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Bagnéris C, Senthil Kumar SL, Baratchian M, Britt HM, Assafa TE, Thalassinos K, Collins MK, Barrett TE. Mechanistic insights into the activation of the IKK kinase complex by the Kaposi's Sarcoma Herpes virus oncoprotein vFLIP. J Biol Chem 2022; 298:102012. [PMID: 35525271 PMCID: PMC9163697 DOI: 10.1016/j.jbc.2022.102012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 04/27/2022] [Accepted: 04/28/2022] [Indexed: 11/23/2022] Open
Abstract
Constitutive activation of the canonical NF-κB signaling pathway is a major factor in Kaposi’s sarcoma-associated herpes virus pathogenesis where it is essential for the survival of primary effusion lymphoma. Central to this process is persistent upregulation of the inhibitor of κB kinase (IKK) complex by the virally encoded oncoprotein vFLIP. Although the physical interaction between vFLIP and the IKK kinase regulatory component essential for persistent activation, IKKγ, has been well characterized, it remains unclear how the kinase subunits are rendered active mechanistically. Using a combination of cell-based assays, biophysical techniques, and structural biology, we demonstrate here that vFLIP alone is sufficient to activate the IKK kinase complex. Furthermore, we identify weakly stabilized, high molecular weight vFLIP–IKKγ assemblies that are key to the activation process. Taken together, our results are the first to reveal that vFLIP-induced NF-κB activation pivots on the formation of structurally specific vFLIP–IKKγ multimers which have an important role in rendering the kinase subunits active through a process of autophosphorylation. This mechanism of NF-κB activation is in contrast to those utilized by endogenous cytokines and cellular FLIP homologues.
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Affiliation(s)
- Claire Bagnéris
- Department of Biological Sciences, Institute of Structural Molecular Biology, Birkbeck College, London, UK
| | - Swathi L Senthil Kumar
- Department of Biological Sciences, Institute of Structural Molecular Biology, Birkbeck College, London, UK
| | - Mehdi Baratchian
- Genitourinary Malignancies Research Center, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Hannah M Britt
- Division of Biosciences, Institute of Structural and Molecular Biology, University College London, London, UK
| | - Tufa E Assafa
- Chemistry and Biochemistry Department, University of California Santa Cruz, Santa Cruz, California, USA
| | - Konstantinos Thalassinos
- Department of Biological Sciences, Institute of Structural Molecular Biology, Birkbeck College, London, UK; Division of Biosciences, Institute of Structural and Molecular Biology, University College London, London, UK
| | - Mary K Collins
- Okinawa Institute of Science and Technology, Graduate University, Onna-son, Okinawa, Japan
| | - Tracey E Barrett
- Department of Biological Sciences, Institute of Structural Molecular Biology, Birkbeck College, London, UK.
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2
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Jiang H, Kan X, Ding C, Sun Y. The Multi-Faceted Role of Autophagy During Animal Virus Infection. Front Cell Infect Microbiol 2022; 12:858953. [PMID: 35402295 PMCID: PMC8990858 DOI: 10.3389/fcimb.2022.858953] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 03/01/2022] [Indexed: 01/17/2023] Open
Abstract
Autophagy is a process of degradation to maintain cellular homeostatic by lysosomes, which ensures cellular survival under various stress conditions, including nutrient deficiency, hypoxia, high temperature, and pathogenic infection. Xenophagy, a form of selective autophagy, serves as a defense mechanism against multiple intracellular pathogen types, such as viruses, bacteria, and parasites. Recent years have seen a growing list of animal viruses with autophagy machinery. Although the relationship between autophagy and human viruses has been widely summarized, little attention has been paid to the role of this cellular function in the veterinary field, especially today, with the growth of serious zoonotic diseases. The mechanisms of the same virus inducing autophagy in different species, or different viruses inducing autophagy in the same species have not been clarified. In this review, we examine the role of autophagy in important animal viral infectious diseases and discuss the regulation mechanisms of different animal viruses to provide a potential theoretical basis for therapeutic strategies, such as targets of new vaccine development or drugs, to improve industrial production in farming.
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Affiliation(s)
- Hui Jiang
- Department of Avian Infectious Diseases, Shanghai Veterinary Research Institute. Chinese Academy of Agricultural Science, Shanghai, China
| | - Xianjin Kan
- Department of Avian Infectious Diseases, Shanghai Veterinary Research Institute. Chinese Academy of Agricultural Science, Shanghai, China
| | - Chan Ding
- Department of Avian Infectious Diseases, Shanghai Veterinary Research Institute. Chinese Academy of Agricultural Science, Shanghai, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, China
- *Correspondence: Yingjie Sun, ; Chan Ding,
| | - Yingjie Sun
- Department of Avian Infectious Diseases, Shanghai Veterinary Research Institute. Chinese Academy of Agricultural Science, Shanghai, China
- *Correspondence: Yingjie Sun, ; Chan Ding,
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Choi YB, Cousins E, Nicholas J. Novel Functions and Virus-Host Interactions Implicated in Pathogenesis and Replication of Human Herpesvirus 8. Recent Results Cancer Res 2021; 217:245-301. [PMID: 33200369 DOI: 10.1007/978-3-030-57362-1_11] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Human herpesvirus 8 (HHV-8) is classified as a γ2-herpesvirus and is related to Epstein-Barr virus (EBV), a γ1-herpesvirus. One important aspect of the γ-herpesviruses is their association with neoplasia, either naturally or in animal model systems. HHV-8 is associated with B-cell-derived primary effusion lymphoma (PEL) and multicentric Castleman's disease (MCD), endothelial-derived Kaposi's sarcoma (KS), and KSHV inflammatory cytokine syndrome (KICS). EBV is also associated with a number of B-cell malignancies, such as Burkitt's lymphoma, Hodgkin's lymphoma, and posttransplant lymphoproliferative disease, in addition to epithelial nasopharyngeal and gastric carcinomas. Despite the similarities between these viruses and their associated malignancies, the particular protein functions and activities involved in key aspects of virus biology and neoplastic transformation appear to be quite distinct. Indeed, HHV-8 specifies a number of proteins for which counterparts had not previously been identified in EBV, other herpesviruses, or even viruses in general, and these proteins are believed to play vital functions in virus biology and to be involved centrally in viral pathogenesis. Additionally, a set of microRNAs encoded by HHV-8 appears to modulate the expression of multiple host proteins to provide conditions conductive to virus persistence within the host and possibly contributing to HHV-8-induced neoplasia. Here, we review the molecular biology underlying these novel virus-host interactions and their potential roles in both virus biology and virus-associated disease.
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Affiliation(s)
- Young Bong Choi
- Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Department of Oncology, Johns Hopkins University School of Medicine, 1650 Orleans Street, Baltimore, MD, 21287, USA.
| | - Emily Cousins
- Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Department of Oncology, Johns Hopkins University School of Medicine, 1650 Orleans Street, Baltimore, MD, 21287, USA
| | - John Nicholas
- Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Department of Oncology, Johns Hopkins University School of Medicine, 1650 Orleans Street, Baltimore, MD, 21287, USA
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4
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Interactions between Autophagy and DNA Viruses. Viruses 2019; 11:v11090776. [PMID: 31450758 PMCID: PMC6784137 DOI: 10.3390/v11090776] [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: 08/01/2019] [Revised: 08/15/2019] [Accepted: 08/19/2019] [Indexed: 02/07/2023] Open
Abstract
Autophagy is a catabolic biological process in the body. By targeting exogenous microorganisms and aged intracellular proteins and organelles and sending them to the lysosome for phagocytosis and degradation, autophagy contributes to energy recycling. When cells are stimulated by exogenous pathogenic microorganisms such as viruses, activation or inhibition of autophagy is often triggered. As autophagy has antiviral effects, many viruses may escape and resist the process by encoding viral proteins. At the same time, viruses can also use autophagy to enhance their replication or increase the persistence of latent infections. Here, we give a brief overview of autophagy and DNA viruses and comprehensively review the known interactions between human and animal DNA viruses and autophagy and the role and mechanisms of autophagy in viral DNA replication and DNA virus-induced innate and acquired immunity.
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Reichert M, Lukasik A, Zielenkiewicz P, Matras M, Maj-Paluch J, Stachnik M, Borzym E. Host microRNA analysis in cyprinid Herpesvirus-3 (CyHV-3) infected common carp. BMC Genomics 2019; 20:46. [PMID: 30654758 PMCID: PMC6337785 DOI: 10.1186/s12864-018-5266-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Accepted: 11/19/2018] [Indexed: 12/15/2022] Open
Abstract
Background The mechanism of latency and the ability of the cyprinid herpesvirus 3 (CyHV-3) to establish life-long infections in carp remains poorly understood. To explain the role of miRNAs in this process we applied a range of molecular tools including high-throughput sequencing of RNA libraries constructed from the blood samples of infected fish followed by bioinformatic and functional analyses which show that CyHV-3 profoundly influences the expression of host miRNAs in vivo. Results We demonstrated the changed expression of 27 miRNAs in the clinical phase and 5 in the latent phase of infection. We also identified 23 novel, not previously reported sequences, from which 8 showed altered expressions in control phase, 10 in clinical phase and 5 in latent phase of infection. Conclusions The results of our analysis expand the knowledge of common carp microRNAs engaged during CyHV-3 infection and provide a useful basis for the further study of the mechanism of CyHV-3 induced pathology. Electronic supplementary material The online version of this article (10.1186/s12864-018-5266-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Michal Reichert
- Department of Fish Diseases, National Veterinary Research Institute, 57 Partyzantow Avenue, 24-100, Pulawy, Poland.
| | - Anna Lukasik
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, 02-106, Warsaw, Poland
| | - Piotr Zielenkiewicz
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, 02-106, Warsaw, Poland.,Department of Plant Molecular Biology, Institute of Experimental Plant Biology and Biotechnology, University of Warsaw, 02-096, Warsaw, Poland
| | - Marek Matras
- Department of Fish Diseases, National Veterinary Research Institute, 57 Partyzantow Avenue, 24-100, Pulawy, Poland
| | - Joanna Maj-Paluch
- Department of Fish Diseases, National Veterinary Research Institute, 57 Partyzantow Avenue, 24-100, Pulawy, Poland
| | - Magdalena Stachnik
- Department of Fish Diseases, National Veterinary Research Institute, 57 Partyzantow Avenue, 24-100, Pulawy, Poland
| | - Ewa Borzym
- Department of Fish Diseases, National Veterinary Research Institute, 57 Partyzantow Avenue, 24-100, Pulawy, Poland
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Chu BX, Fan RF, Lin SQ, Yang DB, Wang ZY, Wang L. Interplay between autophagy and apoptosis in lead(II)-induced cytotoxicity of primary rat proximal tubular cells. J Inorg Biochem 2018; 182:184-193. [DOI: 10.1016/j.jinorgbio.2018.02.015] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 02/18/2018] [Accepted: 02/19/2018] [Indexed: 12/13/2022]
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Lussignol M, Esclatine A. Herpesvirus and Autophagy: "All Right, Everybody Be Cool, This Is a Robbery!". Viruses 2017; 9:v9120372. [PMID: 29207540 PMCID: PMC5744147 DOI: 10.3390/v9120372] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 11/26/2017] [Accepted: 11/27/2017] [Indexed: 12/20/2022] Open
Abstract
Autophagy is an essential vacuolar process of the cell, leading to lysosomal degradation and recycling of proteins and organelles, which is extremely important in maintaining homeostasis. Multiple roles have been now associated with autophagy, in particular a pro-survival role in nutrient starvation or in stressful environments, a role in life span extension, in development, or in innate and adaptive immunity. This cellular process can also take over microorganisms or viral proteins inside autophagosomes and degrade them directly in autolysosomes and is then called xenophagy and virophagy, respectively. Several Herpesviruses have developed strategies to escape this degradation, by expression of specific anti-autophagic proteins. However, we are increasingly discovering that Herpesviruses hijack autophagy, rather than just fight it. This beneficial effect is obvious since inhibition of autophagy will lead to decreased viral titers for human cytomegalovirus (HCMV), Epstein-Barr virus (EBV) or Varicella-Zoster virus (VZV), for example. Conversely, autophagy stimulation will improve viral multiplication. The autophagic machinery can be used in whole or in part, and can optimize viral propagation or persistence. Some viruses block maturation of autophagosomes to avoid the degradation step, then autophagosomal membranes are used to contribute to the envelopment and/or the egress of viral particles. On the other hand, VZV stimulates the whole process of autophagy to subvert it in order to use vesicles containing ATG (autophagy-related) proteins and resembling amphisomes for their transport in the cytoplasm. During latency, autophagy can also be activated by latent proteins encoded by different oncogenic Herpesviruses to promote cell survival and achieve long term viral persistence in vivo. Finally, reactivation of gammaherpesvirus Murid Herpesvirus 68 (MHV68) in mice appears to be positively modulated by autophagy, in order to control the level of inflammation. Therefore, Herpesviruses appear to behave more like thieves than fugitives.
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Affiliation(s)
- Marion Lussignol
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette Cedex, France.
| | - Audrey Esclatine
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette Cedex, France.
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Banerjee S, Uppal T, Strahan R, Dabral P, Verma SC. The Modulation of Apoptotic Pathways by Gammaherpesviruses. Front Microbiol 2016; 7:585. [PMID: 27199919 PMCID: PMC4847483 DOI: 10.3389/fmicb.2016.00585] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2016] [Accepted: 04/11/2016] [Indexed: 12/11/2022] Open
Abstract
Apoptosis or programmed cell death is a tightly regulated process fundamental for cellular development and elimination of damaged or infected cells during the maintenance of cellular homeostasis. It is also an important cellular defense mechanism against viral invasion. In many instances, abnormal regulation of apoptosis has been associated with a number of diseases, including cancer development. Following infection of host cells, persistent and oncogenic viruses such as the members of the Gammaherpesvirus family employ a number of different mechanisms to avoid the host cell’s “burglar” alarm and to alter the extrinsic and intrinsic apoptotic pathways by either deregulating the expressions of cellular signaling genes or by encoding the viral homologs of cellular genes. In this review, we summarize the recent findings on how gammaherpesviruses inhibit cellular apoptosis via virus-encoded proteins by mediating modification of numerous signal transduction pathways. We also list the key viral anti-apoptotic proteins that could be exploited as effective targets for novel antiviral therapies in order to stimulate apoptosis in different types of cancer cells.
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Affiliation(s)
- Shuvomoy Banerjee
- Amity Institute of Virology and Immunology, Amity University Noida, India
| | - Timsy Uppal
- Department of Microbiology and Immunology, Center for Molecular Medicine, School of Medicine, University of Nevada, Reno Reno, NV, USA
| | - Roxanne Strahan
- Department of Microbiology and Immunology, Center for Molecular Medicine, School of Medicine, University of Nevada, Reno Reno, NV, USA
| | - Prerna Dabral
- Department of Microbiology and Immunology, Center for Molecular Medicine, School of Medicine, University of Nevada, Reno Reno, NV, USA
| | - Subhash C Verma
- Department of Microbiology and Immunology, Center for Molecular Medicine, School of Medicine, University of Nevada, Reno Reno, NV, USA
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Jia Z, Liu Y, Su H, Li M, Zhang M, Zhu Y, Li T, Fang Y, Liang S. Safflower extract inhibiting apoptosis by inducing autophagy in myocardium derived H9C2 cell. Int J Clin Exp Med 2015; 8:20254-20262. [PMID: 26884938 PMCID: PMC4723783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 10/28/2015] [Indexed: 06/05/2023]
Abstract
The Heart failure (HF) is considered as the end-stage of various heart disease and associated with high mortality globally. Progressive loss of cardiac myocytes via apoptosis is considered as the most important factor for HF pathology. In this study, we demonstrated that Safflower extract was able to inhibitthe apoptosis inducted by Angiotensin II (AngII) in a ratmyocardium derived cell line H9C2. Further examination of LC-3II conversion and autophagosome formation suggested Safflower extract induced autophagy in treated cell. Inhibition of Safflower extract induced autophagy by 3-methyladenine (3MA) abolished anti-apoptotic function of Safflower extract, while application of autophagy stimulator Rapamycin in H9C2 inhibited apoptosis as well. Moreover, treatment of H9C2 cell with Safflower extract also inhibited expression of pro-apoptotic genes BAD and Bax. In conclusion, our data indicated that Safflower extract inhibit apoptosis via inducing autophagy in myocardium cell and demonstrated the potential as novel therapeutic drug for Heart failure.
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Affiliation(s)
- Zhisheng Jia
- Department of Cardiology, The Fifth People's Hospital of Jinan City Jinan 250022, Shandong, China
| | - Yancai Liu
- Department of Cardiology, The Fifth People's Hospital of Jinan City Jinan 250022, Shandong, China
| | - Huailing Su
- Department of Cardiology, The Fifth People's Hospital of Jinan City Jinan 250022, Shandong, China
| | - Ming Li
- Department of Cardiology, The Fifth People's Hospital of Jinan City Jinan 250022, Shandong, China
| | - Min Zhang
- Department of Cardiology, The Fifth People's Hospital of Jinan City Jinan 250022, Shandong, China
| | - Ye Zhu
- Department of Cardiology, The Fifth People's Hospital of Jinan City Jinan 250022, Shandong, China
| | - Tenjiao Li
- Department of Cardiology, The Fifth People's Hospital of Jinan City Jinan 250022, Shandong, China
| | - Youbo Fang
- Department of Cardiology, The Fifth People's Hospital of Jinan City Jinan 250022, Shandong, China
| | - Shimin Liang
- Department of Cardiology, The Fifth People's Hospital of Jinan City Jinan 250022, Shandong, China
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Lu CL, Xu J, Yao HJ, Luo KL, Li JM, Wu T, Wu GZ. Inhibition of human 67-kDa laminin receptor sensitizes multidrug resistance colon cancer cell line SW480 for apoptosis induction. Tumour Biol 2015; 37:1319-25. [PMID: 26293895 DOI: 10.1007/s13277-015-3873-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 07/30/2015] [Indexed: 11/26/2022] Open
Abstract
The adhesion mediated drug resistance in cancer cells resulted from adhesion of the extracellular matrix is a major cause for multidrug resistance (MDR) and leads chemotherapeutic failure for colon cancer. In this study, we explored the role of 67-kDa laminin receptor (67LR) in chemotherapeutic drug resistance in colon cancer cells. SiRNA-mediated knockdown of 67LR decreased the cell adhesion when laminins were applied. Moreover, 67LR knockdown increased the expression of pro-apoptotic gene Bax but inhibited the expression of anti-apoptotic gene Bcl-2. Enhanced apoptosis was observed in 67LR siRNA-transfected SW480 cell when the cell was treated with doxorubicin for apoptosis induction. Furthermore, MTT assay revealed that the IC50 of chemotherapeutic toward SW480 cell adhesion to laminins was reduced after 67LR knockdown, indicating there was a significant increase of drug sensitivity in SW480 cell. In conclusion, our study demonstrated that 67LR plays a considerable role in the development of colon cancer MDR.
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Affiliation(s)
- Chun-Lei Lu
- Department of Gastrointestinal Surgery, No. 101 Hospital of PLA, No. 101, Xingyuan Bei Road, Wuxi, Jiangsu, 214044, China.
| | - Jian Xu
- Department of Gastrointestinal Surgery, No. 101 Hospital of PLA, No. 101, Xingyuan Bei Road, Wuxi, Jiangsu, 214044, China
| | - Hao-Jie Yao
- Department of Gastrointestinal Surgery, No. 101 Hospital of PLA, No. 101, Xingyuan Bei Road, Wuxi, Jiangsu, 214044, China
| | - Kun-Lun Luo
- Department of Gastrointestinal Surgery, No. 101 Hospital of PLA, No. 101, Xingyuan Bei Road, Wuxi, Jiangsu, 214044, China
| | - Jie-Ming Li
- Department of Gastrointestinal Surgery, No. 101 Hospital of PLA, No. 101, Xingyuan Bei Road, Wuxi, Jiangsu, 214044, China
| | - Tao Wu
- Department of Gastrointestinal Surgery, No. 101 Hospital of PLA, No. 101, Xingyuan Bei Road, Wuxi, Jiangsu, 214044, China
| | - Guo-Zhong Wu
- Department of Gastrointestinal Surgery, No. 101 Hospital of PLA, No. 101, Xingyuan Bei Road, Wuxi, Jiangsu, 214044, China.
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Buskiewicz IA, Koenig A, Roberts B, Russell J, Shi C, Lee SH, Jung JU, Huber SA, Budd RC. c-FLIP-Short reduces type I interferon production and increases viremia with coxsackievirus B3. PLoS One 2014; 9:e96156. [PMID: 24816846 PMCID: PMC4015977 DOI: 10.1371/journal.pone.0096156] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Accepted: 04/03/2014] [Indexed: 11/19/2022] Open
Abstract
Cellular FLIP (c-FLIP) is an enzymatically inactive paralogue of caspase-8 and as such can block death receptor-induced apoptosis. However, independent of death receptors, c-FLIP-Long (c-FLIPL) can heterodimerize with and activate caspase-8. This is critical for promoting the growth and survival of T lymphocytes as well as the regulation of the RIG-I helicase pathway for type I interferon production in response to viral infections. Truncated forms of FLIP also exist in mammalian cells (c-FLIPS) and certain viruses (v-FLIP), which lack the C-terminal domain that activates caspase-8. Thus, the ratio of c-FLIPL to these short forms of FLIP may greatly influence the outcome of an immune response. We examined this model in mice transgenically expressing c-FLIPS in T cells during infection with Coxsackievirus B3 (CVB3). In contrast to our earlier findings of reduced myocarditis and mortality with CVB3 infection of c-FLIPL-transgenic mice, c-FLIPS-transgenic mice were highly sensitive to CVB3 infection as manifested by increased cardiac virus titers, myocarditis score, and mortality compared to wild-type C57BL/6 mice. This observation was paralleled by a reduction in serum levels of IL-10 and IFN-α in CVB3-infected c-FLIPS mice. In vitro infection of c-FLIPS T cells with CVB3 confirmed these results. Furthermore, molecular studies revealed that following infection of cells with CVB3, c-FLIPL associates with mitochondrial antiviral signaling protein (MAVS), increases caspase-8 activity and type I IFN production, and reduces viral replication, whereas c-FLIPS promotes the opposite phenotype.
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Affiliation(s)
- Iwona A. Buskiewicz
- Department of Pathology, Vermont Center for Immunology and Infectious Diseases, University of Vermont, Burlington, Vermont, United States of America
- * E-mail:
| | - Andreas Koenig
- Department of Medicine, Vermont Center for Immunology and Infectious Diseases, University of Vermont, Burlington, Vermont, United States of America
| | - Brian Roberts
- Department of Pathology, Vermont Center for Immunology and Infectious Diseases, University of Vermont, Burlington, Vermont, United States of America
| | - Jennifer Russell
- Department of Medicine, Vermont Center for Immunology and Infectious Diseases, University of Vermont, Burlington, Vermont, United States of America
| | - Cuixia Shi
- Department of Medicine, Vermont Center for Immunology and Infectious Diseases, University of Vermont, Burlington, Vermont, United States of America
| | - Sun-Hwa Lee
- Department of Molecular Microbiology and Immunology, University of Southern California, Los Angeles, California, United States of America.
| | - Jae U. Jung
- Department of Molecular Microbiology and Immunology, University of Southern California, Los Angeles, California, United States of America.
| | - Sally A. Huber
- Department of Pathology, Vermont Center for Immunology and Infectious Diseases, University of Vermont, Burlington, Vermont, United States of America
| | - Ralph C. Budd
- Department of Medicine, Vermont Center for Immunology and Infectious Diseases, University of Vermont, Burlington, Vermont, United States of America
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Commentary on the regulation of viral proteins in autophagy process. BIOMED RESEARCH INTERNATIONAL 2014; 2014:962915. [PMID: 24734254 PMCID: PMC3966343 DOI: 10.1155/2014/962915] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Accepted: 02/04/2014] [Indexed: 12/25/2022]
Abstract
The ability to subvert intracellular antiviral defenses is necessary for virus to survive as its replication occurs only in the host cells. Viruses have to modulate cellular processes and antiviral mechanisms to their own advantage during the entire virus life cycle. Autophagy plays important roles in cell regulation. Its function is not only to catabolize aggregate proteins and damaged organelles for recycling but also to serve as innate immunity to remove intracellular pathogenic elements such as viruses. Nevertheless, some viruses have evolved to negatively regulate autophagy by inhibiting its formation. Even more, some viruses have employed autophagy to benefit their replication. To date, there are more and more growing evidences uncovering the functions of many viral proteins to regulate autophagy through different cellular pathways. In this review, we will discuss the relationship between viruses and autophagy and summarize the current knowledge on the functions of viral proteins contributing to affect autophagy process.
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The role of sex differences in autophagy in the heart during coxsackievirus B3-induced myocarditis. J Cardiovasc Transl Res 2013; 7:182-91. [PMID: 24323874 DOI: 10.1007/s12265-013-9525-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Accepted: 11/20/2013] [Indexed: 12/28/2022]
Abstract
Under normal conditions, autophagy maintains cardiomyocyte health and integrity through turnover of organelles. During stress, oxygen and nutrient deprivation, or microbial infection, autophagy prolongs cardiomyocyte survival. Sex differences in induction of cell death may to some extent explain the disparity between the sexes in many human diseases. However, sex differences in gene expression, which regulate cell death and autophagy, were so far not taken in consideration to explain the sex bias of viral myocarditis. Coxsackievirus B3 (CVB3)-induced myocarditis is a sex-biased disease, with females being substantially less susceptible than males and sex hormones largely determine this bias. CVB3 was shown to induce and subvert the autophagosome for its optimal viral RNA replication. Gene expression analysis on mouse and human, healthy and CVB3-infected, cardiac samples of both sexes, suggests sex differences in autophagy-related gene expression. This review discusses the aspects of sex bias in autophagy induction in cardiomyocytes.
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14
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Tovilovic G, Ristic B, Milenkovic M, Stanojevic M, Trajkovic V. The Role and Therapeutic Potential of Autophagy Modulation in Controlling Virus-Induced Cell Death. Med Res Rev 2013; 34:744-67. [DOI: 10.1002/med.21303] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Gordana Tovilovic
- Institute for Biological Research; University of Belgrade; Despot Stefan Boulevard 142 11000 Belgrade Serbia
| | - Biljana Ristic
- Institute of Microbiology and Immunology; School of Medicine; University of Belgrade; Dr. Subotica 1 11000 Belgrade Serbia
| | - Marina Milenkovic
- Institute of Microbiology and Immunology; School of Medicine; University of Belgrade; Dr. Subotica 1 11000 Belgrade Serbia
| | - Maja Stanojevic
- Institute of Microbiology and Immunology; School of Medicine; University of Belgrade; Dr. Subotica 1 11000 Belgrade Serbia
| | - Vladimir Trajkovic
- Institute of Microbiology and Immunology; School of Medicine; University of Belgrade; Dr. Subotica 1 11000 Belgrade Serbia
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