significance in cells.
Collapse
Affiliation(s)
- Megerditch Kiledjian
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ 08854, USA.
| |
Collapse
|
34
|
Darnell RB, Ke S, Darnell JE. Pre-mRNA processing includes N6 methylation of adenosine residues that are retained in mRNA exons and the fallacy of "RNA epigenetics". RNA (NEW YORK, N.Y.) 2018; 24:262-267. [PMID: 29222117 PMCID: PMC5824346 DOI: 10.1261/rna.065219.117] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
By using a cell fraction technique that separates chromatin-associated nascent RNA, newly completed nucleoplasmic mRNA and cytoplasmic mRNA, we have shown in a previous study that residues in exons are methylated (m6A) in nascent pre-mRNA and remain methylated in the same exonic residues in nucleoplasmic and cytoplasmic mRNA. Thus, there is no evidence of a substantial degree of demethylation in mRNA exons that would correspond to so-called "epigenetic" demethylation. The turnover rate of mRNA molecules is faster, depending on m6A content in HeLa cell mRNA, suggesting that specification of mRNA stability may be the major role of m6A exon modification. In mouse embryonic stem cells (mESCs) lacking Mettl3, the major mRNA methylase, the cells continue to grow, making the same mRNAs with unchanged splicing profiles in the absence (>90%) of m6A in mRNA, suggesting no common obligatory role of m6A in splicing. All these data argue strongly against a commonly used "reversible dynamic methylation/demethylation" of mRNA, calling into question the concept of "RNA epigenetics" that parallels the well-established role of dynamic DNA epigenetics.
Collapse
Affiliation(s)
- Robert B Darnell
- Laboratory of Molecular Neuro-Oncology, The Rockefeller University, New York, New York 10065, USA
| | - Shengdong Ke
- Laboratory of Molecular Neuro-Oncology, The Rockefeller University, New York, New York 10065, USA
| | - James E Darnell
- Laboratory of Molecular Cell Biology, The Rockefeller University, New York, New York 10065, USA
| |
Collapse
|
35
|
Profile of Michael N. Hall, 2017 Albert Lasker Basic Medical Research Awardee: Target of rapamycin, cell growth, and translational control. Proc Natl Acad Sci U S A 2017; 114:11564-11567. [PMID: 29078415 DOI: 10.1073/pnas.1716203114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
|
36
|
Ke S, Pandya-Jones A, Saito Y, Fak JJ, Vågbø CB, Geula S, Hanna JH, Black DL, Darnell JE, Darnell RB. m 6A mRNA modifications are deposited in nascent pre-mRNA and are not required for splicing but do specify cytoplasmic turnover. Genes Dev 2017. [PMID: 28637692 PMCID: PMC5495127 DOI: 10.1101/gad.301036.117] [Citation(s) in RCA: 426] [Impact Index Per Article: 53.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Understanding the biologic role of N6-methyladenosine (m6A) RNA modifications in mRNA requires an understanding of when and where in the life of a pre-mRNA transcript the modifications are made. We found that HeLa cell chromatin-associated nascent pre-mRNA (CA-RNA) contains many unspliced introns and m6A in exons but very rarely in introns. The m6A methylation is essentially completed upon the release of mRNA into the nucleoplasm. Furthermore, the content and location of each m6A modification in steady-state cytoplasmic mRNA are largely indistinguishable from those in the newly synthesized CA-RNA or nucleoplasmic mRNA. This result suggests that quantitatively little methylation or demethylation occurs in cytoplasmic mRNA. In addition, only ∼10% of m6As in CA-RNA are within 50 nucleotides of 5' or 3' splice sites, and the vast majority of exons harboring m6A in wild-type mouse stem cells is spliced the same in cells lacking the major m6A methyltransferase Mettl3. Both HeLa and mouse embryonic stem cell mRNAs harboring m6As have shorter half-lives, and thousands of these mRNAs have increased half-lives (twofold or more) in Mettl3 knockout cells compared with wild type. In summary, m6A is added to exons before or soon after exon definition in nascent pre-mRNA, and while m6A is not required for most splicing, its addition in the nascent transcript is a determinant of cytoplasmic mRNA stability.
Collapse
Affiliation(s)
- Shengdong Ke
- Laboratory of Molecular Neuro-Oncology, The Rockefeller University, New York, New York 10065, USA.,Howard Hughes Medical Institute, The Rockefeller University, New York, New York 10065, USA
| | - Amy Pandya-Jones
- Department of Microbiology, Immunology, and Molecular Genetics, University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Yuhki Saito
- Laboratory of Molecular Neuro-Oncology, The Rockefeller University, New York, New York 10065, USA.,Howard Hughes Medical Institute, The Rockefeller University, New York, New York 10065, USA
| | - John J Fak
- Laboratory of Molecular Neuro-Oncology, The Rockefeller University, New York, New York 10065, USA.,Howard Hughes Medical Institute, The Rockefeller University, New York, New York 10065, USA
| | - Cathrine Broberg Vågbø
- Proteomics and Metabolomics Core Facility, Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, 7489 Trondheim, Norway
| | - Shay Geula
- The Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Jacob H Hanna
- The Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Douglas L Black
- Department of Microbiology, Immunology, and Molecular Genetics, University of California at Los Angeles, Los Angeles, California 90095, USA
| | - James E Darnell
- Laboratory of Molecular Cell Biology, The Rockefeller University, New York, New York 10065, USA
| | - Robert B Darnell
- Laboratory of Molecular Neuro-Oncology, The Rockefeller University, New York, New York 10065, USA.,Howard Hughes Medical Institute, The Rockefeller University, New York, New York 10065, USA
| |
Collapse
|
37
|
Profile of Nahum Sonenberg. Proc Natl Acad Sci U S A 2017; 114:8905-8907. [DOI: 10.1073/pnas.1711714114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
|
38
|
Abstract
This Reflections article describes my early work on viral enzymes and the discovery of mRNA capping, how my training in medicine and biochemistry merged as I evolved into a virologist, the development of viruses as vaccine vectors, and how scientific and technological developments during the 1970s and beyond set the stage for the interrogation of nearly every step in the reproductive cycle of vaccinia virus (VACV), a large DNA virus with about 200 genes. The reader may view this article as a work in progress, because I remain actively engaged in research at the National Institutes of Health (NIH) notwithstanding 50 memorable years there.
Collapse
Affiliation(s)
- Bernard Moss
- From the Laboratory of Viral Diseases, NIAID, National Institutes of Health, Bethesda, Maryland 20892
| |
Collapse
|
39
|
Kanai Y, Kobayashi T. [A plasmid-based reverse genetics system for rotaviruses]. Uirusu 2017; 67:99-110. [PMID: 30369541 DOI: 10.2222/jsv.67.99] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Rotavirus (RV), a non-enveloped icosahedral virus containing eleven gene segments of double-stranded RNA, is the leading cause of severe, acute diarrhea among infants and young children worldwide. Safe and effective rotavirus vaccines have been available since 2006, and have markedly reduced the number of deaths by severe gastroenteritis. However, rotaviruses are still responsible for approximately 200,000 deaths annually worldwide. Reverse genetics systems for the manipulation of viral genomes are a powerful approach for studying viral replication and pathogenesis, and for developing vaccines and viral vectors. The understanding of the molecular mechanisms underlying RV pathogenesis, or development of next generation vaccines, has been hampered by the lack of a complete reverse genetics system. Recently, we developed a novel reverse genetics system which enabled recovery of recombinant RVs entirely from cloned cDNAs. This new strategy requires co-expression of a small transmembrane protein that accelerates cell-to-cell fusion and vaccinia virus capping enzyme. In this review, the strategies and history of the development of reverse genetics systems for the family Reoviridae are described.
Collapse
Affiliation(s)
- Yuta Kanai
- Department of Virology, Research Institute for Microbial Diseases, Osaka University
| | - Takeshi Kobayashi
- Department of Virology, Research Institute for Microbial Diseases, Osaka University
| |
Collapse
|
40
|
Fry M. Dissolution of hypotheses in biochemistry: three case studies. HISTORY AND PHILOSOPHY OF THE LIFE SCIENCES 2016; 38:17. [PMID: 27813029 DOI: 10.1007/s40656-016-0118-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 10/26/2016] [Indexed: 06/06/2023]
Abstract
The history of biochemistry and molecular biology is replete with examples of erroneous theories that persisted for considerable lengths of time before they were rejected. This paper examines patterns of dissolution of three such erroneous hypotheses: The idea that nucleic acids are tetrads of the four nucleobases ('the tetranucleotide hypothesis'); the notion that proteins are collinear with their encoding genes in all branches of life; and the hypothesis that proteins are synthesized by reverse action of proteolytic enzymes. Analysis of these cases indicates that amassed contradictory empirical findings did not prompt critical experimental testing of the prevailing theories nor did they elicit alternative hypotheses. Rather, the incorrect models collapsed when experiments that were not purposely designed to test their validity exposed new facts.
Collapse
Affiliation(s)
- Michael Fry
- Department of Biochemistry, Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, POB 9649, 31096, Haifa, Israel.
| |
Collapse
|
41
|
[The multifunctional RNA polymerase L protein of non-segmented negative strand RNA viruses catalyzes unique mRNA capping]. Uirusu 2016; 64:165-78. [PMID: 26437839 DOI: 10.2222/jsv.64.165] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Non-segmented negative strand RNA viruses belonging to the Mononegavirales order possess RNA-dependent RNA polymerase L proteins within viral particles. The L protein is a multifunctional enzyme catalyzing viral RNA synthesis and processing (i.e., mRNA capping, cap methylation, and polyadenylation). Using vesicular stomatitis virus (VSV) as a prototypic model virus, we have shown that the L protein catalyzes the unconventional mRNA capping reaction, which is strikingly different from the eukaryotic reaction. Furthermore, co-transcriptional pre-mRNA capping with the VSV L protein was found to be required for accurate stop?start transcription to synthesize full-length mRNAs in vitro and virus propagation in host cells. This article provides a review of historical and present studies leading to the elucidation of the molecular mechanism of VSV mRNA capping.
Collapse
|
42
|
The molecular choreography of protein synthesis: translational control, regulation, and pathways. Q Rev Biophys 2016; 49:e11. [PMID: 27658712 DOI: 10.1017/s0033583516000056] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Translation of proteins by the ribosome regulates gene expression, with recent results underscoring the importance of translational control. Misregulation of translation underlies many diseases, including cancer and many genetic diseases. Decades of biochemical and structural studies have delineated many of the mechanistic details in prokaryotic translation, and sketched the outlines of eukaryotic translation. However, translation may not proceed linearly through a single mechanistic pathway, but likely involves multiple pathways and branchpoints. The stochastic nature of biological processes would allow different pathways to occur during translation that are biased by the interaction of the ribosome with other translation factors, with many of the steps kinetically controlled. These multiple pathways and branchpoints are potential regulatory nexus, allowing gene expression to be tuned at the translational level. As research focus shifts toward eukaryotic translation, certain themes will be echoed from studies on prokaryotic translation. This review provides a general overview of the dynamic data related to prokaryotic and eukaryotic translation, in particular recent findings with single-molecule methods, complemented by biochemical, kinetic, and structural findings. We will underscore the importance of viewing the process through the viewpoints of regulation, translational control, and heterogeneous pathways.
Collapse
|
43
|
Ke S, Alemu EA, Mertens C, Gantman EC, Fak JJ, Mele A, Haripal B, Zucker-Scharff I, Moore MJ, Park CY, Vågbø CB, Kusśnierczyk A, Klungland A, Darnell JE, Darnell RB. A majority of m6A residues are in the last exons, allowing the potential for 3' UTR regulation. Genes Dev 2015; 29:2037-53. [PMID: 26404942 PMCID: PMC4604345 DOI: 10.1101/gad.269415.115] [Citation(s) in RCA: 633] [Impact Index Per Article: 63.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 09/01/2015] [Indexed: 12/13/2022]
Abstract
Ke et al. found that >70% of m6A residues are present in the 3′-most (last) exons, with a sharp rise within 150–400 nucleotides of the start of the last exon. This report also suggests a role of m6A modification in regulating proximal alternative polyA choice. We adapted UV CLIP (cross-linking immunoprecipitation) to accurately locate tens of thousands of m6A residues in mammalian mRNA with single-nucleotide resolution. More than 70% of these residues are present in the 3′-most (last) exons, with a very sharp rise (sixfold) within 150–400 nucleotides of the start of the last exon. Two-thirds of last exon m6A and >40% of all m6A in mRNA are present in 3′ untranslated regions (UTRs); contrary to earlier suggestions, there is no preference for location of m6A sites around stop codons. Moreover, m6A is significantly higher in noncoding last exons than in next-to-last exons harboring stop codons. We found that m6A density peaks early in the 3′ UTR and that, among transcripts with alternative polyA (APA) usage in both the brain and the liver, brain transcripts preferentially use distal polyA sites, as reported, and also show higher proximal m6A density in the last exons. Furthermore, when we reduced m6A methylation by knocking down components of the methylase complex and then examined 661 transcripts with proximal m6A peaks in last exons, we identified a set of 111 transcripts with altered (approximately two-thirds increased proximal) APA use. Taken together, these observations suggest a role of m6A modification in regulating proximal alternative polyA choice.
Collapse
Affiliation(s)
- Shengdong Ke
- Laboratory of Molecular Neuro-Oncology, The Rockefeller University, New York, New York 10065, USA; Howard Hughes Medical Institute, The Rockefeller University, New York, New York 10065, USA
| | - Endalkachew A Alemu
- Department of Microbiology, Division of Diagnostics and Intervention, Institute of Clinical Medicine, Oslo University Hospital, Rikshospitalet, NO-0027, Oslo, Norway; Department of Molecular Medicine, Faculty of Medicine, Institute of Basic Medical Sciences, University of Oslo, 0316 Oslo, Norway
| | - Claudia Mertens
- Laboratory of Molecular Cell Biology, The Rockefeller University, New York, New York 10065, USA
| | - Emily Conn Gantman
- Laboratory of Molecular Neuro-Oncology, The Rockefeller University, New York, New York 10065, USA; New York Genome Center, New York, New York 10013, USA
| | - John J Fak
- Laboratory of Molecular Neuro-Oncology, The Rockefeller University, New York, New York 10065, USA; Howard Hughes Medical Institute, The Rockefeller University, New York, New York 10065, USA
| | - Aldo Mele
- Laboratory of Molecular Neuro-Oncology, The Rockefeller University, New York, New York 10065, USA; Howard Hughes Medical Institute, The Rockefeller University, New York, New York 10065, USA
| | - Bhagwattie Haripal
- Laboratory of Molecular Cell Biology, The Rockefeller University, New York, New York 10065, USA
| | - Ilana Zucker-Scharff
- Laboratory of Molecular Neuro-Oncology, The Rockefeller University, New York, New York 10065, USA; Howard Hughes Medical Institute, The Rockefeller University, New York, New York 10065, USA
| | - Michael J Moore
- Laboratory of Molecular Neuro-Oncology, The Rockefeller University, New York, New York 10065, USA; Howard Hughes Medical Institute, The Rockefeller University, New York, New York 10065, USA
| | - Christopher Y Park
- Laboratory of Molecular Neuro-Oncology, The Rockefeller University, New York, New York 10065, USA; New York Genome Center, New York, New York 10013, USA
| | - Cathrine Broberg Vågbø
- Proteomics and Metabolomics Core Facility, Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, 7489 Trondheim, Norway
| | - Anna Kusśnierczyk
- Proteomics and Metabolomics Core Facility, Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, 7489 Trondheim, Norway
| | - Arne Klungland
- Department of Microbiology, Division of Diagnostics and Intervention, Institute of Clinical Medicine, Oslo University Hospital, Rikshospitalet, NO-0027, Oslo, Norway; Department of Molecular Medicine, Faculty of Medicine, Institute of Basic Medical Sciences, University of Oslo, 0316 Oslo, Norway
| | - James E Darnell
- Laboratory of Molecular Cell Biology, The Rockefeller University, New York, New York 10065, USA
| | - Robert B Darnell
- Laboratory of Molecular Neuro-Oncology, The Rockefeller University, New York, New York 10065, USA; Howard Hughes Medical Institute, The Rockefeller University, New York, New York 10065, USA; New York Genome Center, New York, New York 10013, USA
| |
Collapse
|
44
|
FURUICHI Y. Discovery of m(7)G-cap in eukaryotic mRNAs. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2015; 91:394-409. [PMID: 26460318 PMCID: PMC4729855 DOI: 10.2183/pjab.91.394] [Citation(s) in RCA: 162] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Terminal structure analysis of an insect cytoplasmic polyhedrosis virus (CPV) genome RNA in the early 1970s at the National Institute of Genetics in Japan yielded a 2'-O-methylated nucleotide in the 5' end of double-stranded RNA genome. This finding prompted me to add S-adenosyl-L-methionine, a natural methylation donor, to the in vitro transcription reaction of viruses that contain RNA polymerase. This effort resulted in unprecedented mRNA synthesis that generates a unique blocked and methylated 5' terminal structure (referred later to as "cap" or "m(7)G-cap") in the transcription of silkworm CPV and human reovirus and vaccinia viruses that contain RNA polymerase in virus particles. Initial studies with viruses paved the way to discover the 5'-cap m(7)GpppNm structure present generally in cellular mRNAs of eukaryotes. I participated in those studies and was able to explain the pathway of cap synthesis and the significance of the 5' cap (and capping) in gene expression processes, including transcription and protein synthesis. In this review article I concentrate on the description of these initial studies that eventually led us to a new paradigm of mRNA capping.
Collapse
Affiliation(s)
- Yasuhiro FURUICHI
- GeneCare Research Institute Co., Ltd., Kanagawa, Japan
- Correspondence should be addressed: Y. Furuichi, GeneCare Research Institute Co., Ltd., 19-2 Kajiwara, Kamakura, Kanagawa 247-0063, Japan (e-mail: )
| |
Collapse
|
45
|
Fujimoto M, Kuninaka A, Yoshino H. Some Physical and Chemical Properties of Nuclease P1. ACTA ACUST UNITED AC 2014. [DOI: 10.1080/00021369.1975.10861894] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
46
|
Abstract
Members of the genus Orthoreovirus in the family Reoviridae are nonenveloped, icosahedral viruses. Their genomes contain 10 segments of double-stranded RNA (dsRNA). The orthoreoviruses are divided into two subgroups, the fusogenic and nonfusogenic reoviruses, based on the ability of the virus to induce cell-to-cell fusion. The fusogenic subgroup consists of the avian reovirus, baboon reovirus, pteropine reovirus, and reptilian reovirus, whereas the nonfusogenic subgroup consists of the prototypical mammalian reovirus (MRV) species. MRVs are highly tractable experimental models for studies of segmented dsRNA virus replication and pathogenesis. Moreover, MRVs can selectively kill tumor cells and have been evaluated as oncolytic agents in clinical trials. This review provides a brief overview of current knowledge on the virological features of MRVs.
Collapse
Affiliation(s)
- Takeshi Kobayashi
- International Research Center for Infectious Diseases, Research Institute for Microbial Diseases, Osaka University
| |
Collapse
|
47
|
The D10 decapping enzyme of vaccinia virus contributes to decay of cellular and viral mRNAs and to virulence in mice. J Virol 2013; 88:202-11. [PMID: 24155373 DOI: 10.1128/jvi.02426-13] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Posttranscriptional mechanisms are important for regulation of cellular and viral gene expression. The presence of the 5' cap structure m(7)G(5')ppp(5')Nm is a general feature of mRNAs that provides protection from exoribonuclease digestion and enhances translation. Vaccinia virus and other poxviruses encode enzymes for both cap synthesis and decapping. Decapping is mediated by two related enzymes, D9 and D10, which are synthesized before and after viral DNA replication, respectively. The timing of D10 synthesis correlates better with the shutdown of host gene expression, and deletion of this gene has been shown to cause persistence of host and viral mRNAs in infected cells. Here, we constructed specific mutant viruses in which translation of D10 was prevented by stop codons or activity of D10 was abrogated by catalytic site mutations, without other genomic alterations. Both mutants formed plaques of normal size and replicated to similar extents as the parental virus in monkey epithelial cells and mouse embryonic fibroblasts. The synthesis of viral proteins was slightly delayed, and cellular and viral mRNAs persisted longer in cells infected with the mutants compared to either the parental virus or clonal revertant. Despite the mild effects in vitro, both mutants were more attenuated than the revertants in intranasal and intraperitoneal mouse models, and less infectious virus was recovered from organs. In addition, there was less lung histopathology following intranasal infection with mutant viruses. These data suggest that the D10 decapping enzyme may help restrict antiviral responses by accelerating host mRNA degradation during poxvirus infection.
Collapse
|
48
|
Markussen T, Dahle MK, Tengs T, Løvoll M, Finstad ØW, Wiik-Nielsen CR, Grove S, Lauksund S, Robertsen B, Rimstad E. Sequence analysis of the genome of piscine orthoreovirus (PRV) associated with heart and skeletal muscle inflammation (HSMI) in Atlantic salmon (Salmo salar). PLoS One 2013; 8:e70075. [PMID: 23922911 PMCID: PMC3726481 DOI: 10.1371/journal.pone.0070075] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Accepted: 06/16/2013] [Indexed: 12/20/2022] Open
Abstract
Piscine orthoreovirus (PRV) is associated with heart- and skeletal muscle inflammation (HSMI) of farmed Atlantic salmon (Salmo salar). We have performed detailed sequence analysis of the PRV genome with focus on putative encoded proteins, compared with prototype strains from mammalian (MRV T3D)- and avian orthoreoviruses (ARV-138), and aquareovirus (GCRV-873). Amino acid identities were low for most gene segments but detailed sequence analysis showed that many protein motifs or key amino acid residues known to be central to protein function are conserved for most PRV proteins. For M-class proteins this included a proline residue in μ2 which, for MRV, has been shown to play a key role in both the formation and structural organization of virus inclusion bodies, and affect interferon-β signaling and induction of myocarditis. Predicted structural similarities in the inner core-forming proteins λ1 and σ2 suggest a conserved core structure. In contrast, low amino acid identities in the predicted PRV surface proteins μ1, σ1 and σ3 suggested differences regarding cellular interactions between the reovirus genera. However, for σ1, amino acid residues central for MRV binding to sialic acids, and cleavage- and myristoylation sites in μ1 required for endosomal membrane penetration during infection are partially or wholly conserved in the homologous PRV proteins. In PRV σ3 the only conserved element found was a zinc finger motif. We provide evidence that the S1 segment encoding σ3 also encodes a 124 aa (p13) protein, which appears to be localized to intracellular Golgi-like structures. The S2 and L2 gene segments are also potentially polycistronic, predicted to encode a 71 aa- (p8) and a 98 aa (p11) protein, respectively. It is concluded that PRV has more properties in common with orthoreoviruses than with aquareoviruses.
Collapse
Affiliation(s)
- Turhan Markussen
- Department of Laboratory Services, National Veterinary Institute, Oslo, Norway
| | - Maria K. Dahle
- Department of Laboratory Services, National Veterinary Institute, Oslo, Norway
| | - Torstein Tengs
- Department of Laboratory Services, National Veterinary Institute, Oslo, Norway
| | - Marie Løvoll
- Department of Laboratory Services, National Veterinary Institute, Oslo, Norway
| | - Øystein W. Finstad
- Department of Food Safety and Infection Biology, Norwegian School of Veterinary Science, Oslo, Norway
| | | | - Søren Grove
- Department of Laboratory Services, National Veterinary Institute, Oslo, Norway
| | - Silje Lauksund
- Norwegian College of Fishery Science, University of Tromsø, Tromsø, Norway
| | - Børre Robertsen
- Norwegian College of Fishery Science, University of Tromsø, Tromsø, Norway
| | - Espen Rimstad
- Department of Food Safety and Infection Biology, Norwegian School of Veterinary Science, Oslo, Norway
- * E-mail:
| |
Collapse
|
49
|
Darnell JE. Reflections on the history of pre-mRNA processing and highlights of current knowledge: a unified picture. RNA (NEW YORK, N.Y.) 2013; 19:443-60. [PMID: 23440351 PMCID: PMC3677254 DOI: 10.1261/rna.038596.113] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Several strong conclusions emerge concerning pre-mRNA processing from both old and newer experiments. The RNAPII complex is involved with pre-mRNA processing through binding of processing proteins to the CTD (carboxyl terminal domain) of the largest RNAPII subunit. These interactions are necessary for efficient processing, but whether factor binding to the CTD and delivery to splicing sites is obligatory or facilitatory is unsettled. Capping, addition of an m(7)Gppp residue (cap) to the initial transcribed residue of a pre-mRNA, occurs within seconds. Splicing of pre-mRNA by spliceosomes at particular sites is most likely committed during transcription by the binding of initiating processing factors and ∼50% of the time is completed in mammalian cells before completion of the primary transcript. This fact has led to an outpouring in the literature about "cotranscriptional splicing." However splicing requires several minutes for completion and can take longer. The RNAPII complex moves through very long introns and also through regions dense with alternating exons and introns at an average rate of ∼3 kb per min and is, therefore, not likely detained at each splice site for more than a few seconds, if at all. Cleavage of the primary transcript at the 3' end and polyadenylation occurs within 30 sec or less at recognized polyA sites, and the majority of newly polyadenylated pre-mRNA molecules are much larger than the average mRNA. Finally, it seems quite likely that the nascent RNA most often remains associated with the chromosomal locus being transcribed until processing is complete, possibly acquiring factors related to the transport of the new mRNA to the cytoplasm.
Collapse
Affiliation(s)
- James E Darnell
- Laboratory of Molecular Cell Biology, Rockefeller University, New York, NY 10065, USA.
| |
Collapse
|
50
|
Sahin E, Egger ME, McMasters KM, Zhou HS. Development of Oncolytic Reovirus for Cancer Therapy. ACTA ACUST UNITED AC 2013. [DOI: 10.4236/jct.2013.46127] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|