1
|
Ahmed-Belkacem R, Sutto-Ortiz P, Delpal A, Troussier J, Canard B, Vasseur JJ, Decroly E, Debart F. 5'-cap RNA/SAM mimetic conjugates as bisubstrate inhibitors of viral RNA cap 2'-O-methyltransferases. Bioorg Chem 2024; 143:107035. [PMID: 38199140 DOI: 10.1016/j.bioorg.2023.107035] [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: 10/23/2023] [Revised: 11/24/2023] [Accepted: 12/12/2023] [Indexed: 01/12/2024]
Abstract
Viral RNA cap 2'-O-methyltransferases are considered promising therapeutic targets for antiviral treatments, as they play a key role in the formation of viral RNA cap-1 structures to escape the host immune system. A better understanding of how they interact with their natural substrates (RNA and the methyl donor SAM) would enable the rational development of potent inhibitors. However, as few structures of 2'-O-MTases in complex with RNA have been described, little is known about substrate recognition by these MTases. For this, chemical tools mimicking the state in which the cap RNA substrate and SAM cofactor are bound in the enzyme's catalytic pocket may prove useful. In this work, we designed and synthesized over 30 RNA conjugates that contain a short oligoribonucleotide (ORN with 4 or 6 nucleotides) with the first nucleotide 2'-O-attached to an adenosine by linkers of different lengths and containing S or N-heteroatoms, or a 1,2,3-triazole ring. These ORN conjugates bearing or not a cap structure at 5'-extremity mimic the methylation transition state with RNA substrate/SAM complex as bisubstrates of 2'-O-MTases. The ORN conjugates were synthesized either by the incorporation of a dinucleoside phosphoramidite during RNA elongation or by click chemistry performed on solid-phase post-RNA elongation. Their ability to inhibit the activity of the nsp16/nsp10 complex of SARS-CoV-2 and the NS5 protein of dengue and Zika viruses was assessed. Significant submicromolar IC50 values and Kd values in the µM range were found, suggesting a possible interaction of some ORN conjugates with these viral 2'-O-MTases.
Collapse
Affiliation(s)
| | | | - Adrien Delpal
- AFMB, University of Aix-Marseille, CNRS, Marseille, France
| | - Joris Troussier
- IBMM, University of Montpellier, CNRS, ENSCM, Montpellier, France
| | - Bruno Canard
- AFMB, University of Aix-Marseille, CNRS, Marseille, France
| | | | | | - Françoise Debart
- IBMM, University of Montpellier, CNRS, ENSCM, Montpellier, France.
| |
Collapse
|
2
|
Zong K, Li W, Xu Y, Zhao X, Cao R, Yan H, Li X. Design, Synthesis, Evaluation and Molecular Dynamics Simulation of Dengue Virus NS5-RdRp Inhibitors. Pharmaceuticals (Basel) 2023; 16:1625. [PMID: 38004490 PMCID: PMC10674617 DOI: 10.3390/ph16111625] [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: 10/16/2023] [Revised: 11/08/2023] [Accepted: 11/14/2023] [Indexed: 11/26/2023] Open
Abstract
Dengue virus (DENV) is a major mosquito-borne human pathogen in tropical countries; however, there are currently no targeted antiviral treatments for DENV infection. Compounds 27 and 29 have been reported to be allosteric inhibitors of DENV RdRp with potent inhibitory effects. In this study, the structures of compounds 27 and 29 were optimized using computer-aided drug design (CADD) approaches. Nine novel compounds were synthesized based on rational considerations, including molecular docking scores, free energy of binding to receptor proteins, predicted Absorption, Distribution, Metabolism, Excretion, and Toxicity (ADMET) parameters, structural diversity, and feasibility of synthesis. Subsequently, the anti-DENV activity was assessed. In the cytopathic effect (CPE) assay conducted on BHK-21 cells using the DENV2 NGC strain, both SW-b and SW-d demonstrated comparable or superior activity against DENV2, with IC50 values of 3.58 ± 0.29 μM and 23.94 ± 1.00 μM, respectively, compared to that of compound 27 (IC50 = 19.67 ± 1.12 μM). Importantly, both SW-b and SW-d exhibited low cytotoxicity, with CC50 values of 24.65 μmol and 133.70 μmol, respectively, resulting in selectivity indices of 6.89 and 5.58, respectively. Furthermore, when compared to the positive control compound 3'-dATP (IC50 = 30.09 ± 8.26 μM), SW-b and SW-d displayed superior inhibitory activity in an enzyme inhibitory assay, with IC50 values of 11.54 ± 1.30 μM and 13.54 ± 0.32 μM, respectively. Molecular dynamics (MD) simulations elucidated the mode of action of SW-b and SW-d, highlighting their ability to enhance π-π packing interactions between benzene rings and residue W795 in the S1 fragment, compared to compounds 27 and 29. Although the transacylsulphonamide fragment reduced the interaction between T794 and NH, it augmented the interaction between R729 and T794. In summary, our study underscores the potential of SW-b and SW-d as allosteric inhibitors targeting the DENV NS5 RdRp domain. However, further in vivo studies are warranted to assess their pharmacology and toxicity profiles.
Collapse
Affiliation(s)
- Keli Zong
- Faculty of Environment and Life, Beijing University of Technology, 100 Pingleyuan, Beijing 100124, China;
- Beijing Institute of Pharmacology and Toxicology, 27 Taiping Road, Beijing 100850, China; (W.L.); (Y.X.); (R.C.)
| | - Wei Li
- Beijing Institute of Pharmacology and Toxicology, 27 Taiping Road, Beijing 100850, China; (W.L.); (Y.X.); (R.C.)
| | - Yijie Xu
- Beijing Institute of Pharmacology and Toxicology, 27 Taiping Road, Beijing 100850, China; (W.L.); (Y.X.); (R.C.)
| | - Xu Zhao
- Department of Hepatology, Fifth Medical Center of Chinese PLA General Hospital, 100 West Fourth Ring Road, Beijing 100071, China;
| | - Ruiyuan Cao
- Beijing Institute of Pharmacology and Toxicology, 27 Taiping Road, Beijing 100850, China; (W.L.); (Y.X.); (R.C.)
| | - Hong Yan
- Faculty of Environment and Life, Beijing University of Technology, 100 Pingleyuan, Beijing 100124, China;
| | - Xingzhou Li
- Beijing Institute of Pharmacology and Toxicology, 27 Taiping Road, Beijing 100850, China; (W.L.); (Y.X.); (R.C.)
| |
Collapse
|
3
|
da Silva PG, Chaves EJF, Silva TMS, Rocha GB, Dantas WM, de Oliveira RN, Pena LJ. Antiviral Activity of Flavonoids from Geopropolis of the Brazilian Jandaira Bee against Zika and Dengue Viruses. Pharmaceutics 2023; 15:2494. [PMID: 37896254 PMCID: PMC10609720 DOI: 10.3390/pharmaceutics15102494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 07/20/2023] [Accepted: 07/28/2023] [Indexed: 10/29/2023] Open
Abstract
Arthropod-borne viruses within the Flaviviridae family such as Zika (ZIKV) and dengue (DENV) are responsible for major outbreaks in tropical countries, and there are no specific treatments against them. Naringenin and 7-O-methyl naringenin are flavonoids that can be extracted from geopropolis, a natural material that the Brazilian Jandaira stingless bee (Melipona subnitida Ducke) produces to protect its nest. Here, these flavonoids were tested against ZIKV and DENV using Vero cells as a cellular model to perform a cytotoxicity assay and to define the effective concentrations of TCID50 as the readout method. The results demonstrated the antiviral activity of the compounds against both viruses upon the treatment of infected cells. The tested flavonoids had antiviral activity comparable with 6-methylmercaptopurine riboside (6-MMPr), used here as a positive control. In addition, to identify the possible action mechanism of the antiviral candidates, we carried out a docking analysis followed by a molecular dynamics simulation to elucidate naringenin and 7-O-methyl naringenin binding sites to each virus. Altogether, these results demonstrate that both flavonoids have potent antiviral effects against both viruses and warrant further in vivo trials.
Collapse
Affiliation(s)
- Poliana Gomes da Silva
- Laboratory of Virology and Experimental Therapy (Lavite), Department of Virology, Aggeu Magalhães Institute (IAM), Oswaldo Cruz Foundation (Fiocruz), Recife 50670-420, Pernambuco, Brazil; (P.G.d.S.); (E.J.F.C.); (W.M.D.)
| | - Elton José Ferreira Chaves
- Laboratory of Virology and Experimental Therapy (Lavite), Department of Virology, Aggeu Magalhães Institute (IAM), Oswaldo Cruz Foundation (Fiocruz), Recife 50670-420, Pernambuco, Brazil; (P.G.d.S.); (E.J.F.C.); (W.M.D.)
| | - Tania Maria Sarmento Silva
- Phytochemical Bioprospecting Laboratory, Department of Chemistry, Federal Rural University of Pernambuco, Recife 52171-900, Pernambuco, Brazil;
| | - Gerd Bruno Rocha
- Laboratory of Computational Quantum Chemistry, Department of Chemistry, Federal University of Paraiba, João Pessoa 58050-085, Paraiba, Brazil;
| | - Willyenne Marília Dantas
- Laboratory of Virology and Experimental Therapy (Lavite), Department of Virology, Aggeu Magalhães Institute (IAM), Oswaldo Cruz Foundation (Fiocruz), Recife 50670-420, Pernambuco, Brazil; (P.G.d.S.); (E.J.F.C.); (W.M.D.)
- Bioactive Compounds Synthesis Laboratory, Department of Chemistry, Federal Rural University of Pernambuco (UFRPE), Recife 52171-900, Pernambuco, Brazil;
| | - Ronaldo Nascimento de Oliveira
- Bioactive Compounds Synthesis Laboratory, Department of Chemistry, Federal Rural University of Pernambuco (UFRPE), Recife 52171-900, Pernambuco, Brazil;
| | - Lindomar José Pena
- Laboratory of Virology and Experimental Therapy (Lavite), Department of Virology, Aggeu Magalhães Institute (IAM), Oswaldo Cruz Foundation (Fiocruz), Recife 50670-420, Pernambuco, Brazil; (P.G.d.S.); (E.J.F.C.); (W.M.D.)
| |
Collapse
|
4
|
Chen H, Lin S, Yang F, Chen Z, Guo L, Yang J, Lin X, Wang L, Duan Y, Wen A, Zhang X, Dai Y, Yin K, Yuan X, Yu C, He Y, He B, Cao Y, Dong H, Li J, Zhao Q, Liu Q, Lu G. Structural and functional basis of low-affinity SAM/SAH-binding in the conserved MTase of the multi-segmented Alongshan virus distantly related to canonical unsegmented flaviviruses. PLoS Pathog 2023; 19:e1011694. [PMID: 37831643 PMCID: PMC10575543 DOI: 10.1371/journal.ppat.1011694] [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: 03/10/2023] [Accepted: 09/18/2023] [Indexed: 10/15/2023] Open
Abstract
Alongshan virus (ALSV), a newly discovered member of unclassified Flaviviridae family, is able to infect humans. ALSV has a multi-segmented genome organization and is evolutionarily distant from canonical mono-segmented flaviviruses. The virus-encoded methyltransferase (MTase) plays an important role in viral replication. Here we show that ALSV MTase readily binds S-adenosyl-L-methionine (SAM) and S-adenosyl-L-homocysteine (SAH) but exhibits significantly lower affinities than canonical flaviviral MTases. Structures of ALSV MTase in the free and SAM/SAH-bound forms reveal that the viral enzyme possesses a unique loop-element lining side-wall of the SAM/SAH-binding pocket. While the equivalent loop in flaviviral MTases half-covers SAM/SAH, contributing multiple hydrogen-bond interactions; the pocket-lining loop of ALSV MTase is of short-length and high-flexibility, devoid of any physical contacts with SAM/SAH. Subsequent mutagenesis data further corroborate such structural difference affecting SAM/SAH-binding. Finally, we also report the structure of ALSV MTase bound with sinefungin, an SAM-analogue MTase inhibitor. These data have delineated the basis for the low-affinity interaction between ALSV MTase and SAM/SAH and should inform on antiviral drug design.
Collapse
Affiliation(s)
- Hua Chen
- Department of Emergency Medicine, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Department of Wound Repair and Rehabilitation Medicine, State Key Laboratory of Trauma, Burns and Combined Injury, Daping Hospital, Army Medical University, Chongqing, China
| | - Sheng Lin
- Department of Emergency Medicine, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Fanli Yang
- Department of Emergency Medicine, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Zimin Chen
- Department of Emergency Medicine, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Liyan Guo
- Department of Emergency Medicine, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Jing Yang
- Department of Emergency Medicine, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Xi Lin
- Department of Emergency Medicine, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Lingling Wang
- Department of Emergency Medicine, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Yanping Duan
- Department of Emergency Medicine, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Ao Wen
- Department of Emergency Medicine, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Xindan Zhang
- Department of Emergency Medicine, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Yushan Dai
- Department of Emergency Medicine, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Keqing Yin
- Department of Emergency Medicine, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Xin Yuan
- Department of Emergency Medicine, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Chongzhang Yu
- Department of Emergency Medicine, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Yarong He
- Department of Emergency Medicine, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Bin He
- Department of Emergency Medicine, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Yu Cao
- Department of Emergency Medicine, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Disaster Medicine Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Haohao Dong
- State Key Laboratory of Biotherapy and Cancer Center, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Jian Li
- School of Basic Medical Sciences, Chengdu University, Chengdu, Sichuan, China
| | - Qi Zhao
- College of Food and Biological Engineering, Chengdu University, Chengdu, Sichuan, China
| | - Quan Liu
- Center of Infectious diseases and Pathogen Biology, Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education, The First Hospital of Jilin University, State Key Laboratory of Zoonotic Diseases, Changchun, Jilin, China
| | - Guangwen Lu
- Department of Emergency Medicine, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| |
Collapse
|
5
|
Fang X, Lu G, Deng Y, Yang S, Hou C, Gong P. Unusual substructure conformations observed in crystal structures of a dicistrovirus RNA-dependent RNA polymerase suggest contribution of the N-terminal extension in proper folding. Virol Sin 2023; 38:531-540. [PMID: 37156298 PMCID: PMC10436059 DOI: 10.1016/j.virs.2023.05.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 05/04/2023] [Indexed: 05/10/2023] Open
Abstract
The Dicistroviridae is a virus family that includes many insect pathogens. These viruses contain a positive-sense RNA genome that is replicated by the virally encoded RNA-dependent RNA polymerase (RdRP) also named 3Dpol. Compared with the Picornaviridae RdRPs such as poliovirus (PV) 3Dpol, the Dicistroviridae representative Israeli acute paralysis virus (IAPV) 3Dpol has an additional N-terminal extension (NE) region that is about 40-residue in length. To date, both the structure and catalytic mechanism of the Dicistroviridae RdRP have remain elusive. Here we reported crystal structures of two truncated forms of IAPV 3Dpol, namely Δ85 and Δ40, both missing the NE region, and the 3Dpol protein in these structures exhibited three conformational states. The palm and thumb domains of these IAPV 3Dpol structures are largely consistent with those of the PV 3Dpol structures. However, in all structures, the RdRP fingers domain is partially disordered, while different conformations of RdRP substructures and interactions between them are also present. In particular, a large-scale conformational change occurred in the motif B-middle finger region in one protein chain of the Δ40 structure, while a previously documented alternative conformation of motif A was observed in all IAPV structures. These experimental data on one hand show intrinsic conformational variances of RdRP substructures, and on the other hand suggest possible contribution of the NE region in proper RdRP folding in IAPV.
Collapse
Affiliation(s)
- Xiang Fang
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430207, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Guoliang Lu
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430207, China
| | - Yanchun Deng
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha, 410205, China
| | - Sa Yang
- Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Chunsheng Hou
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha, 410205, China.
| | - Peng Gong
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430207, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Hubei Jiangxia Laboratory, Wuhan, 430207, China.
| |
Collapse
|
6
|
Decombe A, El Kazzi P, Decroly E. Interplay of RNA 2'-O-methylations with viral replication. Curr Opin Virol 2023; 59:101302. [PMID: 36764118 DOI: 10.1016/j.coviro.2023.101302] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 12/06/2022] [Accepted: 12/19/2022] [Indexed: 02/11/2023]
Abstract
Viral RNAs (vRNAs) are decorated by post-transcriptional modifications, including methylation of nucleotides. Methylations regulate biological functions linked to the sequence, structure, and protein interactome of RNA. Several RNA viruses were found to harbor 2'-O-methylations, affecting the ribose moiety of RNA. This mark was initially shown to target the first and second nucleotides of the 5'-end cap structure of mRNA. More recently, nucleotides within vRNA were also reported to carry 2'-O-methylations. The consequences of such methylations are still puzzling since they were associated with both proviral and antiviral effects. Here, we focus on the mechanisms governing vRNA 2'-O-methylation and we explore the possible roles of this epitranscriptomic modification for viral replication.
Collapse
Affiliation(s)
- Alice Decombe
- AFMB, CNRS, Aix-Marseille University, UMR 7257, Case 925, 163 Avenue de Luminy, 13288 Marseille Cedex 09, France
| | - Priscila El Kazzi
- AFMB, CNRS, Aix-Marseille University, UMR 7257, Case 925, 163 Avenue de Luminy, 13288 Marseille Cedex 09, France
| | - Etienne Decroly
- AFMB, CNRS, Aix-Marseille University, UMR 7257, Case 925, 163 Avenue de Luminy, 13288 Marseille Cedex 09, France.
| |
Collapse
|
7
|
Serological Cross-Reactivity in Zoonotic Flaviviral Infections of Medical Importance. Antibodies (Basel) 2023; 12:antib12010018. [PMID: 36975365 PMCID: PMC10045537 DOI: 10.3390/antib12010018] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 02/17/2023] [Accepted: 02/20/2023] [Indexed: 03/03/2023] Open
Abstract
Flaviviruses are enveloped RNA viruses from the family Flaviviridae that comprise many important human pathogenic arboviruses such as Yellow Fever, Dengue, and Zika viruses. Because they belong to the same genus, these viruses show sequence and structural homology among them, which results in serological cross-reactivity. Upon infection, the immune system produces both species-specific and cross-reactive antibodies, and depending on the virus, in a successive flavivirus infection, cross-reactive antibodies either enhance protection or exacerbate the disease—the latter usually due to antibody-dependent enhancement. These antigenic relationships between different flaviviruses that lead to serological cross-reactivity make them difficult to be identified through serological methods, especially when it comes to successive flavivirus infections. We present here an overview of the main structural, epidemiological, and immunological aspects of flaviviruses, highlighting the role of neutralizing antibodies in fighting viral infections and in the “original antigenic sin” problem. Finally, we draw attention to the importance of developing a rapid serological diagnostic test for flaviviruses with high sensitivity and specificity, especially when considering that cross-reactive immunity can influence the outcome of these infections.
Collapse
|
8
|
Furtado ND, de Mello IS, de Godoy AS, Noske GD, Oliva G, Canard B, Decroly E, Bonaldo MC. Amino Acid Polymorphisms on the Brazilian Strain of Yellow Fever Virus Methyltransferase Are Related to the Host's Immune Evasion Mediated by Type I Interferon. Viruses 2023; 15:191. [PMID: 36680231 PMCID: PMC9863089 DOI: 10.3390/v15010191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 01/03/2023] [Accepted: 01/07/2023] [Indexed: 01/12/2023] Open
Abstract
Since late 2016, a yellow fever virus (YFV) variant carrying a set of nine amino acid variations has circulated in South America. Three of them were mapped on the methyltransferase (MTase) domain of viral NS5 protein. To assess whether these changes affected viral infectivity, we synthesized YFV carrying the MTase of circulating lineage as well as its isoform with the residues of the previous strains (NS5 K101R, NS5 V138I, and NS5 G173S). We observed a slight difference in viral growth properties and plaque phenotype between the two synthetic YFVs. However, the MTase polymorphisms associated with the Brazilian strain of YFV (2016-2019) confer more susceptibility to the IFN-I. In addition, in vitro MTase assay revealed that the interaction between the YFV MTase and the methyl donor molecule (SAM) is altered in the Brazilian MTase variant. Altogether, the results reported here describe that the MTase carrying the molecular signature of the Brazilian YFV circulating since 2016 might display a slight decrease in its catalytic activity but virtually no effect on viral fitness in the parameters comprised in this study. The most marked influence of these residues stands in the immune escape against the antiviral response mediated by IFN-I.
Collapse
Affiliation(s)
- Nathália Dias Furtado
- Laboratório de Biologia Molecular de Flavivírus, Instituto Oswaldo Cruz-Fiocruz, Rio de Janeiro 21040-900, Brazil
| | - Iasmim Silva de Mello
- Laboratório de Biologia Molecular de Flavivírus, Instituto Oswaldo Cruz-Fiocruz, Rio de Janeiro 21040-900, Brazil
| | - Andre Schutzer de Godoy
- Centro de Pesquisa e Inovação em Biodiversidade e Fármacos, Instituto de Física de São Carlos-USP, São Paulo 13563-120, Brazil
| | - Gabriela Dias Noske
- Centro de Pesquisa e Inovação em Biodiversidade e Fármacos, Instituto de Física de São Carlos-USP, São Paulo 13563-120, Brazil
| | - Glaucius Oliva
- Centro de Pesquisa e Inovação em Biodiversidade e Fármacos, Instituto de Física de São Carlos-USP, São Paulo 13563-120, Brazil
| | - Bruno Canard
- Architecture et Fonction des Macromolécules Biologiques, Aix-Marseille Université, CNRS, UMR7257, 13009 Marseille, France
| | - Etienne Decroly
- Architecture et Fonction des Macromolécules Biologiques, Aix-Marseille Université, CNRS, UMR7257, 13009 Marseille, France
| | - Myrna C. Bonaldo
- Laboratório de Biologia Molecular de Flavivírus, Instituto Oswaldo Cruz-Fiocruz, Rio de Janeiro 21040-900, Brazil
| |
Collapse
|
9
|
Ullah A, Atia-tul-Wahab, Gong P, Khan AM, Choudhary MI. Identification of new inhibitors of NS5 from dengue virus using saturation transfer difference (STD-NMR) and molecular docking studies. RSC Adv 2022; 13:355-369. [PMID: 36605638 PMCID: PMC9768849 DOI: 10.1039/d2ra04836a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 11/15/2022] [Indexed: 12/24/2022] Open
Abstract
The rapid spread of dengue virus has now emerged as a major health problem worldwide, particularly in tropical and sub-tropical regions. Nearly half of the human population is at risk of getting infection. Among the proteomes of dengue virus, nonstructural protein NS5 is conserved across the genus Flavivirus. NS5 comprises methyltransferase enzyme (MTase) domain, which helps in viral RNA capping, and RNA-dependent RNA polymerase (RdRp) domain, which is important for the virus replication. Negative modulation of NS5 decreases its activity and associated functions. Despite recent advances, there is still an immense need for effective approaches toward drug discovery against dengue virus. Drug repurposing is an approach to identify the new therapeutic indications of already approved drugs, for the treatment of both common and rare diseases, and can potentially lower the cost, and time required for drug discovery and development. In this study, we evaluated 75 compounds (grouped into 15 mixtures), including 13 natural compounds and 62 drugs, by using biophysical methods, for their ability to interact with NS5 protein, which were further validated by molecular docking and simulation studies. Our current study led to the identification of 12 ligands, including both 9 US-FDA approved drugs and 3 natural products that need to be further studied as potential antiviral agents against dengue virus.
Collapse
Affiliation(s)
- Asmat Ullah
- Dr Panjwani Center for Molecular Medicine and Drug Research, International Center of Chemical and Biological Sciences, University of KarachiKarachi75270Pakistan
| | - Atia-tul-Wahab
- Dr Panjwani Center for Molecular Medicine and Drug Research, International Center of Chemical and Biological Sciences, University of KarachiKarachi75270Pakistan
| | - Peng Gong
- Wuhan Institute of Virology, Chinese Academy of SciencesWuhanHubei 430071China
| | - Abdul Mateen Khan
- H.E.J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of KarachiKarachi75270Pakistan
| | - M. Iqbal Choudhary
- Dr Panjwani Center for Molecular Medicine and Drug Research, International Center of Chemical and Biological Sciences, University of KarachiKarachi75270Pakistan,H.E.J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of KarachiKarachi75270Pakistan,Department of Biochemistry, Faculty of Science, King Abdulaziz UniversityJeddah-21589Saudi Arabia
| |
Collapse
|
10
|
Ferrero DS, Albentosa-González L, Mas A, Verdaguer N. Structure and function of the NS5 methyltransferase domain from Usutu virus. Antiviral Res 2022; 208:105460. [DOI: 10.1016/j.antiviral.2022.105460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 10/24/2022] [Accepted: 10/31/2022] [Indexed: 11/09/2022]
|
11
|
Abstract
The positive-sense flavivirus RNA genome bears a cap 1 structure essential for RNA stability and viral protein translation, and the formation of cap 1 requires the virally encoded nonstructural protein NS5 harboring guanylyltransferase (GTase), cap guanine N7 methyltransferase (N7 MTase), and 5'-nucleotide ribose 2'-O MTase activities in its single-domain MTase module. Despite numerous MTase-containing structures reported, the structural evidence for a critical GMP-enzyme intermediate formation and RNA repositioning when transitioning among different reactions is missing. Here, we report 10 high-resolution MTase crystal structures of Omsk hemorrhagic fever virus (OHFV), a representative high-consequence tick-borne flavivirus, capturing previously unidentified GMP-arginine adduct structures and a rarely observed capped RNA conformation. These structures help us thread capping events in the canonical model with a structure-based hypothesis involving the flipping of the 5' nucleotide, while the observation of an m7GMP-arginine adduct is compatible with an alternate capping model that decouples the N7 and 2'-O methylation steps. IMPORTANCE The methyltransferase (MTase) domain of flavivirus NS5 is unique in harboring guanylyltransferase (GTase), N7 MTase, and 2'-O MTase activities, playing a central role in viral RNA capping. However, the detailed mechanisms of the multistep capping process remain elusive. Here, we report 10 crystal structures of a flavivirus MTase to help understand the guanylyl transfer from GTP to the GTase itself and the transition between guanylyl transfer and methylation steps. In particular, a previously unobserved GMP-arginine covalent intermediate was captured multiple times in MTase crystal soaking trials with GTP present in the soaking solution, supporting its role in bridging the guanylyl transfer from GTP to the GTase and subsequent transfer to the 5'-diphosphate RNA.
Collapse
|
12
|
The Dengue Virus Nonstructural Protein 1 (NS1) Interacts with the Putative Epigenetic Regulator DIDO1 to Promote Flavivirus Replication in Mosquito Cells. J Virol 2022; 96:e0070422. [PMID: 35652656 DOI: 10.1128/jvi.00704-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Dengue virus (DENV) NS1 is a multifunctional protein essential for viral replication. To gain insights into NS1 functions in mosquito cells, the protein interactome of DENV NS1 in C6/36 cells was investigated using a proximity biotinylation system and mass spectrometry. A total of 817 mosquito targets were identified as protein-protein interacting with DENV NS1. Approximately 14% of them coincide with interactomes previously obtained in vertebrate cells, including the oligosaccharide transferase complex, the chaperonin containing TCP-1, vesicle localization, and ribosomal proteins. Notably, other protein pathways not previously reported in vertebrate cells, such as epigenetic regulation and RNA silencing, were also found in the NS1 interactome in mosquito cells. Due to the novel and strong interactions observed for NS1 and the epigenetic regulator DIDO1 (Death-Inducer Obliterator 1), the role of DIDO1 in viral replication was further explored. Interactions between NS1 and DIDO1 were corroborated in infected mosquito cells, by colocalization and proximity ligation assays. Silencing DIDO1 expression results in a significant reduction in DENV and ZIKV replication and progeny production. Comparison of transcription analysis of mock or DENV infected cells silenced for DIDO1 revealed variations in multiple gene expression pathways, including pathways associated with DENV infection such as RNA surveillance, IMD, and Toll. These results suggest that DIDO1 is a host factor involved in the negative modulation of the antiviral response necessary for flavivirus replication in mosquito cells. Our findings uncover novel mechanisms of NS1 to promote DENV and ZIKV replication, and add to the understanding of NS1 as a multifunctional protein. IMPORTANCE Dengue is the most important mosquito-borne viral disease to humans. Dengue virus NS1 is a multifunctional protein essential for replication and modulation of innate immunity. To gain insights into NS1 functions, the protein interactome of dengue virus NS1 in Aedes albopictus cells was investigated using a proximity biotinylation system and mass spectrometry. Several protein pathways, not previously observed in vertebrate cells, such as transcription and epigenetic regulation, were found as part of the NS1 interactome in mosquito cells. Among those, DIDO1 was found to be a necessary host factor for dengue and Zika virus replication in mosquito cells. Transcription analysis of infected mosquito cells silenced for DIDO1 revealed alterations of the IMD and Toll pathways, part of the antiviral response in mosquitoes. The results suggest that DIDO1 is a host factor involved in modulation of the antiviral response and necessary for flavivirus replication.
Collapse
|
13
|
Cataneo AHD, Ávila EP, Mendes LADO, de Oliveira VG, Ferraz CR, de Almeida MV, Frabasile S, Duarte Dos Santos CN, Verri WA, Bordignon J, Wowk PF. Flavonoids as Molecules With Anti- Zika virus Activity. Front Microbiol 2021; 12:710359. [PMID: 34566915 PMCID: PMC8462986 DOI: 10.3389/fmicb.2021.710359] [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: 05/16/2021] [Accepted: 08/03/2021] [Indexed: 11/13/2022] Open
Abstract
Zika virus (ZIKV) is an arthropod-born virus that is mainly transmitted to humans by mosquitoes of the genus Aedes spp. Since its first isolation in 1947, only a few human cases had been described until large outbreaks occurred on Yap Island (2007), French Polynesia (2013), and Brazil (2015). Most ZIKV-infected individuals are asymptomatic or present with a self-limiting disease and nonspecific symptoms such as fever, myalgia, and headache. However, in French Polynesia and Brazil, ZIKV outbreaks led to the diagnosis of congenital malformations and microcephaly in newborns and Guillain-Barré syndrome (GBS) in adults. These new clinical presentations raised concern from public health authorities and highlighted the need for anti-Zika treatments and vaccines to control the neurological damage caused by the virus. Despite many efforts in the search for an effective treatment, neither vaccines nor antiviral drugs have become available to control ZIKV infection and/or replication. Flavonoids, a class of natural compounds that are well-known for possessing several biological properties, have shown activity against different viruses. Additionally, the use of flavonoids in some countries as food supplements indicates that these molecules are nontoxic to humans. Thus, here, we summarize knowledge on the use of flavonoids as a source of anti-ZIKV molecules and discuss the gaps and challenges in this area before these compounds can be considered for further preclinical and clinical trials.
Collapse
Affiliation(s)
| | - Eloah Pereira Ávila
- Departamento de Química, Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil
| | | | | | - Camila Rodrigues Ferraz
- Departamento de Ciências Patológicas, Centro de Ciências Biológicas, Universidade Estadual de Londrina, Londrina, Brazil
| | | | - Sandra Frabasile
- Sección Virologia, Facultad de Ciencias, Universidad de La República, Montevideo, Uruguay
| | | | - Waldiceu Aparecido Verri
- Departamento de Ciências Patológicas, Centro de Ciências Biológicas, Universidade Estadual de Londrina, Londrina, Brazil
| | - Juliano Bordignon
- Laboratório de Virologia Molecular, Instituto Carlos Chagas/Fiocruz-PR, Curitiba, Brazil
| | - Pryscilla Fanini Wowk
- Laboratório de Virologia Molecular, Instituto Carlos Chagas/Fiocruz-PR, Curitiba, Brazil
| |
Collapse
|
14
|
Abstract
Flaviviruses such as dengue, Japanese encephalitis, West Nile, Yellow Fever and Zika virus, cause viral hemorrhagic fever and encephalitis in humans. However, antiviral therapeutics to treat or prevent flavivirus infections are not yet available. Thus, there is pressing need to develop therapeutics and vaccines that target flavivirus infections. All flaviviruses carry a positive-sense single-stranded RNA genome, which encodes ten proteins; three structural proteins form the virus shell, and seven nonstructural (NS) proteins are involved in replication of the viral genome. While all NS proteins (NS1, NS2A, NS2B, NS3, NS4A, NS4B, and NS5) are part of a functional membrane-bound replication complex, enzymatic activities required for flaviviral replication reside in only two NS proteins, NS3 and NS5. NS3 functions as a protease, helicase, and triphosphatase, and NS5 as a capping enzyme, methyltransferase, and RNA-dependent RNA polymerase. In this chapter, we provide an overview of viral replication focusing on the structure and function of NS3 and NS5 replicases. We further describe strategies and examples of current efforts to identify potential flavivirus inhibitors against NS3 and NS5 enzymatic activities that can be developed as therapeutic agents to combat flavivirus infections.
Collapse
Affiliation(s)
- Ekaterina Knyazhanskaya
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, The University of Texas Medical Branch, Galveston, TX, United States
| | - Marc C Morais
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, The University of Texas Medical Branch, Galveston, TX, United States
| | - Kyung H Choi
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, The University of Texas Medical Branch, Galveston, TX, United States.
| |
Collapse
|
15
|
Morita E, Suzuki Y. Membrane-Associated Flavivirus Replication Complex-Its Organization and Regulation. Viruses 2021; 13:v13061060. [PMID: 34205058 PMCID: PMC8228428 DOI: 10.3390/v13061060] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 06/02/2021] [Accepted: 06/02/2021] [Indexed: 02/07/2023] Open
Abstract
Flavivirus consists of a large number of arthropod-borne viruses, many of which cause life-threatening diseases in humans. A characteristic feature of flavivirus infection is to induce the rearrangement of intracellular membrane structure in the cytoplasm. This unique membranous structure called replication organelle is considered as a microenvironment that provides factors required for the activity of the flaviviral replication complex. The replication organelle serves as a place to coordinate viral RNA amplification, protein translation, and virion assembly and also to protect the viral replication complex from the cellular immune defense system. In this review, we summarize the current understanding of how the formation and function of membrane-associated flaviviral replication organelle are regulated by cellular factors.
Collapse
Affiliation(s)
- Eiji Morita
- Department of Biochemistry and Molecular Biology, Faculty of Agriculture and Life Science, Hirosaki University, 3 Bunkyo-cho, Hirosaki-shi 036-8561, Japan
- Correspondence: (E.M.); (Y.S.); Tel.: +81-172-39-3586 (E.M.); +81-72-684-7367 (Y.S.)
| | - Youichi Suzuki
- Department of Microbiology and Infection Control, Faculty of Medicine, Osaka Medical and Pharmaceutical University, 2-7 Daigaku-machi, Takatsuki 569-8686, Japan
- Correspondence: (E.M.); (Y.S.); Tel.: +81-172-39-3586 (E.M.); +81-72-684-7367 (Y.S.)
| |
Collapse
|
16
|
Sutto-Ortiz P, Tcherniuk S, Ysebaert N, Abeywickrema P, Noël M, Decombe A, Debart F, Vasseur JJ, Canard B, Roymans D, Rigaux P, Eléouët JF, Decroly E. The methyltransferase domain of the Respiratory Syncytial Virus L protein catalyzes cap N7 and 2'-O-methylation. PLoS Pathog 2021; 17:e1009562. [PMID: 33956914 PMCID: PMC8130918 DOI: 10.1371/journal.ppat.1009562] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 05/18/2021] [Accepted: 04/15/2021] [Indexed: 12/15/2022] Open
Abstract
Respiratory syncytial virus (RSV) is a negative sense single-stranded RNA virus and one of the main causes of severe lower respiratory tract infections in infants and young children. RSV RNA replication/transcription and capping are ensured by the viral Large (L) protein. The L protein contains a polymerase domain associated with a polyribonucleotidyl transferase domain in its N-terminus, and a methyltransferase (MTase) domain followed by the C-terminal domain (CTD) enriched in basic amino acids at its C-terminus. The MTase-CTD of Mononegavirales forms a clamp to accommodate RNA that is subsequently methylated on the cap structure and depending on the virus, on internal positions. These enzymatic activities are essential for efficient viral mRNA translation into proteins, and to prevent the recognition of uncapped viral RNA by innate immunity sensors. In this work, we demonstrated that the MTase-CTD of RSV, as well as the full-length L protein in complex with phosphoprotein (P), catalyzes the N7- and 2’-O-methylation of the cap structure of a short RNA sequence that corresponds to the 5’ end of viral mRNA. Using different experimental systems, we showed that the RSV MTase-CTD methylates the cap structure with a preference for N7-methylation as first reaction. However, we did not observe cap-independent internal methylation, as recently evidenced for the Ebola virus MTase. We also found that at μM concentrations, sinefungin, a S-adenosylmethionine analogue, inhibits the MTase activity of the RSV L protein and of the MTase-CTD domain. Altogether, these results suggest that the RSV MTase domain specifically recognizes viral RNA decorated by a cap structure and catalyzes its methylation, which is required for translation and innate immune system subversion. Respiratory syncytial virus (RSV) is responsible of infant bronchiolitis and severe lower respiratory tract infections in infants and young children, and the leading cause of hospitalization in children under one year of age. However, we still lack a vaccine and therapeutics against this important pathogen. The main enzymatic activities involved in RSV propagation are embedded in the Large (L) protein that contains the polymerase domain and also all the activities required for RNA cap structure synthesis and methylation. These post-transcriptional RNA modifications play a key role in virus replication because cap N7-methylation is required for viral RNA translation into proteins, and 2’-O-methylation hides viral RNA from innate immunity detection. Viral methyltransferase (MTase) activities are now considered potential antiviral targets because their inhibition might limit the virus production and strengthen early virus detection by innate immunity sensors. In this work, we compared the enzymatic activities of the MTase expressed as a single domain or in the context of the full-length L protein. We demonstrated that the MTase protein catalyzes the specific methylation of the cap structure at both N7- and 2’-O-positions, and we obtained the proof of concept that a S-adenosylmethionine analogue can inhibit the MTase activity of the L protein.
Collapse
Affiliation(s)
| | - Sergey Tcherniuk
- Unité de Virologie et Immunologie Moléculaires, INRAE, Université Paris Saclay, Jouy en Josas, France
| | - Nina Ysebaert
- Janssen Infectious Diseases and Vaccines, Beerse, Belgium
| | | | - Mathieu Noël
- IBMM, Université de Montpellier, ENSCM, CNRS, UMR 5247, Montpellier, France
| | - Alice Decombe
- Aix Marseille Université, CNRS, AFMB UMR 7257, Marseille, France
| | - Françoise Debart
- IBMM, Université de Montpellier, ENSCM, CNRS, UMR 5247, Montpellier, France
| | | | - Bruno Canard
- Aix Marseille Université, CNRS, AFMB UMR 7257, Marseille, France
| | - Dirk Roymans
- Janssen Infectious Diseases and Vaccines, Beerse, Belgium
| | - Peter Rigaux
- Janssen Infectious Diseases and Vaccines, Beerse, Belgium
| | - Jean-François Eléouët
- Unité de Virologie et Immunologie Moléculaires, INRAE, Université Paris Saclay, Jouy en Josas, France
| | - Etienne Decroly
- Aix Marseille Université, CNRS, AFMB UMR 7257, Marseille, France
- * E-mail:
| |
Collapse
|
17
|
Structures of flavivirus RNA promoters suggest two binding modes with NS5 polymerase. Nat Commun 2021; 12:2530. [PMID: 33953197 PMCID: PMC8100141 DOI: 10.1038/s41467-021-22846-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 03/30/2021] [Indexed: 01/07/2023] Open
Abstract
Flaviviruses use a ~70 nucleotide stem-loop structure called stem-loop A (SLA) at the 5' end of the RNA genome as a promoter for RNA synthesis. Flaviviral polymerase NS5 specifically recognizes SLA to initiate RNA synthesis and methylate the 5' guanosine cap. We report the crystal structures of dengue (DENV) and Zika virus (ZIKV) SLAs. DENV and ZIKV SLAs differ in the relative orientations of their top stem-loop helices to bottom stems, but both form an intermolecular three-way junction with a neighboring SLA molecule. To understand how NS5 engages SLA, we determined the SLA-binding site on NS5 and modeled the NS5-SLA complex of DENV and ZIKV. Our results show that the gross conformational differences seen in DENV and ZIKV SLAs can be compensated by the differences in the domain arrangements in DENV and ZIKV NS5s. We describe two binding modes of SLA and NS5 and propose an SLA-mediated RNA synthesis mechanism.
Collapse
|
18
|
Ruggieri A, Helm M, Chatel-Chaix L. An epigenetic 'extreme makeover': the methylation of flaviviral RNA (and beyond). RNA Biol 2021; 18:696-708. [PMID: 33356825 DOI: 10.1080/15476286.2020.1868150] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Beyond their high clinical relevance worldwide, flaviviruses (comprising dengue and Zika viruses) are of particular interest to understand the spatiotemporal control of RNA metabolism. Indeed, their positive single-stranded viral RNA genome (vRNA) undergoes in the cytoplasm replication, translation and encapsidation, three steps of the flavivirus life cycle that are coordinated through a fine-tuned equilibrium. Over the last years, RNA methylation has emerged as a powerful mechanism to regulate messenger RNA metabolism at the posttranscriptional level. Not surprisingly, flaviviruses exploit RNA epigenetic strategies to control crucial steps of their replication cycle as well as to evade sensing by the innate immune system. This review summarizes the current knowledge about vRNA methylation events and their impacts on flavivirus replication and pathogenesis. We also address the important challenges that the field of epitranscriptomics faces in reliably and accurately identifying RNA methylation sites, which should be considered in future studies on viral RNA modifications.
Collapse
Affiliation(s)
- Alessia Ruggieri
- Department of Infectious Diseases, Molecular Virology, Centre for Integrative Infectious Disease Research University of Heidelberg, Heidelberg, Germany
| | - Mark Helm
- Johannes Gutenberg-Universität Mainz, Institute of Pharmaceutical and Biomedical Sciences, Mainz, Germany
| | - Laurent Chatel-Chaix
- Institut National de la Recherche Scientifique, Centre Armand-Frappier Santé Biotechnologie, Laval, Québec, Canada
| |
Collapse
|
19
|
Thames JE, Waters CD, Valle C, Bassetto M, Aouadi W, Martin B, Selisko B, Falat A, Coutard B, Brancale A, Canard B, Decroly E, Seley-Radtke KL. Synthesis and biological evaluation of novel flexible nucleoside analogues that inhibit flavivirus replication in vitro. Bioorg Med Chem 2020; 28:115713. [PMID: 33128910 PMCID: PMC7457965 DOI: 10.1016/j.bmc.2020.115713] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 08/09/2020] [Accepted: 08/11/2020] [Indexed: 11/18/2022]
Abstract
Flaviviruses, such as Dengue (DENV) and Zika (ZIKV) viruses, represent a severe health burden. There are currently no FDA-approved treatments, and vaccines against most flaviviruses are still lacking. We have developed several flexible analogues ("fleximers") of the FDA-approved nucleoside Acyclovir that exhibit activity against various RNA viruses, demonstrating their broad-spectrum potential. The current study reports activity against DENV and Yellow Fever Virus (YFV), particularly for compound 1. Studies to elucidate the mechanism of action suggest the flex-analogue triphosphates, especially 1-TP, inhibit DENV and ZIKV methyltransferases, and a secondary, albeit weak, effect on the DENV RNA-dependent RNA polymerase was observed at high concentrations. The results of these studies are reported herein.
Collapse
Affiliation(s)
- Joy E Thames
- Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, Baltimore, MD, USA
| | - Charles D Waters
- Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, Baltimore, MD, USA
| | - Coralie Valle
- AFMB-UMR7257, CNRS, Aix Marseille University, Marseille, France
| | - Marcella Bassetto
- Department of Chemistry, College of Science, Swansea University, Swansea, UK
| | - Wahiba Aouadi
- AFMB-UMR7257, CNRS, Aix Marseille University, Marseille, France
| | - Baptiste Martin
- AFMB-UMR7257, CNRS, Aix Marseille University, Marseille, France
| | - Barbara Selisko
- AFMB-UMR7257, CNRS, Aix Marseille University, Marseille, France
| | - Arissa Falat
- Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, Baltimore, MD, USA
| | - Bruno Coutard
- Unité des Virus Émergents (UVE: Aix-Marseille Univ - IRD 190 - Inserm 1207 - IHU Méditerranée Infection), Marseille, France
| | - Andrea Brancale
- School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff, UK
| | - Bruno Canard
- AFMB-UMR7257, CNRS, Aix Marseille University, Marseille, France
| | - Etienne Decroly
- AFMB-UMR7257, CNRS, Aix Marseille University, Marseille, France
| | - Katherine L Seley-Radtke
- Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, Baltimore, MD, USA.
| |
Collapse
|
20
|
Coggins SA, Mahboubi B, Schinazi RF, Kim B. Mechanistic cross-talk between DNA/RNA polymerase enzyme kinetics and nucleotide substrate availability in cells: Implications for polymerase inhibitor discovery. J Biol Chem 2020; 295:13432-13443. [PMID: 32737197 PMCID: PMC7521635 DOI: 10.1074/jbc.rev120.013746] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 07/31/2020] [Indexed: 01/01/2023] Open
Abstract
Enzyme kinetic analysis reveals a dynamic relationship between enzymes and their substrates. Overall enzyme activity can be controlled by both protein expression and various cellular regulatory systems. Interestingly, the availability and concentrations of intracellular substrates can constantly change, depending on conditions and cell types. Here, we review previously reported enzyme kinetic parameters of cellular and viral DNA and RNA polymerases with respect to cellular levels of their nucleotide substrates. This broad perspective exposes a remarkable co-evolution scenario of DNA polymerase enzyme kinetics with dNTP levels that can vastly change, depending on cell proliferation profiles. Similarly, RNA polymerases display much higher Km values than DNA polymerases, possibly due to millimolar range rNTP concentrations found in cells (compared with micromolar range dNTP levels). Polymerases are commonly targeted by nucleotide analog inhibitors for the treatments of various human diseases, such as cancers and viral pathogens. Because these inhibitors compete against natural cellular nucleotides, the efficacy of each inhibitor can be affected by varying cellular nucleotide levels in their target cells. Overall, both kinetic discrepancy between DNA and RNA polymerases and cellular concentration discrepancy between dNTPs and rNTPs present pharmacological and mechanistic considerations for therapeutic discovery.
Collapse
Affiliation(s)
- Si'Ana A Coggins
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia, USA
| | - Bijan Mahboubi
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia, USA
| | - Raymond F Schinazi
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia, USA
| | - Baek Kim
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia, USA; Center for Drug Discovery, Children's Healthcare of Atlanta, Atlanta, Georgia, USA.
| |
Collapse
|
21
|
Bujalowski PJ, Bujalowski W, Choi KH. Identification of the viral RNA promoter stem loop A (SLA)-binding site on Zika virus polymerase NS5. Sci Rep 2020; 10:13306. [PMID: 32764551 PMCID: PMC7413259 DOI: 10.1038/s41598-020-70094-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2019] [Accepted: 07/03/2020] [Indexed: 12/17/2022] Open
Abstract
Zika virus has recently emerged as an important human pathogen that has spread to more than 60 countries. Infection of a pregnant woman with Zika virus can cause severe brain malformations in the child such as microcephaly and other birth defects. Despite the medical importance of Zika virus infection, the mechanism of viral replication, a process commonly targeted by antiviral therapeutics, is not well understood. Stem-loop A (SLA), located in the 5' untranslated region of the viral genome, acts as a promotor for viral replication and thus is critical for recognition of the viral genome by the viral polymerase NS5. However, how NS5 engages SLA is not clear. We have quantitatively examined the intrinsic affinities between Zika virus SLA and NS5, and identified the SLA-binding site on NS5. Amino acid substitutions in the thumb subdomain of the RNA-dependent RNA polymerase (RdRp) and the methyltransferase (MTase) domain reduced SLA-binding affinity, indicating that they each are part of the SLA-binding site. Furthermore, stopped-flow kinetic analysis of Zika NS5-, RdRp- and MTase-SLA interactions identified distinct intermediates during NS5 and SLA complex formation. These data suggest a model for SLA recognition and the initiation of flaviviral replication by NS5.
Collapse
Affiliation(s)
- Paul J Bujalowski
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, The University of Texas Medical Branch, Galveston, TX, 77555, USA
| | - Wlodzimierz Bujalowski
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, The University of Texas Medical Branch, Galveston, TX, 77555, USA
| | - Kyung H Choi
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, The University of Texas Medical Branch, Galveston, TX, 77555, USA.
| |
Collapse
|
22
|
Chagas M, Rocha W, Moraes A. Dynamics and allostery of Zika virus non-structural protein 5 methyltransferase. J Biomol Struct Dyn 2020; 39:5526-5538. [DOI: 10.1080/07391102.2020.1792343] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Marcelo Chagas
- Departamento de Química, ICEx, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Willian Rocha
- Departamento de Química, ICEx, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Adolfo Moraes
- Departamento de Química, ICEx, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
- Department of NMR-based Structural Biology, Max-Planck Institute for Biophysical Chemistry, Göttingen, Germany
| |
Collapse
|
23
|
Abdullah AA, Lee YK, Chin SP, Lim SK, Lee VS, Othman R, Othman S, Rahman NA, Yusof R, Heh CH. Discovery of Dengue Virus Inhibitors. Curr Med Chem 2020; 27:4945-5036. [PMID: 30514185 DOI: 10.2174/0929867326666181204155336] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 11/11/2018] [Accepted: 11/22/2018] [Indexed: 11/22/2022]
Abstract
To date, there is still no approved anti-dengue agent to treat dengue infection in the market. Although the only licensed dengue vaccine, Dengvaxia is available, its protective efficacy against serotypes 1 and 2 of dengue virus was reported to be lower than serotypes 3 and 4. Moreover, according to WHO, the risk of being hospitalized and having severe dengue increased in seronegative individuals after they received Dengvaxia vaccination. Nevertheless, various studies had been carried out in search of dengue virus inhibitors. These studies focused on the structural (C, prM, E) and non-structural proteins (NS1, NS2A, NS2B, NS3, NS4A, NS4B and NS5) of dengue virus as well as host factors as drug targets. Hence, this article provides an overall up-to-date review of the discovery of dengue virus inhibitors that are only targeting the structural and non-structural viral proteins as drug targets.
Collapse
Affiliation(s)
- Adib Afandi Abdullah
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
| | - Yean Kee Lee
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
| | - Sek Peng Chin
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
| | - See Khai Lim
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
| | - Vannajan Sanghiran Lee
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
| | - Rozana Othman
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
| | - Shatrah Othman
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
| | - Noorsaadah Abdul Rahman
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
| | - Rohana Yusof
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
| | - Choon Han Heh
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
24
|
Abstract
Dengue virus (DENV) belongs to the family Flaviviridae, genus Flavivirus. It is a single-stranded positive-sense ribonucleic acid virus with 10,700 bases. The genus Flavivirus includes other arthropod borne viruses such as yellow fever virus, West Nile virus, Zika virus, tick-borne encephalitis virus. It infects ~50–200 million people annually, putting over 3.6 billion people living in tropical regions at risk and causing ~20,000 deaths annually. The expansion of dengue is attributed to factors such as the modern dynamics of climate change, globalization, travel, trade, socioeconomics, settlement, and also viral evolution. There are four antigenically different serotypes of DENV based on the differences in their viral structural and nonstructural proteins. DENV infection causes a spectrum of illness ranging from asymptomatic to dengue fever to severe dengue shock syndrome. Infection with one serotype confers lifelong immunity against that serotype, but heterologus infection leads to severe dengue hemorrhagic fever due to antibody-dependent enhancement. Diagnosis of dengue infections is based mainly on serological detection of either antigen in acute cases or antibodies in both acute and chronic infection. Viral detection and real-time PCR detection though helpful is not feasible in resource poor setup. Treatment of dengue depends on symptomatic management along with fluid resuscitation and may require platelet transfusion. Although vaccine development is in late stages of development, developing a single vaccine against four serotypes often causes serious challenges to researchers; hence, the main stay of prevention is vector control and management.
Collapse
|
25
|
Faheem M, Barbosa Lima JC, Jamal SB, Silva PA, Barbosa JARG. An insight into dengue virus proteins as potential drug/vaccine targets. Future Virol 2019. [DOI: 10.2217/fvl-2019-0107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Dengue virus (DENV) is an arbovirus that belongs to family flaviviridae. Its genome is composed of a single stranded RNA molecule that encodes a single polyprotein. The polyprotein is processed by viral and cellular proteases to generate ten viral proteins. There are four antigenically distinct serotypes of DENV (DENV1, DENV2, DENV3 and DENV4), which are genetically related. Although protein variability is a major problem in dengue treatment, the functional and structural studies of individual proteins are equally important in treatment development. The data accumulated on dengue proteins are significant to provide detailed understanding of viral infection, replication, host-immune evasion and pathogenesis. In this review, we summarized the detailed current knowledge about DENV proteins.
Collapse
Affiliation(s)
- Muhammad Faheem
- Laboratory of Biophysics, Department of Cellular Biology, University of Brasilia, Brasilia-DF 70910-900, Brazil
- Post-graduate program of Genomics Sciences & Biotechnology, Catholic University of Brasilia, Brasília-DF 70790-160, Brazil
| | - Jônatas Cunha Barbosa Lima
- Laboratory of Biophysics, Department of Cellular Biology, University of Brasilia, Brasilia-DF 70910-900, Brazil
| | - Syed Babar Jamal
- Department of Biological Sciences, National University of Medical Sciences, The Mall road, Rawalpindi, Punjab 46000, Pakistan
| | - Paula Andreia Silva
- Post-graduate program of Genomics Sciences & Biotechnology, Catholic University of Brasilia, Brasília-DF 70790-160, Brazil
| | - João Alexandre Ribeiro Gonçalves Barbosa
- Laboratory of Biophysics, Department of Cellular Biology, University of Brasilia, Brasilia-DF 70910-900, Brazil
- Post-graduate program of Genomics Sciences & Biotechnology, Catholic University of Brasilia, Brasília-DF 70790-160, Brazil
| |
Collapse
|
26
|
Rothan HA, Kumar M. Role of Endoplasmic Reticulum-Associated Proteins in Flavivirus Replication and Assembly Complexes. Pathogens 2019; 8:E148. [PMID: 31547236 PMCID: PMC6789530 DOI: 10.3390/pathogens8030148] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 09/09/2019] [Accepted: 09/11/2019] [Indexed: 01/29/2023] Open
Abstract
Flavivirus replication in host cells requires the formation of replication and assembly complexes on the cytoplasmic side of the endoplasmic reticulum (ER) membrane. These complexes consist of an ER membrane, viral proteins, and host proteins. Genome-wide investigations have identified a number of ER multiprotein complexes as vital factors for flavivirus replication. The detailed mechanisms of the role of ER complexes in flavivirus replication are still largely elusive. This review highlights the fact that the ER multiprotein complexes are crucial for the formation of flavivirus replication and assembly complexes, and the ER complexes could be considered as a target for developing successful broad-spectrum anti-flavivirus drugs.
Collapse
Affiliation(s)
- Hussin A Rothan
- Department of Biology, College of Arts and Sciences, Georgia State University, Atlanta, GA 30303, USA.
| | - Mukesh Kumar
- Department of Biology, College of Arts and Sciences, Georgia State University, Atlanta, GA 30303, USA.
| |
Collapse
|
27
|
Sobhia ME, Ghosh K, Singh A, Sul K, Singh M, Kumar R, Sandeep, Merugu S, Donempudi S. A Multi-Perspective Review on Dengue Research. Curr Drug Targets 2019; 20:1550-1562. [PMID: 31339068 DOI: 10.2174/1389450120666190724145937] [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: 04/24/2019] [Revised: 07/03/2019] [Accepted: 07/17/2019] [Indexed: 11/22/2022]
Abstract
Dengue fever is a disease which is caused by a family of viruses named Flaviviridae which are transmitted by female Aedes mosquitoes. Today, this is endemic in more than 100 nations in the World Health Organization's African, Americas, Eastern Mediterranean, South-East Asia and Western Pacific locales. The treatment of typical dengue is focused on relieving the symptoms and signs. Carica papaya is a very common plant whose leaf extract is used in the treatment of this disease. Despite extensive research on Dengue, not a single vaccine or anti-viral drug was available until 2016 (a partially effective Chimeric Yellow fever virus treated by DENV-Tetravalent Dengue Vaccine for dengue fever made by Sanofi Pasteur). This review highlights dengue fever's current situation and explains the importance of Natural chemical moieties like methionine-proline anilides, tetrapeptide aldehyde uncovered via Structure Activity Relationship studies. Also, we have reviewed the drug candidates currently in the clinical trials that have the potential to solve these issues. Important patents in the past 20 years have been outlined in this review. An in depth Protein Data Bank analysis of the different possible target proteins that can potentially have a major role in curing Dengue fever has been conducted.
Collapse
Affiliation(s)
- M Elizabeth Sobhia
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, Mohali, India
| | - Ketan Ghosh
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, Mohali, India
| | - Ajeet Singh
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, Mohali, India
| | - Komal Sul
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, Mohali, India
| | - Monica Singh
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, Mohali, India
| | - Ravi Kumar
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, Mohali, India
| | - Sandeep
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, Mohali, India
| | - Satti Merugu
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, Mohali, India
| | - Sunilchand Donempudi
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, Mohali, India
| |
Collapse
|
28
|
Ng IHW, Chan KWK, Tan MJA, Gwee CP, Smith KM, Jeffress SJ, Saw WG, Swarbrick CMD, Watanabe S, Jans DA, Grüber G, Forwood JK, Vasudevan SG. Zika Virus NS5 Forms Supramolecular Nuclear Bodies That Sequester Importin-α and Modulate the Host Immune and Pro-Inflammatory Response in Neuronal Cells. ACS Infect Dis 2019; 5:932-948. [PMID: 30848123 DOI: 10.1021/acsinfecdis.8b00373] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The Zika virus (ZIKV) epidemic in the Americas was alarming because of its link with microcephaly in neonates and Guillain-Barré syndrome in adults. The unusual pathologies induced by ZIKV infection and the knowledge that the flaviviral nonstructural protein 5 (NS5), the most conserved protein in the flavivirus proteome, can modulate the host immune response during ZIKV infection prompted us to investigate the subcellular localization of NS5 during ZIKV infection and explore its functional significance. A monopartite nuclear localization signal (NLS) sequence within ZIKV NS5 was predicted by the cNLS Mapper program, and we observed localization of ZIKV NS5 in the nucleus of infected cells by immunostaining with specific antibodies. Strikingly, ZIKV NS5 forms spherical shell-like nuclear bodies that exclude DNA. The putative monopartite NLS 390KRPR393 is necessary to direct FLAG-tagged NS5 to the nucleus as the NS5 390ARPA393 mutant protein accumulates in the cytoplasm. Furthermore, coimmunostaining experiments reveal that NS5 localizes with and sequesters importin-α, but not importin-β, in the observed nuclear bodies during virus infection. Structural and biochemical data demonstrate binding of ZIKV NS5 with importin-α and reveal important binding determinants required for their interaction and formation of complexes that give rise to the supramolecular nuclear bodies. Significantly, we demonstrate a neuronal-specific activation of the host immune response to ZIKV infection and a possible role of ZIKV NS5's nuclear localization toward this activation. This suggests that ZIKV pathogenesis may arise from a tissue-specific host response to ZIKV infection.
Collapse
Affiliation(s)
- Ivan H. W. Ng
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, 8 College Road, Singapore 169857
| | - Kitti Wing-Ki Chan
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, 8 College Road, Singapore 169857
- Department of Microbiology and Immunology, National University of Singapore, 5 Science Drive 2, Singapore 117545
| | - Min Jie Alvin Tan
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, 8 College Road, Singapore 169857
- Genome Institute of Singapore, Agency for Science & Technology Research (A*STAR), 60 Biopolis Street, Singapore 138672
| | - Chin Piaw Gwee
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, 8 College Road, Singapore 169857
| | - Kate M. Smith
- School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, New South Wales 2650, Australia
| | - Sarah J. Jeffress
- School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, New South Wales 2650, Australia
| | - Wuan-Geok Saw
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551
| | - Crystall M. D. Swarbrick
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, 8 College Road, Singapore 169857
| | - Satoru Watanabe
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, 8 College Road, Singapore 169857
| | - David A. Jans
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
| | - Gerhard Grüber
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551
| | - Jade K. Forwood
- School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, New South Wales 2650, Australia
| | - Subhash G. Vasudevan
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, 8 College Road, Singapore 169857
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
- Department of Microbiology and Immunology, National University of Singapore, 5 Science Drive 2, Singapore 117545
| |
Collapse
|
29
|
Kao YT, Lai MMC, Yu CY. How Dengue Virus Circumvents Innate Immunity. Front Immunol 2018; 9:2860. [PMID: 30564245 PMCID: PMC6288372 DOI: 10.3389/fimmu.2018.02860] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 11/20/2018] [Indexed: 12/24/2022] Open
Abstract
In the battle between a virus and its host, innate immunity serves as the first line of defense protecting the host against pathogens. The antiviral actions start with the recognition of pathogen-associated molecular patterns derived from the virus, then ultimately turning on particular transcription factors to generate antiviral interferons (IFNs) or proinflammatory cytokines via fine-tuned signaling cascades. With dengue virus (DENV) infection, its viral RNA is recognized by the host RNA sensors, mainly retinoic acid inducible gene-I (RIG-I)-like receptors (RLRs) and toll-like receptors. DENV infection also activates the cyclic GMP-AMP synthase–stimulator of interferon genes (cGAS–STING)-mediated DNA-sensing pathway despite the absence of a DNA stage in the DENV lifecycle. In the last decade, DENV has been considered a weak IFN-inducing pathogen with the evidence that DENV has evolved multiple strategies antagonizing the host IFN system. DENV passively escapes from innate immunity surveillance and also actively subverts the innate immune system at multiple steps. DENV targets both RNA-triggered RLR–mitochondrial antiviral signaling protein (RLR–MAVS) and DNA-triggered cGAS–STING signaling to reduce IFN production in infected cells. It also blocks IFN action by inhibiting IFN regulatory factor- and signal transducer and activator of transcription-mediated signaling. This review explores the current understanding of how DENV escapes the control of the innate immune system by modifying viral RNA and viral protein and by post-translational modification of cellular factors. The roles of the DNA-sensing pathway in DENV infection, and how mitochondrial dynamics participates in innate immunity are also discussed.
Collapse
Affiliation(s)
- Yu-Ting Kao
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Tainan, Taiwan
| | - Michael M C Lai
- Research Center for Emerging Viruses, China Medical University Hospital, Taichung, Taiwan.,Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Chia-Yi Yu
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Tainan, Taiwan
| |
Collapse
|
30
|
Liu W, Shi X, Gong P. A unique intra-molecular fidelity-modulating mechanism identified in a viral RNA-dependent RNA polymerase. Nucleic Acids Res 2018; 46:10840-10854. [PMID: 30239956 PMCID: PMC6237809 DOI: 10.1093/nar/gky848] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 09/11/2018] [Indexed: 01/07/2023] Open
Abstract
Typically not assisted by proofreading, the RNA-dependent RNA polymerases (RdRPs) encoded by the RNA viruses may need to independently control its fidelity to fulfill virus viability and fitness. However, the precise mechanism by which the RdRP maintains its optimal fidelity level remains largely elusive. By solving 2.1-2.5 Å resolution crystal structures of the classical swine fever virus (CSFV) NS5B, an RdRP with a unique naturally fused N-terminal domain (NTD), we identified high-resolution intra-molecular interactions between the NTD and the RdRP palm domain. In order to dissect possible regulatory functions of NTD, we designed mutations at residues Y471 and E472 to perturb key interactions at the NTD-RdRP interface. When crystallized, some of these NS5B interface mutants maintained the interface, while the others adopted an 'open' conformation that no longer retained the intra-molecular interactions. Data from multiple in vitro RdRP assays indicated that the perturbation of the NTD-RdRP interactions clearly reduced the fidelity level of the RNA synthesis, while the processivity of the NS5B elongation complex was not affected. Collectively, our work demonstrates an explicit and unique mode of polymerase fidelity modulation and provides a vivid example of co-evolution in multi-domain enzymes.
Collapse
Affiliation(s)
- Weichi Liu
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, China,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaoling Shi
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, China,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Peng Gong
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, China,To whom correspondence should be addressed. Tel: +86 27 87197578;
| |
Collapse
|
31
|
Martin B, Coutard B, Guez T, Paesen GC, Canard B, Debart F, Vasseur JJ, Grimes JM, Decroly E. The methyltransferase domain of the Sudan ebolavirus L protein specifically targets internal adenosines of RNA substrates, in addition to the cap structure. Nucleic Acids Res 2018; 46:7902-7912. [PMID: 30192980 PMCID: PMC6125687 DOI: 10.1093/nar/gky637] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 06/29/2018] [Accepted: 07/04/2018] [Indexed: 01/08/2023] Open
Abstract
Mononegaviruses, such as Ebola virus, encode an L (large) protein that bears all the catalytic activities for replication/transcription and RNA capping. The C-terminal conserved region VI (CRVI) of L protein contains a K-D-K-E catalytic tetrad typical for 2'O methyltransferases (MTase). In mononegaviruses, cap-MTase activities have been involved in the 2'O methylation and N7 methylation of the RNA cap structure. These activities play a critical role in the viral life cycle as N7 methylation ensures efficient viral mRNA translation and 2'O methylation hampers the detection of viral RNA by the host innate immunity. The functional characterization of the MTase+CTD domain of Sudan ebolavirus (SUDV) revealed cap-independent methyltransferase activities targeting internal adenosine residues. Besides this, the MTase+CTD also methylates, the N7 position of the cap guanosine and the 2'O position of the n1 guanosine provided that the RNA is sufficiently long. Altogether, these results suggest that the filovirus MTases evolved towards a dual activity with distinct substrate specificities. Whereas it has been well established that cap-dependent methylations promote protein translation and help to mimic host RNA, the characterization of an original cap-independent methylation opens new research opportunities to elucidate the role of RNA internal methylations in the viral replication.
Collapse
Affiliation(s)
- Baptiste Martin
- AFMB, CNRS, Aix-Marseille Université, UMR 7257, Case 925, 163 Avenue de Luminy, 13288 Marseille Cedex 09, France
| | - Bruno Coutard
- AFMB, CNRS, Aix-Marseille Université, UMR 7257, Case 925, 163 Avenue de Luminy, 13288 Marseille Cedex 09, France
| | - Théo Guez
- IBMM, University of Montpellier, CNRS, ENSCM, Montpellier, France
| | - Guido C Paesen
- Division of Structural Biology, Wellcome Centre for Human Genetics, Oxford OX3 7BN, UK
| | - Bruno Canard
- AFMB, CNRS, Aix-Marseille Université, UMR 7257, Case 925, 163 Avenue de Luminy, 13288 Marseille Cedex 09, France
| | - Françoise Debart
- IBMM, University of Montpellier, CNRS, ENSCM, Montpellier, France
| | | | - Jonathan M Grimes
- Division of Structural Biology, Wellcome Centre for Human Genetics, Oxford OX3 7BN, UK
- Diamond Light Source Limited, Harwell Science and Innovation Campus, Didcot OX11 0DE, UK
| | - Etienne Decroly
- AFMB, CNRS, Aix-Marseille Université, UMR 7257, Case 925, 163 Avenue de Luminy, 13288 Marseille Cedex 09, France
| |
Collapse
|
32
|
Sinigaglia A, Riccetti S, Trevisan M, Barzon L. In silico approaches to Zika virus drug discovery. Expert Opin Drug Discov 2018; 13:825-835. [PMID: 30160181 DOI: 10.1080/17460441.2018.1515909] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
INTRODUCTION After the WHO declared Zika virus (ZIKV) as a public health emergency of international concern, intense research for the development of vaccines and drugs has been undertaken, leading to the development of several candidates. Areas covered: This review discusses the developments achieved so far by computational methods in the discovery of candidate compounds targeting ZIKV proteins, i.e. the envelope and capsid structural proteins, the NS3 helicase/protease, and the NS5 methyltransferase/RNA-dependent RNA polymerase. Expert opinion: Research for effective drugs against ZIKV is still in a very early discovery phase. Notwithstanding the intense efforts for the development of new drugs and the identification of several promising candidates by using different approaches, including computational methods, so far only a few candidates have been experimentally tested. An important caveat of anti-flavivirus drug development is represented by the difficult of reproducing the in vivo microenvironment of the replication complex, which may lead to discrepancies between in vitro results and experimental evaluation in vivo. Moreover, anti-ZIKV drugs have the additional requirement of an excellent safety profile in pregnancy and ability to diffuse to different tissues, including the central nervous system, the testis, and the placenta.
Collapse
Affiliation(s)
| | - Silvia Riccetti
- a Department of Molecular Medicine , University of Padova , Padova , Italy
| | - Marta Trevisan
- a Department of Molecular Medicine , University of Padova , Padova , Italy
| | - Luisa Barzon
- a Department of Molecular Medicine , University of Padova , Padova , Italy
| |
Collapse
|
33
|
Full-Genome Characterization and Genetic Evolution of West African Isolates of Bagaza Virus. Viruses 2018; 10:v10040193. [PMID: 29652824 PMCID: PMC5923487 DOI: 10.3390/v10040193] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 03/12/2018] [Accepted: 03/30/2018] [Indexed: 01/26/2023] Open
Abstract
Bagaza virus is a mosquito-borne flavivirus, first isolated in 1966 in Central African Republic. It has currently been identified in mosquito pools collected in the field in West and Central Africa. Emergence in wild birds in Europe and serological evidence in encephalitis patients in India raise questions on its genetic evolution and the diversity of isolates circulating in Africa. To better understand genetic diversity and evolution of Bagaza virus, we describe the full-genome characterization of 11 West African isolates, sampled from 1988 to 2014. Parameters such as genetic distances, N-glycosylation patterns, recombination events, selective pressures, and its codon adaptation to human genes are assessed. Our study is noteworthy for the observation of N-glycosylation and recombination in Bagaza virus and provides insight into its Indian origin from the 13th century. Interestingly, evidence of Bagaza virus codon adaptation to human house-keeping genes is also observed to be higher than those of other flaviviruses well known in human infections. Genetic variations on genome of West African Bagaza virus could play an important role in generating diversity and may promote Bagaza virus adaptation to other vertebrates and become an important threat in human health.
Collapse
|
34
|
Strand-like structures and the nonstructural proteins 5, 3 and 1 are present in the nucleus of mosquito cells infected with dengue virus. Virology 2018; 515:74-80. [DOI: 10.1016/j.virol.2017.12.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 12/13/2017] [Accepted: 12/14/2017] [Indexed: 12/18/2022]
|
35
|
The Transactions of NS3 and NS5 in Flaviviral RNA Replication. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1062:147-163. [PMID: 29845531 DOI: 10.1007/978-981-10-8727-1_11] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Dengue virus (DENV) replication occurs in virus-induced vesicles that contain the replication complex (RC) where viral RNA, viral proteins and host proteins participate in RNA-RNA, RNA-protein and protein-protein interactions to ensure viral genome synthesis. However, the details of the multitude of interactions involved in the biogenesis of the infectious virion are not fully understood. In this review, we will focus on the interaction between non-structural (NS) proteins NS3 and NS5, as well as their interactions with viral RNA and briefly also the interaction of NS5 with the host nuclear transport receptor protein importin-α. The multifunctional NS3 protease/helicase and NS5 methyltransferase (MTase)/RNA-dependent RNA polymerase (RdRp) contain all the enzymatic activities required to synthesize the viral RNA genome. The success stories of drug discovery and development with Hepatitis C virus (HCV), a member of the Flaviviridae family, has led to the view that DENV NS3 and NS5 may be attractive antiviral drug targets. However, more than 10 years of intensive research effort by Novatis has revealed that they are not "low hanging fruits" and therefore, the search for potent directly acting antivirals (DAAs) remains a pipeline goal for several medium to large drug discovery enterprises. The effort to discover DAAs for DENV has been boosted by the epidemic outbreak of the closely related flavivirus member - Zika virus (ZIKV). Because the viral RNA replication occurs within a molecular machine that is composed several viral and host proteins, much interest has turned to characterising functionally essential protein-protein interactions in order to identify potential allosteric inhibitor binding sites within the RC.
Collapse
|
36
|
Chatrin C, Talapatra SK, Canard B, Kozielski F. The structure of the binary methyltransferase-SAH complex from Zika virus reveals a novel conformation for the mechanism of mRNA capping. Oncotarget 2017; 9:3160-3171. [PMID: 29423037 PMCID: PMC5790454 DOI: 10.18632/oncotarget.23223] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 11/15/2017] [Indexed: 11/25/2022] Open
Abstract
Zika virus, a flavivirus like Dengue and West Nile viruses, poses a significant risk as a pathogen in the category of emerging infectious diseases. Zika infections typically cause nonspecific, mild symptoms, but can also manifest as a neurological disorder like Guillain-Barré syndrome. Infection in pregnant women is linked to microcephaly in newborn infants. The methyltransferase domain of the non-structural protein 5 is responsible for two sequential methylations of the 5′-RNA cap. This is crucial for genome stability, efficient translation, and escape from the host immune response. Here we present the crystal structures of the Zika methyltransferase domain in complex with the methyl-donor SAM and its by-product SAH. The methyltransferase-SAH binary complex presents a new conformation of a “closed” or “obstructed” state that would restrict the binding of new RNA for capping. The combination and comparison of our new structures with recently published Zika methyltransferase structures provide a first glimpse into the structural mechanism of Zika virus mRNA capping.
Collapse
Affiliation(s)
- Chatrin Chatrin
- Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, WC1N 1AX, London, United Kingdom
| | - Sandeep K Talapatra
- Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, WC1N 1AX, London, United Kingdom
| | - Bruno Canard
- CNRS, Aix Marseille University, AFMB UMR7257, Marseille, France
| | - Frank Kozielski
- Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, WC1N 1AX, London, United Kingdom
| |
Collapse
|
37
|
Zhou H, Wang F, Wang H, Chen C, Zhang T, Han X, Wang D, Chen C, Wu C, Xie W, Wang Z, Zhang L, Wang L, Yang H. The conformational changes of Zika virus methyltransferase upon converting SAM to SAH. Oncotarget 2017; 8:14830-14834. [PMID: 28122329 PMCID: PMC5362447 DOI: 10.18632/oncotarget.14780] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 01/11/2017] [Indexed: 01/09/2023] Open
Abstract
An outbreak of Zika virus (ZIKV) infection has been reported in South and Central America and the Caribbean. Neonatal microcephaly potentially associated with ZIKV infection has already caused a public health emergency of international concern. Currently, there are no clinically effective vaccines or antiviral drugs available to treat ZIKV infection. The methyltransferase domain (MTase) of ZIKV nonstructural protein 5 (NS5) can sequentially methylate guanine N-7 and ribose 2'-O to form m7NGpppA2'Om cap structure in the new RNA transcripts. This methylation step is crucial for ZIKV replication cycle and evading the host immune system, making it a target for drug design. Here, we present the 1.76 Å crystal structure of ZIKV MTase in complex with the byproduct SAH, providing insight into the elegant methylation process, which will benefit the following antiviral drug development.
Collapse
Affiliation(s)
- Han Zhou
- School of Life Sciences, Tianjin University, Tianjin 300072, China.,Tianjin International Joint Academy of Biotechnology and Medicine, Tianjin 300457, China
| | - Fenghua Wang
- School of Life Sciences, Tianjin University, Tianjin 300072, China
| | - Haofeng Wang
- School of Life Sciences, Tianjin University, Tianjin 300072, China
| | - Cheng Chen
- School of Life Sciences, Tianjin University, Tianjin 300072, China
| | - Tianqing Zhang
- School of Life Sciences, Tianjin University, Tianjin 300072, China
| | - Xu Han
- School of Life Sciences, Tianjin University, Tianjin 300072, China
| | - Deping Wang
- School of Life Sciences, Tianjin University, Tianjin 300072, China
| | - Chen Chen
- School of Life Sciences, Tianjin University, Tianjin 300072, China
| | - Chen Wu
- School of Life Sciences, Tianjin University, Tianjin 300072, China
| | - Wei Xie
- School of Life Sciences, Tianjin University, Tianjin 300072, China
| | - Zefang Wang
- School of Life Sciences, Tianjin University, Tianjin 300072, China
| | - Lei Zhang
- School of Life Sciences, Tianjin University, Tianjin 300072, China
| | - Lanfeng Wang
- Key Laboratory of Molecular Virology and Immunology, Institute Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai 200031, China
| | - Haitao Yang
- School of Life Sciences, Tianjin University, Tianjin 300072, China.,Tianjin International Joint Academy of Biotechnology and Medicine, Tianjin 300457, China
| |
Collapse
|
38
|
Brand C, Bisaillon M, Geiss BJ. Organization of the Flavivirus RNA replicase complex. WILEY INTERDISCIPLINARY REVIEWS-RNA 2017; 8. [PMID: 28815931 DOI: 10.1002/wrna.1437] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 07/09/2017] [Accepted: 07/13/2017] [Indexed: 12/20/2022]
Abstract
Flaviviruses, such as dengue, Japanese encephalitis, West Nile, yellow fever, and Zika viruses, are serious human pathogens that cause significant morbidity and mortality globally each year. Flaviviruses are single-stranded, positive-sense RNA viruses, and encode two multidomain proteins, NS3 and NS5, that possess all enzymatic activities required for genome replication and capping. NS3 and NS5 interact within virus-induced replication compartments to form the RNA genome replicase complex. Although the individual enzymatic activities of both proteins have been extensively studied and are well characterized, there are still gaps in our understanding of how they interact to efficiently coordinate their respective activities during positive-strand RNA synthesis and capping. Here, we discuss what is known about the structures and functions of the NS3 and NS5 proteins and propose a preliminary NS3:NS5:RNA interaction model based on a large body of literature about how the viral enzymes function, physical restraints between NS3 and NS5, as well as critical steps in the replication process. WIREs RNA 2017, 8:e1437. doi: 10.1002/wrna.1437 For further resources related to this article, please visit the WIREs website.
Collapse
Affiliation(s)
- Carolin Brand
- Département de Biochimie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Martin Bisaillon
- Département de Biochimie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Brian J Geiss
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA.,School of Biomedical Engineering, Colorado State University, Fort Collins, CO, USA
| |
Collapse
|
39
|
Boldescu V, Behnam MAM, Vasilakis N, Klein CD. Broad-spectrum agents for flaviviral infections: dengue, Zika and beyond. Nat Rev Drug Discov 2017; 16:565-586. [PMID: 28473729 PMCID: PMC5925760 DOI: 10.1038/nrd.2017.33] [Citation(s) in RCA: 198] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Infections with flaviviruses, such as dengue, West Nile virus and the recently re-emerging Zika virus, are an increasing and probably lasting global risk. This Review summarizes and comments on the opportunities for broad-spectrum agents that are active against multiple flaviviruses. Broad-spectrum activity is particularly desirable to prepare for the next flaviviral epidemic, which could emerge from as-yet unknown or neglected viruses. Potential molecular targets for broad-spectrum antiflaviviral compounds include viral proteins, such as the viral protease or polymerase, and host targets that are exploited by these viruses during entry and replication, including α-glucosidase and proteins involved in nucleoside biosynthesis. Numerous compounds with broad-spectrum antiviral activity have already been identified by target-specific or phenotypic assays. For other compounds, broad-spectrum activity can be anticipated because of their mode of action and molecular targets.
Collapse
Affiliation(s)
- Veaceslav Boldescu
- Medicinal Chemistry, Institute of Pharmacy and Molecular Biotechnology IPMB, Heidelberg University, Im Neuenheimer Feld 364, 69120 Heidelberg, Germany
- Laboratory of Organic Synthesis and Biopharmaceuticals, Institute of Chemistry of the Academy of Sciences of Moldova, Academiei 3, 2028 Chisinau, Moldova
| | - Mira A. M. Behnam
- Medicinal Chemistry, Institute of Pharmacy and Molecular Biotechnology IPMB, Heidelberg University, Im Neuenheimer Feld 364, 69120 Heidelberg, Germany
| | - Nikos Vasilakis
- Dept. of Pathology and Center for Biodefense and Emerging Infectious Diseases, Center for Tropical Diseases and Institute for Human Infections and Immunity, 2.138D Keiller Bldg, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555–0609, USA
| | - Christian D. Klein
- Medicinal Chemistry, Institute of Pharmacy and Molecular Biotechnology IPMB, Heidelberg University, Im Neuenheimer Feld 364, 69120 Heidelberg, Germany
| |
Collapse
|
40
|
Tambunan USF, Nasution MAF, Azhima F, Parikesit AA, Toepak EP, Idrus S, Kerami D. Modification of S-Adenosyl-l-Homocysteine as Inhibitor of Nonstructural Protein 5 Methyltransferase Dengue Virus Through Molecular Docking and Molecular Dynamics Simulation. Drug Target Insights 2017; 11:1177392817701726. [PMID: 28469408 PMCID: PMC5404899 DOI: 10.1177/1177392817701726] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 03/01/2017] [Indexed: 01/01/2023] Open
Abstract
Dengue fever is still a major threat worldwide, approximately threatening two-fifths of the world's population in tropical and subtropical countries. Nonstructural protein 5 (NS5) methyltransferase enzyme plays a vital role in the process of messenger RNA capping of dengue by transferring methyl groups from S-adenosyl-l-methionine to N7 atom of the guanine bases of RNA and the RNA ribose group of 2'OH, resulting in S-adenosyl-l-homocysteine (SAH). The modification of SAH compound was screened using molecular docking and molecular dynamics simulation, along with computational ADME-Tox (absorption, distribution, metabolism, excretion, and toxicity) test. The 2 simulations were performed using Molecular Operating Environment (MOE) 2008.10 software, whereas the ADME-Tox test was performed using various software. The modification of SAH compound was done using several functional groups that possess different polarities and properties, resulting in 3460 ligands to be docked. After conducting docking simulation, we earned 3 best ligands (SAH-M331, SAH-M2696, and SAH-M1356) based on ΔGbinding and molecular interactions, which show better results than the standard ligands. Moreover, the results of molecular dynamics simulation show that the best ligands are still able to maintain the active site residue interaction with the binding site until the end of the simulation. After a series of molecular docking and molecular dynamics simulation were performed, we concluded that SAH-M1356 ligand is the most potential SAH-based compound to inhibit NS5 methyltransferase enzyme for treating dengue fever.
Collapse
Affiliation(s)
- Usman Sumo Friend Tambunan
- Bioinformatics Research Group, Department of Chemistry, Faculty of Mathematics and Natural Science, University of Indonesia, Depok, Indonesia
| | | | - Fauziah Azhima
- Bioinformatics Research Group, Department of Chemistry, Faculty of Mathematics and Natural Science, University of Indonesia, Depok, Indonesia
| | - Arli Aditya Parikesit
- Bioinformatics Research Group, Department of Chemistry, Faculty of Mathematics and Natural Science, University of Indonesia, Depok, Indonesia
| | - Erwin Prasetya Toepak
- Bioinformatics Research Group, Department of Chemistry, Faculty of Mathematics and Natural Science, University of Indonesia, Depok, Indonesia
| | - Syarifuddin Idrus
- Industrial Standardization Laboratory, Ministry of Industrial Affair, Ambon, Indonesia
| | - Djati Kerami
- Mathematics Computation Research Group, Department of Mathematics, Faculty of Mathematics and Natural Science, University of Indonesia, Depok, Indonesia
| |
Collapse
|
41
|
Oliveira AFCDS, Teixeira RR, Oliveira ASD, Souza APMD, Silva MLD, Paula SOD. Potential Antivirals: Natural Products Targeting Replication Enzymes of Dengue and Chikungunya Viruses. Molecules 2017; 22:E505. [PMID: 28327521 PMCID: PMC6155337 DOI: 10.3390/molecules22030505] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 03/09/2017] [Accepted: 03/17/2017] [Indexed: 11/16/2022] Open
Abstract
Dengue virus (DENV) and chikungunya virus (CHIKV) are reemergent arboviruses that are transmitted by mosquitoes of the Aedes genus. During the last several decades, these viruses have been responsible for millions of cases of infection and thousands of deaths worldwide. Therefore, several investigations were conducted over the past few years to find antiviral compounds for the treatment of DENV and CHIKV infections. One attractive strategy is the screening of compounds that target enzymes involved in the replication of both DENV and CHIKV. In this review, we describe advances in the evaluation of natural products targeting the enzymes involved in the replication of these viruses.
Collapse
Affiliation(s)
- Ana Flávia Costa da Silveira Oliveira
- Departamento de Biologia Geral, Universidade Federal de Viçosa, Av. P.H. Rolfs, S/N, 36570-900 Viçosa, MG, Brazil.
- Instituto Federal de Educação, Ciência e Tecnologia do Norte de Minas, 39900-000 Almenara, MG, Brazil.
| | - Róbson Ricardo Teixeira
- Departamento de Química, Universidade Federal de Viçosa, Av. P.H. Rolfs, S/N, 36570-900 Viçosa, MG, Brazil.
| | - André Silva de Oliveira
- Departamento de Biologia Geral, Universidade Federal de Viçosa, Av. P.H. Rolfs, S/N, 36570-900 Viçosa, MG, Brazil.
- Instituto Federal de Educação, Ciência e Tecnologia do Norte de Minas, 39900-000 Almenara, MG, Brazil.
| | - Ana Paula Martins de Souza
- Departamento de Química, Universidade Federal de Viçosa, Av. P.H. Rolfs, S/N, 36570-900 Viçosa, MG, Brazil.
| | - Milene Lopes da Silva
- Departamento de Química, Universidade Federal de Viçosa, Av. P.H. Rolfs, S/N, 36570-900 Viçosa, MG, Brazil.
| | - Sérgio Oliveira de Paula
- Departamento de Biologia Geral, Universidade Federal de Viçosa, Av. P.H. Rolfs, S/N, 36570-900 Viçosa, MG, Brazil.
| |
Collapse
|
42
|
Non-Canonical Roles of Dengue Virus Non-Structural Proteins. Viruses 2017; 9:v9030042. [PMID: 28335410 PMCID: PMC5371797 DOI: 10.3390/v9030042] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 03/06/2017] [Accepted: 03/08/2017] [Indexed: 12/15/2022] Open
Abstract
The Flaviviridae family comprises a number of human pathogens, which, although sharing structural and functional features, cause diseases with very different outcomes. This can be explained by the plurality of functions exerted by the few proteins coded by viral genomes, with some of these functions shared among members of a same family, but others being unique for each virus species. These non-canonical functions probably have evolved independently and may serve as the base to the development of specific therapies for each of those diseases. Here it is discussed what is currently known about the non-canonical roles of dengue virus (DENV) non-structural proteins (NSPs), which may account for some of the effects specifically observed in DENV infection, but not in other members of the Flaviviridae family. This review explores how DENV NSPs contributes to the physiopathology of dengue, evasion from host immunity, metabolic changes, and redistribution of cellular components during infection.
Collapse
|
43
|
Duan W, Song H, Wang H, Chai Y, Su C, Qi J, Shi Y, Gao GF. The crystal structure of Zika virus NS5 reveals conserved drug targets. EMBO J 2017; 36:919-933. [PMID: 28254839 DOI: 10.15252/embj.201696241] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2016] [Revised: 01/16/2017] [Accepted: 02/02/2017] [Indexed: 12/31/2022] Open
Abstract
Zika virus (ZIKV) has emerged as major health concern, as ZIKV infection has been shown to be associated with microcephaly, severe neurological disease and possibly male sterility. As the largest protein component within the ZIKV replication complex, NS5 plays key roles in the life cycle and survival of the virus through its N-terminal methyltransferase (MTase) and C-terminal RNA-dependent RNA polymerase (RdRp) domains. Here, we present the crystal structures of ZIKV NS5 MTase in complex with an RNA cap analogue (m7GpppA) and the free NS5 RdRp. We have identified the conserved features of ZIKV NS5 MTase and RdRp structures that could lead to development of current antiviral inhibitors being used against flaviviruses, including dengue virus and West Nile virus, to treat ZIKV infection. These results should inform and accelerate the structure-based design of antiviral compounds against ZIKV.
Collapse
Affiliation(s)
- Wenqian Duan
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.,Savaid Medical School, University of Chinese Academy of Sciences, Beijing, China
| | - Hao Song
- Research Network of Immunity and Health (RNIH), Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, China
| | - Haiyuan Wang
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.,College of Animal Sciences and Technology, Guangxi University, Nanning, China
| | - Yan Chai
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Chao Su
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.,College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Jianxun Qi
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Yi Shi
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China .,Savaid Medical School, University of Chinese Academy of Sciences, Beijing, China.,Research Network of Immunity and Health (RNIH), Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, China.,Center for Influenza Research and Early-warning (CASCIRE), Chinese Academy of Sciences, Beijing, China.,Shenzhen Key Laboratory of Pathogen and Immunity, Shenzhen Third People's Hospital, Shenzhen, China
| | - George F Gao
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China .,Savaid Medical School, University of Chinese Academy of Sciences, Beijing, China.,Research Network of Immunity and Health (RNIH), Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, China.,Center for Influenza Research and Early-warning (CASCIRE), Chinese Academy of Sciences, Beijing, China.,Shenzhen Key Laboratory of Pathogen and Immunity, Shenzhen Third People's Hospital, Shenzhen, China.,National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention (China CDC), Beijing, China
| |
Collapse
|
44
|
Zika Virus Methyltransferase: Structure and Functions for Drug Design Perspectives. J Virol 2017; 91:JVI.02202-16. [PMID: 28031359 DOI: 10.1128/jvi.02202-16] [Citation(s) in RCA: 101] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 12/16/2016] [Indexed: 12/21/2022] Open
Abstract
The Flavivirus Zika virus (ZIKV) is the causal agent of neurological disorders like microcephaly in newborns or Guillain-Barre syndrome. Its NS5 protein embeds a methyltransferase (MTase) domain involved in the formation of the viral mRNA cap. We investigated the structural and functional properties of the ZIKV MTase. We show that the ZIKV MTase can methylate RNA cap structures at the N-7 position of the cap, and at the 2'-O position on the ribose of the first nucleotide, yielding a cap-1 structure. In addition, the ZIKV MTase methylates the ribose 2'-O position of internal adenosines of RNA substrates. The crystal structure of the ZIKV MTase determined at a 2.01-Å resolution reveals a crystallographic homodimer. One chain is bound to the methyl donor (S-adenosyl-l-methionine [SAM]) and shows a high structural similarity to the dengue virus (DENV) MTase. The second chain lacks SAM and displays conformational changes in the αX α-helix contributing to the SAM and RNA binding. These conformational modifications reveal a possible molecular mechanism of the enzymatic turnover involving a conserved Ser/Arg motif. In the second chain, the SAM binding site accommodates a sulfate close to a glycerol that could serve as a basis for structure-based drug design. In addition, compounds known to inhibit the DENV MTase show similar inhibition potency on the ZIKV MTase. Altogether these results contribute to a better understanding of the ZIKV MTase, a central player in viral replication and host innate immune response, and lay the basis for the development of potential antiviral drugs.IMPORTANCE The Zika virus (ZIKV) is associated with microcephaly in newborns, and other neurological disorders such as Guillain-Barre syndrome. It is urgent to develop antiviral strategies inhibiting the viral replication. The ZIKV NS5 embeds a methyltransferase involved in the viral mRNA capping process, which is essential for viral replication and control of virus detection by innate immune mechanisms. We demonstrate that the ZIKV methyltransferase methylates the mRNA cap and adenosines located in RNA sequences. The structure of ZIKV methyltransferase shows high structural similarities to the dengue virus methyltransferase, but conformational specificities highlight the role of a conserved Ser/Arg motif, which participates in RNA and SAM recognition during the reaction turnover. In addition, the SAM binding site accommodates a sulfate and a glycerol, offering structural information to initiate structure-based drug design. Altogether, these results contribute to a better understanding of the Flavivirus methyltransferases, which are central players in the virus replication.
Collapse
|
45
|
Lu G, Gong P. A structural view of the RNA-dependent RNA polymerases from the Flavivirus genus. Virus Res 2017; 234:34-43. [PMID: 28131854 DOI: 10.1016/j.virusres.2017.01.020] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 01/15/2017] [Accepted: 01/22/2017] [Indexed: 12/17/2022]
Abstract
The RNA-dependent RNA polymerase (RdRP) from the Flavivirus genus is naturally fused to a methyltransferase (MTase), and the full-length protein is named nonstructural protein 5 (NS5). Similar to polymerases from other RNA viruses, the flavivirus RdRP has an encircled human right hand architecture with palm, fingers, and thumb domains surrounding its polymerase active site. In contrast to primer-dependent RdRPs that have a spacious front channel to accommodate the template-product RNA duplex, the flavivirus RdRP has a priming element as a thumb domain insertion, partially occupying the front channel to facilitate the de novo initiation process. Seven catalytic motifs A through G have been identified for all viral RdRPs and have highly homologous spatial arrangement around the active site despite low sequence conservation in several motifs if considering all viral families, forming an important basis to the understandings of the common features for viral RdRPs. In the two different global conformations identified in full-length crystal structures of Japanese encephalitis virus (JEV) and Dengue virus (DENV) NS5 proteins, the MTase approaches the RdRP consistently from the backside but its orientation and the interaction details with the RdRP are drastically different. Further investigations are required to clarify the conservation, functional relevance, and relationship of these conformations. Remaining challenges with respect to flavivirus RdRP structure are also discussed.
Collapse
Affiliation(s)
- Guoliang Lu
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, No. 44 Xiao Hong Shan, Wuhan, Hubei 430071, China
| | - Peng Gong
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, No. 44 Xiao Hong Shan, Wuhan, Hubei 430071, China.
| |
Collapse
|
46
|
Benmansour F, Trist I, Coutard B, Decroly E, Querat G, Brancale A, Barral K. Discovery of novel dengue virus NS5 methyltransferase non-nucleoside inhibitors by fragment-based drug design. Eur J Med Chem 2017; 125:865-880. [DOI: 10.1016/j.ejmech.2016.10.007] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 10/03/2016] [Accepted: 10/04/2016] [Indexed: 10/20/2022]
|
47
|
Bullard-Feibelman KM, Govero J, Zhu Z, Salazar V, Veselinovic M, Diamond MS, Geiss BJ. The FDA-approved drug sofosbuvir inhibits Zika virus infection. Antiviral Res 2016; 137:134-140. [PMID: 27902933 DOI: 10.1016/j.antiviral.2016.11.023] [Citation(s) in RCA: 178] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 11/24/2016] [Accepted: 11/24/2016] [Indexed: 01/08/2023]
Abstract
The rapidly expanding Zika virus (ZIKV) epidemic has affected thousands of individuals with severe cases causing Guillain-Barré syndrome, congenital malformations, and microcephaly. Currently, there is no available vaccine or therapy to prevent or treat ZIKV infection. We evaluated whether sofosbuvir, an FDA-approved nucleotide polymerase inhibitor for the distantly related hepatitis C virus, could have antiviral activity against ZIKV infection. Cell culture studies established that sofosbuvir efficiently inhibits replication and infection of several ZIKV strains in multiple human tumor cell lines and isolated human fetal-derived neuronal stem cells. Moreover, oral treatment with sofosbuvir protected against ZIKV-induced death in mice. These results suggest that sofosbuvir may be a candidate for further evaluation as a therapy against ZIKV infection in humans.
Collapse
Affiliation(s)
| | - Jennifer Govero
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO, USA
| | - Zhe Zhu
- Department of Stem Cell Biology and Regenerative Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Vanessa Salazar
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO, USA
| | - Milena Veselinovic
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Michael S Diamond
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO, USA; Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO, USA; Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, MO, USA; The Center for Human Immunology and Immunotherapy Programs, Washington University School of Medicine, Saint Louis, MO, USA
| | - Brian J Geiss
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA; School of Biomedical Engineering, Colorado State University, Fort Collins, CO, USA.
| |
Collapse
|
48
|
Zhang C, Feng T, Cheng J, Li Y, Yin X, Zeng W, Jin X, Li Y, Guo F, Jin T. Structure of the NS5 methyltransferase from Zika virus and implications in inhibitor design. Biochem Biophys Res Commun 2016; 492:624-630. [PMID: 27866982 DOI: 10.1016/j.bbrc.2016.11.098] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 11/16/2016] [Indexed: 11/28/2022]
Abstract
Recent outbreak of flavivirus Zika virus (ZIKV) in America has urged the basic as well as translational studies of this important human pathogen. The nonstructural protein 5 (NS5) of the flavivirus has an N-terminal methyltransferase (MTase) domain that plays critical roles in viral RNA genome capping. The null mutant of NS5 MTase is lethal for virus. Therefore, NS5 is a potential drug target for the treatment of Zika virus infection. In this study, we determined crystal structures of the ZIKV MTase in complex with GTP and RNA cap analogue 7meGpppA. Structural analyses revealed highly conserved GTP/cap-binding pocket and S-adenosylmethionine (SAM)-binding pocket. Two conformations of the second base of the cap were identified, which suggests the flexibility of RNA conformation. In addition, the ligand-binding pockets identified a continuous region of hotspots suitable for drug design. Docking calculation shows that the Dengue virus inhibitor compound 10 may bind to the ZIKV MTase.
Collapse
Affiliation(s)
- Caiying Zhang
- Laboratory of Structural Immunology, CAS Key Laboratory of Innate Immunity and Chronic Disease, CAS Center for Excellence in Molecular Cell Science, School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, Anhui, 230027, China
| | - Tingting Feng
- Laboratory of Structural Immunology, CAS Key Laboratory of Innate Immunity and Chronic Disease, CAS Center for Excellence in Molecular Cell Science, School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, Anhui, 230027, China
| | - Jinbo Cheng
- Laboratory of Structural Immunology, CAS Key Laboratory of Innate Immunity and Chronic Disease, CAS Center for Excellence in Molecular Cell Science, School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, Anhui, 230027, China
| | - Yajuan Li
- Laboratory of Structural Immunology, CAS Key Laboratory of Innate Immunity and Chronic Disease, CAS Center for Excellence in Molecular Cell Science, School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, Anhui, 230027, China
| | - Xueying Yin
- Laboratory of Structural Immunology, CAS Key Laboratory of Innate Immunity and Chronic Disease, CAS Center for Excellence in Molecular Cell Science, School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, Anhui, 230027, China
| | - Weihong Zeng
- Laboratory of Structural Immunology, CAS Key Laboratory of Innate Immunity and Chronic Disease, CAS Center for Excellence in Molecular Cell Science, School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, Anhui, 230027, China
| | - Xiangyu Jin
- Laboratory of Structural Immunology, CAS Key Laboratory of Innate Immunity and Chronic Disease, CAS Center for Excellence in Molecular Cell Science, School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, Anhui, 230027, China
| | - Yuelong Li
- Laboratory of Structural Immunology, CAS Key Laboratory of Innate Immunity and Chronic Disease, CAS Center for Excellence in Molecular Cell Science, School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, Anhui, 230027, China
| | - Feng Guo
- School of Medicine, Stanford University, Stanford, CA 94305, USA
| | - Tengchuan Jin
- Laboratory of Structural Immunology, CAS Key Laboratory of Innate Immunity and Chronic Disease, CAS Center for Excellence in Molecular Cell Science, School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, Anhui, 230027, China.
| |
Collapse
|
49
|
Tay MYF, Smith K, Ng IHW, Chan KWK, Zhao Y, Ooi EE, Lescar J, Luo D, Jans DA, Forwood JK, Vasudevan SG. The C-terminal 18 Amino Acid Region of Dengue Virus NS5 Regulates its Subcellular Localization and Contains a Conserved Arginine Residue Essential for Infectious Virus Production. PLoS Pathog 2016; 12:e1005886. [PMID: 27622521 PMCID: PMC5021334 DOI: 10.1371/journal.ppat.1005886] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Accepted: 08/22/2016] [Indexed: 11/24/2022] Open
Abstract
Dengue virus NS5 is the most highly conserved amongst the viral non-structural proteins and is responsible for capping, methylation and replication of the flavivirus RNA genome. Interactions of NS5 with host proteins also modulate host immune responses. Although replication occurs in the cytoplasm, an unusual characteristic of DENV2 NS5 is that it localizes to the nucleus during infection with no clear role in replication or pathogenesis. We examined NS5 of DENV1 and 2, which exhibit the most prominent difference in nuclear localization, employing a combination of functional and structural analyses. Extensive gene swapping between DENV1 and 2 NS5 identified that the C-terminal 18 residues (Cter18) alone was sufficient to direct the protein to the cytoplasm or nucleus, respectively. The low micromolar binding affinity between NS5 Cter18 and the nuclear import receptor importin-alpha (Impα), allowed their molecular complex to be purified, crystallised and visualized at 2.2 Å resolution using x-ray crystallography. Structure-guided mutational analysis of this region in GFP-NS5 clones of DENV1 or 2 and in a DENV2 infectious clone reveal residues important for NS5 subcellular localization. Notably, the trans conformation adopted by Pro-884 allows proper presentation for binding Impα and mutating this proline to Thr, as present in DENV1 NS5, results in mislocalizaion of NS5 to the cytoplasm without compromising virus fitness. In contrast, a single mutation to alanine at NS5 position R888, a residue conserved in all flaviviruses, resulted in a completely non-viable virus, and the R888K mutation led to a severely attenuated phentoype, even though NS5 was located in the nucleus. R888 forms a hydrogen bond with Y838 that is also conserved in all flaviviruses. Our data suggests an evolutionarily conserved function for NS5 Cter18, possibly in RNA interactions that are critical for replication, that is independent of its role in subcellular localization. DENV NS5 is critical for virus RNA replication and an important drug target based on its high sequence conservation across serotypes, and the successful development of potent drugs that target the homologous NS5B of hepatitis C virus. NS5 also mediates other functions that are important for innate and adaptive immune responses by the infected host. Extensive gene swapping and functional analyses between NS5 of DENV serotypes 1 and 2, that are the two most disparate in terms of nuclear vs cytoplasmic localization of NS5 identified the last 18 amino acid residues of the ~900 amino-acid residues long protein to be responsible for subcellular localization. Because this region is very flexible and not easily seen in crystal structures of DENV NS5, co-crystals of the newly discovered peptide region with importin α were obtained. Structure-based mutations introduced into a DENV2 infectious clone showed that the proline to threonine at position 884 resulted in NS5 being mostly cytoplasmic without affecting virus replication. However mutation of arginine 888, which is conserved in all flaviviruses, to alanine resulted in a completely non-viable virus, suggesting that the C-terminal region is essential for NS5 function irrespective of its role in subcellular location.
Collapse
Affiliation(s)
- Moon Y. F. Tay
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore
| | - Kate Smith
- School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, New South Wales, Australia
| | - Ivan H. W. Ng
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore
| | - Kitti W. K. Chan
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Yongqian Zhao
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore
| | - Eng Eong Ooi
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Julien Lescar
- School of Biological Sciences, Nanyang Technological University, Singapore
- UPMC UMRS CR7—CNRS ERL 8255-INSERM U1135 Centre d’Immunologie et des Maladies Infectieuses. Centre Hospitalier Universitaire Pitié-Salpêtrière, Faculté de Médecine Pierre et Marie Curie, Paris, France
| | - Dahai Luo
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
| | - David A. Jans
- Nuclear Signalling Laboratory, Department of Biochemistry and Molecular Biology, Monash University, Melbourne, Victoria, Australia
| | - Jade K. Forwood
- School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, New South Wales, Australia
| | - Subhash G. Vasudevan
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- * E-mail:
| |
Collapse
|
50
|
Coloma J, Jain R, Rajashankar KR, García-Sastre A, Aggarwal AK. Structures of NS5 Methyltransferase from Zika Virus. Cell Rep 2016; 16:3097-3102. [PMID: 27633330 PMCID: PMC5074680 DOI: 10.1016/j.celrep.2016.08.091] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 08/27/2016] [Accepted: 08/30/2016] [Indexed: 12/11/2022] Open
Abstract
The Zika virus (ZIKV) poses a major public health emergency. To aid in the development of antivirals, we present two high-resolution crystal structures of the ZIKV NS5 methyltransferase: one bound to S-adenosylmethionine (SAM) and the other bound to SAM and 7-methyl guanosine diphosphate (7-MeGpp). We identify features of ZIKV NS5 methyltransferase that lend to structure-based antiviral drug discovery. Specifically, SAM analogs with functionalities on the Cβ atom of the methionine portion of the molecules that occupy the RNA binding tunnel may provide better specificity relative to human RNA methyltransferases.
Collapse
Affiliation(s)
- Javier Coloma
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Rinku Jain
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Kanagalaghatta R Rajashankar
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA; NE-CAT, Advanced Photon Source, Argonne, IL 60439, USA
| | - Adolfo García-Sastre
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Department of Medicine, Division of Infectious Diseases, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Aneel K Aggarwal
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
| |
Collapse
|