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Sarratea MB, Alberti AS, Redolfi DM, Truant SN, Iannantuono Lopez LV, Bivona AE, Mariuzza RA, Fernández MM, Malchiodi EL. Zika virus NS4B protein targets TANK-binding kinase 1 and inhibits type I interferon production. Biochim Biophys Acta Gen Subj 2023; 1867:130483. [PMID: 37802371 DOI: 10.1016/j.bbagen.2023.130483] [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: 04/23/2023] [Revised: 09/26/2023] [Accepted: 10/02/2023] [Indexed: 10/10/2023]
Abstract
BACKGROUND During viral infections, nucleic acid sensing by intracellular receptors can trigger type I interferon (IFN-I) production, key mediators in antiviral innate immunity. However, many flaviviruses use non-structural proteins to evade immune sensing favoring their survival. These mechanisms remain poorly characterized. Here, we studied the role of Zika virus (ZIKV) NS4B protein in the inhibition of IFN-I induction pathway and its biophysical interaction with host proteins. METHODS Using different cell-based assays, we studied the effect of ZIKV NS4B in the activation of interferon regulatory factors (IRFs), NF-κB, cytokines secretion and the expression of interferon-stimulating genes (ISG). We also analyzed the in vitro interaction between recombinant ZIKV NS4B and TANK-binding kinase 1 (TBK1) using surface plasmon resonance (SPR). RESULTS Transfection assays showed that ZIKV NS4B inhibits IRFs activation involved in different nucleic acid sensing cascades. Cells expressing NS4B secreted lower levels of IFN-β and IL-6. Furthermore, early induction of ISGs was also restricted by ZIKV NS4B. For the first time, we demonstrate by SPR assays that TBK1, a critical component in IFN-I production pathway, binds directly to ZIKV NS4B (KD of 3.7 × 10-6 M). In addition, we show that the N-terminal region of NS4B is directly involved in this interaction. CONCLUSIONS Altogether, our results strongly support that ZIKV NS4B affects nucleic acid sensing cascades and disrupts the TBK1/IRF3 axis, leading to an impairment of IFN-β production. SIGNIFICANCE This study provides the first biophysical data of the interaction between ZIKV NS4B and TBK1, and highlights the role of ZIKV NS4B in evading the early innate immune response.
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Affiliation(s)
- Maria B Sarratea
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología-IDEHU (UBA-CONICET), Junín 956, C1113AAD Buenos Aires, Argentina; W.M. Keck Laboratory for Structural Biology, University of Maryland Institute for Bioscience and Biotechnology Research, Rockville, MD 20850, USA
| | - Andrés Sánchez Alberti
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología-IDEHU (UBA-CONICET), Junín 956, C1113AAD Buenos Aires, Argentina; Universidad de Buenos Aires, Facultad de Medicina, Departamento de Microbiología, Parasitología e Inmunología-IMPAM (UBA-CONICET), Paraguay 2155, C1121ABG Buenos Aires, Argentina
| | - Daniela M Redolfi
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología-IDEHU (UBA-CONICET), Junín 956, C1113AAD Buenos Aires, Argentina
| | - Sofía Noli Truant
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología-IDEHU (UBA-CONICET), Junín 956, C1113AAD Buenos Aires, Argentina
| | - Laura V Iannantuono Lopez
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología-IDEHU (UBA-CONICET), Junín 956, C1113AAD Buenos Aires, Argentina
| | - Augusto E Bivona
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología-IDEHU (UBA-CONICET), Junín 956, C1113AAD Buenos Aires, Argentina; Universidad de Buenos Aires, Facultad de Medicina, Departamento de Microbiología, Parasitología e Inmunología-IMPAM (UBA-CONICET), Paraguay 2155, C1121ABG Buenos Aires, Argentina
| | - Roy A Mariuzza
- W.M. Keck Laboratory for Structural Biology, University of Maryland Institute for Bioscience and Biotechnology Research, Rockville, MD 20850, USA; Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA
| | - Marisa M Fernández
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología-IDEHU (UBA-CONICET), Junín 956, C1113AAD Buenos Aires, Argentina.
| | - Emilio L Malchiodi
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología-IDEHU (UBA-CONICET), Junín 956, C1113AAD Buenos Aires, Argentina; Universidad de Buenos Aires, Facultad de Medicina, Departamento de Microbiología, Parasitología e Inmunología-IMPAM (UBA-CONICET), Paraguay 2155, C1121ABG Buenos Aires, Argentina.
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2
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Huang Q, Ng HQ, Loh YY, Ke Z, Lim WH, Kang C. Backbone 1H, 15N and 13C resonance assignments for an E2 ubiquitin conjugating enzyme-UBE2T. BIOMOLECULAR NMR ASSIGNMENTS 2023; 17:269-274. [PMID: 37773242 DOI: 10.1007/s12104-023-10154-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Accepted: 09/20/2023] [Indexed: 10/01/2023]
Abstract
Ubiquitin-conjugating enzyme E2 T (UBE2T) plays important roles in ubiquitination of proteins through participation in transferring ubiquitin to its substrate. Due to its importance in protein modifications, UBE2T associates with diverse diseases and serves as an important target for drug discovery and development. The crystal structure of UBE2T has been determined and the structure reveals the lack of a druggable pocket for binding to small molecules for clinical applications. Despite the challenge, effort has been made to develop UBE2T inhibitors. We obtained UBE2T constructs with and without the C-terminal region which is flexible in solution. Herein, we report the backbone resonance assignments for human UBE2T without the C-terminal region. The backbone dynamics of UBE2T was also explored. The available assignments will be helpful for hit identification, determining ligand binding site and understanding the mechanism of action of UBE2T inhibitors.
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Affiliation(s)
- Qiwei Huang
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), 10 Biopolis Road, #05-01, Singapore, 138670, Singapore
| | - Hui Qi Ng
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), 10 Biopolis Road, #05-01, Singapore, 138670, Singapore
| | - Yong Yao Loh
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), 10 Biopolis Road, #05-01, Singapore, 138670, Singapore
| | - Zhiyuan Ke
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), 10 Biopolis Road, #05-01, Singapore, 138670, Singapore
| | - Wan Hsin Lim
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), 10 Biopolis Road, #05-01, Singapore, 138670, Singapore
| | - CongBao Kang
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), 10 Biopolis Road, #05-01, Singapore, 138670, Singapore.
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3
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Plante JA, Plante KS, Popov VL, Shinde DP, Widen SG, Buenemann M, Nogueira ML, Vasilakis N. Morphologic and Genetic Characterization of Ilheus Virus, a Potential Emergent Flavivirus in the Americas. Viruses 2023; 15:195. [PMID: 36680235 PMCID: PMC9866216 DOI: 10.3390/v15010195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 01/06/2023] [Accepted: 01/08/2023] [Indexed: 01/12/2023] Open
Abstract
Ilheus virus (ILHV) is a mosquito-borne flavivirus circulating throughout Central and South America and the Caribbean. It has been detected in several mosquito genera including Aedes and Culex, and birds are thought to be its primary amplifying and reservoir host. Here, we describe the genomic and morphologic characterization of ten ILHV strains. Our analyses revealed a high conservation of both the 5'- and 3'-untranslated regions but considerable divergence within the open reading frame. We also showed that ILHV displays a typical flavivirus structural and genomic organization. Our work lays the foundation for subsequent ILHV studies to better understand its transmission cycles, pathogenicity, and emergence potential.
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Affiliation(s)
- Jessica A. Plante
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555-0609, USA
- World Reference Center for Emerging Viruses and Arboviruses, University of Texas Medical Branch, Galveston, TX 77555-0609, USA
- Institute for Human Infection and Immunity, University of Texas Medical Branch, Galveston, TX 77555-0610, USA
| | - Kenneth S. Plante
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555-0609, USA
- World Reference Center for Emerging Viruses and Arboviruses, University of Texas Medical Branch, Galveston, TX 77555-0609, USA
- Institute for Human Infection and Immunity, University of Texas Medical Branch, Galveston, TX 77555-0610, USA
| | - Vsevolod L. Popov
- World Reference Center for Emerging Viruses and Arboviruses, University of Texas Medical Branch, Galveston, TX 77555-0609, USA
- Institute for Human Infection and Immunity, University of Texas Medical Branch, Galveston, TX 77555-0610, USA
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555-0609, USA
| | - Divya P. Shinde
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555-0609, USA
- World Reference Center for Emerging Viruses and Arboviruses, University of Texas Medical Branch, Galveston, TX 77555-0609, USA
- Institute for Human Infection and Immunity, University of Texas Medical Branch, Galveston, TX 77555-0610, USA
| | - Steven G. Widen
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555-0679, USA
| | - Michaela Buenemann
- Department of Geography and Environmental Studies, New Mexico State University, Las Cruces, NM 88003-8801, USA
| | - Mauricio L. Nogueira
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555-0609, USA
- Center for Vector-Borne and Zoonotic Diseases, University of Texas Medical Branch, Galveston, TX 77555-0609, USA
- Department of Dermatological, Infectious and Parasitic Diseases, Faculdade de Medicina de São José do Rio Preto 15090-000, SP, Brazil
| | - Nikos Vasilakis
- World Reference Center for Emerging Viruses and Arboviruses, University of Texas Medical Branch, Galveston, TX 77555-0609, USA
- Institute for Human Infection and Immunity, University of Texas Medical Branch, Galveston, TX 77555-0610, USA
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555-0609, USA
- Center for Vector-Borne and Zoonotic Diseases, University of Texas Medical Branch, Galveston, TX 77555-0609, USA
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Bhardwaj T, Kumar P, Giri R. Investigating the conformational dynamics of Zika virus NS4B protein. Virology 2022; 575:20-35. [PMID: 36037701 DOI: 10.1016/j.virol.2022.08.005] [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: 12/15/2021] [Revised: 08/14/2022] [Accepted: 08/16/2022] [Indexed: 11/27/2022]
Abstract
Zika virus (ZIKV) NS4B protein is a membranotropic multifunctional protein. Despite its versatile functioning, its topology and dynamics are not entirely understood. There is no X-ray or cryo-EM structure available for any flaviviral NS4B full-length protein. In this study, we have investigated the structural dynamics of full-length ZIKV NS4B protein through 3D structure models using molecular dynamics simulations and experimental techniques. Also, we employed a reductionist approach to understand the dynamics of NS4B protein where we studied its N-terminal (residues 1-38), C-terminal (residues 194-251), and cytosolic (residues 131-169) regions in isolation in addition to the full-length protein. Further, using a series of circular dichroism spectroscopic experiments, we validate the cytosolic region as an intrinsically disordered protein region. The microsecond-long all atoms molecular dynamics and replica-exchange simulations complement the experimental observations. Furthermore, we have also studied the NS4B proteins C-terminal regions of four other flaviviruses viz. DENV2, JEV, WNV, and YFV through microsecond simulations to characterize their behaviour in presence and absence of lipid membranes. There are significant differences observed in the conformations of other flavivirus NS4B C-terminal regions in comparison to ZIKV NS4B. Lastly, we have proposed a ZIKV NS4B protein model illustrating its putative topology consisting of various membrane-spanning and non-membranous regions.
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Affiliation(s)
- Taniya Bhardwaj
- School of Biosciences and Bioengineering, Indian Institute of Technology Mandi, VPO Kamand, Himachal Pradesh, 175005, India
| | - Prateek Kumar
- School of Biosciences and Bioengineering, Indian Institute of Technology Mandi, VPO Kamand, Himachal Pradesh, 175005, India
| | - Rajanish Giri
- School of Biosciences and Bioengineering, Indian Institute of Technology Mandi, VPO Kamand, Himachal Pradesh, 175005, India.
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5
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Li Q, Kang C. Dengue virus NS4B protein as a target for developing antivirals. Front Cell Infect Microbiol 2022; 12:959727. [PMID: 36017362 PMCID: PMC9398000 DOI: 10.3389/fcimb.2022.959727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 07/21/2022] [Indexed: 12/04/2022] Open
Abstract
Dengue virus is an important pathogen affecting global population while no specific treatment is available against this virus. Effort has been made to develop inhibitors through targeting viral nonstructural proteins such as NS3 and NS5 with enzymatic activities. No potent inhibitors entering clinical studies have been developed so far due to many challenges. The genome of dengue virus encodes four membrane-bound nonstructural proteins which do not possess any enzymatic activities. Studies have shown that the membrane protein-NS4B is a validated target for drug discovery and several NS4B inhibitors exhibited antiviral activities in various assays and entered preclinical studies.. Here, we summarize the recent studies on dengue NS4B protein. The structure and membrane topology of dengue NS4B derived from biochemical and biophysical studies are described. Function of NS4B through protein-protein interactions and some available NS4B inhibitors are summarized. Accumulated studies demonstrated that cell-based assays play important roles in developing NS4B inhibitors. Although the atomic structure of NS4B is not obtained, target-based drug discovery approach become feasible to develop NS4B inhibitors as recombinant NS4B protein is available.
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Affiliation(s)
- Qingxin Li
- Guangdong Provincial Engineering Laboratory of Biomass High Value Utilization, Institute of Biological and Medical Engineering, Guangdong Academy of Sciences, Guangzhou, China
- *Correspondence: Qingxin Li, ; Congbao Kang,
| | - Congbao Kang
- Experimental Drug Development Centre, Agency for Science, Technology and Research, Singapore, Singapore
- *Correspondence: Qingxin Li, ; Congbao Kang,
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6
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Fishburn AT, Pham OH, Kenaston MW, Beesabathuni NS, Shah PS. Let's Get Physical: Flavivirus-Host Protein-Protein Interactions in Replication and Pathogenesis. Front Microbiol 2022; 13:847588. [PMID: 35308381 PMCID: PMC8928165 DOI: 10.3389/fmicb.2022.847588] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 01/31/2022] [Indexed: 12/23/2022] Open
Abstract
Flaviviruses comprise a genus of viruses that pose a significant burden on human health worldwide. Transmission by both mosquito and tick vectors, and broad host tropism contribute to the presence of flaviviruses globally. Like all viruses, they require utilization of host molecular machinery to facilitate their replication through physical interactions. Their RNA genomes are translated using host ribosomes, synthesizing viral proteins that cooperate with each other and host proteins to reshape the host cell into a factory for virus replication. Thus, dissecting the physical interactions between viral proteins and their host protein targets is essential in our comprehension of how flaviviruses replicate and how they alter host cell behavior. Beyond replication, even single interactions can contribute to immune evasion and pathogenesis, providing potential avenues for therapeutic intervention. Here, we review protein interactions between flavivirus and host proteins that contribute to virus replication, immune evasion, and disease.
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Affiliation(s)
- Adam T Fishburn
- Department of Microbiology and Molecular Genetics, University of California, Davis, Davis, CA, United States
| | - Oanh H Pham
- Department of Microbiology and Molecular Genetics, University of California, Davis, Davis, CA, United States
| | - Matthew W Kenaston
- Department of Microbiology and Molecular Genetics, University of California, Davis, Davis, CA, United States
| | - Nitin S Beesabathuni
- Department of Microbiology and Molecular Genetics, University of California, Davis, Davis, CA, United States.,Department of Chemical Engineering, University of California, Davis, Davis, CA, United States
| | - Priya S Shah
- Department of Microbiology and Molecular Genetics, University of California, Davis, Davis, CA, United States.,Department of Chemical Engineering, University of California, Davis, Davis, CA, United States
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7
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Li Q, Kang C. Structures and Dynamics of Dengue Virus Nonstructural Membrane Proteins. MEMBRANES 2022; 12:membranes12020231. [PMID: 35207152 PMCID: PMC8880049 DOI: 10.3390/membranes12020231] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 02/11/2022] [Accepted: 02/15/2022] [Indexed: 02/01/2023]
Abstract
Dengue virus is an important human pathogen threating people, especially in tropical and sub-tropical regions. The viral genome has one open reading frame and encodes one polyprotein which can be processed into structural and nonstructural (NS) proteins. Four of the seven nonstructural proteins, NS2A, NS2B, NS4A and NS4B, are membrane proteins. Unlike NS3 or NS5, these proteins do not harbor any enzymatic activities, but they play important roles in viral replication through interactions with viral or host proteins to regulate important pathways and enzymatic activities. The location of these proteins on the cell membrane and the functional roles in viral replication make them important targets for antiviral development. Indeed, NS4B inhibitors exhibit antiviral activities in different assays. Structural studies of these proteins are hindered due to challenges in crystallization and the dynamic nature of these proteins. In this review, the function and membrane topologies of dengue nonstructural membrane proteins are presented. The roles of solution NMR spectroscopy in elucidating the structure and dynamics of these proteins are introduced. The success in the development of NS4B inhibitors proves that this class of proteins is an attractive target for antiviral development.
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Affiliation(s)
- Qingxin Li
- Guangdong Provincial Engineering Laboratory of Biomass High Value Utilization, Institute of Biological and Medical Engineering, Guangdong Academy of Sciences, Guangzhou 510316, China
- Correspondence: (Q.L.); (C.K.)
| | - Congbao Kang
- Experimental Drug Development Centre, Agency for Science, Technology and Research, 10 Biopolis Road, #5-01, Singapore 138670, Singapore
- Correspondence: (Q.L.); (C.K.)
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8
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Li Q, Huang Q, Kang C. Secondary Structures of the Transmembrane Domain of SARS-CoV-2 Spike Protein in Detergent Micelles. Int J Mol Sci 2022; 23:ijms23031040. [PMID: 35162961 PMCID: PMC8834715 DOI: 10.3390/ijms23031040] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 01/08/2022] [Accepted: 01/14/2022] [Indexed: 01/11/2023] Open
Abstract
Spike protein of SARS-CoV-2 contains a single-span transmembrane (TM) domain and plays roles in receptor binding, viral attachment and viral entry to the host cells. The TM domain of spike protein is critical for viral infectivity. Herein, the TM domain of spike protein of SARS-CoV-2 was reconstituted in detergent micelles and subjected to structural analysis using solution NMR spectroscopy. The results demonstrate that the TM domain of the protein forms a helical structure in detergent micelles. An unstructured linker is identified between the TM helix and heptapeptide repeat 2 region. The linker is due to the proline residue at position 1213. Side chains of the three tryptophan residues preceding to and within the TM helix important for the function of S-protein might adopt multiple conformations which may be critical for their function. The side chain of W1212 was shown to be exposed to solvent and the side chains of residues W1214 and W1217 are buried in micelles. Relaxation study shows that the TM helix is rigid in solution while several residues have exchanges. The secondary structure and dynamics of the TM domain in this study provide insights into the function of the TM domain of spike protein.
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Affiliation(s)
- Qingxin Li
- Guangdong Provincial Engineering Laboratory of Biomass High Value Utilization, Institute of Biological and Medical Engineering, Guangdong Academy of Sciences, Guangzhou 510316, China;
| | - Qiwei Huang
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), Singapore 138670, Singapore;
| | - Congbao Kang
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), Singapore 138670, Singapore;
- Correspondence:
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In Silico Analysis of Dengue Virus Serotype 2 Mutations Detected at the Intrahost Level in Patients with Different Clinical Outcomes. Microbiol Spectr 2021; 9:e0025621. [PMID: 34468189 PMCID: PMC8557815 DOI: 10.1128/spectrum.00256-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Intrahost genetic diversity is thought to facilitate arbovirus adaptation to changing environments and hosts, and it may also be linked to viral pathogenesis. Intending to shed light on the viral determinants for severe dengue pathogenesis, we previously analyzed the DENV-2 intrahost genetic diversity in 68 patients clinically classified as dengue fever (n = 31), dengue with warning signs (n = 19), and severe dengue (n = 18), performing viral whole-genome deep sequencing from clinical samples with an amplicon-free approach. From it, we identified a set of 141 relevant mutations distributed throughout the viral genome that deserved further attention. Therefore, we employed molecular modeling to recreate three-dimensional models of the viral proteins and secondary RNA structures to map the mutations and assess their potential effects. Results showed that, in general lines, disruptive variants were identified primarily among dengue fever cases. In contrast, potential immune-escape variants were associated mainly with warning signs and severe cases, in line with the latter's longer intrahost evolution times. Furthermore, several mutations were located on protein-surface regions, with no associated function. They could represent sites of further investigation, as the interaction of viral and host proteins is critical for both host immunomodulation and virus hijacking of the cellular machinery. The present analysis provides new information about the implications of the intrahost genetic diversity of DENV-2, contributing to the knowledge about the viral factors possibly involved in its pathogenesis within the human host. Strengthening our results with functional studies could allow many of these variants to be considered in the design of therapeutic or prophylactic compounds and the improvement of diagnostic assays. IMPORTANCE Previous evidence showed that intrahost genetic diversity in arboviruses may be linked to viral pathogenesis and that one or a few amino acid replacements within a single protein are enough to modify a biological feature of an RNA virus. To assess dengue virus serotype 2 determinants potentially involved in pathogenesis, we previously analyzed the intrahost genetic diversity of the virus in patients with different clinical outcomes and identified a set of 141 mutations that deserved further study. Thus, through a molecular modeling approach, we showed that disruptive variants were identified primarily among cases with mild dengue fever, while potential immune-escape variants were mainly associated with cases of greater severity. We believe that some of the variants pointed out in this study were attractive enough to be potentially considered in future intelligent designs of therapeutic or prophylactic compounds or the improvement of diagnostic tools. The present analysis provides new information about DENV-2 viral factors possibly involved in its pathogenesis within the human host.
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10
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Structure and Dynamics of Zika Virus Protease and Its Insights into Inhibitor Design. Biomedicines 2021; 9:biomedicines9081044. [PMID: 34440248 PMCID: PMC8394600 DOI: 10.3390/biomedicines9081044] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 08/04/2021] [Accepted: 08/16/2021] [Indexed: 12/16/2022] Open
Abstract
Zika virus (ZIKV)—a member of the Flaviviridae family—is an important human pathogen. Its genome encodes a polyprotein that can be further processed into structural and non-structural proteins. ZIKV protease is an important target for antiviral development due to its role in cleaving the polyprotein to release functional viral proteins. The viral protease is a two-component protein complex formed by NS2B and NS3. Structural studies using different approaches demonstrate that conformational changes exist in the protease. The structures and dynamics of this protease in the absence and presence of inhibitors were explored to provide insights into the inhibitor design. The dynamic nature of residues binding to the enzyme cleavage site might be important for the function of the protease. Due to the charges at the protease cleavage site, it is challenging to develop small-molecule compounds acting as substrate competitors. Developing small-molecule compounds to inhibit protease activity through an allosteric mechanism is a feasible strategy because conformational changes are observed in the protease. Herein, structures and dynamics of ZIKV protease are summarized. The conformational changes of ZIKV protease and other proteases in the same family are discussed. The progress in developing allosteric inhibitors is also described. Understanding the structures and dynamics of the proteases are important for designing potent inhibitors.
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11
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Moquin SA, Simon O, Karuna R, Lakshminarayana SB, Yokokawa F, Wang F, Saravanan C, Zhang J, Day CW, Chan K, Wang QY, Lu S, Dong H, Wan KF, Lim SP, Liu W, Seh CC, Chen YL, Xu H, Barkan DT, Kounde CS, Sim WLS, Wang G, Yeo HQ, Zou B, Chan WL, Ding M, Song JG, Li M, Osborne C, Blasco F, Sarko C, Beer D, Bonamy GMC, Sasseville VG, Shi PY, Diagana TT, Yeung BKS, Gu F. NITD-688, a pan-serotype inhibitor of the dengue virus NS4B protein, shows favorable pharmacokinetics and efficacy in preclinical animal models. Sci Transl Med 2021; 13:13/579/eabb2181. [PMID: 33536278 DOI: 10.1126/scitranslmed.abb2181] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 01/13/2021] [Indexed: 12/12/2022]
Abstract
Dengue virus (DENV) is a mosquito-borne flavivirus that poses a threat to public health, yet no antiviral drug is available. We performed a high-throughput phenotypic screen using the Novartis compound library and identified candidate chemical inhibitors of DENV. This chemical series was optimized to improve properties such as anti-DENV potency and solubility. The lead compound, NITD-688, showed strong potency against all four serotypes of DENV and demonstrated excellent oral efficacy in infected AG129 mice. There was a 1.44-log reduction in viremia when mice were treated orally at 30 milligrams per kilogram twice daily for 3 days starting at the time of infection. NITD-688 treatment also resulted in a 1.16-log reduction in viremia when mice were treated 48 hours after infection. Selection of resistance mutations and binding studies with recombinant proteins indicated that the nonstructural protein 4B is the target of NITD-688. Pharmacokinetic studies in rats and dogs showed a long elimination half-life and good oral bioavailability. Extensive in vitro safety profiling along with exploratory rat and dog toxicology studies showed that NITD-688 was well tolerated after 7-day repeat dosing, demonstrating that NITD-688 may be a promising preclinical candidate for the treatment of dengue.
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Affiliation(s)
- Stephanie A Moquin
- Novartis Institutes for Biomedical Research, Emeryville, CA 94608, USA.,Novartis Institute for Tropical Diseases, Emeryville, CA 94608, USA
| | - Oliver Simon
- Novartis (Singapore) Pte Ltd, Singapore 117432, Singapore
| | - Ratna Karuna
- Novartis Institute for Tropical Diseases, Singapore 138670, Singapore
| | | | - Fumiaki Yokokawa
- Novartis Institute for Tropical Diseases, Emeryville, CA 94608, USA
| | - Feng Wang
- Novartis Institutes for Biomedical Research, Emeryville, CA 94608, USA
| | - Chandra Saravanan
- Novartis Institutes for Biomedical Research, Translational Medicine: Preclinical Safety, Cambridge, MA 02139, USA
| | - Jin Zhang
- Novartis Institutes for Biomedical Research, Translational Medicine: Pharmacokinetics, East Hanover, NJ 07936, USA
| | - Craig W Day
- Institute for Antiviral Research, Utah State University, Logan, UT 84322, USA
| | - Katherine Chan
- Novartis Institute for Tropical Diseases, Emeryville, CA 94608, USA
| | - Qing-Yin Wang
- Novartis Institute for Tropical Diseases, Singapore 138670, Singapore
| | - Siyan Lu
- Novartis Institute for Tropical Diseases, Singapore 138670, Singapore
| | - Hongping Dong
- Novartis Institute for Tropical Diseases, Singapore 138670, Singapore
| | - Kah Fei Wan
- Novartis Institute for Tropical Diseases, Singapore 138670, Singapore
| | - Siew Pheng Lim
- Novartis Institute for Tropical Diseases, Singapore 138670, Singapore
| | - Wei Liu
- Novartis Institute for Tropical Diseases, Singapore 138670, Singapore
| | - Cheah Chen Seh
- Novartis Institute for Tropical Diseases, Singapore 138670, Singapore
| | - Yen-Liang Chen
- Novartis Institute for Tropical Diseases, Emeryville, CA 94608, USA
| | - Haoying Xu
- Novartis Institute for Tropical Diseases, Singapore 138670, Singapore
| | - David T Barkan
- Novartis Institutes for Biomedical Research, Emeryville, CA 94608, USA
| | - Cyrille S Kounde
- Novartis Institute for Tropical Diseases, Singapore 138670, Singapore
| | | | - Gang Wang
- Novartis Institute for Tropical Diseases, Singapore 138670, Singapore
| | - Hui-Quan Yeo
- Novartis Institute for Tropical Diseases, Singapore 138670, Singapore
| | - Bin Zou
- Novartis Institute for Tropical Diseases, Singapore 138670, Singapore
| | - Wai Ling Chan
- Novartis Institute for Tropical Diseases, Singapore 138670, Singapore
| | - Mei Ding
- Novartis Institute for Tropical Diseases, Singapore 138670, Singapore
| | - Jae-Geun Song
- Novartis Institutes for Biomedical Research, Emeryville, CA 94608, USA
| | - Min Li
- Novartis Institutes for Biomedical Research, Emeryville, CA 94608, USA
| | - Colin Osborne
- Novartis Institute for Tropical Diseases, Emeryville, CA 94608, USA
| | - Francesca Blasco
- Novartis Institute for Tropical Diseases, Singapore 138670, Singapore
| | | | - David Beer
- Novartis Institute for Tropical Diseases, Singapore 138670, Singapore
| | | | - Vito G Sasseville
- Novartis Institutes for Biomedical Research, Translational Medicine: Preclinical Safety, Cambridge, MA 02139, USA
| | - Pei-Yong Shi
- Novartis Institute for Tropical Diseases, Singapore 138670, Singapore
| | | | - Bryan K S Yeung
- Novartis Institute for Tropical Diseases, Singapore 138670, Singapore.
| | - Feng Gu
- Novartis Institute for Tropical Diseases, Emeryville, CA 94608, USA.
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12
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Molecular Insights into the Flavivirus Replication Complex. Viruses 2021; 13:v13060956. [PMID: 34064113 PMCID: PMC8224304 DOI: 10.3390/v13060956] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Revised: 05/17/2021] [Accepted: 05/17/2021] [Indexed: 12/11/2022] Open
Abstract
Flaviviruses are vector-borne RNA viruses, many of which are clinically relevant human viral pathogens, such as dengue, Zika, Japanese encephalitis, West Nile and yellow fever viruses. Millions of people are infected with these viruses around the world each year. Vaccines are only available for some members of this large virus family, and there are no effective antiviral drugs to treat flavivirus infections. The unmet need for vaccines and therapies against these flaviviral infections drives research towards a better understanding of the epidemiology, biology and immunology of flaviviruses. In this review, we discuss the basic biology of the flavivirus replication process and focus on the molecular aspects of viral genome replication. Within the virus-induced intracellular membranous compartments, flaviviral RNA genome replication takes place, starting from viral poly protein expression and processing to the assembly of the virus RNA replication complex, followed by the delivery of the progeny viral RNA to the viral particle assembly sites. We attempt to update the latest understanding of the key molecular events during this process and highlight knowledge gaps for future studies.
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13
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Ci Y, Shi L. Compartmentalized replication organelle of flavivirus at the ER and the factors involved. Cell Mol Life Sci 2021; 78:4939-4954. [PMID: 33846827 PMCID: PMC8041242 DOI: 10.1007/s00018-021-03834-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 03/16/2021] [Accepted: 04/01/2021] [Indexed: 12/14/2022]
Abstract
Flaviviruses are positive-sense single-stranded RNA viruses that pose a considerable threat to human health. Flaviviruses replicate in compartmentalized replication organelles derived from the host endoplasmic reticulum (ER). The characteristic architecture of flavivirus replication organelles includes invaginated vesicle packets and convoluted membrane structures. Multiple factors, including both viral proteins and host factors, contribute to the biogenesis of the flavivirus replication organelle. Several viral nonstructural (NS) proteins with membrane activity induce ER rearrangement to build replication compartments, and other NS proteins constitute the replication complexes (RC) in the compartments. Host protein and lipid factors facilitate the formation of replication organelles. The lipid membrane, proteins and viral RNA together form the functional compartmentalized replication organelle, in which the flaviviruses efficiently synthesize viral RNA. Here, we reviewed recent advances in understanding the structure and biogenesis of flavivirus replication organelles, and we further discuss the function of virus NS proteins and related host factors as well as their roles in building the replication organelle.
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Affiliation(s)
- Yali Ci
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China. .,Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China.
| | - Lei Shi
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China. .,Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China.
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14
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Christy MP, Uekusa Y, Gerwick L, Gerwick WH. Natural Products with Potential to Treat RNA Virus Pathogens Including SARS-CoV-2. JOURNAL OF NATURAL PRODUCTS 2021; 84:161-182. [PMID: 33352046 PMCID: PMC7771248 DOI: 10.1021/acs.jnatprod.0c00968] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Indexed: 05/03/2023]
Abstract
Three families of RNA viruses, the Coronaviridae, Flaviviridae, and Filoviridae, collectively have great potential to cause epidemic disease in human populations. The current SARS-CoV-2 (Coronaviridae) responsible for the COVID-19 pandemic underscores the lack of effective medications currently available to treat these classes of viral pathogens. Similarly, the Flaviviridae, which includes such viruses as Dengue, West Nile, and Zika, and the Filoviridae, with the Ebola-type viruses, as examples, all lack effective therapeutics. In this review, we present fundamental information concerning the biology of these three virus families, including their genomic makeup, mode of infection of human cells, and key proteins that may offer targeted therapies. Further, we present the natural products and their derivatives that have documented activities to these viral and host proteins, offering hope for future mechanism-based antiviral therapeutics. By arranging these potential protein targets and their natural product inhibitors by target type across these three families of virus, new insights are developed, and crossover treatment strategies are suggested. Hence, natural products, as is the case for other therapeutic areas, continue to be a promising source of structurally diverse new anti-RNA virus therapeutics.
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Affiliation(s)
- Mitchell P. Christy
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093, United States
| | - Yoshinori Uekusa
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093, United States
- Faculty of Pharmacy, Keio University, 1-5-30 Shibakoen, Minato-ku, Tokyo, 105-8512, Japan
| | - Lena Gerwick
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093, United States
| | - William H. Gerwick
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093, United States
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California 92093, United States
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15
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Xing H, Xu S, Jia F, Yang Y, Xu C, Qin C, Shi L. Zika NS2B is a crucial factor recruiting NS3 to the ER and activating its protease activity. Virus Res 2019; 275:197793. [PMID: 31676367 DOI: 10.1016/j.virusres.2019.197793] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 10/18/2019] [Accepted: 10/22/2019] [Indexed: 01/10/2023]
Abstract
Zika virus (ZIKV) is an emergent flavivirus associated with severe neurological disorders. ZIKV NS3 protein is a viral protease that cleaves the ZIKV polyprotein precursor into individual viral proteins. In this study, we found that ZIKV NS3 by itself exhibited mitochondrial localization, which was quite different from its endoplasmic reticulum (ER) localization in ZIKV-infected cells. We screened viral proteins and identified NS2B as the bona fide recruiter of NS3 to the ER. The NS2B C-terminal tail interacted with NS3 protease domain to retain NS3 on the ER. β-Sheet motifs that formed between NS2B and the NS3 protease domain played important roles in their interaction, while mutation in the β-strand of NS2B attenuated NS2B-NS3 interaction and impaired the ability of NS3 protease to cleave the polyprotein precursor into multiple viral proteins. Consequently, NS2B mutations led to severe inhibition of ZIKV replication and production due to insufficient NS3 protease activity. In summary, our study reveals the critical role of NS2B in NS3 recruitment and protease function and provides mechanistic insight into ZIKV replication.
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Affiliation(s)
- Huaipeng Xing
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China; Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China
| | - Shan Xu
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China; Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China
| | - Fangfei Jia
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China; Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China
| | - Yang Yang
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China; Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China
| | - Caimin Xu
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China; Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China
| | - Chengfeng Qin
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100005, China.
| | - Lei Shi
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China; Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China.
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16
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Kang C. 19F-NMR in Target-based Drug Discovery. Curr Med Chem 2019; 26:4964-4983. [PMID: 31187703 DOI: 10.2174/0929867326666190610160534] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2018] [Revised: 08/14/2018] [Accepted: 03/13/2019] [Indexed: 02/06/2023]
Abstract
Solution NMR spectroscopy plays important roles in understanding protein structures, dynamics and protein-protein/ligand interactions. In a target-based drug discovery project, NMR can serve an important function in hit identification and lead optimization. Fluorine is a valuable probe for evaluating protein conformational changes and protein-ligand interactions. Accumulated studies demonstrate that 19F-NMR can play important roles in fragment- based drug discovery (FBDD) and probing protein-ligand interactions. This review summarizes the application of 19F-NMR in understanding protein-ligand interactions and drug discovery. Several examples are included to show the roles of 19F-NMR in confirming identified hits/leads in the drug discovery process. In addition to identifying hits from fluorinecontaining compound libraries, 19F-NMR will play an important role in drug discovery by providing a fast and robust way in novel hit identification. This technique can be used for ranking compounds with different binding affinities and is particularly useful for screening competitive compounds when a reference ligand is available.
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Affiliation(s)
- CongBao Kang
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), 10 Biopolis Road, #05-01, Singapore, 138670, Singapore
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17
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Xu J, Xie X, Ye N, Zou J, Chen H, White MA, Shi PY, Zhou J. Design, Synthesis, and Biological Evaluation of Substituted 4,6-Dihydrospiro[[1,2,3]triazolo[4,5- b]pyridine-7,3'-indoline]-2',5(3 H)-dione Analogues as Potent NS4B Inhibitors for the Treatment of Dengue Virus Infection. J Med Chem 2019; 62:7941-7960. [PMID: 31403780 DOI: 10.1021/acs.jmedchem.9b00698] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A series of substituted 4,6-dihydrospiro[[1,2,3]triazolo[4,5-b]pyridine-7,3'-indoline]-2',5(3H)-dione analogues were synthesized and evaluated as potent dengue virus inhibitors. Throughout a structure-activity relationship exploration on the amide of the indolone moiety, a wide range of substitutions were found to be well tolerated for chemical optimization at this position. Among these compounds, 15 (JMX0254) displayed the most potent and broad inhibitory activities, effective against DENV-1 to -3 with EC50 values of 0.78, 0.16, and 0.035 μM, respectively, while compounds 16, 21, 27-29, 47, and 70 exhibited relatively moderate to high activities with low micromolar to nanomolar potency against all four serotypes. The biotinylated compound 73 enriched NS4B protein from cell lysates in pull-down studies, and the findings together with the mutation investigations further validated dengue NS4B protein as the target of this class of compounds. More importantly, compound 15 exhibited good in vivo pharmacokinetic properties and efficacy in the A129 mouse model, indicating its therapeutic potential against the dengue virus infection as a drug candidate for further preclinical development.
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18
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Reyes-Ruiz JM, Osuna-Ramos JF, Bautista-Carbajal P, Jaworski E, Soto-Acosta R, Cervantes-Salazar M, Angel-Ambrocio AH, Castillo-Munguía JP, Chávez-Munguía B, De Nova-Ocampo M, Routh A, Del Ángel RM, Salas-Benito JS. Mosquito cells persistently infected with dengue virus produce viral particles with host-dependent replication. Virology 2019; 531:1-18. [PMID: 30844508 DOI: 10.1016/j.virol.2019.02.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 02/22/2019] [Accepted: 02/26/2019] [Indexed: 11/26/2022]
Abstract
Dengue viruses (DENV) are important arboviruses that can establish a persistent infection in its mosquito vector Aedes. Mosquitoes have a short lifetime in nature which makes trying to study the processes that take place during persistent viral infections in vivo. Therefore, C6/36 cells have been used to study this type of infection. C6/36 cells persistently infected with DENV 2 produce virions that cannot infect BHK -21 cells. We hypothesized that the following passages in mosquito cells have a deleterious impact on DENV fitness in vertebrate cells. Here, we demonstrated that the viral particles released from persistently infected cells were infectious to mosquito but not to vertebrate cells. This host restriction occurs at the replication level and is associated with several mutations in the DENV genome. In summary, our findings provide new information about viral replication fitness in a host-dependent manner.
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Affiliation(s)
- José Manuel Reyes-Ruiz
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico
| | - Juan Fidel Osuna-Ramos
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico
| | - Patricia Bautista-Carbajal
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico
| | - Elizabeth Jaworski
- Department of Biochemistry and Molecular Biology, The University of Texas, Medical Branch, Galveston, TX 77555, USA
| | - Rubén Soto-Acosta
- Department of Biochemistry and Molecular Biology, The University of Texas, Medical Branch, Galveston, TX 77555, USA
| | - Margot Cervantes-Salazar
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico
| | | | - Juan Pablo Castillo-Munguía
- Maestría en Ciencias en Biomedicina Molecular, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Mexico
| | - Bibiana Chávez-Munguía
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico
| | - Mónica De Nova-Ocampo
- Maestría en Ciencias en Biomedicina Molecular, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Mexico
| | - Andrew Routh
- Department of Biochemistry and Molecular Biology, The University of Texas, Medical Branch, Galveston, TX 77555, USA; Sealy Center for Structural Biology and Molecular Biophysics, The University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Rosa María Del Ángel
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico.
| | - Juan Santiago Salas-Benito
- Maestría en Ciencias en Biomedicina Molecular, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Mexico; Doctorado en Ciencias en Biotecnología, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Mexico.
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19
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Silva EM, Conde JN, Allonso D, Ventura GT, Coelho DR, Carneiro PH, Silva ML, Paes MV, Rabelo K, Weissmuller G, Bisch PM, Mohana-Borges R. Dengue virus nonstructural 3 protein interacts directly with human glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and reduces its glycolytic activity. Sci Rep 2019; 9:2651. [PMID: 30804377 PMCID: PMC6389977 DOI: 10.1038/s41598-019-39157-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 01/16/2019] [Indexed: 12/29/2022] Open
Abstract
Dengue is an important mosquito-borne disease and a global public health problem. The disease is caused by dengue virus (DENV), which is a member of the Flaviviridae family and contains a positive single-stranded RNA genome that encodes a single precursor polyprotein that is further cleaved into structural and non-structural proteins. Among these proteins, the non-structural 3 (NS3) protein is very important because it forms a non-covalent complex with the NS2B cofactor, thereby forming the functional viral protease. NS3 also contains a C-terminal ATPase/helicase domain that is essential for RNA replication. Here, we identified 47 NS3-interacting partners using the yeast two-hybrid system. Among those partners, we highlight several proteins involved in host energy metabolism, such as apolipoprotein H, aldolase B, cytochrome C oxidase and glyceraldehyde-3-phosphate dehydrogenase (GAPDH). GAPDH directly binds full-length NS3 and its isolated helicase and protease domains. Moreover, we observed an intense colocalization between the GAPDH and NS3 proteins in DENV2-infected Huh7.5.1 cells, in NS3-transfected BHK-21 cells and in hepatic tissue from a fatal dengue case. Taken together, these results suggest that the human GAPDH-DENV NS3 interaction is involved in hepatic metabolic alterations, which may contribute to the appearance of steatosis in dengue-infected patients. The interaction between GAPDH and full-length NS3 or its helicase domain in vitro as well as in NS3-transfected cells resulted in decreased GAPDH glycolytic activity. Reduced GAPDH glycolytic activity may lead to the accumulation of metabolic intermediates, shifting metabolism to alternative, non-glycolytic pathways. This report is the first to identify the interaction of the DENV2 NS3 protein with the GAPDH protein and to demonstrate that this interaction may play an important role in the molecular mechanism that triggers hepatic alterations.
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Affiliation(s)
- Emiliana M Silva
- Laboratório de Genômica Estrutural, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590, Brazil
| | - Jonas N Conde
- Laboratório de Genômica Estrutural, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590, Brazil
| | - Diego Allonso
- Departamento de Biotecnologia Farmacêutica, Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Gustavo T Ventura
- Laboratório de Genômica Estrutural, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590, Brazil
| | - Diego R Coelho
- Laboratório de Genômica Estrutural, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590, Brazil
| | - Pedro Henrique Carneiro
- Laboratório de Genômica Estrutural, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590, Brazil
| | - Manuela L Silva
- Instituto de Biodiversidade e Sustentabilidade (NUPEM/UFRJ), Universidade Federal do Rio de Janeiro, Macaé, RJ, Brazil
| | - Marciano V Paes
- Laboratório Interdisciplinar de Pesquisa Médica, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brazil
| | - Kíssila Rabelo
- Laboratório de Ultraestrutura e Biologia Tecidual, Universidade Estadual do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Gilberto Weissmuller
- Laboratório de Física Biológica, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590, Brazil
| | - Paulo Mascarello Bisch
- Laboratório de Física Biológica, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590, Brazil
| | - Ronaldo Mohana-Borges
- Laboratório de Genômica Estrutural, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590, Brazil.
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20
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Li Q, Ng HQ, Kang C. Secondary structure and topology of the transmembrane domain of Syndecan‐2 in detergent micelles. FEBS Lett 2019; 593:554-561. [DOI: 10.1002/1873-3468.13335] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 02/03/2019] [Accepted: 02/07/2019] [Indexed: 01/18/2023]
Affiliation(s)
- Qingxin Li
- Institute of Chemical and Engineering Sciences Agency for Science, Technology and Research (A*STAR) Jurong Island Singapore
| | - Hui Qi Ng
- Experimental Therapeutics Centre Experimental Drug Development Centre (EDDC) Agency for Science, Technology and Research (A*STAR) Singapore Singapore
| | - CongBao Kang
- Experimental Therapeutics Centre Experimental Drug Development Centre (EDDC) Agency for Science, Technology and Research (A*STAR) Singapore Singapore
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21
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Ng EY, Loh YR, Li Y, Li Q, Kang C. Expression, purification of Zika virus membrane protein-NS2B in detergent micelles for NMR studies. Protein Expr Purif 2019; 154:1-6. [DOI: 10.1016/j.pep.2018.09.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Revised: 09/17/2018] [Accepted: 09/20/2018] [Indexed: 12/15/2022]
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22
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Li Y, Loh YR, Hung AW, Kang C. Characterization of molecular interactions between Zika virus protease and peptides derived from the C-terminus of NS2B. Biochem Biophys Res Commun 2018; 503:691-696. [DOI: 10.1016/j.bbrc.2018.06.062] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 06/12/2018] [Indexed: 12/16/2022]
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23
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Bui TT, Moi ML, Nabeshima T, Takemura T, Nguyen TT, Nguyen LN, Pham HTT, Nguyen TTT, Manh DH, Dumre SP, Mizukami S, Hirayama K, Tajima S, Le MTQ, Aoyagi K, Hasebe F, Morita K. A single amino acid substitution in the NS4B protein of Dengue virus confers enhanced virus growth and fitness in human cells in vitro through IFN-dependent host response. J Gen Virol 2018; 99:1044-1057. [PMID: 29916798 DOI: 10.1099/jgv.0.001092] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Dengue virus (DENV) replication between mosquito and human hosts is hypothesized to be associated with viral determinants that interact in a differential manner between hosts. However, the understanding of inter-host viral determinants that drive DENV replication and growth between hosts is limited. Through the use of clinical isolates, we identified an amino acid variation of Ala, Met and Val at position 116 of DENV-1 NS4B. While the proportion of virus with the NS4B-116V variant remained constantly high in serial passages in a mosquito cell line, populations of the NS4B-116M and NS4B-116A variants became dominant after serial passages in mammalian cell lines. Using recombinant DENV-1 viruses, the Val to Ala or Met alteration at position NS4B-116 (rDENV-1-NS4B-116A and rDENV-1-NS4B-116M) resulted in enhanced virus growth in human cells in comparison to the clone with Val at NS4B-116 (rDENV-1-NS4B-116V). However, the reverse phenomenon was observed in a mosquito cell line. Additionally, in a human cell line, differential levels of IFN-α/β and IFN-stimulated gene expressions (IFIT3, IFI44L, OAS1) suggested that the enhanced viral growth was dependent on the ability of the NS4B protein to hamper host IFN response during the early phase of infection. Overall, we identified a novel and critical viral determinant at the pTMD3 of NS4B region that displayed differential effects on DENV replication and fitness in human and mosquito cell lines. Taken together, the results suggest the importance of the NS4B protein in virus replication and adaptation between hosts.
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Affiliation(s)
- Thuy Thu Bui
- 1Department of Virology, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan.,2Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Meng Ling Moi
- 1Department of Virology, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Takeshi Nabeshima
- 1Department of Virology, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Taichiro Takemura
- 3NIHE-Nagasaki Friendship Laboratory, Nagasaki University, Hanoi, Vietnam
| | - Trang Thu Nguyen
- 3NIHE-Nagasaki Friendship Laboratory, Nagasaki University, Hanoi, Vietnam
| | - Linh Ngoc Nguyen
- 4Department of Virology, National Institute of Hygiene and Epidemiology, Hanoi, Vietnam
| | - Hang Thi Thu Pham
- 4Department of Virology, National Institute of Hygiene and Epidemiology, Hanoi, Vietnam
| | - Thi Thu Thuy Nguyen
- 4Department of Virology, National Institute of Hygiene and Epidemiology, Hanoi, Vietnam
| | - Dao Huy Manh
- 2Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.,5Department of Immunogenetics, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Shyam Prakash Dumre
- 5Department of Immunogenetics, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Shusaku Mizukami
- 6Department of Clinical Product Development, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Kenji Hirayama
- 5Department of Immunogenetics, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Shigeru Tajima
- 7Department of Virology 1, National Insitute of Infectious Diseases, Tokyo, Japan
| | - Mai Thi Quynh Le
- 4Department of Virology, National Institute of Hygiene and Epidemiology, Hanoi, Vietnam
| | - Kiyoshi Aoyagi
- 8Department of Public Health, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Futoshi Hasebe
- 9Vietnam Research station, Center for Infectious Disease Research in Asia and Africa, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Kouichi Morita
- 1Department of Virology, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
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24
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Lau QY, Li J, Sani MA, Sinha S, Li Y, Ng FM, Kang C, Bhattacharjya S, Separovic F, Verma C, Chia CSB. Elucidating the bactericidal mechanism of action of the linear antimicrobial tetrapeptide BRBR-NH 2. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:1517-1527. [PMID: 29758185 DOI: 10.1016/j.bbamem.2018.05.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 05/09/2018] [Accepted: 05/09/2018] [Indexed: 12/22/2022]
Abstract
Linear antimicrobial peptides, with their rapid bactericidal mode of action, are well-suited for development as topical antibacterial drugs. We recently designed a synthetic linear 4-residue peptide, BRBR-NH2, with potent bactericidal activity against Staphylococcus aureus (MIC 6.25 μM), the main causative pathogen of human skin infections with an unknown mechanism of action. Herein, we describe a series of experiments conducted to gain further insights into its mechanism of action involving electron microscopy, artificial membrane dye leakage, solution- and solid-state NMR spectroscopy followed by molecular dynamics simulations. Experimental results point towards a SMART (Soft Membranes Adapt and Respond, also Transiently) mechanism of action, suggesting that the peptide can be developed as a topical antibacterial agent for treating drug-resistant Staphylococcus aureus infections.
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Affiliation(s)
- Qiu Ying Lau
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore
| | - Jianguo Li
- Bioinformatics Institute, Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, Matrix #07-01, Singapore 138671, Singapore; Singapore Eye Research Institute, The Academia, 20 College Road, Singapore 168751, Singapore
| | - Marc-Antoine Sani
- School of Chemistry, Bio21 Institute, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Sheetal Sinha
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore; Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore 637141, Singapore; Interdisciplinary Graduate School, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
| | - Yan Li
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore
| | - Fui Mee Ng
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore
| | - CongBao Kang
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore
| | - Surajit Bhattacharjya
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore
| | - Frances Separovic
- School of Chemistry, Bio21 Institute, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Chandra Verma
- Bioinformatics Institute, Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, Matrix #07-01, Singapore 138671, Singapore; School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore; Department of Biological Sciences, National University of Singapore, 16 Science Drive 4, Singapore 117558, Singapore
| | - Cheng San Brian Chia
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore.
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25
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The Dengue Virus Replication Complex: From RNA Replication to Protein-Protein Interactions to Evasion of Innate Immunity. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1062:115-129. [PMID: 29845529 DOI: 10.1007/978-981-10-8727-1_9] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Viruses from the Flavivirus family are the causative agents of dengue fever, Zika, Japanese encephalitis, West Nile encephalitis or Yellow fever and constitute major or emerging public health problems. A better understanding of the flavivirus replication cycle is likely to offer new opportunities for the design of antiviral therapies to treat severe conditions provoked by these viruses, but it should also help reveal fundamental biological mechanisms of the host cell. During virus replication, RNA synthesis is mediated by a dynamic and membrane-bound multi-protein assembly, named the replication complex (RC). The RC is composed of both viral and host-cell proteins that assemble within vesicles composed of the endoplasmic reticulum membrane, near the nucleus. At the heart of the flavivirus RC lies NS4B, a viral integral membrane protein that plays a role in virulence and in down-regulating the innate immune response. NS4B binds to the NS2B-NS3 protease-helicase, which itself interacts with the NS5 methyl-transferase polymerase. We present an overview of recent structural and functional data that augment our understanding of how viral RNA is replicated by dengue virus. We focus on structural data that illuminate the various roles played by proteins NS2B-NS3, NS4B and NS5. By participating in viral RNA cap methylation, the NS5 methyltransferase enables the virus to escape the host cell innate immune response. We present the molecular basis for this activity. We summarize what we know about the network of interactions established by NS2B-NS3, NS4B and NS5 (their "interactome"). This leads to a working model that is captured in the form of a rather naïve "cartoon", which we hope will be refined towards an atomic model in the near future.
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26
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Li Y, Lee MY, Loh YR, Kang C. Secondary structure and membrane topology of dengue virus NS4A protein in micelles. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1860:442-450. [PMID: 29055659 DOI: 10.1016/j.bbamem.2017.10.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 09/28/2017] [Accepted: 10/14/2017] [Indexed: 11/18/2022]
Abstract
Dengue virus (DENV) non-structural (NS) 4A is a membrane protein essential for viral replication. The N-terminal region of NS4A contains several helices interacting with the cell membrane and the C-terminal region consists of three potential transmembrane regions. The secondary structure of the intact NS4A is not known as the previous structural studies were carried out on its fragments. In this study, we purified the full-length NS4A of DENV serotype 4 into dodecylphosphocholine (DPC) micelles. Solution NMR studies reveal that NS4A contains six helices in DPC micelles. The N-terminal three helices are amphipathic and interact with the membrane. The C-terminal three helices are embedded in micelles. Our results suggest that NS4A contains three transmembrane helices. Our studies provide for the first time structural information of the intact NS4A of DENV and will be useful for further understanding its role in viral replication.
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Affiliation(s)
- Yan Li
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos, Singapore 138669, Singapore
| | - Michelle Yueqi Lee
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos, Singapore 138669, Singapore
| | - Ying Ru Loh
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos, Singapore 138669, Singapore
| | - CongBao Kang
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos, Singapore 138669, Singapore.
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27
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Li Y, Kang C. Solution NMR Spectroscopy in Target-Based Drug Discovery. Molecules 2017; 22:E1399. [PMID: 28832542 PMCID: PMC6151424 DOI: 10.3390/molecules22091399] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 08/18/2017] [Accepted: 08/18/2017] [Indexed: 12/14/2022] Open
Abstract
Solution NMR spectroscopy is a powerful tool to study protein structures and dynamics under physiological conditions. This technique is particularly useful in target-based drug discovery projects as it provides protein-ligand binding information in solution. Accumulated studies have shown that NMR will play more and more important roles in multiple steps of the drug discovery process. In a fragment-based drug discovery process, ligand-observed and protein-observed NMR spectroscopy can be applied to screen fragments with low binding affinities. The screened fragments can be further optimized into drug-like molecules. In combination with other biophysical techniques, NMR will guide structure-based drug discovery. In this review, we describe the possible roles of NMR spectroscopy in drug discovery. We also illustrate the challenges encountered in the drug discovery process. We include several examples demonstrating the roles of NMR in target-based drug discoveries such as hit identification, ranking ligand binding affinities, and mapping the ligand binding site. We also speculate the possible roles of NMR in target engagement based on recent processes in in-cell NMR spectroscopy.
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Affiliation(s)
- Yan Li
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos, #03-01, Singapore 138669, Singapore.
| | - Congbao Kang
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos, #03-01, Singapore 138669, Singapore.
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