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Tawfeeq C, Song J, Khaniya U, Madej T, Wang J, Youkharibache P, Abrol R. Towards a structural and functional analysis of the immunoglobulin-fold proteome. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2024; 138:135-178. [PMID: 38220423 DOI: 10.1016/bs.apcsb.2023.11.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2024]
Abstract
The immunoglobulin fold (Ig fold) domain is a super-secondary structural motif consisting of a sandwich with two layers of β-sheets that is present in many proteins with very diverse biological functions covering a wide range of physiological processes. This domain presents a modular architecture built with β strands connected by variable length loops that has a highly conserved structural core of four β-strands and quite variable β-sheet extensions in the two sandwich layers that enable both divergent and convergent evolutionary mechanisms in the known Ig fold proteome. The central role of this Ig fold's structural plasticity in the evolutionary success of antibodies in our immune system is well established. Nature has also utilized this Ig fold in all domains of life in many different physiological contexts that go way beyond the immune system. Here we will present a structural and functional overview of the utilization of the Ig fold in different biological processes and in different cellular contexts to highlight some of the innumerable ways that this structural motif can interact in multidomain proteins to enable their diversity of functions. This includes shareable specific protein structure visualizations behind those functions that serve as starting points for further explorations of the biomolecular interactions spanning the Ig fold proteome. This overview also highlights how this Ig fold is being utilized through natural adaptation, engineering, and even building from scratch for a range of biotechnological applications.
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Affiliation(s)
- Caesar Tawfeeq
- Department of Chemistry and Biochemistry, California State University Northridge, Northridge, United States
| | - James Song
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, United States
| | - Umesh Khaniya
- Cancer Data Science Laboratory, National Cancer Institute, National Institutes of Health, Bethesda, United States
| | - Thomas Madej
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, United States
| | - Jiyao Wang
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, United States
| | - Philippe Youkharibache
- Cancer Data Science Laboratory, National Cancer Institute, National Institutes of Health, Bethesda, United States.
| | - Ravinder Abrol
- Department of Chemistry and Biochemistry, California State University Northridge, Northridge, United States.
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2
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Surya W, Queralt-Martin M, Mu Y, Aguilella VM, Torres J. SARS-CoV-2 accessory protein 7b forms homotetramers in detergent. Virol J 2022; 19:193. [PMID: 36414943 PMCID: PMC9680129 DOI: 10.1186/s12985-022-01920-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 11/04/2022] [Indexed: 11/23/2022] Open
Abstract
A global pandemic is underway caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The SARS-CoV-2 genome, like its predecessor SARS-CoV, contains open reading frames that encode accessory proteins involved in virus-host interactions active during infection and which likely contribute to pathogenesis. One of these accessory proteins is 7b, with only 44 (SARS-CoV) and 43 (SARS-CoV-2) residues. It has one predicted transmembrane domain fully conserved, which suggests a functional role, whereas most variability is contained in the predicted cytoplasmic C-terminus. In SARS-CoV, 7b protein is expressed in infected cells, and the transmembrane domain was necessary and sufficient for Golgi localization. Also, anti-p7b antibodies have been found in the sera of SARS-CoV convalescent patients. In the present study, we have investigated the hypothesis that SARS-2 7b protein forms oligomers with ion channel activity. We show that in both SARS viruses 7b is almost completely α-helical and has a single transmembrane domain. In SDS, 7b forms various oligomers, from monomers to tetramers, but only monomers when exposed to reductants. Combination of SDS gel electrophoresis and analytical ultracentrifugation (AUC) in both equilibrium and velocity modes suggests a dimer-tetramer equilibrium, but a monomer-dimer-tetramer equilibrium in the presence of reductant. This data suggests that although disulfide-linked dimers may be present, they are not essential to form tetramers. Inclusion of pentamers or higher oligomers in the SARS-2 7b model were detrimental to fit quality. Preliminary models of this association was generated with AlphaFold2, and two alternative models were exposed to a molecular dynamics simulation in presence of a model lipid membrane. However, neither of the two models provided any evident pathway for ions. To confirm this, SARS-2 p7b was studied using Planar Bilayer Electrophysiology. Addition of p7b to model membranes produced occasional membrane permeabilization, but this was not consistent with bona fide ion channels made of a tetrameric assembly of α-helices.
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Affiliation(s)
- Wahyu Surya
- grid.59025.3b0000 0001 2224 0361School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551 Singapore
| | - Maria Queralt-Martin
- grid.9612.c0000 0001 1957 9153Laboratory of Molecular Biophysics, Department of Physics, Universitat Jaume I, 12080 Castelló, Spain
| | - Yuguang Mu
- grid.59025.3b0000 0001 2224 0361School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551 Singapore
| | - Vicente M. Aguilella
- grid.9612.c0000 0001 1957 9153Laboratory of Molecular Biophysics, Department of Physics, Universitat Jaume I, 12080 Castelló, Spain
| | - Jaume Torres
- grid.59025.3b0000 0001 2224 0361School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551 Singapore
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3
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Abdullaev A, Abdurakhimov A, Mirakbarova Z, Ibragimova S, Tsoy V, Nuriddinov S, Dalimova D, Turdikulova S, Abdurakhmonov I. Genome sequence diversity of SARS-CoV-2 obtained from clinical samples in Uzbekistan. PLoS One 2022; 17:e0270314. [PMID: 35759503 PMCID: PMC9236271 DOI: 10.1371/journal.pone.0270314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 06/07/2022] [Indexed: 11/27/2022] Open
Abstract
Tracking temporal and spatial genomic changes and evolution of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are among the most urgent research topics worldwide, which help to elucidate the coronavirus disease 2019 (COVID-19) pathogenesis and the effect of deleterious variants. Our current study concentrates genetic diversity of SARS-CoV-2 variants in Uzbekistan and their associations with COVID-19 severity. Thirty-nine whole genome sequences (WGS) of SARS-CoV-2 isolated from PCR-positive patients from Tashkent, Uzbekistan for the period of July-August 2021, were generated and further subjected to further genomic analysis. Genome-wide annotations of clinical isolates from our study have revealed a total of 223 nucleotide-level variations including SNPs and 34 deletions at different positions throughout the entire genome of SARS-CoV-2. These changes included two novel mutations at the Nonstructural protein (Nsp) 13: A85P and Nsp12: Y479N, which were unreported previously. There were two groups of co-occurred substitution patterns: the missense mutations in the Spike (S): D614G, Open Reading Frame (ORF) 1b: P314L, Nsp3: F924, 5`UTR:C241T; Nsp3:P2046L and Nsp3:P2287S, and the synonymous mutations in the Nsp4:D2907 (C8986T), Nsp6:T3646A and Nsp14:A1918V regions, respectively. The “Nextstrain” clustered the largest number of SARS-CoV-2 strains into the Delta clade (n = 32; 82%), followed by two Alpha-originated (n = 4; 10,3%) and 20A (n = 3; 7,7%) clades. Geographically the Delta clade sample sequences were grouped into several clusters with the SARS-CoV genotypes from Russia, Denmark, USA, Egypt and Bangladesh. Phylogenetically, the Delta isolates in our study belong to the two main subclades 21A (56%) and 21J (44%). We found that females were more affected by 21A, whereas males by 21J variant (χ2 = 4.57; p ≤ 0.05, n = 32). The amino acid substitution ORF7a:P45L in the Delta isolates found to be significantly associated with disease severity. In conclusion, this study evidenced that Identified novel substitutions Nsp13: A85P and Nsp12: Y479N, have a destabilizing effect, while missense substitution ORF7a: P45L significantly associated with disease severity.
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Affiliation(s)
| | | | | | | | - Vladimir Tsoy
- Center for Advanced Technologies, Tashkent, Uzbekistan
| | | | | | | | - Ibrokhim Abdurakhmonov
- Center for Advanced Technologies, Tashkent, Uzbekistan
- Center of Genomics and Bioinformatics, Academy of Sciences of Uzbekistan, Qibray Region, Tashkent, Republic of Uzbekistan
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4
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Goud VR, Chakraborty R, Chakraborty A, Lavudi K, Patnaik S, Sharma S, Patnaik S. A bioinformatic approach of targeting SARS-CoV-2 replication by silencing a conserved alternative reserve of the orf8 gene using host miRNAs. Comput Biol Med 2022; 145:105436. [PMID: 35366472 PMCID: PMC8942883 DOI: 10.1016/j.compbiomed.2022.105436] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 03/11/2022] [Accepted: 03/20/2022] [Indexed: 12/16/2022]
Abstract
The causative agent of the COVID-19 pandemic, the SARS-CoV-2 virus has yielded multiple relevant mutations, many of which have branched into major variants. The Omicron variant has a huge similarity with the original viral strain (first COVID-19 strain from Wuhan). Among different genes, the highly variable orf8 gene is responsible for crucial host interactions and has undergone multiple mutations and indels. The sequence of the orf8 gene of the Omicron variant is, however, identical with the gene sequence of the wild type. orf8 modulates the host immunity making it easier for the virus to conceal itself and remain undetected. Variants seem to be deleting this gene without affecting the viral replication. While analyzing, we came across the conserved orf7a gene in the viral genome which exhibits a partial sequence homology as well as functional similarity with the SARS-CoV-2 orf8. Hence, we have proposed here in our hypothesis that, orf7a might be an alternative reserve of orf8 present in the virus which was compensating for the lost gene. A computational approach was adopted where we screened various miRNAs targeted against the orf8 gene. These miRNAs were then docked onto the orf8 mRNA sequences. The same set of miRNAs was then used to check for their binding affinity with the orf7a reference mRNA. Results showed that miRNAs targeting the orf8 had favorable shape complementarity and successfully docked with the orf7a gene as well. These findings provide a basis for developing new therapeutic approaches where both orf8 and orf7a can be targeted simultaneously.
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Affiliation(s)
| | | | | | - Kousalya Lavudi
- School of Biotechnology, KIIT University, Bhubaneswar, India
| | - Sriram Patnaik
- School of Biotechnology, KIIT University, Bhubaneswar, India
| | - Swati Sharma
- School of Biotechnology, KIIT University, Bhubaneswar, India,Dept. of Skill Buildings Shri Ramasamy Memorial University, Sikkim, Gangtok, 737102, India
| | - Srinivas Patnaik
- School of Biotechnology, KIIT University, Bhubaneswar, India,Corresponding author. School of Biotechnology, KIIT University, Bhubaneswar, 751024, India
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5
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Ongaro A, Oselladore E, Memo M, Ribaudo G, Gianoncelli A. Insight into the LFA-1/SARS-CoV-2 Orf7a Complex by Protein-Protein Docking, Molecular Dynamics, and MM-GBSA Calculations. J Chem Inf Model 2021; 61:2780-2787. [PMID: 34043356 PMCID: PMC8189040 DOI: 10.1021/acs.jcim.1c00198] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
In the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) genome, open reading frames (ORFs) encode for viral accessory proteins. Among these, Orf7a structurally resembles the members of the immunoglobulin (Ig) superfamily and intracellular adhesion molecules (ICAMs), in particular. ICAMs are involved in integrin binding through lymphocyte function-associated antigen 1 (LFA-1). Based on such considerations and on previous findings on SARS-CoV, it has been postulated that the formation of the LFA-1/Orf7a complex could contribute to SARS-CoV-2 infectivity and pathogenicity. With the current work, we aim at providing insight into this macromolecular assembly, taking advantage of the recently reported SARS-CoV-2 Orf7a structure. Protein-protein docking, molecular dynamics (MD) simulations, and a Molecular Mechanical-Generalized Born Surface Area (MM-GBSA)-based stage were enrolled to provide refined models.
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Affiliation(s)
- Alberto Ongaro
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy
| | - Erika Oselladore
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy
| | - Maurizio Memo
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy
| | - Giovanni Ribaudo
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy
| | - Alessandra Gianoncelli
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy
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6
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Durojaye OA, Okoro NO, Odiba AS. Characterization of the SARS-CoV-2 coronavirus X4-like accessory protein. EGYPTIAN JOURNAL OF MEDICAL HUMAN GENETICS 2021; 22:48. [PMID: 38624802 PMCID: PMC8105150 DOI: 10.1186/s43042-021-00160-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 03/24/2021] [Indexed: 11/10/2022] Open
Abstract
Background The novel coronavirus SARS-CoV-2 is currently a global threat to health and economies. Therapeutics and vaccines are in rapid development; however, none of these therapeutics are considered as absolute cure, and the potential to mutate makes it necessary to find therapeutics that target a highly conserved regions of the viral structure. Results In this study, we characterized an essential but poorly understood coronavirus accessory X4 protein, a core and stable component of the SARS-CoV family. Sequence analysis shows a conserved ~ 90% identity between the SARS-CoV-2 and previously characterized X4 protein in the database. QMEAN Z score of the model protein shows a value of around 0.5, within the acceptable range 0-1. A MolProbity score of 2.96 was obtained for the model protein and indicates a good quality model. The model has Ramachandran values of φ = - 57o and ψ = - 47o for α-helices and values of φ = - 130o and ψ = + 140o for twisted sheets. Conclusions The protein data obtained from this study provides robust information for further in vitro and in vivo experiment, targeted at devising therapeutics against the virus. Phylogenetic analysis further supports previous evidence that the SARS-CoV-2 is positioned with the SL-CoVZC45, BtRs-BetaCoV/YN2018B and the RS4231 Bat SARS-like corona viruses.
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Affiliation(s)
- Olanrewaju Ayodeji Durojaye
- Department of Molecular and Cell Biology, University of Science and Technology of China, Hefei, People’s Republic of China
| | - Nkwachukwu Oziamara Okoro
- Guangxi Bioscience and Technology Research Centre, Guangxi Academy of Sciences, Nanning, 530007 People’s Republic of China
- Department of Pharmaceutical and Medicinal Chemistry, Faculty of Pharmaceutical Sciences, University of Nigeria, Nsukka, 410001 Nigeria
| | - Arome Solomon Odiba
- Guangxi Bioscience and Technology Research Centre, Guangxi Academy of Sciences, Nanning, 530007 People’s Republic of China
- Department of Molecular Genetics and Biotechnology, Faculty of Biological Sciences, University of Nigeria, Nsukka, Enugu State 410001 Nigeria
- Department of Biochemistry, College of Life Science and Technology, Guangxi University, Nanning, 530007 People’s Republic of China
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7
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Zhou Z, Huang C, Zhou Z, Huang Z, Su L, Kang S, Chen X, Chen Q, He S, Rong X, Xiao F, Chen J, Chen S. Structural insight reveals SARS-CoV-2 ORF7a as an immunomodulating factor for human CD14 + monocytes. iScience 2021; 24:102187. [PMID: 33615195 PMCID: PMC7879101 DOI: 10.1016/j.isci.2021.102187] [Citation(s) in RCA: 75] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2020] [Revised: 11/11/2020] [Accepted: 02/09/2021] [Indexed: 01/08/2023] Open
Abstract
Dysregulated immune cell responses have been linked to the severity of coronavirus disease 2019 (COVID-19), but the specific viral factors of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were currently unknown. Herein, we reveal that the Immunoglobulin-like fold ectodomain of the viral protein SARS-CoV-2 ORF7a interacts with high efficiency to CD14+ monocytes in human peripheral blood, compared to pathogenic protein SARS-CoV ORF7a. The crystal structure of SARS-CoV-2 ORF7a at 2.2 Å resolution reveals three remarkable changes on the amphipathic side of the four-stranded β-sheet, implying a potential functional interface of the viral protein. Importantly, SARS-CoV-2 ORF7a coincubation with CD14+ monocytes ex vivo triggered a decrease in HLA-DR/DP/DQ expression levels and upregulated significant production of proinflammatory cytokines, including IL-6, IL-1β, IL-8, and TNF-α. Our work demonstrates that SARS-CoV-2 ORF7a is an immunomodulating factor for immune cell binding and triggers dramatic inflammatory responses, providing promising therapeutic drug targets for pandemic COVID-19.
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Affiliation(s)
- Ziliang Zhou
- Molecular Imaging Center, Guangdong Provincial Key Laboratory of Biomedical Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai 519000, China
| | - Chunliu Huang
- Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
| | - Zhechong Zhou
- Molecular Imaging Center, Guangdong Provincial Key Laboratory of Biomedical Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai 519000, China
| | - Zhaoxia Huang
- Molecular Imaging Center, Guangdong Provincial Key Laboratory of Biomedical Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai 519000, China
| | - Lili Su
- The Health Management Center, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai 519000, China
| | - Sisi Kang
- Molecular Imaging Center, Guangdong Provincial Key Laboratory of Biomedical Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai 519000, China
| | - Xiaoxue Chen
- Molecular Imaging Center, Guangdong Provincial Key Laboratory of Biomedical Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai 519000, China
| | - Qiuyue Chen
- Molecular Imaging Center, Guangdong Provincial Key Laboratory of Biomedical Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai 519000, China
| | - Suhua He
- Molecular Imaging Center, Guangdong Provincial Key Laboratory of Biomedical Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai 519000, China
| | - Xia Rong
- Institute of Clinical Transfusion, Guangzhou Blood Center, Guangzhou 510095, China
| | - Fei Xiao
- Molecular Imaging Center, Guangdong Provincial Key Laboratory of Biomedical Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai 519000, China
| | - Jun Chen
- Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
- Key Laboratory of Tropical Disease Control of the Ministry of Education, Sun Yat-sen University, Guangzhou 510080, China
- Center for Precision Medicine, Sun Yat-sen University, Guangzhou 510080, China
| | - Shoudeng Chen
- Molecular Imaging Center, Guangdong Provincial Key Laboratory of Biomedical Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai 519000, China
- Department of Experimental Medicine, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai 519000, China
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8
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Spanakis N, Kassela K, Dovrolis N, Bampali M, Gatzidou E, Kafasi A, Froukala E, Stavropoulou A, Lilakos K, Veletza S, Tsiodras S, Tsakris A, Karakasiliotis I. A main event and multiple introductions of SARS-CoV-2 initiated the COVID-19 epidemic in Greece. J Med Virol 2021; 93:2899-2907. [PMID: 33410223 DOI: 10.1002/jmv.26778] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 12/23/2020] [Accepted: 12/29/2020] [Indexed: 12/19/2022]
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel coronavirus responsible for the coronavirus disease 2019 (COVID-19) pandemic. Chains of infections starting from various countries worldwide seeded the outbreak of COVID-19 in Athens, capital city of Greece. A full-genome analysis of isolates from Athens' hospitals and other healthcare providers revealed the variety of SARS-CoV-2 that initiated the pandemic before lockdown and passenger flight restrictions. A dominant variant, encompassing the G614D amino acid substitution, spread through a major virus dispersal event, and sporadic introductions of rare variants characterized the local initiation of the epidemic. Mutations within the genome highlighted the genetic drift of the virus as rare variants emerged. An important variant contained a premature stop codon in orf7a leading to the truncation of a possibly important for viral pathogenesis domain. This study may serve as a reference for resolving future lines of infection in the area, especially after resumption of passenger flight connections to Athens and Greece during summer of 2020.
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Affiliation(s)
- Nikolaos Spanakis
- Laboratory of Microbiology, Medical School, National and Kapodistrian University, Athens, Greece
| | - Katerina Kassela
- Laboratory of Biology, Department of Medicine, Democritus University of Thrace, Alexandroupolis, Greece
| | - Nikolas Dovrolis
- Laboratory of Biology, Department of Medicine, Democritus University of Thrace, Alexandroupolis, Greece
| | - Maria Bampali
- Laboratory of Biology, Department of Medicine, Democritus University of Thrace, Alexandroupolis, Greece
| | - Elisavet Gatzidou
- Laboratory of Biology, Department of Medicine, Democritus University of Thrace, Alexandroupolis, Greece
| | - Athanasia Kafasi
- Laboratory of Microbiology, Medical School, National and Kapodistrian University, Athens, Greece
| | - Elisavet Froukala
- Laboratory of Microbiology, Medical School, National and Kapodistrian University, Athens, Greece
| | - Anastasia Stavropoulou
- Laboratory of Microbiology, Medical School, National and Kapodistrian University, Athens, Greece
| | - Konstantinos Lilakos
- ANTISEL SA and Haematology Clinic, Medical School, National and Kapodistrian University, Athens, Greece
| | - Stavroula Veletza
- Laboratory of Biology, Department of Medicine, Democritus University of Thrace, Alexandroupolis, Greece
| | - Sotirios Tsiodras
- 4th Department of Internal Medicine, Medical School, National and Kapodistrian University, Athens, Greece
| | - Athanasios Tsakris
- Laboratory of Microbiology, Medical School, National and Kapodistrian University, Athens, Greece
| | - Ioannis Karakasiliotis
- Laboratory of Biology, Department of Medicine, Democritus University of Thrace, Alexandroupolis, Greece
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9
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Giri R, Bhardwaj T, Shegane M, Gehi BR, Kumar P, Gadhave K, Oldfield CJ, Uversky VN. Understanding COVID-19 via comparative analysis of dark proteomes of SARS-CoV-2, human SARS and bat SARS-like coronaviruses. Cell Mol Life Sci 2021; 78:1655-1688. [PMID: 32712910 DOI: 10.1101/2020.03.13.990598] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 07/03/2020] [Accepted: 07/17/2020] [Indexed: 05/18/2023]
Abstract
The recently emerged coronavirus designated as SARS-CoV-2 (also known as 2019 novel coronavirus (2019-nCoV) or Wuhan coronavirus) is a causative agent of coronavirus disease 2019 (COVID-19), which is rapidly spreading throughout the world now. More than 1.21 million cases of SARS-CoV-2 infection and more than 67,000 COVID-19-associated mortalities have been reported worldwide till the writing of this article, and these numbers are increasing every passing hour. The World Health Organization (WHO) has declared the SARS-CoV-2 spread as a global public health emergency and admitted COVID-19 as a pandemic now. Multiple sequence alignment data correlated with the already published reports on SARS-CoV-2 evolution indicated that this virus is closely related to the bat severe acute respiratory syndrome-like coronavirus (bat SARS-like CoV) and the well-studied human SARS coronavirus (SARS-CoV). The disordered regions in viral proteins are associated with the viral infectivity and pathogenicity. Therefore, in this study, we have exploited a set of complementary computational approaches to examine the dark proteomes of SARS-CoV-2, bat SARS-like, and human SARS CoVs by analysing the prevalence of intrinsic disorder in their proteins. According to our findings, SARS-CoV-2 proteome contains very significant levels of structural order. In fact, except for nucleocapsid, Nsp8, and ORF6, the vast majority of SARS-CoV-2 proteins are mostly ordered proteins containing less intrinsically disordered protein regions (IDPRs). However, IDPRs found in SARS-CoV-2 proteins are functionally important. For example, cleavage sites in its replicase 1ab polyprotein are found to be highly disordered, and almost all SARS-CoV-2 proteins contains molecular recognition features (MoRFs), which are intrinsic disorder-based protein-protein interaction sites that are commonly utilized by proteins for interaction with specific partners. The results of our extensive investigation of the dark side of SARS-CoV-2 proteome will have important implications in understanding the structural and non-structural biology of SARS or SARS-like coronaviruses.
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Affiliation(s)
- Rajanish Giri
- School of Basic Sciences, Indian Institute of Technology Mandi, VPO Kamand, Mandi, Himachal Pradesh, 175005, India.
| | - Taniya Bhardwaj
- School of Basic Sciences, Indian Institute of Technology Mandi, VPO Kamand, Mandi, Himachal Pradesh, 175005, India
| | - Meenakshi Shegane
- School of Basic Sciences, Indian Institute of Technology Mandi, VPO Kamand, Mandi, Himachal Pradesh, 175005, India
| | - Bhuvaneshwari R Gehi
- School of Basic Sciences, Indian Institute of Technology Mandi, VPO Kamand, Mandi, Himachal Pradesh, 175005, India
| | - Prateek Kumar
- School of Basic Sciences, Indian Institute of Technology Mandi, VPO Kamand, Mandi, Himachal Pradesh, 175005, India
| | - Kundlik Gadhave
- School of Basic Sciences, Indian Institute of Technology Mandi, VPO Kamand, Mandi, Himachal Pradesh, 175005, India
| | | | - Vladimir N Uversky
- Department of Molecular Medicine, Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
- Laboratory of New Methods in Biology, Institute for Biological Instrumentation of the Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", Moscow region, Pushchino, 142290, Russia
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10
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Nizamudeen ZA, Xu ER, Karthik V, Halawa M, Arkill KP, Jackson AM, Bates DO, Emsley J. Structural assessment of SARS-CoV2 accessory protein ORF7a predicts LFA-1 and Mac-1 binding potential. Biosci Rep 2021; 41:BSR20203837. [PMID: 33305306 PMCID: PMC7796194 DOI: 10.1042/bsr20203837] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 12/09/2020] [Accepted: 12/10/2020] [Indexed: 01/17/2023] Open
Abstract
ORF7a is an accessory protein common to SARS-CoV1 and the recently discovered SARS-CoV2, which is causing the COVID-19 pandemic. The ORF7a protein has a structural homology with ICAM-1 which binds to the T lymphocyte integrin receptor LFA-1. As COVID-19 has a strong immune component as part of the disease, we sought to determine whether SARS-CoV2 would have a similar structural interaction with LFA-1. Using molecular docking simulations, we found that SARS-CoV2 ORF7a has the key structural determinants required to bind LFA-1 but also the related leukocyte integrin Mac-1, which is also known to be expressed by macrophages. Our study shows that SARS-CoV2 ORF7a protein has a conserved Ig immunoglobulin-like fold containing an integrin binding site that provides a mechanistic hypothesis for SARS-CoV2's interaction with the human immune system. This suggests that experimental investigation of ORF7a-mediated effects on immune cells such as T lymphocytes and macrophages (leukocytes) could help understand the disease further and develop effective treatments.
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Affiliation(s)
- Zubair Ahmed Nizamudeen
- Division of Cancer and Stem Cells, School of Medicine, Biodiscovery Institute, University of Nottingham, Nottingham NG7 2RD, U.K
| | - Emma-Ruoqi Xu
- School of Pharmacy, Biodiscovery Institute, University of Nottingham, Nottingham NG7 2RD, U.K
| | - Vivin Karthik
- Graduate School of Biomedical Sciences and Engineering, University of Maine, Orono, ME 04469, U.S.A
| | - Mohamed Halawa
- School of Pharmacy, Biodiscovery Institute, University of Nottingham, Nottingham NG7 2RD, U.K
| | - Kenton P. Arkill
- Division of Cancer and Stem Cells, School of Medicine, Biodiscovery Institute, University of Nottingham, Nottingham NG7 2RD, U.K
| | - Andrew M. Jackson
- Division of Cancer and Stem Cells, School of Medicine, Biodiscovery Institute, University of Nottingham, Nottingham NG7 2RD, U.K
| | - David O. Bates
- Division of Cancer and Stem Cells, School of Medicine, Biodiscovery Institute, University of Nottingham, Nottingham NG7 2RD, U.K
| | - Jonas Emsley
- School of Pharmacy, Biodiscovery Institute, University of Nottingham, Nottingham NG7 2RD, U.K
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11
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Panzera Y, Ramos N, Frabasile S, Calleros L, Marandino A, Tomás G, Techera C, Grecco S, Fuques E, Goñi N, Ramas V, Coppola L, Chiparelli H, Sorhouet C, Mogdasy C, Arbiza J, Delfraro A, Pérez R. A deletion in SARS-CoV-2 ORF7 identified in COVID-19 outbreak in Uruguay. Transbound Emerg Dis 2021; 68:3075-3082. [PMID: 33501730 PMCID: PMC8014828 DOI: 10.1111/tbed.14002] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 01/15/2021] [Accepted: 01/21/2021] [Indexed: 01/20/2023]
Abstract
The analysis of genetic diversity in SARS‐CoV‐2 is the focus of several studies, providing insights into how the virus emerged and evolves. Most common changes in SARS‐CoV‐2 are single or point nucleotide substitutions; meanwhile, insertions and deletions (indels) have been identified as a less frequent source of viral genetic variability. Here, we report the emergence of a 12‐nucleotide deletion in ORF7a, resulting in a 4‐amino acid in‐frame deletion. The Δ12 variant was identified in viruses from patients of a single outbreak and represents the first report of this deletion in South American isolates. Phylogenetic analysis revealed that Δ12 strains belong to the lineage B.1.1 and clustered separated from the remaining Uruguayan strains. The ∆12 variant was detected in 14 patients of this outbreak by NGS sequencing and/or two rapid and economic methodologies: Sanger amplicon sequencing and capillary electrophoresis. The presence of strong molecular markers as the deletion described here are useful for tracking outbreaks and reveal a significant aspect of the SARS‐CoV‐2 evolution on the robustness of the virus to keep its functionality regardless loss of genetic material.
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Affiliation(s)
- Yanina Panzera
- Sección Genética Evolutiva, Departamento de Biología Animal, Instituto de Biología, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Natalia Ramos
- Sección Virología. Instituto de Biología e Instituto de Química Biológica. Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Sandra Frabasile
- Sección Virología. Instituto de Biología e Instituto de Química Biológica. Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Lucía Calleros
- Sección Genética Evolutiva, Departamento de Biología Animal, Instituto de Biología, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Ana Marandino
- Sección Genética Evolutiva, Departamento de Biología Animal, Instituto de Biología, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Gonzalo Tomás
- Sección Genética Evolutiva, Departamento de Biología Animal, Instituto de Biología, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Claudia Techera
- Sección Genética Evolutiva, Departamento de Biología Animal, Instituto de Biología, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Sofía Grecco
- Sección Genética Evolutiva, Departamento de Biología Animal, Instituto de Biología, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Eddie Fuques
- Sección Genética Evolutiva, Departamento de Biología Animal, Instituto de Biología, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Natalia Goñi
- Departamento de Laboratorios de Salud Pública. Ministerio de Salud Pública, Centro Nacional de Referencia de Influenza y otros Virus Respiratorios, Montevideo, Uruguay
| | - Viviana Ramas
- Departamento de Laboratorios de Salud Pública. Ministerio de Salud Pública, Centro Nacional de Referencia de Influenza y otros Virus Respiratorios, Montevideo, Uruguay
| | - Leticia Coppola
- Departamento de Laboratorios de Salud Pública. Ministerio de Salud Pública, Centro Nacional de Referencia de Influenza y otros Virus Respiratorios, Montevideo, Uruguay
| | - Héctor Chiparelli
- Departamento de Laboratorios de Salud Pública. Ministerio de Salud Pública, Centro Nacional de Referencia de Influenza y otros Virus Respiratorios, Montevideo, Uruguay
| | - Cecilia Sorhouet
- Laboratorio de Biología Molecular, Mutualista Médica Uruguaya, Montevideo, Uruguay
| | - Cristina Mogdasy
- Departamento de Laboratorios de Salud Pública. Ministerio de Salud Pública, Centro Nacional de Referencia de Influenza y otros Virus Respiratorios, Montevideo, Uruguay
| | - Juan Arbiza
- Sección Virología. Instituto de Biología e Instituto de Química Biológica. Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Adriana Delfraro
- Sección Virología. Instituto de Biología e Instituto de Química Biológica. Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Ruben Pérez
- Sección Genética Evolutiva, Departamento de Biología Animal, Instituto de Biología, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
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12
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Neches RY, Kyrpides NC, Ouzounis CA. Atypical Divergence of SARS-CoV-2 Orf8 from Orf7a within the Coronavirus Lineage Suggests Potential Stealthy Viral Strategies in Immune Evasion. mBio 2021; 12:e03014-20. [PMID: 33468697 PMCID: PMC7845636 DOI: 10.1128/mbio.03014-20] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Accepted: 12/11/2020] [Indexed: 01/19/2023] Open
Abstract
Orf8, one of the most puzzling genes in the SARS lineage of coronaviruses, marks a unique and striking difference in genome organization between SARS-CoV-2 and SARS-CoV-1. Here, using sequence comparisons, we unequivocally reveal the distant sequence similarities between SARS-CoV-2 Orf8 with its SARS-CoV-1 counterparts and the X4-like genes of coronaviruses, including its highly divergent "paralog" gene Orf7a, whose product is a potential immune antagonist of known structure. Supervised sequence space walks unravel identity levels that drop below 10% and yet exhibit subtle conservation patterns in this novel superfamily, characterized by an immunoglobulin-like beta sandwich topology. We document the high accuracy of the sequence space walk process in detail and characterize the subgroups of the superfamily in sequence space by systematic annotation of gene and taxon groups. While SARS-CoV-1 Orf7a and Orf8 genes are most similar to bat virus sequences, their SARS-CoV-2 counterparts are closer to pangolin virus homologs, reflecting the fine structure of conservation patterns within the SARS-CoV-2 genomes. The divergence between Orf7a and Orf8 is exceptionally idiosyncratic, since Orf7a is more constrained, whereas Orf8 is subject to rampant change, a peculiar feature that may be related to hitherto-unknown viral infection strategies. Despite their common origin, the Orf7a and Orf8 protein families exhibit different modes of evolutionary trajectories within the coronavirus lineage, which might be partly attributable to their complex interactions with the mammalian host cell, reflected by a multitude of functional associations of Orf8 in SARS-CoV-2 compared to a very small number of interactions discovered for Orf7a.IMPORTANCE Orf8 is one of the most puzzling genes in the SARS lineage of coronaviruses, including SARS-CoV-2. Using sophisticated sequence comparisons, we confirm its origins from Orf7a, another gene in the lineage that appears as more conserved, compared to Orf8. Orf7a is a potential immune antagonist of known structure, while a deletion of Orf8 was shown to decrease the severity of the infection in a cohort study. The subtle sequence similarities imply that Orf8 has the same immunoglobulin-like fold as Orf7a, confirmed by structure determination. We characterize the subgroups of this superfamily and demonstrate the highly idiosyncratic divergence patterns during the evolution of the virus.
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Affiliation(s)
- Russell Y Neches
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley California, USA
| | - Nikos C Kyrpides
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley California, USA
| | - Christos A Ouzounis
- Biological Computation and Process Laboratory, Chemical Process and Energy Resources Institute, Centre for Research and Technology Hellas, Thessalonica, Greece
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13
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Islam ABMMK, Khan MAAK, Ahmed R, Hossain MS, Kabir SMT, Islam MS, Siddiki AMAMZ. Transcriptome of nasopharyngeal samples from COVID-19 patients and a comparative analysis with other SARS-CoV-2 infection models reveal disparate host responses against SARS-CoV-2. J Transl Med 2021; 19:32. [PMID: 33413422 PMCID: PMC7790360 DOI: 10.1186/s12967-020-02695-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 12/29/2020] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Although it is becoming evident that individual's immune system has a decisive influence on SARS-CoV-2 disease progression, pathogenesis is largely unknown. In this study, we aimed to profile the host transcriptome of COVID-19 patients from nasopharyngeal samples along with virus genomic features isolated from respective host, and a comparative analyses of differential host responses in various SARS-CoV-2 infection systems. RESULTS Unique and rare missense mutations in 3C-like protease observed in all of our reported isolates. Functional enrichment analyses exhibited that the host induced responses are mediated by innate immunity, interferon, and cytokine stimulation. Surprisingly, induction of apoptosis, phagosome, antigen presentation, hypoxia response was lacking within these patients. Upregulation of immune and cytokine signaling genes such as CCL4, TNFA, IL6, IL1A, CCL2, CXCL2, IFN, and CCR1 were observed in lungs. Lungs lacked the overexpression of ACE2 as suspected, however, high ACE2 but low DPP4 expression was observed in nasopharyngeal cells. Interestingly, directly or indirectly, viral proteins specially non-structural protein mediated overexpression of integrins such as ITGAV, ITGA6, ITGB7, ITGB3, ITGA2B, ITGA5, ITGA6, ITGA9, ITGA4, ITGAE, and ITGA8 in lungs compared to nasopharyngeal samples suggesting the possible way of enhanced invasion. Furthermore, we found comparatively highly expressed transcription factors such as CBP, CEBP, NFAT, ATF3, GATA6, HDAC2, TCF12 which have pivotal roles in lung injury. CONCLUSIONS Even though this study incorporates a limited number of cases, our data will provide valuable insights in developing potential studies to elucidate the differential host responses on the viral pathogenesis in COVID-19, and incorporation of further data will enrich the search of an effective therapeutics.
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Affiliation(s)
| | | | - Rasel Ahmed
- Basic and Applied Research On Jute Project, Bangladesh Jute Research Institute, Dhaka, Bangladesh
| | - Md Sabbir Hossain
- Basic and Applied Research On Jute Project, Bangladesh Jute Research Institute, Dhaka, Bangladesh
| | - Shah Md Tamim Kabir
- Basic and Applied Research On Jute Project, Bangladesh Jute Research Institute, Dhaka, Bangladesh
| | - Md Shahidul Islam
- Basic and Applied Research On Jute Project, Bangladesh Jute Research Institute, Dhaka, Bangladesh
| | - A M A M Zonaed Siddiki
- Department of Pathology and Parasitology, Chittagong Veterinary and Animal Sciences University (CVASU), Khulshi, Chittagong, Bangladesh
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14
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Chen L, Zhong L. Genomics functional analysis and drug screening of SARS-CoV-2. Genes Dis 2020; 7:542-550. [PMID: 32363223 PMCID: PMC7195040 DOI: 10.1016/j.gendis.2020.04.002] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 04/03/2020] [Indexed: 01/11/2023] Open
Abstract
A novel coronavirus appeared in Wuhan, China has led to major outbreaks. Recently, rapid classification of virus species, analysis of genome and screening for effective drugs are the most important tasks. In the present study, through literature review, sequence alignment, ORF identification, motif recognition, secondary and tertiary structure prediction, the whole genome of SARS-CoV-2 were comprehensively analyzed. To find effective drugs, the parameters of binding sites were calculated by SeeSAR. In addition, potential miRNAs were predicted according to RNA base-pairing. After prediction by using NCBI, WebMGA and GeneMark and comparison, a total of 8 credible ORFs were detected. Even the whole genome have great difference with other CoVs, each ORF has high homology with SARS-CoVs (>90%). Furthermore, domain composition in each ORFs was also similar to SARS. In the DrugBank database, only 7 potential drugs were screened based on the sequence search module. Further predicted binding sites between drug and ORFs revealed that 2-(N-Morpholino)-ethanesulfonic acid could bind 1# ORF in 4 different regions ideally. Meanwhile, both benzyl (2-oxopropyl) carbamate and 4-(dimehylamina) benzoic acid have bene demonstrated to inhibit SARS-CoV infection effectively. Interestingly, 2 miRNAs (miR-1307-3p and miR-3613-5p) were predicted to prevent virus replication via targeting 3'-UTR of the genome or as biomarkers. In conclusion, the novel coronavirus may have consanguinity with SARS. Drugs used to treat SARS may also be effective against the novel virus. In addition, altering miRNA expression may become a potential therapeutic schedule.
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Affiliation(s)
- Long Chen
- Bioengineering Institute of Chongqing University, 174 Shazheng Street, Chongqing, China
| | - Li Zhong
- Bioengineering Institute of Chongqing University, 174 Shazheng Street, Chongqing, China
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15
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Gupta AM, Chakrabarti J, Mandal S. Non-synonymous mutations of SARS-CoV-2 leads epitope loss and segregates its variants. Microbes Infect 2020; 22:598-607. [PMID: 33049387 PMCID: PMC7547839 DOI: 10.1016/j.micinf.2020.10.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Revised: 10/05/2020] [Accepted: 10/06/2020] [Indexed: 02/06/2023]
Abstract
The non-synonymous mutations of SARS-CoV-2 isolated from across the world have been identified during the last few months. The surface glycoprotein spike of SARS-CoV-2 forms the most important hotspot for amino acid alterations followed by the ORF1a/ORF1ab poly-proteins. It is evident that the D614G mutation in spike glycoprotein and P4715L in RdRp is the important determinant of SARS-CoV-2 evolution since its emergence. P4715L in RdRp, G251V in ORF3a and S1498F of Nsp3 is associated with the epitope loss that may influence pathogenesis caused by antibody escape variants. The phylogenomics distinguished the ancestral viral samples from China and most part of Asia, isolated since the initial outbreak and the later evolved variants isolated from Europe and Americas. The evolved variants have been found to predominant globally with the loss of epitopes from its proteins. These have implications for SARS-CoV-2 transmission, pathogenesis and immune interventions.
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Affiliation(s)
- Aayatti Mallick Gupta
- Department of Chemical, Biological & Macro-Molecular Sciences, S. N. Bose National Centre for Basic Sciences, Block-JD, Sector-III, Salt Lake, Kolkata, 700 106, India
| | - Jaydeb Chakrabarti
- Department of Chemical, Biological & Macro-Molecular Sciences, S. N. Bose National Centre for Basic Sciences, Block-JD, Sector-III, Salt Lake, Kolkata, 700 106, India
| | - Sukhendu Mandal
- Laboratory of Molecular Bacteriology, Department of Microbiology, University of Calcutta, 35, Ballygunge Circular Road, Kolkata, 700019, India.
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16
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Alam I, Kamau AA, Kulmanov M, Jaremko Ł, Arold ST, Pain A, Gojobori T, Duarte CM. Functional Pangenome Analysis Shows Key Features of E Protein Are Preserved in SARS and SARS-CoV-2. Front Cell Infect Microbiol 2020; 10:405. [PMID: 32850499 PMCID: PMC7396417 DOI: 10.3389/fcimb.2020.00405] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Accepted: 06/30/2020] [Indexed: 11/13/2022] Open
Abstract
The spread of the novel coronavirus (SARS-CoV-2) has triggered a global emergency, that demands urgent solutions for detection and therapy to prevent escalating health, social, and economic impacts. The spike protein (S) of this virus enables binding to the human receptor ACE2, and hence presents a prime target for vaccines preventing viral entry into host cells. The S proteins from SARS and SARS-CoV-2 are similar, but structural differences in the receptor binding domain (RBD) preclude the use of SARS-specific neutralizing antibodies to inhibit SARS-CoV-2. Here we used comparative pangenomic analysis of all sequenced reference Betacoronaviruses, complemented with functional and structural analyses. This analysis reveals that, among all core gene clusters present in these viruses, the envelope protein E shows a variant cluster shared by SARS and SARS-CoV-2 with two completely-conserved key functional features, namely an ion-channel, and a PDZ-binding motif (PBM). These features play a key role in the activation of the inflammasome causing the acute respiratory distress syndrome, the leading cause of death in SARS and SARS-CoV-2 infections. Together with functional pangenomic analysis, mutation tracking, and previous evidence, on E protein as a determinant of pathogenicity in SARS, we suggest E protein as an alternative therapeutic target to be considered for further studies to reduce complications of SARS-CoV-2 infections in COVID-19.
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Affiliation(s)
- Intikhab Alam
- Biological and Environmental Science and Engineering (BESE), Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Allan A. Kamau
- Biological and Environmental Science and Engineering (BESE), Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Maxat Kulmanov
- Biological and Environmental Science and Engineering (BESE), Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Łukasz Jaremko
- Biological and Environmental Science and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Stefan T. Arold
- Biological and Environmental Science and Engineering (BESE), Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- Centre de Biochimie Structurale, CNRS, INSERM, Université de Montpellier, Montpellier, France
| | - Arnab Pain
- Biological and Environmental Science and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Takashi Gojobori
- Biological and Environmental Science and Engineering (BESE), Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Carlos M. Duarte
- Biological and Environmental Science and Engineering (BESE), Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
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17
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Giri R, Bhardwaj T, Shegane M, Gehi BR, Kumar P, Gadhave K, Oldfield CJ, Uversky VN. Understanding COVID-19 via comparative analysis of dark proteomes of SARS-CoV-2, human SARS and bat SARS-like coronaviruses. Cell Mol Life Sci 2020; 78:1655-1688. [PMID: 32712910 PMCID: PMC7382329 DOI: 10.1007/s00018-020-03603-x] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 07/03/2020] [Accepted: 07/17/2020] [Indexed: 01/08/2023]
Abstract
The recently emerged coronavirus designated as SARS-CoV-2 (also known as 2019 novel coronavirus (2019-nCoV) or Wuhan coronavirus) is a causative agent of coronavirus disease 2019 (COVID-19), which is rapidly spreading throughout the world now. More than 1.21 million cases of SARS-CoV-2 infection and more than 67,000 COVID-19-associated mortalities have been reported worldwide till the writing of this article, and these numbers are increasing every passing hour. The World Health Organization (WHO) has declared the SARS-CoV-2 spread as a global public health emergency and admitted COVID-19 as a pandemic now. Multiple sequence alignment data correlated with the already published reports on SARS-CoV-2 evolution indicated that this virus is closely related to the bat severe acute respiratory syndrome-like coronavirus (bat SARS-like CoV) and the well-studied human SARS coronavirus (SARS-CoV). The disordered regions in viral proteins are associated with the viral infectivity and pathogenicity. Therefore, in this study, we have exploited a set of complementary computational approaches to examine the dark proteomes of SARS-CoV-2, bat SARS-like, and human SARS CoVs by analysing the prevalence of intrinsic disorder in their proteins. According to our findings, SARS-CoV-2 proteome contains very significant levels of structural order. In fact, except for nucleocapsid, Nsp8, and ORF6, the vast majority of SARS-CoV-2 proteins are mostly ordered proteins containing less intrinsically disordered protein regions (IDPRs). However, IDPRs found in SARS-CoV-2 proteins are functionally important. For example, cleavage sites in its replicase 1ab polyprotein are found to be highly disordered, and almost all SARS-CoV-2 proteins contains molecular recognition features (MoRFs), which are intrinsic disorder-based protein–protein interaction sites that are commonly utilized by proteins for interaction with specific partners. The results of our extensive investigation of the dark side of SARS-CoV-2 proteome will have important implications in understanding the structural and non-structural biology of SARS or SARS-like coronaviruses.
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Affiliation(s)
- Rajanish Giri
- School of Basic Sciences, Indian Institute of Technology Mandi, VPO Kamand, Mandi, Himachal Pradesh, 175005, India.
| | - Taniya Bhardwaj
- School of Basic Sciences, Indian Institute of Technology Mandi, VPO Kamand, Mandi, Himachal Pradesh, 175005, India
| | - Meenakshi Shegane
- School of Basic Sciences, Indian Institute of Technology Mandi, VPO Kamand, Mandi, Himachal Pradesh, 175005, India
| | - Bhuvaneshwari R Gehi
- School of Basic Sciences, Indian Institute of Technology Mandi, VPO Kamand, Mandi, Himachal Pradesh, 175005, India
| | - Prateek Kumar
- School of Basic Sciences, Indian Institute of Technology Mandi, VPO Kamand, Mandi, Himachal Pradesh, 175005, India
| | - Kundlik Gadhave
- School of Basic Sciences, Indian Institute of Technology Mandi, VPO Kamand, Mandi, Himachal Pradesh, 175005, India
| | | | - Vladimir N Uversky
- Department of Molecular Medicine, Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, USA.,Laboratory of New Methods in Biology, Institute for Biological Instrumentation of the Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", Moscow region, Pushchino, 142290, Russia
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18
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Tan Y, Schneider T, Leong M, Aravind L, Zhang D. Novel Immunoglobulin Domain Proteins Provide Insights into Evolution and Pathogenesis of SARS-CoV-2-Related Viruses. mBio 2020; 11:e00760-20. [PMID: 32471829 PMCID: PMC7267882 DOI: 10.1128/mbio.00760-20] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Accepted: 05/08/2020] [Indexed: 12/17/2022] Open
Abstract
A novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was recently identified as the causative agent for the coronavirus disease 2019 (COVID-19) outbreak that has generated a global health crisis. We use a combination of genomic analysis and sensitive profile-based sequence and structure analysis to understand the potential pathogenesis determinants of this virus. As a result, we identify several fast-evolving genomic regions that might be at the interface of virus-host interactions, corresponding to the receptor binding domain of the Spike protein, the three tandem Macro fold domains in ORF1a, and the uncharacterized protein ORF8. Further, we show that ORF8 and several other proteins from alpha- and beta-CoVs belong to novel families of immunoglobulin (Ig) proteins. Among them, ORF8 is distinguished by being rapidly evolving, possessing a unique insert, and having a hypervariable position among SARS-CoV-2 genomes in its predicted ligand-binding groove. We also uncover numerous Ig domain proteins from several unrelated metazoan viruses, which are distinct in sequence and structure but share comparable architectures to those of the CoV Ig domain proteins. Hence, we propose that SARS-CoV-2 ORF8 and other previously unidentified CoV Ig domain proteins fall under the umbrella of a widespread strategy of deployment of Ig domain proteins in animal viruses as pathogenicity factors that modulate host immunity. The rapid evolution of the ORF8 Ig domain proteins points to a potential evolutionary arms race between viruses and hosts, likely arising from immune pressure, and suggests a role in transmission between distinct host species.IMPORTANCE The ongoing COVID-19 pandemic strongly emphasizes the need for a more complete understanding of the biology and pathogenesis of its causative agent SARS-CoV-2. Despite intense scrutiny, several proteins encoded by the genomes of SARS-CoV-2 and other SARS-like coronaviruses remain enigmatic. Moreover, the high infectivity and severity of SARS-CoV-2 in certain individuals make wet-lab studies currently challenging. In this study, we used a series of computational strategies to identify several fast-evolving regions of SARS-CoV-2 proteins which are potentially under host immune pressure. Most notably, the hitherto-uncharacterized protein encoded by ORF8 is one of them. Using sensitive sequence and structural analysis methods, we show that ORF8 and several other proteins from alpha- and beta-coronavirus comprise novel families of immunoglobulin domain proteins, which might function as potential immune modulators to delay or attenuate the host immune response against the viruses.
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Affiliation(s)
- Yongjun Tan
- Department of Biology, College of Arts and Sciences, Saint Louis University, St. Louis, Missouri, USA
| | - Theresa Schneider
- Department of Biology, College of Arts and Sciences, Saint Louis University, St. Louis, Missouri, USA
| | - Matthew Leong
- School of Medicine, Saint Louis University, St. Louis, Missouri, USA
| | - L Aravind
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland, USA
| | - Dapeng Zhang
- Department of Biology, College of Arts and Sciences, Saint Louis University, St. Louis, Missouri, USA
- Program of Bioinformatics and Computational Biology, College of Arts and Sciences, Saint Louis University, St. Louis, Missouri, USA
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19
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Tan Y, Schneider T, Leong M, Aravind L, Zhang D. Novel Immunoglobulin Domain Proteins Provide Insights into Evolution and Pathogenesis Mechanisms of SARS-Related Coronaviruses. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2020:2020.03.04.977736. [PMID: 32511297 PMCID: PMC7217140 DOI: 10.1101/2020.03.04.977736] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
A novel coronavirus (SARS-CoV-2) is the causative agent of an emergent severe respiratory disease (COVID-19) in humans that is threatening to result in a global health crisis. By using genomic, sequence, structural and evolutionary analysis, we show that Alpha- and Beta-CoVs possess several novel families of immunoglobulin (Ig) domain proteins, including ORF8 and ORF7a from SARS-related coronaviruses and two protein groups from certain Alpha-CoVs. Among them, ORF8 is distinguished in being rapidly evolving, possessing a unique insert and a hypervariable position among SARS-CoV-2 genomes in its predicted ligand-binding groove. We also uncover many Ig proteins from several metazoan viruses which are distinct in sequence and structure but share an architecture comparable to that of CoV Ig domain proteins. Hence, we propose that deployment of Ig domain proteins is a widely-used strategy by viruses, and SARS-CoV-2 ORF8 is a potential pathogenicity factor which evolves rapidly to counter the immune response and facilitate the transmission between hosts.
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Affiliation(s)
- Yongjun Tan
- Department of Biology, College of Arts and Sciences, Saint Louis University, MO 63110
| | - Theresa Schneider
- Department of Biology, College of Arts and Sciences, Saint Louis University, MO 63110
| | - Matthew Leong
- School of Medicine, Saint Louis University, MO 63110
| | - L Aravind
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894
| | - Dapeng Zhang
- Department of Biology, College of Arts and Sciences, Saint Louis University, MO 63110
- Program of Bioinformatics and Computational Biology, College of Arts and Sciences, Saint Louis University, MO 63110
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20
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Liu DX, Fung TS, Chong KKL, Shukla A, Hilgenfeld R. Accessory proteins of SARS-CoV and other coronaviruses. Antiviral Res 2014; 109:97-109. [PMID: 24995382 PMCID: PMC7113789 DOI: 10.1016/j.antiviral.2014.06.013] [Citation(s) in RCA: 292] [Impact Index Per Article: 29.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Revised: 06/17/2014] [Accepted: 06/23/2014] [Indexed: 01/21/2023]
Abstract
The huge RNA genome of SARS coronavirus comprises a number of open reading frames that code for a total of eight accessory proteins. Although none of these are essential for virus replication, some appear to have a role in virus pathogenesis. Notably, some SARS-CoV accessory proteins have been shown to modulate the interferon signaling pathways and the production of pro-inflammatory cytokines. The structural information on these proteins is also limited, with only two (p7a and p9b) having their structures determined by X-ray crystallography. This review makes an attempt to summarize the published knowledge on SARS-CoV accessory proteins, with an emphasis on their involvement in virus-host interaction. The accessory proteins of other coronaviruses are also briefly discussed. This paper forms part of a series of invited articles in Antiviral Research on "From SARS to MERS: 10 years of research on highly pathogenic human coronaviruses" (see Introduction by Hilgenfeld and Peiris (2013)).
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Affiliation(s)
- Ding Xiang Liu
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore.
| | - To Sing Fung
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore
| | - Kelvin Kian-Long Chong
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore
| | - Aditi Shukla
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, Ratzeburger Allee 160, 23538 Lübeck, Germany; German Center for Infection Research (DZIF), University of Lübeck, Germany
| | - Rolf Hilgenfeld
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, Ratzeburger Allee 160, 23538 Lübeck, Germany; German Center for Infection Research (DZIF), University of Lübeck, Germany
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Hilgenfeld R, Peiris M. From SARS to MERS: 10 years of research on highly pathogenic human coronaviruses. Antiviral Res 2013; 100:286-95. [PMID: 24012996 PMCID: PMC7113673 DOI: 10.1016/j.antiviral.2013.08.015] [Citation(s) in RCA: 241] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Accepted: 08/18/2013] [Indexed: 12/13/2022]
Abstract
We review the outbreak of severe acute respiratory syndrome (SARS) in 2002–2003 and antiviral treatment of patients. We review efforts towards the rational design of anti-SARS therapeutics. We present a comprehensive list of all available 3-dimensional structures of coronavirus proteins. We discuss the emerging MERS coronavirus and review the few antivirals available for treatment. We critically discuss which lessons have been learned from SARS and which are yet to be learned.
This article introduces a series of invited papers in Antiviral Research marking the 10th anniversary of the outbreak of severe acute respiratory syndrome (SARS), caused by a novel coronavirus that emerged in southern China in late 2002. Until that time, coronaviruses had not been recognized as agents causing severe disease in humans, hence, the emergence of the SARS-CoV came as a complete surprise. Research during the past ten years has revealed the existence of a diverse pool of coronaviruses circulating among various bat species and other animals, suggesting that further introductions of highly pathogenic coronaviruses into the human population are not merely probable, but inevitable. The recent emergence of another coronavirus causing severe disease, Middle East respiratory syndrome (MERS), in humans, has made it clear that coronaviruses pose a major threat to human health, and that more research is urgently needed to elucidate their replication mechanisms, identify potential drug targets, and develop effective countermeasures. In this series, experts in many different aspects of coronavirus replication and disease will provide authoritative, up-to-date reviews of the following topics: – clinical management and infection control of SARS; – reservoir hosts of coronaviruses; – receptor recognition and cross-species transmission of SARS-CoV; – SARS-CoV evasion of innate immune responses; – structures and functions of individual coronaviral proteins; – anti-coronavirus drug discovery and development; and – the public health legacy of the SARS outbreak. Each article will be identified in the last line of its abstract as belonging to the series “From SARS to MERS: 10 years of research on highly pathogenic human coronaviruses.”
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Affiliation(s)
- Rolf Hilgenfeld
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, Ratzeburger Allee 160, 23538 Lübeck, Germany; German Center for Infection Research (DZIF), University of Lübeck, Ratzeburger Allee 160, 23538 Lübeck, Germany.
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22
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The 7a accessory protein of severe acute respiratory syndrome coronavirus acts as an RNA silencing suppressor. J Virol 2010; 84:10395-401. [PMID: 20631126 DOI: 10.1128/jvi.00748-10] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
RNA silencing suppressors (RSSs) are well studied for plant viruses but are not well defined to date for animal viruses. Here, we have identified an RSS from a medically important positive-sense mammalian virus, Severe acute respiratory syndrome coronavirus. The viral 7a accessory protein suppressed both transgene and virus-induced gene silencing by reducing the levels of small interfering RNA (siRNA). The suppression of silencing was analyzed by two independent assays, and the middle region (amino acids [aa] 32 to 89) of 7a was responsible for suppression. Finally, the RNA suppression property and the enhancement of heterologous replicon activity by the 7a protein were confirmed for animal cell lines.
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Ulanova M, Gravelle S, Barnes R. The role of epithelial integrin receptors in recognition of pulmonary pathogens. J Innate Immun 2008; 1:4-17. [PMID: 20375562 PMCID: PMC7190199 DOI: 10.1159/000141865] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2008] [Accepted: 04/30/2008] [Indexed: 12/19/2022] Open
Abstract
Integrins are a large family of heterodimeric transmembrane cell adhesion receptors. During the last decade, it has become clear that integrins significantly participate in various host-pathogen interactions involving pathogenic bacteria, fungi, and viruses. Many bacteria possess adhesins that can bind either directly or indirectly to integrins. However, there appears to be an emerging role for integrins beyond simply adhesion molecules. Given the conserved nature of integrin structure and function, and the diversity of the pathogens which use integrins, it appears that they may act as pattern recognition receptors important for the innate immune response. Several clinically significant bacterial pathogens target lung epithelial integrins, and this review will focus on exploring various structures and mechanisms involved in these interactions.
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Affiliation(s)
- Marina Ulanova
- Northern Ontario School of Medicine, Lakehead University, Thunder Bay, Ont., Canada.
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24
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Hänel K, Willbold D. SARS-CoV accessory protein 7a directly interacts with human LFA-1. Biol Chem 2007; 388:1325-32. [DOI: 10.1515/bc.2007.157] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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25
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Schaecher SR, Mackenzie JM, Pekosz A. The ORF7b protein of severe acute respiratory syndrome coronavirus (SARS-CoV) is expressed in virus-infected cells and incorporated into SARS-CoV particles. J Virol 2007; 81:718-31. [PMID: 17079322 PMCID: PMC1797472 DOI: 10.1128/jvi.01691-06] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2006] [Accepted: 10/16/2006] [Indexed: 01/21/2023] Open
Abstract
Coronavirus replication is facilitated by a number of highly conserved viral proteins. The viruses also encode accessory genes, which are virus group specific and believed to play roles in virus replication and pathogenesis in vivo. Of the eight putative accessory proteins encoded by the severe acute respiratory distress syndrome associated coronavirus (SARS-CoV), only two-open reading frame 3a (ORF3a) and ORF7a-have been identified in virus-infected cells to date. The ORF7b protein is a putative viral accessory protein encoded on subgenomic (sg) RNA 7. The ORF7b initiation codon overlaps the ORF7a stop codon in a -1 shifted ORF. We demonstrate that the ORF7b protein is expressed in virus-infected cell lysates and from a cDNA encoding the gene 7 coding region, indicating that the sgRNA7 is bicistronic. The translation of ORF7b appears to be mediated by ribosome leaky scanning, and the protein has biochemical properties consistent with that of an integral membrane protein. ORF7b localizes to the Golgi compartment and is incorporated into SARS-CoV particles. We therefore conclude that the ORF7b protein is not only an accessory protein but a structural component of the SARS-CoV virion.
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Affiliation(s)
- Scott R Schaecher
- Department of Molecular Microbiology, Washington University School of Medicine, Campus Box 8230, 660 S. Euclid Ave., St. Louis, MO 63110-1093, USA
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The ORF7b protein of severe acute respiratory syndrome coronavirus (SARS-CoV) is expressed in virus-infected cells and incorporated into SARS-CoV particles. J Virol 2006. [PMID: 17079322 DOI: 10.1128/jvi.01691‐06] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Coronavirus replication is facilitated by a number of highly conserved viral proteins. The viruses also encode accessory genes, which are virus group specific and believed to play roles in virus replication and pathogenesis in vivo. Of the eight putative accessory proteins encoded by the severe acute respiratory distress syndrome associated coronavirus (SARS-CoV), only two-open reading frame 3a (ORF3a) and ORF7a-have been identified in virus-infected cells to date. The ORF7b protein is a putative viral accessory protein encoded on subgenomic (sg) RNA 7. The ORF7b initiation codon overlaps the ORF7a stop codon in a -1 shifted ORF. We demonstrate that the ORF7b protein is expressed in virus-infected cell lysates and from a cDNA encoding the gene 7 coding region, indicating that the sgRNA7 is bicistronic. The translation of ORF7b appears to be mediated by ribosome leaky scanning, and the protein has biochemical properties consistent with that of an integral membrane protein. ORF7b localizes to the Golgi compartment and is incorporated into SARS-CoV particles. We therefore conclude that the ORF7b protein is not only an accessory protein but a structural component of the SARS-CoV virion.
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Tan YJ, Lim SG, Hong W. Understanding the accessory viral proteins unique to the severe acute respiratory syndrome (SARS) coronavirus. Antiviral Res 2006; 72:78-88. [PMID: 16820226 PMCID: PMC7114237 DOI: 10.1016/j.antiviral.2006.05.010] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2006] [Revised: 04/29/2006] [Accepted: 05/15/2006] [Indexed: 12/14/2022]
Abstract
A novel coronavirus, termed the severe acute respiratory syndrome coronavirus (SARS-CoV), infected humans in Guangdong, China, in November 2002 and the subsequent efficient human-to-human transmissions of this virus caused profound disturbances in over 30 countries worldwide in 2003. Eventually, this epidemic was controlled by isolation and there has been no human infection reported since January 2004. However, research on different aspects of the SARS-CoV is not waning, as it is not known if this virus will re-emerge, especially since its origins and potential reservoir(s) are unresolved. The SARS-CoV genome is nearly 30 kb in length and contains 14 potential open reading frames (ORFs). Some of these ORFs encode for genes that are homologous to proteins found in all known coronaviruses, namely the replicase genes (ORFs 1a and 1b) and the four structural proteins: nucleocapsid, spike, membrane and envelope, and these proteins are expected to be essential for the replication of the virus. The remaining eight ORFs encodes for accessory proteins, varying in length from 39 to 274 amino acids, which are unique to SARS-CoV. This review will summarize the expeditious research on these accessory viral proteins in three major areas: (i) the detection of antibodies against accessory proteins in the serum of infected patients, (ii) the expression, processing and cellular localization of the accessory proteins, and (iii) the effects of the accessory proteins on cellular functions. These in-depth molecular and biochemical characterizations of the SARS-CoV accessory proteins, which have no homologues in other coronaviruses, may offer clues as to why the SARS-CoV causes such a severe and rapid attack in humans, while other coronaviruses that infect humans seem to be more forgiving.
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Affiliation(s)
- Yee-Joo Tan
- Institute of Molecular and Cell Biology, 61 Biopolis Drive, Proteos, Singapore 138673, Singapore.
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28
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Modern High Resolution NMR for the Study of Structure, Dynamics and Interactions of Biological Macromolecules. Z PHYS CHEM 2006. [DOI: 10.1524/zpch.2006.220.5.567] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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