1
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Holmes EC. The Emergence and Evolution of SARS-CoV-2. Annu Rev Virol 2024; 11:21-42. [PMID: 38631919 DOI: 10.1146/annurev-virology-093022-013037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2024]
Abstract
The origin of SARS-CoV-2 has evoked heated debate and strong accusations, yet seemingly little resolution. I review the scientific evidence on the origin of SARS-CoV-2 and its subsequent spread through the human population. The available data clearly point to a natural zoonotic emergence within, or closely linked to, the Huanan Seafood Wholesale Market in Wuhan. There is no direct evidence linking the emergence of SARS-CoV-2 to laboratory work conducted at the Wuhan Institute of Virology. The subsequent global spread of SARS-CoV-2 was characterized by a gradual adaptation to humans, with dual increases in transmissibility and virulence until the emergence of the Omicron variant. Of note has been the frequent transmission of SARS-CoV-2 from humans to other animals, marking it as a strongly host generalist virus. Unless lessons from the origin of SARS-CoV-2 are learned, it is inevitable that more zoonotic events leading to more epidemics and pandemics will plague human populations.
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Affiliation(s)
- Edward C Holmes
- Sydney Institute for Infectious Diseases, School of Medical Sciences, The University of Sydney, Sydney, New South Wales, Australia;
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2
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Peña-Hernández MA, Alfajaro MM, Filler RB, Moriyama M, Keeler EL, Ranglin ZE, Kong Y, Mao T, Menasche BL, Mankowski MC, Zhao Z, Vogels CBF, Hahn AM, Kalinich CC, Zhang S, Huston N, Wan H, Araujo-Tavares R, Lindenbach BD, Homer R, Pyle AM, Martinez DR, Grubaugh ND, Israelow B, Iwasaki A, Wilen CB. SARS-CoV-2-related bat viruses evade human intrinsic immunity but lack efficient transmission capacity. Nat Microbiol 2024; 9:2038-2050. [PMID: 39075235 DOI: 10.1038/s41564-024-01765-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Accepted: 06/19/2024] [Indexed: 07/31/2024]
Abstract
Circulating bat coronaviruses represent a pandemic threat. However, our understanding of bat coronavirus pathogenesis and transmission potential is limited by the lack of phenotypically characterized strains. We created molecular clones for the two closest known relatives of SARS-CoV-2, BANAL-52 and BANAL-236. We demonstrated that BANAL-CoVs and SARS-CoV-2 have similar replication kinetics in human bronchial epithelial cells. However, BANAL-CoVs have impaired replication in human nasal epithelial cells and in the upper airway of mice. We also observed reduced pathogenesis in mice and diminished transmission in hamsters. Further, we observed that diverse bat coronaviruses evade interferon and downregulate major histocompatibility complex class I. Collectively, our study demonstrates that despite high genetic similarity across bat coronaviruses, prediction of pandemic potential of a virus necessitates functional characterization. Finally, the restriction of bat coronavirus replication in the upper airway highlights that transmission potential and innate immune restriction can be uncoupled in this high-risk family of emerging viruses.
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Affiliation(s)
- Mario A Peña-Hernández
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, USA
- Department of Laboratory Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Mia Madel Alfajaro
- Department of Laboratory Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Renata B Filler
- Department of Laboratory Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Miyu Moriyama
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
| | - Emma L Keeler
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, USA
- Department of Laboratory Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Zara E Ranglin
- Department of Laboratory Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Yong Kong
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
| | - Tianyang Mao
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
| | - Bridget L Menasche
- Department of Laboratory Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Madeleine C Mankowski
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
- Department of Laboratory Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Zhe Zhao
- Department of Laboratory Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Chantal B F Vogels
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, USA
| | - Anne M Hahn
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, USA
| | - Chaney C Kalinich
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, USA
| | - Shuo Zhang
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, USA
- Department of Laboratory Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Nicholas Huston
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - Han Wan
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - Rafael Araujo-Tavares
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - Brett D Lindenbach
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, USA
| | - Robert Homer
- Department of Pathology, Yale School of Medicine, New Haven, CT, USA
| | - Anna Marie Pyle
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
- Department of Chemistry, Yale University, New Haven, CT, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - David R Martinez
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
| | - Nathan D Grubaugh
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, USA
| | - Benjamin Israelow
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
- Department of Internal Medicine, Section of Infectious Diseases, Yale School of Medicine, New Haven, CT, USA
| | - Akiko Iwasaki
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA.
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, USA.
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA.
- Howard Hughes Medical Institute, Chevy Chase, MD, USA.
| | - Craig B Wilen
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA.
- Department of Laboratory Medicine, Yale School of Medicine, New Haven, CT, USA.
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3
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Xiao Y, Wang H, Wang H, Dong J, Peng R, Zhao L. Inactivation efficacy and mechanism of 9.375 GHz electromagnetic wave on coronavirus. Virology 2024; 598:110165. [PMID: 39013305 DOI: 10.1016/j.virol.2024.110165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2024] [Revised: 06/03/2024] [Accepted: 06/30/2024] [Indexed: 07/18/2024]
Abstract
Epidemics caused by pathogenic viruses are a severe threat to public health worldwide. Electromagnetic waves are a type of noncontact and nonionizing radiation technology that has emerged as an effective tool for inactivating bacterial pathogens. In this study, we used a 9.375 GHz electromagnetic wave to study the inactivation effect and mechanism of electromagnetic waves on MHV-A59, a substitute virus for pathogenic human coronavirus, and to evaluate the inactivation efficiency on different surface materials. We showed that 9.375 GHz electromagnetic waves inactivate MHV-A59 by destroying viral particles, envelopes, or genomes. We also found that 9.375 GHz electromagnetic waves can decrease the infectivity of viruses on the surface of inanimate materials such as plastic, glass, cloth, and wood. In conclusion, our results suggested that the 9.375 GHz electromagnetic wave is a promising disinfection technique for preventing the spread and infection of pathogenic viruses.
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Affiliation(s)
- Yi Xiao
- School of Basic Medical Sciences, Anhui Medical University, Yard 81, Meishan Road, Hefei, 230032, PR China; Beijing Institute of Radiation Medicine, Yard 27, Taiping Road, Beijing 100850, PR China
| | - Hui Wang
- Beijing Institute of Radiation Medicine, Yard 27, Taiping Road, Beijing 100850, PR China
| | - Haoyu Wang
- Beijing Institute of Radiation Medicine, Yard 27, Taiping Road, Beijing 100850, PR China
| | - Ji Dong
- Beijing Institute of Radiation Medicine, Yard 27, Taiping Road, Beijing 100850, PR China
| | - Ruiyun Peng
- School of Basic Medical Sciences, Anhui Medical University, Yard 81, Meishan Road, Hefei, 230032, PR China; Beijing Institute of Radiation Medicine, Yard 27, Taiping Road, Beijing 100850, PR China.
| | - Li Zhao
- School of Basic Medical Sciences, Anhui Medical University, Yard 81, Meishan Road, Hefei, 230032, PR China; Beijing Institute of Radiation Medicine, Yard 27, Taiping Road, Beijing 100850, PR China.
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4
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Ujike M, Suzuki T. Progress of research on coronaviruses and toroviruses in large domestic animals using reverse genetics systems. Vet J 2024; 305:106122. [PMID: 38641200 DOI: 10.1016/j.tvjl.2024.106122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 03/24/2024] [Accepted: 04/14/2024] [Indexed: 04/21/2024]
Abstract
The generation of genetically engineered recombinant viruses from modified DNA/RNA is commonly referred to as reverse genetics, which allows the introduction of desired mutations into the viral genome. Reverse genetics systems (RGSs) are powerful tools for studying fundamental viral processes, mechanisms of infection, pathogenesis and vaccine development. However, establishing RGS for coronaviruses (CoVs) and toroviruses (ToVs), which have the largest genomes among vertebrate RNA viruses, is laborious and hampered by technical constraints. Hence, little research has focused on animal CoVs and ToVs using RGSs, especially in large domestic animals such as pigs and cattle. In the last decade, however, studies of porcine CoVs and bovine ToVs using RGSs have been reported. In addition, the coronavirus disease-2019 pandemic has prompted the development of new and simple CoV RGSs, which will accelerate RGS-based research on animal CoVs and ToVs. In this review, we summarise the general characteristics of CoVs and ToVs, the RGSs available for CoVs and ToVs and the progress made in the last decade in RGS-based research on porcine CoVs and bovine ToVs.
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Affiliation(s)
- Makoto Ujike
- Laboratory of Veterinary Infectious Diseases, Faculty of Veterinary Medicine, Nippon Veterinary and Life Science University, 1-7-1 Kyonan-cho, Musashino, Tokyo 180-8602, Japan; Research Center for Animal Life Science, Nippon Veterinary and Life Science University, 1-7-1 Kyonan-cho, Musashino, Tokyo 180-8602, Japan.
| | - Tohru Suzuki
- Division of Zoonosis Research, Sapporo Research Station, National Institute of Animal Health, NARO, Sapporo, Hokkaido 062-0045, Japan
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Wu G, Li Q, Dai J, Mao G, Ma Y. Design and Application of Biosafe Coronavirus Engineering Systems without Virulence. Viruses 2024; 16:659. [PMID: 38793541 PMCID: PMC11126016 DOI: 10.3390/v16050659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Revised: 04/15/2024] [Accepted: 04/18/2024] [Indexed: 05/26/2024] Open
Abstract
In the last twenty years, three deadly zoonotic coronaviruses (CoVs)-namely, severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and SARS-CoV-2-have emerged. They are considered highly pathogenic for humans, particularly SARS-CoV-2, which caused the 2019 CoV disease pandemic (COVID-19), endangering the lives and health of people globally and causing unpredictable economic losses. Experiments on wild-type viruses require biosafety level 3 or 4 laboratories (BSL-3 or BSL-4), which significantly hinders basic virological research. Therefore, the development of various biosafe CoV systems without virulence is urgently needed to meet the requirements of different research fields, such as antiviral and vaccine evaluation. This review aimed to comprehensively summarize the biosafety of CoV engineering systems. These systems combine virological foundations with synthetic genomics techniques, enabling the development of efficient tools for attenuated or non-virulent vaccines, the screening of antiviral drugs, and the investigation of the pathogenic mechanisms of novel microorganisms.
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Affiliation(s)
- Guoqiang Wu
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China; (G.W.); (Q.L.); (J.D.)
- School of Pharmacy, Faculty of Medicine, Macau University of Science and Technology, Macau SAR 999078, China
| | - Qiaoyu Li
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China; (G.W.); (Q.L.); (J.D.)
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Junbiao Dai
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China; (G.W.); (Q.L.); (J.D.)
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Key Laboratory of Synthetic Biology, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China
| | - Guobin Mao
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China; (G.W.); (Q.L.); (J.D.)
| | - Yingxin Ma
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China; (G.W.); (Q.L.); (J.D.)
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6
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Kubinski HC, Despres HW, Johnson BA, Schmidt MM, Jaffrani SA, Mills MG, Lokugamage K, Dumas CM, Shirley DJ, Estes LK, Pekosz A, Crothers JW, Roychoudhury P, Greninger AL, Jerome KR, Di Genova BM, Walker DH, Ballif BA, Ladinsky MS, Bjorkman PJ, Menachery VD, Bruce EA. Variant mutation in SARS-CoV-2 nucleocapsid enhances viral infection via altered genomic encapsidation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.08.584120. [PMID: 38559000 PMCID: PMC10979914 DOI: 10.1101/2024.03.08.584120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
The evolution of SARS-CoV-2 variants and their respective phenotypes represents an important set of tools to understand basic coronavirus biology as well as the public health implications of individual mutations in variants of concern. While mutations outside of Spike are not well studied, the entire viral genome is undergoing evolutionary selection, particularly the central disordered linker region of the nucleocapsid (N) protein. Here, we identify a mutation (G215C), characteristic of the Delta variant, that introduces a novel cysteine into this linker domain, which results in the formation of a disulfide bond and a stable N-N dimer. Using reverse genetics, we determined that this cysteine residue is necessary and sufficient for stable dimer formation in a WA1 SARS-CoV-2 background, where it results in significantly increased viral growth both in vitro and in vivo. Finally, we demonstrate that the N:G215C virus packages more nucleocapsid per virion and that individual virions are larger, with elongated morphologies.
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Affiliation(s)
- Hannah C. Kubinski
- Department of Microbiology and Molecular Genetics, Robert Larner, M.D. College of Medicine, University of Vermont, Burlington VT, 05405, USA
| | - Hannah W. Despres
- Department of Microbiology and Molecular Genetics, Robert Larner, M.D. College of Medicine, University of Vermont, Burlington VT, 05405, USA
| | - Bryan A. Johnson
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas, USA
- Institute for Human Infection and Immunity, University of Texas Medical Branch, Galveston, TX, USA
- Center for Tropical Diseases, University of Texas Medical Branch, Galveston, TX, USA
| | - Madaline M. Schmidt
- Department of Microbiology and Molecular Genetics, Robert Larner, M.D. College of Medicine, University of Vermont, Burlington VT, 05405, USA
| | - Sara A. Jaffrani
- Department of Microbiology and Molecular Genetics, Robert Larner, M.D. College of Medicine, University of Vermont, Burlington VT, 05405, USA
| | - Margaret G. Mills
- Virology Division, Department of Laboratory Medicine and Pathology, University of Washington, Seattle WA 98195, USA
| | - Kumari Lokugamage
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Caroline M. Dumas
- Department of Biology, University of Vermont 109 Carrigan Drive, 120A Marsh Life Sciences, Burlington VT 05404, USA
| | - David J. Shirley
- Faraday, Inc. Data Science Department. Burlington VT, 05405, USA
| | - Leah K. Estes
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Andrew Pekosz
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, The Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Jessica W. Crothers
- Department of Pathology and Laboratory Medicine, Robert Larner, MD College of Medicine, University of Vermont, Burlington, VT, USA
| | - Pavitra Roychoudhury
- Virology Division, Department of Laboratory Medicine and Pathology, University of Washington, Seattle WA 98195, USA
| | - Alexander L. Greninger
- Virology Division, Department of Laboratory Medicine and Pathology, University of Washington, Seattle WA 98195, USA
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle WA 98109, USA
| | - Keith R. Jerome
- Virology Division, Department of Laboratory Medicine and Pathology, University of Washington, Seattle WA 98195, USA
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle WA 98109, USA
| | - Bruno Martorelli Di Genova
- Department of Microbiology and Molecular Genetics, Robert Larner, M.D. College of Medicine, University of Vermont, Burlington VT, 05405, USA
| | - David H. Walker
- Department of Pathology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Bryan A. Ballif
- Department of Biology, University of Vermont 109 Carrigan Drive, 120A Marsh Life Sciences, Burlington VT 05404, USA
| | - Mark S. Ladinsky
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA. 91125, USA
| | - Pamela J. Bjorkman
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA. 91125, USA
| | - Vineet D. Menachery
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas, USA
- World Reference Center of Emerging Viruses and Arboviruses, University of Texas Medical Branch, Galveston, Texas, USA
- Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, Galveston, Texas, USA
| | - Emily A. Bruce
- Department of Microbiology and Molecular Genetics, Robert Larner, M.D. College of Medicine, University of Vermont, Burlington VT, 05405, USA
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Cai HL, Huang YW. Reverse genetics systems for SARS-CoV-2: Development and applications. Virol Sin 2023; 38:837-850. [PMID: 37832720 PMCID: PMC10786661 DOI: 10.1016/j.virs.2023.10.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Accepted: 10/07/2023] [Indexed: 10/15/2023] Open
Abstract
The recent emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused serious harm to human health and struck a blow to global economic development. Research on SARS-CoV-2 has greatly benefited from the use of reverse genetics systems, which have been established to artificially manipulate the viral genome, generating recombinant and reporter infectious viruses or biosafety level 2 (BSL-2)-adapted non-infectious replicons with desired modifications. These tools have been instrumental in studying the molecular biological characteristics of the virus, investigating antiviral therapeutics, and facilitating the development of attenuated vaccine candidates. Here, we review the construction strategies, development, and applications of reverse genetics systems for SARS-CoV-2, which may be applied to other CoVs as well.
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Affiliation(s)
- Hou-Li Cai
- Department of Veterinary Medicine, Zhejiang University, Hangzhou, 310058, China
| | - Yao-Wei Huang
- Department of Veterinary Medicine, Zhejiang University, Hangzhou, 310058, China; State Key Laboratory for Animal Disease Control and Prevention, South China Agricultural University, Guangzhou, 510642, China; Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China.
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8
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Lin CH, Hsieh FC, Chang YC, Yang CY, Hsu HW, Yang CC, Tam HMH, Wu HY. Targeting the conserved coronavirus octamer motif GGAAGAGC is a strategy for the development of coronavirus vaccine. Virol J 2023; 20:267. [PMID: 37968733 PMCID: PMC10652495 DOI: 10.1186/s12985-023-02231-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Accepted: 11/06/2023] [Indexed: 11/17/2023] Open
Abstract
BACKGROUND Coronaviruses are pathogens of humans and animals that cause widespread and costly diseases. The development of effective strategies to combat the threat of coronaviruses is therefore a top priority. The conserved coronavirus octamer motif 5'GGAAGAGC3' exists in the 3' untranslated region of all identified coronaviruses. In the current study, we aimed to examine whether targeting the coronavirus octamer motif GGAAGAGC is a promising approach to develop coronavirus vaccine. METHODS Plaque assays were used to determine the titers of mouse hepatitis virus (MHV)-A59 octamer mutant (MHVoctm) and wild-type (wt) MHV-A59 (MHVwt). Western blotting was used for the determination of translation efficiency of MHVoctm and MHVwt. Plaque assays and RT-qPCR were employed to examine whether MHVoctm was more sensitive to interferon treatment than MHVwt. Weight loss, clinical signs, survival rate, viral RNA detection and histopathological examination were used to evaluate whether MHVoctm was a vaccine candidate against MHVwt infection in BALB/c mice. RESULTS In this study, we showed that (i) the MHVoctm with mutation of coronavirus octamer was able to grow to high titers but attenuated in mice, (ii) with the reduced multiplicity of infection (MOI), the difference in gene expression between MHVoctm and MHVwt became more evident in cultured cells, (iii) MHVoctm was more sensitive to interferon treatment than MHVwt and (iv) mice inoculated with MHVoctm were protected from MHVwt infection. CONCLUSIONS Based on the results obtained from cultured cells, it was suggested that the synergistic effects of octamer mutation, multiplicity of infection and immune response may be a mechanism explaining the distinct phenotypes of octamer-mutated coronavirus in cell culture and mice. In addition, targeting the conserved coronavirus octamer motif is a strategy for development of coronavirus vaccine. Since the conserved octamer exists in all coronaviruses, this strategy of targeting the conserved octamer motif can also be applied to other human and animal coronaviruses for the development of coronavirus vaccines, especially the emergence of novel coronaviruses such as SARS-CoV-2, saving time and cost for vaccine development and disease control.
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Grants
- 109-2313-B-005 -013 -MY3, 110-2327-B-005 -003, 111-2327-B-005 -003 and 112-2313-B-005-041 National Science and Technology Council, Taiwan, R.O.C.
- 109-2313-B-005 -013 -MY3, 110-2327-B-005 -003, 111-2327-B-005 -003 and 112-2313-B-005-041 National Science and Technology Council, Taiwan, R.O.C.
- 109-2313-B-005 -013 -MY3, 110-2327-B-005 -003, 111-2327-B-005 -003 and 112-2313-B-005-041 National Science and Technology Council, Taiwan, R.O.C.
- 109-2313-B-005 -013 -MY3, 110-2327-B-005 -003, 111-2327-B-005 -003 and 112-2313-B-005-041 National Science and Technology Council, Taiwan, R.O.C.
- 109-2313-B-005 -013 -MY3, 110-2327-B-005 -003, 111-2327-B-005 -003 and 112-2313-B-005-041 National Science and Technology Council, Taiwan, R.O.C.
- 109-2313-B-005 -013 -MY3, 110-2327-B-005 -003, 111-2327-B-005 -003 and 112-2313-B-005-041 National Science and Technology Council, Taiwan, R.O.C.
- 109-2313-B-005 -013 -MY3, 110-2327-B-005 -003, 111-2327-B-005 -003 and 112-2313-B-005-041 National Science and Technology Council, Taiwan, R.O.C.
- 109-2313-B-005 -013 -MY3, 110-2327-B-005 -003, 111-2327-B-005 -003 and 112-2313-B-005-041 National Science and Technology Council, Taiwan, R.O.C.
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Affiliation(s)
- Ching-Hung Lin
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Feng-Cheng Hsieh
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Yu-Chia Chang
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Cheng-Yao Yang
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Hsuan-Wei Hsu
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Chun-Chun Yang
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Hon-Man-Herman Tam
- Department of Veterinary Medicine, College of Veterinary Medicine, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Hung-Yi Wu
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University, Taichung, 40227, Taiwan.
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Lin CH, Chen B, Chao DY, Hsieh FC, Yang CC, Hsu HW, Tam HMH, Wu HY. Unveiling the biology of defective viral genomes in vitro and in vivo: implications for gene expression and pathogenesis of coronavirus. Virol J 2023; 20:225. [PMID: 37803357 PMCID: PMC10559480 DOI: 10.1186/s12985-023-02189-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 09/19/2023] [Indexed: 10/08/2023] Open
Abstract
BACKGROUND Defective viral genome (DVG) is a truncated version of the full-length virus genome identified in most RNA viruses during infection. The synthesis of DVGs in coronavirus has been suggested; however, the fundamental characteristics of coronavirus DVGs in gene expression and pathogenesis have not been systematically analyzed. METHODS Nanopore direct RNA sequencing was used to investigate the characteristics of coronavirus DVGs in gene expression including reproducibility, abundance, species and genome structures for bovine coronavirus in cells, and for mouse hepatitis virus (MHV)-A59 (a mouse coronavirus) in cells and in mice. The MHV-A59 full-length genomic cDNAs (~ 31 kilobases) were in vitro constructed to experimentally validate the origin of coronavirus DVG. The synthesis of DVGs was also experimentally identified by RT-PCR followed by sequencing. In addition, the alterations of DVGs in amounts and species under different infection environments and selection pressures including the treatment of antiviral remdesivir and interferon were evaluated based on the banding patterns by RT-PCR. RESULTS The results are as follows: (i) the structures of DVGs are with diversity, (ii) DVGs are overall synthesized with moderate (MHV-A59 in cells) to high (BCoV in cells and MHV-A59 in mice) reproducibility under regular infection with the same virus inoculum, (iii) DVGs can be synthesized from the full-length coronavirus genome, (iv) the sequences flanking the recombination point of DVGs are AU-rich and thus may contribute to the recombination events during gene expression, (v) the species and amounts of DVG are altered under different infection environments, and (vi) the biological nature of DVGs between in vitro and in vivo is similar. CONCLUSIONS The identified biological characteristics of coronavirus DVGs in terms of abundance, reproducibility, and variety extend the current model for coronavirus gene expression. In addition, the biological features of alterations in amounts and species of coronavirus DVGs under different infection environments may assist the coronavirus to adapt to the altered environments for virus fitness and may contribute to the coronavirus pathogenesis. Consequently, the unveiled biological features may assist the community to study the gene expression mechanisms of DVGs and their roles in pathogenesis, contributing to the development of antiviral strategy and public health.
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Affiliation(s)
- Ching-Hung Lin
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University, Taichung, 40227, Taiwan
| | - BoJia Chen
- Doctoral Program in Microbial Genomics, National Chung Hsing University and Academia Sinica, Taichung, 40227, Taiwan
| | - Day-Yu Chao
- Doctoral Program in Microbial Genomics, National Chung Hsing University and Academia Sinica, Taichung, 40227, Taiwan
- Graduate Institute of Microbiology and Public Health, College of Veterinary Medicine, National Chung Hsing University, Taichung, 40227, Taiwan
- Department of Post-Baccalaureate Medicine, College of Medicine, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Feng-Cheng Hsieh
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Chun-Chun Yang
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Hsuan-Wei Hsu
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Hon-Man-Herman Tam
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Hung-Yi Wu
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University, Taichung, 40227, Taiwan.
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10
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Hou YJ, Chiba S, Leist SR, Meganck RM, Martinez DR, Schäfer A, Catanzaro NJ, Sontake V, West A, Edwards CE, Yount B, Lee RE, Gallant SC, Zost SJ, Powers J, Adams L, Kong EF, Mattocks M, Tata A, Randell SH, Tata PR, Halfmann P, Crowe JE, Kawaoka Y, Baric RS. Host range, transmissibility and antigenicity of a pangolin coronavirus. Nat Microbiol 2023; 8:1820-1833. [PMID: 37749254 PMCID: PMC10522490 DOI: 10.1038/s41564-023-01476-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Accepted: 08/14/2023] [Indexed: 09/27/2023]
Abstract
The pathogenic and cross-species transmission potential of SARS-CoV-2-related coronaviruses (CoVs) remain poorly characterized. Here we recovered a wild-type pangolin (Pg) CoV GD strain including derivatives encoding reporter genes using reverse genetics. In primary human cells, PgCoV replicated efficiently but with reduced fitness and showed less efficient transmission via airborne route compared with SARS-CoV-2 in hamsters. PgCoV was potently inhibited by US Food and Drug Administration approved drugs, and neutralized by COVID-19 patient sera and SARS-CoV-2 therapeutic antibodies in vitro. A pan-Sarbecovirus antibody and SARS-CoV-2 S2P recombinant protein vaccine protected BALB/c mice from PgCoV infection. In K18-hACE2 mice, PgCoV infection caused severe clinical disease, but mice were protected by a SARS-CoV-2 human antibody. Efficient PgCoV replication in primary human cells and hACE2 mice, coupled with a capacity for airborne spread, highlights an emergence potential. However, low competitive fitness, pre-immune humans and the benefit of COVID-19 countermeasures should impede its ability to spread globally in human populations.
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Affiliation(s)
- Yixuan J Hou
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Moderna Inc., Cambridge, MA, USA
| | - Shiho Chiba
- Influenza Research Institute, Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI, USA
| | - Sarah R Leist
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Rita M Meganck
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - David R Martinez
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Alexandra Schäfer
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Nicholas J Catanzaro
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Vishwaraj Sontake
- Department of Cell Biology, Regeneration Next Initiative, Duke University Medical Center, Durham, NC, USA
| | - Ande West
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Catlin E Edwards
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Boyd Yount
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Rhianna E Lee
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Samuel C Gallant
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Seth J Zost
- Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, TN, USA
| | - John Powers
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Lily Adams
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Edgar F Kong
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Melissa Mattocks
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Aleksandra Tata
- Department of Cell Biology, Regeneration Next Initiative, Duke University Medical Center, Durham, NC, USA
| | - Scott H Randell
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Purushothama R Tata
- Department of Cell Biology, Regeneration Next Initiative, Duke University Medical Center, Durham, NC, USA
| | - Peter Halfmann
- Influenza Research Institute, Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI, USA
| | - James E Crowe
- Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Yoshihiro Kawaoka
- Influenza Research Institute, Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI, USA
- Division of Virology, Department of Microbiology and Immunology, Institute of Medical Science, University of Tokyo, Tokyo, Japan
| | - Ralph S Baric
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
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11
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Grimes SL, Choi YJ, Banerjee A, Small G, Anderson-Daniels J, Gribble J, Pruijssers AJ, Agostini ML, Abu-Shmais A, Lu X, Darst SA, Campbell E, Denison MR. A mutation in the coronavirus nsp13-helicase impairs enzymatic activity and confers partial remdesivir resistance. mBio 2023; 14:e0106023. [PMID: 37338298 PMCID: PMC10470589 DOI: 10.1128/mbio.01060-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 05/04/2023] [Indexed: 06/21/2023] Open
Abstract
Coronaviruses (CoVs) encode nonstructural proteins 1-16 (nsps 1-16) which form replicase complexes that mediate viral RNA synthesis. Remdesivir (RDV) is an adenosine nucleoside analog antiviral that inhibits CoV RNA synthesis. RDV resistance mutations have been reported only in the nonstructural protein 12 RNA-dependent RNA polymerase (nsp12-RdRp). We here show that a substitution mutation in the nsp13-helicase (nsp13-HEL A335V) of the betacoronavirus murine hepatitis virus (MHV) that was selected during passage with the RDV parent compound confers partial RDV resistance independently and additively when expressed with co-selected RDV resistance mutations in the nsp12-RdRp. The MHV A335V substitution did not enhance replication or competitive fitness compared to WT MHV and remained sensitive to the active form of the cytidine nucleoside analog antiviral molnupiravir (MOV). Biochemical analysis of the SARS-CoV-2 helicase encoding the homologous substitution (A336V) demonstrates that the mutant protein retained the ability to associate with the core replication proteins nsps 7, 8, and 12 but had impaired helicase unwinding and ATPase activity. Together, these data identify a novel determinant of nsp13-HEL enzymatic activity, define a new genetic pathway for RDV resistance, and demonstrate the importance of surveillance for and testing of helicase mutations that arise in SARS-CoV-2 genomes. IMPORTANCE Despite the development of effective vaccines against COVID-19, the continued circulation and emergence of new variants support the need for antivirals such as RDV. Understanding pathways of antiviral resistance is essential for surveillance of emerging variants, development of combination therapies, and for identifying potential new targets for viral inhibition. We here show a novel RDV resistance mutation in the CoV helicase also impairs helicase functions, supporting the importance of studying the individual and cooperative functions of the replicase nonstructural proteins 7-16 during CoV RNA synthesis. The homologous nsp13-HEL mutation (A336V) has been reported in the GISAID database of SARS-CoV-2 genomes, highlighting the importance of surveillance of and genetic testing for nucleoside analog resistance in the helicase.
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Affiliation(s)
- Samantha L. Grimes
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Young J. Choi
- Laboratory of Molecular Biophysics, The Rockefeller University, New York, New York, USA
| | - Anoosha Banerjee
- Laboratory of Molecular Biophysics, The Rockefeller University, New York, New York, USA
- Tri-Institutional Program in Chemical Biology, The Rockefeller University, New York, New York, USA
| | - Gabriel Small
- Laboratory of Molecular Biophysics, The Rockefeller University, New York, New York, USA
| | - Jordan Anderson-Daniels
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Jennifer Gribble
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Andrea J. Pruijssers
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection, Immunology and Inflammation, Nashville, Tennessee, USA
| | - Maria L. Agostini
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Alexandra Abu-Shmais
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Xiaotao Lu
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Seth A. Darst
- Laboratory of Molecular Biophysics, The Rockefeller University, New York, New York, USA
| | - Elizabeth Campbell
- Laboratory of Molecular Biophysics, The Rockefeller University, New York, New York, USA
| | - Mark R. Denison
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection, Immunology and Inflammation, Nashville, Tennessee, USA
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12
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Taha TY, Chen IP, Hayashi JM, Tabata T, Walcott K, Kimmerly GR, Syed AM, Ciling A, Suryawanshi RK, Martin HS, Bach BH, Tsou CL, Montano M, Khalid MM, Sreekumar BK, Renuka Kumar G, Wyman S, Doudna JA, Ott M. Rapid assembly of SARS-CoV-2 genomes reveals attenuation of the Omicron BA.1 variant through NSP6. Nat Commun 2023; 14:2308. [PMID: 37085489 PMCID: PMC10120482 DOI: 10.1038/s41467-023-37787-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 03/31/2023] [Indexed: 04/23/2023] Open
Abstract
Although the SARS-CoV-2 Omicron variant (BA.1) spread rapidly across the world and effectively evaded immune responses, its viral fitness in cell and animal models was reduced. The precise nature of this attenuation remains unknown as generating replication-competent viral genomes is challenging because of the length of the viral genome (~30 kb). Here, we present a plasmid-based viral genome assembly and rescue strategy (pGLUE) that constructs complete infectious viruses or noninfectious subgenomic replicons in a single ligation reaction with >80% efficiency. Fully sequenced replicons and infectious viral stocks can be generated in 1 and 3 weeks, respectively. By testing a series of naturally occurring viruses as well as Delta-Omicron chimeric replicons, we show that Omicron nonstructural protein 6 harbors critical attenuating mutations, which dampen viral RNA replication and reduce lipid droplet consumption. Thus, pGLUE overcomes remaining barriers to broadly study SARS-CoV-2 replication and reveals deficits in nonstructural protein function underlying Omicron attenuation.
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Affiliation(s)
- Taha Y Taha
- Gladstone Institutes, San Francisco, CA, USA.
| | - Irene P Chen
- Gladstone Institutes, San Francisco, CA, USA
- Department of Medicine, University of California, San Francisco, CA, USA
| | | | | | | | | | - Abdullah M Syed
- Gladstone Institutes, San Francisco, CA, USA
- Innovative Genomics Institute, University of California, Berkeley, CA, USA
| | - Alison Ciling
- Gladstone Institutes, San Francisco, CA, USA
- Innovative Genomics Institute, University of California, Berkeley, CA, USA
| | | | - Hannah S Martin
- Gladstone Institutes, San Francisco, CA, USA
- Department of Chemistry, University of California, Berkeley, CA, USA
| | - Bryan H Bach
- Innovative Genomics Institute, University of California, Berkeley, CA, USA
| | | | | | | | | | | | - Stacia Wyman
- Innovative Genomics Institute, University of California, Berkeley, CA, USA
| | - Jennifer A Doudna
- Gladstone Institutes, San Francisco, CA, USA
- Innovative Genomics Institute, University of California, Berkeley, CA, USA
- Department of Chemistry, University of California, Berkeley, CA, USA
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
- Howard Hughes Medical Institute, University of California, Berkeley, CA, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, CA, USA
| | - Melanie Ott
- Gladstone Institutes, San Francisco, CA, USA.
- Department of Medicine, University of California, San Francisco, CA, USA.
- Chan Zuckerberg Biohub - San Francisco, San Francisco, CA, USA.
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13
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Alwine JC, Casadevall A, Enquist LW, Goodrum FD, Imperiale MJ. A Critical Analysis of the Evidence for the SARS-CoV-2 Origin Hypotheses. mSphere 2023; 8:e0011923. [PMID: 36897078 PMCID: PMC10117112 DOI: 10.1128/msphere.00119-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023] Open
Abstract
When humans experience a new, devastating viral infection such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), significant challenges arise. How should individuals as well as societies respond to the situation? One of the primary questions concerns the origin of the SARS-CoV-2 virus that infected and was transmitted efficiently among humans, resulting in a pandemic. At first glance, the question appears straightforward to answer. However, the origin of SARS-CoV-2 has been the topic of substantial debate primarily because we do not have access to some relevant data. At least two major hypotheses have been suggested: a natural origin through zoonosis followed by sustained human-to-human spread or the introduction of a natural virus into humans from a laboratory source. Here, we summarize the scientific evidence that informs this debate to provide our fellow scientists and the public with the tools to join the discussion in a constructive and informed manner. Our goal is to dissect the evidence to make it more accessible to those interested in this important problem. The engagement of a broad representation of scientists is critical to ensure that the public and policy-makers can draw on relevant expertise in navigating this controversy.
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Affiliation(s)
- James C. Alwine
- Department of Cancer Biology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Immunobiology, University of Arizona, Tucson, Arizona, USA
| | - Arturo Casadevall
- Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, USA
| | - Lynn W. Enquist
- Department of Immunobiology, University of Arizona, Tucson, Arizona, USA
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, USA
| | - Felicia D. Goodrum
- Department of Immunobiology, University of Arizona, Tucson, Arizona, USA
- BIO5 Institute, University of Arizona, Tucson, Arizona, USA
| | - Michael J. Imperiale
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, USA
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14
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Jones A, Zhang D, Massey SE, Deigin Y, Nemzer LR, Quay SC. Discovery of a novel merbecovirus DNA clone contaminating agricultural rice sequencing datasets from Wuhan, China. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.12.528210. [PMID: 36865340 PMCID: PMC9979991 DOI: 10.1101/2023.02.12.528210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
HKU4-related coronaviruses are a group of betacoronaviruses belonging to the same merbecovirus subgenus as Middle Eastern Respiratory Syndrome coronavirus (MERS-CoV), which causes severe respiratory illness in humans with a mortality rate of over 30%. The high genetic similarity between HKU4-related coronaviruses and MERS-CoV makes them an attractive subject of research for modeling potential zoonotic spillover scenarios. In this study, we identify a novel coronavirus contaminating agricultural rice RNA sequencing datasets from Wuhan, China. The datasets were generated by the Huazhong Agricultural University in early 2020. We were able to assemble the complete viral genome sequence, which revealed that it is a novel HKU4-related merbecovirus. The assembled genome is 98.38% identical to the closest known full genome sequence, Tylonycteris pachypus bat isolate BtTp-GX2012. Using in silico modeling, we identified that the novel HKU4-related coronavirus spike protein likely binds to human dipeptidyl peptidase 4 (DPP4), the receptor used by MERS-CoV. We further identified that the novel HKU4-related coronavirus genome has been inserted into a bacterial artificial chromosome in a format consistent with previously published coronavirus infectious clones. Additionally, we have found a near complete read coverage of the spike gene of the MERS-CoV reference strain HCoV-EMC/2012, and identify the likely presence of a HKU4-related-MERS chimera in the datasets. Our findings contribute to the knowledge of HKU4-related coronaviruses and document the use of a previously unpublished HKU4 reverse genetics system in apparent MERS-CoV related gain-of-function research. Our study also emphasizes the importance of improved biosafety protocols in sequencing centers and coronavirus research facilities.
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15
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Taha TY, Chen IP, Hayashi JM, Tabata T, Walcott K, Kimmerly GR, Syed AM, Ciling A, Suryawanshi RK, Martin HS, Bach BH, Tsou CL, Montano M, Khalid MM, Sreekumar BK, Kumar GR, Wyman S, Doudna JA, Ott M. Rapid assembly of SARS-CoV-2 genomes reveals attenuation of the Omicron BA.1 variant through NSP6. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.31.525914. [PMID: 36798416 PMCID: PMC9934579 DOI: 10.1101/2023.01.31.525914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Although the SARS-CoV-2 Omicron variant (BA.1) spread rapidly across the world and effectively evaded immune responses, its viral fitness in cell and animal models was reduced. The precise nature of this attenuation remains unknown as generating replication-competent viral genomes is challenging because of the length of the viral genome (30kb). Here, we designed a plasmid-based viral genome assembly and resc ue strategy (pGLUE) that constructs complete infectious viruses or noninfectious subgenomic replicons in a single ligation reaction with >80% efficiency. Fully sequenced replicons and infectious viral stocks can be generated in 1 and 3 weeks, respectively. By testing a series of naturally occurring viruses as well as Delta-Omicron chimeric replicons, we show that Omicron nonstructural protein 6 harbors critical attenuating mutations, which dampen viral RNA replication and reduce lipid droplet consumption. Thus, pGLUE overcomes remaining barriers to broadly study SARS-CoV-2 replication and reveals deficits in nonstructural protein function underlying Omicron attenuation.
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16
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Kurhade C, Xie X, Shi PY. Reverse genetic systems of SARS-CoV-2 for antiviral research. Antiviral Res 2023; 210:105486. [PMID: 36657881 PMCID: PMC9776485 DOI: 10.1016/j.antiviral.2022.105486] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 12/06/2022] [Accepted: 12/08/2022] [Indexed: 12/24/2022]
Abstract
Reverse genetic systems are widely used to engineer recombinant viruses with desired mutations. In response to the COVID-19 pandemic, four types of reverse genetic systems have been developed for SARS-CoV-2: (i) a full-length infectious clone that can be used to prepare recombinant SARS-CoV-2 at biosafety level 3 (BSL3), (ii) a trans-complementation system that can be used to produce single-round infectious SARS-CoV-2 at BSL2, (iii) an attenuated SARS-CoV-2 vaccine candidate (with deletions of viral accessory genes) that may be developed for veterinary use as well as for antiviral screening at BSL2, and (iv) replicon systems with deletions of viral structural genes that can be used at BSL2. Each of these genetic systems has its advantages and disadvantages that can be used to address different questions for basic and translational research. Due to the long genomic size and bacteria-toxic sequences of SARS-CoV-2, several experimental approaches have been established to rescue recombinant viruses and replicons, including (i) in vitro DNA ligation, (ii) bacterial artificial chromosome (BAC) system, (iii) yeast artificial chromosome (YAC) system, and (iv) circular polymerase extension reaction (CPER). This review summarizes the current status of SARS-CoV-2 genetic systems and their applications for studying viral replication, pathogenesis, vaccines, and therapeutics.
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Affiliation(s)
- Chaitanya Kurhade
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA
| | - Xuping Xie
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA.
| | - Pei-Yong Shi
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA; Institute for Drug Discovery, University of Texas Medical Branch, Galveston, TX, USA; Institute for Human Infection and Immunity, University of Texas Medical Branch, Galveston, TX, USA; Institute for Translational Sciences, University of Texas Medical Branch, Galveston, TX, USA; Sealy Institute for Vaccine Sciences, University of Texas Medical Branch, Galveston, TX, USA; Sealy Center for Structural Biology & Molecular Biophysics, University of Texas Medical Branch, Galveston, TX, USA.
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17
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Väisänen E, Jiang M, Laine L, Waris M, Julkunen I, Österlund P. Infectious viruses from transfected SARS-CoV-2 genomic RNA. Front Bioeng Biotechnol 2023; 11:1129111. [PMID: 37064222 PMCID: PMC10098207 DOI: 10.3389/fbioe.2023.1129111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 03/22/2023] [Indexed: 04/18/2023] Open
Abstract
SARS-CoV-2 emerged at the end of 2019, and like other novel pathogens causing severe symptoms, WHO recommended heightened biosafety measures for laboratories working with the virus. The positive-stranded genomic RNA of coronaviruses has been known to be infectious since the 1970s, and overall, all experiments with the possibility of SARS-CoV-2 propagation are carried out in higher containment level laboratories. However, as SARS-CoV-2 RNA has been routinely handled in BSL-2 laboratories, the question of the true nature of RNA infectiousness has risen along with discussion of appropriate biosafety measures. Here, we studied the ability of native SARS-CoV-2 genomic RNA to produce infectious viruses when transfected into permissive cells and discussed the biosafety control measures related to these assays. In transfection assays large quantities of genomic vRNA of SARS-CoV-2 was required for a successful production of infectious viruses. However, the quantity of vRNA alone was not the only factor, and especially when the transfected RNA was derived from infected cells, even small amounts of genomic vRNA was enough for an infection. Virus replication was found to start rapidly after transfection, and infectious viruses were detected in the cell culture media at 24 h post-transfection. In addition, silica membrane-based kits were shown to be as good as traditional TRI-reagent based methods in extracting high-quality, 30 kb-long genomic vRNA. Taken together, our data indicates that all transfection experiments with samples containing genomic SARS-CoV-2 RNA should be categorized as a propagative work and the work should be conducted only in a higher containment BSL-3 laboratory.
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Affiliation(s)
- Elina Väisänen
- Expert Microbiology Unit, Department of Health Security, Finnish Institute for Health and Welfare, Helsinki, Finland
- Infection and Immunity Unit, Institute of Biomedicine, University of Turku, Turku, Finland
- *Correspondence: Elina Väisänen,
| | - Miao Jiang
- Expert Microbiology Unit, Department of Health Security, Finnish Institute for Health and Welfare, Helsinki, Finland
- Infection and Immunity Unit, Institute of Biomedicine, University of Turku, Turku, Finland
| | - Larissa Laine
- Expert Microbiology Unit, Department of Health Security, Finnish Institute for Health and Welfare, Helsinki, Finland
| | - Matti Waris
- Infection and Immunity Unit, Institute of Biomedicine, University of Turku, Turku, Finland
| | - Ilkka Julkunen
- Infection and Immunity Unit, Institute of Biomedicine, University of Turku, Turku, Finland
| | - Pamela Österlund
- Expert Microbiology Unit, Department of Health Security, Finnish Institute for Health and Welfare, Helsinki, Finland
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18
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Advances in Molecular Genetics Enabling Studies of Highly Pathogenic RNA Viruses. Viruses 2022; 14:v14122682. [PMID: 36560685 PMCID: PMC9784166 DOI: 10.3390/v14122682] [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: 10/24/2022] [Revised: 11/25/2022] [Accepted: 11/28/2022] [Indexed: 12/05/2022] Open
Abstract
Experimental work with viruses that are highly pathogenic for humans and animals requires specialized Biosafety Level 3 or 4 facilities. Such pathogens include some spectacular but also rather seldomly studied examples such as Ebola virus (requiring BSL-4), more wide-spread and commonly studied viruses such as HIV, and the most recent example, SARS-CoV-2, which causes COVID-19. A common characteristic of these virus examples is that their genomes consist of single-stranded RNA, which requires the conversion of their genomes into a DNA copy for easy manipulation; this can be performed to study the viral life cycle in detail, develop novel therapies and vaccines, and monitor the disease course over time for chronic virus infections. We summarize the recent advances in such new genetic applications for RNA viruses in Switzerland over the last 25 years, from the early days of the HIV/AIDS epidemic to the most recent developments in research on the SARS-CoV-2 coronavirus. We highlight game-changing collaborative efforts between clinical and molecular disciplines in HIV research on the path to optimal clinical disease management. Moreover, we summarize how the modern technical evolution enabled the molecular studies of emerging RNA viruses, confirming that Switzerland is at the forefront of SARS-CoV-2 research and potentially other newly emerging viruses.
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Proteolytic Processing of the Coronavirus Replicase Nonstructural Protein 14 Exonuclease Is Not Required for Virus Replication but Alters RNA Synthesis and Viral Fitness. J Virol 2022; 96:e0084122. [PMID: 35924922 PMCID: PMC9400476 DOI: 10.1128/jvi.00841-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Coronaviruses (CoVs) initiate replication by translation of the positive-sense RNA genome into the replicase polyproteins connecting 16 nonstructural protein domains (nsp1-16), which are subsequently processed by viral proteases to yield mature nsp. For the betacoronavirus murine hepatitis virus (MHV), total inhibition of translation or proteolytic processing of replicase polyproteins results in rapid cessation of RNA synthesis. The nsp5-3CLpro (Mpro) processes nsps7-16, which assemble into functional replication-transcription complexes (RTCs), including the enzymatic nsp12-RdRp and nsp14-exoribonuclease (ExoN)/N7-methyltransferase. The nsp14-ExoN activity mediates RNA-dependent RNA proofreading, high-fidelity RNA synthesis, and replication. To date, the solved partial RTC structures, biochemistry, and models use or assume completely processed, mature nsp. Here, we demonstrate that in MHV, engineered deletion of the cleavage sites between nsp13-14 and nsp14-15 allowed recovery of replication-competent virus. Compared to wild-type (WT) MHV, the nsp13-14 and nsp14-15 cleavage deletion mutants demonstrated delayed replication kinetics, impaired genome production, altered abundance and patterns of recombination, and impaired competitive fitness. Further, the nsp13-14 and nsp14-15 mutant viruses demonstrated mutation frequencies that were significantly higher than with the WT. The results demonstrate that cleavage of nsp13-14 or nsp14-15 is not required for MHV viability and that functions of the RTC/nsp14-ExoN are impaired when assembled with noncleaved intermediates. These data will inform future genetic, structural, biochemical, and modeling studies of coronavirus RTCs and nsp 13, 14, and 15 and may reveal new approaches for inhibition or attenuation of CoV infection. IMPORTANCE Coronavirus replication requires proteolytic maturation of the nonstructural replicase proteins to form the replication-transcription complex. Coronavirus replication-transcription complex models assume mature subunits; however, mechanisms of coronavirus maturation and replicase complex formation have yet to be defined. Here, we show that for the coronavirus murine hepatitis virus, cleavage between the nonstructural replicase proteins nsp13-14 and nsp14-15 is not required for replication but does alter RNA synthesis and recombination. These results shed new light on the requirements for coronavirus maturation and replication-transcription complex assembly, and they may reveal novel therapeutic targets and strategies for attenuation.
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Stevens LJ, Pruijssers AJ, Lee HW, Gordon CJ, Tchesnokov EP, Gribble J, George AS, Hughes TM, Lu X, Li J, Perry JK, Porter DP, Cihlar T, Sheahan TP, Baric RS, Götte M, Denison MR. Mutations in the SARS-CoV-2 RNA-dependent RNA polymerase confer resistance to remdesivir by distinct mechanisms. Sci Transl Med 2022; 14:eabo0718. [PMID: 35482820 PMCID: PMC9097878 DOI: 10.1126/scitranslmed.abo0718] [Citation(s) in RCA: 104] [Impact Index Per Article: 52.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 04/14/2022] [Indexed: 12/19/2022]
Abstract
The nucleoside analog remdesivir (RDV) is a Food and Drug Administration-approved antiviral for treatment of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. Thus, it is critical to understand factors that promote or prevent RDV resistance. We passaged SARS-CoV-2 in the presence of increasing concentrations of GS-441524, the parent nucleoside of RDV. After 13 passages, we isolated three viral lineages with phenotypic resistance as defined by increases in half-maximal effective concentration from 2.7- to 10.4-fold. Sequence analysis identified nonsynonymous mutations in nonstructural protein 12 RNA-dependent RNA polymerase (nsp12-RdRp): V166A, N198S, S759A, V792I, and C799F/R. Two lineages encoded the S759A substitution at the RdRp Ser759-Asp-Asp active motif. In one lineage, the V792I substitution emerged first and then combined with S759A. Introduction of S759A and V792I substitutions at homologous nsp12 positions in murine hepatitis virus demonstrated transferability across betacoronaviruses; introduction of these substitutions resulted in up to 38-fold RDV resistance and a replication defect. Biochemical analysis of SARS-CoV-2 RdRp encoding S759A demonstrated a roughly 10-fold decreased preference for RDV-triphosphate (RDV-TP) as a substrate, whereas nsp12-V792I diminished the uridine triphosphate concentration needed to overcome template-dependent inhibition associated with RDV. The in vitro-selected substitutions identified in this study were rare or not detected in the greater than 6 million publicly available nsp12-RdRp consensus sequences in the absence of RDV selection. The results define genetic and biochemical pathways to RDV resistance and emphasize the need for additional studies to define the potential for emergence of these or other RDV resistance mutations in clinical settings.
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Affiliation(s)
- Laura J. Stevens
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Andrea J. Pruijssers
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Nashville, TN, 37232, USA
| | - Hery W. Lee
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, T6G 2T9, CA
| | - Calvin J. Gordon
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, T6G 2T9, CA
| | - Egor P. Tchesnokov
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, T6G 2T9, CA
| | - Jennifer Gribble
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Amelia S. George
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Tia M. Hughes
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Xiaotao Lu
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Jiani Li
- Gilead Sciences, Inc, Foster City, CA, 94404, USA
| | | | | | - Tomas Cihlar
- Gilead Sciences, Inc, Foster City, CA, 94404, USA
| | - Timothy P. Sheahan
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Ralph S. Baric
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Matthias Götte
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, T6G 2T9, CA
| | - Mark R. Denison
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Nashville, TN, 37232, USA
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
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21
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Abstract
Background: Knowledge about the origin of SARS-CoV-2 is necessary for both a biological and epidemiological understanding of the COVID-19 pandemic. Evidence suggests that a proximal evolutionary ancestor of SARS-CoV-2 belongs to the bat coronavirus family. However, as further evidence for a direct zoonosis remains limited, alternative modes of SARS-CoV-2 biogenesis should also be considered. Results: Here we show that the genomes of SARS-CoV-2 and SARS-CoV-1 significantly diverge from other SARS-like coronaviruses through short chromosomal sequences from the yeast S. cerevisiae at focal positions that are known to be critical for host cell invasion, virus replication, and host immune response. For SARS-CoV-1, we identify two sites: one at the start of the RNA dependent RNA polymerase gene, and the other at the start of the spike protein’s receptor binding domain; for SARS-CoV-2, one at the start of the viral replicase domain, and the other toward the end of the spike gene past its domain junction. At this junction, we detect a highly specific stretch of yeast origin covering the critical furin cleavage site insert PRRA, which has not been seen in other lineage b betacoronaviruses. As yeast is not a natural host for this virus family, we propose an artificial synthesis model for viral constructs in yeast cells based on co-transformation of virus DNA plasmids carrying yeast selectable genetic markers followed by intra-chromosomal homologous recombination through gene conversion. Highly differential yeast sequence patterns congruent with chromosomes harboring specific auxotrophic markers further support yeast artificial synthesis. Conclusions: These results provide evidence that the genomes of SARS-CoV-1 and SARS-CoV-2 contain sequence information that points to their artificial synthesis in genetically modified yeast cells. Our data specifically allow the identification of the yeast S. cerevisiae as a potential recombination donor for the critical furin cleavage site in SARS-CoV-2.
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22
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Wang W, Peng X, Jin Y, Pan JA, Guo D. Reverse genetics systems for SARS-CoV-2. J Med Virol 2022; 94:3017-3031. [PMID: 35324008 PMCID: PMC9088479 DOI: 10.1002/jmv.27738] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Accepted: 03/18/2022] [Indexed: 11/29/2022]
Abstract
The ongoing pandemic of coronavirus disease 2019 (COVID‐19) has caused severe public health crises and heavy economic losses. Limited knowledge about this deadly virus impairs our capacity to set up a toolkit against it. Thus, more studies on severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) biology are urgently needed. Reverse genetics systems, including viral infectious clones and replicons, are powerful platforms for viral research projects, spanning many aspects such as the rescues of wild‐type or mutant viral particles, the investigation of viral replication mechanism, the characterization of viral protein functions, and the studies on viral pathogenesis and antiviral drug development. The operations on viral infectious clones are strictly limited in the Biosafety Level 3 (BSL3) facilities, which are insufficient, especially during the pandemic. In contrast, the operation on the noninfectious replicon can be performed in Biosafety Level 2 (BSL2) facilities, which are widely available. After the outbreak of COVID‐19, many reverse genetics systems for SARS‐CoV‐2, including infectious clones and replicons are developed and given plenty of options for researchers to pick up according to the requirement of their research works. In this review, we summarize the available reverse genetics systems for SARS‐CoV‐2, by highlighting the features of these systems, and provide a quick guide for researchers, especially those without ample experience in operating viral reverse genetics systems.
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Affiliation(s)
- Wenhao Wang
- The Center for Infection and Immunity Study and Molecular Cancer Research Center, School of Medicine, Shenzhen Campus of Sun Yat-sen University, No. 66, Gongchang Road, Guangming District, Shenzhen, Guangdong, 518107, China
| | - Xiaoxue Peng
- The Center for Infection and Immunity Study and Molecular Cancer Research Center, School of Medicine, Shenzhen Campus of Sun Yat-sen University, No. 66, Gongchang Road, Guangming District, Shenzhen, Guangdong, 518107, China
| | - Yunyun Jin
- The Center for Infection and Immunity Study and Molecular Cancer Research Center, School of Medicine, Shenzhen Campus of Sun Yat-sen University, No. 66, Gongchang Road, Guangming District, Shenzhen, Guangdong, 518107, China
| | - Ji-An Pan
- The Center for Infection and Immunity Study and Molecular Cancer Research Center, School of Medicine, Shenzhen Campus of Sun Yat-sen University, No. 66, Gongchang Road, Guangming District, Shenzhen, Guangdong, 518107, China
| | - Deyin Guo
- The Center for Infection and Immunity Study and Molecular Cancer Research Center, School of Medicine, Shenzhen Campus of Sun Yat-sen University, No. 66, Gongchang Road, Guangming District, Shenzhen, Guangdong, 518107, China
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23
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Morales Vasquez D, Chiem K, Ye C, Martinez-Sobrido L. Bioluminescent and Fluorescent Reporter-Expressing Recombinant SARS-CoV-2. Methods Mol Biol 2022; 2524:235-248. [PMID: 35821476 DOI: 10.1007/978-1-0716-2453-1_18] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Reporter-expressing recombinant severe acute respiratory syndrome coronavirus 2 (rSARS-CoV-2) represents an excellent tool to understand the biology of and ease studying viral infections in vitro and in vivo. The broad range of applications of reporter-expressing recombinant viruses is due to the facilitated expression of fluorescence or bioluminescence readouts. In this chapter, we describe a detailed protocol on the generation of rSARS-CoV-2 expressing Venus, mCherry, and NLuc that represents a valid surrogate to track viral infections.
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Affiliation(s)
| | - Kevin Chiem
- Texas Biomedical Research Institute, San Antonio, TX, USA
| | - Chengjin Ye
- Texas Biomedical Research Institute, San Antonio, TX, USA
| | - Luis Martinez-Sobrido
- Texas Biomedical Research Institute, San Antonio, TX, USA.
- Department of Disease Prevention and Intervention, Texas Biomedical Research Institute, San Antonio, TX, USA.
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24
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Lindenbach BD. Reinventing positive-strand RNA virus reverse genetics. Adv Virus Res 2022; 112:1-29. [PMID: 35840179 PMCID: PMC9273853 DOI: 10.1016/bs.aivir.2022.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
Reverse genetics is the prospective analysis of how genotype determines phenotype. In a typical experiment, a researcher alters a viral genome, then observes the phenotypic outcome. Among RNA viruses, this approach was first applied to positive-strand RNA viruses in the mid-1970s and over nearly 50 years has become a powerful and widely used approach for dissecting the mechanisms of viral replication and pathogenesis. During this time the global health importance of two virus groups, flaviviruses (genus Flavivirus, family Flaviviridae) and betacoronaviruses (genus Betacoronavirus, subfamily Orthocoronavirinae, family Coronaviridae), have dramatically increased, yet these viruses have genomes that are technically challenging to manipulate. As a result, several new techniques have been developed to overcome these challenges. Here I briefly review key historical aspects of positive-strand RNA virus reverse genetics, describe some recent reverse genetic innovations, particularly as applied to flaviviruses and coronaviruses, and discuss their benefits and limitations within the larger context of rigorous genetic analysis.
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25
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Puhl AC, Gomes GF, Damasceno S, Fritch EJ, Levi JA, Johnson NJ, Scholle F, Premkumar L, Hurst BL, LeeMontiel F, Veras FP, Batah SS, Fabro AT, Moorman NJ, Yount BL, Dickmander R, Baric R, Pearce KH, Cunha FQ, Alves-Filho JC, Cunha TM, Ekins S. Vandetanib Reduces Inflammatory Cytokines and Ameliorates COVID-19 in Infected Mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2021:2021.12.16.472155. [PMID: 34981062 PMCID: PMC8722599 DOI: 10.1101/2021.12.16.472155] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The portfolio of SARS-CoV-2 small molecule drugs is currently limited to a handful that are either approved (remdesivir), emergency approved (dexamethasone, baricitinib) or in advanced clinical trials. We have tested 45 FDA-approved kinase inhibitors in vitro against murine hepatitis virus (MHV) as a model of SARS-CoV-2 replication and identified 12 showing inhibition in the delayed brain tumor (DBT) cell line. Vandetanib, which targets the vascular endothelial growth factor receptor (VEGFR), the epidermal growth factor receptor (EGFR), and the RET-tyrosine kinase showed the most promising results on inhibition versus toxic effect on SARS-CoV-2-infected Caco-2 and A549-hACE2 cells (IC50 0.79 μM) while also showing a reduction of > 3 log TCID50/mL for HCoV-229E. The in vivo efficacy of vandetanib was assessed in a mouse model of SARS-CoV-2 infection and statistically significantly reduced the levels of IL-6, IL-10, TNF-α, and mitigated inflammatory cell infiltrates in the lungs of infected animals but did not reduce viral load. Vandetanib rescued the decreased IFN-1β caused by SARS-CoV-2 infection in mice to levels similar to that in uninfected animals. Our results indicate that the FDA-approved vandetanib is a potential therapeutic candidate for COVID-19 positioned for follow up in clinical trials either alone or in combination with other drugs to address the cytokine storm associated with this viral infection.
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Affiliation(s)
- Ana C. Puhl
- Collaborations Pharmaceuticals, Inc., 840 Main Campus Drive, Lab 3510, Raleigh, NC 27606, USA
| | - Giovanni F. Gomes
- Center for Research in Inflammatory Diseases (CRID), Ribeirao Preto Medical School, University of Sao Paulo, Avenida Bandeirantes, 3900, Ribeirao Preto, 14049-900 ; Sao Paulo, Brazil
| | - Samara Damasceno
- Center for Research in Inflammatory Diseases (CRID), Ribeirao Preto Medical School, University of Sao Paulo, Avenida Bandeirantes, 3900, Ribeirao Preto, 14049-900 ; Sao Paulo, Brazil
| | - Ethan J. Fritch
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill NC 27599, USA
| | - James A. Levi
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA
| | - Nicole J. Johnson
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA
| | - Frank Scholle
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA
| | - Lakshmanane Premkumar
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill NC 27599, USA
| | - Brett L. Hurst
- Institute for Antiviral Research, Utah State University, Logan, UT, USA
- Department of Animal, Dairy and Veterinary Sciences, Utah State University, Logan, UT, USA
| | - Felipe LeeMontiel
- PhenoVista Biosciences, 6195 Cornerstone Ct E. #114 San Diego CA 92121
| | - Flavio P. Veras
- Center for Research in Inflammatory Diseases (CRID), Ribeirao Preto Medical School, University of Sao Paulo, Avenida Bandeirantes, 3900, Ribeirao Preto, 14049-900 ; Sao Paulo, Brazil
| | - Sabrina S. Batah
- Department of Pathology and Legal Medicine, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Alexandre T. Fabro
- Department of Pathology and Legal Medicine, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Nathaniel J. Moorman
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill NC 27599, USA
- Rapidly Emerging Antiviral Drug Discovery Initiative, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Center for Integrative Chemical Biology and Drug Discovery, Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599, USA
| | - Boyd L. Yount
- Department of Epidemiology, Gillings School of Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Rebekah Dickmander
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill NC 27599, USA
- Rapidly Emerging Antiviral Drug Discovery Initiative, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Center for Integrative Chemical Biology and Drug Discovery, Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599, USA
| | - Ralph Baric
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill NC 27599, USA
- Rapidly Emerging Antiviral Drug Discovery Initiative, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Department of Epidemiology, Gillings School of Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Kenneth H. Pearce
- Center for Integrative Chemical Biology and Drug Discovery, Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599, USA
- UNC Lineberger Comprehensive Cancer Center, Chapel Hill, North Carolina 27599, USA
| | - Fernando Q. Cunha
- Center for Research in Inflammatory Diseases (CRID), Ribeirao Preto Medical School, University of Sao Paulo, Avenida Bandeirantes, 3900, Ribeirao Preto, 14049-900 ; Sao Paulo, Brazil
| | - José C. Alves-Filho
- Center for Research in Inflammatory Diseases (CRID), Ribeirao Preto Medical School, University of Sao Paulo, Avenida Bandeirantes, 3900, Ribeirao Preto, 14049-900 ; Sao Paulo, Brazil
| | - Thiago M. Cunha
- Center for Research in Inflammatory Diseases (CRID), Ribeirao Preto Medical School, University of Sao Paulo, Avenida Bandeirantes, 3900, Ribeirao Preto, 14049-900 ; Sao Paulo, Brazil
| | - Sean Ekins
- Collaborations Pharmaceuticals, Inc., 840 Main Campus Drive, Lab 3510, Raleigh, NC 27606, USA
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Koetzner CA, Hurst-Hess KR, Kuo L, Masters PS. Analysis of a crucial interaction between the coronavirus nucleocapsid protein and the major membrane-bound subunit of the viral replicase-transcriptase complex. Virology 2021; 567:1-14. [PMID: 34933176 PMCID: PMC8669624 DOI: 10.1016/j.virol.2021.12.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 12/10/2021] [Accepted: 12/12/2021] [Indexed: 12/27/2022]
Abstract
The coronavirus nucleocapsid (N) protein comprises two RNA-binding domains connected by a central spacer, which contains a serine- and arginine-rich (SR) region. The SR region engages the largest subunit of the viral replicase-transcriptase, nonstructural protein 3 (nsp3), in an interaction that is essential for efficient initiation of infection by genomic RNA. We carried out an extensive genetic analysis of the SR region of the N protein of mouse hepatitis virus in order to more precisely define its role in RNA synthesis. We further examined the N-nsp3 interaction through construction of nsp3 mutants and by creation of an interspecies N protein chimera. Our results indicate a role for the central spacer as an interaction hub of the N molecule that is partially regulated by phosphorylation. These findings are discussed in relation to the recent discovery that nsp3 forms a molecular pore in the double-membrane vesicles that sequester the coronavirus replicase-transcriptase.
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Affiliation(s)
- Cheri A Koetzner
- Laboratory of Viral Replication and Vector Biology, Wadsworth Center, New York State Department of Health, Slingerlands, NY, 12159, USA
| | - Kelley R Hurst-Hess
- Laboratory of Viral Replication and Vector Biology, Wadsworth Center, New York State Department of Health, Slingerlands, NY, 12159, USA
| | - Lili Kuo
- Laboratory of Viral Replication and Vector Biology, Wadsworth Center, New York State Department of Health, Slingerlands, NY, 12159, USA
| | - Paul S Masters
- Laboratory of Viral Replication and Vector Biology, Wadsworth Center, New York State Department of Health, Slingerlands, NY, 12159, USA; Department of Biomedical Sciences, School of Public Health, State University of New York, Albany, NY, 12208, USA.
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27
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Abstract
Historically part of the coronavirus (CoV) family, torovirus (ToV) was recently classified into the new family Tobaniviridae. While reverse genetics systems have been established for various CoVs, none exist for ToVs. Herein, we developed a reverse genetics system using an infectious full-length cDNA clone of bovine ToV (BToV) in a bacterial artificial chromosome (BAC). Recombinant BToV harboring genetic markers had the same phenotype as wild-type (wt) BToV. To generate two types of recombinant virus, the hemagglutinin-esterase (HE) gene was edited, as cell-adapted wtBToV generally loses full-length HE (HEf), resulting in soluble HE (HEs). First, recombinant viruses with HEf and HA-tagged HEf or HEs genes were rescued. These exhibited no significant differences in their effect on virus growth in HRT18 cells, suggesting that HE is not essential for viral replication in these cells. Thereafter, we generated recombinant virus (rEGFP), wherein HE was replaced by the enhanced green fluorescent protein (EGFP) gene. The rEGFP expressed EGFP in infected cells, but showed significantly lower viral growth compared to wtBToV. Moreover, the rEGFP readily deleted the EGFP gene after one passage. Interestingly, rEGFP variants with two mutations (C1442F and I3562T) in non-structural proteins (NSPs) that emerged during passages exhibited improved EGFP expression, EGFP gene retention, and viral replication. An rEGFP into which both mutations were introduced displayed a similar phenotype to these variants, suggesting that the mutations contributed to EGFP gene acceptance. The current findings provide new insights into BToV, and reverse genetics will help advance the current understanding of this neglected pathogen. Importance ToVs are diarrhea-causing pathogens detected in various species, including humans. Through the development of a BAC-based BToV, we introduced the first reverse genetics system for Tobaniviridae. Utilizing this system, recombinant BToVs with a full-length HE gene were generated. Remarkably, although clinical BToVs generally lose the HE gene after a few passages, some recombinant viruses generated in the current study retained the HE gene for up to 20 passages while accumulating mutations in NSPs, which suggested that these mutations may be involved in HE gene retention. The EGFP gene of recombinant viruses was unstable, but rEGFP into which two NSP mutations were introduced exhibited improved EGFP expression, gene retention, and viral replication. These data suggested the existence of an NSP-based acceptance or retention mechanism for exogenous RNA or HE genes. Recombinant BToVs and reverse genetics are powerful tools for understanding fundamental viral processes, infection pathogenesis, and BToV vaccine development.
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28
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Saadi F, Pal D, Sarma JD. Spike Glycoprotein Is Central to Coronavirus Pathogenesis-Parallel Between m-CoV and SARS-CoV-2. Ann Neurosci 2021; 28:201-218. [PMID: 35341224 PMCID: PMC8948335 DOI: 10.1177/09727531211023755] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Accepted: 03/24/2021] [Indexed: 01/04/2023] Open
Abstract
Coronaviruses (CoVs) are single-stranded, polyadenylated, enveloped RNA of positive polarity with a unique potential to alter host tropism. This has been exceptionally demonstrated by the emergence of deadly virus outbreaks of the past: Severe Acute Respiratory Syndrome (SARS-CoV) in 2003 and Middle East Respiratory Syndrome (MERS-CoV) in 2012. The 2019 outbreak by the new cross-species transmission of SARS-CoV-2 has put the world on alert. CoV infection is triggered by receptor recognition, membrane fusion, and successive viral entry mediated by the surface Spike (S) glycoprotein. S protein is one of the major antigenic determinants and the target for neutralizing antibodies. It is a valuable target in antiviral therapies because of its central role in cell-cell fusion, viral antigen spread, and host immune responses leading to immunopathogenesis. The receptor-binding domain of S protein has received greater attention as it initiates host attachment and contains major antigenic determinants. However, investigating the therapeutic potential of fusion peptide as a part of the fusion core complex assembled by the heptad repeats 1 and 2 (HR1 and HR2) is also warranted. Along with receptor attachment and entry, fusion mechanisms should also be explored for designing inhibitors as a therapeutic intervention. In this article, we review the S protein function and its role in mediating membrane fusion, spread, tropism, and its associated pathogenesis with notable therapeutic strategies focusing on results obtained from studies on a murine β-Coronavirus (m-CoV) and its associated disease process.
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Affiliation(s)
- Fareeha Saadi
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Kolkata, West Bengal, India
| | - Debnath Pal
- Department of Computational and Data Sciences, Indian Institute of Science, Bengaluru, Karnataka, India
| | - Jayasri Das Sarma
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Kolkata, West Bengal, India
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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Construction of a Recombinant Porcine Epidemic Diarrhea Virus Encoding Nanoluciferase for High-Throughput Screening of Natural Antiviral Products. Viruses 2021; 13:v13091866. [PMID: 34578449 PMCID: PMC8473292 DOI: 10.3390/v13091866] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 09/09/2021] [Accepted: 09/14/2021] [Indexed: 02/06/2023] Open
Abstract
Porcine epidemic diarrhea virus (PEDV) is the predominant cause of an acute, highly contagious enteric disease in neonatal piglets. There are currently no approved drugs against PEDV infection. Here, we report the development of a nanoluciferase (NLuc)-based high-throughput screening (HTS) platform to identify novel anti-PEDV compounds. We constructed a full-length cDNA clone for a cell-adapted PEDV strain YN150. Using reverse genetics, we replaced the open reading frame 3 (ORF3) in the viral genome with an NLuc gene to engineer a recombinant PEDV expressing NLuc (rPEDV-NLuc). rPEDV-NLuc produced similar plaque morphology and showed similar growth kinetics compared with the wild-type PEDV in vitro. Remarkably, the level of luciferase activity could be stably detected in rPEDV-NLuc-infected cells and exhibited a strong positive correlation with the viral titers. Given that NLuc expression represents a direct readout of PEDV replication, anti-PEDV compounds could be easily identified by quantifying the NLuc activity. Using this platform, we screened for the anti-PEDV compounds from a library of 803 natural products and identified 25 compounds that could significantly inhibit PEDV replication. Interestingly, 7 of the 25 identified compounds were natural antioxidants, including Betulonic acid, Ursonic acid, esculetin, lithocholic acid, nordihydroguaiaretic acid, caffeic acid phenethyl ester, and grape seed extract. As expected, all of the antioxidants could potently reduce PEDV-induced oxygen species production, which, in turn, inhibit PEDV replication in a dose-dependent manner. Collectively, our findings provide a powerful platform for the rapid screening of promising therapeutic compounds against PEDV infection.
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30
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Huber T, Goldman O, Epstein AE, Stella G, Sakmar TP. Principles and practice for SARS-CoV-2 decontamination of N95 masks with UV-C. Biophys J 2021; 120:2927-2942. [PMID: 33675766 PMCID: PMC7929787 DOI: 10.1016/j.bpj.2021.02.039] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 02/22/2021] [Accepted: 02/23/2021] [Indexed: 11/02/2022] Open
Abstract
A mainstay of personal protective equipment during the coronavirus disease 2019 pandemic is the N95 filtering facepiece respirator. N95 respirators are commonly used to protect healthcare workers from respiratory pathogens, including the novel coronavirus severe acute respiratory syndrome coronavirus 2, and are increasingly employed by other frontline workers and the general public. Under routine circumstances, these masks are disposable, single-use items, but extended use and reuse practices have been broadly enacted to alleviate critical supply shortages during the coronavirus disease 2019 pandemic. Although extended-time single use presents a low risk of pathogen transfer, repeated donning and doffing of potentially contaminated masks presents increased risk of pathogen transfer. Therefore, efficient and safe decontamination methods for N95 masks are needed to reduce the risk of reuse and mitigate local supply shortages. Here, we review the available literature concerning use of germicidal ultraviolet-C (UV-C) light to decontaminate N95 masks. We propose a practical method for repeated point-of-use decontamination using commercially available UV-C cross-linker boxes from molecular biology laboratories to expose each side of the mask to 800-1200 mJ/cm2 of UV-C. We measure the dose that penetrated to the interior of the respirators and model the potential germicidal action on coronaviruses. Our experimental results, in combination with modeled data, suggest that such a UV-C treatment cycle should induce a >3-log-order reduction in viral bioburden on the surface of the respirators and a 2-log-order reduction throughout the interior. We find that a dose 50-fold greater does not impair filtration or fit of 3M 8210 N95 masks, indicating that decontamination can be performed repeatedly. As such, UV-C germicidal irradiation is a practical strategy for small-scale point-of-use decontamination of N95s.
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Affiliation(s)
- Thomas Huber
- Laboratory of Chemical Biology and Signal Transduction, Tri-Institutional Program in Chemical Biology, The Rockefeller University, New York, New York.
| | - Olivia Goldman
- Laboratory of Neurogenetics and Behavior, The Rockefeller University, New York, New York
| | - Alexander E Epstein
- David Rockefeller Graduate Program, The Rockefeller University, New York, New York
| | - Gianna Stella
- Tri-Institutional Program in Chemical Biology, The Rockefeller University, New York, New York
| | - Thomas P Sakmar
- Laboratory of Chemical Biology and Signal Transduction, Tri-Institutional Program in Chemical Biology, The Rockefeller University, New York, New York.
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31
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Puhl AC, Fritch EJ, Lane TR, Tse LV, Yount BL, Sacramento CQ, Fintelman-Rodrigues N, Tavella TA, Maranhão Costa FT, Weston S, Logue J, Frieman M, Premkumar L, Pearce KH, Hurst BL, Andrade CH, Levi JA, Johnson NJ, Kisthardt SC, Scholle F, Souza TML, Moorman NJ, Baric RS, Madrid PB, Ekins S. Repurposing the Ebola and Marburg Virus Inhibitors Tilorone, Quinacrine, and Pyronaridine: In Vitro Activity against SARS-CoV-2 and Potential Mechanisms. ACS OMEGA 2021; 6:7454-7468. [PMID: 33778258 PMCID: PMC7992063 DOI: 10.1021/acsomega.0c05996] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 03/02/2021] [Indexed: 05/11/2023]
Abstract
Severe acute respiratory coronavirus 2 (SARS-CoV-2) is a newly identified virus that has resulted in over 2.5 million deaths globally and over 116 million cases globally in March, 2021. Small-molecule inhibitors that reverse disease severity have proven difficult to discover. One of the key approaches that has been widely applied in an effort to speed up the translation of drugs is drug repurposing. A few drugs have shown in vitro activity against Ebola viruses and demonstrated activity against SARS-CoV-2 in vivo. Most notably, the RNA polymerase targeting remdesivir demonstrated activity in vitro and efficacy in the early stage of the disease in humans. Testing other small-molecule drugs that are active against Ebola viruses (EBOVs) would appear a reasonable strategy to evaluate their potential for SARS-CoV-2. We have previously repurposed pyronaridine, tilorone, and quinacrine (from malaria, influenza, and antiprotozoal uses, respectively) as inhibitors of Ebola and Marburg viruses in vitro in HeLa cells and mouse-adapted EBOV in mice in vivo. We have now tested these three drugs in various cell lines (VeroE6, Vero76, Caco-2, Calu-3, A549-ACE2, HUH-7, and monocytes) infected with SARS-CoV-2 as well as other viruses (including MHV and HCoV 229E). The compilation of these results indicated considerable variability in antiviral activity observed across cell lines. We found that tilorone and pyronaridine inhibited the virus replication in A549-ACE2 cells with IC50 values of 180 nM and IC50 198 nM, respectively. We used microscale thermophoresis to test the binding of these molecules to the spike protein, and tilorone and pyronaridine bind to the spike receptor binding domain protein with K d values of 339 and 647 nM, respectively. Human Cmax for pyronaridine and quinacrine is greater than the IC50 observed in A549-ACE2 cells. We also provide novel insights into the mechanism of these compounds which is likely lysosomotropic.
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Affiliation(s)
- Ana C. Puhl
- Collaborations
Pharmaceuticals, Inc., 840 Main Campus Drive, Lab 3510, Raleigh, North Carolina 27606, United States
| | - Ethan J. Fritch
- Department
of Microbiology and Immunology, University
of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, United States
| | - Thomas R. Lane
- Collaborations
Pharmaceuticals, Inc., 840 Main Campus Drive, Lab 3510, Raleigh, North Carolina 27606, United States
| | - Longping V. Tse
- Department
of Epidemiology, University of North Carolina
School of Medicine, Chapel Hill, North Carolina 27599, United States
| | - Boyd L. Yount
- Department
of Epidemiology, University of North Carolina
School of Medicine, Chapel Hill, North Carolina 27599, United States
| | - Carolina Q. Sacramento
- Laboratório
de Imunofarmacologia, Instituto Oswaldo Cruz (IOC), Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro, RJ 21040-900, Brazil
- Centro
De Desenvolvimento Tecnológico Em Saúde (CDTS), Fiocruz, Rio de
Janeiro 21040-900, Brazil
| | - Natalia Fintelman-Rodrigues
- Laboratório
de Imunofarmacologia, Instituto Oswaldo Cruz (IOC), Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro, RJ 21040-900, Brazil
- Centro
De Desenvolvimento Tecnológico Em Saúde (CDTS), Fiocruz, Rio de
Janeiro 21040-900, Brazil
| | - Tatyana Almeida Tavella
- Laboratory
of Tropical Diseases—Prof. Dr. Luiz Jacinto da Silva, Department
of Genetics, Evolution, Microbiology and Immunology, University of Campinas-UNICAMP, Campinas, São Paulo 13083-970, Brazil
| | - Fabio Trindade Maranhão Costa
- Laboratory
of Tropical Diseases—Prof. Dr. Luiz Jacinto da Silva, Department
of Genetics, Evolution, Microbiology and Immunology, University of Campinas-UNICAMP, Campinas, São Paulo 13083-970, Brazil
| | - Stuart Weston
- Department
of Microbiology and Immunology, University
of Maryland School of Medicine, Baltimore, Maryland 21201, United States
| | - James Logue
- Department
of Microbiology and Immunology, University
of Maryland School of Medicine, Baltimore, Maryland 21201, United States
| | - Matthew Frieman
- Department
of Microbiology and Immunology, University
of Maryland School of Medicine, Baltimore, Maryland 21201, United States
| | - Lakshmanane Premkumar
- Department
of Microbiology and Immunology, University
of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, United States
| | - Kenneth H. Pearce
- Center
for Integrative Chemical Biology and Drug Discovery, Chemical Biology
and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599, United States
- UNC
Lineberger Comprehensive Cancer Center, Chapel Hill, North Carolina 27599, United States
| | - Brett L. Hurst
- Institute
for Antiviral Research, Utah State University, Logan, Utah 84322, United States
- Department of Animal, Dairy and Veterinary Sciences, Utah State University, Logan, Utah 84322, United States
| | - Carolina Horta Andrade
- Laboratory
of Tropical Diseases—Prof. Dr. Luiz Jacinto da Silva, Department
of Genetics, Evolution, Microbiology and Immunology, University of Campinas-UNICAMP, Campinas, São Paulo 13083-970, Brazil
- LabMol—Laboratory of Molecular Modeling
and Drug Design, Faculdade
de Farmácia, Universidade Federal
de Goiás, Goiânia,
GO 74605-170, Brazil
| | - James A. Levi
- Department of Biological Sciences, North
Carolina State University, Raleigh, North Carolina 27695, United States
| | - Nicole J. Johnson
- Department of Biological Sciences, North
Carolina State University, Raleigh, North Carolina 27695, United States
| | - Samantha C. Kisthardt
- Department of Biological Sciences, North
Carolina State University, Raleigh, North Carolina 27695, United States
| | - Frank Scholle
- Department of Biological Sciences, North
Carolina State University, Raleigh, North Carolina 27695, United States
| | - Thiago Moreno L. Souza
- Laboratório
de Imunofarmacologia, Instituto Oswaldo Cruz (IOC), Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro, RJ 21040-900, Brazil
- Centro
De Desenvolvimento Tecnológico Em Saúde (CDTS), Fiocruz, Rio de
Janeiro 21040-900, Brazil
| | - Nathaniel John Moorman
- Department
of Microbiology and Immunology, University
of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, United States
- Center
for Integrative Chemical Biology and Drug Discovery, Chemical Biology
and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599, United States
- Rapidly Emerging Antiviral Drug Discovery
Initiative, University of North Carolina
at Chapel Hill, Chapel
Hill, North Carolina 27599, United States
| | - Ralph S. Baric
- Department
of Microbiology and Immunology, University
of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, United States
- Department
of Epidemiology, University of North Carolina
School of Medicine, Chapel Hill, North Carolina 27599, United States
- Rapidly Emerging Antiviral Drug Discovery
Initiative, University of North Carolina
at Chapel Hill, Chapel
Hill, North Carolina 27599, United States
| | - Peter B. Madrid
- SRI International, 333 Ravenswood Avenue, Menlo Park, California 94025, United States
| | - Sean Ekins
- Collaborations
Pharmaceuticals, Inc., 840 Main Campus Drive, Lab 3510, Raleigh, North Carolina 27606, United States
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32
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Pasin F. Oligonucleotide abundance biases aid design of a type IIS synthetic genomics framework with plant virome capacity. Biotechnol J 2021; 16:e2000354. [PMID: 33410597 DOI: 10.1002/biot.202000354] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 12/23/2020] [Accepted: 12/29/2020] [Indexed: 12/23/2022]
Abstract
Synthetic genomics-driven dematerialization of genetic resources facilitates flexible hypothesis testing and rapid product development. Biological sequences have compositional biases, which, I reasoned, could be exploited for engineering of enhanced synthetic genomics systems. In proof-of-concept assays reported herein, the abundance of random oligonucleotides in viral genomic components was analyzed and used for the rational design of a synthetic genomics framework with plant virome capacity (SynViP). Type IIS endonucleases with low abundance in the plant virome, as well as Golden Gate and No See'm principles were combined with DNA chemical synthesis for seamless viral clone assembly by one-step digestion-ligation. The framework described does not require subcloning steps, is insensitive to insert terminal sequences, and was used with linear and circular DNA molecules. Based on a digital template, DNA fragments were chemically synthesized and assembled by one-step cloning to yield a scar-free infectious clone of a plant virus suitable for Agrobacterium-mediated delivery. SynViP allowed rescue of a genuine virus without biological material, and has the potential to greatly accelerate biological characterization and engineering of plant viruses as well as derived biotechnological tools. Finally, computational identification of compositional biases in biological sequences might become a common standard to aid scalable biosystems design and engineering.
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Affiliation(s)
- Fabio Pasin
- School of Science, University of Padova, Padova, Italy.,Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan
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33
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Xie X, Lokugamage KG, Zhang X, Vu MN, Muruato AE, Menachery VD, Shi PY. Engineering SARS-CoV-2 using a reverse genetic system. Nat Protoc 2021; 16:1761-1784. [PMID: 33514944 DOI: 10.1038/s41596-021-00491-8] [Citation(s) in RCA: 104] [Impact Index Per Article: 34.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 01/04/2021] [Indexed: 12/12/2022]
Abstract
Reverse genetic systems are a critical tool for studying viruses and identifying countermeasures. In response to the ongoing COVID-19 pandemic, we recently developed an infectious complementary DNA (cDNA) clone for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The reverse genetic system can be used to rapidly engineer viruses with desired mutations to study the virus in vitro and in vivo. Viruses can also be designed for live-attenuated vaccine development and engineered with reporter genes to facilitate serodiagnosis, vaccine evaluation and antiviral screening. Thus, the reverse genetic system of SARS-CoV-2 will be widely used for both basic and translational research. However, due to the large size of the coronavirus genome (~30,000 nucleotides long) and several toxic genomic elements, manipulation of the reverse genetic system of SARS-COV-2 is not a trivial task and requires sophisticated methods. Here, we describe the technical details of how to engineer recombinant SARS-CoV-2. Overall, the process includes six steps: (i) prepare seven plasmids containing SARS-CoV-2 cDNA fragment(s), (ii) prepare high-quality DNA fragments through restriction enzyme digestion of the seven plasmids, (iii) assemble the seven cDNA fragments into a genome-length cDNA, (iv) in vitro transcribe RNA from the genome-length cDNA, (iv) electroporate the genome-length RNA into cells to recover recombinant viruses and (vi) characterize the rescued viruses. This protocol will enable researchers from different research backgrounds to master the use of the reverse genetic system and, consequently, accelerate COVID-19 research.
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Affiliation(s)
- Xuping Xie
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA
| | - Kumari G Lokugamage
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Xianwen Zhang
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA
| | - Michelle N Vu
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Antonio E Muruato
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA.,Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Vineet D Menachery
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA. .,Institute for Human Infection and Immunity, University of Texas Medical Branch, Galveston, TX, USA. .,Center for Biodefense & Emerging Infectious Diseases, University of Texas Medical Branch, Galveston, TX, USA.
| | - Pei-Yong Shi
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA. .,Institute for Human Infection and Immunity, University of Texas Medical Branch, Galveston, TX, USA. .,Sealy Institute for Vaccine Sciences, University of Texas Medical Branch, Galveston, TX, USA. .,Sealy Center for Structural Biology & Molecular Biophysics, University of Texas Medical Branch, Galveston, TX, USA. .,Department of Pharmacology & Toxicology, University of Texas Medical Branch, Galveston, TX, USA.
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34
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Luo Y, Yu F, Zhou M, Liu Y, Xia B, Zhang X, Liu J, Zhang J, Du Y, Li R, Wu L, Zhang X, Pan T, Guo D, Peng T, Zhang H. Engineering a Reliable and Convenient SARS-CoV-2 Replicon System for Analysis of Viral RNA Synthesis and Screening of Antiviral Inhibitors. mBio 2021; 12:e02754-20. [PMID: 33468688 PMCID: PMC7845634 DOI: 10.1128/mbio.02754-20] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Accepted: 12/14/2020] [Indexed: 01/18/2023] Open
Abstract
The etiologic agent of COVID-19 is highly contagious and has caused a severe global pandemic. Until now, there has been no simple and reliable system available in a lower-biosafety-grade laboratory for SARS-CoV-2 virologic research and inhibitor screening. In this study, we reported a replicon system which consists of four plasmids expressing the required segments of SARS-CoV-2. Our study revealed that the features for viral RNA synthesis and responses to antivirus drugs of the replicon are similar to those of wild-type viruses. Further analysis indicated that ORF6 provided potent in trans stimulation of the viral replication. Some viral variations, such as 5'UTR-C241T and ORF8-(T28144C) L84S mutation, also exhibit their different impact upon viral replication. Besides, the screening of clinically used drugs identified that several tyrosine kinase inhibitors and DNA-Top II inhibitors potently inhibit the replicon, as well as authentic SARS-CoV-2 viruses. Collectively, this replicon system provides a biosafety-worry-free platform for studying SARS-CoV-2 virology, monitoring the functional impact of viral mutations, and developing viral inhibitors.IMPORTANCE COVID-19 has caused a severe global pandemic. Until now, there has been no simple and reliable system available in a lower-biosafety-grade laboratory for SARS-CoV-2 virologic research and inhibitor screening. We reported a replicon system which consists of four ordinary plasmids expressing the required segments of SARS-CoV-2. Using the replicon system, we developed three application scenarios: (i) to identify the effects of viral proteins on virus replication, (ii) to identify the effects of mutations on viral replication during viral epidemics, and (iii) to perform high-throughput screening of antiviral drugs. Collectively, this replicon system would be useful for virologists to study SARS-CoV-2 virology, for epidemiologists to monitor virus mutations, and for industry to develop antiviral drugs.
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Affiliation(s)
- Yuewen Luo
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
- School of Medicine, Sun Yat-sen University, Guangzhou/Shenzhen, China
| | - Fei Yu
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China
| | - Mo Zhou
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Yang Liu
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Baijin Xia
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Xiantao Zhang
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Jun Liu
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Junsong Zhang
- Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China
| | - Yingying Du
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
- Sino-French Hoffmann Institute, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Rong Li
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Liyang Wu
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Xu Zhang
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Ting Pan
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
- School of Medicine, Sun Yat-sen University, Guangzhou/Shenzhen, China
| | - Deyin Guo
- School of Medicine, Sun Yat-sen University, Guangzhou/Shenzhen, China
| | - Tao Peng
- Sino-French Hoffmann Institute, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Hui Zhang
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
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35
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Gribble J, Stevens LJ, Agostini ML, Anderson-Daniels J, Chappell JD, Lu X, Pruijssers AJ, Routh AL, Denison MR. The coronavirus proofreading exoribonuclease mediates extensive viral recombination. PLoS Pathog 2021; 17:e1009226. [PMID: 33465137 PMCID: PMC7846108 DOI: 10.1371/journal.ppat.1009226] [Citation(s) in RCA: 156] [Impact Index Per Article: 52.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 01/29/2021] [Accepted: 12/08/2020] [Indexed: 12/14/2022] Open
Abstract
Recombination is proposed to be critical for coronavirus (CoV) diversity and emergence of SARS-CoV-2 and other zoonotic CoVs. While RNA recombination is required during normal CoV replication, the mechanisms and determinants of CoV recombination are not known. CoVs encode an RNA proofreading exoribonuclease (nsp14-ExoN) that is distinct from the CoV polymerase and is responsible for high-fidelity RNA synthesis, resistance to nucleoside analogues, immune evasion, and virulence. Here, we demonstrate that CoVs, including SARS-CoV-2, MERS-CoV, and the model CoV murine hepatitis virus (MHV), generate extensive and diverse recombination products during replication in culture. We show that the MHV nsp14-ExoN is required for native recombination, and that inactivation of ExoN results in decreased recombination frequency and altered recombination products. These results add yet another critical function to nsp14-ExoN, highlight the uniqueness of the evolved coronavirus replicase, and further emphasize nsp14-ExoN as a central, completely conserved, and vulnerable target for inhibitors and attenuation of SARS-CoV-2 and future emerging zoonotic CoVs.
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Affiliation(s)
- Jennifer Gribble
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- Vanderbilt Institute for Infection, Immunology, and Inflammation (VI4), Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Laura J. Stevens
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Maria L. Agostini
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Jordan Anderson-Daniels
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - James D. Chappell
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Xiaotao Lu
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Andrea J. Pruijssers
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Andrew L. Routh
- Department of Biochemistry and Molecular Biology, University of Texas–Medical Branch, Galveston, Texas, United States of America
- Sealy Center for Structural Biology and Molecular Biophysics, University of Texas–Medical Branch, Galveston, Texas, United States of America
| | - Mark R. Denison
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- Vanderbilt Institute for Infection, Immunology, and Inflammation (VI4), Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
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36
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Segreto R, Deigin Y, McCairn K, Sousa A, Sirotkin D, Sirotkin K, Couey JJ, Jones A, Zhang D. Should we discount the laboratory origin of COVID-19? ENVIRONMENTAL CHEMISTRY LETTERS 2021; 19:2743-2757. [PMID: 33786037 PMCID: PMC7993900 DOI: 10.1007/s10311-021-01211-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Affiliation(s)
- Rossana Segreto
- Department of Microbiology, University of Innsbruck, Innsbruck, Austria
| | | | | | - Alejandro Sousa
- Regional Hospital of Monforte, Lugo, Spain
- University of Santiago de Compostela, Santiago, Spain
| | | | | | | | - Adrian Jones
- Independent Bioinformatics Researcher, Melbourne, Australia
| | - Daoyu Zhang
- Independent Genetics Researcher, Sydney, Australia
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37
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Heer CD, Sanderson DJ, Voth LS, Alhammad YMO, Schmidt MS, Trammell SAJ, Perlman S, Cohen MS, Fehr AR, Brenner C. Coronavirus infection and PARP expression dysregulate the NAD metabolome: An actionable component of innate immunity. J Biol Chem 2020; 295:17986-17996. [PMID: 33051211 PMCID: PMC7834058 DOI: 10.1074/jbc.ra120.015138] [Citation(s) in RCA: 124] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 09/30/2020] [Indexed: 11/17/2022] Open
Abstract
Poly(ADP-ribose) polymerase (PARP) superfamily members covalently link either a single ADP-ribose (ADPR) or a chain of ADPR units to proteins using NAD as the source of ADPR. Although the well-known poly(ADP-ribosylating) (PARylating) PARPs primarily function in the DNA damage response, many noncanonical mono(ADP-ribosylating) (MARylating) PARPs are associated with cellular antiviral responses. We recently demonstrated robust up-regulation of several PARPs following infection with murine hepatitis virus (MHV), a model coronavirus. Here we show that SARS-CoV-2 infection strikingly up-regulates MARylating PARPs and induces the expression of genes encoding enzymes for salvage NAD synthesis from nicotinamide (NAM) and nicotinamide riboside (NR), while down-regulating other NAD biosynthetic pathways. We show that overexpression of PARP10 is sufficient to depress cellular NAD and that the activities of the transcriptionally induced enzymes PARP7, PARP10, PARP12 and PARP14 are limited by cellular NAD and can be enhanced by pharmacological activation of NAD synthesis. We further demonstrate that infection with MHV induces a severe attack on host cell NAD+ and NADP+ Finally, we show that NAMPT activation, NAM, and NR dramatically decrease the replication of an MHV that is sensitive to PARP activity. These data suggest that the antiviral activities of noncanonical PARP isozyme activities are limited by the availability of NAD and that nutritional and pharmacological interventions to enhance NAD levels may boost innate immunity to coronaviruses.
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Affiliation(s)
- Collin D Heer
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA; Department of Biochemistry, University of Iowa, Iowa City, Iowa, USA
| | - Daniel J Sanderson
- Department of Chemical Physiology & Biochemistry, Oregon Health Sciences University, Portland, Oregon, USA
| | - Lynden S Voth
- Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas, USA
| | - Yousef M O Alhammad
- Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas, USA
| | - Mark S Schmidt
- Department of Biochemistry, University of Iowa, Iowa City, Iowa, USA
| | | | - Stanley Perlman
- Department of Microbiology & Immunology, University of Iowa, Iowa City, Iowa, USA
| | - Michael S Cohen
- Department of Chemical Physiology & Biochemistry, Oregon Health Sciences University, Portland, Oregon, USA
| | - Anthony R Fehr
- Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas, USA.
| | - Charles Brenner
- Department of Biochemistry, University of Iowa, Iowa City, Iowa, USA.
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Puhl AC, Fritch EJ, Lane TR, Tse LV, Yount BL, Sacramento CQ, Tavella TA, Costa FTM, Weston S, Logue J, Frieman M, Premkumar L, Pearce KH, Hurst BL, Andrade CH, Levi JA, Johnson NJ, Kisthardt SC, Scholle F, Souza TML, Moorman NJ, Baric RS, Madrid P, Ekins S. Repurposing the Ebola and Marburg Virus Inhibitors Tilorone, Quinacrine and Pyronaridine: In vitro Activity Against SARS-CoV-2 and Potential Mechanisms. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2020:2020.12.01.407361. [PMID: 33299990 PMCID: PMC7724658 DOI: 10.1101/2020.12.01.407361] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
SARS-CoV-2 is a newly identified virus that has resulted in over 1.3 M deaths globally and over 59 M cases globally to date. Small molecule inhibitors that reverse disease severity have proven difficult to discover. One of the key approaches that has been widely applied in an effort to speed up the translation of drugs is drug repurposing. A few drugs have shown in vitro activity against Ebola virus and demonstrated activity against SARS-CoV-2 in vivo . Most notably the RNA polymerase targeting remdesivir demonstrated activity in vitro and efficacy in the early stage of the disease in humans. Testing other small molecule drugs that are active against Ebola virus would seem a reasonable strategy to evaluate their potential for SARS-CoV-2. We have previously repurposed pyronaridine, tilorone and quinacrine (from malaria, influenza, and antiprotozoal uses, respectively) as inhibitors of Ebola and Marburg virus in vitro in HeLa cells and of mouse adapted Ebola virus in mouse in vivo . We have now tested these three drugs in various cell lines (VeroE6, Vero76, Caco-2, Calu-3, A549-ACE2, HUH-7 and monocytes) infected with SARS-CoV-2 as well as other viruses (including MHV and HCoV 229E). The compilation of these results indicated considerable variability in antiviral activity observed across cell lines. We found that tilorone and pyronaridine inhibited the virus replication in A549-ACE2 cells with IC 50 values of 180 nM and IC 50 198 nM, respectively. We have also tested them in a pseudovirus assay and used microscale thermophoresis to test the binding of these molecules to the spike protein. They bind to spike RBD protein with K d values of 339 nM and 647 nM, respectively. Human C max for pyronaridine and quinacrine is greater than the IC 50 hence justifying in vivo evaluation. We also provide novel insights into their mechanism which is likely lysosomotropic.
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Affiliation(s)
- Ana C. Puhl
- Collaborations Pharmaceuticals, Inc., 840 Main Campus Drive, Lab 3510, Raleigh, NC 27606, USA
| | - Ethan James Fritch
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill NC 27599, USA
| | - Thomas R. Lane
- Collaborations Pharmaceuticals, Inc., 840 Main Campus Drive, Lab 3510, Raleigh, NC 27606, USA
| | - Longping V. Tse
- Department of Epidemiology, University of North Carolina School of Medicine, Chapel Hill NC 27599, USA
| | - Boyd L. Yount
- Department of Epidemiology, University of North Carolina School of Medicine, Chapel Hill NC 27599, USA
| | - Carol Queiroz Sacramento
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz (IOC), Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro, RJ, Brazil
- Centro De Desenvolvimento Tecnológico Em Saúde (CDTS), Fiocruz, Rio de Janeiro, Brasil
| | - Tatyana Almeida Tavella
- Laboratory of Tropical Diseases - Prof. Dr. Luiz Jacinto da Silva, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas-UNICAMP, Campinas, SP, Brazil
| | - Fabio Trindade Maranhão Costa
- Laboratory of Tropical Diseases - Prof. Dr. Luiz Jacinto da Silva, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas-UNICAMP, Campinas, SP, Brazil
| | - Stuart Weston
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - James Logue
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Matthew Frieman
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Lakshmanane Premkumar
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill NC 27599, USA
| | - Kenneth H. Pearce
- Center for Integrative Chemical Biology and Drug Discovery, Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599, USA
- UNC Lineberger Comprehensive Cancer Center, Chapel Hill, North Carolina 27599, USA
| | - Brett L. Hurst
- Institute for Antiviral Research, Utah State University, Logan, UT, USA
- Department of Animal, Dairy and Veterinary Sciences, Utah State University, Logan, UT, USA
| | - Carolina Horta Andrade
- Laboratory of Tropical Diseases - Prof. Dr. Luiz Jacinto da Silva, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas-UNICAMP, Campinas, SP, Brazil
- LabMol - Laboratory of Molecular Modeling and Drug Design, Faculdade de Farmácia, Universidade Federal de Goiás, Goiânia, GO, 74605-170, Brazil
| | - James A. Levi
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA
| | - Nicole J. Johnson
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA
| | - Samantha C. Kisthardt
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA
| | - Frank Scholle
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA
| | - Thiago Moreno L. Souza
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz (IOC), Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro, RJ, Brazil
- Centro De Desenvolvimento Tecnológico Em Saúde (CDTS), Fiocruz, Rio de Janeiro, Brasil
| | - Nathaniel John Moorman
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill NC 27599, USA
- Center for Integrative Chemical Biology and Drug Discovery, Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599, USA
- Rapidly Emerging Antiviral Drug Discovery Initiative, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Ralph S. Baric
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill NC 27599, USA
- Department of Epidemiology, University of North Carolina School of Medicine, Chapel Hill NC 27599, USA
- Rapidly Emerging Antiviral Drug Discovery Initiative, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Peter Madrid
- SRI International, 333 Ravenswood Avenue, Menlo Park, CA 94025, USA
| | - Sean Ekins
- Collaborations Pharmaceuticals, Inc., 840 Main Campus Drive, Lab 3510, Raleigh, NC 27606, USA
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Deng X, Buckley AC, Pillatzki A, Lager KM, Baker SC, Faaberg KS. Development and utilization of an infectious clone for porcine deltacoronavirus strain USA/IL/2014/026. Virology 2020; 553:35-45. [PMID: 33220618 PMCID: PMC7664480 DOI: 10.1016/j.virol.2020.11.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 11/09/2020] [Accepted: 11/10/2020] [Indexed: 01/17/2023]
Abstract
We report the generation of a full-length infectious cDNA clone for porcine deltacoronavirus strain USA/IL/2014/026. Similar to the parental strain, the infectious clone virus (icPDCoV) replicated efficiently in cell culture and caused mild clinical symptoms in piglets. To investigate putative viral interferon (IFN) antagonists, we generated two mutant viruses: a nonstructural protein 15 mutant virus that encodes a catalytically-inactive endoribonuclease (icEnUmut), and an accessory gene NS6-deletion virus in which the NS6 gene was replaced with the mNeonGreen sequence (icDelNS6/nG). By infecting PK1 cells with these recombinant PDCoVs, we found that icDelNS6/nG elicited similar levels of type I IFN responses as icPDCoV, however icEnUmut stimulated robust type I IFN responses, demonstrating that the deltacoronavirus endoribonuclease, but not NS6, functions as an IFN antagonist in PK1 cells. Collectively, the construction of a full-length infectious clone and the identification of an IFN-antagonistic endoribonuclease will aid in the development of live-attenuated deltacoronavirus vaccines.
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Affiliation(s)
- Xufang Deng
- Department of Microbiology and Immunology, Loyola University Chicago, Stritch School of Medicine, Maywood, IL, 60153, USA.
| | - Alexandra C Buckley
- Virus and Prion Research Unit, USDA-ARS-National Animal Disease Center, Ames, IA, 50010, USA
| | - Angela Pillatzki
- Animal Disease Research & Diagnostic Laboratory, South Dakota State University, Brookings, SD, 57007, USA
| | - Kelly M Lager
- Virus and Prion Research Unit, USDA-ARS-National Animal Disease Center, Ames, IA, 50010, USA
| | - Susan C Baker
- Department of Microbiology and Immunology, Loyola University Chicago, Stritch School of Medicine, Maywood, IL, 60153, USA
| | - Kay S Faaberg
- Virus and Prion Research Unit, USDA-ARS-National Animal Disease Center, Ames, IA, 50010, USA.
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Edwards CE, Yount BL, Graham RL, Leist SR, Hou YJ, Dinnon KH, Sims AC, Swanstrom J, Gully K, Scobey TD, Cooley MR, Currie CG, Randell SH, Baric RS. Swine acute diarrhea syndrome coronavirus replication in primary human cells reveals potential susceptibility to infection. Proc Natl Acad Sci U S A 2020; 117:26915-26925. [PMID: 33046644 PMCID: PMC7604506 DOI: 10.1073/pnas.2001046117] [Citation(s) in RCA: 102] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Zoonotic coronaviruses represent an ongoing threat, yet the myriads of circulating animal viruses complicate the identification of higher-risk isolates that threaten human health. Swine acute diarrhea syndrome coronavirus (SADS-CoV) is a newly discovered, highly pathogenic virus that likely evolved from closely related HKU2 bat coronaviruses, circulating in Rhinolophus spp. bats in China and elsewhere. As coronaviruses cause severe economic losses in the pork industry and swine are key intermediate hosts of human disease outbreaks, we synthetically resurrected a recombinant virus (rSADS-CoV) as well as a derivative encoding tomato red fluorescent protein (tRFP) in place of ORF3. rSADS-CoV replicated efficiently in a variety of continuous animal and primate cell lines, including human liver and rectal carcinoma cell lines. Of concern, rSADS-CoV also replicated efficiently in several different primary human lung cell types, as well as primary human intestinal cells. rSADS-CoV did not use human coronavirus ACE-2, DPP4, or CD13 receptors for docking and entry. Contemporary human donor sera neutralized the group I human coronavirus NL63, but not rSADS-CoV, suggesting limited human group I coronavirus cross protective herd immunity. Importantly, remdesivir, a broad-spectrum nucleoside analog that is effective against other group 1 and 2 coronaviruses, efficiently blocked rSADS-CoV replication in vitro. rSADS-CoV demonstrated little, if any, replicative capacity in either immune-competent or immunodeficient mice, indicating a critical need for improved animal models. Efficient growth in primary human lung and intestinal cells implicate SADS-CoV as a potential higher-risk emerging coronavirus pathogen that could negatively impact the global economy and human health.
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Affiliation(s)
- Caitlin E Edwards
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Boyd L Yount
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Rachel L Graham
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Sarah R Leist
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Yixuan J Hou
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Kenneth H Dinnon
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Amy C Sims
- Chemical and Biological Signatures Division, Pacific Northwest National Laboratory, Richland, WA 99354
| | - Jesica Swanstrom
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Kendra Gully
- Department of Comparative Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Trevor D Scobey
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Michelle R Cooley
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Caroline G Currie
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Scott H Randell
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Ralph S Baric
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599;
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
- Rapidly Emerging Antiviral Drug Discovery Initiative, University of North Carolina, Chapel Hill, NC 27599
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41
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Heer CD, Sanderson DJ, Voth LS, Alhammad YM, Schmidt MS, Trammell SA, Perlman S, Cohen MS, Fehr AR, Brenner C. Coronavirus infection and PARP expression dysregulate the NAD Metabolome: an actionable component of innate immunity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2020:2020.04.17.047480. [PMID: 32511303 PMCID: PMC7217258 DOI: 10.1101/2020.04.17.047480] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Poly-ADP-ribose polymerase (PARP) superfamily members covalently link either a single ADP-ribose (ADPR) or a chain of ADPR units to proteins using nicotinamide adenine dinucleotide (NAD) as the source of ADPR. While the well-known poly-ADP-ribosylating (PARylating) PARPs primarily function in the DNA damage response, many non-canonical mono-ADP-ribosylating (MARylating) PARPs are associated with cellular antiviral responses. We recently demonstrated robust upregulation of several PARPs following infection with Murine Hepatitis Virus (MHV), a model coronavirus. Here we show that SARS-CoV-2 infection strikingly upregulates MARylating PARPs and induces the expression of genes encoding enzymes for salvage NAD synthesis from nicotinamide (NAM) and nicotinamide riboside (NR), while downregulating other NAD biosynthetic pathways. We show that overexpression of PARP10 is sufficient to depress cellular NAD and that the activities of the transcriptionally induced enzymes PARP7, PARP10, PARP12 and PARP14 are limited by cellular NAD and can be enhanced by pharmacological activation of NAD synthesis. We further demonstrate that infection with MHV induces a severe attack on host cell NAD+ and NADP+. Finally, we show that NAMPT activation, NAM and NR dramatically decrease the replication of an MHV virus that is sensitive to PARP activity. These data suggest that the antiviral activities of noncanonical PARP isozyme activities are limited by the availability of NAD, and that nutritional and pharmacological interventions to enhance NAD levels may boost innate immunity to coronaviruses.
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Affiliation(s)
- Collin D. Heer
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, IA, USA
- Department of Biochemistry, University of Iowa, Iowa City, IA, USA
| | - Daniel J. Sanderson
- Department of Chemical Physiology & Biochemistry, Oregon Health Sciences University, Portland, OR, USA
| | - Lynden S. Voth
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS, USA
| | | | - Mark S. Schmidt
- Department of Biochemistry, University of Iowa, Iowa City, IA, USA
| | | | - Stanley Perlman
- Department of Microbiology & Immunology, University of Iowa, Iowa City, IA, USA
| | - Michael S. Cohen
- Department of Chemical Physiology & Biochemistry, Oregon Health Sciences University, Portland, OR, USA
| | - Anthony R. Fehr
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS, USA
| | - Charles Brenner
- Department of Biochemistry, University of Iowa, Iowa City, IA, USA
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Sirotkin K, Sirotkin D. Might SARS-CoV-2 Have Arisen via Serial Passage through an Animal Host or Cell Culture?: A potential explanation for much of the novel coronavirus' distinctive genome. Bioessays 2020; 42:e2000091. [PMID: 32786014 PMCID: PMC7435492 DOI: 10.1002/bies.202000091] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 07/13/2020] [Indexed: 12/16/2022]
Abstract
Despite claims from prominent scientists that SARS-CoV-2 indubitably emerged naturally, the etiology of this novel coronavirus remains a pressing and open question: Without knowing the true nature of a disease, it is impossible for clinicians to appropriately shape their care, for policy-makers to correctly gauge the nature and extent of the threat, and for the public to appropriately modify their behavior. Unless the intermediate host necessary for completing a natural zoonotic jump is identified, the dual-use gain-of-function research practice of viral serial passage should be considered a viable route by which the novel coronavirus arose. The practice of serial passage mimics a natural zoonotic jump, and offers explanations for SARS-CoV-2's distinctive spike-protein region and its unexpectedly high affinity for angiotensin converting enzyme (ACE2), as well as the notable polybasic furin cleavage site within it. Additional molecular clues raise further questions, all of which warrant full investigation into the novel coronavirus's origins and a re-examination of the risks and rewards of dual-use gain-of-function research.
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Affiliation(s)
- Karl Sirotkin
- Karl Sirotkin LLC, 1301 Tadsworth TerraceLake MaryFL32746USA
| | - Dan Sirotkin
- Karl Sirotkin LLC, 1301 Tadsworth TerraceLake MaryFL32746USA
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43
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Fehr AR. Bacterial Artificial Chromosome-Based Lambda Red Recombination with the I-SceI Homing Endonuclease for Genetic Alteration of MERS-CoV. Methods Mol Biol 2020; 2099:53-68. [PMID: 31883087 PMCID: PMC7121842 DOI: 10.1007/978-1-0716-0211-9_5] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Over the past two decades, several coronavirus (CoV) infectious clones have been engineered, allowing for the manipulation of their large viral genomes (~30 kb) using unique reverse genetic systems. These reverse genetic systems include targeted recombination, in vitro ligation, vaccinia virus vectors, and bacterial artificial chromosomes (BACs). Quickly after the identification of Middle East respiratory syndrome-CoV (MERS-CoV), both in vitro ligation and BAC-based reverse genetic technologies were engineered for MERS-CoV to study its basic biological properties, develop live-attenuated vaccines, and test antiviral drugs. Here, I will describe how lambda red recombination can be used with the MERS-CoV BAC to quickly and efficiently introduce virtually any type of genetic modification (point mutations, insertions, deletions) into the MERS-CoV genome and recover recombinant virus.
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Affiliation(s)
- Anthony R Fehr
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS, USA.
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Koma T, Adachi S, Doi N, Adachi A, Nomaguchi M. Toward Understanding Molecular Bases for Biological Diversification of Human Coronaviruses: Present Status and Future Perspectives. Front Microbiol 2020; 11:2016. [PMID: 32983025 PMCID: PMC7477919 DOI: 10.3389/fmicb.2020.02016] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 07/30/2020] [Indexed: 12/11/2022] Open
Abstract
Human coronaviruses (HCoVs) are of zoonotic origins, and seven distinct HCoVs are currently known to infect humans. While the four seasonal HCoVs appear to be mildly pathogenic and circulate among human populations, the other three designated SARS-CoV, MERS-CoV, and SARS-CoV-2 can cause severe diseases in some cases. The newly identified SARS-CoV-2, a causative virus of COVID-19 that can be deadly, is now spreading worldwide much more efficiently than the other two pathogenic viruses. Despite evident differences in these properties, all HCoVs commonly have an exceptionally large genomic RNA with a rather peculiar gene organization and have the potential to readily alter their biological properties. CoVs are characterized by their biological diversifications, high recombination, and efficient adaptive evolution. We are particularly concerned about the high replication and transmission nature of SARS-CoV-2, which may lead to the emergence of more transmissible and/or pathogenic viruses than ever before. Furthermore, novel variant viruses may appear at any time from the CoV pools actively circulating or persistently being maintained in the animal reservoirs, and from the CoVs in infected human individuals. In this review, we describe knowns of the CoVs and then mention their unknowns to clarify the major issues to be addressed. Genome organizations and sequences of numerous CoVs have been determined, and the viruses are presently classified into separate phylogenetic groups. Functional roles in the viral replication cycle in vitro of non-structural and structural proteins are also quite well understood or suggested. In contrast, those in the in vitro and in vivo replication for various accessory proteins encoded by the variable 3' one-third portion of the CoV genome mostly remain to be determined. Importantly, the genomic sequences/structures closely linked to the high CoV recombination are poorly investigated and elucidated. Also, determinants for adaptation and pathogenicity have not been systematically investigated. We summarize here these research situations. Among conceivable projects, we are especially interested in the underlying molecular mechanism by which the observed CoV diversification is generated. Finally, as virologists, we discuss how we handle the present difficulties and propose possible research directions in the medium or long term.
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Affiliation(s)
- Takaaki Koma
- Department of Microbiology, Tokushima University Graduate School of Medical Science, Tokushima, Japan
| | - Shun Adachi
- Department of Microbiology, Kansai Medical University, Osaka, Japan
| | - Naoya Doi
- Department of Microbiology, Tokushima University Graduate School of Medical Science, Tokushima, Japan
| | - Akio Adachi
- Department of Microbiology, Kansai Medical University, Osaka, Japan
| | - Masako Nomaguchi
- Department of Microbiology, Tokushima University Graduate School of Medical Science, Tokushima, Japan
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Abstract
Since the end of 2019, the global COVID-19 outbreak has once again made coronaviruses a hot topic. Vaccines are hoped to be an effective way to stop the spread of the virus. However, there are no clinically approved vaccines available for coronavirus infections. Reverse genetics technology can realize the operation of RNA virus genomes at the DNA level and provide new ideas and strategies for the development of new vaccines. In this review, we systematically describe the role of reverse genetics technology in studying the effects of coronavirus proteins on viral virulence and innate immunity, cell and tissue tropism and antiviral drug screening. An efficient reverse genetics platform is useful for obtaining the ideal attenuated strain to prepare an attenuated live vaccine.
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46
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Jia Q, Shi S, Yuan G, Shi J, Shi S, Hu Y. Analysis of knowledge bases and research hotspots of coronavirus from the perspective of mapping knowledge domain. Medicine (Baltimore) 2020; 99:e20378. [PMID: 32481423 DOI: 10.1097/md.0000000000020378] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Coronaviruses have drawn attention since the beginning of the 21st century. Over the past 17 years, coronaviruses have triggered several outbreaks of epidemic in people, which brought great threats to global public health security. We analyzed the publications on coronavirus with bibliometrics software and qualitatively and quantitatively evaluated the knowledge base and hot topics of coronavirus research from 2003 to 2020. METHODS We explored the publications on coronavirus in the Web of Science core collection (WOSCC) from 2003 to 2020. Bibliometric analysis, evaluating knowledge base, and research hotspots were performed based on CiteSpace V (Drexel University, Chaomei Chen). RESULTS There were a total of 8433 publications of coronavirus. The research on coronavirus boomed when a novel coronavirus triggered outbreaks in people. The leading country was the United States, and the leading institution was the University of Hong Kong. The most productive researchers were: Yuen KY, Drosten C, Baric RS. The keywords analysis showed that SARS-CoV, infection, acute respiratory syndrome, antibody, receptor, and spike protein were research hotspots. The research categories analysis showed that virology, microbiology, veterinary sciences, infectious diseases, and biochemistry and molecular biology were hot research categories. CONCLUSIONS Bibliometric analysis of the literature shows the research on coronavirus boomed when a novel coronavirus triggered outbreaks in people. With the end of the epidemic, the research tended to be cooling. Virus identification, pathogenesis, and coronavirus-mediated diseases attracted much attention. We must continue studying the viruses after an outbreak ended.
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Affiliation(s)
- Qiulei Jia
- Cardiovascular Department, Guang'anmen Hospital, China Academy of Chinese Medical Sciences
- Graduate School, Beijing University of Chinese Medicine, Beijing, China
| | - Shuqing Shi
- Cardiovascular Department, Guang'anmen Hospital, China Academy of Chinese Medical Sciences
- Graduate School, Beijing University of Chinese Medicine, Beijing, China
| | - Guozhen Yuan
- Cardiovascular Department, Guang'anmen Hospital, China Academy of Chinese Medical Sciences
| | - Jingjing Shi
- Cardiovascular Department, Guang'anmen Hospital, China Academy of Chinese Medical Sciences
| | - Shuai Shi
- Cardiovascular Department, Guang'anmen Hospital, China Academy of Chinese Medical Sciences
| | - Yuanhui Hu
- Cardiovascular Department, Guang'anmen Hospital, China Academy of Chinese Medical Sciences
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47
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Structure-Guided Mutagenesis Alters Deubiquitinating Activity and Attenuates Pathogenesis of a Murine Coronavirus. J Virol 2020; 94:JVI.01734-19. [PMID: 32188728 PMCID: PMC7269429 DOI: 10.1128/jvi.01734-19] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 03/09/2020] [Indexed: 12/25/2022] Open
Abstract
Coronaviruses employ a genetic economy by encoding multifunctional proteins that function in viral replication and also modify the host environment to disarm the innate immune response. The coronavirus papain-like protease 2 (PLP2) domain possesses protease activity, which cleaves the viral replicase polyprotein, and also DUB activity (deconjugating ubiquitin/ubiquitin-like molecules from modified substrates) using identical catalytic residues. To separate the DUB activity from the protease activity, we employed a structure-guided mutagenesis approach and identified residues that are important for ubiquitin binding. We found that mutating the ubiquitin-binding residues results in a PLP2 that has reduced DUB activity but retains protease activity. We engineered a recombinant murine coronavirus to express the DUB mutant and showed that the DUB mutant virus activated an earlier type I interferon response in macrophages and exhibited reduced replication in mice. The results of this study demonstrate that PLP2/DUB is an interferon antagonist and a virulence trait of coronaviruses. Coronaviruses express a multifunctional papain-like protease, termed papain-like protease 2 (PLP2). PLP2 acts as a protease that cleaves the viral replicase polyprotein and as a deubiquitinating (DUB) enzyme which removes ubiquitin (Ub) moieties from ubiquitin-conjugated proteins. Previous in vitro studies implicated PLP2/DUB activity as a negative regulator of the host interferon (IFN) response, but the role of DUB activity during virus infection was unknown. Here, we used X-ray structure-guided mutagenesis and functional studies to identify amino acid substitutions within the ubiquitin-binding surface of PLP2 that reduced DUB activity without affecting polyprotein processing activity. We engineered a DUB mutation (Asp1772 to Ala) into a murine coronavirus and evaluated the replication and pathogenesis of the DUB mutant virus (DUBmut) in cultured macrophages and in mice. We found that the DUBmut virus replicates similarly to the wild-type (WT) virus in cultured cells, but the DUBmut virus activates an IFN response at earlier times compared to the wild-type virus infection in macrophages, consistent with DUB activity negatively regulating the IFN response. We compared the pathogenesis of the DUBmut virus to that of the wild-type virus and found that the DUBmut-infected mice had a statistically significant reduction (P < 0.05) in viral titer in liver and spleen at day 5 postinfection (d p.i.), although both wild-type and DUBmut virus infections resulted in similar liver pathology. Overall, this study demonstrates that structure-guided mutagenesis aids the identification of critical determinants of the PLP2-ubiquitin complex and that PLP2/DUB activity plays a role as an interferon antagonist in coronavirus pathogenesis. IMPORTANCE Coronaviruses employ a genetic economy by encoding multifunctional proteins that function in viral replication and also modify the host environment to disarm the innate immune response. The coronavirus papain-like protease 2 (PLP2) domain possesses protease activity, which cleaves the viral replicase polyprotein, and also DUB activity (deconjugating ubiquitin/ubiquitin-like molecules from modified substrates) using identical catalytic residues. To separate the DUB activity from the protease activity, we employed a structure-guided mutagenesis approach and identified residues that are important for ubiquitin binding. We found that mutating the ubiquitin-binding residues results in a PLP2 that has reduced DUB activity but retains protease activity. We engineered a recombinant murine coronavirus to express the DUB mutant and showed that the DUB mutant virus activated an earlier type I interferon response in macrophages and exhibited reduced replication in mice. The results of this study demonstrate that PLP2/DUB is an interferon antagonist and a virulence trait of coronaviruses.
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Xie X, Muruato A, Lokugamage KG, Narayanan K, Zhang X, Zou J, Liu J, Schindewolf C, Bopp NE, Aguilar PV, Plante KS, Weaver SC, Makino S, LeDuc JW, Menachery VD, Shi PY. An Infectious cDNA Clone of SARS-CoV-2. Cell Host Microbe 2020; 27:841-848.e3. [PMID: 32289263 PMCID: PMC7153529 DOI: 10.1016/j.chom.2020.04.004] [Citation(s) in RCA: 504] [Impact Index Per Article: 126.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Revised: 03/30/2020] [Accepted: 04/01/2020] [Indexed: 12/11/2022]
Abstract
The ongoing pandemic of COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), underscores the urgency to develop experimental systems for studying this virus and identifying countermeasures. We report a reverse genetic system for SARS-CoV-2. Seven complimentary DNA (cDNA) fragments spanning the SARS-CoV-2 genome were assembled into a full-genome cDNA. RNA transcribed from the full-genome cDNA was highly infectious after electroporation into cells, producing 2.9 × 106 plaque-forming unit (PFU)/mL of virus. Compared with a clinical isolate, the infectious-clone-derived SARS-CoV-2 (icSARS-CoV-2) exhibited similar plaque morphology, viral RNA profile, and replication kinetics. Additionally, icSARS-CoV-2 retained engineered molecular markers and did not acquire other mutations. We generated a stable mNeonGreen SARS-CoV-2 (icSARS-CoV-2-mNG) by introducing this reporter gene into ORF7 of the viral genome. icSARS-CoV-2-mNG was successfully used to evaluate the antiviral activities of interferon (IFN). Collectively, the reverse genetic system and reporter virus provide key reagents to study SARS-CoV-2 and develop countermeasures.
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Affiliation(s)
- Xuping Xie
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA.
| | - Antonio Muruato
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA; Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Kumari G Lokugamage
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Krishna Narayanan
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Xianwen Zhang
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA
| | - Jing Zou
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA
| | - Jianying Liu
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Craig Schindewolf
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Nathen E Bopp
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA
| | - Patricia V Aguilar
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA; World Reference Center for Emerging Viruses and Arboviruses, University of Texas Medical Branch, Galveston, TX, USA; Institute for Human Infection and Immunity, University of Texas Medical Branch, Galveston, TX, USA
| | - Kenneth S Plante
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA; World Reference Center for Emerging Viruses and Arboviruses, University of Texas Medical Branch, Galveston, TX, USA
| | - Scott C Weaver
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA; World Reference Center for Emerging Viruses and Arboviruses, University of Texas Medical Branch, Galveston, TX, USA; Institute for Human Infection and Immunity, University of Texas Medical Branch, Galveston, TX, USA; Institute for Translational Sciences, University of Texas Medical Branch, Galveston, TX, USA; Department of Pathology and Center for Biodefense & Emerging Infectious Diseases, University of Texas Medical Branch, Galveston, TX, USA; Sealy Institute for Vaccine Sciences, University of Texas Medical Branch, Galveston, TX, USA
| | - Shinji Makino
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA; Institute for Human Infection and Immunity, University of Texas Medical Branch, Galveston, TX, USA; Sealy Center for Structural Biology & Molecular Biophysics, University of Texas Medical Branch, Galveston, TX, USA
| | - James W LeDuc
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA; Galveston National Laboratory, University of Texas Medical Branch, Galveston, TX, USA
| | - Vineet D Menachery
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA; Institute for Human Infection and Immunity, University of Texas Medical Branch, Galveston, TX, USA; Department of Pathology and Center for Biodefense & Emerging Infectious Diseases, University of Texas Medical Branch, Galveston, TX, USA.
| | - Pei-Yong Shi
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA; Institute for Human Infection and Immunity, University of Texas Medical Branch, Galveston, TX, USA; Sealy Institute for Vaccine Sciences, University of Texas Medical Branch, Galveston, TX, USA; Sealy Center for Structural Biology & Molecular Biophysics, University of Texas Medical Branch, Galveston, TX, USA; Department of Pharmacology & Toxicology, University of Texas Medical Branch, Galveston, TX, USA.
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Sheahan TP, Sims AC, Zhou S, Graham RL, Pruijssers AJ, Agostini ML, Leist SR, Schäfer A, Dinnon KH, Stevens LJ, Chappell JD, Lu X, Hughes TM, George AS, Hill CS, Montgomery SA, Brown AJ, Bluemling GR, Natchus MG, Saindane M, Kolykhalov AA, Painter G, Harcourt J, Tamin A, Thornburg NJ, Swanstrom R, Denison MR, Baric RS. An orally bioavailable broad-spectrum antiviral inhibits SARS-CoV-2 in human airway epithelial cell cultures and multiple coronaviruses in mice. Sci Transl Med 2020; 12:eabb5883. [PMID: 32253226 PMCID: PMC7164393 DOI: 10.1126/scitranslmed.abb5883] [Citation(s) in RCA: 749] [Impact Index Per Article: 187.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 04/03/2020] [Indexed: 12/16/2022]
Abstract
Coronaviruses (CoVs) traffic frequently between species resulting in novel disease outbreaks, most recently exemplified by the newly emerged SARS-CoV-2, the causative agent of COVID-19. Here, we show that the ribonucleoside analog β-d-N4-hydroxycytidine (NHC; EIDD-1931) has broad-spectrum antiviral activity against SARS-CoV-2, MERS-CoV, SARS-CoV, and related zoonotic group 2b or 2c bat-CoVs, as well as increased potency against a CoV bearing resistance mutations to the nucleoside analog inhibitor remdesivir. In mice infected with SARS-CoV or MERS-CoV, both prophylactic and therapeutic administration of EIDD-2801, an orally bioavailable NHC prodrug (β-d-N4-hydroxycytidine-5'-isopropyl ester), improved pulmonary function and reduced virus titer and body weight loss. Decreased MERS-CoV yields in vitro and in vivo were associated with increased transition mutation frequency in viral, but not host cell RNA, supporting a mechanism of lethal mutagenesis in CoV. The potency of NHC/EIDD-2801 against multiple CoVs and oral bioavailability highlights its potential utility as an effective antiviral against SARS-CoV-2 and other future zoonotic CoVs.
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Affiliation(s)
- Timothy P Sheahan
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
| | - Amy C Sims
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Shuntai Zhou
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Rachel L Graham
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Andrea J Pruijssers
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Maria L Agostini
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Sarah R Leist
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Alexandra Schäfer
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Kenneth H Dinnon
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Laura J Stevens
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - James D Chappell
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Xiaotao Lu
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Tia M Hughes
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Amelia S George
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Collin S Hill
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Stephanie A Montgomery
- Department of Pathology and Laboratory Medicine, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Ariane J Brown
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Gregory R Bluemling
- Emory Institute of Drug Development (EIDD), Emory University, Atlanta, GA 30322, USA
- Drug Innovation Ventures at Emory (DRIVE), Atlanta, GA 30322, USA
| | - Michael G Natchus
- Emory Institute of Drug Development (EIDD), Emory University, Atlanta, GA 30322, USA
| | - Manohar Saindane
- Emory Institute of Drug Development (EIDD), Emory University, Atlanta, GA 30322, USA
| | - Alexander A Kolykhalov
- Emory Institute of Drug Development (EIDD), Emory University, Atlanta, GA 30322, USA
- Drug Innovation Ventures at Emory (DRIVE), Atlanta, GA 30322, USA
| | - George Painter
- Emory Institute of Drug Development (EIDD), Emory University, Atlanta, GA 30322, USA
- Drug Innovation Ventures at Emory (DRIVE), Atlanta, GA 30322, USA
- Department of Pharmacology and Chemical Biology, Emory University, Atlanta, GA 30322, USA
| | - Jennifer Harcourt
- Division of Viral Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - Azaibi Tamin
- Division of Viral Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - Natalie J Thornburg
- Division of Viral Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - Ronald Swanstrom
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Mark R Denison
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Ralph S Baric
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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50
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Coronavirus endoribonuclease targets viral polyuridine sequences to evade activating host sensors. Proc Natl Acad Sci U S A 2020; 117:8094-8103. [PMID: 32198201 PMCID: PMC7149396 DOI: 10.1073/pnas.1921485117] [Citation(s) in RCA: 193] [Impact Index Per Article: 48.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Cells carry sensors that are primed to detect invading viruses. To avoid being recognized, coronaviruses express factors that interfere with host immune sensing pathways. Previous studies revealed that a coronavirus endoribonuclease (EndoU) delays activation of the host sensor system, but the mechanism was not known. Here, we report that EndoU cleaves a viral polyuridine sequence that would otherwise activate host immune sensors. This information may be used in developing inhibitors that target EndoU activity and prevent diseases caused by coronaviruses. Coronaviruses (CoVs) are positive-sense RNA viruses that can emerge from endemic reservoirs and infect zoonotically, causing significant morbidity and mortality. CoVs encode an endoribonuclease designated EndoU that facilitates evasion of host pattern recognition receptor MDA5, but the target of EndoU activity was not known. Here, we report that EndoU cleaves the 5′-polyuridines from negative-sense viral RNA, termed PUN RNA, which is the product of polyA-templated RNA synthesis. Using a virus containing an EndoU catalytic-inactive mutation, we detected a higher abundance of PUN RNA in the cytoplasm compared to wild-type−infected cells. Furthermore, we found that transfecting PUN RNA into cells stimulates a robust, MDA5-dependent interferon response, and that removal of the polyuridine extension on the RNA dampens the response. Overall, the results of this study reveal the PUN RNA to be a CoV MDA5-dependent pathogen-associated molecular pattern (PAMP). We also establish a mechanism for EndoU activity to cleave and limit the accumulation of this PAMP. Since EndoU activity is highly conserved in all CoVs, inhibiting this activity may serve as an approach for therapeutic interventions against existing and emerging CoV infections.
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