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Wan Q, Tavakoli L, Wang TY, Tucker AJ, Zhou R, Liu Q, Feng S, Choi D, He Z, Gack MU, Zhao J. Hijacking of nucleotide biosynthesis and deamidation-mediated glycolysis by an oncogenic herpesvirus. Nat Commun 2024; 15:1442. [PMID: 38365882 PMCID: PMC10873312 DOI: 10.1038/s41467-024-45852-5] [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: 06/21/2023] [Accepted: 02/05/2024] [Indexed: 02/18/2024] Open
Abstract
Kaposi's sarcoma-associated herpesvirus (KSHV) is the causative agent of Kaposi's sarcoma (KS) and multiple types of B cell malignancies. Emerging evidence demonstrates that KSHV reprograms host-cell central carbon metabolic pathways, which contributes to viral persistence and tumorigenesis. However, the mechanisms underlying KSHV-mediated metabolic reprogramming remain poorly understood. Carbamoyl-phosphate synthetase 2, aspartate transcarbamoylase, and dihydroorotase (CAD) is a key enzyme of the de novo pyrimidine synthesis, and was recently identified to deamidate the NF-κB subunit RelA to promote aerobic glycolysis and cell proliferation. Here we report that KSHV infection exploits CAD for nucleotide synthesis and glycolysis. Mechanistically, KSHV vCyclin binds to and hijacks cyclin-dependent kinase CDK6 to phosphorylate Ser-1900 on CAD, thereby activating CAD-mediated pyrimidine synthesis and RelA-deamidation-mediated glycolytic reprogramming. Correspondingly, genetic depletion or pharmacological inhibition of CDK6 and CAD potently impeded KSHV lytic replication and thwarted tumorigenesis of primary effusion lymphoma (PEL) cells in vitro and in vivo. Altogether, our work defines a viral metabolic reprogramming mechanism underpinning KSHV oncogenesis, which may spur the development of new strategies to treat KSHV-associated malignancies and other diseases.
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Affiliation(s)
- Quanyuan Wan
- Florida Research and Innovation Center, Cleveland Clinic, Port St. Lucie, FL, USA
| | - Leah Tavakoli
- Florida Research and Innovation Center, Cleveland Clinic, Port St. Lucie, FL, USA
| | - Ting-Yu Wang
- Section of Infection and Immunity, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA, USA
- Proteome Exploration Laboratory, Beckman Institute, California Institute of Technology, Pasadena, CA, USA
| | - Andrew J Tucker
- Florida Research and Innovation Center, Cleveland Clinic, Port St. Lucie, FL, USA
| | - Ruiting Zhou
- Florida Research and Innovation Center, Cleveland Clinic, Port St. Lucie, FL, USA
| | - Qizhi Liu
- Section of Infection and Immunity, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA, USA
- State Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal University, Changsha, Hunan, China
| | - Shu Feng
- Section of Infection and Immunity, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA, USA
- Department of Diabetes & Cancer Metabolism, Beckman Research Institute of City of Hope, Duarte, CA, USA
| | - Dongwon Choi
- Department of Surgery, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Zhiheng He
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Michaela U Gack
- Florida Research and Innovation Center, Cleveland Clinic, Port St. Lucie, FL, USA
| | - Jun Zhao
- Florida Research and Innovation Center, Cleveland Clinic, Port St. Lucie, FL, USA.
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Wang S, Tian X, Zhou Y, Xie J, Gao M, Zhong Y, Zhang C, Yu K, Bai L, Qin Q, Zhong B, Lin D, Feng P, Lan K, Zhang J. Non-canonical regulation of the reactivation of an oncogenic herpesvirus by the OTUD4-USP7 deubiquitinases. PLoS Pathog 2024; 20:e1011943. [PMID: 38215174 PMCID: PMC10810452 DOI: 10.1371/journal.ppat.1011943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 01/25/2024] [Accepted: 01/03/2024] [Indexed: 01/14/2024] Open
Abstract
Deubiquitinases (DUBs) remove ubiquitin from substrates and play crucial roles in diverse biological processes. However, our understanding of deubiquitination in viral replication remains limited. Employing an oncogenic human herpesvirus Kaposi's sarcoma-associated herpesvirus (KSHV) to probe the role of protein deubiquitination, we found that Ovarian tumor family deubiquitinase 4 (OTUD4) promotes KSHV reactivation. OTUD4 interacts with the replication and transcription activator (K-RTA), a key transcription factor that controls KSHV reactivation, and enhances K-RTA stability by promoting its deubiquitination. Notably, the DUB activity of OTUD4 is not required for K-RTA stabilization; instead, OTUD4 functions as an adaptor protein to recruit another DUB, USP7, to deubiquitinate K-RTA and facilitate KSHV lytic reactivation. Our study has revealed a novel mechanism whereby KSHV hijacks OTUD4-USP7 deubiquitinases to promote lytic reactivation, which could be potentially harnessed for the development of new antiviral therapies.
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Affiliation(s)
- Shaowei Wang
- State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, Key Laboratory of Oral Biomedicine Ministry of Education, Hubei Key Laboratory of Stomatology, School & Hospital of Stomatology, State Key Laboratory of Virology, Medical Research Institute, Wuhan University, Wuhan, China
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, China
- Hubei Key Laboratory of Tumor Biological Behaviors, Hubei Province Cancer Clinical Study Center, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Xuezhang Tian
- State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, Key Laboratory of Oral Biomedicine Ministry of Education, Hubei Key Laboratory of Stomatology, School & Hospital of Stomatology, State Key Laboratory of Virology, Medical Research Institute, Wuhan University, Wuhan, China
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, China
| | - Yaru Zhou
- State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, Key Laboratory of Oral Biomedicine Ministry of Education, Hubei Key Laboratory of Stomatology, School & Hospital of Stomatology, State Key Laboratory of Virology, Medical Research Institute, Wuhan University, Wuhan, China
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, China
| | - Jun Xie
- State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, Key Laboratory of Oral Biomedicine Ministry of Education, Hubei Key Laboratory of Stomatology, School & Hospital of Stomatology, State Key Laboratory of Virology, Medical Research Institute, Wuhan University, Wuhan, China
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, China
| | - Ming Gao
- State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, Key Laboratory of Oral Biomedicine Ministry of Education, Hubei Key Laboratory of Stomatology, School & Hospital of Stomatology, State Key Laboratory of Virology, Medical Research Institute, Wuhan University, Wuhan, China
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, China
| | - Yunhong Zhong
- State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, Key Laboratory of Oral Biomedicine Ministry of Education, Hubei Key Laboratory of Stomatology, School & Hospital of Stomatology, State Key Laboratory of Virology, Medical Research Institute, Wuhan University, Wuhan, China
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, China
| | - Chuchu Zhang
- State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, Key Laboratory of Oral Biomedicine Ministry of Education, Hubei Key Laboratory of Stomatology, School & Hospital of Stomatology, State Key Laboratory of Virology, Medical Research Institute, Wuhan University, Wuhan, China
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, China
| | - Keying Yu
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, China
- Department of Gastrointestinal Surgery, Medical Research Institute, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, China
| | - Lei Bai
- State Key Laboratory of Virology, School of Life Sciences, Wuhan University, Wuhan, China
| | - Qingsong Qin
- Laboratory of Human Virology and Oncology, Shantou University Medical College, Shantou, China
| | - Bo Zhong
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, China
- Department of Gastrointestinal Surgery, Medical Research Institute, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, China
| | - Dandan Lin
- Cancer Center, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China
| | - Pinghui Feng
- Section of Infection and Immunity, Herman Ostrow School of Dentistry, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, California, United States of America
| | - Ke Lan
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, China
- State Key Laboratory of Virology, School of Life Sciences, Wuhan University, Wuhan, China
| | - Junjie Zhang
- State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, Key Laboratory of Oral Biomedicine Ministry of Education, Hubei Key Laboratory of Stomatology, School & Hospital of Stomatology, State Key Laboratory of Virology, Medical Research Institute, Wuhan University, Wuhan, China
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, China
- Hubei Key Laboratory of Tumor Biological Behaviors, Hubei Province Cancer Clinical Study Center, Zhongnan Hospital of Wuhan University, Wuhan, China
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Studstill CJ, Mac M, Moody CA. Interplay between the DNA damage response and the life cycle of DNA tumor viruses. Tumour Virus Res 2023; 16:200272. [PMID: 37918513 PMCID: PMC10685005 DOI: 10.1016/j.tvr.2023.200272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 10/26/2023] [Accepted: 10/29/2023] [Indexed: 11/04/2023] Open
Abstract
Approximately 20 % of human cancers are associated with virus infection. DNA tumor viruses can induce tumor formation in host cells by disrupting the cell's DNA replication and repair mechanisms. Specifically, these viruses interfere with the host cell's DNA damage response (DDR), which is a complex network of signaling pathways that is essential for maintaining the integrity of the genome. DNA tumor viruses can disrupt these pathways by expressing oncoproteins that mimic or inhibit various DDR components, thereby promoting genomic instability and tumorigenesis. Recent studies have highlighted the molecular mechanisms by which DNA tumor viruses interact with DDR components, as well as the ways in which these interactions contribute to viral replication and tumorigenesis. Understanding the interplay between DNA tumor viruses and the DDR pathway is critical for developing effective strategies to prevent and treat virally associated cancers. In this review, we discuss the current state of knowledge regarding the mechanisms by which human papillomavirus (HPV), merkel cell polyomavirus (MCPyV), Kaposi's sarcoma-associated herpesvirus (KSHV), and Epstein-Barr virus (EBV) interfere with DDR pathways to facilitate their respective life cycles, and the consequences of such interference on genomic stability and cancer development.
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Affiliation(s)
- Caleb J Studstill
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, United States
| | - Michelle Mac
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, United States
| | - Cary A Moody
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, United States; Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, United States.
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Li Y, Xu H, Tan X, Cui Q, Gu W, Pan Z, Yang L, Wu S, Wang X, Li D. Parthenolide inhibits proliferation of cells infected with Kaposi's sarcoma-associated herpesvirus by suppression of the NF-κB signaling pathway. Arch Virol 2023; 168:39. [PMID: 36609933 DOI: 10.1007/s00705-022-05626-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 10/19/2022] [Indexed: 01/09/2023]
Abstract
The disease caused by Kaposi's sarcoma-associated herpesvirus (KSHV) is one of the major causes of death of individuals with acquired immunodeficiency syndrome (AIDS). Development of anti-KSHV drugs is thus crucial. In this study, we investigated the effect of parthenolide (PTL) on the proliferation and NF-κB signaling pathway of KSHV-infected cells. iSLK.219 and KSHV-infected SH-SY5Y cells (SK-RG) were treated with PTL, TaqMan real-time quantitative PCR was used to determine the number of copies of the KSHV genome, and mRNA and protein expression of KSHV genes were analyzed by real-time PCR and immunocytochemistry. A cell viability test was used to measure cell proliferation, and flow cytometry was used to examine the effect of the drug on the cell cycle. Cyclin D1, CDK6, CDK4, and NF-κB-related proteins, including IKKβ, P-p65, and P-IKB-α, were detected by Western blot. The results showed that PTL altered the morphology of the cells, reduced the KSHV copy number, and suppressed the production of ORF50, K8.1, and v-GPCR mRNA and the LANA, ORF50, and K8.1 proteins. It blocked the G1 phase in iSLK.219 cells and decreased the levels of cyclin D1, CDK6, and CDK4 as well as the levels of NF-κB signaling proteins, including IKKβ, P-p65, and P-IKB-α. Together, these results suggest that PTL is a candidate drug that can decrease KSHV pathogenicity by suppressing cell proliferation and inhibiting the NF-κB signaling pathway in KSHV-infected cells.
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Affiliation(s)
- Ying Li
- Key Laboratory of Xinjiang Endemic and Ethnic Diseases/NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, Shihezi University, Shihezi, 832002, Xinjiang, China
- School of Medicine, Tarim University, Alaer, 843300, Xinjiang, China
| | - Huiling Xu
- Key Laboratory of Xinjiang Endemic and Ethnic Diseases/NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, Shihezi University, Shihezi, 832002, Xinjiang, China
| | - Xiaohua Tan
- School of Medicine, Hangzhou Normal University, Hangzhou, 310036, Zhejiang, China
| | - Qinghua Cui
- Department of Biomedical Informatics, School of Basic Medical Sciences, Peking University, 38 Xueyuan Rd, Beijing, 100191, China
| | - Wenyi Gu
- Australian Institute for Bioengineering and Nanotechnology (AIBN), University of Queensland (UQ), Corner College and Cooper Roads (Building 75), St Lucia, Brisbane, QLD, 4072, Australia
| | - Zemin Pan
- Key Laboratory of Xinjiang Endemic and Ethnic Diseases/NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, Shihezi University, Shihezi, 832002, Xinjiang, China
| | - Lei Yang
- School of Medicine, Hangzhou Normal University, Hangzhou, 310036, Zhejiang, China
| | - Shuyuan Wu
- Key Laboratory of Xinjiang Endemic and Ethnic Diseases/NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, Shihezi University, Shihezi, 832002, Xinjiang, China
| | - Xiaolu Wang
- Key Laboratory of Xinjiang Endemic and Ethnic Diseases/NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, Shihezi University, Shihezi, 832002, Xinjiang, China
| | - Dongmei Li
- Key Laboratory of Xinjiang Endemic and Ethnic Diseases/NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, Shihezi University, Shihezi, 832002, Xinjiang, China.
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Lymphotropic Viruses: Chronic Inflammation and Induction of Cancers. BIOLOGY 2020; 9:biology9110390. [PMID: 33182552 PMCID: PMC7697807 DOI: 10.3390/biology9110390] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 11/04/2020] [Accepted: 11/06/2020] [Indexed: 12/18/2022]
Abstract
Inflammation induced by transcription factors, including Signal Transducers and Activators of Transcription (STATs) and NF-κB, in response to microbial pathogenic infections and ligand dependent receptors stimulation are critical for controlling infections. However, uncontrolled inflammation induced by these transcription factors could lead to immune dysfunction, persistent infection, inflammatory related diseases and the development of cancers. Although the induction of innate immunity and inflammation in response to viral infection is important to control virus replication, its effects can be modulated by lymphotropic viruses including human T-cell leukemia virus type 1 (HTLV-1), Κaposi's sarcoma herpesvirus (KSHV), and Epstein Barr virus (EBV) during de novo infection as well as latent infection. These lymphotropic viruses persistently activate JAK-STAT and NF-κB pathways. Long-term STAT and NF-κB activation by these viruses leads to the induction of chronic inflammation, which can support the persistence of these viruses and promote virus-mediated cancers. Here, we review how HTLV-1, KSHV and EBV hijack the function of host cell surface molecules (CSMs), which are involved in the regulation of chronic inflammation, innate and adaptive immune responses, cell death and the restoration of tissue homeostasis. Thus, better understanding of CSMs-mediated chronic activation of STATs and NF-κB pathways in lymphotropic virus-infected cells may pave the way for therapeutic intervention in malignancies caused by lymphotropic viruses.
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6
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Regulation of KSHV Latency and Lytic Reactivation. Viruses 2020; 12:v12091034. [PMID: 32957532 PMCID: PMC7551196 DOI: 10.3390/v12091034] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 09/10/2020] [Accepted: 09/12/2020] [Indexed: 02/06/2023] Open
Abstract
Kaposi’s sarcoma-associated herpesvirus (KSHV) is associated with three malignancies— Kaposi’s sarcoma (KS), primary effusion lymphoma (PEL), and multicentric Castleman’s disease (MCD). Central to the pathogenesis of these diseases is the KSHV viral life cycle, which is composed of a quiescent latent phase and a replicative lytic phase. While the establishment of latency enables persistent KSHV infection and evasion of the host immune system, lytic replication is essential for the dissemination of the virus between hosts and within the host itself. The transition between these phases, known as lytic reactivation, is controlled by a complex set of environmental, host, and viral factors. The effects of these various factors converge on the regulation of two KSHV proteins whose functions facilitate each phase of the viral life cycle—latency-associated nuclear antigen (LANA) and the master switch of KSHV reactivation, replication and transcription activator (RTA). This review presents the current understanding of how the transition between the phases of the KSHV life cycle is regulated, how the various phases contribute to KSHV pathogenesis, and how the viral life cycle can be exploited as a therapeutic target.
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Priyathilaka TT, Bathige SDNK, Lee S, Yang H, Jeong T, Lee S, Lee J. Structural and functional analysis of three Iκb kinases (IKK) in disk abalone (Haliotis discus discus): Investigating their role in the innate immune responses. FISH & SHELLFISH IMMUNOLOGY 2020; 103:111-125. [PMID: 32320761 DOI: 10.1016/j.fsi.2020.04.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Revised: 04/11/2020] [Accepted: 04/14/2020] [Indexed: 06/11/2023]
Abstract
The IκB kinases (IKK) are large multiprotein complexes that regulate the activation of the transcription factor NF-κB and are involved in a diverse range of biological processes, including innate immunity, inflammation, and development. To explore the potential roles of invertebrate IKKs on immunity, three IKK encoding genes have been identified from molluscan species disk abalone and designed as AbIKK1, AbIKK2 and AbIKK3 at the transcriptional level. Coding sequences of AbIKK1, AbIKK2 and AbIKK3 encode the peptides of 746, 751 and 713 amino acids with the predicted molecular mass of 86.16, 86.12 and 81.88 kDa respectively. All three AbIKKs were found to share conserved IKK family features including the kinase superfamily domain (KD), ubiquitin-like domain (ULD), and α-helical scaffold/dimerization domain (SDD), similar to their mammalian counterparts. Under normal physiological conditions, AbIKKs were ubiquitously detected in six different tissues, with the highest abundance in the digestive tract and gills. Temporal transcriptional profiles in abalone hemocytes revealed the induction of AbIKK1, AbIKK2, and AbIKK3 expression following exposure to Gram-negative (Vibrio parahemolyticus) and Gram-positive (Listeria monocytogenes) bacteria, viruses (viral hemorrhagic septicemia virus, VHSV), LPS, or poly I:C. The overexpression of AbIKKs in HEK293T or RAW264.7 murine macrophage cells induced NF-κB promoter activation independent of stimulation by TNF-α or LPS. Moreover, iNOS and COX2 expression was induced in AbIKK transfected RAW264.7 murine macrophage cells and the induced state was maintained post-LPS treatment. Furthermore, mRNA levels of three selected cytokine-encoding genes (IL-1β, IL-6, and TNF-α) were found to be elevated in abalone IKK overexpressed RAW264.7 murine macrophage cells, both with and without LPS exposure. Overall, our findings demonstrated that AbIKKs identified in this study were positively involved in eliciting innate immune responses in abalone. In addition, the data revealed the presence of an evolutionarily conserved signaling mechanism for IKK mediated NF-κB activation in mollusks.
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Affiliation(s)
| | - S D N K Bathige
- Sri Lanka Institute of Nanotechnology (SLINTEC), Nanotechnology and Science Park, Mahenwatta, Pitipana, Homagama, Sri Lanka
| | - Seongdo Lee
- Department of Marine Life Sciences & Fish Vaccine Research Center, Jeju National University, Jeju Self-Governing Province, 63243, Republic of Korea; Marine Science Institute, Jeju National University, Jeju Self-Governing Province, 63333, Republic of Korea
| | - Hyerim Yang
- Department of Marine Life Sciences & Fish Vaccine Research Center, Jeju National University, Jeju Self-Governing Province, 63243, Republic of Korea
| | - Taehyug Jeong
- Department of Marine Life Sciences & Fish Vaccine Research Center, Jeju National University, Jeju Self-Governing Province, 63243, Republic of Korea; Marine Science Institute, Jeju National University, Jeju Self-Governing Province, 63333, Republic of Korea
| | - Sukkyoung Lee
- Department of Marine Life Sciences & Fish Vaccine Research Center, Jeju National University, Jeju Self-Governing Province, 63243, Republic of Korea; Marine Science Institute, Jeju National University, Jeju Self-Governing Province, 63333, Republic of Korea
| | - Jehee Lee
- Department of Marine Life Sciences & Fish Vaccine Research Center, Jeju National University, Jeju Self-Governing Province, 63243, Republic of Korea; Marine Science Institute, Jeju National University, Jeju Self-Governing Province, 63333, Republic of Korea.
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Yang Z, Honda T, Ueda K. vFLIP upregulates IKKε, leading to spindle morphology formation through RelA activation. Virology 2018; 522:106-121. [PMID: 30029010 DOI: 10.1016/j.virol.2018.07.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 07/07/2018] [Accepted: 07/07/2018] [Indexed: 12/31/2022]
Abstract
Kaposi's sarcoma (KS)-associated herpesvirus (KSHV) vFLIP, a latent gene of KSHV, was first identified as a FLICE-inhibitory protein (FLIP) protecting cells from apoptosis. The vFLIP protein has been shown to activate the NF-κB signaling involved in spindle morphology formation both in HUVECs infected with KSHV and Kaposi's sarcoma (KS) itself. In this study, we independently established stably vFLIP-expressing cells and showed that they exhibited upregulated NF-κB family protein expression independent of the ability of IKKs to bind vFLIP. Further, vFLIP induced upregulation of IKKε, phosphorylation of RelA at Ser468 (p-RelA S468) and nuclear localization of Re1A concomitant with spindle morphology formation, and these effects were reversed by knockdown of IKKε and treatment with Bay-11. Overexpression of IKKε alone also showed spindle morphology formation with p-RelA S468. In conclusion, the spindle cell morphology in KS should be induced by RelA activation (p-RelA S468) by IKKε upregulation in vFLIP-expressing EA hy926 cells.
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Affiliation(s)
- Zunlin Yang
- Division of Virology, Department of Microbiology and Immunology, Osaka University Graduate School of Medicine, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Tomoyuki Honda
- Division of Virology, Department of Microbiology and Immunology, Osaka University Graduate School of Medicine, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Keiji Ueda
- Division of Virology, Department of Microbiology and Immunology, Osaka University Graduate School of Medicine, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan.
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Van Skike ND, Minkah NK, Hogan CH, Wu G, Benziger PT, Oldenburg DG, Kara M, Kim-Holzapfel DM, White DW, Tibbetts SA, French JB, Krug LT. Viral FGARAT ORF75A promotes early events in lytic infection and gammaherpesvirus pathogenesis in mice. PLoS Pathog 2018; 14:e1006843. [PMID: 29390024 PMCID: PMC5811070 DOI: 10.1371/journal.ppat.1006843] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 02/13/2018] [Accepted: 12/27/2017] [Indexed: 12/19/2022] Open
Abstract
Gammaherpesviruses encode proteins with homology to the cellular purine metabolic enzyme formyl-glycinamide-phosphoribosyl-amidotransferase (FGARAT), but the role of these viral FGARATs (vFGARATs) in the pathogenesis of a natural host has not been investigated. We report a novel role for the ORF75A vFGARAT of murine gammaherpesvirus 68 (MHV68) in infectious virion production and colonization of mice. MHV68 mutants with premature stop codons in orf75A exhibited a log reduction in acute replication in the lungs after intranasal infection, which preceded a defect in colonization of multiple host reservoirs including the mediastinal lymph nodes, peripheral blood mononuclear cells, and the spleen. Intraperitoneal infection rescued splenic latency, but not reactivation. The 75A.stop virus also exhibited defective replication in primary fibroblast and macrophage cells. Viruses produced in the absence of ORF75A were characterized by an increase in the ratio of particles to PFU. In the next round of infection this led to the alteration of early events in lytic replication including the deposition of the ORF75C tegument protein, the accelerated kinetics of viral gene expression, and induction of TNFα release and cell death. Infecting cells to deliver equivalent genomes revealed that ORF75A was required for initiating early events in infection. In contrast with the numerous phenotypes observed in the absence of ORF75A, ORF75B was dispensable for replication and pathogenesis. These studies reveal that murine rhadinovirus vFGARAT family members ORF75A and ORF75C have evolved to perform divergent functions that promote replication and colonization of the host. Gammaherpesviruses are infectious agents that cause cancer. The study of viral genes unique to this subfamily may offer insight into the strategies that these viruses use to persist in the host and drive disease. The vFGARATs are a family of viral proteins found only in gammaherpesviruses, and are critical for replication in cell culture. Here we report that a rhadinovirus of rodents requires a previously uncharacterized vFGARAT family member, ORF75A, to support viral growth and persistence in mice. In addition, viruses lacking ORF75A are defective in the production of infectious viral particles. Thus, duplications and functional divergence of the various vFGARATs in the rhadinovirus lineage have likely been driven by selective pressures to disseminate within and colonize the host. Identification of the shared host processes that are targeted by the diverse family of vFGARATs may reveal novel targets for therapeutic agents to prevent life-long infections by these oncogenic viruses.
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Affiliation(s)
- Nick D. Van Skike
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, United States of America
| | - Nana K. Minkah
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, United States of America
| | - Chad H. Hogan
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, United States of America
- Graduate Program of Genetics, Stony Brook University, Stony Brook, New York, United States of America
| | - Gary Wu
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, United States of America
| | - Peter T. Benziger
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, United States of America
| | | | - Mehmet Kara
- Department of Molecular Genetics and Microbiology and UF Shands Cancer Center, College of Medicine, University of Florida, Gainesville, Florida, United States of America
| | - Deborah M. Kim-Holzapfel
- Departments of Chemistry and of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, New York, United States of America
| | - Douglas W. White
- Gundersen Health System, La Crosse, Wisconsin, United States of America
| | - Scott A. Tibbetts
- Department of Molecular Genetics and Microbiology and UF Shands Cancer Center, College of Medicine, University of Florida, Gainesville, Florida, United States of America
| | - Jarrod B. French
- Departments of Chemistry and of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, New York, United States of America
| | - Laurie T. Krug
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, United States of America
- * E-mail:
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Chen M, Sun F, Han L, Qu Z. Kaposi's sarcoma herpesvirus (KSHV) microRNA K12-1 functions as an oncogene by activating NF-κB/IL-6/STAT3 signaling. Oncotarget 2017; 7:33363-73. [PMID: 27166260 PMCID: PMC5078101 DOI: 10.18632/oncotarget.9221] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 04/10/2016] [Indexed: 01/01/2023] Open
Abstract
The human oncogenic virus Kaposi's sarcoma herpesvirus (KSHV) is the most common cause of malignancies among AIDS patients. KSHV possesses over hundred genes, including 25 microRNAs (miRNAs). The roles of these miRNAs and many other viral genes in KSHV biology and pathogenesis remain largely unknown. Accordingly, the molecular mechanisms by which KSHV induces tumorigenesis are still poorly defined. Here, we identify KSHV miRNA K12-1 (miR-K12-1) as a novel viral oncogene by activating two important transcription factors, nuclear factor-κb (NF-κB) and signal transducer and activator of transcription 3 (STAT3). Interestingly, miR-K12-1 activates STAT3 indirectly through inducing NF-κB activation and NF-κB-dependent expression of the cytokine interleukin-6 (IL-6) by repressing the expression of the NF-κB inhibitor IκBα. Accordingly, expression of ectopic IκBα or knockdown of NF-κB RelA, IL-6 or STAT3 prevents expression of cell growth genes and suppresses the oncogenicities of both miR-K12-1 and KSHV. These data identify miR-K12-1/NF-κB/IL-6/STAT3 as a novel oncogenic signaling underlying KSHV tumorigenesis. These data also provide the first evidence showing that IL-6/STAT3 signaling acts as an essential mediator of NF-κB oncogenic actions. These findings significantly improve our understanding of KSHV pathogenesis and oncogenic interaction between NF-κB and STAT3.
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Affiliation(s)
- Mingqing Chen
- University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.,Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.,Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, Hubei, China
| | - Fan Sun
- University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.,Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Lei Han
- University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.,Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Zhaoxia Qu
- University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.,Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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11
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The regulatory role of protein phosphorylation in human gammaherpesvirus associated cancers. Virol Sin 2017; 32:357-368. [PMID: 29116588 PMCID: PMC6704201 DOI: 10.1007/s12250-017-4081-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Accepted: 10/23/2017] [Indexed: 12/12/2022] Open
Abstract
Activation of specific sets of protein kinases by intracellular signal molecules
has become more and more apparent in the past decade. Phosphorylation, one of key
posttranslational modification events, is activated by kinase or regulatory protein
and is vital for controlling many physiological functions of eukaryotic cells such
as cell proliferation, differentiation, malignant transformation, and signal
transduction mediated by external stimuli. Moreovers, the reversible modification of
phosphorylation and dephosphorylation can result in different features of the target
substrate molecules including DNA binding, protein-protein interaction, subcellular
location and enzymatic activity, and is often hijacked by viral infection.
Epstein-Barr virus (EBV) and Kaposi’s sarcomaassociated herpesvirus (KSHV), two
human oncogenic gamma-herpesviruses, are shown to tightly associate with many
malignancies. In this review, we summarize the recent progresses on understanding of
molecular properties and regulatory modes of cellular and viral proteins
phosphorylation influenced by these two tumor viruses, and highlight the potential
therapeutic targets and strategies against their related cancers. ![]()
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12
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Chen J, Zhao J, Chen X, Ding C, Lee K, Jia Z, Zhang Y, Zhou Y, Wei C, He J, Xia Z, Peng J. Hyper activation of β-catenin signalling induced by IKKε inhibition thwarts colorectal cancer cell proliferation. Cell Prolif 2017; 50. [PMID: 28523736 DOI: 10.1111/cpr.12350] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 03/30/2017] [Indexed: 12/22/2022] Open
Abstract
OBJECTIVE Aberrant activation of Wnt/β-catenin signalling contributes significantly to the development of human colorectal cancers and β-catenin is the key signalling molecule transducing canonical Wnt/β-catenin signalling. Therefore, β-catenin is a promising therapeutic target for cancer treatment. This study demonstrates that the oncogenic IKKε kinase phosphorylates β-catenin to restrain its hyper activation, therefore promoting colorectal cancer (CRC) cell proliferation. MATERIALS AND METHODS IKKε and β-catenin expression levels in human colorectal cancer tissues and cell lines were analysed by immunohistochemical staining and Western blotting. The regulation of IKKε on Wnt/β-catenin signalling pathway was studied by reporter assay and real-time PCR analysis in the context of IKKε stably knocking down. Co-immunoprecipitation was conducted to monitor the interaction between IKKε and β-catenin. Kinase assay was performed to measure β-catenin post-translational modifications induced by IKKε. RESULTS Oncogenic IKKε kinase is required for the proliferation of colorectal cancer cells. Mechanistically, inhibition of IKKε results in β-catenin hyper activation and thwarts CRC cell proliferation. Furthermore, IKKε phosphorylates β-catenin and inhibits the activation of β-catenin signalling. CONCLUSION Our study suggests that IKKε is a potential target to combat CRC induced by aberrant Wnt/β-catenin signalling.
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Affiliation(s)
- Jie Chen
- Division of General Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China.,Department of Molecular Microbiology and Immunology, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA, 90033, USA
| | - Jun Zhao
- Department of Molecular Microbiology and Immunology, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA, 90033, USA
| | - Xuan Chen
- Division of General Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China
| | - Chengming Ding
- Division of General Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China
| | - Katie Lee
- Department of Molecular Microbiology and Immunology, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA, 90033, USA
| | - Zeming Jia
- Division of General Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China
| | - Yaoting Zhang
- Division of General Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China
| | - Yuzheng Zhou
- State Key Laboratory of Medical Genetics and School of Life Sciences, Central South University, Changsha, Hunan, 410008, China
| | - Chaoying Wei
- State Key Laboratory of Medical Genetics and School of Life Sciences, Central South University, Changsha, Hunan, 410008, China
| | - Jiantai He
- Division of General Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China
| | - Zanxian Xia
- State Key Laboratory of Medical Genetics and School of Life Sciences, Central South University, Changsha, Hunan, 410008, China
| | - Jian Peng
- Division of General Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China
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13
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O. Temajo N, Howard N. The divergence between the virus and cellular oxidative stress as separate environmental agents that trigger autoimmunity originates from their different procedural mechanisms of activating the same molecular entity: the transcription factor NF-kappa B. AIMS ALLERGY AND IMMUNOLOGY 2017. [DOI: 10.3934/allergy.2017.2.50] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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14
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Zhang X, Yu H, Zhao J, Li X, Li J, He J, Xia Z, Zhao J. IKKϵ negatively regulates RIG-I via direct phosphorylation. J Med Virol 2016; 88:712-8. [PMID: 26354181 DOI: 10.1002/jmv.24376] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/06/2015] [Indexed: 02/01/2023]
Abstract
Inhibitor of nuclear factor kappa-B kinase Epsilon (IKKϵ) is an IKK-related kinase. Despite it was originally discovered as a kinase functionally related to TBK-1, studies entailing gene knockout mouse demonstrated that IKKϵ is dispensable for interferon induction by viral infection. In this study, we report that IKKϵ directly phosphorylates a key serine residue within the RNA-binding domain of RIG-I (retinoic acid-inducible gene 1) to inhibit RIG-I-mediate innate immune signaling. Using IKKϵ-deficient MEFs, we found that loss of IKKϵ resulted in increased cytokine production in response to the activation of cytosolic sensors. Biochemical analyses indicated that IKKϵ physically associated with and phosphorylated RIG-I. Mass spectrometry analysis identified that IKKϵ phosphorylated the serine 855 of the RNA-binding pocket of RIG-I carboxyl terminal domain, a residues known to impinge on RNA-binding via phosphorylation. Our findings collectively support the conclusion that IKKϵ modulates innate immune signaling cascades via phosphorylating the RIG-I cytosolic sensor, providing a feedback regulatory mechanism.
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Affiliation(s)
- Xiaoqing Zhang
- Xiangya Hospital, Central South University, Changsha, Hunan, P. R. China
- Department of Molecular Microbiology and Immunology, University of Southern California, Los Angeles, California
| | - Haiyang Yu
- Xiangya Hospital, Central South University, Changsha, Hunan, P. R. China
| | - Jun Zhao
- Department of Molecular Microbiology and Immunology, University of Southern California, Los Angeles, California
| | - Xiuqing Li
- Department of Medicine, University of Southern California, Los Angeles, California
| | - Jiada Li
- State Key Laboratory of Medical Genetics & School of Life Sciences, Central South University, Changsha, Hunan, P. R. China
| | - Jiantai He
- Xiangya Hospital, Central South University, Changsha, Hunan, P. R. China
| | - Zanxian Xia
- State Key Laboratory of Medical Genetics & School of Life Sciences, Central South University, Changsha, Hunan, P. R. China
| | - Jinfeng Zhao
- Xiangya Hospital, Central South University, Changsha, Hunan, P. R. China
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15
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Sun F, Xiao Y, Qu Z. Oncovirus Kaposi sarcoma herpesvirus (KSHV) represses tumor suppressor PDLIM2 to persistently activate nuclear factor κB (NF-κB) and STAT3 transcription factors for tumorigenesis and tumor maintenance. J Biol Chem 2015; 290:7362-8. [PMID: 25681443 DOI: 10.1074/jbc.c115.637918] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Kaposi sarcoma herpesvirus (KSHV) is the most common cause of malignancies among AIDS patients. However, how KSHV induces tumorigenesis remains largely unknown. Here, we demonstrate that one important mechanism underlying the tumorigenesis of KSHV is through transcriptional repression of the tumor suppressor gene PDZ-LIM domain-containing protein 2 (PDLIM2). PDLIM2 expression is repressed in KSHV-transformed human umbilical vascular endothelial cells as well as in KSHV-associated cancer cell lines and primary tumors. Importantly, PDLIM2 repression is essential for KSHV-induced persistent activation of nuclear factor κB (NF-κB) and signal transducer and activator of transcription 3 (STAT3) and subsequent tumorigenesis and tumor maintenance. Our mechanistic studies indicate that PDLIM2 repression by KSHV involves DNA methylation. Notably, the epigenetic repression of PDLIM2 can be reversed by 5-aza-2-deoxycytidine and vitamin D to suppress KSHV-associated cancer cell growth. These studies not only improve our understanding of KSHV pathogenesis but also provide immediate therapeutic strategies for KSHV-mediated cancers, particularly those associated with AIDS.
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Affiliation(s)
- Fan Sun
- From the University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232, and the Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
| | - Yadong Xiao
- From the University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232, and
| | - Zhaoxia Qu
- From the University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232, and the Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
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16
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Amaya M, Keck F, Bailey C, Narayanan A. The role of the IKK complex in viral infections. Pathog Dis 2014; 72:32-44. [PMID: 25082354 PMCID: PMC7108545 DOI: 10.1111/2049-632x.12210] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Revised: 06/11/2014] [Accepted: 07/17/2014] [Indexed: 01/21/2023] Open
Abstract
The NF‐κB signal transduction pathway is a critical regulator of multiple cellular functions that ultimately shift the balance between cell survival and death. The cascade is activated by many intrinsic and extrinsic stimuli, which is transduced via adaptor proteins to phosphorylate the IκB kinase (IKK) complex, which in turn phosphorylates the inhibitory IκBα protein to undergo proteasomal degradation and sets in motion nuclear events in response to the initial stimulus. Viruses are important modulators of the NF‐κB cascade and have evolved multiple mechanisms to activate or inhibit this pathway in a manner conducive to viral multiplication and establishment of a productive infectious cycle. This is a subject of extensive research by multiple laboratories whereby unraveling the interactions between specific viral components and members of the NF‐κB signal transduction cascade can shed unique perspectives on infection associated pathogenesis and novel therapeutic targets. In this review, we highlight the interactions between components of the IKK complex and multiple RNA and DNA viruses with the emphasis on mechanisms by which the interaction feeds the infection. Understanding these interactions will shed light on the exploitative capabilities of viruses to maintain an environment favorable for a productive infection.
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Affiliation(s)
- Moushimi Amaya
- National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, Manassas, VA, USA
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17
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Interplay between Kaposi's sarcoma-associated herpesvirus and the innate immune system. Cytokine Growth Factor Rev 2014; 25:597-609. [PMID: 25037686 DOI: 10.1016/j.cytogfr.2014.06.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 06/16/2014] [Indexed: 02/04/2023]
Abstract
Understanding of the innate immune response to viral infections is rapidly progressing, especially with regards to the detection of DNA viruses. Kaposi's sarcoma-associated herpesvirus (KSHV) is a large dsDNA virus that is responsible for three human diseases: Kaposi's sarcoma, primary effusion lymphoma and multicentric Castleman's disease. The major target cells of KSHV (B cells and endothelial cells) express a wide range of pattern recognition receptors (PRRs) and play a central role in mobilizing inflammatory responses. On the other hand, KSHV encodes an array of immune evasion genes, including several pirated host genes, which interfere with multiple aspects of the immune response. This review summarizes current understanding of innate immune recognition of KSHV and the role of immune evasion genes that shape the antiviral and inflammatory responses.
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