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Hu Y, Wu G, Jia Q, Zhang B, Sun W, Sa R, Zhang S, Cai W, Jarhen, Ran D, Liu J. Development of a live attenuated vaccine candidate for equid alphaherpesvirus 1 control: a step towards efficient protection. Front Immunol 2024; 15:1408510. [PMID: 39021566 PMCID: PMC11252532 DOI: 10.3389/fimmu.2024.1408510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Accepted: 06/11/2024] [Indexed: 07/20/2024] Open
Abstract
Equid alphaherpesvirus 1 (EqAHV1) is a viral pathogen known to cause respiratory disease, neurologic syndromes, and abortion storms in horses. Currently, there are no vaccines that provide complete protection against EqAHV1. Marker vaccines and the differentiation of infected and vaccinated animals (DIVA) strategy are effective for preventing and controlling outbreaks but have not been used for the prevention of EqAHV1 infection. Glycoprotein 2 (gp2), located on the envelope of viruses (EqAHV1), exhibits high antigenicity and functions as a molecular marker for DIVA. In this study, a series of EqAHV1 mutants with deletion of gp2 along with other virulence genes (TK, UL24/TK, gI/gE) were engineered. The mutant viruses were studied in vitro and then in an in vivo experiment using Golden Syrian hamsters to assess the extent of viral attenuation and the immune response elicited by the mutant viruses in comparison to the wild-type (WT) virus. Compared with the WT strain, the YM2019 Δgp2, ΔTK/gp2, and ΔUL24/TK/gp2 strains exhibited reduced growth in RK-13 cells, while the ΔgI/gE/gp2 strain exhibited significantly impaired proliferation. The YM2019 Δgp2 strain induced clinical signs and mortality in hamsters. In contrast, the YM2019 ΔTK/gp2 and ΔUL24/TK/gp2 variants displayed diminished pathogenicity, causing no observable clinical signs or fatalities. Immunization with nasal vaccines containing YM2019 ΔTK/gp2 and ΔUL24/TK/gp2 elicited a robust immune response in hamsters. In particular, compared with the vaccine containing the ΔTK/gp2 strain, the vaccine containing the ΔUL24/TK/gp2 strain demonstrated enhanced immune protection upon challenge with the WT virus. Furthermore, an ELISA for gp2 was established and refined to accurately differentiate between infected and vaccinated animals. These results confirm that the ΔUL24/TK/gp2 strain is a safe and effective live attenuated vaccine candidate for controlling EqAHV1 infection.
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Affiliation(s)
- Yue Hu
- Laboratory of Animal Infectious Disease, College of Veterinary Medicine, Xinjiang Agricultural University, Urumqi, Xinjiang Uygur Autonomous Region, China
- Chinese Academy of Sciences (CAS) Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Guiling Wu
- Preventive Control Section, Aksu Regional Animal Disease Control and Diagnostic Center, Aksu, Xinjiang Uygur Autonomous Region, China
| | - Qinrui Jia
- Laboratory of Animal Infectious Disease, College of Veterinary Medicine, Xinjiang Agricultural University, Urumqi, Xinjiang Uygur Autonomous Region, China
| | - Baozhong Zhang
- Chinese Academy of Sciences (CAS) Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Wencheng Sun
- Food, Agricultural and Health Products Division, Centre Testing International Group Co., Ltd., Qingdao, Shandong, China
| | - Ruixue Sa
- Laboratory of Animal Infectious Disease, College of Veterinary Medicine, Xinjiang Agricultural University, Urumqi, Xinjiang Uygur Autonomous Region, China
| | - Siyu Zhang
- Laboratory of Animal Infectious Disease, College of Veterinary Medicine, Xinjiang Agricultural University, Urumqi, Xinjiang Uygur Autonomous Region, China
| | - Weifan Cai
- Product Manufacturing Sector, GemPharmatech Co., Ltd., Shanghai, China
| | - Jarhen
- Laboratory of Animal Infectious Disease, College of Veterinary Medicine, Xinjiang Agricultural University, Urumqi, Xinjiang Uygur Autonomous Region, China
| | - Duoliang Ran
- Laboratory of Animal Infectious Disease, College of Veterinary Medicine, Xinjiang Agricultural University, Urumqi, Xinjiang Uygur Autonomous Region, China
| | - Jianhua Liu
- Laboratory of Animal Infectious Disease, College of Veterinary Medicine, Xinjiang Agricultural University, Urumqi, Xinjiang Uygur Autonomous Region, China
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Kasem S, Abdel-Moneim AS, Fukushi H. Establishment of a new equine embryo brain primary cell culture with long-term expansion. J Virol Methods 2024; 328:114952. [PMID: 38754768 DOI: 10.1016/j.jviromet.2024.114952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2024] [Revised: 05/10/2024] [Accepted: 05/11/2024] [Indexed: 05/18/2024]
Abstract
Primary cell cultures derived from human embryo lung play a crucial role in virology by aiding virus propagation and vaccine development. These cultures exhibit a notable ability to undergo multiple subcultures, often reaching up to 70 passages. However, finding alternative primary cell cultures with similar longevity and usefulness is challenging. In this study, we introduce a novel primary culture cells derived from equine embryo brain (FEB), which cells exhibited remarkable long-term cultivation potential. The FEB was established and maintained using Sumitomo Nerve-Cell Culture System Comparison studies were conducted with fetal equine kidney cell line (FEK-Tc13) to assess growth rates and subculture longevity. Immunological characterization was performed using neuronal markers to confirm the neural nature of FEB cells. Viral growth assessments were conducted using equine herpesviruses (EHV-1 and EHV-4) to evaluate infectivity and cytopathic effects in FEB cells. PCR analysis and real-time PCR assays were employed to detect viral genomic DNA and transcription activity of EHVs in infected FEB cells. FEB cells demonstrated faster growth rates compared to fetal equine kidney cell line (FEK-Tc13 cells) and exhibited sustained subculture capability exceeding 50 passages. Immunostaining confirmed the glial identity of FEB cells. Both equine herpesviruses 1 and 4 EHV-1 and EHV-4 viruses efficiently replicated in FEB cells, resulting in clear cytopathic effects. PCR analysis detected genomic DNA of EHVs in infected FEB cells, indicating successful viral infection. The establishment of FEB cells with extended subculture capability highlights their potential utility as a model system for studying neural cell biology and viral infections.
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Affiliation(s)
- Samy Kasem
- Department of Virology, Faculty of Veterinary Medicine, Kafrelsheikh University, Kafrelsheikh 33516, Egypt; Laboratory of Veterinary Microbiology, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Ahmed S Abdel-Moneim
- Department of Microbiology, College of Medicine, Taif University Al-Taif 21944, Saudi Arabia.
| | - Hideto Fukushi
- Laboratory of Veterinary Microbiology, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
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Eady NA, Holmes C, Schnabel C, Babasyan S, Wagner B. Equine herpesvirus type 1 (EHV-1) replication at the upper respiratory entry site is inhibited by neutralizing EHV-1-specific IgG1 and IgG4/7 mucosal antibodies. J Virol 2024; 98:e0025024. [PMID: 38742875 PMCID: PMC11237562 DOI: 10.1128/jvi.00250-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Accepted: 04/11/2024] [Indexed: 05/16/2024] Open
Abstract
Equine herpesvirus type 1 (EHV-1) is a contagious respiratory pathogen that infects the mucosa of the upper respiratory tract (URT). Mucosal immune responses at the URT provide the first line of defense against EHV-1 and are crucial for orchestrating immunity. To define host-pathogen interactions, we characterized B-cell responses, antibody isotype functions, and EHV-1 replication of susceptible (non-immune) and clinically protected (immune) horses after experimental EHV-1 infection. Nasal secretion and nasal wash samples were collected and used for the isolation of DNA, RNA, and mucosal antibodies. Shedding of infectious virus, EHV-1 copy numbers, viral RNA expression, and host B-cell activation in the URT were compared based on host immune status. Mucosal EHV-1-specific antibody responses were associated with EHV-1 shedding and viral RNA transcription. Finally, mucosal immunoglobulin G (IgG) and IgA isotypes were purified and tested for neutralizing capabilities. IgG1 and IgG4/7 neutralized EHV-1, while IgG3/5, IgG6, and IgA did not. Immune horses secreted high amounts of mucosal EHV-1-specific IgG4/7 antibodies and quickly upregulated B-cell pathway genes, while EHV-1 was undetected by virus isolation and PCR. RNA transcription analysis reinforced incomplete viral replication in immune horses. In contrast, complete viral replication with high viral copy numbers and shedding of infectious viruses was characteristic for non-immune horses, together with low or absent EHV-1-specific neutralizing antibodies during viral replication. These data confirm that pre-existing mucosal IgG1 and IgG4/7 and rapid B-cell activation upon EHV-1 infection are essential for virus neutralization, regulation of viral replication, and mucosal immunity against EHV-1.IMPORTANCEEquine herpesvirus type 1 (EHV-1) causes respiratory disease, abortion storms, and neurologic outbreaks known as equine herpes myeloencephalopathy (EHM). EHV-1 is transmitted with respiratory secretions by nose-to-nose contact or via fomites. The virus initially infects the epithelium of the upper respiratory tract (URT). Host-pathogen interactions and mucosal immunity at the viral entry site provide the first line of defense against the EHV-1. Robust mucosal immunity can be essential in protecting against EHV-1 and to reduce EHM outbreaks. It has previously been shown that immune horses do not establish cell-associated viremia, the prerequisite for EHM. Here, we demonstrate how mucosal antibodies can prevent the replication of EHV-1 at the epithelium of the URT and, thereby, the progression of the virus to the peripheral blood. The findings improve the mechanistic understanding of mucosal immunity against EHV-1 and can support the development of enhanced diagnostic tools, vaccines against EHM, and the management of EHV-1 outbreaks.
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Affiliation(s)
- Naya A. Eady
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Camille Holmes
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Christiane Schnabel
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Susanna Babasyan
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Bettina Wagner
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
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Hassanien RT, Thieulent CJ, Carossino M, Li G, Balasuriya UBR. Modulation of Equid Herpesvirus-1 Replication Dynamics In Vitro Using CRISPR/Cas9-Assisted Genome Editing. Viruses 2024; 16:409. [PMID: 38543774 PMCID: PMC10975850 DOI: 10.3390/v16030409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 02/29/2024] [Accepted: 03/02/2024] [Indexed: 05/23/2024] Open
Abstract
(1) Background: equid alphaherpesvirus-1 (EHV-1) is a highly contagious viral pathogen prevalent in most horse populations worldwide. Genome-editing technologies such as CRISPR/Cas9 have become powerful tools for precise RNA-guided genome modifications; (2) Methods: we designed single guide RNAs (sgRNA) to target three essential (ORF30, ORF31, and ORF7) and one non-essential (ORF74) EHV-1 genes and determine their effect on viral replication dynamics in vitro; (3) Results: we demonstrated that sgRNAs targeting essential lytic genes reduced EHV-1 replication, whereas those targeting ORF74 had a negligible effect. The sgRNAs targeting ORF30 showed the strongest effect on the suppression of EHV-1 replication, with a reduction in viral genomic copy numbers and infectious progeny virus output. Next-generation sequencing identified variants with deletions in the specific cleavage site of selective sgRNAs. Moreover, we evaluated the combination between different sgRNAs and found that the dual combination of sgRNAs targeting ORF30 and ORF7 significantly suppressed viral replication to lower levels compared to the use of a single sgRNA, suggesting a synergic effect; (4) Conclusion: data demonstrate that sgRNA-guided CRISPR/Cas9 can be used to inhibit EHV-1 replication in vitro, indicating that this programmable technique can be used to develop a novel, safe, and efficacious therapeutic and prophylactic approach against EHV-1.
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Affiliation(s)
- Rabab T. Hassanien
- Louisiana Animal Disease Diagnostic Laboratory, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA; (R.T.H.); (C.J.T.); (M.C.)
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA
- Virology Department, Animal Health Research Institute, Agriculture Research Center (ARC), Dokki, Giza 12618, Egypt
| | - Côme J. Thieulent
- Louisiana Animal Disease Diagnostic Laboratory, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA; (R.T.H.); (C.J.T.); (M.C.)
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Mariano Carossino
- Louisiana Animal Disease Diagnostic Laboratory, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA; (R.T.H.); (C.J.T.); (M.C.)
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Ganwu Li
- Department of Veterinary Diagnostics and Production Animal Medicine, Iowa State University, Ames, IA 50011, USA;
| | - Udeni B. R. Balasuriya
- Louisiana Animal Disease Diagnostic Laboratory, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA; (R.T.H.); (C.J.T.); (M.C.)
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA
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Ruan P, Wang M, Cheng A, Zhao X, Yang Q, Wu Y, Zhang S, Tian B, Huang J, Ou X, Gao Q, Sun D, He Y, Wu Z, Zhu D, Jia R, Chen S, Liu M. Mechanism of herpesvirus UL24 protein regulating viral immune escape and virulence. Front Microbiol 2023; 14:1268429. [PMID: 37808279 PMCID: PMC10559885 DOI: 10.3389/fmicb.2023.1268429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 09/08/2023] [Indexed: 10/10/2023] Open
Abstract
Herpesviruses have evolved a series of abilities involved in the process of host infection that are conducive to virus survival and adaptation to the host, such as immune escape, latent infection, and induction of programmed cell death for sustainable infection. The herpesvirus gene UL24 encodes a highly conserved core protein that plays an important role in effective viral infection. The UL24 protein can inhibit the innate immune response of the host by acting on multiple immune signaling pathways during virus infection, and it also plays a key role in the proliferation and pathogenicity of the virus in the later stage of infection. This article reviews the mechanism by which the UL24 protein mediates herpesvirus immune escape and its effects on viral proliferation and virulence by influencing syncytial formation, DNA damage and the cell cycle. Reviewing these studies will enhance our understanding of the pathogenesis of herpesvirus infection and provide evidence for new strategies to combat against viral infection.
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Affiliation(s)
- Peilin Ruan
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Mingshu Wang
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Anchun Cheng
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Xinxin Zhao
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Qiao Yang
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Ying Wu
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Shaqiu Zhang
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Bin Tian
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Juan Huang
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Xumin Ou
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Qun Gao
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Di Sun
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Yu He
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Zhen Wu
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Dekang Zhu
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Renyong Jia
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Shun Chen
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Mafeng Liu
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
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Li Z, He Y, Ge L, Quan R, Chen J, Hu Y, Sa R, Liu J, Ran D, Fu Q, Shi H. Berbamine, a bioactive alkaloid, suppresses equine herpesvirus type 1 in vitro and in vivo. Front Vet Sci 2023; 10:1163780. [PMID: 37303732 PMCID: PMC10247970 DOI: 10.3389/fvets.2023.1163780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Accepted: 05/10/2023] [Indexed: 06/13/2023] Open
Abstract
Equine herpesvirus type 1 (EHV-1) poses a global threat to equines. The anticancer agent berbamine (BBM), a bioactive alkaloid, has been shown to inhibit viral infection. However, whether BBM can inhibit EHV-1 infection remains unclear. This study investigated the effect of BBM treatment on EHV-1 infection. Quantitative PCR (qPCR), immunoblotting, the Reed-Muench method, and pathological examination were employed to study the ability of BBM to inhibit EHV-1 infection, viral DNA replication, viral protein production, virion secretion, and cytopathogenesis in vitro and in vivo. The in vitro studies revealed that 10 μM BBM effectively suppressed EHV-1 viral entry into cells, viral DNA replication, and virion secretion, while the in vivo studies verified the ability of BBM to suppress EHV-1-induced damage of brain and lung tissues and animal mortality. These findings strongly suggest that BBM could be a serious contender in the therapeutic control of EHV-1 infection of equines.
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Hao M, Tang J, Ge S, Li T, Xia N. Bacterial-Artificial-Chromosome-Based Genome Editing Methods and the Applications in Herpesvirus Research. Microorganisms 2023; 11:microorganisms11030589. [PMID: 36985163 PMCID: PMC10056367 DOI: 10.3390/microorganisms11030589] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 02/21/2023] [Accepted: 02/23/2023] [Indexed: 03/02/2023] Open
Abstract
Herpesviruses are major pathogens that infect humans and animals. Manipulating the large genome is critical for exploring the function of specific genes and studying the pathogenesis of herpesviruses and developing novel anti-viral vaccines and therapeutics. Bacterial artificial chromosome (BAC) technology significantly advanced the capacity of herpesviruses researchers to manipulate the virus genomes. In the past years, advancements in BAC-based genome manipulating and screening strategies of recombinant BACs have been achieved, which has promoted the study of the herpes virus. This review summarizes the advances in BAC-based gene editing technology and selection strategies. The merits and drawbacks of BAC-based herpesvirus genome editing methods and the application of BAC-based genome manipulation in viral research are also discussed. This review provides references relevant for researchers in selecting gene editing methods in herpes virus research. Despite the achievements in the genome manipulation of the herpes viruses, the efficiency of BAC-based genome manipulation is still not satisfactory. This review also highlights the need for developing more efficient genome-manipulating methods for herpes viruses.
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Affiliation(s)
- Mengling Hao
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, Department of Laboratory Medicine, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Jiabao Tang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, Department of Laboratory Medicine, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Shengxiang Ge
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, Department of Laboratory Medicine, School of Public Health, Xiamen University, Xiamen 361102, China
- Xiang An Biomedicine Laboratory, Xiamen 361102, China
- NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Tingdong Li
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, Department of Laboratory Medicine, School of Public Health, Xiamen University, Xiamen 361102, China
- Xiang An Biomedicine Laboratory, Xiamen 361102, China
- NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, School of Public Health, Xiamen University, Xiamen 361102, China
- Correspondence:
| | - Ningshao Xia
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, Department of Laboratory Medicine, School of Public Health, Xiamen University, Xiamen 361102, China
- Xiang An Biomedicine Laboratory, Xiamen 361102, China
- NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, School of Public Health, Xiamen University, Xiamen 361102, China
- The Research Unit of Frontier Technology of Structural Vaccinology of Chinese Academy of Medical Sciences, Xiamen 361102, China
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Fukushi N, Badr Y, Fukushi H. The N-terminal glycine of EHV-1 UL11 is essential for the localization of UL11 and EHV-1 replication in cultured cells. J Gen Virol 2023; 104. [PMID: 36748631 DOI: 10.1099/jgv.0.001798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Equine herpesvirus type 1 (EHV-1) UL11 is a 74-amino-acid (aa) protein encoded by ORF51. UL11 is modified by acylation including myristoylation and palmitoylation. Myristoylation of EHV-1 UL11 is assumed to occur on the N-terminal glycine, while palmitoylation is assumed to occur on the seventh and ninth cysteines. ORF51, which encodes the first 24 aa, overlaps ORF50 encoding UL12. We previously demonstrated that UL11 was essential for EHV-1 replication in cultured cells and that UL11 was localized at the Golgi apparatus where herpesviruses obtain their final envelope. It is unclear whether the acylation is related to the localization of EHV-1 UL11 and viral replication. In this study, we investigated the role of UL11 acylation in the intracellular localization and viral growth and replication of EHV-1. We constructed seven UL11 acylation mutant plasmids and seven UL11 acylation mutant BAC DNAs; then, we analysed the localizations of the mutant UL11s and attempted virus rescue. We found that both the N-terminal glycine and the seventh or ninth cysteine, especially N-terminal glycine, were involved in the localization of UL11 and viral replication. Taken together, these results suggest that EHV-1 viral growth requires that UL11 is modified by myristoylation of an N-terminal glycine and by palmitoylation of at least one of the cysteines, and that UL11 is localized at the Golgi apparatus. This study shows that a single amino acid in EHV-1 can determine the fate of viral replication.
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Affiliation(s)
- Noriko Fukushi
- Department of Applied Veterinary Sciences, United Graduated School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Yassien Badr
- Department of Applied Veterinary Sciences, United Graduated School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan.,Department of Animal Medicine (Branch of Infectious Disease), Faculty of Veterinary Medicine, Damanhour University, El-Beheira 2251, Egypt
| | - Hideto Fukushi
- Department of Applied Veterinary Sciences, United Graduated School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan.,Laboratory of Veterinary Microbiology, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan.,Joint Graduate School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
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9
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Quentin-Froignant C, Kappler-Gratias S, Top S, Bertagnoli S, Gallardo F. ANCHOR-tagged equine herpesvirus 1: A new tool for monitoring viral infection and discovering new antiviral compounds. J Virol Methods 2021; 294:114194. [PMID: 34022301 DOI: 10.1016/j.jviromet.2021.114194] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 05/17/2021] [Accepted: 05/17/2021] [Indexed: 12/26/2022]
Abstract
Equine herpesvirus 1 (EHV-1) is a causative agent of respiratory disorders, abortion and myeloencephalopathy in horses and has an important impact on equine health and economy. Several bacterial artificial chromosomes have already been developed and enabled identification and functional characterization of EHV-1 genes. Unfortunately, little is known about its replication. Here, the ANCHOR system was inserted by targeted homologous recombination into the equine herpesvirus genome. This insertion led to the conversion of EHV-1 DNA to auto-fluorescent spots easily detectable by fluorescence microscopy, and enabled production of an auto-fluorescent EHV-1 ANCHORGFP with tropism and replication kinetic like the parental strain. High resolution imaging allowed first visualization of EHV-1 replication from apparition of first viral genome to large replicative centers, in single cells or inside syncytia. Combined with high content microscopy, EHV-1 ANCHORGFP leads to identification of auranofin and azacytidine-5 as new potential antivirals to treat EHV-1 infection.
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Affiliation(s)
- Charlotte Quentin-Froignant
- NeoVirTech SAS, Centre Pierre Potier, Toulouse, France; IHAP, Université de Toulouse, INRAE, ENVT, Toulouse, France.
| | | | - Sokunthea Top
- NeoVirTech SAS, Centre Pierre Potier, Toulouse, France.
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10
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Sutton G, Thieulent C, Fortier C, Hue ES, Marcillaud-Pitel C, Pléau A, Deslis A, Guitton E, Paillot R, Pronost S. Identification of a New Equid Herpesvirus 1 DNA Polymerase (ORF30) Genotype with the Isolation of a C 2254/H 752 Strain in French Horses Showing no Major Impact on the Strain Behaviour. Viruses 2020; 12:v12101160. [PMID: 33066315 PMCID: PMC7650556 DOI: 10.3390/v12101160] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 10/06/2020] [Accepted: 10/08/2020] [Indexed: 12/21/2022] Open
Abstract
Equid herpesvirus 1 is one of the most common viral pathogens in the horse population and is associated with respiratory disease, abortion and still-birth, neonatal death and neurological disease. A single point mutation in the DNA polymerase gene (ORF30: A2254G, N752D) has been widely associated with neuropathogenicity of strains, although this association has not been exclusive. This study describes the fortuitous isolation of a strain carrying a new genotype C2254 (H752) from an outbreak in France that lasted several weeks in 2018 and involved 82 horses, two of which showed neurological signs of disease. The strain was characterised as UL clade 10 using the equid herpesvirus 1 (EHV-1) multi-locus sequence typing (MLST) classification but has not been identified or isolated since 2018. The retrospective screening of EHV-1 strains collected between 2016 and 2018 did not reveal the presence of the C2254 mutation. When cultured in vitro, the C2254 EHV-1 strain induced a typical EHV-1 syncytium and cytopathic effect but no significant difference was observed when compared with A2254 and G2254 EHV-1 strains. An experimental infection was carried out on four Welsh mountain ponies to confirm the infectious nature of the C2254 strain. A rapid onset of marked respiratory disease lasting at least 2 weeks, with significant virus shedding and cell-associated viraemia, was observed. Finally, an in vitro antiviral assay using impedance measurement and viral load quantification was performed with three antiviral molecules (ganciclovir (GCV), aciclovir (ACV) and aphidicolin (APD)) on the newly isolated C2254 strain and two other A/G2254 field strains. The three strains showed similar sensitivity to ganciclovir and aphidicolin but both C2254 and A2254 strains were more sensitive to aciclovir than the G2254 strain, based on viral load measurement.
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Affiliation(s)
- Gabrielle Sutton
- LABÉO Frank Duncombe, 14280 Saint-Contest, France; (G.S.); (C.T.); (C.F.); (E.S.H.); (R.P.)
- BIOTARGEN, Normandie Univ, UNICAEN, 14000 Caen, France
| | - Côme Thieulent
- LABÉO Frank Duncombe, 14280 Saint-Contest, France; (G.S.); (C.T.); (C.F.); (E.S.H.); (R.P.)
- BIOTARGEN, Normandie Univ, UNICAEN, 14000 Caen, France
| | - Christine Fortier
- LABÉO Frank Duncombe, 14280 Saint-Contest, France; (G.S.); (C.T.); (C.F.); (E.S.H.); (R.P.)
- BIOTARGEN, Normandie Univ, UNICAEN, 14000 Caen, France
- ImpedanCELL, Normandie Univ, UNICAEN, 14280 Saint-Contest, France
| | - Erika S. Hue
- LABÉO Frank Duncombe, 14280 Saint-Contest, France; (G.S.); (C.T.); (C.F.); (E.S.H.); (R.P.)
- BIOTARGEN, Normandie Univ, UNICAEN, 14000 Caen, France
- ImpedanCELL, Normandie Univ, UNICAEN, 14280 Saint-Contest, France
| | | | - Alexis Pléau
- INRAE, UE-1277 Plateforme d’Infectiologie Expérimentale (PFIE), Centre de Recherche Val de Loire, 37380 Nouzilly, France; (A.P.); (A.D.); (E.G.)
| | - Alain Deslis
- INRAE, UE-1277 Plateforme d’Infectiologie Expérimentale (PFIE), Centre de Recherche Val de Loire, 37380 Nouzilly, France; (A.P.); (A.D.); (E.G.)
| | - Edouard Guitton
- INRAE, UE-1277 Plateforme d’Infectiologie Expérimentale (PFIE), Centre de Recherche Val de Loire, 37380 Nouzilly, France; (A.P.); (A.D.); (E.G.)
| | - Romain Paillot
- LABÉO Frank Duncombe, 14280 Saint-Contest, France; (G.S.); (C.T.); (C.F.); (E.S.H.); (R.P.)
- BIOTARGEN, Normandie Univ, UNICAEN, 14000 Caen, France
- School of Equine and Veterinary Physiotherapy, Writtle University College, Lordship Road, Writtle, Chelmsford CM1 3RR, UK
| | - Stéphane Pronost
- LABÉO Frank Duncombe, 14280 Saint-Contest, France; (G.S.); (C.T.); (C.F.); (E.S.H.); (R.P.)
- BIOTARGEN, Normandie Univ, UNICAEN, 14000 Caen, France
- ImpedanCELL, Normandie Univ, UNICAEN, 14280 Saint-Contest, France
- Correspondence: ; Tel.: +33-2-3147-1919
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11
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Saleh AG, El-Habashi N, Abd-Ellatieff HA, Abas OM, Anwar S, Fukushi H, Yanai T. Comparative Study of the Pathogenesis of Rhinopneumonitis Induced by Intranasal Inoculation of Hamsters with Equine Herpesvirus-9, Equine Herpesvirus-1 strain Ab4p and Zebra-borne Equine Herpesvirus-1. J Comp Pathol 2020; 180:35-45. [PMID: 33222872 DOI: 10.1016/j.jcpa.2020.08.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 06/25/2020] [Accepted: 08/03/2020] [Indexed: 10/23/2022]
Abstract
Equine herpesvirus-9 (EHV-9), equine herpesvirus-1 (EHV-1) and zebra-borne EHV-1 are members of the family Herpesviridae and cause encephalitis and rhinopneumonitis in a range of animal species. The aim of this study was to characterize and compare the rhinopneumonitis induced by experimental intranasal inoculation of groups of hamsters with EHV-9, EHV-1 strain Ab4p or zebra-borne EHV-1 viruses. Animals inoculated with EHV-9 had earlier and more severe neurological and respiratory signs than those inoculated with EHV-1 strain Ab4p or zebra-borne EHV-1. At 4-5 days post inoculation (dpi), hamsters inoculated with EHV-9 had significantly increased expression of open reading fame (ORF) 30, the viral gene encoding the DNA polymerase, in lung tissue. ORF 30 expression at these time points was higher in the hamsters infected with EHV-9 than in those inoculated with the other two viruses. Severe, mild or very mild rhinitis was seen in animals inoculated with EHV-1 strain Ab4p, EHV-9 and zebra-borne EHV-1, respectively. Viral antigen was detected in olfactory receptor neurons, inflammatory cells and desquamated epithelial cells in animals in all groups until 5 dpi. Tracheitis was also seen in all three virus-infected groups with viral antigen detected in tracheal epithelium. Inoculated hamsters developed interstitial pneumonia of increasing severity over the course of the experiment. Bronchopneumonia and vasculitis were also seen in all three infected groups. These results confirm that, in addition to their neurotropism, EHV-9 and zebra-borne EHV-1 are pneumotropic viruses. EHV-1 strain Ab4p caused more severe upper respiratory tract disease, but no significant differences were detected in the severity of pneumonia induced by each virus.
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Affiliation(s)
- Asmaa G Saleh
- Laboratory of Veterinary Pathology and Microbiology, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan; Department of Animal Medicine, Faculty of Veterinary Medicine, Damanhur University, El-Beheira
| | - Nagwan El-Habashi
- Department of Veterinary Pathology, Faculty of Veterinary Medicine, Kafrelsheikh University, Kafrelsheikh, Egypt
| | - Hoda A Abd-Ellatieff
- Department of Pathology and Clinical Pathology, Faculty of Veterinary Medicine, Damanhur University, El-Beheira, Egypt
| | - Osama M Abas
- Laboratory of Veterinary Microbiology, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan; Department of Animal Medicine, Faculty of Veterinary Medicine, Alexandria University, Alexandria Department of Pathology, Faculty of Veterinary Medicine, Beni-Suef University, Beni-Suef, Egypt
| | - Shehata Anwar
- Neuroscience Laboratory, CHU de Québec Research Centre, Department of Molecular Medicine, Faculty of Medicine, Laval University, Canada
| | - Hideto Fukushi
- Laboratory of Veterinary Pathology and Microbiology, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan
| | - Tokuma Yanai
- Laboratory of Veterinary Pathology and Microbiology, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan; Laboratory of Wildlife and Forensic Science, Faculty of Veterinary Medicine, Okayama University of Science, Imabari, Japan.
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12
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Ata EB, Salama A, Zaghawa A, Ghazy AA, Elsify A, Nayel M, Hegazy Y, Abdel-Rahman EH, Warda S. Seroprevalence of equine herpes virus-1 in endemic area of Egypt with risk factors assessment. BULGARIAN JOURNAL OF VETERINARY MEDICINE 2020. [DOI: 10.15547/bjvm.2168] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Although equine herpesvirus-1 (EHV-1) infection occurs throughout the world; causing various health problems within horse population such as respiratory disease, abortion and myeloencephalopathy, there is information shortage concerning the epidemiological situation of EHVs in Egypt. This paper is the first study of EHV-1 prevalence rate in Monufia province (as a model for other provinces). During 2015, two hundred and seventy serum samples from EHV non-vaccinated horses were randomly collected from 9 centres of Monufia province. The indirect ELISA was used to detect the prevalence rate of the disease while assessment of the associated risk factors was conducted using univariate and multivariate logistic regression models. The results showed that EHV-1 infection was widespread among horses at Monufia province (apparent prevalence rate 64% and true prevalence rate 28%) and posed risk for the health of other equines in the region. Results of risk factors identification showed that horses > 5 years of age were at significant risk of getting EHV-1 infection than < 1-year-old horses (OR: 5; P<0.02), while males were twice more prone than females of getting the EHV-1 infection (OR: 2 and P<0.03). There was a significant effect of different localities on the prevalence of EHV-1 infection. The obtained results could be extrapolated to the different districts and governorates of Egypt because of the similarity of the husbandry system of equines all over Egypt.
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Oladunni FS, Horohov DW, Chambers TM. EHV-1: A Constant Threat to the Horse Industry. Front Microbiol 2019; 10:2668. [PMID: 31849857 PMCID: PMC6901505 DOI: 10.3389/fmicb.2019.02668] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Accepted: 11/01/2019] [Indexed: 12/17/2022] Open
Abstract
Equine herpesvirus-1 (EHV-1) is one of the most important and prevalent viral pathogens of horses and a major threat to the equine industry throughout most of the world. EHV-1 primarily causes respiratory disease but viral spread to distant organs enables the development of more severe sequelae; abortion and neurologic disease. The virus can also undergo latency during which viral genes are minimally expressed, and reactivate to produce lytic infection at any time. Recently, there has been a trend of increasing numbers of outbreaks of a devastating form of EHV-1, equine herpesviral myeloencephalopathy. This review presents detailed information on EHV-1, from the discovery of the virus to latest developments on treatment and control of the diseases it causes. We also provide updates on recent EHV-1 research with particular emphasis on viral biology which enables pathogenesis in the natural host. The information presented herein will be useful in understanding EHV-1 and formulating policies that would help limit the spread of EHV-1 within horse populations.
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Affiliation(s)
- Fatai S. Oladunni
- Maxwell H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, United States
- Department of Veterinary Microbiology, University of Ilorin, Ilorin, Nigeria
| | - David W. Horohov
- Maxwell H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, United States
| | - Thomas M. Chambers
- Maxwell H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, United States
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14
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Ye C, Chen J, Cheng X, Zhou S, Jiang S, Xu J, Zheng H, Tong W, Li G, Tong G. Functional analysis of the UL24 protein of suid herpesvirus 1. Virus Genes 2019; 55:76-86. [PMID: 30478778 DOI: 10.1007/s11262-018-1619-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 11/23/2018] [Indexed: 11/28/2022]
Abstract
The UL24 homologous genes are conserved in alphaherpesviruses. However, the proximity of the UL24 gene and the UL23 gene encoding for thymidine kinase (TK) in the genome of suid herpesvirus 1 (SuHV-1) makes it difficult to mutate UL24 without affecting the expression of the TK gene, and thus functional studies of the UL24 gene have lagged behind. In this study, CRISPR/Cas9 and homologous recombination were adopted to generate UL24 and TK mutant viruses. Deletion of either the UL24 or the TK gene resulted in significantly reduced SuHV-1 replication and spread capacity in Vero cells. However, UL24-deleted virus still maintained a certain degree of lethality in mice, while TK-deleted viruses completely lost their lethality in mice. Similarly, neurovirulence of UL24-deleted virus in mice was not significantly affected compared to parental virus. In comparison, infection with the TK-deleted viruses resulted in significantly reduced neurovirulence and complete loss of lethality. In addition, and for the first time, viral UL24 protein was found to be expressed late during SuHV-1 infection; enhanced green fluorescence protein (eGFP) labeled UL24 protein was shown to be localized in the nucleus via heterologous expression. In conclusion, the UL24 gene of SuHV-1 encodes a nuclear-localized viral protein and acts as a minor virulence-associated factor compared to the TK gene.
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Affiliation(s)
- Chao Ye
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 518, Ziyue Road, Minhang District, Shanghai, 200241, China
| | - Jing Chen
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 518, Ziyue Road, Minhang District, Shanghai, 200241, China
| | - Xuefei Cheng
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 518, Ziyue Road, Minhang District, Shanghai, 200241, China
| | - Shasha Zhou
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 518, Ziyue Road, Minhang District, Shanghai, 200241, China
| | - Shan Jiang
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 518, Ziyue Road, Minhang District, Shanghai, 200241, China
| | - Jingjing Xu
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 518, Ziyue Road, Minhang District, Shanghai, 200241, China
| | - Hao Zheng
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 518, Ziyue Road, Minhang District, Shanghai, 200241, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, Jiangsu, China
| | - Wu Tong
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 518, Ziyue Road, Minhang District, Shanghai, 200241, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, Jiangsu, China
| | - Guoxin Li
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 518, Ziyue Road, Minhang District, Shanghai, 200241, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, Jiangsu, China
| | - Guangzhi Tong
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 518, Ziyue Road, Minhang District, Shanghai, 200241, China.
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, Jiangsu, China.
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Ata EB, Zaghawa A, Ghazy AA, Elsify A, Abdelrahman K, Kasem S, Nayel M. Development and characterization of ORF68 negative equine herpes virus type-1, Ab4p strain. J Virol Methods 2018; 261:121-131. [PMID: 30165189 DOI: 10.1016/j.jviromet.2018.08.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Revised: 08/25/2018] [Accepted: 08/26/2018] [Indexed: 01/20/2023]
Abstract
Equine herpesvirus-1 (EHV-1) is an important pathogen, which infects horses worldwide with high morbidity but low mortality rates. The respiratory disorders and abortions are the most common indicators. Ab4p (an abortigenic and paralytic virus) is one of the most important and virulent strains. The development and functional characterization of the open reading frame-68 (ORF68) negative EHV-1 Ab4p mutants and an assessment of their roles in the infection at the cellular level were the main targets of the current study. Escherichia coli DH10β containing the Ab4p bacterial artificial chromosome (pAb4pBAC) and Red/ET expression vector were used to develop different ORF68 mutants. Multi-step growth kinetic experiments were conducted in order to evaluate the growth properties of the constructed mutant viruses. Growth of the Ab4pΔORF68 showed the lowest titer, compared to the Ab4pΔORF68R, Ab4pΔORF68R non-sense, and the parent Ab4p viruses without any significant difference (P > 0.05). The growth of the mutant viruses was almost similar across the cell types, but viruses growth was more efficient in FHK cells as judged by the number of the obtained virus particles. The plaque size of Ab4pΔORF68 was significantly (40%) smaller than those of Ab4p (P < 0.01), Ab4pΔORF68R, and Ab4pΔORF68R non-sense viruses which confirmed the importance of ORF68 protein in the cell-to-cell transmission of EHV-1. Subcellular localization of the green fluorescent protein (GFP) ORF68 gene fusion product showed late expression with intranuclear localization of the transfected cells while immunofluorescent antibody technique (IFAT) localized it at the nucleus and nuclear membranes of the infected cells. Hence, it could be concluded that ORF68 protein may not be essential for EHV-1 Ab4p growth but plays a crucial role in virus penetration and transmission at the cellular level. Therefore, the generated EHV-1 ORF68 negative mutant could be a prospective candidate for the development of a vaccine marker.
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Affiliation(s)
- Emad Beshir Ata
- Department of Parasitology and Animal Diseases, Veterinary Research Division, National Research Centre (NRC), Egypt; Laboratory of Veterinary Microbiology, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan.
| | - Ahmed Zaghawa
- Department of Internal Medicine and Infectious Diseases, Faculty of Veterinary Medicine, Sadat City University, Egypt
| | - Alaa A Ghazy
- Department of Parasitology and Animal Diseases, Veterinary Research Division, National Research Centre (NRC), Egypt
| | - Ahmed Elsify
- Department of Internal Medicine and Infectious Diseases, Faculty of Veterinary Medicine, Sadat City University, Egypt
| | - Khaled Abdelrahman
- Department of Parasitology and Animal Diseases, Veterinary Research Division, National Research Centre (NRC), Egypt
| | - Samy Kasem
- Department of Virology, Faculty of Veterinary Medicine, Kafrelsheikh University, 33516, El-Geish street, Kafrelsheikh, Egypt; Laboratory of Veterinary Microbiology, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Mohamed Nayel
- Department of Internal Medicine and Infectious Diseases, Faculty of Veterinary Medicine, Sadat City University, Egypt; Laboratory of Veterinary Microbiology, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
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16
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Okada A, Suganuma S, Badr Y, Omatsu T, Mizutani T, Ohya K, Fukushi H. Decreased expression of the immediate early protein, ICP4, by deletion of the tegument protein VP22 of equine herpesvirus type 1. J Vet Med Sci 2017; 80:311-315. [PMID: 29279464 PMCID: PMC5836769 DOI: 10.1292/jvms.17-0380] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
VP22 is a major tegument protein of equine herpesvirus type 1 (EHV-1). In the present
study, we examined functions of VP22 in EHV-1 replication by viral protein expression
analyses in cells infected with the VP22-deficient virus. The expressions of several viral
proteins in the cells infected with the VP22-deficient virus were lower than those in the
cells infected with the parent virus. One of the weakly expressed proteins was identified
as ICP4, which is a major regulatory protein encoded by an immediate early gene of EHV-1.
A real-time PCR analysis showed that the mRNA expression of ICP4 was the same in cells
infected with the parent and VP22-deficient viruses. Hence, VP22 appears to promote
synthesis of ICP4 post-transcriptionally.
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Affiliation(s)
- Ayaka Okada
- Department of Applied Veterinary Sciences, United Graduated School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Shota Suganuma
- Laboratory of Veterinary Microbiology, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Yassien Badr
- Department of Applied Veterinary Sciences, United Graduated School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan.,Department of Animal Medicine, Faculty of Veterinary Medicine, Damanhour University, El-Beheira, Egypt
| | - Tsutomu Omatsu
- Research and Education Center for Prevention of Global Infectious Diseases of Animals, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan
| | - Tetsuya Mizutani
- Research and Education Center for Prevention of Global Infectious Diseases of Animals, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan
| | - Kenji Ohya
- Department of Applied Veterinary Sciences, United Graduated School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan.,Laboratory of Veterinary Microbiology, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Hideto Fukushi
- Department of Applied Veterinary Sciences, United Graduated School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan.,Laboratory of Veterinary Microbiology, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
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17
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Badr Y, Okada A, Abo-Sakaya R, Beshir E, Ohya K, Fukushi H. Equine herpesvirus type 1 ORF51 encoding UL11 as an essential gene for replication in cultured cells. Arch Virol 2017; 163:599-607. [DOI: 10.1007/s00705-017-3650-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 11/03/2017] [Indexed: 10/18/2022]
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18
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Gao X, Jia R, Wang M, Yang Q, Chen S, Liu M, Yin Z, Cheng A. Duck enteritis virus (DEV) UL54 protein, a novel partner, interacts with DEV UL24 protein. Virol J 2017; 14:166. [PMID: 28851454 PMCID: PMC5575879 DOI: 10.1186/s12985-017-0830-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 08/14/2017] [Indexed: 11/10/2022] Open
Abstract
Background UL24 is a multifunctional protein that is conserved among alphaherpesviruses and is believed to play an important role in viral infection and replication. Results In this paper, to investigate putative UL24-binding proteins and to explore the functional mechanisms of DEV UL24, yeast two-hybrid (Y2H) was carried out, and further verified the interaction between UL24 and partners by co-immunoprecipitation and fluorescence microscopy experiments. Interaction partners of UL24 protein were screened by yeast two-hybrid (Y2H) with the cDNA library of DEV-CHv strain post-infection DEF cells. A novel partner, DEV UL54 protein, was discovered by Y2H screening and bioinformatic. Co-immunoprecipitation experiments suggested that DEV UL24 interacted with UL54 proteins. And distribution of a part of UL54 protein was changed from nucleus to cytoplasm in DF-1 cells of co-subcellular localization experiments which also showed that DEV UL24 interacted with UL54 proteins. Conclusions The interaction between the DEV UL24 and UL54 proteins was discovered for the first time. Thus, DEV UL54 protein as a novel partner interacted with DEV UL24 protein. Electronic supplementary material The online version of this article (doi:10.1186/s12985-017-0830-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Xinghong Gao
- Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China.,Key Laboratory of Infectious Disease & Bio-safety, Provincial Department of Education, Zunyi Medical University, Zunyi, Guizhou, 563000, People's Republic of China.,Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China
| | - Renyong Jia
- Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China. .,Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China. .,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, 611130, China.
| | - Mingshu Wang
- Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China.,Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, 611130, China
| | - Qiao Yang
- Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China.,Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, 611130, China
| | - Shun Chen
- Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China.,Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, 611130, China
| | - Mafeng Liu
- Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China.,Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, 611130, China
| | - Zhongqiong Yin
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, 611130, China
| | - Anchun Cheng
- Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China. .,Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, 611130, China. .,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, 611130, China.
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19
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Equine herpesvirus type 1 induces both neurological and respiratory disease in Syrian hamsters. Vet Microbiol 2017; 203:117-124. [DOI: 10.1016/j.vetmic.2017.03.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 03/02/2017] [Accepted: 03/03/2017] [Indexed: 11/19/2022]
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20
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Herpes Simplex Virus 1 UL24 Abrogates the DNA Sensing Signal Pathway by Inhibiting NF-κB Activation. J Virol 2017; 91:JVI.00025-17. [PMID: 28100608 DOI: 10.1128/jvi.00025-17] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Accepted: 01/09/2017] [Indexed: 12/22/2022] Open
Abstract
Cyclic GMP-AMP synthase (cGAS) is a newly identified DNA sensor that recognizes foreign DNA, including the genome of herpes simplex virus 1 (HSV-1). Upon binding of viral DNA, cGAS produces cyclic GMP-AMP, which interacts with and activates stimulator of interferon genes (STING) to trigger the transcription of antiviral genes such as type I interferons (IFNs), and the production of inflammatory cytokines. HSV-1 UL24 is widely conserved among members of the herpesviruses family and is essential for efficient viral replication. In this study, we found that ectopically expressed UL24 could inhibit cGAS-STING-mediated promoter activation of IFN-β and interleukin-6 (IL-6), and UL24 also inhibited interferon-stimulatory DNA-mediated IFN-β and IL-6 production during HSV-1 infection. Furthermore, UL24 selectively blocked nuclear factor κB (NF-κB) but not IFN-regulatory factor 3 promoter activation. Coimmunoprecipitation analysis demonstrated that UL24 bound to the endogenous NF-κB subunits p65 and p50 in HSV-1-infected cells, and UL24 was also found to bind the Rel homology domains (RHDs) of these subunits. Furthermore, UL24 reduced the tumor necrosis factor alpha (TNF-α)-mediated nuclear translocation of p65 and p50. Finally, mutational analysis revealed that the region spanning amino acids (aa) 74 to 134 of UL24 [UL24(74-134)] is responsible for inhibiting cGAS-STING-mediated NF-κB promoter activity. For the first time, UL24 was shown to play an important role in immune evasion during HSV-1 infection.IMPORTANCE NF-κB is a critical component of the innate immune response and is strongly induced downstream of most pattern recognition receptors (PRRs), leading to the production of IFN-β as well as a number of inflammatory chemokines and interleukins. To establish persistent infection, viruses have evolved various mechanisms to counteract the host NF-κB pathway. In the present study, for the first time, HSV-1 UL24 was demonstrated to inhibit the activation of NF-κB in the DNA sensing signal pathway via binding to the RHDs of the NF-κB subunits p65 and p50 and abolishing their nuclear translocation.
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21
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Kobayashi Y, Tanahashi R, Yamaguchi Y, Hatae N, Kobayashi M, Ueno Y, Yoshimatsu M. Ni-Pd Catalyzed Cyclization of Sulfanyl 1,6-Diynes: Synthesis of 1'-Homonucleoside Analogues. J Org Chem 2017; 82:2436-2449. [PMID: 28151664 DOI: 10.1021/acs.joc.6b02841] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The Ni-Pd catalyzed addition-cyclization of sulfanyl 1,6-diynes 2-9 with nucleobases is described. The reactions of N-tethered 1,6-diynes with N3-benzoylthymine, N4,N4-bis(Boc)cytosine, N3-benzoyluracil and N6,N6-bis(Boc)adenine exclusively afforded the pyrrolylmethyl and furylmethyl nucleotides in good yields. Deprotection of nucleobases was completed by treatment with acids or bases. Furthermore, the reactions of pyrroles and furans with nucleophiles such as alkoxides and amines underwent detosylation and conversion to the alkoxymethyl- and arylaminomethyl-pyrroles and furans in good yields.
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Affiliation(s)
- Yuka Kobayashi
- Department of Chemistry, Faculty of Education, Gifu University , Yanagido 1-1, Gifu 501-1193, Japan
| | - Rena Tanahashi
- Department of Chemistry, Faculty of Education, Gifu University , Yanagido 1-1, Gifu 501-1193, Japan
| | - Yui Yamaguchi
- Laboratory of Veterinary Microbiology, Faculty of Applied Biological Sciences, Gifu University , Yanagido 1-1, Gifu 501-1193, Japan
| | - Noriyuki Hatae
- School of Pharmaceutical Sciences, Health Science University of Hokkaido , Ishikari-Tobetsu, Hokkaido 061-0293, Japan
| | - Masanori Kobayashi
- Organization for Research and Community Development, Department of Research Promotion, Gifu University , Yanagido 1-1, Gifu 501-1193, Japan
| | - Yoshihito Ueno
- Department of Smart Material Science, The United Graduate School of Agricultural Science, Gifu University , Yanagido 1-1, Gifu 501-1193, Japan
| | - Mitsuhiro Yoshimatsu
- Department of Chemistry, Faculty of Education, Gifu University , Yanagido 1-1, Gifu 501-1193, Japan.,Laboratory of Veterinary Microbiology, Faculty of Applied Biological Sciences, Gifu University , Yanagido 1-1, Gifu 501-1193, Japan
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22
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Ma Y, Liu D, Gao J, Wang X. Similar regulation of two distinct UL24 promoters by regulatory proteins of equine herpesvirus type 1 (EHV-1). FEBS Lett 2015; 589:1467-75. [PMID: 25937123 DOI: 10.1016/j.febslet.2015.04.039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2014] [Revised: 04/16/2015] [Accepted: 04/21/2015] [Indexed: 11/17/2022]
Abstract
To characterise the pattern of the transcriptional regulation of equine herpesvirus type 1 (EHV-1) UL24 by regulatory proteins, we identified two distinct promoter regions and two transcription initiation (Tci) sites located upstream of the UL24 open reading frame (ORF). The ORF proximal promoter exhibited higher cis-activity than that of the distal one. Contrary to the former, the latter performed its function dependent on an initiator (INR) due to its lack of a TATA box. Our results showed that the EHV-1 regulatory proteins EICP0, EICP22 and ETIF trans-activated the two promoters, whereas IEP and IR2P displayed negative regulation. In summary, the regulatory proteins exhibited similar regulatory patterns for the two distinct promoters of EHV-1 UL24.
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Affiliation(s)
- Yue Ma
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Diqiu Liu
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Jun Gao
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, China
| | - Xiaojun Wang
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China; College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, China.
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23
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Mori E, Lara MDCCSH, Cunha EMS, Villalobos EMC, Mori CMC, Soares RM, Brandão PE, Fernandes WR, Richtzenhain LJ. Molecular characterization of Brazilian equid herpesvirus type 1 strains based on neuropathogenicity markers. Braz J Microbiol 2015; 46:565-70. [PMID: 26273275 PMCID: PMC4507552 DOI: 10.1590/s1517-838246220140096] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2014] [Accepted: 10/30/2014] [Indexed: 11/22/2022] Open
Abstract
Partial nucleotide sequences of ORF72 (glycoprotein D, gD), ORF64 (infected cell protein 4, ICP4) and ORF30 (DNA polymerase) genes were compared with corresponding sequences of EHV-1 reference strains to characterize the molecular variability of Brazilian strains. Virus isolation assays were applied to 74 samples including visceral tissue, total blood, cerebrospinal fluid (CSF) and nasal swabs of specimens from a total of 64 animals. Only one CSF sample (Iso07/05 strain) was positive by virus isolation in cell culture. EHV-1 Iso07/05 neurologic strain and two abortion visceral tissues samples (Iso11/06 and Iso33/06) were PCR-positive for ORF33 (glycoprotein B, gB) gene of EHV-1. A sequence analysis of the ORF72, ORF64 and ORF30 genes from three EHV-1 archival strains (A3/97, A4/72, A9/92) and three clinical samples (Iso07/05, Iso11/06 and Iso33/06) suggested that among Brazilian EHV-1 strains, the amplified region of the gD gene sequence is highly conserved. Additionally, the analysis of ICP4 gene showed high nucleotide and amino acid identities when compared with genotype P strains, suggesting that the EHV-1 Brazilian strains belonged to the same group. All the EHV-1 Brazilian strains were classified as non-neuropathogenic variants (N752) based on the ORF30 analysis. These findings indicate a high conservation of the gD-, ICP4- and ORF30-encoding sequences. Different pathotypes of the EHV-1 strain might share identical genes with no specific markers, and tissue tropism is not completely dependent on the gD envelope, immediate-early ICP4 and DNA polymerase proteins.
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Affiliation(s)
- Enio Mori
- Instituto Pasteur, São Paulo, SP, Brasil, Instituto Pasteur, São Paulo, SP, Brazil. ; Universidade de São Paulo, Departamento de Patologia, Faculdade de Medicina Veterinária e Ciência Animal, Universidade de São Paulo, São Paulo, SP, Brasil, Departamento de Patologia, Faculdade de Medicina Veterinária e Ciência Animal, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Maria do Carmo C S H Lara
- Instituto Biológico, Instituto Biológico, São Paulo, SP, Brasil, Instituto Biológico, São Paulo, SP, Brazil
| | - Elenice M S Cunha
- Instituto Biológico, Instituto Biológico, São Paulo, SP, Brasil, Instituto Biológico, São Paulo, SP, Brazil
| | - Eliana M C Villalobos
- Instituto Biológico, Instituto Biológico, São Paulo, SP, Brasil, Instituto Biológico, São Paulo, SP, Brazil
| | - Claudia M C Mori
- Universidade de São Paulo, Departamento de Patologia, Faculdade de Medicina Veterinária e Ciência Animal, Universidade de São Paulo, São Paulo, SP, Brasil, Departamento de Patologia, Faculdade de Medicina Veterinária e Ciência Animal, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Rodrigo M Soares
- Universidade de São Paulo, Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP, Brasil, Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Paulo E Brandão
- Universidade de São Paulo, Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP, Brasil, Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Wilson R Fernandes
- Universidade de São Paulo, Departamento de Clínica Médica, Faculdade de Medicina Veterinária e Ciência Animal, Universidade de São Paulo, São Paulo, SP, Brasil, Departamento de Clínica Médica, Faculdade de Medicina Veterinária e Ciência Animal, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Leonardo J Richtzenhain
- Universidade de São Paulo, Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP, Brasil, Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP, Brazil
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24
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Rochette PA, Bourget A, Sanabria-Solano C, Lahmidi S, Lavallée GO, Pearson A. Mutation of UL24 impedes the dissemination of acute herpes simplex virus 1 infection from the cornea to neurons of trigeminal ganglia. J Gen Virol 2015; 96:2794-2805. [PMID: 25986633 DOI: 10.1099/vir.0.000189] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Herpes simplex virus 1 (human herpesvirus 1) initially infects epithelial cells of the mucosa and then goes on to infect sensory neurons leading ultimately to a latent infection in trigeminal ganglia (TG). UL24 is a core herpesvirus gene that has been identified as a determinant of pathogenesis in several Alphaherpesvirinae, although the underlying mechanisms are unknown. In a mouse model of ocular infection, a UL24-deficient virus exhibited a reduction in viral titres in tear films of 1 log10, whilst titres in TG are often below the level of detection. Moreover, the efficiency of reactivation from latency was also severely reduced. Herein, we investigated how UL24 contributed to acute infection of TG. Our results comparing the impact of UL24 on viral titres in eye tissue versus in tear films did not reveal a general defect in virus release from the cornea. We also found that the impairment of replication seen in mouse primary embryonic neurons with a UL24-deficient virus was not more severe than that observed in an epithelial cell line. Rather, in situ histological analyses revealed that infection with a UL24-deficient virus led to a significant reduction in the number of acutely infected neurons at 3 days post-infection (p.i.). Moreover, there was a significant reduction in the number of neurons positive for viral DNA at 2 days p.i. for the UL24-deficient virus as compared with that observed for WT or a rescue virus. Our results supported a model whereby UL24 functions in the dissemination of acute infection from the cornea to neurons in TG.
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Affiliation(s)
- Pierre-Alexandre Rochette
- Université INRS, INRS-Institut Armand-Frappier, 531 boulevard des Prairies, Laval, Québec H7V 1B7, Canada
| | - Amélie Bourget
- Université INRS, INRS-Institut Armand-Frappier, 531 boulevard des Prairies, Laval, Québec H7V 1B7, Canada
| | - Carolina Sanabria-Solano
- Université INRS, INRS-Institut Armand-Frappier, 531 boulevard des Prairies, Laval, Québec H7V 1B7, Canada
| | - Soumia Lahmidi
- Université INRS, INRS-Institut Armand-Frappier, 531 boulevard des Prairies, Laval, Québec H7V 1B7, Canada
| | - Gabriel Ouellet Lavallée
- Université INRS, INRS-Institut Armand-Frappier, 531 boulevard des Prairies, Laval, Québec H7V 1B7, Canada
| | - Angela Pearson
- Université INRS, INRS-Institut Armand-Frappier, 531 boulevard des Prairies, Laval, Québec H7V 1B7, Canada
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25
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Okada A, Izume S, Ohya K, Fukushi H. Equine herpesvirus type 1 tegument protein VP22 is not essential for pathogenicity in a hamster model, but is required for efficient viral growth in cultured cells. J Vet Med Sci 2015; 77:1293-7. [PMID: 25948053 PMCID: PMC4638299 DOI: 10.1292/jvms.14-0648] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
VP22 is a major tegument protein of Equine herpesvirus type 1 (EHV-1) that is a conserved
protein among alphaherpesviruses. However, the roles of VP22 differ among each virus, and
the roles of EHV-1 VP22 are still unclear. Here, we constructed an EHV-1 VP22 deletion
mutant and a revertant virus to clarify the role of VP22. We found that EHV-1 VP22 was
required for efficient viral growth in cultured cells, but not for virulence in a hamster
model.
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Affiliation(s)
- Ayaka Okada
- Department of Applied Veterinary Sciences, United Graduate School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
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26
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Okada A, Kodaira A, Hanyu S, Izume S, Ohya K, Fukushi H. Intracellular localization of Equine herpesvirus type 1 tegument protein VP22. Virus Res 2014; 192:103-13. [PMID: 25192624 DOI: 10.1016/j.virusres.2014.08.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 08/14/2014] [Accepted: 08/14/2014] [Indexed: 11/22/2022]
Abstract
Intracellular localization of Equine herpesvirus type 1 (EHV-1) tegument protein VP22 was examined by using a plasmid that expressed VP22 fused with an enhanced green fluorescent protein (EGFP). Also a recombinant EHV-1 expressing VP22 fused with a red fluorescent protein (mCherry) was constructed to observe the localization of VP22 in infected cells. When EGFP-fused VP22 was overexpressed in the cells, VP22 localized in the cytoplasm and nucleus. Live cell imaging suggested that the fluorescently tagged VP22 also localized in the cytoplasm and nucleus. These results show that VP22 localizes in the cytoplasm and nucleus independently of other viral proteins. Experiments with truncation mutants of pEGFP-VP22 suggested that 154-188 aa might be the nuclear localization signal of EHV-1 VP22.
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Affiliation(s)
- Ayaka Okada
- Department of Applied Veterinary Sciences, United Graduated School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Akari Kodaira
- Department of Applied Veterinary Sciences, United Graduated School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Sachiko Hanyu
- Department of Applied Veterinary Sciences, United Graduated School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Satoko Izume
- Department of Applied Veterinary Sciences, United Graduated School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Kenji Ohya
- Department of Applied Veterinary Sciences, United Graduated School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan; Laboratory of Veterinary Microbiology, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Hideto Fukushi
- Department of Applied Veterinary Sciences, United Graduated School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan; Laboratory of Veterinary Microbiology, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan.
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27
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Vaccination with a HSV-2 UL24 mutant induces a protective immune response in murine and guinea pig vaginal infection models. Vaccine 2014; 32:1398-406. [PMID: 24462481 DOI: 10.1016/j.vaccine.2013.10.079] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Revised: 09/25/2013] [Accepted: 10/24/2013] [Indexed: 11/21/2022]
Abstract
The rational design and development of genetically attenuated HSV-2 mutant viruses represent an attractive approach for developing both prophylactic and therapeutic vaccines for genital herpes. Previously, HSV-2 UL24 was shown to be a virulence determinant in both murine and guinea pig vaginal infection models. An UL24-βgluc insertion mutant produced syncytial plaques and replicated to nearly wild type levels in tissue culture, but induced little or no pathological effects in recipient mice or guinea pigs following vaginal infection. Here we report that immunization of mice or guinea pigs with high or low doses of UL24-βgluc elicited a highly protective immune response. UL24-βgluc immunization via the vaginal or intramuscular routes was demonstrated to protect mice from a lethal vaginal challenge with wild type HSV-2. Moreover, antigen re-stimulated splenic lymphocytes harvested from immunized mice exhibited both HSV-2 specific CTL activity and IFN-γ expression. Humoral anti-HSV-2 responses in serum were Th1-polarized (IgG2a>IgG1) and contained high-titer anti-HSV-2 neutralizing activity. Guinea pigs vaccinated subcutaneously with UL24-βgluc or the more virulent parental strain (186) were challenged with a heterologous HSV-2 strain (MS). Acute disease scores were nearly indistinguishable in guinea pigs immunized with either virus. Recurrent disease scores were reduced in UL24-βgluc immunized animals but not to the same extent as those immunized with strain 186. In addition, challenge virus was not detected in 75% of guinea pigs subcutaneously immunized with UL24-βgluc. In conclusion, disruption of the UL24 gene is a prime target for the development of a genetically attenuated live HSV-2 vaccine.
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28
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Comparing the genetic diversity of ORF30 of Australian isolates of 3 equid alphaherpesviruses. Vet Microbiol 2013; 169:50-7. [PMID: 24418044 DOI: 10.1016/j.vetmic.2013.12.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Revised: 12/13/2013] [Accepted: 12/16/2013] [Indexed: 11/22/2022]
Abstract
A single nucleotide polymorphism (SNP) has been previously associated with EHV-1 neurological disease in several countries around the world. This disease is very uncommon in Australia and little information is available about the presence of this SNP in Australian EHV-1 isolates. The ORF30 sequence of 66 Australian EHV-1 isolates was determined and the genotype was compared to the disease manifestation of the case from which the virus was isolated. Of the 66 isolates, 61 were from cases of abortion and 5 were cases associated with equine herpesvirus myeloencephalopathy (EHM). There was no association between pathotype and genotype in these isolates. In total, 64 of the 66 isolates encoded N752, including 4 isolates from EHM cases. The ORF30 sequence was also determined for 14 EHV-4 isolates, including 2 isolates from confirmed EHV-4 abortion cases. All 14 EHV-4 isolates had aspartic acid at the position equivalent to EHV-1 AA752. Aspartic acid was also confirmed in this position for the single isolate of AHV-3 sequenced in this study. The nucleotide sequence of ORF68 was also determined and showed considerable genetic heterogeneity in the EHV-1 isolates, however, this ORF was highly conserved among the 14 EHV-4 isolates sequenced, with only one SNP identified among 7 isolates. These results confirm that the EHV1 ORF30 N752 is unique and that the D752 sequence is most likely to be the true parent strain of this virus. We suggest that the abortigenic form of EHV-1 should be considered to be the more recently emerged mutant.
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29
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Ma G, Azab W, Osterrieder N. Equine herpesviruses type 1 (EHV-1) and 4 (EHV-4)—Masters of co-evolution and a constant threat to equids and beyond. Vet Microbiol 2013; 167:123-34. [DOI: 10.1016/j.vetmic.2013.06.018] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2013] [Revised: 05/08/2013] [Accepted: 06/28/2013] [Indexed: 12/28/2022]
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30
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Human cytomegalovirus UL76 elicits novel aggresome formation via interaction with S5a of the ubiquitin proteasome system. J Virol 2013; 87:11562-78. [PMID: 23966401 DOI: 10.1128/jvi.01568-13] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
HCMV UL76 is a member of a conserved Herpesviridae protein family (Herpes_UL24) that is involved in viral production, latency, and reactivation. UL76 presents as globular aggresomes in the nuclei of transiently transfected cells. Bioinformatic analyses predict that UL76 has a propensity for aggregation and targets cellular proteins implicated in protein folding and ubiquitin-proteasome systems (UPS). Furthermore, fluorescence recovery after photobleaching experiments suggests that UL76 reduces protein mobility in the aggresome, which indicates that UL76 elicits the aggregation of misfolded proteins. Moreover, in the absence of other viral proteins, UL76 interacts with S5a, which is a major receptor of polyubiquitinated proteins for UPS proteolysis via its conserved region and the von Willebrand factor type A (VWA) domain of S5a. We demonstrate that UL76 sequesters polyubiquitinated proteins and S5a to nuclear aggresomes in biological proximity. After knockdown of endogenous S5a by RNA interference techniques, the UL76 level was only minimally affected in transiently expressing cells. However, a significant reduction in the number of cells containing UL76 nuclear aggresomes was observed, which suggests that S5a may play a key role in aggresome formation. Moreover, we show that UL76 interacts with S5a in the late phase of viral infection and that knockdown of S5a hinders the development of both the replication compartment and the aggresome. In this study, we demonstrate that UL76 induces a novel nuclear aggresome, likely by subverting S5a of the UPS. Given that UL76 belongs to a conserved family, this underlying mechanism may be shared by all members of the Herpesviridae.
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Mori C, Mori E, Favaro L, Santos C, Lara M, Villalobos E, Cunha E, Brandao P, Richtzenhain L, Maiorka P. Equid Herpesvirus Type-1 Exhibits Neurotropism and Neurovirulence in a Mouse Model. J Comp Pathol 2012; 146:202-10. [DOI: 10.1016/j.jcpa.2011.04.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Revised: 04/01/2011] [Accepted: 04/12/2011] [Indexed: 11/30/2022]
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Yu MHH, Kasem S, Yoshizaki N, Pagamjav O, Yamaguchi T, Ohya K, Fukushi H. Functional characterization of EUL47 in productive replication, morphogenesis and infectivity of equine herpesvirus 1. Virus Res 2012; 163:310-9. [DOI: 10.1016/j.virusres.2011.10.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Revised: 10/15/2011] [Accepted: 10/20/2011] [Indexed: 10/15/2022]
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Carvalho RF, Spilki FR, Cunha EM, Stocco RC, Arns CW. Molecular data of UL24 homolog gene (ORF37) from Brazilian isolates of equine herpesvirus type 1. Res Vet Sci 2011; 93:494-7. [PMID: 21684566 DOI: 10.1016/j.rvsc.2011.05.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2009] [Revised: 05/06/2011] [Accepted: 05/23/2011] [Indexed: 10/18/2022]
Abstract
Equine herpesvirus type 1 (EHV-1) is associated with abortions, respiratory distress, and neurological disturbances in horses. The ORF37 of EHV-1 encodes a protein homolog to UL24 gene product of human herpesvirus that has been associated with neurovirulence. In the present work, ORF37 PCR fragments derived from two Brazilian EHV-1 isolates, a German isolate and an American reference strain were sequenced and characterized by molecular phylogenetic analysis. This genomic region is highly conserved an allowed to infer genetic distances between EHV-1 strains and other animal herpesvirus.
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Affiliation(s)
- R F Carvalho
- Laboratório de Genética, Instituto Butantan, São Paulo, SP, CEP 05503-900, Brazil.
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Azab W, Kato K, Abdel-Gawad A, Tohya Y, Akashi H. Equine herpesvirus 4: recent advances using BAC technology. Vet Microbiol 2011; 150:1-14. [PMID: 21292410 DOI: 10.1016/j.vetmic.2011.01.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Revised: 12/17/2010] [Accepted: 01/03/2011] [Indexed: 10/18/2022]
Abstract
The equine herpesviruses are major infectious pathogens that threaten equine health. Equine herpesvirus 4 (EHV-4) is an important equine pathogen that causes respiratory tract disease, known as rhinopneumonitis, among horses worldwide. EHV-4 genome manipulation with subsequent understanding of the viral gene functions has always been difficult due to the limited number of susceptible cell lines and the absence of small-animal models of the infection. Efficient generation of mutants of EHV-4 would significantly contribute to the rapid and accurate characterization of the viral genes. This problem has been solved recently by the cloning of the genome of EHV-4 as a stable and infectious bacterial artificial chromosome (BAC) without any deletions of the viral genes. Very low copy BAC vectors are the mainstay of present genomic research because of the high stability of inserted clones and the possibility of mutating any gene target in a relatively short time. Manipulation of EHV-4 genome is now feasible using the power of BAC technology, and should aid greatly in assessing the role of viral genes in the virus-host interaction.
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Affiliation(s)
- Walid Azab
- Department of Veterinary Microbiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
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