1
|
Wongchitrat P, Chanmee T, Govitrapong P. Molecular Mechanisms Associated with Neurodegeneration of Neurotropic Viral Infection. Mol Neurobiol 2024; 61:2881-2903. [PMID: 37946006 PMCID: PMC11043213 DOI: 10.1007/s12035-023-03761-6] [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: 08/25/2022] [Accepted: 10/31/2023] [Indexed: 11/12/2023]
Abstract
Viral infections of the central nervous system (CNS) cause variable outcomes from acute to severe neurological sequelae with increased morbidity and mortality. Viral neuroinvasion directly or indirectly induces encephalitis via dysregulation of the immune response and contributes to the alteration of neuronal function and the degeneration of neuronal cells. This review provides an overview of the cellular and molecular mechanisms of virus-induced neurodegeneration. Neurotropic viral infections influence many aspects of neuronal dysfunction, including promoting chronic inflammation, inducing cellular oxidative stress, impairing mitophagy, encountering mitochondrial dynamics, enhancing metabolic rewiring, altering neurotransmitter systems, and inducing misfolded and aggregated pathological proteins associated with neurodegenerative diseases. These pathogenetic mechanisms create a multidimensional injury of the brain that leads to specific neuronal and brain dysfunction. The understanding of the molecular mechanisms underlying the neurophathogenesis associated with neurodegeneration of viral infection may emphasize the strategies for prevention, protection, and treatment of virus infection of the CNS.
Collapse
Affiliation(s)
- Prapimpun Wongchitrat
- Center for Research Innovation and Biomedical Informatics, Faculty of Medical Technology, Mahidol University, 999 Phutthamonthon 4 Road, Salaya, Phutthamonthon, Nakhon Pathom, 73170, Thailand.
| | - Theerawut Chanmee
- Department of Clinical Chemistry, Faculty of Medical Technology, Mahidol University, Salaya, Nakhon Pathom, Thailand
| | | |
Collapse
|
2
|
Pan Y, Cai W, Cheng A, Wang M, Huang J, Chen S, Yang Q, Wu Y, Sun D, Mao S, Zhu D, Liu M, Zhao X, Zhang S, Gao Q, Ou X, Tian B, Yin Z, Jia R. Duck Tembusu virus NS3 protein induces apoptosis by activating the PERK/PKR pathway and mitochondrial pathway. J Virol 2023; 97:e0149723. [PMID: 37877719 PMCID: PMC10688375 DOI: 10.1128/jvi.01497-23] [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: 09/24/2023] [Accepted: 09/25/2023] [Indexed: 10/26/2023] Open
Abstract
IMPORTANCE Duck Tembusu virus (DTMUV) is an emerging pathogenic flavivirus that replicates well in mosquito, bird, and mammalian cells. An in vivo study revealed that BALB/c mice and Kunming mice were susceptible to DTMUV after intracerebral inoculation. Moreover, there are no reports about DTMUV-related human disease, but antibodies against DTMUV and viral RNA were detected in the serum samples of duck industry workers. This information implies that DTMUV has expanded its host range and poses a threat to mammalian health. Thus, understanding the pathogenic mechanism of DTMUV is crucial for identifying potential antiviral targets. In this study, we discovered that NS3 can induce the mitochondria-mediated apoptotic pathway through the PERK/PKR pathway; it can also interact with voltage-dependent anion channel 2 to induce apoptosis. Our findings provide a theoretical basis for understanding the pathogenic mechanism of DTMUV infection and identifying potential antiviral targets and may also serve as a reference for exploring the pathogenesis of other flaviviruses.
Collapse
Affiliation(s)
- Yuhong Pan
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
| | - Wenjun Cai
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
| | - Anchun Cheng
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
| | - Mingshu Wang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
| | - Juan Huang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
| | - Shun Chen
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
| | - Qiao Yang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
| | - Ying Wu
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
| | - Di Sun
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
| | - Sai Mao
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
| | - Dekang Zhu
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
| | - Mafeng Liu
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
| | - Xinxin Zhao
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
| | - Shaqiu Zhang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
| | - Qun Gao
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
| | - Xumin Ou
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
| | - Bin Tian
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
| | - Zhongqiong Yin
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
| | - Renyong Jia
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
| |
Collapse
|
3
|
Jain S, Vimal N, Angmo N, Sengupta M, Thangaraj S. Dengue Vaccination: Towards a New Dawn of Curbing Dengue Infection. Immunol Invest 2023; 52:1096-1149. [PMID: 37962036 DOI: 10.1080/08820139.2023.2280698] [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] [Indexed: 11/15/2023]
Abstract
Dengue is an infectious disease caused by dengue virus (DENV) and is a serious global burden. Antibody-dependent enhancement and the ability of DENV to infect immune cells, along with other factors, lead to fatal Dengue Haemorrhagic Fever and Dengue Shock Syndrome. This necessitates the development of a robust and efficient vaccine but vaccine development faces a number of hurdles. In this review, we look at the epidemiology, genome structure and cellular targets of DENV and elaborate upon the immune responses generated by human immune system against DENV infection. The review further sheds light on various challenges in development of a potent vaccine against DENV which is followed by presenting a current account of different vaccines which are being developed or have been licensed.
Collapse
Affiliation(s)
- Sidhant Jain
- Independent Researcher, Institute for Globally Distributed Open Research and Education (IGDORE), Rewari, India
| | - Neha Vimal
- Bhaskaracharya College of Applied Sciences, University of Delhi, Delhi, India
| | - Nilza Angmo
- Maitreyi College, University of Delhi, Delhi, India
| | - Madhumita Sengupta
- Janki Devi Bajaj Government Girls College, University of Kota, Kota, India
| | - Suraj Thangaraj
- Swami Ramanand Teerth Rural Government Medical College, Maharashtra University of Health Sciences, Ambajogai, India
| |
Collapse
|
4
|
Nazneen F, Thompson EA, Blackwell C, Bai JS, Huang F, Bai F. An effective live-attenuated Zika vaccine candidate with a modified 5' untranslated region. NPJ Vaccines 2023; 8:50. [PMID: 37005424 PMCID: PMC10066991 DOI: 10.1038/s41541-023-00650-w] [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: 08/15/2022] [Accepted: 03/17/2023] [Indexed: 04/04/2023] Open
Abstract
Zika virus (ZIKV) is a mosquito-transmitted flavivirus that has caused devastating congenital Zika syndrome (CZS), including microcephaly, congenital malformation, and fetal demise in human newborns in recent epidemics. ZIKV infection can also cause Guillain-Barré syndrome (GBS) and meningoencephalitis in adults. Despite intensive research in recent years, there are no approved vaccines or antiviral therapeutics against CZS and adult Zika diseases. In this report, we developed a novel live-attenuated ZIKV strain (named Z7) by inserting 50 RNA nucleotides (nt) into the 5' untranslated region (UTR) of a pre-epidemic ZIKV Cambodian strain, FSS13025. We used this particular ZIKV strain as it is attenuated in neurovirulence, immune antagonism, and mosquito infectivity compared with the American epidemic isolates. Our data demonstrate that Z7 replicates efficiently and produces high titers without causing apparent cytopathic effects (CPE) in Vero cells or losing the insert sequence, even after ten passages. Significantly, Z7 induces robust humoral and cellular immune responses that completely prevent viremia after a challenge with a high dose of an American epidemic ZIKV strain PRVABC59 infection in type I interferon (IFN) receptor A deficient (Ifnar1-/-) mice. Moreover, adoptive transfer of plasma collected from Z7 immunized mice protects Ifnar1-/- mice from ZIKV (strain PRVABC59) infection. These results suggest that modifying the ZIKV 5' UTR is a novel strategy to develop live-attenuated vaccine candidates for ZIKV and potentially for other flaviviruses.
Collapse
Affiliation(s)
- Farzana Nazneen
- Cell and Molecular Biology Program, Center for Molecular and Cellular Biosciences, The University of Southern Mississippi, Hattiesburg, MS, 39406, USA
| | - E Ashley Thompson
- Cell and Molecular Biology Program, Center for Molecular and Cellular Biosciences, The University of Southern Mississippi, Hattiesburg, MS, 39406, USA
| | - Claire Blackwell
- Cell and Molecular Biology Program, Center for Molecular and Cellular Biosciences, The University of Southern Mississippi, Hattiesburg, MS, 39406, USA
| | - Jonathan S Bai
- Department of Chemistry and Biochemistry, University of Texas at Dallas, Richardson, TX, 75080, USA
| | - Faqing Huang
- Chemistry and Biochemistry Program, Center for Molecular and Cellular Biosciences, The University of Southern Mississippi, Hattiesburg, MS, 39406, USA
| | - Fengwei Bai
- Cell and Molecular Biology Program, Center for Molecular and Cellular Biosciences, The University of Southern Mississippi, Hattiesburg, MS, 39406, USA.
| |
Collapse
|
5
|
Karim SU, Bai F. Introduction to West Nile Virus. Methods Mol Biol 2023; 2585:1-7. [PMID: 36331759 DOI: 10.1007/978-1-0716-2760-0_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
West Nile virus (WNV) is a mosquito-borne, single-stranded, positive-sense RNA virus belonging to the Flaviviridae family. After WNV gains entry through an infected mosquito bite, it replicates in a variety of human cell types and produces a viremia. Although the majority of infected individuals remain asymptomatic, the manifested symptoms in some people range from a mild fever to severe neurological disorder with high morbidity and mortality. In addition, many who recover from WNV neuroinvasive infection present with long-term deficits, including weakness, fatigue, and cognitive problems. Since entering the USA in 1999, WNV has become the most common mosquito-borne virus in North America. Despite the intensive research over 20 years, there are still no approved vaccines or specific treatments for humans, and it remains an urgent need to understand the pathogenesis of WNV and develop specific therapeutics and vaccines.
Collapse
Affiliation(s)
- Shazeed-Ul Karim
- Department of Cell and Molecular Biology, Center for Molecular and Cellular Biosciences, The University of Southern Mississippi, Hattiesburg, MS, USA
| | - Fengwei Bai
- Department of Cell and Molecular Biology, Center for Molecular and Cellular Biosciences, The University of Southern Mississippi, Hattiesburg, MS, USA.
| |
Collapse
|
6
|
Pan Y, Cai W, Cheng A, Wang M, Yin Z, Jia R. Flaviviruses: Innate Immunity, Inflammasome Activation, Inflammatory Cell Death, and Cytokines. Front Immunol 2022; 13:829433. [PMID: 35154151 PMCID: PMC8835115 DOI: 10.3389/fimmu.2022.829433] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Accepted: 01/10/2022] [Indexed: 12/12/2022] Open
Abstract
The innate immune system is the host’s first line of defense against the invasion of pathogens including flavivirus. The programmed cell death controlled by genes plays an irreplaceable role in resisting pathogen invasion and preventing pathogen infection. However, the inflammatory cell death, which can trigger the overflow of a large number of pro-inflammatory cytokines and cell contents, will initiate a severe inflammatory response. In this review, we summarized the current understanding of the innate immune response, inflammatory cell death pathway and cytokine secretion regulation during Dengue virus, West Nile virus, Zika virus, Japanese encephalitis virus and other flavivirus infections. We also discussed the impact of these flavivirus and viral proteins on these biological processes. This not only provides a scientific basis for elucidating the pathogenesis of flavivirus, but also lays the foundation for the development of effective antiviral therapies.
Collapse
Affiliation(s)
- Yuhong Pan
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Wenjun Cai
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Anchun Cheng
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- *Correspondence: Renyong Jia, ; Anchun Cheng,
| | - Mingshu Wang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Zhongqiong Yin
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Renyong Jia
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- *Correspondence: Renyong Jia, ; Anchun Cheng,
| |
Collapse
|
7
|
Transcriptomic Studies Suggest a Coincident Role for Apoptosis and Pyroptosis but Not for Autophagic Neuronal Death in TBEV-Infected Human Neuronal/Glial Cells. Viruses 2021; 13:v13112255. [PMID: 34835061 PMCID: PMC8620470 DOI: 10.3390/v13112255] [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: 09/26/2021] [Revised: 11/01/2021] [Accepted: 11/04/2021] [Indexed: 12/19/2022] Open
Abstract
Tick-borne encephalitis virus (TBEV), a member of the Flaviviridae family, Flavivirus genus, is responsible for neurological symptoms that may cause permanent disability or death. With an incidence on the rise, it is the major arbovirus affecting humans in Central/Northern Europe and North-Eastern Asia. Neuronal death is a critical feature of TBEV infection, yet little is known about the type of death and the molecular mechanisms involved. In this study, we used a recently established pathological model of TBEV infection based on human neuronal/glial cells differentiated from fetal neural progenitors and transcriptomic approaches to tackle this question. We confirmed the occurrence of apoptotic death in these cultures and further showed that genes involved in pyroptotic death were up-regulated, suggesting that this type of death also occurs in TBEV-infected human brain cells. On the contrary, no up-regulation of major autophagic genes was found. Furthermore, we demonstrated an up-regulation of a cluster of genes belonging to the extrinsic apoptotic pathway and revealed the cellular types expressing them. Our results suggest that neuronal death occurs by multiple mechanisms in TBEV-infected human neuronal/glial cells, thus providing a first insight into the molecular pathways that may be involved in neuronal death when the human brain is infected by TBEV.
Collapse
|
8
|
Blahove MR, Carter JR. Flavivirus Persistence in Wildlife Populations. Viruses 2021; 13:v13102099. [PMID: 34696529 PMCID: PMC8541186 DOI: 10.3390/v13102099] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 10/01/2021] [Accepted: 10/08/2021] [Indexed: 12/14/2022] Open
Abstract
A substantial number of humans are at risk for infection by vector-borne flaviviruses, resulting in considerable morbidity and mortality worldwide. These viruses also infect wildlife at a considerable rate, persistently cycling between ticks/mosquitoes and small mammals and reptiles and non-human primates and humans. Substantially increasing evidence of viral persistence in wildlife continues to be reported. In addition to in humans, viral persistence has been shown to establish in mammalian, reptile, arachnid, and mosquito systems, as well as insect cell lines. Although a considerable amount of research has centered on the potential roles of defective virus particles, autophagy and/or apoptosis-induced evasion of the immune response, and the precise mechanism of these features in flavivirus persistence have yet to be elucidated. In this review, we present findings that aid in understanding how vector-borne flavivirus persistence is established in wildlife. Research studies to be discussed include determining the critical roles universal flavivirus non-structural proteins played in flaviviral persistence, the advancement of animal models of viral persistence, and studying host factors that allow vector-borne flavivirus replication without destructive effects on infected cells. These findings underscore the viral–host relationships in wildlife animals and could be used to elucidate the underlying mechanisms responsible for the establishment of viral persistence in these animals.
Collapse
|
9
|
Zika virus infection induced apoptosis by modulating the recruitment and activation of pro-apoptotic protein Bax. J Virol 2021; 95:JVI.01445-20. [PMID: 33536166 PMCID: PMC8103684 DOI: 10.1128/jvi.01445-20] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Zika virus (ZIKV) infection is associated with microcephaly in newborns and serious neurological complications in adults. Apoptosis of neural progenitor cells induced by ZIKV infection is believed to be a main reason for ZIKV infection-related microcephaly. However, the detailed mechanism of ZIKV infection-induced apoptosis remains to be elucidated. In this report, ZIKV infection induced the conformational activation of the pro-apoptotic protein Bax, with subsequent formation of oligomers of Bax in the mitochondria. Cell apoptosis was reduced significantly in SY5Y cells subjected to Bax knockdown. Additionally, while decreasing Bax expression inhibited the release of Cyt c from the mitochondria and reduced the rate of loss of mitochondrial membrane potential induced by ZIKV infection, silencing Bak, caspase-8, and/or caspase-10 expression did not. Mitochondria isolated from the untreated ZIKV-infected cells displayed Bax-binding ability and the subsequent release of Cyt c. This study also indicated that the NS4B protein of ZIKV recruited Bax to the mitochondria and induced Bax conformational activation. The overexpressed NS4B was localized to the mitochondria and induced cell apoptosis by activating the pro-apoptotic protein Bax. All the above results indicated that ZIKV infection directly impacted the mitochondrial apoptotic pathway by modulating the recruitment and activation of Bax.Importance: Since the large outbreaks that occurred in the Pacific Islands and Latin America in 2013, Zika virus has been confirmed a neuroteratogenic pathogen and causative agent of microcephaly and other developmental anomalies of the central nervous system in children born to infected mothers. As the widespread apoptosis throughout the whole brain, studies in animal models have reinforced the link between microcephaly caused by ZIKV infection and NPC apoptosis. Currently, the detailed mechanism of ZIKV infection-induced apoptosis still remains to be elucidated. Here, we firstly demonstrate that ZIKV infection activated the classic signs of mitochondrial apoptotic pathway by modulating the recruitment and activation of Bax. ZIKV NS4B represents a novel viral apoptotic protein that can modulate the recruitment and activation of Bax and trigger the apoptotic program. This is a new insight into understanding the interplay between apoptosis and ZIKV infection.
Collapse
|
10
|
Pan Y, Cheng A, Wang M, Yin Z, Jia R. The Dual Regulation of Apoptosis by Flavivirus. Front Microbiol 2021; 12:654494. [PMID: 33841381 PMCID: PMC8024479 DOI: 10.3389/fmicb.2021.654494] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Accepted: 02/25/2021] [Indexed: 12/11/2022] Open
Abstract
Apoptosis is a form of programmed cell death, which maintains cellular homeostasis by eliminating pathogen-infected cells. It contains three signaling pathways: death receptor pathway, mitochondria-mediated pathway, and endoplasmic reticulum pathway. Its importance in host defenses is highlighted by the observation that many viruses evade, hinder or destroy apoptosis, thereby weakening the host’s immune response. Flaviviruses such as Dengue virus, Japanese encephalitis virus, and West Nile virus utilize various strategies to activate or inhibit cell apoptosis. This article reviews the research progress of apoptosis mechanism during flaviviruses infection, including flaviviruses proteins and subgenomic flaviviral RNA to regulate apoptosis by interacting with host proteins, as well as various signaling pathways involved in flaviviruses-induced apoptosis, which provides a scientific basis for understanding the pathogenesis of flaviviruses and helps in developing an effective antiviral therapy.
Collapse
Affiliation(s)
- Yuhong Pan
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| | - Anchun Cheng
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| | - Mingshu Wang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| | - Zhongqiong Yin
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| | - Renyong Jia
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| |
Collapse
|
11
|
Yang S, Gorshkov K, Lee EM, Xu M, Cheng YS, Sun N, Soheilian F, de Val N, Ming G, Song H, Tang H, Zheng W. Zika Virus-Induced Neuronal Apoptosis via Increased Mitochondrial Fragmentation. Front Microbiol 2020; 11:598203. [PMID: 33424801 PMCID: PMC7785723 DOI: 10.3389/fmicb.2020.598203] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Accepted: 12/02/2020] [Indexed: 12/19/2022] Open
Abstract
The 2015 to 2016 outbreak of Zika virus (ZIKV) infections in the Americas coincided with a dramatic increase in neurodevelopmental abnormalities, including fetal microcephaly, in newborns born to infected women. In this study, we observed mitochondrial fragmentation and disrupted mitochondrial membrane potential after 24 h of ZIKV infection in human neural stem cells and the SNB-19 glioblastoma cell line. The severity of these changes correlated with the amount of ZIKV proteins expressed in infected cells. ZIKV infection also decreased the levels of mitofusin 2, which modulates mitochondria fusion. Mitochondrial division inhibitor 1 (Mdivi-1), a small molecule inhibiting mitochondria fission, ameliorated mitochondria disruptions and reduced cell death in ZIKV-infected cells. Collectively, this study suggests that abnormal mitochondrial fragmentation contributes to ZIKV-induced neuronal cell death; rebalancing mitochondrial dynamics of fission-fusion could be a therapeutic strategy for drug development to treat ZIKV-mediated neuronal apoptosis.
Collapse
Affiliation(s)
- Shu Yang
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, United States
| | - Kirill Gorshkov
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, United States
| | - Emily M Lee
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, United States
| | - Miao Xu
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, United States
| | - Yu-Shan Cheng
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, United States
| | - Nuo Sun
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH, United States
| | - Ferri Soheilian
- Electron Microscopy Laboratory, National Cancer Institute, Center for Cancer Research, Leidos Biomedical Research, Frederick National Laboratory, Frederick, MD, United States
| | - Natalia de Val
- Electron Microscopy Laboratory, National Cancer Institute, Center for Cancer Research, Leidos Biomedical Research, Frederick National Laboratory, Frederick, MD, United States
| | - Guoli Ming
- Department of Neuroscience, Mahoney Institute for Neurosciences, University of Pennsylvania, Philadelphia, PA, United States
| | - Hongjun Song
- Department of Neuroscience, Mahoney Institute for Neurosciences, University of Pennsylvania, Philadelphia, PA, United States
| | - Hengli Tang
- Department of Biological Science, Florida State University, Tallahassee, FL, United States
| | - Wei Zheng
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, United States
| |
Collapse
|
12
|
Fiacre L, Pagès N, Albina E, Richardson J, Lecollinet S, Gonzalez G. Molecular Determinants of West Nile Virus Virulence and Pathogenesis in Vertebrate and Invertebrate Hosts. Int J Mol Sci 2020; 21:ijms21239117. [PMID: 33266206 PMCID: PMC7731113 DOI: 10.3390/ijms21239117] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 11/23/2020] [Accepted: 11/26/2020] [Indexed: 12/12/2022] Open
Abstract
West Nile virus (WNV), like the dengue virus (DENV) and yellow fever virus (YFV), are major arboviruses belonging to the Flavivirus genus. WNV is emerging or endemic in many countries around the world, affecting humans and other vertebrates. Since 1999, it has been considered to be a major public and veterinary health problem, causing diverse pathologies, ranging from a mild febrile state to severe neurological damage and death. WNV is transmitted in a bird–mosquito–bird cycle, and can occasionally infect humans and horses, both highly susceptible to the virus but considered dead-end hosts. Many studies have investigated the molecular determinants of WNV virulence, mainly with the ultimate objective of guiding vaccine development. Several vaccines are used in horses in different parts of the world, but there are no licensed WNV vaccines for humans, suggesting the need for greater understanding of the molecular determinants of virulence and antigenicity in different hosts. Owing to technical and economic considerations, WNV virulence factors have essentially been studied in rodent models, and the results cannot always be transported to mosquito vectors or to avian hosts. In this review, the known molecular determinants of WNV virulence, according to invertebrate (mosquitoes) or vertebrate hosts (mammalian and avian), are presented and discussed. This overview will highlight the differences and similarities found between WNV hosts and models, to provide a foundation for the prediction and anticipation of WNV re-emergence and its risk of global spread.
Collapse
Affiliation(s)
- Lise Fiacre
- UMR 1161 Virology, ANSES, INRAE, ENVA, ANSES Animal Health Laboratory, EURL for Equine Diseases, 94704 Maisons-Alfort, France; (L.F.); (J.R.); (G.G.)
- CIRAD, UMR ASTRE, F-97170 Petit Bourg, Guadeloupe, France; (N.P.); (E.A.)
- ASTRE, University Montpellier, CIRAD, INRAE, F-34398 Montpellier, France
| | - Nonito Pagès
- CIRAD, UMR ASTRE, F-97170 Petit Bourg, Guadeloupe, France; (N.P.); (E.A.)
- ASTRE, University Montpellier, CIRAD, INRAE, F-34398 Montpellier, France
| | - Emmanuel Albina
- CIRAD, UMR ASTRE, F-97170 Petit Bourg, Guadeloupe, France; (N.P.); (E.A.)
- ASTRE, University Montpellier, CIRAD, INRAE, F-34398 Montpellier, France
| | - Jennifer Richardson
- UMR 1161 Virology, ANSES, INRAE, ENVA, ANSES Animal Health Laboratory, EURL for Equine Diseases, 94704 Maisons-Alfort, France; (L.F.); (J.R.); (G.G.)
| | - Sylvie Lecollinet
- UMR 1161 Virology, ANSES, INRAE, ENVA, ANSES Animal Health Laboratory, EURL for Equine Diseases, 94704 Maisons-Alfort, France; (L.F.); (J.R.); (G.G.)
- Correspondence: ; Tel.: +33-1-43967376
| | - Gaëlle Gonzalez
- UMR 1161 Virology, ANSES, INRAE, ENVA, ANSES Animal Health Laboratory, EURL for Equine Diseases, 94704 Maisons-Alfort, France; (L.F.); (J.R.); (G.G.)
| |
Collapse
|
13
|
Kobayashi S, Kaneko C, Kawakami R, Hasebe R, Sawa H, Yoshii K, Kariwa H. Amino acid 159 of the envelope protein affects viral replication and T-cell infiltration by West Nile virus in intracranial infection. Sci Rep 2020; 10:7168. [PMID: 32346055 PMCID: PMC7189269 DOI: 10.1038/s41598-020-64199-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 04/13/2020] [Indexed: 12/15/2022] Open
Abstract
West Nile virus (WNV) is an important cause of viral encephalitis in birds and animals, including humans. Amino acid 159 of the envelope (E) protein is reportedly implicated in the different levels of neurovirulence in mice infected with WNV NY99 or Eg101. We investigated the role of amino acid 159 of the E protein in the pathogenesis of WNV infection. We produced recombinant WNV with the structural proteins of the NY99 or Eg101 strain (NY-WT or EgCME-WT) and mutant viruses with substitutions of amino acid 159 of the E protein (NY-E-V159I or EgCME-E-I159V). The NY-WT and NY-E-V159I or EgCME-WT and EgCME-E-I159V titers in culture supernatant were similar. The mortality rate and viral titer in the brains of mice inoculated intraperitoneally with NY-WT or NY-E-V159I were also similar. In contrast, the mortality rate and viral titer in the brains of mice inoculated intracranially with EgCME-E-I159V were significantly higher than those of mice inoculated with EgCME-WT. The numbers of CD3-positive and CD8-positive T cells were greater in brains inoculated with EgCME-E-I159V than in those inoculated with EgCME-WT. Therefore, amino acid 159 of the E protein modulates the pathogenicity of WNV by affecting viral replication and T-cell infiltration in the brain.
Collapse
Affiliation(s)
- Shintaro Kobayashi
- Laboratory of Public Health, Faculty of Veterinary Medicine, Hokkaido University, N18, W9, Kita-ku, Sapporo, 060-0818, Japan.
| | - Chisato Kaneko
- Laboratory of Public Health, Faculty of Veterinary Medicine, Hokkaido University, N18, W9, Kita-ku, Sapporo, 060-0818, Japan
| | - Ryoko Kawakami
- Laboratory of Public Health, Faculty of Veterinary Medicine, Hokkaido University, N18, W9, Kita-ku, Sapporo, 060-0818, Japan
| | - Rie Hasebe
- Biomedical Animal Research Laboratory, Institute for Genetic Medicine, Hokkaido University, N15, W7, Kita-ku, Sapporo, 060-0815, Japan
| | - Hirofumi Sawa
- Division of Molecular Pathobiology, Research Center for Zoonosis Control, Hokkaido University, N20, W10, Kita-ku, Sapporo, 001-0020, Japan.,Global Institution for Collaborative Research and Education (GI-CoRE), Hokkaido University, Sapporo, Japan.,Global Virus Network, Baltimore, MD, USA
| | - Kentaro Yoshii
- Laboratory of Public Health, Faculty of Veterinary Medicine, Hokkaido University, N18, W9, Kita-ku, Sapporo, 060-0818, Japan
| | - Hiroaki Kariwa
- Laboratory of Public Health, Faculty of Veterinary Medicine, Hokkaido University, N18, W9, Kita-ku, Sapporo, 060-0818, Japan
| |
Collapse
|
14
|
Imre G. The involvement of regulated cell death forms in modulating the bacterial and viral pathogenesis. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2020; 353:211-253. [PMID: 32381176 PMCID: PMC7102569 DOI: 10.1016/bs.ircmb.2019.12.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Apoptosis, necroptosis and pyroptosis represent three distinct types of regulated cell death forms, which play significant roles in response to viral and bacterial infections. Whereas apoptosis is characterized by cell shrinkage, nuclear condensation, bleb formation and retained membrane integrity, necroptosis and pyroptosis exhibit osmotic imbalance driven cytoplasmic swelling and early membrane damage. These three cell death forms exert distinct immune stimulatory potential. The caspase driven apoptotic cell demise is considered in many circumstances as anti-inflammatory, whereas the two lytic cell death modalities can efficiently trigger immune response by releasing damage associated molecular patterns to the extracellular space. The relevance of these cell death modalities in infections can be best demonstrated by the presence of viral proteins that directly interfere with cell death pathways. Conversely, some pathogens hijack the cell death signaling routes to initiate a targeted attack against the immune cells of the host, and extracellular bacteria can benefit from the destruction of intact extracellular barriers upon cell death induction. The complexity and the crosstalk between these cell death modalities reflect a continuous evolutionary race between pathogens and host. This chapter discusses the current advances in the research of cell death signaling with regard to viral and bacterial infections and describes the network of the cell death initiating molecular mechanisms that selectively recognize pathogen associated molecular patterns.
Collapse
Affiliation(s)
- Gergely Imre
- Institute of General Pharmacology and Toxicology, University Hospital Frankfurt, Goethe University, Frankfurt am Main, Germany.
| |
Collapse
|
15
|
Peng BH, Wang T. West Nile Virus Induced Cell Death in the Central Nervous System. Pathogens 2019; 8:pathogens8040215. [PMID: 31683807 PMCID: PMC6963722 DOI: 10.3390/pathogens8040215] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 10/30/2019] [Accepted: 10/30/2019] [Indexed: 12/21/2022] Open
Abstract
West Nile virus (WNV), a mosquito-borne, single-stranded flavivirus, has caused annual outbreaks of viral encephalitis in the United States since 1999. The virus induces acute infection with a clinical spectrum ranging from a mild flu-like febrile symptom to more severe neuroinvasive conditions, including meningitis, encephalitis, acute flaccid paralysis, and death. Some WNV convalescent patients also developed long-term neurological sequelae. Neither the treatment of WNV infection nor an approved vaccine is currently available for humans. Neuronal death in the central nervous system (CNS) is a hallmark of WNV-induced meningitis and encephalitis. However, the underlying mechanisms of WNV-induced neuronal damage are not well understood. In this review, we discuss current findings from studies of WNV infection in vitro in the CNS resident cells and the in vivo animal models, and provide insights into WNV-induced neuropathogenesis.
Collapse
Affiliation(s)
- Bi-Hung Peng
- Department of Neuroscience, Cell Biology and Anatomy, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Tian Wang
- Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA.
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
- Sealy Institute for Vaccine Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA.
| |
Collapse
|
16
|
Oakes BL, Fellmann C, Rishi H, Taylor KL, Ren SM, Nadler DC, Yokoo R, Arkin AP, Doudna JA, Savage DF. CRISPR-Cas9 Circular Permutants as Programmable Scaffolds for Genome Modification. Cell 2019; 176:254-267.e16. [PMID: 30633905 PMCID: PMC6414052 DOI: 10.1016/j.cell.2018.11.052] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 08/21/2018] [Accepted: 11/28/2018] [Indexed: 12/20/2022]
Abstract
The ability to engineer natural proteins is pivotal to a future, pragmatic biology. CRISPR proteins have revolutionized genome modification, yet the CRISPR-Cas9 scaffold is not ideal for fusions or activation by cellular triggers. Here, we show that a topological rearrangement of Cas9 using circular permutation provides an advanced platform for RNA-guided genome modification and protection. Through systematic interrogation, we find that protein termini can be positioned adjacent to bound DNA, offering a straightforward mechanism for strategically fusing functional domains. Additionally, circular permutation enabled protease-sensing Cas9s (ProCas9s), a unique class of single-molecule effectors possessing programmable inputs and outputs. ProCas9s can sense a wide range of proteases, and we demonstrate that ProCas9 can orchestrate a cellular response to pathogen-associated protease activity. Together, these results provide a toolkit of safer and more efficient genome-modifying enzymes and molecular recorders for the advancement of precision genome engineering in research, agriculture, and biomedicine.
Collapse
Affiliation(s)
- Benjamin L Oakes
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Innovative Genomics Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Christof Fellmann
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Gladstone Institutes, San Francisco, CA 94158, USA
| | - Harneet Rishi
- Graduate Group in Biophysics, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Kian L Taylor
- Innovative Genomics Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Shawn M Ren
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Dana C Nadler
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Rayka Yokoo
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Adam P Arkin
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA 94720, USA; Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Jennifer A Doudna
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Innovative Genomics Institute, University of California, Berkeley, Berkeley, CA 94720, USA; Gladstone Institutes, San Francisco, CA 94158, USA; Graduate Group in Biophysics, University of California, Berkeley, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA; Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720, USA
| | - David F Savage
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA.
| |
Collapse
|
17
|
Uno N, Ross TM. Dengue virus and the host innate immune response. Emerg Microbes Infect 2018; 7:167. [PMID: 30301880 PMCID: PMC6177401 DOI: 10.1038/s41426-018-0168-0] [Citation(s) in RCA: 128] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 08/29/2018] [Accepted: 08/31/2018] [Indexed: 02/05/2023]
Abstract
Dengue virus (DENV) is a mosquito-borne Flavivirus that is endemic in many tropical and sub-tropical countries where the transmission vectors Aedes spp. mosquitoes resides. There are four serotypes of the virus. Each serotype is antigenically different, meaning they elicit heterologous antibodies. Infection with one serotype will create neutralizing antibodies to the serotype. Cross-protection from other serotypes is not long term, instead heterotypic infection can cause severe disease. This review will focus on the innate immune response to DENV infection and the virus evasion of the innate immune system by escaping recognition or inhibiting the production of an antiviral state. Activated innate immune pathways includes type I interferon, complement, apoptosis, and autophagy, which the virus can evade or exploit to exacerbate disease. It is important to understand out how the immune system reacts to infection and how the virus evades immune response in order to develop effective antivirals and vaccines.
Collapse
Affiliation(s)
- Naoko Uno
- Center for Vaccines and Immunology, University of Georgia, Athens, GA, USA
| | - Ted M Ross
- Center for Vaccines and Immunology, University of Georgia, Athens, GA, USA. .,Department of Infectious Diseases, University of Georgia, Athens, GA, USA.
| |
Collapse
|
18
|
Abstract
The persistence of West Nile virus (WNV) infections throughout the USA since its inception in 1999 and its continuous spread throughout the globe calls for an urgent need of effective treatments and prevention measures. Although the licensing of several WNV vaccines for veterinary use provides a proof of concept, similar efforts on the development of an effective vaccine for humans remain still unsuccessful. Increased understanding of biology and pathogenesis of WNV together with recent technological advancements have raised hope that an effective WNV vaccine may be available in the near future. In addition, rapid progress in the structural and functional characterization of WNV and other flaviviral proteins have provided a solid base for the design and development of several classes of inhibitors as potential WNV therapeutics. Moreover, the therapeutic monoclonal antibodies demonstrate an excellent efficacy against WNV in animal models and represent a promising class of WNV therapeutics. However, there are some challenges as to the design and development of a safe and efficient WNV vaccine or therapeutic. In this chapter, we discuss the current approaches, progress, and challenges toward the development of WNV vaccines, therapeutic antibodies, and antiviral drugs.
Collapse
|
19
|
Okamoto T, Suzuki T, Kusakabe S, Tokunaga M, Hirano J, Miyata Y, Matsuura Y. Regulation of Apoptosis during Flavivirus Infection. Viruses 2017; 9:v9090243. [PMID: 28846635 PMCID: PMC5618009 DOI: 10.3390/v9090243] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 08/19/2017] [Accepted: 08/25/2017] [Indexed: 02/06/2023] Open
Abstract
Apoptosis is a type of programmed cell death that regulates cellular homeostasis by removing damaged or unnecessary cells. Its importance in host defenses is highlighted by the observation that many viruses evade, obstruct, or subvert apoptosis, thereby blunting the host immune response. Infection with Flaviviruses such as Japanese encephalitis virus (JEV), Dengue virus (DENV) and West Nile virus (WNV) has been shown to activate several signaling pathways such as endoplasmic reticulum (ER)-stress and AKT/PI3K pathway, resulting in activation or suppression of apoptosis in virus-infected cells. On the other hands, expression of some viral proteins induces or protects apoptosis. There is a discrepancy between induction and suppression of apoptosis during flavivirus infection because the experimental situation may be different, and strong links between apoptosis and other types of cell death such as necrosis may make it more difficult. In this paper, we review the effects of apoptosis on viral propagation and pathogenesis during infection with flaviviruses.
Collapse
Affiliation(s)
- Toru Okamoto
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan.
| | - Tatsuya Suzuki
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan.
| | - Shinji Kusakabe
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan.
| | - Makoto Tokunaga
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan.
| | - Junki Hirano
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan.
| | - Yuka Miyata
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan.
| | - Yoshiharu Matsuura
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan.
| |
Collapse
|
20
|
Shives KD, Tyler KL, Beckham JD. Molecular mechanisms of neuroinflammation and injury during acute viral encephalitis. J Neuroimmunol 2017; 308:102-111. [DOI: 10.1016/j.jneuroim.2017.03.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 02/23/2017] [Accepted: 03/06/2017] [Indexed: 01/25/2023]
|
21
|
Non-Canonical Roles of Dengue Virus Non-Structural Proteins. Viruses 2017; 9:v9030042. [PMID: 28335410 PMCID: PMC5371797 DOI: 10.3390/v9030042] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 03/06/2017] [Accepted: 03/08/2017] [Indexed: 12/15/2022] Open
Abstract
The Flaviviridae family comprises a number of human pathogens, which, although sharing structural and functional features, cause diseases with very different outcomes. This can be explained by the plurality of functions exerted by the few proteins coded by viral genomes, with some of these functions shared among members of a same family, but others being unique for each virus species. These non-canonical functions probably have evolved independently and may serve as the base to the development of specific therapies for each of those diseases. Here it is discussed what is currently known about the non-canonical roles of dengue virus (DENV) non-structural proteins (NSPs), which may account for some of the effects specifically observed in DENV infection, but not in other members of the Flaviviridae family. This review explores how DENV NSPs contributes to the physiopathology of dengue, evasion from host immunity, metabolic changes, and redistribution of cellular components during infection.
Collapse
|
22
|
Characterization of cytopathic factors through genome-wide analysis of the Zika viral proteins in fission yeast. Proc Natl Acad Sci U S A 2017; 114:E376-E385. [PMID: 28049830 DOI: 10.1073/pnas.1619735114] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The Zika virus (ZIKV) causes microcephaly and the Guillain-Barré syndrome. Little is known about how ZIKV causes these conditions or which ZIKV viral protein(s) is responsible for the associated ZIKV-induced cytopathic effects, including cell hypertrophy, growth restriction, cell-cycle dysregulation, and cell death. We used fission yeast for the rapid, global functional analysis of the ZIKV genome. All 14 proteins or small peptides were produced under an inducible promoter, and we measured the intracellular localization and the specific effects on ZIKV-associated cytopathic activities of each protein. The subcellular localization of each ZIKV protein was in overall agreement with its predicted protein structure. Five structural and two nonstructural ZIKV proteins showed various levels of cytopathic effects. The expression of these ZIKV proteins restricted cell proliferation, induced hypertrophy, or triggered cellular oxidative stress leading to cell death. The expression of premembrane protein (prM) resulted in cell-cycle G1 accumulation, whereas membrane-anchored capsid (anaC), membrane protein (M), envelope protein (E), and nonstructural protein 4A (NS4A) caused cell-cycle G2/M accumulation. A mechanistic study revealed that NS4A-induced cellular hypertrophy and growth restriction were mediated specifically through the target of rapamycin (TOR) cellular stress pathway involving Tor1 and type 2A phosphatase activator Tip41. These findings should provide a reference for future research on the prevention and treatment of ZIKV diseases.
Collapse
|
23
|
Phoo WW, Li Y, Zhang Z, Lee MY, Loh YR, Tan YB, Ng EY, Lescar J, Kang C, Luo D. Structure of the NS2B-NS3 protease from Zika virus after self-cleavage. Nat Commun 2016; 7:13410. [PMID: 27845325 PMCID: PMC5116066 DOI: 10.1038/ncomms13410] [Citation(s) in RCA: 163] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Accepted: 09/30/2016] [Indexed: 12/22/2022] Open
Abstract
The recent outbreak of Zika virus (ZIKV) infections in the Americas represents a serious threat to the global public health. The viral protease that processes viral polyproteins during infection appears as an attractive drug target. Here we report a crystal structure at 1.84 Å resolution of ZIKV non-structural protein NS2B-NS3 protease with the last four amino acids of the NS2B cofactor bound at the NS3 active site. This structure represents a post-proteolysis state of the enzyme during viral polyprotein processing and provides insights into peptide substrate recognition by the protease. Nuclear magnetic resonance (NMR) studies and protease activity assays unravel the protein dynamics upon binding the protease inhibitor BPTI in solution and confirm this finding. The structural and functional insights of the ZIKV protease presented here should advance our current understanding of flavivirus replication and accelerate structure-based antiviral drug discovery against ZIKV. The proteases of flaviviruses are promising targets for development of specific antiviral drugs. Here, the authors report a high resolution crystal structure of the NS2B-NS3 protease of Zika virus that provides insight into substrate and inhibitor binding.
Collapse
Affiliation(s)
- Wint Wint Phoo
- Lee Kong Chian School of Medicine, Nanyang Technological University, EMB 03-07, 59 Nanyang Drive, Singapore 636921, Singapore.,School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 636921, Singapore.,NTU Institute of Structural Biology, Nanyang Technological University, EMB 06-01, 59 Nanyang Drive, Singapore 636921, Singapore
| | - Yan Li
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis way, Nanos, #03-01, Singapore 138669, Singapore
| | - Zhenzhen Zhang
- Lee Kong Chian School of Medicine, Nanyang Technological University, EMB 03-07, 59 Nanyang Drive, Singapore 636921, Singapore.,NTU Institute of Structural Biology, Nanyang Technological University, EMB 06-01, 59 Nanyang Drive, Singapore 636921, Singapore
| | - Michelle Yueqi Lee
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis way, Nanos, #03-01, Singapore 138669, Singapore
| | - Ying Ru Loh
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis way, Nanos, #03-01, Singapore 138669, Singapore
| | - Yaw Bia Tan
- Lee Kong Chian School of Medicine, Nanyang Technological University, EMB 03-07, 59 Nanyang Drive, Singapore 636921, Singapore.,NTU Institute of Structural Biology, Nanyang Technological University, EMB 06-01, 59 Nanyang Drive, Singapore 636921, Singapore
| | - Elizabeth Yihui Ng
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis way, Nanos, #03-01, Singapore 138669, Singapore
| | - Julien Lescar
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 636921, Singapore.,NTU Institute of Structural Biology, Nanyang Technological University, EMB 06-01, 59 Nanyang Drive, Singapore 636921, Singapore
| | - CongBao Kang
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis way, Nanos, #03-01, Singapore 138669, Singapore
| | - Dahai Luo
- Lee Kong Chian School of Medicine, Nanyang Technological University, EMB 03-07, 59 Nanyang Drive, Singapore 636921, Singapore.,School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 636921, Singapore.,NTU Institute of Structural Biology, Nanyang Technological University, EMB 06-01, 59 Nanyang Drive, Singapore 636921, Singapore
| |
Collapse
|
24
|
Gruba N, Rodriguez Martinez JI, Grzywa R, Wysocka M, Skoreński M, Burmistrz M, Łęcka M, Lesner A, Sieńczyk M, Pyrć K. Substrate profiling of Zika virus NS2B-NS3 protease. FEBS Lett 2016; 590:3459-3468. [PMID: 27714789 DOI: 10.1002/1873-3468.12443] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 09/12/2016] [Accepted: 09/22/2016] [Indexed: 01/05/2023]
Abstract
Zika virus (ZIKV), isolated from macaques in Uganda in 1947, was not considered to be a dangerous human pathogen. However, this view has recently changed as ZIKV infections are now associated with serious pathological disorders including microcephaly and Guillain-Barré syndrome. Similar to other viruses in the Flaviviridae family, ZIKV expresses the serine protease NS3 which is responsible for viral protein processing and replication. Herein, we report the expression of an active NS3pro domain fused with the NS2B cofactor (NS2BLN NS3pro ) in a prokaryotic expression system and profile its specificity for synthesized FRET-type substrate libraries. Our findings pave way for screening potential intracellular substrates of NS3 and for developing specific inhibitors of this ZIKV protease.
Collapse
Affiliation(s)
- Natalia Gruba
- Department of Biochemistry, Faculty of Chemistry, University of Gdansk, Poland
| | | | - Renata Grzywa
- Division of Medicinal Chemistry and Microbiology, Faculty of Chemistry, Wroclaw University of Science and Technology, Wroclaw, Poland
| | - Magdalena Wysocka
- Department of Biochemistry, Faculty of Chemistry, University of Gdansk, Poland
| | - Marcin Skoreński
- Division of Medicinal Chemistry and Microbiology, Faculty of Chemistry, Wroclaw University of Science and Technology, Wroclaw, Poland
| | - Michał Burmistrz
- Department of Microbiology, Faculty of Biochemistry Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland.,Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland
| | - Maria Łęcka
- Division of Medicinal Chemistry and Microbiology, Faculty of Chemistry, Wroclaw University of Science and Technology, Wroclaw, Poland
| | - Adam Lesner
- Department of Biochemistry, Faculty of Chemistry, University of Gdansk, Poland.
| | - Marcin Sieńczyk
- Division of Medicinal Chemistry and Microbiology, Faculty of Chemistry, Wroclaw University of Science and Technology, Wroclaw, Poland.
| | - Krzysztof Pyrć
- Department of Microbiology, Faculty of Biochemistry Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland. .,Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland.
| |
Collapse
|
25
|
Yuan S, Zhang N, Xu L, Zhou L, Ge X, Guo X, Yang H. Induction of Apoptosis by the Nonstructural Protein 4 and 10 of Porcine Reproductive and Respiratory Syndrome Virus. PLoS One 2016; 11:e0156518. [PMID: 27310256 PMCID: PMC4911139 DOI: 10.1371/journal.pone.0156518] [Citation(s) in RCA: 20] [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: 02/02/2016] [Accepted: 05/16/2016] [Indexed: 12/16/2022] Open
Abstract
Infection by most viruses triggers apoptosis in host cells, and viruses manipulate this cell response to promote viral replication, virus spread, and cell killing. Porcine reproductive and respiratory syndrome virus (PRRSV) has been shown to induce apoptosis both in vitro and in vivo, while the regulatory roles of PRRSV-encoded products in apoptosis are not fully understood. In the present study, we first showed a biphasic apoptosis regulation by a highly pathogenic PRRSV strain JXwn06. It was indicated that PRRSV infection delays apoptosis at early infection but activates apoptosis at late infection in MARC-145 cells. In PRRSV-infected MARC-145 cells, procaspase-8, -9 and -12 were activated at late infection, demonstrating the involvements of death receptor pathway, mitochondrial pathway and endoplasmic reticulum (ER) stress pathway in inducing apoptosis. PRRSV was also shown to induce a similar apoptosis process in pulmonary alveolar macrophages (PAMs) with an early initiation. Next, the PRRSV-encoded apoptosis inducers were screened, indicating that the nonstructural protein (Nsp) 4 and Nsp10 of PRRSV are pro-apoptotic. In the presence of Nsp4, it was confirmed that procaspase-8, -9 and -12 were cleaved, and Nsp4 facilitates the cleavage of procaspase-9 by activating B-cell lymphoma 2 interacting mediator of cell death (Bim), a pro-apoptotic protein. In addition, Nsp4 was shown to induce the degradation of an anti-apoptotic protein, B-cell lymphoma-extra large (Bcl-xL). Nsp10 was shown to activate procaspase-8 and -9 but procaspase-12 and to upregulate the expression of BH3-only pro-apoptotic protein BH3 interacting-domain death agonist (Bid) and its active form, truncated Bid (tBid). Clearly, the participation of both activated caspase-8 and Bid is required for Nsp10-induced apoptosis, indicating a crosstalk between extrinsic- and mitochondria-dependent pathways. Together, our findings suggest that PRRSV infection regulates apoptosis in a two-phase manner and activates all three apoptotic pathways; the Nsp4 and Nsp10 of PRRSV function as apoptosis inducers with different molecular basis.
Collapse
Affiliation(s)
- Shuaizhen Yuan
- Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, People’s Republic of China
| | - Ning Zhang
- Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, People’s Republic of China
| | - Lei Xu
- Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, People’s Republic of China
| | - Lei Zhou
- Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, People’s Republic of China
| | - Xinna Ge
- Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, People’s Republic of China
| | - Xin Guo
- Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, People’s Republic of China
| | - Hanchun Yang
- Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, People’s Republic of China
- State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing, People’s Republic of China
- * E-mail:
| |
Collapse
|
26
|
Uddin MJ, Suen WW, Prow NA, Hall RA, Bielefeldt-Ohmann H. West Nile Virus Challenge Alters the Transcription Profiles of Innate Immune Genes in Rabbit Peripheral Blood Mononuclear Cells. Front Vet Sci 2015; 2:76. [PMID: 26697438 PMCID: PMC4677099 DOI: 10.3389/fvets.2015.00076] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 11/30/2015] [Indexed: 11/13/2022] Open
Abstract
The peripheral innate immune response to West Nile virus (WNV) is crucial for control of virus spread to the central nervous system. Therefore, transcriptomes encoding the innate immune response proteins against WNV were investigated in peripheral blood mononuclear cells (PBMCs) of New Zealand White rabbits, a recently established novel rabbit model for WNV pathogenesis studies. PBMCs were challenged with an Australian WNV strain, WNVNSW2011, in vitro, and mRNA expression of selected immune response genes were quantified at 2-, 6-, 12-, and 24-h post-infection (pi) using qRT-PCR. Compared to mock-inoculated PBMCs, WNV-stimulated PBMCs expressed high levels of interferon (IFN) alpha (IFNA), gamma (IFNG), IL6, IL12, IL22, CXCL10, and pentraxin 3 (PTX3) mRNA. Likewise, TLR1, 2, 3, 4, 6, and 10 mRNA became up-regulated with the highest expression seen for TLR3, 4, and 6. TLRs-signaling downstream genes (MyD88, STAT1, TRAF3, IRF7, and IRF9) subsequently became up-regulated. The high expression of IFNs, TLR3, TLR4, TRAF3, STAT1, IRF7, and IRF9 are in accordance with antiviral activities, while expression of TNFA, HO1, iNOS, caspase 3, and caspase 9 transcripts suggests the involvement of oxidative stress and apoptosis in WNV-stimulated rabbit PBMCs, respectively. The level of WNVNSW2011 RNA increased at 24-h pi in PBMCs challenged with virus in vitro compared to input virus. The expression dynamics of selected genes were validated in PBMCs from rabbits experimentally infected with WNV in vivo. Higher expression of IFNA, IFN beta (IFNB), IFNG, TNFA, IL6, IL22, PTX3, TLR3 and TLR4, IRF7, IRF9, STST1, TRAF3, caspase 3, and caspase 9 were seen in PBMCs from WNV-infected rabbits on day 3 post-intradermal virus inoculation compared to PBMCs from uninfected control rabbits. This study highlights the array of cytokines and TLRs involved in the host innate immune response to WNV in the rabbit leukocytes and suggests that these cells may be a useful in vitro model for WNV infection study.
Collapse
Affiliation(s)
- Muhammad J Uddin
- School of Veterinary Science, University of Queensland , Gatton, QLD , Australia
| | - Willy W Suen
- School of Veterinary Science, University of Queensland , Gatton, QLD , Australia
| | - Natalie A Prow
- QIMR Berghofer Medical Research Institute , Brisbane, QLD , Australia
| | - Roy A Hall
- Australian Infectious Diseases Research Centre, University of Queensland , St Lucia, QLD , Australia ; School of Chemistry and Molecular Biosciences, University of Queensland , St Lucia, QLD , Australia
| | - Helle Bielefeldt-Ohmann
- School of Veterinary Science, University of Queensland , Gatton, QLD , Australia ; Australian Infectious Diseases Research Centre, University of Queensland , St Lucia, QLD , Australia ; School of Chemistry and Molecular Biosciences, University of Queensland , St Lucia, QLD , Australia
| |
Collapse
|
27
|
Luo D, Vasudevan SG, Lescar J. The flavivirus NS2B-NS3 protease-helicase as a target for antiviral drug development. Antiviral Res 2015; 118:148-58. [PMID: 25842996 DOI: 10.1016/j.antiviral.2015.03.014] [Citation(s) in RCA: 192] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Revised: 03/20/2015] [Accepted: 03/26/2015] [Indexed: 11/30/2022]
Abstract
The flavivirus NS3 protein is associated with the endoplasmic reticulum membrane via its close interaction with the central hydrophilic region of the NS2B integral membrane protein. The multiple roles played by the NS2B-NS3 protein in the virus life cycle makes it an attractive target for antiviral drug discovery. The N-terminal region of NS3 and its cofactor NS2B constitute the protease that cleaves the viral polyprotein. The NS3 C-terminal domain possesses RNA helicase, nucleoside and RNA triphosphatase activities and is involved both in viral RNA replication and virus particle formation. In addition, NS2B-NS3 serves as a hub for the assembly of the flavivirus replication complex and also modulates viral pathogenesis and the host immune response. Here, we review biochemical and structural advances on the NS2B-NS3 protein, including the network of interactions it forms with NS5 and NS4B and highlight recent drug development efforts targeting this protein. This article forms part of a symposium in Antiviral Research on flavivirus drug discovery.
Collapse
Affiliation(s)
- Dahai Luo
- Lee Kong Chian School of Medicine, Nanyang Technological University, 61 Biopolis Drive, Proteos Building, #07-03, Singapore 138673, Singapore.
| | - Subhash G Vasudevan
- Program in Emerging Infectious Diseases, DUKE-NUS Graduate Medical School, 8 College Road, Singapore 169857, Singapore.
| | - Julien Lescar
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore; UPMC UMRS CR7 - CNRS ERL 8255-INSERM U1135 Centre d'Immunologie et des Maladies Infectieuses, Centre Hospitalier Universitaire Pitié-Salpêtrière, Faculté de Médecine Pierre et Marie Curie, Paris, France.
| |
Collapse
|
28
|
Shubin AV, Demidyuk IV, Lunina NA, Komissarov AA, Roschina MP, Leonova OG, Kostrov SV. Protease 3C of hepatitis A virus induces vacuolization of lysosomal/endosomal organelles and caspase-independent cell death. BMC Cell Biol 2015; 16:4. [PMID: 25886889 PMCID: PMC4355371 DOI: 10.1186/s12860-015-0050-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 01/26/2015] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND 3C proteases, the main proteases of picornaviruses, play the key role in viral life cycle by processing polyproteins. In addition, 3C proteases digest certain host cell proteins to suppress antiviral defense, transcription, and translation. The activity of 3C proteases per se induces host cell death, which makes them critical factors of viral cytotoxicity. To date, cytotoxic effects have been studied for several 3C proteases, all of which induce apoptosis. This study for the first time describes the cytotoxic effect of 3C protease of human hepatitis A virus (3Cpro), the only proteolytic enzyme of the virus. RESULTS Individual expression of 3Cpro induced catalytic activity-dependent cell death, which was not abrogated by the pan-caspase inhibitor (z-VAD-fmk) and was not accompanied by phosphatidylserine externalization in contrast to other picornaviral 3C proteases. The cell survival was also not affected by the inhibitors of cysteine proteases (z-FA-fmk) and RIP1 kinase (necrostatin-1), critical enzymes involved in non-apoptotic cell death. A substantial fraction of dying cells demonstrated numerous non-acidic cytoplasmic vacuoles with not previously described features and originating from several types of endosomal/lysosomal organelles. The lysosomal protein Lamp1 and GTPases Rab5, Rab7, Rab9, and Rab11 were associated with the vacuolar membranes. The vacuolization was completely blocked by the vacuolar ATPase inhibitor (bafilomycin A1) and did not depend on the activity of the principal factors of endosomal transport, GTPases Rab5 and Rab7, as well as on autophagy and macropinocytosis. CONCLUSIONS 3Cpro, apart from other picornaviral 3C proteases, induces caspase-independent cell death, accompanying by cytoplasmic vacuolization. 3Cpro-induced vacuoles have unique properties and are formed from several organelle types of the endosomal/lysosomal compartment. The data obtained demonstrate previously undocumented morphological characters of the 3Cpro-induced cell death, which can reflect unknown aspects of the human hepatitis A virus-host cell interaction.
Collapse
Affiliation(s)
- Andrey V Shubin
- Laboratory of Protein Engineering, Institute of Molecular Genetics, Russian Academy of Science, Moscow, 123182, Russia.
| | - Ilya V Demidyuk
- Laboratory of Protein Engineering, Institute of Molecular Genetics, Russian Academy of Science, Moscow, 123182, Russia.
| | - Nataliya A Lunina
- Laboratory of Protein Engineering, Institute of Molecular Genetics, Russian Academy of Science, Moscow, 123182, Russia.
| | - Alexey A Komissarov
- Laboratory of Protein Engineering, Institute of Molecular Genetics, Russian Academy of Science, Moscow, 123182, Russia.
| | - Marina P Roschina
- Laboratory of Protein Engineering, Institute of Molecular Genetics, Russian Academy of Science, Moscow, 123182, Russia.
| | - Olga G Leonova
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, 119992, Russia.
| | - Sergey V Kostrov
- Laboratory of Protein Engineering, Institute of Molecular Genetics, Russian Academy of Science, Moscow, 123182, Russia.
- National Research Center "Kurchatov Institute", Moscow, 123182, Russia.
| |
Collapse
|
29
|
Myint KSA, Kipar A, Jarman RG, Gibbons RV, Perng GC, Flanagan B, Mongkolsirichaikul D, Van Gessel Y, Solomon T. Neuropathogenesis of Japanese encephalitis in a primate model. PLoS Negl Trop Dis 2014; 8:e2980. [PMID: 25102067 PMCID: PMC4125110 DOI: 10.1371/journal.pntd.0002980] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Accepted: 05/13/2014] [Indexed: 11/19/2022] Open
Abstract
Background Japanese encephalitis (JE) is a major cause of mortality and morbidity for which there is no treatment. In addition to direct viral cytopathology, the inflammatory response is postulated to contribute to the pathogenesis. Our goal was to determine the contribution of bystander effects and inflammatory mediators to neuronal cell death. Methodology/Principal Findings Material from a macaque model was used to characterize the inflammatory response and cytopathic effects of JE virus (JEV). Intranasal JEV infection induced a non-suppurative encephalitis, dominated by perivascular, infiltrates of mostly T cells, alongside endothelial cell activation, vascular damage and blood brain barrier (BBB) leakage; in the adjacent parenchyma there was macrophage infiltration, astrocyte and microglia activation. JEV antigen was mostly in neurons, but there was no correlation between intensity of viral infection and degree of inflammatory response. Apoptotic cell death occurred in both infected and non-infected neurons. Interferon-α, which is a microglial activator, was also expressed by both. Tumour Necrosis Factor-α, inducible nitric oxide synthase and nitrotyrosine were expressed by microglial cells, astrocytes and macrophages. The same cells expressed matrix metalloproteinase (MMP)-2 whilst MMP-9 was expressed by neurons. Conclusions/Significance The results are consistent with JEV inducing neuronal apoptotic death and release of cytokines that initiate microglial activation and release of pro-inflammatory and apoptotic mediators with subsequent apoptotic death of both infected and uninfected neurons. Activation of astrocytes, microglial and endothelial cells likely contributes to inflammatory cell recruitment and BBB breakdown. It appears that neuronal apoptotic death and activation of microglial cells and astrocytes play a crucial role in the pathogenesis of JE. Japanese encephalitis (JE) is one of the most important causes of viral encephalitis worldwide, with no specific antiviral treatment available. Despite some recent successes with widespread vaccination, JE will likely remain an important public health problem; because the virus is mosquito-borne and has natural animal hosts, it will never be eradicated. We have little understanding of what determines the severity and outcome of infection. Data from human post mortem studies is very limited because of cultural constraints on autopsies in areas where JE occurs. Circumstantial evidence suggests that in addition to cytopathology caused directly by infection of neurons, there may be bystander cell death of non-infected neurons, caused by an excessive inflammatory response. Our study used archived brain samples from a prior challenge study in a validated macaque model of JE. We stained for the presence of JEV antigen, apoptosis, and pro-inflammatory markers in affected areas, such as the thalamus and brainstem. We show that bystander neuronal cell death is important, and elucidate the inflammatory and apoptotic mechanisms underlying it. Currently there is no proven efficacious therapy for most viral infections of the central nervous system, including JE. Novel strategies for treating such infections are urgently needed. Our findings suggest new anti-inflammatory and anti-apoptotic therapeutic approaches may be useful in treating this debilitating disease.
Collapse
Affiliation(s)
- Khin Saw Aye Myint
- Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok, Thailand
- Brain Infections Group, Institute of Infection and Global Health, University of Liverpool, NIHR Health Protection Research Unit in Emerging and Zoonotic Infections, and Walton Centre NHS Foundation Trust, Liverpool, United Kingdom
| | - Anja Kipar
- Veterinary Pathology, School of Veterinary Science, and Department of Infection Biology, Institute of Global Health, University of Liverpool, Liverpool, United Kingdom
| | - Richard G. Jarman
- Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok, Thailand
| | - Robert V. Gibbons
- Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok, Thailand
| | - Guey Chuen Perng
- Emory Vaccine Center, Emory University School of Medicine, Atlanta, Georgia, United States of America
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Center of Infectious Disease and Signal Research, National Cheng Kung University, Tainan, Taiwan
| | - Brian Flanagan
- Infection Immunology, Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool, United Kingdom
| | | | - Yvonne Van Gessel
- Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok, Thailand
| | - Tom Solomon
- Brain Infections Group, Institute of Infection and Global Health, University of Liverpool, NIHR Health Protection Research Unit in Emerging and Zoonotic Infections, and Walton Centre NHS Foundation Trust, Liverpool, United Kingdom
- * E-mail:
| |
Collapse
|
30
|
Lin JC, Lin SC, Chen WY, Yen YT, Lai CW, Tao MH, Lin YL, Miaw SC, Wu-Hsieh BA. Dengue viral protease interaction with NF-κB inhibitor α/β results in endothelial cell apoptosis and hemorrhage development. THE JOURNAL OF IMMUNOLOGY 2014; 193:1258-67. [PMID: 24973451 DOI: 10.4049/jimmunol.1302675] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Hemorrhagic manifestations occur frequently accompanying a wide range of dengue disease syndromes. Much work has focused on the contribution of immune factors to the pathogenesis of hemorrhage, but how dengue virus (DENV) participates in the pathogenic process has never been explored. Although there is no consensus that apoptosis is the basis of vascular permeability in human dengue infections, we showed in dengue hemorrhage mouse model that endothelial cell apoptosis is important to hemorrhage development in mice. To explore the molecular basis of the contribution of DENV to endothelial cell death, we show in this study that DENV protease interacts with cellular IκBα and IκBβ and cleaves them. By inducing IκBα and IκBβ cleavage and IκB kinase activation, DENV protease activates NF-κB, which results in endothelial cell death. Intradermal inoculation of DENV protease packaged in adenovirus-associated virus-9 induces endothelial cell death and dermal hemorrhage in mice. Although the H51 activity site is not involved in the interaction between DENV protease and IκB-α/β, the enzymatic activity is critical to the ability of DENV protease to induce IκBα and IκBβ cleavage and trigger hemorrhage development. Moreover, overexpression of IκBα or IκBβ protects endothelial cells from DENV-induced apoptosis. In this study, we show that DENV protease participates in the pathogenesis of dengue hemorrhage and discover IκBα and IκBβ to be the new cellular targets that are cleaved by DENV protease.
Collapse
Affiliation(s)
- Jung-Chen Lin
- Graduate Institute of Immunology, National Taiwan University College of Medicine, Taipei 100, Taiwan
| | - Shih-Ching Lin
- Graduate Institute of Immunology, National Taiwan University College of Medicine, Taipei 100, Taiwan
| | - Wen-Yu Chen
- Graduate Institute of Immunology, National Taiwan University College of Medicine, Taipei 100, Taiwan
| | - Yu-Ting Yen
- Graduate Institute of Immunology, National Taiwan University College of Medicine, Taipei 100, Taiwan
| | - Chin-Wen Lai
- Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei 100, Taiwan; and Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Mi-Hua Tao
- Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei 100, Taiwan; and Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Yi-Ling Lin
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Shi-Chuen Miaw
- Graduate Institute of Immunology, National Taiwan University College of Medicine, Taipei 100, Taiwan
| | - Betty A Wu-Hsieh
- Graduate Institute of Immunology, National Taiwan University College of Medicine, Taipei 100, Taiwan;
| |
Collapse
|
31
|
Neal JW. Flaviviruses are neurotropic, but how do they invade the CNS? J Infect 2014; 69:203-15. [PMID: 24880028 DOI: 10.1016/j.jinf.2014.05.010] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2014] [Revised: 05/10/2014] [Accepted: 05/19/2014] [Indexed: 12/17/2022]
Abstract
Flaviruses (FV) are RNA viruses carried by mosquitoes. Neurological signs including acute encephalitis, meningitis and acute flaccid paralysis develop in a small percentage of infected individuals; long term sequlae are, Parkinsonism, dystonias and cognitive changes. FV neuroinfection is neurotropic involving subcortical nuclei (substantia nigra and thalamus) anterior horn neurons and neocortex. Glycosylation of the FV E envelope protein is one determinant of neuroinvasion, increasing both axonal and trans-epithelial transportation. Neutralizing antibodies against the E and NS proteins prevents FV uptake into several cell types, including axons. CD8+ T cells are vital for clearance of WNF infected cells from the CNS, whereas TLR-3 and TLR-7 mediated anti-virus response through increased serum inflammatory cytokines to disrupt the BBB providing infected leucocytes and free virus access to the CNS (so called Trojan horse) Cellular virus attachment factors, promoting FV cell entry are widely distributed and include DC-SIGN (that detects complex carbohydrate molecules); Glycosamino glycans (GAG), Heparan sulphate(HSPG) Semaphorin 7A, Low Density Lipid receptors (LDLR); these are not FV specific virus entry receptors. The FV also crosses epithelial and endothelial barriers by disrupting Tight Junction complexes to increase BBB permeability. This review describes the multiple pathways responsible for the neuroinvasive properties of the Flaviviruses.
Collapse
Affiliation(s)
- J W Neal
- Institute of Infection and Immunity, Henry Wellcome Building, University Hospital of Wales, Cardiff University, Cardiff CF14 4XN, United Kingdom.
| |
Collapse
|
32
|
Ghosh Roy S, Sadigh B, Datan E, Lockshin RA, Zakeri Z. Regulation of cell survival and death during Flavivirus infections. World J Biol Chem 2014; 5:93-105. [PMID: 24921001 PMCID: PMC4050121 DOI: 10.4331/wjbc.v5.i2.93] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Revised: 02/27/2014] [Accepted: 04/29/2014] [Indexed: 02/05/2023] Open
Abstract
Flaviviruses, ss(+) RNA viruses, include many of mankind’s most important pathogens. Their pathogenicity derives from their ability to infect many types of cells including neurons, to replicate, and eventually to kill the cells. Flaviviruses can activate tumor necrosis factor α and both intrinsic (Bax-mediated) and extrinsic pathways to apoptosis. Thus they can use many approaches for activating these pathways. Infection can lead to necrosis if viral load is extremely high or to other types of cell death if routes to apoptosis are blocked. Dengue and Japanese Encephalitis Virus can also activate autophagy. In this case the autophagy temporarily spares the infected cell, allowing a longer period of reproduction for the virus, and the autophagy further protects the cell against other stresses such as those caused by reactive oxygen species. Several of the viral proteins have been shown to induce apoptosis or autophagy on their own, independent of the presence of other viral proteins. Given the versatility of these viruses to adapt to and manipulate the metabolism, and thus to control the survival of, the infected cells, we need to understand much better how the specific viral proteins affect the pathways to apoptosis and autophagy. Only in this manner will we be able to minimize the pathology that they cause.
Collapse
|
33
|
Mlera L, Melik W, Bloom ME. The role of viral persistence in flavivirus biology. Pathog Dis 2014; 71:137-63. [PMID: 24737600 PMCID: PMC4154581 DOI: 10.1111/2049-632x.12178] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 04/08/2014] [Accepted: 04/09/2014] [Indexed: 12/30/2022] Open
Abstract
In nature, vector borne flaviviruses are persistently cycled between either the tick or mosquito vector and small mammals such as rodents, skunks, and swine. These viruses account for considerable human morbidity and mortality worldwide. Increasing and substantial evidence of viral persistence in humans, which includes the isolation of RNA by RT PCR and infectious virus by culture, continues to be reported. Viral persistence can also be established in vitro in various human, animal, arachnid, and insect cell lines in culture. Although some research has focused on the potential roles of defective virus particles, evasion of the immune response through the manipulation of autophagy and/or apoptosis, the precise mechanism of flavivirus persistence is still not well understood. We propose additional research for further understanding of how viral persistence is established in different systems. Avenues for additional studies include determining whether the multifunctional flavivirus protein NS5 has a role in viral persistence, the development of relevant animal models of viral persistence, and investigating the host responses that allow vector borne flavivirus replication without detrimental effects on infected cells. Such studies might shed more light on the viral–host relationships and could be used to unravel the mechanisms for establishment of persistence. Persistent infections by vector borne flaviviruses are an important, but inadequately studied topic.
Collapse
Affiliation(s)
- Luwanika Mlera
- Rocky Mountain Laboratories, Laboratory of Virology, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, USA
| | | | | |
Collapse
|
34
|
Functional interplay among the flavivirus NS3 protease, helicase, and cofactors. Virol Sin 2014; 29:74-85. [PMID: 24691778 DOI: 10.1007/s12250-014-3438-6] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Accepted: 03/19/2014] [Indexed: 12/22/2022] Open
Abstract
Flaviviruses are positive-sense RNA viruses, and many are important human pathogens. Nonstructural protein 2B and 3 of the flaviviruses (NS2BNS3) form an endoplasmic reticulum (ER) membrane-associated hetero-dimeric complex through the NS2B transmembrane region. The NS2BNS3 complex is multifunctional. The N-terminal region of NS3, and its cofactor NS2B fold into a protease that is responsible for viral polyprotein processing, and the C-terminal domain of NS3 possesses NTPase/RNA helicase activities and is involved in viral RNA replication and virus particle formation. In addition, NS2BNS3 complex has also been shown to modulate viral pathogenesis and the host immune response. Because of the essential functions that the NS2BNS3 complex plays in the flavivirus life cycle, it is an attractive target for antiviral development. This review focuses on the recent biochemical and structural advances of NS2BNS3 and provides a brief update on the current status of drug development targeting this viral protein complex.
Collapse
|
35
|
Lim SP, Shi PY. West Nile virus drug discovery. Viruses 2013; 5:2977-3006. [PMID: 24300672 PMCID: PMC3967157 DOI: 10.3390/v5122977] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Revised: 11/25/2013] [Accepted: 11/25/2013] [Indexed: 02/08/2023] Open
Abstract
The outbreak of West Nile virus (WNV) in 1999 in the USA, and its continued spread throughout the Americas, parts of Europe, the Middle East and Africa, underscored the need for WNV antiviral development. Here, we review the current status of WNV drug discovery. A number of approaches have been used to search for inhibitors of WNV, including viral infection-based screening, enzyme-based screening, structure-based virtual screening, structure-based rationale design, and antibody-based therapy. These efforts have yielded inhibitors of viral or cellular factors that are critical for viral replication. For small molecule inhibitors, no promising preclinical candidate has been developed; most of the inhibitors could not even be advanced to the stage of hit-to-lead optimization due to their poor drug-like properties. However, several inhibitors developed for related members of the family Flaviviridae, such as dengue virus and hepatitis C virus, exhibited cross-inhibition of WNV, suggesting the possibility to re-purpose these antivirals for WNV treatment. Most promisingly, therapeutic antibodies have shown excellent efficacy in mouse model; one of such antibodies has been advanced into clinical trial. The knowledge accumulated during the past fifteen years has provided better rationale for the ongoing WNV and other flavivirus antiviral development.
Collapse
Affiliation(s)
- Siew Pheng Lim
- Novartis Institute for Tropical Diseases, 10 Biopolis Road, Chromos 05-01, Singapore 138670, Singapore.
| | | |
Collapse
|
36
|
Donadieu E, Bahuon C, Lowenski S, Zientara S, Coulpier M, Lecollinet S. Differential virulence and pathogenesis of West Nile viruses. Viruses 2013; 5:2856-80. [PMID: 24284878 PMCID: PMC3856419 DOI: 10.3390/v5112856] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Revised: 11/13/2013] [Accepted: 11/14/2013] [Indexed: 12/21/2022] Open
Abstract
West Nile virus (WNV) is a neurotropic flavivirus that cycles between mosquitoes and birds but that can also infect humans, horses, and other vertebrate animals. In most humans, WNV infection remains subclinical. However, 20%-40% of those infected may develop WNV disease, with symptoms ranging from fever to meningoencephalitis. A large variety of WNV strains have been described worldwide. Based on their genetic differences, they have been classified into eight lineages; the pathogenic strains belong to lineages 1 and 2. Ten years ago, Beasley et al. (2002) found that dramatic differences exist in the virulence and neuroinvasion properties of lineage 1 and lineage 2 WNV strains. Further insights on how WNV interacts with its hosts have recently been gained; the virus acts either at the periphery or on the central nervous system (CNS), and these observed differences could help explain the differential virulence and neurovirulence of WNV strains. This review aims to summarize the current state of knowledge on factors that trigger WNV dissemination and CNS invasion as well as on the inflammatory response and CNS damage induced by WNV. Moreover, we will discuss how WNV strains differentially interact with the innate immune system and CNS cells, thus influencing WNV pathogenesis.
Collapse
Affiliation(s)
- Emilie Donadieu
- Université Paris Est Créteil (UPEC), UMR 1161 Virologie, Institut National de la Recherche Agronomique (INRA), Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail (ANSES) , Ecole Nationale Vétérinaire d'Alfort (ENVA), 7 avenue du Général De Gaulle, Maisons-Alfort 94700, France.
| | | | | | | | | | | |
Collapse
|
37
|
Death receptor-mediated apoptotic signaling is activated in the brain following infection with West Nile virus in the absence of a peripheral immune response. J Virol 2013; 88:1080-9. [PMID: 24198425 DOI: 10.1128/jvi.02944-13] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Apoptosis is an important mechanism of West Nile virus (WNV) pathogenesis within the central nervous system (CNS). The signaling pathways that result in WNV-induced apoptotic neuronal death within the CNS have not been established. In this study, we identified death receptor (DR)-induced apoptosis as a pathway that may be important in WNV pathogenesis, based on the pattern of differential gene expression in WNV-infected, compared to uninfected, brains. Reverse transcription-PCR (RT-PCR) and Western blotting confirmed that genes involved in DR-induced apoptotic signaling are upregulated in the brain following WNV infection. Activity of the DR-associated initiator caspase, caspase 8, was also increased in the brains of WNV-infected mice and occurred in association with cleavage of Bid and activation of caspase 9. These results demonstrate that DR-induced apoptotic signaling is activated in the brain following WNV infection and suggest that the caspase 8-dependent cleavage of Bid promotes intrinsic apoptotic signaling within the brains of infected animals. Utilization of a novel ex vivo brain slice culture (BSC) model of WNV encephalitis revealed that inhibition of caspase 8 decreases virus-induced activation of caspase 3 and tissue injury. The BSC model allows us to examine WNV-induced pathogenesis in the absence of a peripheral immune response. Thus, our results indicate that WNV-induced neuronal injury in the brain is mediated by DR-induced apoptosis signaling and can occur in the absence of infiltrating immune cells. However, astrocytes and microglia were activated in WNV-infected BSC, suggesting that local immune responses influence WNV pathogenesis.
Collapse
|
38
|
Dengue virus subgenomic RNA induces apoptosis through the Bcl-2-mediated PI3k/Akt signaling pathway. Virology 2013; 448:15-25. [PMID: 24314632 DOI: 10.1016/j.virol.2013.09.016] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 07/22/2013] [Accepted: 09/18/2013] [Indexed: 01/21/2023]
Abstract
We report a RNA species of 429 nucleotides derived from the 3' untranslated region of the viral genome in Dengue 2 virus (DENV-2) infected cells. The 3' terminal of viral RNA contained specific conserved structures that are important for the production of subgenomic RNA. Transient replicon assays suggested that loss of this small RNA has little effect on viral replication, and genetic analysis using recombinant viruses demonstrated that the existence of this subgenomic RNA is not essential for the life cycle of the DENV-2. Results from cytotoxicity and apoptosis assay revealed that the generation of subgenomic RNA is significant for DENV-2 viral cytopathicity and virus-induced apoptosis; and the deficiency could be partially restored by providing subgenomic RNA in trans from transfection. In addition, we found that subgenomic RNA modulates the phosphatidylinositol 3-kinase (PI3k)/Akt signaling pathway through a Bcl-2-related mechanism, resulting in apoptotic cell death.
Collapse
|
39
|
Yiang GT, Chen YH, Chou PL, Chang WJ, Wei CW, Yu YL. The NS3 protease and helicase domains of Japanese encephalitis virus trigger cell death via caspase‑dependent and ‑independent pathways. Mol Med Rep 2013; 7:826-30. [PMID: 23291778 DOI: 10.3892/mmr.2013.1261] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Accepted: 12/04/2012] [Indexed: 11/06/2022] Open
Abstract
Japanese encephalitis virus (JEV), a mosquito‑borne flavivirus, causes acute encephalitis and nervous damage. Previous studies have demonstrated that JEV induces apoptosis in infected cells. However, to date the mechanisms of JEV‑induced apoptosis are unclear. In order to identify the viral proteins associated with JEV‑induced apoptosis, pEGFP‑non‑structural protein 3 (NS3) 1‑619 (expressing the JEV NS3 intact protein, including the protease and helicase domains), pEGFP‑NS3 1‑180 (expressing the protease domain) and pEGFP‑NS3 163‑619 (expressing the helicase domain) were transfected into target cells to study cell death. Results demonstrate that the JEV NS3 intact protein and protease and helicase domains induce cell death. In addition, cell death was identified to be significantly higher in cells transfected with the NS3 protease domain compared with the intact protein and helicase domain. Caspase activation was also analyzed in the current study. NS3 intact protein and NS3 protease and helicase domains activated caspase‑9/‑3‑dependent and ‑independent pathways. However, caspase‑8 activity was not found to be significantly different in NS3‑transfected cells compared with control. In summary, the present study demonstrates that the NS3 helicase and protease domains of JEV activate caspase‑9/‑3‑dependent and ‑independent cascades and trigger cell death.
Collapse
Affiliation(s)
- Giou-Teng Yiang
- Department of Emergency Medicine, Tzu Chi University, Hualien 970, Taiwan, ROC
| | | | | | | | | | | |
Collapse
|
40
|
Immune responses to West Nile virus infection in the central nervous system. Viruses 2012; 4:3812-30. [PMID: 23247502 PMCID: PMC3528292 DOI: 10.3390/v4123812] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Revised: 12/07/2012] [Accepted: 12/10/2012] [Indexed: 12/16/2022] Open
Abstract
West Nile virus (WNV) continues to cause outbreaks of severe neuroinvasive disease in humans and other vertebrate animals in the United States, Europe, and other regions of the world. This review discusses our understanding of the interactions between virus and host that occur in the central nervous system (CNS), the outcome of which can be protection, viral pathogenesis, or immunopathogenesis. We will focus on defining the current state of knowledge of WNV entry, tropism, and host immune response in the CNS, all of which affect the balance between injury and successful clearance.
Collapse
|
41
|
Choksupmanee O, Hodge K, Katzenmeier G, Chimnaronk S. Structural Platform for the Autolytic Activity of an Intact NS2B–NS3 Protease Complex from Dengue Virus. Biochemistry 2012; 51:2840-51. [DOI: 10.1021/bi2018267] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Opas Choksupmanee
- Institute
of Molecular Biosciences, Mahidol University, Salaya Campus, Phutthamonthon, Thailand
73170
| | - Kenneth Hodge
- Institute
of Molecular Biosciences, Mahidol University, Salaya Campus, Phutthamonthon, Thailand
73170
| | - Gerd Katzenmeier
- Institute
of Molecular Biosciences, Mahidol University, Salaya Campus, Phutthamonthon, Thailand
73170
| | - Sarin Chimnaronk
- Institute
of Molecular Biosciences, Mahidol University, Salaya Campus, Phutthamonthon, Thailand
73170
| |
Collapse
|
42
|
Induction of the cellular microRNA, Hs_154, by West Nile virus contributes to virus-mediated apoptosis through repression of antiapoptotic factors. J Virol 2012; 86:5278-87. [PMID: 22345437 DOI: 10.1128/jvi.06883-11] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
MicroRNAs (miRNAs) are a class of noncoding small RNAs that regulate multiple cellular processes, as well as the replication and pathogenesis of many DNA viruses and some RNA viruses. Examination of cellular miRNA profiles in West Nile virus (WNV)-infected HEK293 and SK-N-MC cells revealed increased expression of multiple miRNA species. One of these miRNAs, Hs_154, was significantly induced not only in WNV-infected neuronal cells in culture but also in the central nervous system tissues of infected mice and, upon transfection, caused a significant reduction in viral replication. Analysis of mRNA transcripts enriched through immunoprecipitation of the RNA-induced silencing complex identified several transcripts that contain seed sequence matches to Hs_154 in their 3' untranslated regions (UTRs). Two of these targets, the CCCTC-binding factor (CTCF) and the epidermal growth factor receptor (EGFR)-coamplified and overexpressed protein (ECOP/VOPP1) proteins display reduced expression in WNV-infected cells, and the 3' UTRs of these transcripts were sufficient to cause downregulation of expression in infected cells or in cells transfected with Hs_154, findings consistent with miRNA targeting of these transcripts. CTCF and ECOP have been shown to be associated with cell survival, implicating miRNA-directed repression of these targets in WNV-induced cell death. Consistent with this hypothesis, expression of these genes in WNV-infected cells results in a reduction in the number of cells undergoing apoptosis. These observations suggest that induction of Hs_154 expression after WNV infection modulates the apoptotic response to WNV and that cellular miRNA expression can be quickly altered during WNV infection to control aspects of the host response.
Collapse
|
43
|
Li J, Huang R, Liao W, Chen Z, Zhang S, Huang R. Dengue virus utilizes calcium modulating cyclophilin-binding ligand to subvert apoptosis. Biochem Biophys Res Commun 2012; 418:622-7. [DOI: 10.1016/j.bbrc.2012.01.050] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Accepted: 01/10/2012] [Indexed: 12/16/2022]
|
44
|
Kobayashi S, Orba Y, Yamaguchi H, Kimura T, Sawa H. Accumulation of ubiquitinated proteins is related to West Nile virus-induced neuronal apoptosis. Neuropathology 2011; 32:398-405. [PMID: 22129084 DOI: 10.1111/j.1440-1789.2011.01275.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
West Nile virus (WNV) belongs to the Flaviviridae family of viruses and has emerged as a significant cause of viral encephalitis in humans, animals and birds. It has been reported that WNV replication directly induces neuronal injury, followed by neuronal cell death proven as apoptosis. Therefore, it is important to understand the mechanism of neuronal apoptosis caused by this virus to develop strategies to control its pathogenicity. Accumulation of ubiquitinated abnormal proteins has been reported to be associated with neuronal apoptosis in some pathological conditions. A lot of cellular stresses prevent cellular protein quality control mechanisms, resulting in the accumulation of ubiquitinated abnormal proteins. To obtain a better understanding of the mechanisms of WNV-induced neuronal apoptosis, we evaluated the accumulation of ubiquitinated proteins in the WNV-infected neuronal cells. We have observed that WNV infection caused massive neuronal injury in the brains of mice. Viral antigen was detected in the neuronal cytoplasm of the cells exhibiting neuronal apoptosis. Notably, ubiquitinated proteins were detected in WNV-infected neuronal cells. In addition, accumulation of ubiquitinated proteins was markedly enhanced in mouse neuroblastoma, Neuro-2a cells after WNV infection. Our histopathological and in vitro studies suggest that accumulation of ubiquitinated proteins in neuronal cells might be associated with neuronal apoptosis caused by WNV infection.
Collapse
Affiliation(s)
- Shintaro Kobayashi
- Division of Molecular Pathobiology, Hokkaido University Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | | | | | | | | |
Collapse
|
45
|
Doolittle JM, Gomez SM. Mapping protein interactions between Dengue virus and its human and insect hosts. PLoS Negl Trop Dis 2011; 5:e954. [PMID: 21358811 PMCID: PMC3039688 DOI: 10.1371/journal.pntd.0000954] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Accepted: 01/06/2011] [Indexed: 11/18/2022] Open
Abstract
Background Dengue fever is an increasingly significant arthropod-borne viral disease, with at least 50 million cases per year worldwide. As with other viral pathogens, dengue virus is dependent on its host to perform the bulk of functions necessary for viral survival and replication. To be successful, dengue must manipulate host cell biological processes towards its own ends, while avoiding elimination by the immune system. Protein-protein interactions between the virus and its host are one avenue through which dengue can connect and exploit these host cellular pathways and processes. Methodology/Principal Findings We implemented a computational approach to predict interactions between Dengue virus (DENV) and both of its hosts, Homo sapiens and the insect vector Aedes aegypti. Our approach is based on structural similarity between DENV and host proteins and incorporates knowledge from the literature to further support a subset of the predictions. We predict over 4,000 interactions between DENV and humans, as well as 176 interactions between DENV and A. aegypti. Additional filtering based on shared Gene Ontology cellular component annotation reduced the number of predictions to approximately 2,000 for humans and 18 for A. aegypti. Of 19 experimentally validated interactions between DENV and humans extracted from the literature, this method was able to predict nearly half (9). Additional predictions suggest specific interactions between virus and host proteins relevant to interferon signaling, transcriptional regulation, stress, and the unfolded protein response. Conclusions/Significance Dengue virus manipulates cellular processes to its advantage through specific interactions with the host's protein interaction network. The interaction networks presented here provide a set of hypothesis for further experimental investigation into the DENV life cycle as well as potential therapeutic targets. Dengue virus (DENV) represents a major disease burden in tropical and subtropical regions of the world, and has shown an increase in the number of cases in recent years. DENV is transmitted to humans through the bite of an infected mosquito, typically Aedes aegypti, after which it begins the infection and replication lifecycle within human cells. To perform the molecular functions required for invasion, replication, and spread of the virus, proteins encoded by DENV must interact with and alter the behavior of protein networks in both of these hosts. In this work, we used a computational method based on protein structures to predict interactions between DENV and its human and insect hosts. We predict numerous interactions, with many involved in known cell death, stress, and immune system pathways. Further investigation of these predicted protein-protein interactions should provide targets to combat the clinical manifestations of this disease in humans as well as points of intervention focused within the mosquito vector.
Collapse
Affiliation(s)
- Janet M. Doolittle
- Curriculum in Bioinformatics and Computational Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Shawn M. Gomez
- Joint Department of Biomedical Engineering, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
- Department of Computer Science, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
- * E-mail:
| |
Collapse
|
46
|
Inhibition of the type I interferon response in human dendritic cells by dengue virus infection requires a catalytically active NS2B3 complex. J Virol 2010; 84:9760-74. [PMID: 20660196 DOI: 10.1128/jvi.01051-10] [Citation(s) in RCA: 114] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Dengue virus (DENV) is the most prevalent arthropod-borne human virus, able to infect and replicate in human dendritic cells (DCs), inducing their activation and the production of proinflammatory cytokines. However, DENV can successfully evade the immune response in order to produce disease in humans. Several mechanisms of immune evasion have been suggested for DENV, most of them involving interference with type I interferon (IFN) signaling. We recently reported that DENV infection of human DCs does not induce type I IFN production by those infected DCs, impairing their ability to prime naive T cells toward Th1 immunity. In this article, we report that DENV also reduces the ability of DCs to produce type I IFN in response to several inducers, such as infection with other viruses or exposure to Toll-like receptor (TLR) ligands, indicating that DENV antagonizes the type I IFN production pathway in human DCs. DENV-infected human DCs showed a reduced type I IFN response to Newcastle disease virus (NDV), Sendai virus (SeV), and Semliki Forest virus (SFV) infection and to the TLR3 agonist poly(I:C). This inhibitory effect is DENV dose dependent, requires DENV replication, and takes place in DENV-infected DCs as early as 2 h after infection. Expressing individual proteins of DENV in the presence of an IFN-alpha/beta production inducer reveals that a catalytically active viral protease complex is required to reduce type I IFN production significantly. These results provide a new mechanism by which DENV evades the immune system in humans.
Collapse
|
47
|
Zhang B, Patel J, Croyle M, Diamond MS, Klein RS. TNF-alpha-dependent regulation of CXCR3 expression modulates neuronal survival during West Nile virus encephalitis. J Neuroimmunol 2010; 224:28-38. [PMID: 20579746 DOI: 10.1016/j.jneuroim.2010.05.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2010] [Accepted: 05/04/2010] [Indexed: 12/17/2022]
Abstract
The chemokine CXCL10 exerts antiviral effects within the central nervous system (CNS) through the recruitment of virus-specific T cells. However, elevated levels of CXCL10 may induce neuronal apoptosis given its receptor, CXCR3, is expressed by neurons. Using a murine model of West Nile virus (WNV) encephalitis, we determined that WNV-infected neurons express TNF-alpha, which down-regulates neuronal CXCR3 expression via signaling through TNFR1. Down-regulation of neuronal CXCR3 decreased CXCL10-mediated calcium transients and delayed Caspase 3 activation. Loss of CXCR3 activation, via CXCR3-deficiency or pretreatment with TNF-alpha prevented neuronal apoptosis during in vitro WNV infection. These results suggest that neuronal TNF-alpha expression during WNV encephalitis may be an adaptive response to diminish CXCL10-induced death.
Collapse
Affiliation(s)
- Bo Zhang
- Division of Infectious Diseases, Washington University School of Medicine, St. Louis, MO 63110, USA
| | | | | | | | | |
Collapse
|
48
|
Pastorino B, Nougairède A, Wurtz N, Gould E, de Lamballerie X. Role of host cell factors in flavivirus infection: Implications for pathogenesis and development of antiviral drugs. Antiviral Res 2010; 87:281-94. [PMID: 20452379 DOI: 10.1016/j.antiviral.2010.04.014] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2010] [Revised: 04/21/2010] [Accepted: 04/30/2010] [Indexed: 01/19/2023]
Abstract
The genus Flavivirus contains approximately 70 arthropod-borne enveloped RNA viruses many of which cause severe human and in some cases, animal disease. They include dengue virus, yellow fever virus, West Nile virus, Japanese encephalitis virus, and tick-borne encephalitis virus. Hundreds of thousands of deaths due to flavivirus infections occur each year, many of which are unpreventable due to lack of availability of appropriate vaccines and/or antiviral drugs. Flaviviruses exploit the cytoplasmic cellular machinery to facilitate propagation of infectious progeny virions. They engage in dynamic and antagonistic interactions with host cell membranes and biochemical processes. Following infection, the cells initiate various antiviral strategies to counteract viral invasion. In its defense, the virus has alternative strategies to suppress these host responses to infection. The fine balance between these interactions determines the outcome of the viral infection and disease progression. Published studies have revealed specific effects of flaviviruses on cellular processes, but the underlying mechanisms that determine the specific cytopathogenetic changes induced by different flaviviruses have not, as yet, been elucidated. Independently of the suppression of the type I IFN response which has been described in detail elsewhere, this review focuses on recent discoveries relating to alterations of host metabolism following viral infection. Such studies may contribute to new approaches to antiviral drug development. The role of host cellular factors will be examined in the context of protection and/or pathogenesis resulting from flavivirus infection, with particular emphasis on West Nile virus and dengue virus.
Collapse
Affiliation(s)
- Boris Pastorino
- Unité des Virus Emergents, UMR190 "Emergence des pathologies virales" Université de la Méditerranée, Institut de Recherche pour le Développement, Faculté de Médecine, Marseille, France
| | | | | | | | | |
Collapse
|
49
|
MKRN1 induces degradation of West Nile virus capsid protein by functioning as an E3 ligase. J Virol 2010; 84:426-36. [PMID: 19846531 DOI: 10.1128/jvi.00725-09] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
West Nile virus capsid protein (WNVCp) displays pathogenic toxicity via the apoptotic pathway. However, a cellular mechanism protective against this toxic effect has not been observed so far. Here, we identified Makorin ring finger protein 1 (MKRN1) as a novel E3 ubiquitin ligase for WNVCp. The cytotoxic effects of WNVCp as well as its expression levels were inhibited in U2OS cells that stably expressed MKRN1. Immunoprecipitation analyses revealed an interaction between MKRN1 and WNVCp. Domain analysis indicated that the C terminus of MKRN1 and the N terminus of WNVCp were required for the interaction. MKRN1 could induce WNVCp ubiquitination and degradation in a proteasome-dependent manner. Interestingly, the WNVCp mutant with amino acids 1 to 105 deleted WNVCp was degraded by MKRN1, whereas the mutant with amino acids 1 to 90 deleted was not. When three lysine sites at positions 101, 103, and 104 of WNVCp were replaced with alanine, MKRN1-mediated ubiquitination and degradation of the mutant were significantly inhibited, suggesting that these sites are required for the ubiquitination. Finally, U2OS cell lines stably expressing MKRN1 were resistant to cytotoxic effects of WNV. In contrast, cells depleted of MKRN1 were more susceptible to WNVCp cytotoxicity. Confirming this, overexpression of MKRN1 significantly reduced, but depletion of MKRN1 increased, WNV proliferation in 293T cells. Taken together, our results suggest that MKRN1 can protect cells from WNV by inducing WNVCp degradation.
Collapse
|
50
|
Gamlen T, Richards KH, Mankouri J, Hudson L, McCauley J, Harris M, Macdonald A. Expression of the NS3 protease of cytopathogenic bovine viral diarrhea virus results in the induction of apoptosis but does not block activation of the beta interferon promoter. J Gen Virol 2009; 91:133-44. [PMID: 19793904 DOI: 10.1099/vir.0.016170-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Bovine viral diarrhea virus (BVDV; genus Pestivirus) can exist as two biotypes, cytopathogenic (CP) and non-cytopathogenic (NCP). The CP form differs from NCP by the continual expression of free non-structural protein 3 (NS3). CP BVDV infection of cultured cells induces apoptosis, whereas NCP BVDV infection has been reported to block the induction of beta interferon (IFN-beta). To investigate the viral mechanisms underlying these effects, NS3 or NS2-3 proteins of NCP and CP BVDV biotypes, together with the cognate NS3 co-factor NS4A, were expressed in cells, and their effect on apoptosis and induction of IFN-beta was investigated. Expression of NS3/4A resulted in increased activity of caspase-9 and caspase-3, indicating induction of the intrinsic apoptosis pathway. Mutational analysis revealed that a protease-inactive NS3/4A was unable to induce apoptosis, suggesting that NS3 protease activity is required for initiation of apoptosis during CP BVDV infection. The ability of NS2-3 to modulate activation of the IFN-beta promoter was also investigated. These studies confirmed that, unlike the related hepatitis C virus and GB virus-B, BVDV proteases are unable to inhibit TLR3- and RIG-I-dependent activation of the IFN-beta promoter. These data suggest that BVDV NS3/4A is responsible for regulating the levels of cellular apoptosis and provide new insights regarding the viral elements associated with CP biotype pathogenesis.
Collapse
Affiliation(s)
- Toby Gamlen
- Institute of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
| | | | | | | | | | | | | |
Collapse
|