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Smirnov A, Magri A, Lotz R, Han X, Yin C, Harris M, Osterburg C, Dötsch V, McKeating JA, Lu X. ASPP2 binds to hepatitis C virus NS5A protein via an SH3 domain/PxxP motif-mediated interaction and potentiates infection. J Gen Virol 2023; 104:10.1099/jgv.0.001895. [PMID: 37750869 PMCID: PMC7615710 DOI: 10.1099/jgv.0.001895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/27/2023] Open
Abstract
Hepatitis C virus (HCV) infects millions of people worldwide and is a leading cause of liver disease. Despite recent advances in antiviral therapies, viral resistance can limit drug efficacy and understanding the mechanisms that confer viral escape is important. We employ an unbiased interactome analysis to discover host binding partners of the HCV non-structural protein 5A (NS5A), a key player in viral replication and assembly. We identify ASPP2, apoptosis-stimulating protein of p53, as a new host co-factor that binds NS5A via its SH3 domain. Importantly, silencing ASPP2 reduces viral replication and spread. Our study uncovers a previously unknown role for ASPP2 to potentiate HCV RNA replication.
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Affiliation(s)
- Artem Smirnov
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7DQ, UK
- Department of Experimental Medicine, TOR, University of Rome “Tor Vergata”, Rome 00133, Italy
| | - Andrea Magri
- Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7FZ, UK
| | - Rebecca Lotz
- Institute of Biophysical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University, Frankfurt, Germany
| | - Xiaoyue Han
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7DQ, UK
| | - Chunhong Yin
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, UK
| | - Mark Harris
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, UK
| | - Christian Osterburg
- Institute of Biophysical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University, Frankfurt, Germany
| | - Volker Dötsch
- Institute of Biophysical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University, Frankfurt, Germany
| | - Jane A. McKeating
- Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7FZ, UK
- Chinese Academy of Medical Sciences Oxford Institute, University of Oxford, Oxford, UK
| | - Xin Lu
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7DQ, UK
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2
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Miyamoto D, Takeuchi K, Chihara K, Fujieda S, Sada K. Protein tyrosine kinase Abl promotes hepatitis C virus particle assembly via interaction with viral substrate activator NS5A. J Biol Chem 2022; 298:101804. [PMID: 35257746 PMCID: PMC8980994 DOI: 10.1016/j.jbc.2022.101804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 02/26/2022] [Accepted: 02/28/2022] [Indexed: 11/30/2022] Open
Abstract
Previously, we reported that knockdown of Abl protein tyrosine kinase by shRNA or pharmacological inhibition suppresses particle assembly of J6/JFH1 strain–derived hepatitis C virus (HCV) in Huh-7.5 cells. However, the detailed mechanism by which Abl regulates HCV replication remained unclear. In this study, we established Abl-deficient (Abl−) cells through genome editing and compared HCV production between Abl− cells expressing WT or kinase-dead Abl and parental Huh-7.5 cells. Our findings revealed that Abl expression was not required from the stages of virus attachment and entry to viral gene expression; however, the kinase activity of Abl was necessary for the assembly of HCV particles. Reconstitution experiments using human embryonic kidney 293T cells revealed that phosphorylation of Tyr412 in the activation loop of Abl was enhanced by coexpression with the viral nonstructural protein 5A (NS5A) and was abrogated by the substitution of NS5A Tyr330 with Phe (Y330F), suggesting that NS5A functions as a substrate activator of Abl. Abl–NS5A association was also attenuated by the Y330F mutation of NS5A or the kinase-dead Abl, and Abl Tyr412 phosphorylation was not enhanced by NS5A bearing a mutation disabling homodimerization, although the association of Abl with NS5A was still observed. Taken together, these results demonstrate that Abl forms a phosphorylation-dependent complex with dimeric NS5A necessary for viral particle assembly, but that Abl is capable of complex formation with monomeric NS5A regardless of tyrosine phosphorylation. Our findings provide the foundation of a molecular basis for a new hepatitis C treatment strategy using Abl inhibitors.
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Affiliation(s)
- Daisuke Miyamoto
- Department of Otorhinolaryngology Head & Neck Surgery, Faculty of Medical Sciences, University of Fukui, Fukui, Japan; Department of Genome Science and Microbiology, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | - Kenji Takeuchi
- Department of Genome Science and Microbiology, Faculty of Medical Sciences, University of Fukui, Fukui, Japan; Organization for Life Science Advancement Programs, University of Fukui, Fukui, Japan
| | - Kazuyasu Chihara
- Department of Genome Science and Microbiology, Faculty of Medical Sciences, University of Fukui, Fukui, Japan; Organization for Life Science Advancement Programs, University of Fukui, Fukui, Japan
| | - Shigeharu Fujieda
- Department of Otorhinolaryngology Head & Neck Surgery, Faculty of Medical Sciences, University of Fukui, Fukui, Japan; Organization for Life Science Advancement Programs, University of Fukui, Fukui, Japan
| | - Kiyonao Sada
- Department of Genome Science and Microbiology, Faculty of Medical Sciences, University of Fukui, Fukui, Japan; Organization for Life Science Advancement Programs, University of Fukui, Fukui, Japan.
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3
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Li HC, Yang CH, Lo SY. Cellular factors involved in the hepatitis C virus life cycle. World J Gastroenterol 2021; 27:4555-4581. [PMID: 34366623 PMCID: PMC8326260 DOI: 10.3748/wjg.v27.i28.4555] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 04/04/2021] [Accepted: 07/09/2021] [Indexed: 02/06/2023] Open
Abstract
The hepatitis C virus (HCV), an obligatory intracellular pathogen, highly depends on its host cells to propagate successfully. The HCV life cycle can be simply divided into several stages including viral entry, protein translation, RNA replication, viral assembly and release. Hundreds of cellular factors involved in the HCV life cycle have been identified over more than thirty years of research. Characterization of these cellular factors has provided extensive insight into HCV replication strategies. Some of these cellular factors are targets for anti-HCV therapies. In this review, we summarize the well-characterized and recently identified cellular factors functioning at each stage of the HCV life cycle.
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Affiliation(s)
- Hui-Chun Li
- Department of Biochemistry, Tzu Chi University, Hualien 970, Taiwan
| | - Chee-Hing Yang
- Department of Laboratory Medicine and Biotechnology, Tzu Chi University, Hualien 970, Taiwan
| | - Shih-Yen Lo
- Department of Laboratory Medicine and Biotechnology, Tzu Chi University, Hualien 970, Taiwan
- Department of Laboratory Medicine, Buddhist Tzu Chi General Hospital, Hualien 970, Taiwan
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4
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Yurtsever D, Lorent JH. Structural Modifications Controlling Membrane Raft Partitioning and Curvature in Human and Viral Proteins. J Phys Chem B 2020; 124:7574-7585. [PMID: 32813532 PMCID: PMC7476027 DOI: 10.1021/acs.jpcb.0c03435] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
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Membrane
proteins and lipids have the capacity to associate into
lateral domains in cell membranes through mutual or collective interactions.
Lipid rafts are functional lateral domains that are formed through
collective interactions of certain lipids and which can include or
exclude proteins. These domains have been implicated in cell signaling
and protein trafficking and seem to be of importance for virus–host
interactions. We therefore want to investigate if raft and viral membrane
proteins present similar structural features, and how these features
are distributed throughout viruses. For this purpose, we performed
a bioinformatics analysis of raft and viral membrane proteins from
available online databases and compared them to nonraft proteins.
In general, transmembrane proteins of rafts and viruses had higher
proportions of palmitoyl and phosphoryl residues compared to nonraft
proteins. They differed in terms of transmembrane domain length and
thickness, with viral proteins being generally shorter and having
a smaller accessible surface area per residue. Nontransmembrane raft
proteins had increased amounts of palmitoyl, prenyl, and phosphoryl
moieties while their viral counterparts were largely myristoylated
and phosphorylated. Several of these structural determinants such
as phosphorylation are new to the raft field and are extensively discussed
in terms of raft functionality and phase separation. Surprisingly,
the proportion of palmitoylated viral transmembrane proteins was inversely
correlated to the virus size which indicated the implication of palmitoylation
in virus membrane curvature and possibly budding. The current results
provide new insights into the raft–virus interplay and unveil
possible targets for antiviral compounds.
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Affiliation(s)
- Deniz Yurtsever
- Theoretical Biology and Bioinformatics, Department of Biology, Utrecht University, Padualaan 8, NL-3584CH Utrecht, The Netherlands
| | - Joseph Helmuth Lorent
- Membrane Biochemistry & Biophysics, Bijvoet Center for Biomolecular Research, Department of Chemistry, Utrecht University, Padualaan 8, NL-3584CH Utrecht, The Netherlands
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5
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Klinker S, Stindt S, Gremer L, Bode JG, Gertzen CGW, Gohlke H, Weiergräber OH, Hoffmann S, Willbold D. Phosphorylated tyrosine 93 of hepatitis C virus nonstructural protein 5A is essential for interaction with host c-Src and efficient viral replication. J Biol Chem 2019; 294:7388-7402. [PMID: 30862675 DOI: 10.1074/jbc.ra119.007656] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 03/11/2019] [Indexed: 12/23/2022] Open
Abstract
The hepatitis C virus (HCV) nonstructural protein 5A (NS5A) plays a key role in viral replication and virion assembly, and the regulation of the assembly process critically depends on phosphorylation of both serine and threonine residues in NS5A. We previously identified SRC proto-oncogene, nonreceptor tyrosine kinase (c-Src), as an essential host component of the HCV replication complex consisting of NS5A, the RNA-dependent RNA polymerase NS5B, and c-Src. Pulldown assays revealed an interaction between NS5A and the Src homology 2 (SH2) domain of c-Src; however, the precise binding mode remains undefined. In this study, using a variety of biochemical and biophysical techniques, along with molecular dynamics simulations, we demonstrate that the interaction between NS5A and the c-Src SH2 domain strictly depends on an intact phosphotyrosine-binding competent SH2 domain and on tyrosine phosphorylation within NS5A. Detailed analysis of c-Src SH2 domain binding to a panel of phosphorylation-deficient NS5A variants revealed that phosphorylation of Tyr-93 located within domain 1 of NS5A, but not of any other tyrosine residue, is crucial for complex formation. In line with these findings, effective replication of subgenomic HCV replicons as well as production of infectious virus particles in mammalian cell culture models were clearly dependent on the presence of tyrosine at position 93 of NS5A. These findings indicate that phosphorylated Tyr-93 in NS5A plays an important role during viral replication by facilitating NS5A's interaction with the SH2 domain of c-Src.
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Affiliation(s)
- Stefan Klinker
- From the Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40204 Düsseldorf
| | - Sabine Stindt
- the Department of Gastroenterology, Hepatology and Infectiology, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf
| | - Lothar Gremer
- From the Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40204 Düsseldorf.,the Institute of Complex Systems: Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich
| | - Johannes G Bode
- the Department of Gastroenterology, Hepatology and Infectiology, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf
| | - Christoph G W Gertzen
- the Institute of Complex Systems: Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich.,the John von Neumann Institute for Computing (NIC) and Jülich Supercomputing Centre (JSC), Forschungszentrum Jülich, 52425 Jülich, and.,the Institute for Pharmaceutical and Medicinal Chemistry, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Holger Gohlke
- the Institute of Complex Systems: Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich.,the John von Neumann Institute for Computing (NIC) and Jülich Supercomputing Centre (JSC), Forschungszentrum Jülich, 52425 Jülich, and.,the Institute for Pharmaceutical and Medicinal Chemistry, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Oliver H Weiergräber
- the Institute of Complex Systems: Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich
| | - Silke Hoffmann
- the Institute of Complex Systems: Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich
| | - Dieter Willbold
- From the Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40204 Düsseldorf, .,the Institute of Complex Systems: Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich
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6
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Hou L, Zhao J, Gao S, Ji T, Song T, Li Y, Wang J, Geng C, Long M, Chen J, Lin H, Cai X, Cang Y. Restriction of hepatitis B virus replication by c-Abl-induced proteasomal degradation of the viral polymerase. SCIENCE ADVANCES 2019; 5:eaau7130. [PMID: 30775435 PMCID: PMC6365112 DOI: 10.1126/sciadv.aau7130] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Accepted: 12/19/2018] [Indexed: 05/13/2023]
Abstract
About 257 million people with chronic infection of hepatitis B virus (HBV) worldwide are at high risk of developing terminal liver diseases. Reactivation of virus replication has been frequently reported in those patient populations receiving imatinib (an Abl kinase inhibitor) or bortezomib (a proteasome inhibitor) to treat concurrent diseases, but the underlying mechanism for this reactivation is unknown. We report that the HBV polymerase protein is recruited by Cdt2 to the cullin-RING ligase 4 (CRL4) for ubiquitination and proteasome degradation and that this process is stimulated by the c-Abl nonreceptor tyrosine kinase. Genetic ablation of the Abl-CRL4Cdt2 axis or pharmaceutical inhibition of this process stabilizes HBV polymerase protein and increases viral loads in HBV-infected liver cancer cell lines. Our study reveals a kinase-dependent activation of CRL4 ubiquitin ligase that can be targeted for blocking HBV replication.
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Affiliation(s)
- Lidan Hou
- Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang 310058, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Jie Zhao
- Department of General Surgery, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Shaobing Gao
- Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang 310058, China
- Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou, Henan 450008, China
| | - Tong Ji
- Department of General Surgery, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Tianyu Song
- Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang 310058, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Yining Li
- Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Jingjie Wang
- Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Chenlu Geng
- Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Min Long
- Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Jiang Chen
- Department of General Surgery, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Hui Lin
- Department of General Surgery, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Xiujun Cai
- Department of General Surgery, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Yong Cang
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
- Corresponding author.
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7
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Sisk JM, Frieman MB, Machamer CE. Coronavirus S protein-induced fusion is blocked prior to hemifusion by Abl kinase inhibitors. J Gen Virol 2018; 99:619-630. [PMID: 29557770 DOI: 10.1099/jgv.0.001047] [Citation(s) in RCA: 108] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Enveloped viruses gain entry into host cells by fusing with cellular membranes, a step that is required for virus replication. Coronaviruses, including the severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV) and infectious bronchitis virus (IBV), fuse at the plasma membrane or use receptor-mediated endocytosis and fuse with endosomes, depending on the cell or tissue type. The virus spike (S) protein mediates fusion with the host cell membrane. We have shown previously that an Abelson (Abl) kinase inhibitor, imatinib, significantly reduces SARS-CoV and MERS-CoV viral titres and prevents endosomal entry by HIV SARS S and MERS S pseudotyped virions. SARS-CoV and MERS-CoV are classified as BSL-3 viruses, which makes experimentation into the cellular mechanisms involved in infection more challenging. Here, we use IBV, a BSL-2 virus, as a model for studying the role of Abl kinase activity during coronavirus infection. We found that imatinib and two specific Abl kinase inhibitors, GNF2 and GNF5, reduce IBV titres by blocking the first round of virus infection. Additionally, all three drugs prevented IBV S-induced syncytia formation prior to the hemifusion step. Our results indicate that membrane fusion (both virus-cell and cell-cell) is blocked in the presence of Abl kinase inhibitors. Studying the effects of Abl kinase inhibitors on IBV will be useful in identifying the host cell pathways required for coronavirus infection. This will provide an insight into possible therapeutic targets to treat infections by current as well as newly emerging coronaviruses.
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Affiliation(s)
- Jeanne M Sisk
- Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Matthew B Frieman
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Carolyn E Machamer
- Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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8
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Dual inhibitors of hepatitis C virus and hepatocellular carcinoma: design, synthesis and docking studies. Future Sci OA 2017; 4:FSO252. [PMID: 29255624 PMCID: PMC5729604 DOI: 10.4155/fsoa-2017-0075] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 09/11/2017] [Indexed: 01/06/2023] Open
Abstract
Aim Simultaneous inhibition of hepatitis C virus (HCV) and hepatocellular carcinoma (HCC) may enhance anti-HCV effects and reduce resistance and side effects. Results/methodology Novel hybrid derivatives were designed and synthesized to exhibit dual activity against HCV and its associated major complication, HCC. The synthesized compounds were screened for their potential activity against HCV and HCC. Compounds 5f, 5j, 5l, 5p, 5q, 5r, 6c and 6d exhibited potential in vitro anticancer activity against HCC cell line HepG2, while compounds 5a, 5l, 5p and 5v showed in vitro anti-HCV activity. Docking studies suggested that the newly synthesized compounds could suppress HCC through VEGFR2 tyrosine kinase inhibition. Conclusion Compounds 5l and 5p exhibited dual activity against HCV and HCC in vitro.
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9
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Mishchenko EL, Petrovskaya OV, Mishchenko AM, Petrovskiy ED, Ivanisenko NV, Ivanisenko VA. Integrated mathematical models for describing complex biological processes. Biophysics (Nagoya-shi) 2017. [DOI: 10.1134/s0006350917050141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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10
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STAT1 is essential for the inhibition of hepatitis C virus replication by interferon-λ but not by interferon-α. Sci Rep 2016; 6:38336. [PMID: 27929099 PMCID: PMC5144079 DOI: 10.1038/srep38336] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Accepted: 11/08/2016] [Indexed: 12/21/2022] Open
Abstract
Interferon-α (IFN-α) and IFN-λ are structurally distinct cytokines that bind to different receptors, but induce expression of similar sets of genes through Janus kinase (JAK)-signal transducers and activators of transcription (STAT) pathways. The difference between IFN-α and IFN-λ signaling remains poorly understood. Here, using the CRISPR/Cas9 system, we examine the role of STAT1 and STAT2 in the inhibition of hepatitis C virus (HCV) replication by IFN-α and IFN-λ. Treatment with IFN-α increases expression of IFN-stimulated genes (ISGs) such as double-stranded RNA-activated protein kinase (PKR) and decreases viral RNA and protein levels in HCV-infected Huh-7.5 human hepatoma cells. These responses are only partially attenuated by knockout of STAT1 but are abolished by knockout of STAT2. In contrast, the inhibition of HCV replication by IFN-λ is abolished by knockout of STAT1 or STAT2. Microarray analysis reveals that IFN-α but not IFN-λ can induce expression of the majority of ISGs in STAT1 knockout cells. These findings suggest that IFN-α can inhibit HCV replication through a STAT2-dependent but STAT1-independent pathway, whereas IFN-λ induces ISG expression and inhibits HCV replication exclusively through a STAT1- and STAT2-dependent pathway.
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Abstract
The Abelson tyrosine kinases were initially identified as drivers of leukemia in mice and humans. The Abl family kinases Abl1 and Abl2 regulate diverse cellular processes during development and normal homeostasis, and their functions are subverted during inflammation, cancer and other pathologies. Abl kinases can be activated by multiple stimuli leading to cytoskeletal reorganization required for cell morphogenesis, motility, adhesion and polarity. Depending on the cellular context, Abl kinases regulate cell survival and proliferation. Emerging data support important roles for Abl kinases in pathologies linked to inflammation. Among these are neurodegenerative diseases and inflammatory pathologies. Unexpectedly, Abl kinases have also been identified as important players in mammalian host cells during microbial pathogenesis. Thus, the use of Abl kinase inhibitors might prove to be effective in the treatment of pathologies beyond leukemia and solid tumors. In this Cell Science at a Glance article and in the accompanying poster, we highlight the emerging roles of Abl kinases in the regulation of cellular processes in normal cells and diverse pathologies ranging from cancer to microbial pathogenesis.
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Affiliation(s)
- Aaditya Khatri
- Department of Pharmacology & Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Jun Wang
- Department of Pharmacology & Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Ann Marie Pendergast
- Department of Pharmacology & Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
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12
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Secci E, Luchinat E, Banci L. The Casein Kinase 2-Dependent Phosphorylation of NS5A Domain 3 from Hepatitis C Virus Followed by Time-Resolved NMR Spectroscopy. Chembiochem 2016; 17:328-33. [PMID: 26684216 DOI: 10.1002/cbic.201500551] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2015] [Indexed: 12/19/2022]
Abstract
Hepatitis C virus (HCV) chronically affects millions of individuals worldwide. The HCV nonstructural protein 5A (NS5A) plays a critical role in the viral assembly pathway. Domain 3 (D3) of NS5A is an unstructured polypeptide responsible for the interaction with the core particle assembly structure. Casein kinase 2 (CK2) phosphorylates NS5A-D3 at multiple sites that have mostly been predicted and only observed indirectly. In order to identify the CK2-dependent phosphorylation sites, we monitored the reaction between NS5A-D3 and CK2 in vitro by time-resolved NMR. We unambiguously identified four serine residues as substrates of CK2. The apparent rate constant for each site was determined from the reaction curves. Ser408 was quickly phosphorylated, whereas the three other serine residues reacted more slowly. These results provide a starting point from which to elucidate the role of phosphorylation in the mechanisms of viral assembly-and in the modulation of the viral activity-at the molecular level.
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Affiliation(s)
- Erica Secci
- Magnetic Resonance Center-CERM, University of Florence, via Luigi Sacconi 6, 50019 Sesto Fiorentino, Florence, Italy
| | - Enrico Luchinat
- Magnetic Resonance Center-CERM, University of Florence, via Luigi Sacconi 6, 50019 Sesto Fiorentino, Florence, Italy.,Department of Biomedical, Experimental and Clinical Sciences, University of Florence, viale Morgagni 50, 50134, Florence, Italy
| | - Lucia Banci
- Magnetic Resonance Center-CERM, University of Florence, via Luigi Sacconi 6, 50019 Sesto Fiorentino, Florence, Italy. .,Department of Chemistry, University of Florence, via della Lastruccia 3, 50019 Sesto Fiorentino, Florence, Italy.
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Phosphorylation of Single Stranded RNA Virus Proteins and Potential for Novel Therapeutic Strategies. Viruses 2015; 7:5257-73. [PMID: 26473910 PMCID: PMC4632380 DOI: 10.3390/v7102872] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2015] [Revised: 09/23/2015] [Accepted: 09/29/2015] [Indexed: 12/31/2022] Open
Abstract
Post translational modification of proteins is a critical requirement that regulates function. Among the diverse kinds of protein post translational modifications, phosphorylation plays essential roles in protein folding, protein:protein interactions, signal transduction, intracellular localization, transcription regulation, cell cycle progression, survival and apoptosis. Protein phosphorylation is also essential for many intracellular pathogens to establish a productive infection cycle. Preservation of protein phosphorylation moieties in pathogens in a manner that mirrors the host components underscores the co-evolutionary trajectory of pathogens and hosts, and sheds light on how successful pathogens have usurped, either in part or as a whole, the host enzymatic machinery. Phosphorylation of viral proteins for many acute RNA viruses including Flaviviruses and Alphaviruses has been demonstrated to be critical for protein functionality. This review focuses on phosphorylation modifications that have been documented to occur on viral proteins with emphasis on acutely infectious, single stranded RNA viruses. The review additionally explores the possibility of repurposing Food and Drug Administration (FDA) approved inhibitors as antivirals for the treatment of acute RNA viral infections.
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