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Alternative splicing liberates a cryptic cytoplasmic isoform of mitochondrial MECR that antagonizes influenza virus. PLoS Biol 2022; 20:e3001934. [PMID: 36542656 PMCID: PMC9815647 DOI: 10.1371/journal.pbio.3001934] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 01/05/2023] [Accepted: 11/29/2022] [Indexed: 12/24/2022] Open
Abstract
Viruses must balance their reliance on host cell machinery for replication while avoiding host defense. Influenza A viruses are zoonotic agents that frequently switch hosts, causing localized outbreaks with the potential for larger pandemics. The host range of influenza virus is limited by the need for successful interactions between the virus and cellular partners. Here we used immunocompetitive capture-mass spectrometry to identify cellular proteins that interact with human- and avian-style viral polymerases. We focused on the proviral activity of heterogenous nuclear ribonuclear protein U-like 1 (hnRNP UL1) and the antiviral activity of mitochondrial enoyl CoA-reductase (MECR). MECR is localized to mitochondria where it functions in mitochondrial fatty acid synthesis (mtFAS). While a small fraction of the polymerase subunit PB2 localizes to the mitochondria, PB2 did not interact with full-length MECR. By contrast, a minor splice variant produces cytoplasmic MECR (cMECR). Ectopic expression of cMECR shows that it binds the viral polymerase and suppresses viral replication by blocking assembly of viral ribonucleoprotein complexes (RNPs). MECR ablation through genome editing or drug treatment is detrimental for cell health, creating a generic block to virus replication. Using the yeast homolog Etr1 to supply the metabolic functions of MECR in MECR-null cells, we showed that specific antiviral activity is independent of mtFAS and is reconstituted by expressing cMECR. Thus, we propose a strategy where alternative splicing produces a cryptic antiviral protein that is embedded within a key metabolic enzyme.
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Gundogdu R, Hergovich A. MOB (Mps one Binder) Proteins in the Hippo Pathway and Cancer. Cells 2019; 8:cells8060569. [PMID: 31185650 PMCID: PMC6627106 DOI: 10.3390/cells8060569] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 06/03/2019] [Accepted: 06/04/2019] [Indexed: 12/22/2022] Open
Abstract
The family of MOBs (monopolar spindle-one-binder proteins) is highly conserved in the eukaryotic kingdom. MOBs represent globular scaffold proteins without any known enzymatic activities. They can act as signal transducers in essential intracellular pathways. MOBs have diverse cancer-associated cellular functions through regulatory interactions with members of the NDR/LATS kinase family. By forming additional complexes with serine/threonine protein kinases of the germinal centre kinase families, other enzymes and scaffolding factors, MOBs appear to be linked to an even broader disease spectrum. Here, we review our current understanding of this emerging protein family, with emphases on post-translational modifications, protein-protein interactions, and cellular processes that are possibly linked to cancer and other diseases. In particular, we summarise the roles of MOBs as core components of the Hippo tissue growth and regeneration pathway.
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Affiliation(s)
- Ramazan Gundogdu
- Vocational School of Health Services, Bingol University, 12000 Bingol, Turkey.
| | - Alexander Hergovich
- UCL Cancer Institute, University College London, WC1E 6BT, London, United Kingdom.
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Farooq QUA, Khan FF. Construction and analysis of a comprehensive protein interaction network of HCV with its host Homo sapiens. BMC Infect Dis 2019; 19:367. [PMID: 31039741 PMCID: PMC6492420 DOI: 10.1186/s12879-019-4000-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 04/17/2019] [Indexed: 12/24/2022] Open
Abstract
Background Hepatitis C Virus is becoming a major health problem in Asia and across the globe since it is causing serious liver diseases including liver cirrhosis, chronic hepatitis and hepatocarcinoma (HCC). Protein interaction networks presents us innumerable novel insights into functional constitution of proteome and helps us finding potential candidates for targeting the drugs. Methods Here we present a comprehensive protein interaction network of Hepatitis C Virus with its host, constructed by literature curated interactions. The network was constructed and explored using Cytoscape and the results were further analyzed using KEGG pathway, Gene Ontology enrichment analysis and MCODE. Results We found 1325 interactions between 12 HCV proteins and 940 human genes, among which 21 were intraviral and 1304 were HCV-Human. By analyzing the network, we found potential human gene list with their number of interactions with HCV proteins. ANXA2 and NR4A1 were interacting with 6 HCV proteins while we found 11 human genes which were interacting with 5 HCV proteins. Furthermore, the enrichment analysis and Gene Ontology of the top genes to find the pathways and the biological processes enriched with those genes. Among the viral proteins, NS3 was interacting with most number of interactors followed by NS5A and so on. KEGG pathway analysis of three set of most HCV- associated human genes was performed to find out which gene products are involved in certain disease pathways. Top 5, 10 and 20 human genes with most interactions were analyzed which revealed some striking results among which the top 10 host genes came up to be significant because they were more related to Influenza A viral infection previously. This insight provides us with a clue that the set of genes are highly enriched in HCV but are not well studied in its infection pathway. Conclusions We found out a group of proteins which were rich in HCV viral pathway but there were no drugs targeting them according to the drug repurposing hub. It can be concluded that the cluster we obtained from MCODE contains potential targets for HCV treatment and could be implemented for molecular docking and drug designing further by the scientists.
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Affiliation(s)
- Qurat Ul Ain Farooq
- College of Life Sciences and Bio Engineering, Beijing University of Technology, Beijing, China.
| | - Faisal F Khan
- Institute of Integrative Biosciences, CECOS University of IT and Emerging Sciences, Peshawar, Pakistan
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Yokota H. Applications of proteomics in pharmaceutical research and development. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2018; 1867:17-21. [PMID: 29753086 DOI: 10.1016/j.bbapap.2018.05.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 04/10/2018] [Accepted: 05/08/2018] [Indexed: 01/13/2023]
Abstract
The significance of proteomics in the pharmaceutical industry has increased since overcoming initial difficulties. This review discusses recent proteomics publications from pharmaceutical companies to identify new trends in proteomics applications to research and development. Applications of proteomics such as chemical proteomics, protein expression profiling, targeted protein quantitation, analysis of protein-protein interactions and post-translational modification are widely used by various sections of the industry. Technological advancements in proteomics will further accelerate pharmaceutical research and development.
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Affiliation(s)
- Hiroyuki Yokota
- Astellas Pharma Inc., 21 Miyukigaoka, Tsukuba-shi 305-8585, Japan.
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Sharif AA, Hergovich A. The NDR/LATS protein kinases in immunology and cancer biology. Semin Cancer Biol 2018; 48:104-114. [DOI: 10.1016/j.semcancer.2017.04.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 03/15/2017] [Accepted: 04/25/2017] [Indexed: 02/07/2023]
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6
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HtrA1 Mediated Intracellular Effects on Tubulin Using a Polarized RPE Disease Model. EBioMedicine 2017; 27:258-274. [PMID: 29269042 PMCID: PMC5828370 DOI: 10.1016/j.ebiom.2017.12.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 12/08/2017] [Accepted: 12/11/2017] [Indexed: 12/18/2022] Open
Abstract
Age-related macular degeneration (AMD) is the leading cause of irreversible vision loss. The protein HtrA1 is enriched in retinal pigment epithelial (RPE) cells isolated from AMD patients and in drusen deposits. However, it is poorly understood how increased levels of HtrA1 affect the physiological function of the RPE at the intracellular level. Here, we developed hfRPE (human fetal retinal pigment epithelial) cell culture model where cells fully differentiated into a polarized functional monolayer. In this model, we fine-tuned the cellular levels of HtrA1 by targeted overexpression. Our data show that HtrA1 enzymatic activity leads to intracellular degradation of tubulin with a corresponding reduction in the number of microtubules, and consequently to an altered mechanical cell phenotype. HtrA1 overexpression further leads to impaired apical processes and decreased phagocytosis, an essential function for photoreceptor survival. These cellular alterations correlate with the AMD phenotype and thus highlight HtrA1 as an intracellular target for therapeutic interventions towards AMD treatment.
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Lugert S, Kremer T, Jagasia R, Herrmann A, Aigner S, Giachino C, Mendez-David I, Gardier AM, Carralot JP, Meistermann H, Augustin A, Saxe MD, Lamerz J, Duran-Pacheco G, Ducret A, Taylor V, David DJ, Czech C. Glypican-2 levels in cerebrospinal fluid predict the status of adult hippocampal neurogenesis. Sci Rep 2017; 7:46543. [PMID: 28440309 PMCID: PMC5404329 DOI: 10.1038/srep46543] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 03/17/2017] [Indexed: 12/20/2022] Open
Abstract
Adult hippocampal neurogenesis is a remarkable form of brain plasticity through which new neurons are generated throughout life. Despite its important roles in cognition and emotion and its modulation in various preclinical disease models, the functional importance of adult hippocampal neurogenesis in human health has not been revealed because of a lack of tools for monitoring adult neurogenesis in vivo. Therefore, we performed an unbiased proteomics screen to identify novel proteins expressed during neuronal differentiation using a human neural stem cell model, and we identified the proteoglycan Glypican-2 (Gpc2) as a putative secreted marker of immature neurons. Exogenous Gpc2 binds to FGF2 and inhibits FGF2-induced neural progenitor cell proliferation. Gpc2 is enriched in neurogenic regions of the adult brain. Its expression is increased by physiological stimuli that increase hippocampal neurogenesis and decreased in transgenic models in which neurogenesis is selectively ablated. Changes in neurogenesis also result in changes in Gpc2 protein level in cerebrospinal fluid (CSF). Gpc2 is detectable in adult human CSF, and first pilot experiments with a longitudinal cohort indicate a decrease over time. Thus, Gpc2 may serve as a potential marker to monitor adult neurogenesis in both animal and human physiology and disease, warranting future studies.
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Affiliation(s)
- S Lugert
- Roche Pharmaceutical Research and Early Development, NORD Discovery &Translational Area, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - T Kremer
- Roche Pharmaceutical Research and Early Development, NORD Discovery &Translational Area, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - R Jagasia
- Roche Pharmaceutical Research and Early Development, NORD Discovery &Translational Area, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - A Herrmann
- Roche Pharmaceutical Research and Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - S Aigner
- Roche Pharmaceutical Research and Early Development, NORD Discovery &Translational Area, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - C Giachino
- Embryology and Stem Cell Biology, Department of Biomedicine, University of Basel, Mattenstrasse 28, CH-4058 Basel, Switzerland
| | - I Mendez-David
- CESP/UMR-S 1178, Univ. Paris-Sud, Fac. Pharmacie, INSERM, Université Paris-Saclay, Chatenay Malabry, 92290, France
| | - A M Gardier
- CESP/UMR-S 1178, Univ. Paris-Sud, Fac. Pharmacie, INSERM, Université Paris-Saclay, Chatenay Malabry, 92290, France
| | - J P Carralot
- Roche Pharmaceutical Research and Early Development, Therapeutic Modalities, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - H Meistermann
- Roche Pharmaceutical Research and Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - A Augustin
- Roche Pharmaceutical Research and Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - M D Saxe
- Roche Pharmaceutical Research and Early Development, NORD Discovery &Translational Area, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - J Lamerz
- Roche Pharmaceutical Research and Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - G Duran-Pacheco
- Roche Pharmaceutical Research and Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - A Ducret
- Roche Pharmaceutical Research and Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - V Taylor
- Embryology and Stem Cell Biology, Department of Biomedicine, University of Basel, Mattenstrasse 28, CH-4058 Basel, Switzerland
| | - D J David
- CESP/UMR-S 1178, Univ. Paris-Sud, Fac. Pharmacie, INSERM, Université Paris-Saclay, Chatenay Malabry, 92290, France
| | - C Czech
- Roche Pharmaceutical Research and Early Development, NORD Discovery &Translational Area, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070 Basel, Switzerland
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Ivanenkov YA, Aladinskiy VA, Bushkov NA, Ayginin AA, Majouga AG, Ivachtchenko AV. Small-molecule inhibitors of hepatitis C virus (HCV) non-structural protein 5A (NS5A): a patent review (2010-2015). Expert Opin Ther Pat 2017; 27:401-414. [PMID: 27967269 DOI: 10.1080/13543776.2017.1272573] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
INTRODUCTION Non-structural 5A (NS5A) protein has achieved a considerable attention as an attractive target for the treatment of hepatitis C (HCV). A number of novel NS5A inhibitors have been reported to date. Several drugs having favorable ADME properties and mild side effects were launched into the pharmaceutical market. For instance, daclatasvir was launched in 2014, elbasvir is currently undergoing registration, ledipasvir was launched in 2014 as a fixed-dose combination with sofosbuvir (NS5B inhibitor). Areas covered: Thomson integrity database and SciFinder database were used as a valuable source to collect the patents on small-molecule NS5A inhibitors. All the structures were ranked by the date of priority. Patent holder and antiviral activity for each scaffold claimed were summarized and presented in a convenient manner. A particular focus was placed on the best-in-class bis-pyrrolidine-containing NS5A inhibitors. Expert opinion: Several first generation NS5A inhibitors have recently progressed into advanced clinical trials and showed superior efficacy in reducing viral load in infected subjects. Therapy schemes of using these agents in combination with other established antiviral drugs with complementary mechanisms of action can address the emergence of resistance and poor therapeutic outcome frequently attributed to antiviral drugs.
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Affiliation(s)
- Yan A Ivanenkov
- a Department of Biological and Medical Physics , Moscow Institute of Physics and Technology (State University) , Dolgoprudny City , Moscow Region , Russia.,b Department of Computational and Medicinal Chemistry , ChemDiv , San Diego , CA , USA.,c Chemistry Department , Moscow State University , Moscow , Russia
| | - Vladimir A Aladinskiy
- a Department of Biological and Medical Physics , Moscow Institute of Physics and Technology (State University) , Dolgoprudny City , Moscow Region , Russia
| | - Nikolay A Bushkov
- a Department of Biological and Medical Physics , Moscow Institute of Physics and Technology (State University) , Dolgoprudny City , Moscow Region , Russia
| | - Andrey A Ayginin
- a Department of Biological and Medical Physics , Moscow Institute of Physics and Technology (State University) , Dolgoprudny City , Moscow Region , Russia
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Vandemoortele G, Gevaert K, Eyckerman S. Proteomics in the genome engineering era. Proteomics 2015; 16:177-87. [DOI: 10.1002/pmic.201500262] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 09/22/2015] [Accepted: 10/15/2015] [Indexed: 12/13/2022]
Affiliation(s)
- Giel Vandemoortele
- VIB Medical Biotechnology Center; Ghent Belgium
- Department of Biochemistry; Ghent University; Ghent Belgium
| | - Kris Gevaert
- VIB Medical Biotechnology Center; Ghent Belgium
- Department of Biochemistry; Ghent University; Ghent Belgium
| | - Sven Eyckerman
- VIB Medical Biotechnology Center; Ghent Belgium
- Department of Biochemistry; Ghent University; Ghent Belgium
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Fredolini C, Byström S, Pin E, Edfors F, Tamburro D, Iglesias MJ, Häggmark A, Hong MG, Uhlen M, Nilsson P, Schwenk JM. Immunocapture strategies in translational proteomics. Expert Rev Proteomics 2015; 13:83-98. [PMID: 26558424 PMCID: PMC4732419 DOI: 10.1586/14789450.2016.1111141] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Aiming at clinical studies of human diseases, antibody-assisted assays have been applied to biomarker discovery and toward a streamlined translation from patient profiling to assays supporting personalized treatments. In recent years, integrated strategies to couple and combine antibodies with mass spectrometry-based proteomic efforts have emerged, allowing for novel possibilities in basic and clinical research. Described in this review are some of the field's current and emerging immunocapture approaches from an affinity proteomics perspective. Discussed are some of their advantages, pitfalls and opportunities for the next phase in clinical and translational proteomics.
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Affiliation(s)
- Claudia Fredolini
- Affinity Proteomics, SciLifeLab, School of Biotechnology, KTH - Royal Institute of Technology, Solna, Sweden
| | - Sanna Byström
- Affinity Proteomics, SciLifeLab, School of Biotechnology, KTH - Royal Institute of Technology, Solna, Sweden
| | - Elisa Pin
- Affinity Proteomics, SciLifeLab, School of Biotechnology, KTH - Royal Institute of Technology, Solna, Sweden
| | - Fredrik Edfors
- Affinity Proteomics, SciLifeLab, School of Biotechnology, KTH - Royal Institute of Technology, Solna, Sweden
| | - Davide Tamburro
- Department of Oncology-Pathology, Clinical Proteomics Mass Spectrometry, SciLifeLab, Karolinska Institutet, Solna, Sweden
| | - Maria Jesus Iglesias
- Affinity Proteomics, SciLifeLab, School of Biotechnology, KTH - Royal Institute of Technology, Solna, Sweden
| | - Anna Häggmark
- Affinity Proteomics, SciLifeLab, School of Biotechnology, KTH - Royal Institute of Technology, Solna, Sweden
| | - Mun-Gwan Hong
- Affinity Proteomics, SciLifeLab, School of Biotechnology, KTH - Royal Institute of Technology, Solna, Sweden
| | - Mathias Uhlen
- Affinity Proteomics, SciLifeLab, School of Biotechnology, KTH - Royal Institute of Technology, Solna, Sweden
| | - Peter Nilsson
- Affinity Proteomics, SciLifeLab, School of Biotechnology, KTH - Royal Institute of Technology, Solna, Sweden
| | - Jochen M Schwenk
- Affinity Proteomics, SciLifeLab, School of Biotechnology, KTH - Royal Institute of Technology, Solna, Sweden
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Douam F, Ploss A. Proteomic approaches to analyzing hepatitis C virus biology. Proteomics 2015; 15:2051-65. [PMID: 25809442 PMCID: PMC4559851 DOI: 10.1002/pmic.201500009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 02/25/2015] [Accepted: 03/19/2015] [Indexed: 12/15/2022]
Abstract
Hepatitis C virus (HCV) is a major cause of liver disease worldwide. Acute infection often progresses to chronicity resulting frequently in fibrosis, cirrhosis, and in rare cases, in the development of hepatocellular carcinoma. Although HCV has proven to be an arduous object of research and has raised important technical challenges, several experimental models have been developed all over the last two decades in order to improve our understanding of the virus life cycle, pathogenesis and virus-host interactions. The recent development of direct acting-agents, leading to considerable progress in treatment of patients, represents the direct outcomes of these achievements. Proteomic approaches have been of critical help to shed light on several aspect of the HCV biology such as virion composition, viral replication, and virus assembly and to unveil diagnostic or prognostic markers of HCV-induced liver disease. Here, we review how proteomic approaches have led to improve our understanding of HCV life cycle and liver disease, thus highlighting the relevance of these approaches for studying the complex interactions between other challenging human viral pathogens and their host.
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Affiliation(s)
- Florian Douam
- Department of Molecular Biology, Princeton University, 110 Lewis Thomas Laboratory, Washington Road, Princeton, NJ 08544
| | - Alexander Ploss
- Department of Molecular Biology, Princeton University, 110 Lewis Thomas Laboratory, Washington Road, Princeton, NJ 08544
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Masaki T, Suzuki T. NS5A phosphorylation: its functional role in the life cycle of hepatitis C virus. Future Virol 2015. [DOI: 10.2217/fvl.15.33] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
ABSTRACT Hepatitis C virus (HCV) is a major cause of liver disease. HCV RNA replicates in a membrane-associated replication complex. Nonstructural protein 5A (NS5A) is phosphorylated on multiple serine and threonine residues and exists in basally phosphorylated and hyperphosphorylated forms. To date, studies have identified several serine/threonine kinases responsible for NS5A phosphorylation. Although NS5A has no known enzymatic activity, it is a multifunctional protein required for HCV RNA replication and virion assembly. The phosphorylation status of NS5A is considered to have a significant impact on its function and the viral life cycle. Furthermore, NS5A inhibitors represent a new class of direct acting antivirals and have become a key component for effective combination therapies against HCV infection.
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Affiliation(s)
- Takahiro Masaki
- Department of Virology II, National Institute of Infectious Diseases, Tokyo 162-8640, Japan
| | - Tetsuro Suzuki
- Department of Infectious Diseases, Hamamatsu University School of Medicine, Shizuoka 431-3192, Japan
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Bacarizo J, Martínez-Rodríguez S, Cámara-Artigas A. Structure of the c-Src-SH3 domain in complex with a proline-rich motif of NS5A protein from the hepatitis C virus. J Struct Biol 2014; 189:67-72. [PMID: 25447263 DOI: 10.1016/j.jsb.2014.11.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Revised: 11/14/2014] [Accepted: 11/18/2014] [Indexed: 10/24/2022]
Abstract
The non-structural hepatitis C virus proteins NS5A and NS5B form a complex through interaction with the SH2 and SH3 domains of the non-receptor Src tyrosine kinase, which seems essential for viral replication. We have crystallized the complex between the SH3 domain of the c-Src tyrosine kinase and the C-terminal proline rich motif of the NS5A protein (A349PPIPPPRRKR359). Crystals obtained at neutral pH belong to the space group I41, with a single molecule of the SH3/NS5A complex at the asymmetric unit. The NS5A peptide is bound in a reverse orientation (class II) and the comparison of this structure with those of the high affinity synthetic peptides APP12 and VSL12 shows some important differences at the salt bridge that drives the peptide orientation. Further conformational changes in residues placed apart from the binding site also seem to play an important role in the binding orientation of this peptide. Our results show the interaction of the SH3 domain of the c-Src tyrosine kinase with a proline rich motif in the NS5A protein and point to their potential interaction in vivo.
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Affiliation(s)
- Julio Bacarizo
- Department of Chemistry and Physics, University of Almería, Agrifood Campus of International Excellence (ceiA3), Carretera de Sacramento s/n, Almería 04120, Spain
| | - Sergio Martínez-Rodríguez
- Department of Physical Chemistry, University of Granada, Avda. de Fuentenueva s/n, Granada 18071, Spain
| | - Ana Cámara-Artigas
- Department of Chemistry and Physics, University of Almería, Agrifood Campus of International Excellence (ceiA3), Carretera de Sacramento s/n, Almería 04120, Spain.
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