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Devantier K, Kjær VMS, Griffin S, Kragelund BB, Rosenkilde MM. Advancing the field of viroporins-Structure, function and pharmacology: IUPHAR Review X. Br J Pharmacol 2024. [PMID: 39224966 DOI: 10.1111/bph.17317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 06/28/2024] [Accepted: 07/07/2024] [Indexed: 09/04/2024] Open
Abstract
Viroporins possess important potential as antiviral targets due to their critical roles during virus life cycles, spanning from virus entry to egress. Although the antiviral amantadine targets the M2 viroporin of influenza A virus, successful progression of other viroporin inhibitors into clinical use remains challenging. These challenges relate in varying proportions to a lack of reliable full-length 3D-structures, difficulties in functionally characterising individual viroporins, and absence of verifiable direct binding between inhibitor and viroporin. This review offers perspectives to help overcome these challenges. We provide a comprehensive overview of the viroporin family, including their structural and functional features, highlighting the moldability of their energy landscapes and actions. To advance the field, we suggest a list of best practices to aspire towards unambiguous viroporin identification and characterisation, along with considerations of potential pitfalls. Finally, we present current and future scenarios of, and prospects for, viroporin targeting drugs.
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Affiliation(s)
- Kira Devantier
- Molecular and Translational Pharmacology, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
- Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Viktoria M S Kjær
- Molecular and Translational Pharmacology, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Stephen Griffin
- Leeds Institute of Medical Research, St James' University Hospital, School of Medicine, Faculty of Medicine and Health, University of Leeds, Leeds, UK
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, UK
| | - Birthe B Kragelund
- Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Mette M Rosenkilde
- Molecular and Translational Pharmacology, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
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2
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Arita M. An efficient trans complementation system for in vivo replication of defective poliovirus mutants. J Virol 2024; 98:e0052324. [PMID: 38837378 PMCID: PMC11265389 DOI: 10.1128/jvi.00523-24] [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] [Received: 03/19/2024] [Accepted: 05/13/2024] [Indexed: 06/07/2024] Open
Abstract
The picornavirus genome encodes a large, single polyprotein that is processed by viral proteases to form an active replication complex. The replication complex is formed with the viral genome, host proteins, and viral proteins that are produced/translated directly from each of the viral genomes (viral proteins provided in cis). Efficient complementation in vivo of replication complex formation by viral proteins provided in trans, thus exogenous or ectopically expressed viral proteins, remains to be demonstrated. Here, we report an efficient trans complementation system for the replication of defective poliovirus (PV) mutants by a viral polyprotein precursor in HEK293 cells. Viral 3AB in the polyprotein, but not 2BC, was processed exclusively in cis. Replication of a defective PV replicon mutant, with a disrupted cleavage site for viral 3Cpro protease between 3Cpro and 3Dpol (3C/D[A/G] mutant) could be rescued by a viral polyprotein provided in trans. Only a defect of 3Dpol activity of the replicon could be rescued in trans; inactivating mutations in 2CATPase/hel, 3B, and 3Cpro of the replicon completely abrogated the trans-rescued replication. An intact N-terminus of the 3Cpro domain of the 3CDpro provided in trans was essential for the trans-active function. By using this trans complementation system, a high-titer defective PV pseudovirus (PVpv) (>107 infectious units per mL) could be produced with the defective mutants, whose replication was completely dependent on trans complementation. This work reveals potential roles of exogenous viral proteins in PV replication and offers insights into protein/protein interaction during picornavirus infection. IMPORTANCE Viral polyprotein processing is an elaborately controlled step by viral proteases encoded in the polyprotein; fully processed proteins and processing intermediates need to be correctly produced for replication, which can be detrimentally affected even by a small modification of the polyprotein. Purified/isolated viral proteins can retain their enzymatic activities required for viral replication, such as protease, helicase, polymerase, etc. However, when these proteins of picornavirus are exogenously provided (provided in trans) to the viral replication complex with a defective viral genome, replication is generally not rescued/complemented, suggesting the importance of viral proteins endogenously provided (provided in cis) to the replication complex. In this study, I discovered that only the viral polymerase activity of poliovirus (PV) (the typical member of picornavirus family) could be efficiently rescued by exogenously expressed viral proteins. The current study reveals potential roles for exogenous viral proteins in viral replication and offers insights into interactions during picornavirus infection.
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Affiliation(s)
- Minetaro Arita
- Department of Virology II, National Institute of Infectious Diseases, Musashimurayama-shi, Tokyo, Japan
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3
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Asrani P, Seebohm G, Stoll R. Potassium viroporins as model systems for understanding eukaryotic ion channel behaviour. Virus Res 2022; 320:198903. [PMID: 36037849 DOI: 10.1016/j.virusres.2022.198903] [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: 03/14/2022] [Revised: 08/24/2022] [Accepted: 08/25/2022] [Indexed: 11/29/2022]
Abstract
Ion channels are membrane proteins essential for a plethora of cellular functions including maintaining cell shape, ion homeostasis, cardiac rhythm and action potential in neurons. The complexity and often extensive structure of eukaryotic membrane proteins makes it difficult to understand their basic biological regulation. Therefore, this article suggests, viroporins - the miniature versions of eukaryotic protein homologs from viruses - might serve as model systems to provide insights into behaviour of eukaryotic ion channels in general. The structural requirements for correct assembly of the channel along with the basic functional properties of a K+ channel exist in the minimal design of the viral K+ channels from two viruses, Chlorella virus (Kcv) and Ectocarpus siliculosus virus (Kesv). These small viral proteins readily assemble into tetramers and they sort in cells to distinct target membranes. When these viruses-encoded channels are expressed into the mammalian cells, they utilise their protein machinery and hence can serve as excellent tools to study the cells protein sorting machinery. This combination of small size and robust function makes viral K+ channels a valuable model system for detection of basic structure-function correlations. It is believed that molecular and physiochemical analyses of these viroporins may serve as basis for the development of inhibitors or modulators to ion channel activity for targeting ion channel diseases - so called channelopathies. Therefore, it may provide a potential different scope for molecular pharmacology studies aiming at novel and innovative therapeutics associated with channel related diseases. This article reviews the structural and functional properties of Kcv and Kesv upon expression in mammalian cells and Xenopus oocytes. The mechanisms behind differential protein sorting in Kcv and Kesv are also thoroughly discussed.
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Affiliation(s)
- Purva Asrani
- Biomolecular Spectroscopy and RUBiospec|NMR, Faculty of Chemistry and Biochemistry, Ruhr University of Bochum, Bochum D-44780, Germany
| | - Guiscard Seebohm
- Institute for Genetics of Heart Diseases (IfGH), Department of Cardiovascular Medicine, University Hospital Münster, Münster D-48149, Germany
| | - Raphael Stoll
- Biomolecular Spectroscopy and RUBiospec|NMR, Faculty of Chemistry and Biochemistry, Ruhr University of Bochum, Bochum D-44780, Germany.
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4
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Weerawardhana A, Uddin MB, Choi JH, Pathinayake P, Shin SH, Chathuranga K, Park JH, Lee JS. Foot-and-mouth disease virus non-structural protein 2B downregulates the RLR signaling pathway via degradation of RIG-I and MDA5. Front Immunol 2022; 13:1020262. [PMID: 36248821 PMCID: PMC9556895 DOI: 10.3389/fimmu.2022.1020262] [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: 08/16/2022] [Accepted: 09/13/2022] [Indexed: 11/17/2022] Open
Abstract
Foot-and-mouth disease virus (FMDV) is a single-stranded, positive-sense RNA virus containing at least 13 proteins. Many of these proteins show immune modulation capabilities. As a non-structural protein of the FMDV, 2B is involved in the rearrangement of the host cell membranes and the disruption of the host secretory pathway as a viroporin. Previous studies have also shown that FMDV 2B plays a role in the modulation of host type-I interferon (IFN) responses through the inhibition of expression of RIG-I and MDA5, key cytosolic sensors of the type-I IFN signaling. However, the exact molecular mechanism is poorly understood. Here, we demonstrated that FMDV 2B modulates host IFN signal pathway by the degradation of RIG-I and MDA5. FMDV 2B targeted the RIG-I for ubiquitination and proteasomal degradation by recruiting E3 ubiquitin ligase ring finger protein 125 (RNF125) and also targeted MDA5 for apoptosis-induced caspase-3- and caspase-8-dependent degradation. Ultimately, FMDV 2B significantly inhibited RNA virus-induced IFN-β production. Importantly, we identified that the C-terminal amino acids 126-154 of FMDV 2B are essential for 2B-mediated degradation of the RIG-I and MDA5. Collectively, these results provide a clearer understanding of the specific molecular mechanisms used by FMDV 2B to inhibit the IFN responses and a rational approach to virus attenuation for future vaccine development.
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Affiliation(s)
- Asela Weerawardhana
- College of Veterinary Medicine, Chungnam National University, Daejeon, South Korea
| | - Md Bashir Uddin
- College of Veterinary Medicine, Chungnam National University, Daejeon, South Korea
- Department of Medicine, Sylhet Agricultural University, Sylhet, Bangladesh
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States
| | - Joo-Hyung Choi
- Foot and Mouth Disease Division, Animal Quarantine and Inspection Agency, Anyang, South Korea
- Wildlife Disease Response Team, National Institute of Wildlife Disease Control and Prevention (NIWDC), Gwangju, South Korea
| | - Prabuddha Pathinayake
- College of Veterinary Medicine, Chungnam National University, Daejeon, South Korea
- Immune Health Program, Hunter Medical Research Institute, University of Newcastle, Newcastle, NSW, Australia
| | - Sung Ho Shin
- Foot and Mouth Disease Division, Animal Quarantine and Inspection Agency, Anyang, South Korea
| | - Kiramage Chathuranga
- College of Veterinary Medicine, Chungnam National University, Daejeon, South Korea
| | - Jong-Hyeon Park
- Foot and Mouth Disease Division, Animal Quarantine and Inspection Agency, Anyang, South Korea
- *Correspondence: Jong-Hyeon Park, ; Jong-Soo Lee,
| | - Jong-Soo Lee
- College of Veterinary Medicine, Chungnam National University, Daejeon, South Korea
- *Correspondence: Jong-Hyeon Park, ; Jong-Soo Lee,
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Cheng ML, Wu CH, Chien KY, Lai CH, Li GJ, Liu YY, Lin G, Ho HY. Enteroviral 2B Interacts with VDAC3 to Regulate Reactive Oxygen Species Generation That Is Essential to Viral Replication. Viruses 2022; 14:v14081717. [PMID: 36016340 PMCID: PMC9416218 DOI: 10.3390/v14081717] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 07/28/2022] [Accepted: 08/02/2022] [Indexed: 02/01/2023] Open
Abstract
Enterovirus (EV) 71 caused episodes of outbreaks in China and Southeast Asia during the last few decades. We have previously reported that EV71 induces reactive oxygen species (ROS). However, the underlying mechanism remains elusive. Co-immunoprecipitation-proteomic analysis revealed that enteroviral 2B protein interacted with mitochondrial voltage-dependent anion channel 3 (VDAC3). Knockdown (KD) of VDAC3 expression specifically inhibited enteroviral replication. Single-round viral replication was also inhibited in KD cells, suggesting that VDAC3 plays an essential role in replication. Consistent with this, VDAC3 gene KD significantly reduced the EV71-induced mitochondrial ROS generation. Exogenous 2B expression could induce the mitochondrial ROS generation that was significantly reduced in VDAC3-KD cells or in the Mito-TEMPO-treated cells. Moreover, VDAC3 appears to be necessary for regulation of antioxidant metabolism. VDAC3 gene KD led to the enhancement of such pathways as hypotaurine/taurine synthesis in the infected cells. Taken together, these findings suggest that 2B and VDAC3 interact to enhance mitochondrial ROS generation, which promotes viral replication.
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Affiliation(s)
- Mei-Ling Cheng
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan City 33302, Taiwan
- Healthy Aging Research Center, Chang Gung University, Taoyuan City 33302, Taiwan
- Metabolomics Core Laboratory, Healthy Aging Research Center, Chang Gung University, Taoyuan City 33302, Taiwan
- Clinical Metabolomics Core Laboratory, Chang Gung Memorial Hospital at Linkou, Taoyuan City 33302, Taiwan
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan City 33302, Taiwan
| | - Chien-Hsiang Wu
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan City 33302, Taiwan
| | - Kun-Yi Chien
- Department of Biochemistry and Molecular Biology, College of Medicine, Chang Gung University, Taoyuan City 33302, Taiwan
| | - Chien-Hsueh Lai
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan City 33302, Taiwan
| | - Guan-Jie Li
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan City 33302, Taiwan
| | - Yuan-Yu Liu
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan City 33302, Taiwan
| | - Gigin Lin
- Clinical Metabolomics Core Laboratory, Chang Gung Memorial Hospital at Linkou, Taoyuan City 33302, Taiwan
- Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital at Linkou, Taoyuan City 33302, Taiwan
- Imaging Core Laboratory, Institute for Radiological Research, Chang Gung University, Taoyuan City 33302, Taiwan
- Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taoyuan City 33302, Taiwan
| | - Hung-Yao Ho
- Healthy Aging Research Center, Chang Gung University, Taoyuan City 33302, Taiwan
- Metabolomics Core Laboratory, Healthy Aging Research Center, Chang Gung University, Taoyuan City 33302, Taiwan
- Clinical Metabolomics Core Laboratory, Chang Gung Memorial Hospital at Linkou, Taoyuan City 33302, Taiwan
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan City 33302, Taiwan
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan City 33302, Taiwan
- Research Center for Emerging Viral Infections, Chang Gung University, Taoyuan City 33302, Taiwan
- Correspondence: ; Tel.: +886-3-211-8800 (ext. 3318)
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Kakkanas A, Karamichali E, Koufogeorgou EI, Kotsakis SD, Georgopoulou U, Foka P. Targeting the YXXΦ Motifs of the SARS Coronaviruses 1 and 2 ORF3a Peptides by In Silico Analysis to Predict Novel Virus-Host Interactions. Biomolecules 2022; 12:1052. [PMID: 36008946 PMCID: PMC9405953 DOI: 10.3390/biom12081052] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 07/21/2022] [Accepted: 07/25/2022] [Indexed: 02/08/2023] Open
Abstract
The emerging SARS-CoV and SARS-CoV-2 belong to the family of "common cold" RNA coronaviruses, and they are responsible for the 2003 epidemic and the current pandemic with over 6.3 M deaths worldwide. The ORF3a gene is conserved in both viruses and codes for the accessory protein ORF3a, with unclear functions, possibly related to viral virulence and pathogenesis. The tyrosine-based YXXΦ motif (Φ: bulky hydrophobic residue-L/I/M/V/F) was originally discovered to mediate clathrin-dependent endocytosis of membrane-spanning proteins. Many viruses employ the YXXΦ motif to achieve efficient receptor-guided internalisation in host cells, maintain the structural integrity of their capsids and enhance viral replication. Importantly, this motif has been recently identified on the ORF3a proteins of SARS-CoV and SARS-CoV-2. Given that the ORF3a aa sequence is not fully conserved between the two SARS viruses, we aimed to map in silico structural differences and putative sequence-driven alterations of regulatory elements within and adjacently to the YXXΦ motifs that could predict variations in ORF3a functions. Using robust bioinformatics tools, we investigated the presence of relevant post-translational modifications and the YXXΦ motif involvement in protein-protein interactions. Our study suggests that the predicted YXXΦ-related features may confer specific-yet to be discovered-functions to ORF3a proteins, significant to the new virus and related to enhanced propagation, host immune regulation and virulence.
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Affiliation(s)
- Athanassios Kakkanas
- Laboratory of Molecular Virology, Hellenic Pasteur Institute, 115-21 Athens, Greece; (A.K.); (E.K.); (E.I.K.); (U.G.)
| | - Eirini Karamichali
- Laboratory of Molecular Virology, Hellenic Pasteur Institute, 115-21 Athens, Greece; (A.K.); (E.K.); (E.I.K.); (U.G.)
| | - Efthymia Ioanna Koufogeorgou
- Laboratory of Molecular Virology, Hellenic Pasteur Institute, 115-21 Athens, Greece; (A.K.); (E.K.); (E.I.K.); (U.G.)
| | - Stathis D. Kotsakis
- Laboratory of Bacteriology, Hellenic Pasteur Institute, 115-21 Athens, Greece;
| | - Urania Georgopoulou
- Laboratory of Molecular Virology, Hellenic Pasteur Institute, 115-21 Athens, Greece; (A.K.); (E.K.); (E.I.K.); (U.G.)
| | - Pelagia Foka
- Laboratory of Molecular Virology, Hellenic Pasteur Institute, 115-21 Athens, Greece; (A.K.); (E.K.); (E.I.K.); (U.G.)
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7
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Yan N, Wang Y, Chen Z, Liu A, Li Y, Yang B, Li K, Qi X, Gao Y, Gao L, Liu C, Zhang Y, Cui H, Pan Q, Wang X. Stromal Interaction Molecule 1 Promotes the Replication of vvIBDV by Mobilizing Ca2+ in the ER. Viruses 2022; 14:v14071524. [PMID: 35891504 PMCID: PMC9320076 DOI: 10.3390/v14071524] [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: 04/27/2022] [Revised: 06/20/2022] [Accepted: 06/27/2022] [Indexed: 12/10/2022] Open
Abstract
Infectious bursal disease virus (IBDV) is one of the main threats to the poultry industry worldwide. Very virulent IBDV (vvIBDV) is a fatal virus strain that causes heavy mortality in young chicken flocks. Ca2+ is one of the most universal and versatile signalling molecules and is involved in almost every aspect of cellular processes. Clinical examination showed that one of the characteristics of vvIBDV-infected chickens was severe metabolic disorders, and the chemical examination showed that their serum Ca2+ level decreased significantly. However, there are limited studies on how vvIBDV infection modulates the cellular Ca2+ level and the effect of Ca2+ level changes on vvIBDV replication. In our study, we found Ca2+ levels in the endoplasmic reticulum (ER) of vvIBDV-infected B cells were higher than that of mock-infected cells, and the expression level of stromal interaction molecule 1 (STIM1), an ER Ca2+ sensor, was significantly upregulated due to vvIBDV infection. The knock-down expression of STIM1 led to decreased Ca2+ level in the ER and suppressed vvIBDV replication, while the over-expressed STIM1 led to ER Ca2+ upregulation and promoted vvIBDV replication. We also showed that the inhibition of Ca2+-release-activated-Ca2+ (CRAC) channels could reduce vvIBDV infection by blocking Ca2+ from entering the ER. This study suggests a new mechanism that STIM1 promotes the replication of vvIBDV by mobilizing Ca2+ in the ER.
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Affiliation(s)
- Nana Yan
- State Key Laboratory of Veterinary Biotechnology, Avian Immunosuppressive Diseases Division, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China; (N.Y.); (Z.C.); (A.L.); (Y.L.); (B.Y.); (K.L.); (X.Q.); (Y.G.); (L.G.); (C.L.); (Y.Z.); (H.C.); (Q.P.)
| | - Yongqiang Wang
- State Key Laboratory of Veterinary Biotechnology, Avian Immunosuppressive Diseases Division, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China; (N.Y.); (Z.C.); (A.L.); (Y.L.); (B.Y.); (K.L.); (X.Q.); (Y.G.); (L.G.); (C.L.); (Y.Z.); (H.C.); (Q.P.)
- Correspondence: (Y.W.); (X.W.); Fax: +86-451-5199-7166 (X.W.)
| | - Zehua Chen
- State Key Laboratory of Veterinary Biotechnology, Avian Immunosuppressive Diseases Division, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China; (N.Y.); (Z.C.); (A.L.); (Y.L.); (B.Y.); (K.L.); (X.Q.); (Y.G.); (L.G.); (C.L.); (Y.Z.); (H.C.); (Q.P.)
| | - Aijing Liu
- State Key Laboratory of Veterinary Biotechnology, Avian Immunosuppressive Diseases Division, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China; (N.Y.); (Z.C.); (A.L.); (Y.L.); (B.Y.); (K.L.); (X.Q.); (Y.G.); (L.G.); (C.L.); (Y.Z.); (H.C.); (Q.P.)
| | - Yue Li
- State Key Laboratory of Veterinary Biotechnology, Avian Immunosuppressive Diseases Division, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China; (N.Y.); (Z.C.); (A.L.); (Y.L.); (B.Y.); (K.L.); (X.Q.); (Y.G.); (L.G.); (C.L.); (Y.Z.); (H.C.); (Q.P.)
| | - Bo Yang
- State Key Laboratory of Veterinary Biotechnology, Avian Immunosuppressive Diseases Division, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China; (N.Y.); (Z.C.); (A.L.); (Y.L.); (B.Y.); (K.L.); (X.Q.); (Y.G.); (L.G.); (C.L.); (Y.Z.); (H.C.); (Q.P.)
| | - Kai Li
- State Key Laboratory of Veterinary Biotechnology, Avian Immunosuppressive Diseases Division, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China; (N.Y.); (Z.C.); (A.L.); (Y.L.); (B.Y.); (K.L.); (X.Q.); (Y.G.); (L.G.); (C.L.); (Y.Z.); (H.C.); (Q.P.)
| | - Xiaole Qi
- State Key Laboratory of Veterinary Biotechnology, Avian Immunosuppressive Diseases Division, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China; (N.Y.); (Z.C.); (A.L.); (Y.L.); (B.Y.); (K.L.); (X.Q.); (Y.G.); (L.G.); (C.L.); (Y.Z.); (H.C.); (Q.P.)
| | - Yulong Gao
- State Key Laboratory of Veterinary Biotechnology, Avian Immunosuppressive Diseases Division, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China; (N.Y.); (Z.C.); (A.L.); (Y.L.); (B.Y.); (K.L.); (X.Q.); (Y.G.); (L.G.); (C.L.); (Y.Z.); (H.C.); (Q.P.)
| | - Li Gao
- State Key Laboratory of Veterinary Biotechnology, Avian Immunosuppressive Diseases Division, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China; (N.Y.); (Z.C.); (A.L.); (Y.L.); (B.Y.); (K.L.); (X.Q.); (Y.G.); (L.G.); (C.L.); (Y.Z.); (H.C.); (Q.P.)
| | - Changjun Liu
- State Key Laboratory of Veterinary Biotechnology, Avian Immunosuppressive Diseases Division, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China; (N.Y.); (Z.C.); (A.L.); (Y.L.); (B.Y.); (K.L.); (X.Q.); (Y.G.); (L.G.); (C.L.); (Y.Z.); (H.C.); (Q.P.)
| | - Yanping Zhang
- State Key Laboratory of Veterinary Biotechnology, Avian Immunosuppressive Diseases Division, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China; (N.Y.); (Z.C.); (A.L.); (Y.L.); (B.Y.); (K.L.); (X.Q.); (Y.G.); (L.G.); (C.L.); (Y.Z.); (H.C.); (Q.P.)
| | - Hongyu Cui
- State Key Laboratory of Veterinary Biotechnology, Avian Immunosuppressive Diseases Division, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China; (N.Y.); (Z.C.); (A.L.); (Y.L.); (B.Y.); (K.L.); (X.Q.); (Y.G.); (L.G.); (C.L.); (Y.Z.); (H.C.); (Q.P.)
| | - Qing Pan
- State Key Laboratory of Veterinary Biotechnology, Avian Immunosuppressive Diseases Division, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China; (N.Y.); (Z.C.); (A.L.); (Y.L.); (B.Y.); (K.L.); (X.Q.); (Y.G.); (L.G.); (C.L.); (Y.Z.); (H.C.); (Q.P.)
| | - Xiaomei Wang
- State Key Laboratory of Veterinary Biotechnology, Avian Immunosuppressive Diseases Division, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China; (N.Y.); (Z.C.); (A.L.); (Y.L.); (B.Y.); (K.L.); (X.Q.); (Y.G.); (L.G.); (C.L.); (Y.Z.); (H.C.); (Q.P.)
- Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonose, Yangzhou University, Yangzhou 225009, China
- Correspondence: (Y.W.); (X.W.); Fax: +86-451-5199-7166 (X.W.)
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8
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Xia X, Cheng A, Wang M, Ou X, Sun D, Mao S, Huang J, Yang Q, Wu Y, Chen S, Zhang S, Zhu D, Jia R, Liu M, Zhao XX, Gao Q, Tian B. Functions of Viroporins in the Viral Life Cycle and Their Regulation of Host Cell Responses. Front Immunol 2022; 13:890549. [PMID: 35720341 PMCID: PMC9202500 DOI: 10.3389/fimmu.2022.890549] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Accepted: 05/10/2022] [Indexed: 11/13/2022] Open
Abstract
Viroporins are virally encoded transmembrane proteins that are essential for viral pathogenicity and can participate in various stages of the viral life cycle, thereby promoting viral proliferation. Viroporins have multifaceted effects on host cell biological functions, including altering cell membrane permeability, triggering inflammasome formation, inducing apoptosis and autophagy, and evading immune responses, thereby ensuring that the virus completes its life cycle. Viroporins are also virulence factors, and their complete or partial deletion often reduces virion release and reduces viral pathogenicity, highlighting the important role of these proteins in the viral life cycle. Thus, viroporins represent a common drug-protein target for inhibiting drugs and the development of antiviral therapies. This article reviews current studies on the functions of viroporins in the viral life cycle and their regulation of host cell responses, with the aim of improving the understanding of this growing family of viral proteins.
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Affiliation(s)
- Xiaoyan Xia
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Anchun Cheng
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Mingshu Wang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Xumin Ou
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Di Sun
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Sai Mao
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Juan Huang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Qiao Yang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Ying Wu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Shun Chen
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Shaqiu Zhang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Dekang Zhu
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Renyong Jia
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Mafeng Liu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Xin-Xin Zhao
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Qun Gao
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
| | - Bin Tian
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu City, China
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9
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Sun M, Lin Q, Wang C, Xing J, Yan K, Liu Z, Jin Y, Cardona CJ, Xing Z. Enterovirus A71 2B Inhibits Interferon-Activated JAK/STAT Signaling by Inducing Caspase-3-Dependent Karyopherin-α1 Degradation. Front Microbiol 2022; 12:762869. [PMID: 34992585 PMCID: PMC8725996 DOI: 10.3389/fmicb.2021.762869] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 11/08/2021] [Indexed: 11/13/2022] Open
Abstract
Enterovirus A71 (EV-A71) is a major pathogen that causes the hand, foot, and mouth disease, which could be fatal with neurological complications in children. The underlying mechanism for the severe pathogenicity remains obscure, but impaired or aberrant innate immunity is considered to play a key role in viral pathogenesis. We reported previously that EV-A71 suppressed type I interferon (IFN) responses by inducing degradation of karyopherin-α1 (KPNA1), a component of the p-STAT1/2 complex. In this report, we showed that 2B, a non-structural protein of EV-A71, was critical to the suppression of the IFN-α-induced type I response in infected cells. Among viral proteins, 2B was the only one that was involved in the degradation of KPNA1, which impeded the formation of the p-STAT1/2/KPNA1 complex and blocked the translocation of p-STAT1/2 into the nucleus upon IFN-α stimulation. Degradation of KPNA1 induced by 2B can be inhibited in the cells pre-treated with Z-DEVD-FMK, a caspase-3 inhibitor, or siRNA targeting caspase-3, indicating that 2B-induced degradation of KPNA1 was caspase-3 dependent. The mechanism by which 2B functioned in the dysregulation of the IFN signaling was analyzed and a putative hydrophilic domain (H1) in the N-terminus of 2B was characterized to be critical for the release of cytochrome c into the cytosol for the activation of pro-caspase-3. We generated an EV-A71 infectious clone (rD1), which was deficient of the H1 domain. In rD1-infected cells, degradation of KPNA1 was relieved and the infected cells were more sensitive to IFN-α, leading to decreased viral replication, in comparison to the cells infected with the virus carrying a full length 2B. Our findings demonstrate that EV-A71 2B protein plays an important role in dysregulating JAK-STAT signaling through its involvement in promoting caspase-3 dependent degradation of KPNA1, which represents a novel strategy employed by EV-A71 to evade host antiviral innate immunity.
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Affiliation(s)
- Menghuai Sun
- Medical School and Jiangsu Provincial Key Laboratory of Medicine, Nanjing University, Nanjing, China.,Nanjing Children's Hospital, Nanjing Medical University, Nanjing, China.,Department of Gastroenterology, Beijing Children's Hospital, Capital Medical, University, National Center for Children's Health, China
| | - Qian Lin
- Nanjing Children's Hospital, Nanjing Medical University, Nanjing, China
| | - Chunyang Wang
- Clinical Medical College, Xi'an Medical University, Xi'an, China
| | - Jiao Xing
- Nanjing Children's Hospital, Nanjing Medical University, Nanjing, China
| | - Kunlong Yan
- Nanjing Children's Hospital, Nanjing Medical University, Nanjing, China
| | - Zhifeng Liu
- Nanjing Children's Hospital, Nanjing Medical University, Nanjing, China
| | - Yu Jin
- Medical School and Jiangsu Provincial Key Laboratory of Medicine, Nanjing University, Nanjing, China.,Nanjing Children's Hospital, Nanjing Medical University, Nanjing, China
| | - Carol J Cardona
- Department of Veterinary Biomedical Sciences, College of Veterinary Medicine, University of Minnesota at Twin Cities, Saint Paul, MN, United States
| | - Zheng Xing
- Department of Veterinary Biomedical Sciences, College of Veterinary Medicine, University of Minnesota at Twin Cities, Saint Paul, MN, United States
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10
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Gagliardi TB, Goldstein ME, Song D, Gray KM, Jung JW, Ignacio MA, Stroka KM, Duncan GA, Scull MA. Rhinovirus C replication is associated with the endoplasmic reticulum and triggers cytopathic effects in an in vitro model of human airway epithelium. PLoS Pathog 2022; 18:e1010159. [PMID: 34995322 PMCID: PMC8741012 DOI: 10.1371/journal.ppat.1010159] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 11/29/2021] [Indexed: 12/21/2022] Open
Abstract
The clinical impact of rhinovirus C (RV-C) is well-documented; yet, the viral life cycle remains poorly defined. Thus, we characterized RV-C15 replication at the single-cell level and its impact on the human airway epithelium (HAE) using a physiologically-relevant in vitro model. RV-C15 replication was restricted to ciliated cells where viral RNA levels peaked at 12 hours post-infection (hpi), correlating with elevated titers in the apical compartment at 24hpi. Notably, infection was associated with a loss of polarized expression of the RV-C receptor, cadherin-related family member 3. Visualization of double-stranded RNA (dsRNA) during RV-C15 replication revealed two distinct replication complex arrangements within the cell, likely corresponding to different time points in infection. To further define RV-C15 replication sites, we analyzed the expression and colocalization of giantin, phosphatidylinositol-4-phosphate, and calnexin with dsRNA. Despite observing Golgi fragmentation by immunofluorescence during RV-C15 infection as previously reported for other RVs, a high ratio of calnexin-dsRNA colocalization implicated the endoplasmic reticulum as the primary site for RV-C15 replication in HAE. RV-C15 infection was also associated with elevated stimulator of interferon genes (STING) expression and the induction of incomplete autophagy, a mechanism used by other RVs to facilitate non-lytic release of progeny virions. Notably, genetic depletion of STING in HAE attenuated RV-C15 and -A16 (but not -B14) replication, corroborating a previously proposed proviral role for STING in some RV infections. Finally, RV-C15 infection resulted in a temporary loss in epithelial barrier integrity and the translocation of tight junction proteins while a reduction in mucociliary clearance indicated cytopathic effects on epithelial function. Together, our findings identify both shared and unique features of RV-C replication compared to related rhinoviruses and define the impact of RV-C on both epithelial cell organization and tissue functionality–aspects of infection that may contribute to pathogenesis in vivo. Rhinovirus C has a global distribution and significant clinical impact–especially in those with underlying lung disease. Although RV-C is genetically, structurally, and biologically distinct from RV-A and -B viruses, our understanding of the RV-C life cycle has been largely inferred from these and other related viruses. Here, we performed a detailed analysis of RV-C15 replication in a physiologically-relevant model of human airway epithelium. Our single-cell, microscopy-based approach revealed that–unlike other RVs–the endoplasmic reticulum is the primary site for RV-C15 replication. RV-C15 replication also stimulated STING expression, which was proviral, and triggered dramatic changes in cellular organization, including altered virus receptor distribution, fragmented Golgi stacks, and the induction of incomplete autophagy. Additionally, we observed a loss of epithelial barrier function and a decrease in mucociliary clearance, a major defense mechanism in the lung, during RV-C15 infection. Together, these data reveal novel insight into RV-C15 replication dynamics and resulting cytopathic effects in the primary target cells for infection, thereby furthering our understanding of the pathogenesis of RV-C. Our work highlights similar, as well as unique, aspects of RV-C15 replication compared to related pathogens, which will help guide future studies on the molecular mechanisms of RV-C infection.
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Affiliation(s)
- Talita B. Gagliardi
- Department of Cell Biology and Molecular Genetics, Maryland Pathogen Research Institute, University of Maryland, College Park, Maryland, United States of America
| | - Monty E. Goldstein
- Department of Cell Biology and Molecular Genetics, Maryland Pathogen Research Institute, University of Maryland, College Park, Maryland, United States of America
| | - Daniel Song
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland, United States of America
| | - Kelsey M. Gray
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland, United States of America
| | - Jae W. Jung
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland, United States of America
| | - Maxinne A. Ignacio
- Department of Cell Biology and Molecular Genetics, Maryland Pathogen Research Institute, University of Maryland, College Park, Maryland, United States of America
| | - Kimberly M. Stroka
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland, United States of America
- Biophysics Program, University of Maryland, College Park, Maryland, United States of America
- Center for Stem Cell Biology and Regenerative Medicine, University of Maryland, Baltimore, Maryland, United States of America
- Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland, Baltimore, Maryland, United States of America
| | - Gregg A. Duncan
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland, United States of America
| | - Margaret A. Scull
- Department of Cell Biology and Molecular Genetics, Maryland Pathogen Research Institute, University of Maryland, College Park, Maryland, United States of America
- * E-mail:
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11
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Viruses in the Heart: Direct and Indirect Routes to Myocarditis and Heart Failure. Viruses 2021; 13:v13101924. [PMID: 34696354 PMCID: PMC8537553 DOI: 10.3390/v13101924] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 09/09/2021] [Accepted: 09/21/2021] [Indexed: 01/01/2023] Open
Abstract
Viruses are an underappreciated cause of heart failure. Indeed, several types of viral infections carry cardiovascular risks. Understanding shared and unique mechanisms by which each virus compromises heart function is critical to inform on therapeutic interventions. This review describes how the key viruses known to lead to cardiac dysfunction operate. Both direct host-damaging mechanisms and indirect actions on the immune systems are discussed. As viral myocarditis is a key pathologic driver of heart failure in infected individuals, this review also highlights the role of cytokine storms and inflammation in virus-induced cardiomyopathy.
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12
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Filipe IC, Guedes MS, Zdobnov EM, Tapparel C. Enterovirus D: A Small but Versatile Species. Microorganisms 2021; 9:1758. [PMID: 34442837 PMCID: PMC8400195 DOI: 10.3390/microorganisms9081758] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 08/09/2021] [Accepted: 08/10/2021] [Indexed: 12/13/2022] Open
Abstract
Enteroviruses (EVs) from the D species are the causative agents of a diverse range of infectious diseases in spite of comprising only five known members. This small clade has a diverse host range and tissue tropism. It contains types infecting non-human primates and/or humans, and for the latter, they preferentially infect the eye, respiratory tract, gastrointestinal tract, and nervous system. Although several Enterovirus D members, in particular EV-D68, have been associated with neurological complications, including acute myelitis, there is currently no effective treatment or vaccine against any of them. This review highlights the peculiarities of this viral species, focusing on genome organization, functional elements, receptor usage, and pathogenesis.
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Affiliation(s)
- Ines Cordeiro Filipe
- Department of Microbiology and Molecular Medicine, University of Geneva, 1206 Geneva, Switzerland;
| | - Mariana Soares Guedes
- Department of Microbiology and Molecular Medicine, University of Geneva, 1206 Geneva, Switzerland;
| | - Evgeny M. Zdobnov
- Department of Genetic Medicine and Development, Switzerland and Swiss Institute of Bioinformatics, University of Geneva, 1206 Geneva, Switzerland;
| | - Caroline Tapparel
- Department of Microbiology and Molecular Medicine, University of Geneva, 1206 Geneva, Switzerland;
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13
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IKKε isoform switching governs the immune response against EV71 infection. Commun Biol 2021; 4:663. [PMID: 34079066 PMCID: PMC8172566 DOI: 10.1038/s42003-021-02187-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Accepted: 04/30/2021] [Indexed: 12/19/2022] Open
Abstract
The reciprocal interactions between pathogens and hosts are complicated and profound. A comprehensive understanding of these interactions is essential for developing effective therapies against infectious diseases. Interferon responses induced upon virus infection are critical for establishing host antiviral innate immunity. Here, we provide a molecular mechanism wherein isoform switching of the host IKKε gene, an interferon-associated molecule, leads to alterations in IFN production during EV71 infection. We found that IKKε isoform 2 (IKKε v2) is upregulated while IKKε v1 is downregulated in EV71 infection. IKKε v2 interacts with IRF7 and promotes IRF7 activation through phosphorylation and translocation of IRF7 in the presence of ubiquitin, by which the expression of IFNβ and ISGs is elicited and virus propagation is attenuated. We also identified that IKKε v2 is activated via K63-linked ubiquitination. Our results suggest that host cells induce IKKε isoform switching and result in IFN production against EV71 infection. This finding highlights a gene regulatory mechanism in pathogen-host interactions and provides a potential strategy for establishing host first-line defense against pathogens.
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14
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Geisler A, Hazini A, Heimann L, Kurreck J, Fechner H. Coxsackievirus B3-Its Potential as an Oncolytic Virus. Viruses 2021; 13:v13050718. [PMID: 33919076 PMCID: PMC8143167 DOI: 10.3390/v13050718] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 04/16/2021] [Accepted: 04/19/2021] [Indexed: 02/06/2023] Open
Abstract
Oncolytic virotherapy represents one of the most advanced strategies to treat otherwise untreatable types of cancer. Despite encouraging developments in recent years, the limited fraction of patients responding to therapy has demonstrated the need to search for new suitable viruses. Coxsackievirus B3 (CVB3) is a promising novel candidate with particularly valuable features. Its entry receptor, the coxsackievirus and adenovirus receptor (CAR), and heparan sulfate, which is used for cellular entry by some CVB3 variants, are highly expressed on various cancer types. Consequently, CVB3 has broad anti-tumor activity, as shown in various xenograft and syngeneic mouse tumor models. In addition to direct tumor cell killing the virus induces a strong immune response against the tumor, which contributes to a substantial increase in the efficiency of the treatment. The toxicity of oncolytic CVB3 in healthy tissues is variable and depends on the virus strain. It can be abrogated by genetic engineering the virus with target sites of microRNAs. In this review, we present an overview of the current status of the development of CVB3 as an oncolytic virus and outline which steps still need to be accomplished to develop CVB3 as a therapeutic agent for clinical use in cancer treatment.
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Affiliation(s)
- Anja Geisler
- Department of Applied Biochemistry, Institute of Biotechnology, Technische Universität Berlin, 13355 Berlin, Germany; (A.G.); (L.H.); (J.K.)
| | - Ahmet Hazini
- Department of Oncology, University of Oxford, Oxford OX3 7DQ, UK;
| | - Lisanne Heimann
- Department of Applied Biochemistry, Institute of Biotechnology, Technische Universität Berlin, 13355 Berlin, Germany; (A.G.); (L.H.); (J.K.)
| | - Jens Kurreck
- Department of Applied Biochemistry, Institute of Biotechnology, Technische Universität Berlin, 13355 Berlin, Germany; (A.G.); (L.H.); (J.K.)
| | - Henry Fechner
- Department of Applied Biochemistry, Institute of Biotechnology, Technische Universität Berlin, 13355 Berlin, Germany; (A.G.); (L.H.); (J.K.)
- Correspondence: ; Tel.: +49-30-31-47-21-81
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15
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Panda S, Behera S, Alam MF, Syed GH. Endoplasmic reticulum & mitochondrial calcium homeostasis: The interplay with viruses. Mitochondrion 2021; 58:227-242. [PMID: 33775873 DOI: 10.1016/j.mito.2021.03.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Revised: 03/08/2021] [Accepted: 03/22/2021] [Indexed: 02/08/2023]
Abstract
Calcium ions (Ca2+) act as secondary messengers in a plethora of cellular processes and play crucial role in cellular organelle function and homeostasis. The average resting concentration of Ca2+ is nearly 100 nM and in certain cells it can reach up to 1 µM. The high range of Ca2+ concentration across the plasma membrane and intracellular Ca2+ stores demands a well-coordinated maintenance of free Ca2+ via influx, efflux, buffering and storage. Endoplasmic Reticulum (ER) and Mitochondria depend on Ca2+ for their function and also serve as major players in intracellular Ca2+ homeostasis. The ER-mitochondria interplay helps in orchestrating cellular calcium homeostasis to avoid any detrimental effect resulting from Ca2+ overload or depletion. Since Ca2+ plays a central role in many biological processes it is an essential component of the virus-host interactions. The large gradient across membranes enable the viruses to easily modulate this buffered environment to meet their needs. Viruses exploit Ca2+ signaling to establish productive infection and evade the host immune defense. In this review we will detail the interplay between the viruses and cellular & ER-mitochondrial calcium signaling and the significance of these events on viral life cycle and disease pathogenesis.
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Affiliation(s)
- Swagatika Panda
- Institute of Life Sciences, Bhubaneswar, Virus-Host Interaction Lab, Institute of Life Sciences, Bhubaneswar, India
| | - Suchismita Behera
- Institute of Life Sciences, Bhubaneswar, Clinical Proteomics Laboratory, Institute of Life Sciences, Bhubaneswar, India
| | - Mohd Faraz Alam
- Institute of Life Sciences, Bhubaneswar, Virus-Host Interaction Lab, Institute of Life Sciences, Bhubaneswar, India
| | - Gulam Hussain Syed
- Institute of Life Sciences, Bhubaneswar, Virus-Host Interaction Lab, Institute of Life Sciences, Bhubaneswar, India.
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16
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Owusu IA, Quaye O, Passalacqua KD, Wobus CE. Egress of non-enveloped enteric RNA viruses. J Gen Virol 2021; 102:001557. [PMID: 33560198 PMCID: PMC8515858 DOI: 10.1099/jgv.0.001557] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 01/04/2021] [Indexed: 12/27/2022] Open
Abstract
A long-standing paradigm in virology was that non-enveloped viruses induce cell lysis to release progeny virions. However, emerging evidence indicates that some non-enveloped viruses exit cells without inducing cell lysis, while others engage both lytic and non-lytic egress mechanisms. Enteric viruses are transmitted via the faecal-oral route and are important causes of a wide range of human infections, both gastrointestinal and extra-intestinal. Virus cellular egress, when fully understood, may be a relevant target for antiviral therapies, which could minimize the public health impact of these infections. In this review, we outline lytic and non-lytic cell egress mechanisms of non-enveloped enteric RNA viruses belonging to five families: Picornaviridae, Reoviridae, Caliciviridae, Astroviridae and Hepeviridae. We discuss factors that contribute to egress mechanisms and the relevance of these mechanisms to virion stability, infectivity and transmission. Since most data were obtained in traditional two-dimensional cell cultures, we will further attempt to place them into the context of polarized cultures and in vivo pathogenesis. Throughout the review, we highlight numerous knowledge gaps to stimulate future research into the egress mechanisms of these highly prevalent but largely understudied viruses.
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Affiliation(s)
- Irene A. Owusu
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109-5620, USA
- West African Centre for Cell Biology of Infectious Pathogens, Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana
| | - Osbourne Quaye
- West African Centre for Cell Biology of Infectious Pathogens, Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana
| | - Karla D. Passalacqua
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109-5620, USA
- Henry Ford Health System, Detroit, MI 48202, USA
| | - Christiane E. Wobus
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109-5620, USA
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17
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[Activation of positive-strand RNA virus genome replication complexes by host oxidation machinery and viroporins]. Uirusu 2021; 71:55-62. [PMID: 35526995 DOI: 10.2222/jsv.71.55] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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18
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Crespi B, Alcock J. Conflicts over calcium and the treatment of COVID-19. EVOLUTION MEDICINE AND PUBLIC HEALTH 2020; 9:149-156. [PMID: 33732462 PMCID: PMC7717197 DOI: 10.1093/emph/eoaa046] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 11/03/2020] [Indexed: 12/15/2022]
Abstract
Several recent studies have provided evidence that use of calcium channel blockers (CCBs), especially amlodipine and nifedipine, can reduce mortality from coronavirus disease 2019 (COVID-19). Moreover, hypocalcemia (a reduced level of serum ionized calcium) has been shown to be strongly positively associated with COVID-19 severity. Both effectiveness of CCBs as antiviral therapy, and positive associations of hypocalcemia with mortality, have been demonstrated for many other viruses as well. We evaluate these findings in the contexts of virus–host evolutionary conflicts over calcium metabolism, and hypocalcemia as either pathology, viral manipulation or host defence against pathogens. Considerable evidence supports the hypothesis that hypocalcemia represents a host defence. Indeed, hypocalcemia may exert antiviral effects in a similar manner as do CCBs, through interference with calcium metabolism in virus-infected cells. Prospective clinical studies that address the efficacy of CCBs and hypocalcemia should provide novel insights into the pathogenicity and treatment of COVID-19 and other viruses.
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Affiliation(s)
- Bernard Crespi
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Canada
| | - Joe Alcock
- Department of Emergency Medicine, University of New Mexico, Albuquerque, NM, USA
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19
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Zhang C, Xiong Y, Zeng L, Peng Z, Liu Z, Zhan H, Yang Z. The Role of Non-coding RNAs in Viral Myocarditis. Front Cell Infect Microbiol 2020; 10:312. [PMID: 32754448 PMCID: PMC7343704 DOI: 10.3389/fcimb.2020.00312] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Accepted: 05/22/2020] [Indexed: 12/13/2022] Open
Abstract
Viral myocarditis (VMC) is a disease characterized as myocardial parenchyma or interstitium inflammation caused by virus infection, especially Coxsackievirus B3 (CVB3) infection, which has no accurate non-invasive examination for diagnosis and specific drugs for treatment. The mechanism of CVB3-induced VMC may be related to direct myocardial damage of virus infection and extensive damage of abnormal immune response after infection. Non-coding RNA (ncRNA) refers to RNA that is not translated into protein and plays a vital role in many biological processes. There is expanding evidence to reveal that ncRNAs regulate the occurrence and development of VMC, which may provide new treatment or diagnosis targets. In this review, we mainly demonstrate an overview of the potential role of ncRNAs in the pathogenesis, diagnosis and treatment of CVB3-induced VMC.
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Affiliation(s)
- Cong Zhang
- Division of Emergency Medicine, Department of Emergency Intensive Care Unit, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- Department of Cardiology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- NHC Key Laboratory on Assisted Circulation (Sun Yat-sen University), Guangzhou, China
| | - Yan Xiong
- Division of Emergency Medicine, Department of Emergency Intensive Care Unit, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Lijin Zeng
- Division of Emergency Medicine, Department of Emergency Intensive Care Unit, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- Department of Cardiology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- NHC Key Laboratory on Assisted Circulation (Sun Yat-sen University), Guangzhou, China
| | - Zhihua Peng
- Division of Emergency Medicine, Department of Emergency Intensive Care Unit, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- Department of Cardiology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- NHC Key Laboratory on Assisted Circulation (Sun Yat-sen University), Guangzhou, China
| | - Zhihao Liu
- Division of Emergency Medicine, Department of Emergency Intensive Care Unit, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Hong Zhan
- Division of Emergency Medicine, Department of Emergency Intensive Care Unit, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Zhen Yang
- Division of Emergency Medicine, Department of Emergency Intensive Care Unit, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- Department of Cardiology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- NHC Key Laboratory on Assisted Circulation (Sun Yat-sen University), Guangzhou, China
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20
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Shrivastava G, Visoso-Carvajal G, Garcia-Cordero J, Leon-Juarez M, Chavez-Munguia B, Lopez T, Nava P, Villegas-Sepulveda N, Cedillo-Barron L. Dengue Virus Serotype 2 and Its Non-Structural Proteins 2A and 2B Activate NLRP3 Inflammasome. Front Immunol 2020; 11:352. [PMID: 32210961 PMCID: PMC7076137 DOI: 10.3389/fimmu.2020.00352] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 02/13/2020] [Indexed: 12/12/2022] Open
Abstract
Dengue is the most prevalent and rapidly transmitted mosquito-borne viral disease of humans. One of the fundamental innate immune responses to viral infections includes the processing and release of pro-inflammatory cytokines such as interleukin (IL-1β and IL-18) through the activation of inflammasome. Dengue virus stimulates the Nod-like receptor (NLRP3-specific inflammasome), however, the specific mechanism(s) by which dengue virus activates the NLRP3 inflammasome is unknown. In this study, we investigated the activation of the NLRP3 inflammasome in endothelial cells (HMEC-1) following dengue virus infection. Our results showed that dengue infection as well as the NS2A and NS2B protein expression increase the NLRP3 inflammasome activation, and further apoptosis-associated speck-like protein containing caspase recruitment domain (ASC) oligomerization, and IL-1β secretion through caspase-1 activation. Specifically, we have demonstrated that NS2A and NS2B, two proteins of dengue virus that behave as putative viroporins, were sufficient to stimulate the NLRP3 inflammasome complex in lipopolysaccharide (LPS)-primed endothelial cells. In summary, our observations provide insight into the dengue-induced inflammatory response mechanism and highlight the importance of DENV-2 NS2A and NS2B proteins in activation of the NLRP3 inflammasome during dengue virus infection.
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Affiliation(s)
- Gaurav Shrivastava
- Departmento de Biomedicina Molecular Centro de Investigación y Estudios Avanzados-Instituto Politécnico Nacional, Mexico City, Mexico
| | - Giovani Visoso-Carvajal
- Departmento de Biomedicina Molecular Centro de Investigación y Estudios Avanzados-Instituto Politécnico Nacional, Mexico City, Mexico
| | - Julio Garcia-Cordero
- Departmento de Biomedicina Molecular Centro de Investigación y Estudios Avanzados-Instituto Politécnico Nacional, Mexico City, Mexico
| | - Moisés Leon-Juarez
- Departamento de Inmunobioquímica, Instituto Nacional de Perinatología, Mexico City, Mexico
| | - Bibiana Chavez-Munguia
- Departamento de Infectomica y Biologia Molecular, Centro de Investigación y Estudios Avanzados-Instituto Politécnico Nacional, Mexico City, Mexico
| | - Tomas Lopez
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, UNAM Cuernavaca, Cuernavaca, Mexico
| | - Porfirio Nava
- Departamento de Fisiologia, Biofisica y Neurociencias, Cinvestav Zacatenco, Mexico City, Mexico
| | - Nicolás Villegas-Sepulveda
- Departmento de Biomedicina Molecular Centro de Investigación y Estudios Avanzados-Instituto Politécnico Nacional, Mexico City, Mexico
| | - Leticia Cedillo-Barron
- Departmento de Biomedicina Molecular Centro de Investigación y Estudios Avanzados-Instituto Politécnico Nacional, Mexico City, Mexico
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21
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Piganelli JD, Mamula MJ, James EA. The Role of β Cell Stress and Neo-Epitopes in the Immunopathology of Type 1 Diabetes. Front Endocrinol (Lausanne) 2020; 11:624590. [PMID: 33679609 PMCID: PMC7930070 DOI: 10.3389/fendo.2020.624590] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Accepted: 12/23/2020] [Indexed: 12/15/2022] Open
Abstract
Due to their secretory function, β cells are predisposed to higher levels of endoplasmic reticulum (ER) stress and greater sensitivity to inflammation than other cell types. These stresses elicit changes in β cells that alter their function and immunogenicity, including defective ribosomal initiation, post-translational modifications (PTMs) of endogenous β cell proteins, and alternative splicing. Multiple published reports confirm the presence of not only CD8+ T cells, but also autoreactive CD4+ T cells within pancreatic islets. Although the specificities of T cells that infiltrate human islets are incompletely characterized, they have been confirmed to include neo-epitopes that are formed through stress-related enzymatic modifications of β cell proteins. This article summarizes emerging knowledge about stress-induced changes in β cells and data supporting a role for neo-antigen formation and cross-talk between immune cells and β cells that provokes autoimmune attack - leading to a breakdown in tissue-specific tolerance in subjects who develop type 1 diabetes.
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Affiliation(s)
- Jon D. Piganelli
- Division of Pediatric Surgery, Department of Surgery, Children’s Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Mark J. Mamula
- Section of Rheumatology, Department of Medicine, Yale School of Medicine, New Haven, CT, United States
| | - Eddie A. James
- Translational Research Program, Benaroya Research Institute at Virginia Mason, Seattle, WA, United States
- *Correspondence: Eddie A. James,
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22
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Taverner WK, Jacobus EJ, Christianson J, Champion B, Paton AW, Paton JC, Su W, Cawood R, Seymour LW, Lei-Rossmann J. Calcium Influx Caused by ER Stress Inducers Enhances Oncolytic Adenovirus Enadenotucirev Replication and Killing through PKCα Activation. Mol Ther Oncolytics 2019; 15:117-130. [PMID: 31890865 PMCID: PMC6931121 DOI: 10.1016/j.omto.2019.09.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 09/22/2019] [Indexed: 01/17/2023] Open
Abstract
Oncolytic viruses represent an emerging approach to cancer therapy. However, better understanding of their interaction with the host cancer cell and approaches to enhance their efficacy are needed. Here, we investigate the effect of chemically induced endoplasmic reticulum (ER) stress on the activity of the chimeric group B adenovirus Enadenotucirev, its closely related parental virus Ad11p, and the archetypal group C oncolytic adenovirus Ad5. We show that treatment of colorectal and ovarian cancer cell lines with thapsigargin or ionomycin caused an influx of Ca2+, leading to an upregulation in E1A transcript and protein levels. Increased E1A protein levels, in turn, increased levels of expression of the E2B viral DNA polymerase, genome replication, late viral protein expression, infectious virus particle production, and cell killing during Enadenotucirev and Ad11p, but not Ad5, infection. This effect was not due to the induction of ER stress, but rather the influx of extracellular Ca2+ and consequent increase in protein kinase C activity. These results underscore the importance of Ca2+ homeostasis during adenoviral infection, indicate a signaling pathway between protein kinase C and E1A, and raise the possibility of using Ca2+ flux-modulating agents in the manufacture and potentiation of oncolytic virotherapies.
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Affiliation(s)
- William K. Taverner
- Department of Oncology, University of Oxford, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Egon J. Jacobus
- Department of Oncology, University of Oxford, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - John Christianson
- NDORMS, Botnar Research Centre, University of Oxford, Headington, Oxford OX3 7LD, UK
| | - Brian Champion
- PsiOxus Therapeutics, Ltd., Milton Park, Abingdon OX14 3YS, UK
| | - Adrienne W. Paton
- Research Centre for Infectious Diseases, Department of Molecular and Biomedical Science, University of Adelaide, Adelaide SA 5005, Australia
| | - James C. Paton
- Research Centre for Infectious Diseases, Department of Molecular and Biomedical Science, University of Adelaide, Adelaide SA 5005, Australia
| | - Weiheng Su
- Department of Oncology, University of Oxford, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Ryan Cawood
- Oxford Genetics Ltd., Medawar Centre, Robert Robinson Avenue, Oxford OX4 4HG, UK
| | - Len W. Seymour
- Department of Oncology, University of Oxford, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Janet Lei-Rossmann
- Department of Oncology, University of Oxford, Roosevelt Drive, Oxford OX3 7DQ, UK
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23
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Host Cell Calpains Can Cleave Structural Proteins from the Enterovirus Polyprotein. Viruses 2019; 11:v11121106. [PMID: 31795245 PMCID: PMC6950447 DOI: 10.3390/v11121106] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 11/26/2019] [Accepted: 11/26/2019] [Indexed: 12/25/2022] Open
Abstract
Enteroviruses are small RNA viruses that cause diseases with various symptoms ranging from mild to severe. Enterovirus proteins are translated as a single polyprotein, which is cleaved by viral proteases to release capsid and nonstructural proteins. Here, we show that also cellular calpains have a potential role in the processing of the enteroviral polyprotein. Using purified calpains 1 and 2 in an in vitro assay, we show that addition of calpains leads to an increase in the release of VP1 and VP3 capsid proteins from P1 of enterovirus B species, detected by western blotting. This was prevented with a calpain inhibitor and was dependent on optimal calcium concentration, especially for calpain 2. In addition, calpain cleavage at the VP3-VP1 interface was supported by a competition assay using a peptide containing the VP3-VP1 cleavage site. Moreover, a mass spectrometry analysis showed that calpains can cleave this same peptide at the VP3-VP1 interface, the cutting site being two amino acids aside from 3C’s cutting site. Furthermore, we show that calpains cannot cleave between P1 and 2A. In conclusion, we show that cellular proteases, calpains, can cleave structural proteins from enterovirus polyprotein in vitro. Whether they assist polyprotein processing in infected cells remains to be shown.
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24
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Lietzén N, Hirvonen K, Honkimaa A, Buchacher T, Laiho JE, Oikarinen S, Mazur MA, Flodström-Tullberg M, Dufour E, Sioofy-Khojine AB, Hyöty H, Lahesmaa R. Coxsackievirus B Persistence Modifies the Proteome and the Secretome of Pancreatic Ductal Cells. iScience 2019; 19:340-357. [PMID: 31404834 PMCID: PMC6699423 DOI: 10.1016/j.isci.2019.07.040] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 07/08/2019] [Accepted: 07/25/2019] [Indexed: 02/08/2023] Open
Abstract
The group B Coxsackieviruses (CVB), belonging to the Enterovirus genus, can establish persistent infections in human cells. These persistent infections have been linked to chronic diseases including type 1 diabetes. Still, the outcomes of persistent CVB infections in human pancreas are largely unknown. We established persistent CVB infections in a human pancreatic ductal-like cell line PANC-1 using two distinct CVB1 strains and profiled infection-induced changes in cellular protein expression and secretion using mass spectrometry-based proteomics. Persistent infections, showing characteristics of carrier-state persistence, were associated with a broad spectrum of changes, including changes in mitochondrial network morphology and energy metabolism and in the regulated secretory pathway. Interestingly, the expression of antiviral immune response proteins, and also several other proteins, differed clearly between the two persistent infections. Our results provide extensive information about the protein-level changes induced by persistent CVB infection and the potential virus-associated variability in the outcomes of these infections.
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Affiliation(s)
- Niina Lietzén
- Turku Bioscience Centre, University of Turku and Åbo Akademi University, FI-20520 Turku, Finland
| | - Karoliina Hirvonen
- Turku Bioscience Centre, University of Turku and Åbo Akademi University, FI-20520 Turku, Finland
| | - Anni Honkimaa
- Faculty of Medicine and Health Technology, Tampere University, FI-33014 Tampere, Finland
| | - Tanja Buchacher
- Turku Bioscience Centre, University of Turku and Åbo Akademi University, FI-20520 Turku, Finland
| | - Jutta E Laiho
- Faculty of Medicine and Health Technology, Tampere University, FI-33014 Tampere, Finland
| | - Sami Oikarinen
- Faculty of Medicine and Health Technology, Tampere University, FI-33014 Tampere, Finland
| | - Magdalena A Mazur
- Center for Infectious Medicine, Department of Medicine Huddinge, Karolinska Institutet, Karolinska University Hospital, Stockholm 141 86, Sweden
| | - Malin Flodström-Tullberg
- Center for Infectious Medicine, Department of Medicine Huddinge, Karolinska Institutet, Karolinska University Hospital, Stockholm 141 86, Sweden
| | - Eric Dufour
- Faculty of Medicine and Life Sciences, BioMediTech Institute and Tampere University Hospital, FI-33014 Tampere, Finland
| | | | - Heikki Hyöty
- Faculty of Medicine and Health Technology, Tampere University, FI-33014 Tampere, Finland; Fimlab Laboratories, Pirkanmaa Hospital District, FI-33520 Tampere, Finland
| | - Riitta Lahesmaa
- Turku Bioscience Centre, University of Turku and Åbo Akademi University, FI-20520 Turku, Finland.
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25
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Abstract
With no limiting membrane surrounding virions, nonenveloped viruses have no need for membrane fusion to gain access to intracellular replication compartments. Consequently, nonenveloped viruses do not encode membrane fusion proteins. The only exception to this dogma is the fusogenic reoviruses that encode fusion-associated small transmembrane (FAST) proteins that induce syncytium formation. FAST proteins are the smallest viral membrane fusion proteins and, unlike their enveloped virus counterparts, are nonstructural proteins that evolved specifically to induce cell-to-cell, not virus-cell, membrane fusion. This distinct evolutionary imperative is reflected in structural and functional features that distinguish this singular family of viral fusogens from all other protein fusogens. These rudimentary fusogens comprise specific combinations of different membrane effector motifs assembled into small, modular membrane fusogens. FAST proteins offer a minimalist model to better understand the ubiquitous process of protein-mediated membrane fusion and to reveal novel mechanisms of nonenveloped virus dissemination that contribute to virulence.
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Affiliation(s)
- Roy Duncan
- Department of Microbiology & Immunology, Department of Biochemistry & Molecular Biology, and Department of Pediatrics, Dalhousie University, Halifax, Nova Scotia, Canada, B3H 4R2;
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26
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Li Z, Zou Z, Jiang Z, Huang X, Liu Q. Biological Function and Application of Picornaviral 2B Protein: A New Target for Antiviral Drug Development. Viruses 2019; 11:v11060510. [PMID: 31167361 PMCID: PMC6630369 DOI: 10.3390/v11060510] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 05/31/2019] [Accepted: 06/02/2019] [Indexed: 12/22/2022] Open
Abstract
Picornaviruses are associated with acute and chronic diseases. The clinical manifestations of infections are often mild, but infections may also lead to respiratory symptoms, gastroenteritis, myocarditis, meningitis, hepatitis, and poliomyelitis, with serious impacts on human health and economic losses in animal husbandry. Thus far, research on picornaviruses has mainly focused on structural proteins such as VP1, whereas the non-structural protein 2B, which plays vital roles in the life cycle of the viruses and exhibits a viroporin or viroporin-like activity, has been overlooked. Viroporins are viral proteins containing at least one amphipathic α-helical structure, which oligomerizes to form transmembrane hydrophilic pores. In this review, we mainly summarize recent research data on the viroporin or viroporin-like activity of 2B proteins, which affects the biological function of the membrane, regulates cell death, and affects the host immune response. Considering these mechanisms, the potential application of the 2B protein as a candidate target for antiviral drug development is discussed, along with research challenges and prospects toward realizing a novel treatment strategy for picornavirus infections.
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Affiliation(s)
- Zengbin Li
- School of Public Health, Nanchang University, Nanchang 330006, China.
| | - Zixiao Zou
- Department of Medical Microbiology, School of Medicine, Nanchang University, Nanchang 330006, China.
| | - Zeju Jiang
- Jiangxi Medical College, Nanchang University, Nanchang 330006, China.
| | - Xiaotian Huang
- Department of Medical Microbiology, School of Medicine, Nanchang University, Nanchang 330006, China.
| | - Qiong Liu
- Department of Medical Microbiology, School of Medicine, Nanchang University, Nanchang 330006, China.
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27
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Abstract
BACKGROUND Coronaviruses (CoVs) primarily cause enzootic infections in birds and mammals but, in the last few decades, have shown to be capable of infecting humans as well. The outbreak of severe acute respiratory syndrome (SARS) in 2003 and, more recently, Middle-East respiratory syndrome (MERS) has demonstrated the lethality of CoVs when they cross the species barrier and infect humans. A renewed interest in coronaviral research has led to the discovery of several novel human CoVs and since then much progress has been made in understanding the CoV life cycle. The CoV envelope (E) protein is a small, integral membrane protein involved in several aspects of the virus' life cycle, such as assembly, budding, envelope formation, and pathogenesis. Recent studies have expanded on its structural motifs and topology, its functions as an ion-channelling viroporin, and its interactions with both other CoV proteins and host cell proteins. MAIN BODY This review aims to establish the current knowledge on CoV E by highlighting the recent progress that has been made and comparing it to previous knowledge. It also compares E to other viral proteins of a similar nature to speculate the relevance of these new findings. Good progress has been made but much still remains unknown and this review has identified some gaps in the current knowledge and made suggestions for consideration in future research. CONCLUSIONS The most progress has been made on SARS-CoV E, highlighting specific structural requirements for its functions in the CoV life cycle as well as mechanisms behind its pathogenesis. Data shows that E is involved in critical aspects of the viral life cycle and that CoVs lacking E make promising vaccine candidates. The high mortality rate of certain CoVs, along with their ease of transmission, underpins the need for more research into CoV molecular biology which can aid in the production of effective anti-coronaviral agents for both human CoVs and enzootic CoVs.
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Affiliation(s)
- Dewald Schoeman
- Molecular Biology and Virology Research Laboratory, Department of Medical Biosciences, University of the Western Cape, Cape Town, South Africa
| | - Burtram C Fielding
- Molecular Biology and Virology Research Laboratory, Department of Medical Biosciences, University of the Western Cape, Cape Town, South Africa.
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28
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Wang M, Li Z, Liu H, Wang X, Zhang D. Effect of fetal calf serum on propagation of duck hepatitis A virus genotype 3 in duck embryo fibroblast cells. BMC Vet Res 2019; 15:153. [PMID: 31101110 PMCID: PMC6525396 DOI: 10.1186/s12917-019-1904-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 05/09/2019] [Indexed: 11/26/2022] Open
Abstract
Background Duck viral hepatitis (DVH) is a highly contagious viral disease affecting ducks. It can be caused by five agents, including duck hepatitis A virus genotypes 1 (DHAV-1), 2 (DHAV-2), and 3 (DHAV-3), as well as duck hepatitis virus 2 and duck hepatitis virus 3. Since 2007, DHAV-3 has been known to be the most prevalent in East and South Asia. So far, the information regarding the propagation of DHAV-3 in cultured cells is limited. In this study, we describe the comparative studies on the growth properties of DHAV-3 in primary duck embryo fibroblast (DEF) cells using two different strains: a virulent strain C-GY and an attenuated strain YDF120. The effect of fetal calf serum (FCS) and chick serum (CS) on DHAV-3 replication and the mechanism of the inhibitory effect conferred by FCS were also investigated. Results Following serial passages, both C-GY and YDF120 failed to produce cytopathic effect and plaques. The combined quantitative real-time PCR and indirect immunofluorescence staining methods showed that the two viruses could be propagated productively in DEF cells. Investigation of the viral growth kinetics revealed that the two viruses replicated in DEF cells with similar efficiencies, while the viral load of the virulent C-GY strain peaked more rapidly when compared with the attenuated YDF120 strain. Neutralization assay and time-of-drug-addition study indicated that FCS displayed inhibitory effect on DHAV-3 replication. Analysis on the mechanism of action of FCS against DHAV-3 demonstrated that the inhibitory effect was reflected at three steps of the DHAV-3 life cycle including adsorption, replication, and release. Conclusions Both virulent and attenuated DAHV-3 strains can establish noncytocidal, productive infections in DEF cells. The virulent strain replicates more rapidly than the attenuated strain in early infection period. FCS has an inhibitory effect on DHAV-3 replication, which may be attributed to action of a non-specific inhibitory factor present in FCS directly on the virus. These findings may provide new insights into the development of potential antiviral agents.
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Affiliation(s)
- Minghang Wang
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, No. 2 Yuanmingyuan West Road, Haidian district, Beijing, 100193, People's Republic of China
| | - Ziheng Li
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, No. 2 Yuanmingyuan West Road, Haidian district, Beijing, 100193, People's Republic of China
| | - Huicong Liu
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, No. 2 Yuanmingyuan West Road, Haidian district, Beijing, 100193, People's Republic of China
| | - Xiaoyan Wang
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, No. 2 Yuanmingyuan West Road, Haidian district, Beijing, 100193, People's Republic of China
| | - Dabing Zhang
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, No. 2 Yuanmingyuan West Road, Haidian district, Beijing, 100193, People's Republic of China.
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29
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Foot-and-Mouth Disease Virus Antagonizes NOD2-Mediated Antiviral Effects by Inhibiting NOD2 Protein Expression. J Virol 2019; 93:JVI.00124-19. [PMID: 30894473 DOI: 10.1128/jvi.00124-19] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 03/15/2019] [Indexed: 12/30/2022] Open
Abstract
The role of nucleotide-binding oligomerization domain 2 (NOD2) in foot-and-mouth disease virus (FMDV)-infected cells remains unknown. Here, we showed that FMDV infection activated NOD2-mediated beta interferon (IFN-β) and nuclear factor-κB (NF-ĸB) signaling pathways. NOD2 inhibited FMDV replication in the infected cells. FMDV infection triggered NOD2 transcription, while it reduced the abundance of NOD2 protein. Our results revealed that FMDV 2B, 2C, and 3C proteinase (3Cpro) were responsible for the decrease in NOD2 protein levels. 3Cpro is a viral proteinase that can cleave multiple host proteins and limit protein synthesis. Our previous studies determined that FMDV 2B suppressed protein expression of RIG-I and LGP2. Here, we found that 3Cpro and 2B also decreased NOD2 expression. However, this is the first report that 2C induced the reduction of NOD2 protein levels. We determined that both 2B- and 2C-induced decreases in NOD2 were independent of the cleavage of host eukaryotic translation initiation factor 4 gamma (eIF4G), induction of cellular apoptosis, or proteasome, lysosome, and caspase pathways. The interactions between NOD2 and 2B or 2C were observed in the context of viral infection. The carboxyl-terminal amino acids 105 to 114 and 135 to 144 of 2B were essential for the reduction of NOD2, while the residues 105 to 114 were required for the interaction. Amino acids 116 to 260 of the carboxyl terminus of 2C were essential for the interaction, while truncated 2C mutants did not reduce NOD2. These data suggested novel antagonistic mechanisms of FMDV that were mediated by 2B, 2C, and 3Cpro proteins.IMPORTANCE NOD2 was identified as a cytoplasmic viral pattern recognition receptor in 2009. Subsequently, many viruses were reported to activate NOD2-mediated signaling pathways. This study demonstrated that FMDV infection activated NOD2-mediated IFN-β and NF-ĸB signaling pathways. Host cells have developed multiple strategies against viral infection; however, viruses have evolved many strategies to escape host defenses. FMDV has evolved multiple mechanisms to inhibit host type I IFN production. Here, we showed that NOD2 suppressed FMDV replication during viral infection. FMDV 2B, 2C, and 3Cpro decreased NOD2 protein expression by different mechanisms to promote viral replication. This study provided new insight into the immune evasion mechanisms mediated by FMDV and identified 2B, 2C, and 3Cpro as antagonistic factors for FMDV to evade host antiviral responses.
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30
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Yang Y, Cong H, Du N, Han X, Song L, Zhang W, Li C, Tien P. Mitochondria Redistribution in Enterovirus A71 Infected Cells and Its Effect on Virus Replication. Virol Sin 2019; 34:397-411. [PMID: 31069716 DOI: 10.1007/s12250-019-00120-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 03/25/2019] [Indexed: 10/26/2022] Open
Abstract
Enterovirus A71 (EV-A71) is one of the main causative agents of hand, foot and mouth disease (HFMD) and it also causes severe neurologic complications in infected children. The interactions between some viruses and the host mitochondria are crucial for virus replication and pathogenicity. In this study, it was observed that EV-A71 infection resulted in a perinuclear redistribution of the mitochondria. The mitochondria rearrangement was found to require the microtubule network, the dynein complex and a low cytosolic calcium concentration. Subsequently, the EV-A71 non-structural protein 2BC was identified as the viral protein capable of inducing mitochondria clustering. The protein was found localized on mitochondria and interacted with the mitochondrial Rho GTPase 1 (RHOT1) that is a key protein required for attachment between the mitochondria and the motor proteins, which are responsible for the control of mitochondria movement. Additionally, suppressing mitochondria clustering by treating cells with nocodazole, EHNA, thapsigargin or A23187 consistently inhibited EV-A71 replication, indicating that mitochondria recruitment played a crucial role in the EV-A71 life cycle. This study identified a novel function of the EV-A71 2BC protein and provided a potential model for the regulation of mitochondrial motility in EV-A71 infection.
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Affiliation(s)
- Yang Yang
- Center for Molecular Virology, CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.,University of the Chinese Academy of Sciences, Beijing, 100101, China
| | - Haolong Cong
- Center for Molecular Virology, CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Ning Du
- Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, 100101, China
| | - Xiaodong Han
- College of Life Sciences, Inner Mongolia Agriculture University, Hohhot, 010018, China
| | - Lei Song
- Center for Molecular Virology, CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Wenliang Zhang
- Center for Molecular Virology, CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Chunrui Li
- Center for Molecular Virology, CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.,University of the Chinese Academy of Sciences, Beijing, 100101, China
| | - Po Tien
- Center for Molecular Virology, CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China. .,University of the Chinese Academy of Sciences, Beijing, 100101, China.
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31
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The Saffold Virus-Penang 2B and 3C Proteins, but not the L Protein, Induce Apoptosis in HEp-2 and Vero Cells. Virol Sin 2019; 34:262-269. [PMID: 31016480 DOI: 10.1007/s12250-019-00116-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 02/22/2019] [Indexed: 10/27/2022] Open
Abstract
Our previous work has shown that Saffold virus (SAFV) induced several rodent and primate cell lines to undergo apoptosis (Xu et al. in Emerg Microb Infect 3:1-8, 2014), but the essential viral proteins of SAFV involved in apoptotic activity lack study. In this study, we individually transfected the viral proteins of SAFV into HEp-2 and Vero cells to assess their ability to induce apoptosis, and found that the 2B and 3C proteins are proapoptotic. Further investigation indicated the transmembrane domain of the 2B protein is essential for the apoptotic activity and tetramer formation of the 2B protein. Our research provides clues for the possible mechanisms of apoptosis induced by SAFV in different cell lines. It also opens up new directions to study viral proteins (the 2B, 3C protein), and sets the stage for future exploration of any possible link between SAFV, inclusive of its related uncultivable genotypes, and multiple sclerosis.
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Non-Structural Protein 2B of Human Rhinovirus 16 Activates Both PERK and ATF6 Rather Than IRE1 to Trigger ER Stress. Viruses 2019; 11:v11020133. [PMID: 30717233 PMCID: PMC6409610 DOI: 10.3390/v11020133] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 01/26/2019] [Accepted: 01/29/2019] [Indexed: 12/13/2022] Open
Abstract
To understand the underlying mechanisms of endoplasmic reticulum (ER) stress caused by human rhinovirus (HRV) 16 and non-structural transmembrane protein 2B, the expressions of ER chaperone glucose-regulated protein 78 (GRP78) and three signal transduction pathways, including protein kinase RNA-like ER kinase (PERK), activating transcription factor 6 (ATF6) and inositol-requiring enzyme 1 (IRE1), were evaluated after HRV16 infection and 2B gene transfection. Our results showed that both HRV16 infection and 2B gene transfection increased the expression of ER chaperone GRP78, and induced phosphorylation of PERK and cleavage of ATF6 in a time-dependent manner. Our data also revealed that the HRV16 2B protein was localized to the ER membrane. However, both HRV16 infection and HRV16 2B gene transfection did not induce ER stress through the IRE1 pathway. Moreover, our results showed that apoptosis occurred in H1-HeLa cells infected with HRV16 or transfected with 2B gene accompanied with increased expression of CHOP and cleaved caspase-3. Taken together, non-structural protein 2B of HRV16 induced an ER stress response through the PERK and ATF6 pathways rather than the IRE1 pathway.
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Nishikiori M, Ahlquist P. Organelle luminal dependence of (+)strand RNA virus replication reveals a hidden druggable target. SCIENCE ADVANCES 2018; 4:eaap8258. [PMID: 29387794 PMCID: PMC5787378 DOI: 10.1126/sciadv.aap8258] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 12/19/2017] [Indexed: 05/08/2023]
Abstract
Positive-strand RNA viruses replicate their genomes in membrane-bounded cytoplasmic complexes. We show that endoplasmic reticulum (ER)-linked genomic RNA replication by brome mosaic virus (BMV), a well-studied member of the alphavirus superfamily, depends on the ER luminal thiol oxidase ERO1. We further show that BMV RNA replication protein 1a, a key protein for the formation and function of vesicular BMV RNA replication compartments on ER membranes, permeabilizes these membranes to release oxidizing potential from the ER lumen. Conserved amphipathic sequences in 1a are sufficient to permeabilize liposomes, and mutations in these sequences simultaneously block membrane permeabilization, formation of a disulfide-linked, oxidized 1a multimer, 1a's RNA capping function, and productive genome replication. These results reveal new transmembrane complexities in positive-strand RNA virus replication, show that-as previously reported for certain picornaviruses and flaviviruses-some alphavirus superfamily members encode viroporins, identify roles for such viroporins in genome replication, and provide a potential new foundation for broad-spectrum antivirals.
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Affiliation(s)
- Masaki Nishikiori
- Institute for Molecular Virology, University of Wisconsin-Madison, Madison, WI 53706, USA
- McArdle Laboratory for Cancer Research, University of Wisconsin-Madison, Madison, WI 53706, USA
- Morgridge Institute for Research, Madison, WI 53715, USA
| | - Paul Ahlquist
- Institute for Molecular Virology, University of Wisconsin-Madison, Madison, WI 53706, USA
- McArdle Laboratory for Cancer Research, University of Wisconsin-Madison, Madison, WI 53706, USA
- Morgridge Institute for Research, Madison, WI 53715, USA
- Howard Hughes Medical Institute, University of Wisconsin-Madison, Madison, WI 53706, USA
- Corresponding author.
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Somiya M, Liu Q, Kuroda S. Current Progress of Virus-mimicking Nanocarriers for Drug Delivery. Nanotheranostics 2017; 1:415-429. [PMID: 29188175 PMCID: PMC5704007 DOI: 10.7150/ntno.21723] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2017] [Accepted: 10/09/2017] [Indexed: 12/14/2022] Open
Abstract
Nanomedicines often involve the use of nanocarriers as a delivery system for drugs or genes for maximizing the therapeutic effect and/or minimizing the adverse effect. From drug administration to therapeutic activity, nanocarriers must evade the host's immune system, specifically and efficiently target and enter the cell, and release their payload into the cell cytoplasm by endosomal escape. These processes constitute the early infection stage of viruses. Viruses are a powerful natural nanomaterial for the efficient delivery of genetic information by sophisticated mechanisms. Over the past two decades, many virus-inspired nanocarriers have been generated to permit successful drug and gene delivery. In this review, we summarize the early infection machineries of viruses, of which the part has so far been utilized for delivery systems. Furthermore, we describe basics and applications of the bio-nanocapsule, which is a hepatitis B virus-mimicking nanoparticle harboring nearly all activities involved in the early infection machineries (i.e., stealth activity, targeting activity, cell entry activity, endosomal escaping activity).
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Affiliation(s)
| | | | - Shun'ichi Kuroda
- The Institute of Scientific and Industrial Research, Osaka University, Osaka 567-0047, Japan
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Marré ML, Piganelli JD. Environmental Factors Contribute to β Cell Endoplasmic Reticulum Stress and Neo-Antigen Formation in Type 1 Diabetes. Front Endocrinol (Lausanne) 2017; 8:262. [PMID: 29033899 PMCID: PMC5626851 DOI: 10.3389/fendo.2017.00262] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 09/20/2017] [Indexed: 12/16/2022] Open
Abstract
Type 1 diabetes (T1D) is an autoimmune disease in which immune-mediated targeting and destruction of insulin-producing pancreatic islet β cells leads to chronic hyperglycemia. There are many β cell proteins that are targeted by autoreactive T cells in their native state. However, recent studies have demonstrated that many β cell proteins are recognized as neo-antigens following posttranslational modification (PTM). Although modified neo-antigens are well-established targets of pathology in other autoimmune diseases, the effects of neo-antigens in T1D progression and the mechanisms by which they are generated are not well understood. We have demonstrated that PTM occurs during endoplasmic reticulum (ER) stress, a process to which β cells are uniquely susceptible due to the high rate of insulin production in response to dynamic glucose sensing. In the context of genetic susceptibility to autoimmunity, presentation of these modified neo-antigens may activate autoreactive T cells and cause pathology. However, inherent β cell ER stress and protein PTM do not cause T1D in every genetically susceptible individual, suggesting the contribution of additional factors. Indeed, many environmental factors, such as viral infection, chemicals, or inflammatory cytokines, are associated with T1D onset, but the mechanisms by which these factors lead to disease onset remain unknown. Since these environmental factors also cause ER stress, exposure to these factors may enhance production of neo-antigens, therefore boosting β cell recognition by autoreactive T cells and exacerbating T1D pathogenesis. Therefore, the combined effects of physiological ER stress and the stress that is induced by environmental factors may lead to breaks in peripheral tolerance, contribute to antigen spread, and hasten disease onset. This Hypothesis and Theory article summarizes what is currently known about ER stress and protein PTM in autoimmune diseases including T1D and proposes a role for environmental factors in breaking immune tolerance to β cell antigens through neo-antigen formation.
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Affiliation(s)
- Meghan L Marré
- Division of Pediatric Surgery, Department of Surgery, Children's Hospital of Pittsburgh, University of Pittsburgh, Pittsburgh, PA, United States
| | - Jon D Piganelli
- Division of Pediatric Surgery, Department of Surgery, Children's Hospital of Pittsburgh, University of Pittsburgh, Pittsburgh, PA, United States
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Zhu Z, Wang G, Yang F, Cao W, Mao R, Du X, Zhang X, Li C, Li D, Zhang K, Shu H, Liu X, Zheng H. Foot-and-Mouth Disease Virus Viroporin 2B Antagonizes RIG-I-Mediated Antiviral Effects by Inhibition of Its Protein Expression. J Virol 2016; 90:11106-11121. [PMID: 27707918 PMCID: PMC5126369 DOI: 10.1128/jvi.01310-16] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Accepted: 09/25/2016] [Indexed: 12/26/2022] Open
Abstract
The role of retinoic acid-inducible gene I (RIG-I) in foot-and-mouth disease virus (FMDV)-infected cells remains unknown. Here, we showed that RIG-I inhibits FMDV replication in host cells. FMDV infection increased the transcription of RIG-I, while it decreased RIG-I protein expression. A detailed analysis revealed that FMDV leader proteinase (Lpro), as well as 3C proteinase (3Cpro) and 2B protein, decreased RIG-I protein expression. Lpro and 3Cpro are viral proteinases that can cleave various host proteins and are responsible for several of the viral polyprotein cleavages. However, for the first time, we observed 2B-induced reduction of host protein. Further studies showed that 2B-mediated reduction of RIG-I is specific to FMDV, but not other picornaviruses, including encephalomyocarditis virus, enterovirus 71, and coxsackievirus A16. Moreover, we found the decreased protein level of RIG-I is independent of the cleavage of eukaryotic translation initiation factor 4 gamma, the induction of cellular apoptosis, or the association of proteasome, lysosome, and caspase pathways. A direct interaction was observed between RIG-I and 2B. The carboxyl-terminal amino acids 105 to 114 and amino acids 135 to 144 of 2B were essential for the reduction of RIG-I, while residues 105 to 114 were required for the interaction. These data suggest the antiviral role of RIG-I against FMDV and a novel antagonistic mechanism of FMDV that is mediated by 2B protein. IMPORTANCE This study demonstrated that RIG-I could suppress FMDV replication during virus infection. FMDV infection increased the transcriptional expression of RIG-I, while it decreased RIG-I protein expression. FMDV 2B protein interacted with RIG-I and induced reduction of RIG-I. 2B-induced reduction of RIG-I was independent of the induction of the cleavage of eukaryotic translation initiation factor 4 gamma or cellular apoptosis. In addition, proteasome, lysosome, and caspase pathways were not involved in this process. This study provides new insight into the immune evasion mediated by FMDV and identifies 2B as an antagonistic factor for FMDV to evade the antiviral response.
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Affiliation(s)
- Zixiang Zhu
- State Key Laboratory of Veterinary Etiological Biology, National Foot and Mouth Diseases Reference Laboratory, Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Guoqing Wang
- State Key Laboratory of Veterinary Etiological Biology, National Foot and Mouth Diseases Reference Laboratory, Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Fan Yang
- State Key Laboratory of Veterinary Etiological Biology, National Foot and Mouth Diseases Reference Laboratory, Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Weijun Cao
- State Key Laboratory of Veterinary Etiological Biology, National Foot and Mouth Diseases Reference Laboratory, Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Ruoqing Mao
- State Key Laboratory of Veterinary Etiological Biology, National Foot and Mouth Diseases Reference Laboratory, Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Xiaoli Du
- State Key Laboratory of Veterinary Etiological Biology, National Foot and Mouth Diseases Reference Laboratory, Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Xiangle Zhang
- State Key Laboratory of Veterinary Etiological Biology, National Foot and Mouth Diseases Reference Laboratory, Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Chuntian Li
- State Key Laboratory of Veterinary Etiological Biology, National Foot and Mouth Diseases Reference Laboratory, Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Dan Li
- State Key Laboratory of Veterinary Etiological Biology, National Foot and Mouth Diseases Reference Laboratory, Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Keshan Zhang
- State Key Laboratory of Veterinary Etiological Biology, National Foot and Mouth Diseases Reference Laboratory, Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Hongbing Shu
- Collaborative Innovation Center for Viral Immunology, Medical Research Institute, Wuhan University, Wuhan, China
| | - Xiangtao Liu
- State Key Laboratory of Veterinary Etiological Biology, National Foot and Mouth Diseases Reference Laboratory, Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Haixue Zheng
- State Key Laboratory of Veterinary Etiological Biology, National Foot and Mouth Diseases Reference Laboratory, Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
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Abstract
Eukaryotic cells have evolved a myriad of ion channels, transporters, and pumps to maintain and regulate transmembrane ion gradients. As intracellular parasites, viruses also have evolved ion channel proteins, called viroporins, which disrupt normal ionic homeostasis to promote viral replication and pathogenesis. The first viral ion channel (influenza M2 protein) was confirmed only 23 years ago, and since then studies on M2 and many other viroporins have shown they serve critical functions in virus entry, replication, morphogenesis, and immune evasion. As new candidate viroporins and viroporin-mediated functions are being discovered, we review the experimental criteria for viroporin identification and characterization to facilitate consistency within this field of research. Then we review recent studies on how the few Ca(2+)-conducting viroporins exploit host signaling pathways, including store-operated Ca(2+) entry, autophagy, and inflammasome activation. These viroporin-induced aberrant Ca(2+) signals cause pathophysiological changes resulting in diarrhea, vomiting, and proinflammatory diseases, making both the viroporin and host Ca(2+) signaling pathways potential therapeutic targets for antiviral drugs.
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Affiliation(s)
- Joseph M Hyser
- Alkek Center for Metagenomic and Microbiome Research.,Department of Molecular Virology and Microbiology, and
| | - Mary K Estes
- Department of Molecular Virology and Microbiology, and.,Department of Medicine, Baylor College of Medicine, Houston, Texas 77030-3411;
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Enterovirus 71 2B Induces Cell Apoptosis by Directly Inducing the Conformational Activation of the Proapoptotic Protein Bax. J Virol 2016; 90:9862-9877. [PMID: 27558414 DOI: 10.1128/jvi.01499-16] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 08/15/2016] [Indexed: 12/13/2022] Open
Abstract
To survive and replicate within a host, many viruses have evolved strategies that target crucial components within the apoptotic cascade, leading to either inhibition or induction of cell apoptosis. Enterovirus 71 (EV71) infections have been demonstrated to impact the mitochondrial apoptotic pathway and induce apoptosis in many cell lines. However, the detailed mechanism of EV71-induced apoptosis remains to be elucidated. In this study, we report that EV71 2B protein (2B) localized to the mitochondria and induced cell apoptosis by interacting directly with and activating the proapoptotic protein Bax. 2B recruited Bax to the mitochondria and induced Bax conformational activation. In addition, mitochondria isolated from 2B-expressing cells that were treated with a recombinant Bax showed increased Bax interaction and cytochrome c (Cyt c) release. Importantly, apoptosis in cells with either EV71 infection or 2B expression was dramatically reduced in Bax knockdown cells but not in Bak knockdown cells, suggesting that Bax played a pivotal role in EV71- or 2B-induced apoptosis. Further studies indicate that a hydrophobic region of 18 amino acids (aa) in the C-terminal region of 2B (aa 63 to 80) was responsible for the location of 2B in the mitochondria. A hydrophilic region of 14 aa in the N-terminal region of 2B was functional in Bax interaction and its subsequent activation. Moreover, overexpression of the antiapoptotic protein Bcl-XL abrogates 2B-induced release of Cyt c and caspase activation. Therefore, this study provides direct evidence that EV71 2B induces cell apoptosis and impacts the mitochondrial apoptotic pathway by directly modulating the redistribution and activation of proapoptotic protein Bax. IMPORTANCE EV71 infections are usually accompanied by severe neurological complications. It has also been postulated that the induction of cell apoptosis resulting from tissue damage is a possible process of EV71-related pathogenesis. In this study, we report that EV71 2B protein (2B) localized to the mitochondria and induced cell apoptosis by interacting directly with and activating the proapoptotic protein Bax. This study provides evidence that EV71 induces cell apoptosis by modulating Bax activation and reveals important clues regarding the mechanism of Cyt c release and mitochondrial permeabilization during EV71 infection.
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39
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Clark AL, Urano F. Endoplasmic reticulum stress in beta cells and autoimmune diabetes. Curr Opin Immunol 2016; 43:60-66. [PMID: 27718448 DOI: 10.1016/j.coi.2016.09.006] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 09/06/2016] [Accepted: 09/23/2016] [Indexed: 12/29/2022]
Abstract
Type 1 diabetes results from the autoimmune destruction of pancreatic β cells, leading to insulin deficiency and hyperglycemia. Although multiple attempts have been made to slow the autoimmune process using immunosuppressive or immunomodulatory agents, there are still no effective treatments that can delay or reverse the progression of type 1 diabetes in humans. Recent studies support endoplasmic reticulum (ER) as a novel target for preventing the initiation of the autoimmune reaction, propagation of inflammation, and β cell death in type 1 diabetes. This review highlights recent findings on ER stress in β cells and development of type 1 diabetes and introduces potential new treatments targeting the ER to combat this disorder.
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Affiliation(s)
- Amy L Clark
- Department of Pediatrics, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Fumihiko Urano
- Department of Medicine, Division of Endocrinology, Metabolism, and Lipid Research, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA.
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40
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Dey D, Banerjee M. Inhibitor-Based Therapeutics for Treatment of Viral Hepatitis. J Clin Transl Hepatol 2016; 4:248-257. [PMID: 27777893 PMCID: PMC5075008 DOI: 10.14218/jcth.2016.00025] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 09/14/2016] [Accepted: 09/14/2016] [Indexed: 12/12/2022] Open
Abstract
Viral hepatitis remains a significant worldwide threat, in spite of the availability of several successful therapeutic and vaccination strategies. Complications associated with acute and chronic infections, such as liver failure, cirrhosis and hepatocellular carcinoma, are the cause of considerable morbidity and mortality. Given the significant burden on the healthcare system caused by viral hepatitis, it is essential that novel, more effective therapeutics be developed. The present review attempts to summarize the current treatments against viral hepatitis, and provides an outline for upcoming, promising new therapeutics. Development of novel therapeutics requires an understanding of the viral life cycles and viral effectors in molecular detail. As such, this review also discusses virally-encoded effectors, found to be essential for virus survival and replication in the host milieu, which may be utilized as potential candidates for development of alternative therapies in the future.
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Affiliation(s)
- Debajit Dey
- Kusuma School of Biological Sciences, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, India
| | - Manidipa Banerjee
- Kusuma School of Biological Sciences, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, India
- *Correspondence to: Dr. Manidipa Banerjee, Kusuma School of Biological Sciences, Indian Institute of Technology Delhi, Block 1A, Hauz Khas, New Delhi 110016, India. Tel: +91-11-26597538, Fax: +91-11-26597530, E-mail:
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41
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Wu H, Zhai X, Chen Y, Wang R, Lin L, Chen S, Wang T, Zhong X, Wu X, Wang Y, Zhang F, Zhao W, Zhong Z. Protein 2B of Coxsackievirus B3 Induces Autophagy Relying on Its Transmembrane Hydrophobic Sequences. Viruses 2016; 8:v8050131. [PMID: 27187444 PMCID: PMC4885086 DOI: 10.3390/v8050131] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Revised: 04/18/2016] [Accepted: 04/26/2016] [Indexed: 01/20/2023] Open
Abstract
Coxsackievirus B (CVB) belongs to Enterovirus genus within the Picornaviridae family, and it is one of the most common causative pathogens of viral myocarditis in young adults. The pathogenesis of myocarditis caused by CVB has not been completely elucidated. In CVB infection, autophagy is manipulated to facilitate viral replication. Here we report that protein 2B, one of the non-structural proteins of CVB3, possesses autophagy-inducing capability. The autophagy-inducing motif of protein 2B was identified by the generation of truncated 2B and site-directed mutagenesis. The expression of 2B alone was sufficient to induce the formation of autophagosomes in HeLa cells, while truncated 2B containing the two hydrophobic regions of the protein also induced autophagy. In addition, we demonstrated that a single amino acid substitution (56V→A) in the stem loop in between the two hydrophobic regions of protein 2B abolished the formation of autophagosomes. Moreover, we found that 2B and truncated 2B with autophagy-inducting capability were co-localized with LC3-II. This study indicates that protein 2B relies on its transmembrane hydrophobic regions to induce the formation of autophagosomes, while 56 valine residue in the stem loop of protein 2B might exert critical structural influence on its two hydrophobic regions. These results may provide new insight for understanding the molecular mechanism of autophagy triggered by CVB infection.
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Affiliation(s)
- Heng Wu
- Department of Microbiology and Wu Lien-Teh Institute, Harbin Medical University, 157 Baojian Road, Harbin 150081, China.
- Department of Reproductive Medicine, The First Hospital of Harbin Medical University, 23 Youzheng Street, Harbin 150001, China.
| | - Xia Zhai
- Department of Microbiology and Wu Lien-Teh Institute, Harbin Medical University, 157 Baojian Road, Harbin 150081, China.
| | - Yang Chen
- Department of Microbiology and Wu Lien-Teh Institute, Harbin Medical University, 157 Baojian Road, Harbin 150081, China.
| | - Ruixue Wang
- Department of Microbiology and Wu Lien-Teh Institute, Harbin Medical University, 157 Baojian Road, Harbin 150081, China.
| | - Lexun Lin
- Department of Microbiology and Wu Lien-Teh Institute, Harbin Medical University, 157 Baojian Road, Harbin 150081, China.
| | - Sijia Chen
- Department of Microbiology and Wu Lien-Teh Institute, Harbin Medical University, 157 Baojian Road, Harbin 150081, China.
| | - Tianying Wang
- Department of Microbiology and Wu Lien-Teh Institute, Harbin Medical University, 157 Baojian Road, Harbin 150081, China.
| | - Xiaoyan Zhong
- Department of Microbiology and Wu Lien-Teh Institute, Harbin Medical University, 157 Baojian Road, Harbin 150081, China.
| | - Xiaoyu Wu
- Department of Cardiology, The First Hospital of Harbin Medical University, 23 Youzheng Street, Harbin 150001, China.
| | - Yan Wang
- Department of Microbiology and Wu Lien-Teh Institute, Harbin Medical University, 157 Baojian Road, Harbin 150081, China.
| | - Fengmin Zhang
- Department of Microbiology and Wu Lien-Teh Institute, Harbin Medical University, 157 Baojian Road, Harbin 150081, China.
| | - Wenran Zhao
- Department of Cell Biology, Harbin Medical University, 157 Baojian Road, Harbin 150081, China.
| | - Zhaohua Zhong
- Department of Microbiology and Wu Lien-Teh Institute, Harbin Medical University, 157 Baojian Road, Harbin 150081, China.
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42
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Marré ML, Profozich JL, Coneybeer JT, Geng X, Bertera S, Ford MJ, Trucco M, Piganelli JD. Inherent ER stress in pancreatic islet β cells causes self-recognition by autoreactive T cells in type 1 diabetes. J Autoimmun 2016; 72:33-46. [PMID: 27173406 DOI: 10.1016/j.jaut.2016.04.009] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Revised: 04/25/2016] [Accepted: 04/30/2016] [Indexed: 01/10/2023]
Abstract
Type 1 diabetes (T1D) is an autoimmune disease characterized by pancreatic β cell destruction induced by islet reactive T cells that have escaped central tolerance. Many physiological and environmental triggers associated with T1D result in β cell endoplasmic reticulum (ER) stress and dysfunction, increasing the potential for abnormal post-translational modification (PTM) of proteins. We hypothesized that β cell ER stress induced by environmental and physiological conditions generates abnormally-modified proteins for the T1D autoimmune response. To test this hypothesis we exposed the murine CD4(+) diabetogenic BDC2.5 T cell clone to murine islets in which ER stress had been induced chemically (Thapsigargin). The BDC2.5 T cell IFNγ response to these cells was significantly increased compared to non-treated islets. This β cell ER stress increased activity of the calcium (Ca(2+))-dependent PTM enzyme tissue transglutaminase 2 (Tgase2), which was necessary for full stress-dependent immunogenicity. Indeed, BDC2.5 T cells responded more strongly to their antigen after its modification by Tgase2. Finally, exposure of non-antigenic murine insulinomas to chemical ER stress in vitro or physiological ER stress in vivo caused increased ER stress and Tgase2 activity, culminating in higher BDC2.5 responses. Thus, β cell ER stress induced by chemical and physiological triggers leads to β cell immunogenicity through Ca(2+)-dependent PTM. These findings elucidate a mechanism of how β cell proteins are modified and become immunogenic, and reveal a novel opportunity for preventing β cell recognition by autoreactive T cells.
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MESH Headings
- Amino Acid Sequence
- Animals
- Autoantigens/genetics
- Autoantigens/immunology
- Autoimmunity/genetics
- Autoimmunity/immunology
- Blotting, Western
- CD4-Positive T-Lymphocytes/immunology
- CD4-Positive T-Lymphocytes/metabolism
- Calcium/immunology
- Calcium/metabolism
- Cell Line
- Cells, Cultured
- Chromogranin A/genetics
- Chromogranin A/immunology
- Chromogranin A/metabolism
- Diabetes Mellitus, Type 1/genetics
- Diabetes Mellitus, Type 1/immunology
- Diabetes Mellitus, Type 1/metabolism
- Endoplasmic Reticulum Stress/genetics
- Endoplasmic Reticulum Stress/immunology
- GTP-Binding Proteins/genetics
- GTP-Binding Proteins/immunology
- GTP-Binding Proteins/metabolism
- Humans
- Insulin-Secreting Cells/immunology
- Insulin-Secreting Cells/metabolism
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Inbred NOD
- Mice, SCID
- Models, Immunological
- Protein Glutamine gamma Glutamyltransferase 2
- Protein Processing, Post-Translational/immunology
- Reverse Transcriptase Polymerase Chain Reaction
- Tandem Mass Spectrometry
- Transglutaminases/genetics
- Transglutaminases/immunology
- Transglutaminases/metabolism
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Affiliation(s)
- Meghan L Marré
- Division of Immunogenetics, Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, 4401 Penn Avenue, Pittsburgh, PA 15224, USA
| | - Jennifer L Profozich
- Division of Immunogenetics, Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, 4401 Penn Avenue, Pittsburgh, PA 15224, USA
| | - Jorge T Coneybeer
- Division of Immunogenetics, Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, 4401 Penn Avenue, Pittsburgh, PA 15224, USA
| | - Xuehui Geng
- Division of Immunogenetics, Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, 4401 Penn Avenue, Pittsburgh, PA 15224, USA
| | - Suzanne Bertera
- Division of Immunogenetics, Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, 4401 Penn Avenue, Pittsburgh, PA 15224, USA
| | - Michael J Ford
- MS Bioworks, LLC, 3950 Varsity Drive, Ann Arbor, MI 48108, USA
| | - Massimo Trucco
- Division of Immunogenetics, Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, 4401 Penn Avenue, Pittsburgh, PA 15224, USA
| | - Jon D Piganelli
- Division of Immunogenetics, Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, 4401 Penn Avenue, Pittsburgh, PA 15224, USA.
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Khaw YS, Chan YF, Jafar FL, Othman N, Chee HY. Comparative Genetic Analyses of Human Rhinovirus C (HRV-C) Complete Genome from Malaysia. Front Microbiol 2016; 7:543. [PMID: 27199901 PMCID: PMC4851184 DOI: 10.3389/fmicb.2016.00543] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 04/04/2016] [Indexed: 11/17/2022] Open
Abstract
Human rhinovirus-C (HRV-C) has been implicated in more severe illnesses than HRV-A and HRV-B, however, the limited number of HRV-C complete genomes (complete 5′ and 3′ non-coding region and open reading frame sequences) has hindered the in-depth genetic study of this virus. This study aimed to sequence seven complete HRV-C genomes from Malaysia and compare their genetic characteristics with the 18 published HRV-Cs. Seven Malaysian HRV-C complete genomes were obtained with newly redesigned primers. The seven genomes were classified as HRV-C6, C12, C22, C23, C26, C42, and pat16 based on the VP4/VP2 and VP1 pairwise distance threshold classification. Five of the seven Malaysian isolates, namely, 3430-MY-10/C22, 8713-MY-10/C23, 8097-MY-11/C26, 1570-MY-10/C42, and 7383-MY-10/pat16 are the first newly sequenced complete HRV-C genomes. All seven Malaysian isolates genomes displayed nucleotide similarity of 63–81% among themselves and 63–96% with other HRV-Cs. Malaysian HRV-Cs had similar putative immunogenic sites, putative receptor utilization and potential antiviral sites as other HRV-Cs. The genomic features of Malaysian isolates were similar to those of other HRV-Cs. Negative selections were frequently detected in HRV-Cs complete coding sequences indicating that these sequences were under functional constraint. The present study showed that HRV-Cs from Malaysia have diverse genetic sequences but share conserved genomic features with other HRV-Cs. This genetic information could provide further aid in the understanding of HRV-C infection.
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Affiliation(s)
- Yam Sim Khaw
- Department of Medical Microbiology and Parasitology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia Serdang, Malaysia
| | - Yoke Fun Chan
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya Kuala Lumpur, Malaysia
| | - Faizatul Lela Jafar
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya Kuala Lumpur, Malaysia
| | - Norlijah Othman
- Department of Paediatrics, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia Serdang, Malaysia
| | - Hui Yee Chee
- Department of Medical Microbiology and Parasitology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia Serdang, Malaysia
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Enterovirus 71 induces dsRNA/PKR-dependent cytoplasmic redistribution of GRP78/BiP to promote viral replication. Emerg Microbes Infect 2016; 5:e23. [PMID: 27004760 PMCID: PMC4820672 DOI: 10.1038/emi.2016.20] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Revised: 11/19/2015] [Accepted: 11/23/2015] [Indexed: 12/16/2022]
Abstract
GRP78/BiP is an endoplasmic reticulum (ER) chaperone protein with the important function of maintaining ER homeostasis, and the overexpression of GRP78/BiP alleviates ER stress. Our previous studies showed that infection with enterovirus 71 (EV71), a (+)RNA picornavirus, induced GRP78/BiP upregulation; however, ectopic GRP78/BiP overexpression in ER downregulates virus replication and viral particle formation. The fact that a virus infection increases GRP78/BiP expression, which is unfavorable for virus replication, is counterintuitive. In this study, we found that the GRP78/BiP protein level was elevated in the cytoplasm instead of in the ER in EV71-infected cells. Cells transfected with polyinosinic-polycytidylic acid, a synthetic analog of replicative double-stranded RNA (dsRNA), but not with viral proteins, also exhibited upregulation and elevation of GRP78/BiP in the cytosol. Our results further demonstrate that EV71 infections induce the dsRNA/protein kinase R-dependent cytosolic accumulation of GRP78/BiP. The overexpression of a GRP78/BiP mutant lacking a KDEL retention signal failed to inhibit both dithiothreitol-induced eIF2α phosphorylation and viral replication in the context of viral protein synthesis and viral titers. These data revealed that EV71 infection might cause upregulation and aberrant redistribution of GRP78/BiP to the cytosol, thereby facilitating virus replication.
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Qiu Y, Ye X, Hanson PJ, Zhang HM, Zong J, Cho B, Yang D. Hsp70-1: upregulation via selective phosphorylation of heat shock factor 1 during coxsackieviral infection and promotion of viral replication via the AU-rich element. Cell Mol Life Sci 2016; 73:1067-84. [PMID: 26361762 PMCID: PMC11108310 DOI: 10.1007/s00018-015-2036-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 08/13/2015] [Accepted: 09/03/2015] [Indexed: 01/03/2023]
Abstract
Coxsackievirus B3 (CVB3) is the primary pathogen of viral myocarditis. Upon infection, CVB3 exploits the host cellular machineries, such as chaperone proteins, to benefit its own infection cycles. Inducible heat shock 70-kDa proteins (Hsp70s) are chaperone proteins induced by various cellular stress conditions. The internal ribosomal entry site (IRES) within Hsp70 mRNA allows Hsp70 to be translated cap-independently during CVB3 infection when global cap-dependent translation is compromised. The Hsp70 protein family contains two major members, Hsp70-1 and Hsp70-2. This study showed that Hsp70-1, but not Hsp70-2, was upregulated during CVB3 infection both in vitro and in vivo. Then a novel mechanism of Hsp70-1 induction was revealed in which CaMKIIγ is activated by CVB3 replication and leads to phosphorylation of heat shock factor 1 (HSF1) specifically at Serine 230, which enhances Hsp70-1 transcription. Meanwhile, phosphorylation of Ser230 induces translocation of HSF1 from the cytoplasm to nucleus, thus blocking the ERK1/2-mediated phosphorylation of HSF1 at Ser307, a negative regulatory process of Hsp70 transcription, further contributing to Hsp70-1 upregulation. Finally, we demonstrated that Hsp70-1 upregulation, in turn, stabilizes CVB3 genome via the AU-rich element (ARE) harbored in the 3' untranslated region of CVB3 genomic RNA.
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Affiliation(s)
- Ye Qiu
- Department of Pathology and Laboratory Medicine, University of British Columbia, 2211 Wesbrook Mall, Vancouver, BC, V6T 2B5, Canada
- Centre for Heart Lung Innovation, University of British Columbia and St. Paul's Hospital, 1081 Burrard Street, Vancouver, BC, V6Z 1Y6, Canada
| | - Xin Ye
- Department of Pathology and Laboratory Medicine, University of British Columbia, 2211 Wesbrook Mall, Vancouver, BC, V6T 2B5, Canada
- Centre for Heart Lung Innovation, University of British Columbia and St. Paul's Hospital, 1081 Burrard Street, Vancouver, BC, V6Z 1Y6, Canada
| | - Paul J Hanson
- Department of Pathology and Laboratory Medicine, University of British Columbia, 2211 Wesbrook Mall, Vancouver, BC, V6T 2B5, Canada
- Centre for Heart Lung Innovation, University of British Columbia and St. Paul's Hospital, 1081 Burrard Street, Vancouver, BC, V6Z 1Y6, Canada
| | - Huifang Mary Zhang
- Department of Pathology and Laboratory Medicine, University of British Columbia, 2211 Wesbrook Mall, Vancouver, BC, V6T 2B5, Canada
- Centre for Heart Lung Innovation, University of British Columbia and St. Paul's Hospital, 1081 Burrard Street, Vancouver, BC, V6Z 1Y6, Canada
| | - Jeff Zong
- Centre for Heart Lung Innovation, University of British Columbia and St. Paul's Hospital, 1081 Burrard Street, Vancouver, BC, V6Z 1Y6, Canada
| | - Brian Cho
- Centre for Heart Lung Innovation, University of British Columbia and St. Paul's Hospital, 1081 Burrard Street, Vancouver, BC, V6Z 1Y6, Canada
| | - Decheng Yang
- Department of Pathology and Laboratory Medicine, University of British Columbia, 2211 Wesbrook Mall, Vancouver, BC, V6T 2B5, Canada.
- Centre for Heart Lung Innovation, University of British Columbia and St. Paul's Hospital, 1081 Burrard Street, Vancouver, BC, V6Z 1Y6, Canada.
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Hodik M, Skog O, Lukinius A, Isaza-Correa JM, Kuipers J, Giepmans BNG, Frisk G. Enterovirus infection of human islets of Langerhans affects β-cell function resulting in disintegrated islets, decreased glucose stimulated insulin secretion and loss of Golgi structure. BMJ Open Diabetes Res Care 2016; 4:e000179. [PMID: 27547409 PMCID: PMC4985798 DOI: 10.1136/bmjdrc-2015-000179] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Revised: 04/27/2016] [Accepted: 05/02/2016] [Indexed: 12/16/2022] Open
Abstract
AIMS/HYPOTHESIS In type 1 diabetes (T1D), most insulin-producing β cells are destroyed, but the trigger is unknown. One of the possible triggers is a virus infection and the aim of this study was to test if enterovirus infection affects glucose stimulated insulin secretion and the effect of virus replication on cellular macromolecules and organelles involved in insulin secretion. METHODS Isolated human islets were infected with different strains of coxsackievirus B (CVB) virus and the glucose-stimulated insulin release (GSIS) was measured in a dynamic perifusion system. Classical morphological electron microscopy, large-scale electron microscopy, so-called nanotomy, and immunohistochemistry were used to study to what extent virus-infected β cells contained insulin, and real-time PCR was used to analyze virus induced changes of islet specific genes. RESULTS In islets infected with CVB, GSIS was reduced in correlation with the degree of virus-induced islet disintegration. The expression of the gene encoding insulin was decreased in infected islets, whereas the expression of glucagon was not affected. Also, in islets that were somewhat disintegrated, there were uninfected β cells. Ultrastructural analysis revealed that virus particles and virus replication complexes were only present in β cells. There was a significant number of insulin granules remaining in the virus-infected β cells, despite decreased expression of insulin mRNA. In addition, no typical Golgi apparatus was detected in these cells. Exposure of islets to synthetic dsRNA potentiated glucose-stimulated insulin secretion. CONCLUSIONS/INTERPRETATION Glucose-stimulated insulin secretion; organelles involved in insulin secretion and gene expression were all affected by CVB replication in β cells.
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Affiliation(s)
- M Hodik
- Department of Immunology, Genetics and Pathology, The Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - O Skog
- Department of Immunology, Genetics and Pathology, The Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - A Lukinius
- Department of Immunology, Genetics and Pathology, The Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - J M Isaza-Correa
- Department of Cell Biology, University Medical Center Groningen, University Groningen, Groningen, The Netherlands
| | - J Kuipers
- Department of Cell Biology, University Medical Center Groningen, University Groningen, Groningen, The Netherlands
| | - B N G Giepmans
- Department of Cell Biology, University Medical Center Groningen, University Groningen, Groningen, The Netherlands
| | - G Frisk
- Department of Immunology, Genetics and Pathology, The Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
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Perry JL, Ramachandran NK, Utama B, Hyser JM. Use of genetically-encoded calcium indicators for live cell calcium imaging and localization in virus-infected cells. Methods 2015; 90:28-38. [PMID: 26344758 PMCID: PMC4655165 DOI: 10.1016/j.ymeth.2015.09.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2015] [Revised: 08/31/2015] [Accepted: 09/01/2015] [Indexed: 01/09/2023] Open
Abstract
Calcium signaling is a ubiquitous and versatile process involved in nearly every cellular process, and exploitation of host calcium signals is a common strategy used by viruses to facilitate replication and cause disease. Small molecule fluorescent calcium dyes have been used by many to examine changes in host cell calcium signaling and calcium channel activation during virus infections, but disadvantages of these dyes, including poor loading and poor long-term retention, complicate analysis of calcium imaging in virus-infected cells due to changes in cell physiology and membrane integrity. The recent expansion of genetically-encoded calcium indicators (GECIs), including blue and red-shifted color variants and variants with calcium affinities appropriate for calcium storage organelles like the endoplasmic reticulum (ER), make the use of GECIs an attractive alternative for calcium imaging in the context of virus infections. Here we describe the development and testing of cell lines stably expressing both green cytoplasmic (GCaMP5G and GCaMP6s) and red ER-targeted (RCEPIAer) GECIs. Using three viruses (rotavirus, poliovirus and respiratory syncytial virus) previously shown to disrupt host calcium homeostasis, we show the GECI cell lines can be used to detect simultaneous cytoplasmic and ER calcium signals. Further, we demonstrate the GECI expression has sufficient stability to enable long-term confocal imaging of both cytoplasmic and ER calcium during the course of virus infections.
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Affiliation(s)
- Jacob L Perry
- Department of Molecular Virology and Microbiology and Alkek Center for Metagenomic and Microbiome Research, Baylor College of Medicine, Houston, TX 77030, United States
| | - Nina K Ramachandran
- Department of Molecular Virology and Microbiology and Alkek Center for Metagenomic and Microbiome Research, Baylor College of Medicine, Houston, TX 77030, United States
| | - Budi Utama
- Shared Equipment Authority, Rice University, Houston, TX 77030, United States
| | - Joseph M Hyser
- Department of Molecular Virology and Microbiology and Alkek Center for Metagenomic and Microbiome Research, Baylor College of Medicine, Houston, TX 77030, United States.
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48
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McGinty JW, Marré ML, Bajzik V, Piganelli JD, James EA. T cell epitopes and post-translationally modified epitopes in type 1 diabetes. Curr Diab Rep 2015; 15:90. [PMID: 26370701 PMCID: PMC4902156 DOI: 10.1007/s11892-015-0657-7] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Type 1 diabetes (T1D) is an autoimmune disease in which progressive loss of self-tolerance, evidenced by accumulation of auto-antibodies and auto-reactive T cells that recognize diverse self-proteins, leads to immune-mediated destruction of pancreatic beta cells and loss of insulin secretion. In this review, we discuss antigens and epitopes in T1D and the role that post-translational modifications play in circumventing tolerance mechanisms and increasing antigenic diversity. Emerging data suggest that, analogous to other autoimmune diseases such as rheumatoid arthritis and celiac disease, enzymatically modified epitopes are preferentially recognized in T1D. Modifying enzymes such as peptidyl deiminases and tissue transglutaminase are activated in response to beta cell stress, providing a mechanistic link between post-translational modification and interactions with the environment. Although studies of such responses in the at-risk population have been limited, current data suggests that breakdown in tolerance through post-translational modification represents an important checkpoint in the development of T1D.
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Affiliation(s)
- John W McGinty
- Benaroya Research Institute at Virginia Mason, 1201 9th Ave, Seattle, WA, USA.
| | - Meghan L Marré
- Children's Hospital of Pittsburgh, University of Pittsburgh, 4401 Penn Avenue, Pittsburgh, PA, USA.
| | - Veronique Bajzik
- Benaroya Research Institute at Virginia Mason, 1201 9th Ave, Seattle, WA, USA.
| | - Jon D Piganelli
- Children's Hospital of Pittsburgh, University of Pittsburgh, 4401 Penn Avenue, Pittsburgh, PA, USA.
| | - Eddie A James
- Benaroya Research Institute at Virginia Mason, 1201 9th Ave, Seattle, WA, USA.
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The C-terminal region of the non-structural protein 2B from Hepatitis A Virus demonstrates lipid-specific viroporin-like activity. Sci Rep 2015; 5:15884. [PMID: 26515753 PMCID: PMC4626808 DOI: 10.1038/srep15884] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2015] [Accepted: 10/05/2015] [Indexed: 12/20/2022] Open
Abstract
Viroporins are virally encoded, membrane-active proteins, which enhance viral replication and assist in egress of viruses from host cells. The 2B proteins in the picornaviridae family are known to have viroporin-like properties, and play critical roles during virus replication. The 2B protein of Hepatitis A Virus (2B), an unusual picornavirus, is somewhat dissimilar from its analogues in several respects. HAV 2B is approximately 2.5 times the length of other 2B proteins, and does not disrupt calcium homeostasis or glycoprotein trafficking. Additionally, its membrane penetrating properties are not yet clearly established. Here we show that the membrane interacting activity of HAV 2B is localized in its C-terminal region, which contains an alpha-helical hairpin motif. We show that this region is capable of forming small pores in membranes and demonstrates lipid specific activity, which partially rationalizes the intracellular localization of full-length 2B. Using a combination of biochemical assays and molecular dynamics simulation studies, we also show that HAV 2B demonstrates a marked propensity to dimerize in a crowded environment, and probably interacts with membranes in a multimeric form, a hallmark of other picornavirus viroporins. In sum, our study clearly establishes HAV 2B as a bona fide viroporin in the picornaviridae family.
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50
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Calcium Regulation of Hemorrhagic Fever Virus Budding: Mechanistic Implications for Host-Oriented Therapeutic Intervention. PLoS Pathog 2015; 11:e1005220. [PMID: 26513362 PMCID: PMC4634230 DOI: 10.1371/journal.ppat.1005220] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Accepted: 09/21/2015] [Indexed: 12/19/2022] Open
Abstract
Hemorrhagic fever viruses, including the filoviruses (Ebola and Marburg) and arenaviruses (Lassa and Junín viruses), are serious human pathogens for which there are currently no FDA approved therapeutics or vaccines. Importantly, transmission of these viruses, and specifically late steps of budding, critically depend upon host cell machinery. Consequently, strategies which target these mechanisms represent potential targets for broad spectrum host oriented therapeutics. An important cellular signal implicated previously in EBOV budding is calcium. Indeed, host cell calcium signals are increasingly being recognized to play a role in steps of entry, replication, and transmission for a range of viruses, but if and how filoviruses and arenaviruses mobilize calcium and the precise stage of virus transmission regulated by calcium have not been defined. Here we demonstrate that expression of matrix proteins from both filoviruses and arenaviruses triggers an increase in host cytoplasmic Ca2+ concentration by a mechanism that requires host Orai1 channels. Furthermore, we demonstrate that Orai1 regulates both VLP and infectious filovirus and arenavirus production and spread. Notably, suppression of the protein that triggers Orai activation (Stromal Interaction Molecule 1, STIM1) and genetic inactivation or pharmacological blockade of Orai1 channels inhibits VLP and infectious virus egress. These findings are highly significant as they expand our understanding of host mechanisms that may broadly control enveloped RNA virus budding, and they establish Orai and STIM1 as novel targets for broad-spectrum host-oriented therapeutics to combat these emerging BSL-4 pathogens and potentially other enveloped RNA viruses that bud via similar mechanisms. Filoviruses (Ebola and Marburg viruses) and arenaviruses (Lassa and Junín viruses) are high-priority pathogens that hijack host proteins and pathways to complete their replication cycles and spread from cell to cell. Here we provide genetic and pharmacological evidence to demonstrate that the host calcium channel protein Orai1 and ER calcium sensor protein STIM1 regulate efficient budding and spread of BSL-4 pathogens Ebola, Marburg, Lassa, and Junín viruses. Our findings are of broad significance as they provide new mechanistic insight into fundamental, immutable, and conserved mechanisms of hemorrhagic fever virus pathogenesis. Moreover, this strategy of targeting highly conserved host cellular protein(s) and mechanisms required by these viruses to complete their life cycle should elicit minimal drug resistance.
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