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Li H, Cao X, Chen R, Guang M, Xu M, Wu X, Yang R, Lei L, Zhang F. Rapid detection of grass carp reovirus type 1 using RPA-based test strips combined with CRISPR Cas13a system. Front Microbiol 2023; 14:1296038. [PMID: 38029146 PMCID: PMC10654748 DOI: 10.3389/fmicb.2023.1296038] [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: 09/18/2023] [Accepted: 10/19/2023] [Indexed: 12/01/2023] Open
Abstract
Introduction Due to the existence of grass carp reovirus (GCRV), grass carp hemorrhagic disease occurs frequently, and its high pathogenicity and infectivity are great challenges to the aquaculture industry. As a highly pathogenic pathogen, the outbreak of hemorrhagic disease often causes tremendous economic losses. Therefore, it is important to rapidly and accurately detect GCRV on site to control timely. Methods In this study, recombinant enzyme amplification (RPA) combined with clustered regularly interspaced short palindromic repeats (CRISPR)/Cas13a system was employed to establish a method to detect the vp7 gene of grass carp reovirus type 1. This method can be adopted for judging the results by collecting fluorescence signal, ultraviolet excitation visual fluorescence and test strip. Results Combined with the RPA amplification experiment, the detection limit of the RPA-CRISPR method can reach 7.2 × 101 copies/μL of vp7 gene per reaction, and the detection process can be completed within 1 h. In addition, this method had no cross-reaction with the other 11 common aquatic pathogens. Then, the performance of the RPA-CRISPR/Cas13a detection method was evaluated by comparing it with the real-time fluorescence quantitative PCR detection method of clinical samples. The results of RPA-CRISPR/Cas13a detection were shown to be in consistence with the results obtained from the real-time fluorescence quantitative PCR detection. The coincidence rate of this method with 26 GCRV clinical samples was 92.31%. Discussion In summary, this method has high sensitivity, specificity and on-site practicability for detecting GCRV type 1, and has great application potential in on-site GCRV monitoring.
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Affiliation(s)
- Huaming Li
- College of Animal Science, Yangtze University, Jingzhou, China
| | - Xinyue Cao
- College of Animal Science, Yangtze University, Jingzhou, China
| | - Ruige Chen
- College of Animal Science, Yangtze University, Jingzhou, China
| | - Min Guang
- College of Animal Science, Yangtze University, Jingzhou, China
| | - Mengran Xu
- College of Animal Science, Yangtze University, Jingzhou, China
| | - Xiaomin Wu
- College of Animal Science, Yangtze University, Jingzhou, China
| | - Rongrong Yang
- College of Animal Science, Yangtze University, Jingzhou, China
| | - Liancheng Lei
- College of Veterinary Medicine, Jilin University, Changchun, China
| | - Fuxian Zhang
- College of Animal Science, Yangtze University, Jingzhou, China
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2
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Dai Y, Li Y, Hu X, Jiang N, Liu W, Meng Y, Zhou Y, Xu C, Xue M, Fan Y. Nonstructural protein NS17 of grass carp reovirus Honghu strain promotes virus infection by mediating cell-cell fusion and apoptosis. Virus Res 2023; 334:199150. [PMID: 37302658 PMCID: PMC10410512 DOI: 10.1016/j.virusres.2023.199150] [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: 04/21/2023] [Revised: 06/07/2023] [Accepted: 06/08/2023] [Indexed: 06/13/2023]
Abstract
Fusion-associated small transmembrane (FAST) proteins can promote cell fusion, alter membrane permeability and trigger apoptosis to promote virus proliferation in orthoreoviruses. However, it is unknown whether FAST proteins perform these functions in aquareoviruses (AqRVs). Non-structural protein 17 (NS17) carried by grass carp reovirus Honghu strain (GCRV-HH196) belongs to the FAST protein family, and we preliminarily explored its relevance to virus infection. NS17 has similar domains to FAST protein NS16 of GCRV-873, comprising a transmembrane domain, a polybasic cluster, a hydrophobic patch and a polyproline motif. It was observed in the cytoplasm and the cell membrane. Overexpression of NS17 enhanced the efficiency of cell-cell fusion induced by GCRV-HH196 and promoted virus replication. Overexpression of NS17 also led to DNA fragmentation and reactive oxygen species (ROS) accumulation, and it triggered apoptosis. The findings illuminate the functions of NS17 in GCRV infection, and provide a reference for the development of novel antiviral strategies.
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Affiliation(s)
- Yanlin Dai
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai 201306, China
| | - Yiqun Li
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China.
| | - Xi Hu
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai 201306, China
| | - Nan Jiang
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China
| | - Wenzhi Liu
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China
| | - Yan Meng
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China
| | - Yong Zhou
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China
| | - Chen Xu
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China
| | - Mingyang Xue
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China
| | - Yuding Fan
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai 201306, China.
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3
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Zhu W, Qiao M, Hu M, Huo X, Zhang Y, Su J. Type II Grass Carp Reovirus Rapidly Invades Grass Carp ( Ctenopharyngodon idella) via Nostril-Olfactory System-Brain Axis, Gill, and Skin on Head. Viruses 2023; 15:1614. [PMID: 37515300 PMCID: PMC10385732 DOI: 10.3390/v15071614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 07/17/2023] [Accepted: 07/18/2023] [Indexed: 07/30/2023] Open
Abstract
Type II grass carp reovirus (GCRV-II) with high pathogenicity and infectivity causes severe hemorrhagic disease, which leads to extensive death in the grass carp and black carp aquaculture. However, the early invasion portal remains unclear. In this study, we explored the invasion portal, time, and pathway of GCRV-II by immersion infection in grass carp. Through the detection of the infected grass carp external body surface tissues, most of them could be detected to carry GCRV-II within 45 min except for the skin covered by scales. Further shortening the duration of infection, we proved that GCRV-II rapidly invades through the nostril (especially), gill, and skin on head at only 5 min post-immersion, rather than merely by adhesion. Subsequently, visual localization investigations of GCRV-II were conducted on the nostril, olfactory system (olfactory bulb and olfactory tract), and brain via immunofluorescence microscopy and transmission electron microscopy. We found that few viruses were located in the nostril at 5 min post-immersion infection, while a significantly increased quantity of viruses were distributed in all of the examined tissues at 45 min. Furthermore, the semi-qRT-PCR and Western blotting results of different infection times confirmed that GCRV-II invades grass carp via the nostril-olfactory system-brain axis and then viral replication unfolds. These results revealed the infection mechanism of GCRV-II in terms of the invasion portal, time, and pathway in grass carp. This study aims to understand the invasion mode of GCRV-II in grass carp, thus providing theoretical support for the prevention and control strategies of hemorrhagic disease.
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Affiliation(s)
- Wentao Zhu
- College of Fisheries, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China
- Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao 266237, China
| | - Meihua Qiao
- College of Fisheries, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China
| | - Meidi Hu
- College of Fisheries, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China
| | - Xingchen Huo
- College of Fisheries, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China
| | - Yongan Zhang
- College of Fisheries, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China
| | - Jianguo Su
- College of Fisheries, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China
- Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao 266237, China
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Stevens A, Cui Y, Shivakoti S, Zhou ZH. Asymmetric reconstruction of the aquareovirus core at near-atomic resolution and mechanism of transcription initiation. Protein Cell 2023; 14:544-548. [PMID: 36856784 PMCID: PMC10305738 DOI: 10.1093/procel/pwad002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/30/2022] [Indexed: 02/05/2023] Open
Affiliation(s)
- Alexander Stevens
- Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles (UCLA), 609 Charles E Young Dr E, Los Angeles, CA 90095, USA
- California NanoSystems Institute, UCLA, 570 Westwood Plaza Building 114 | Mail Code: 722710, Los Angeles, CA 90095, USA
- Department of Chemistry and Biochemistry, UCLA, 607 Charles E. Young Drive East | Box 951569, Los Angeles, CA 90095-1569, USA
| | - Yanxiang Cui
- California NanoSystems Institute, UCLA, 570 Westwood Plaza Building 114 | Mail Code: 722710, Los Angeles, CA 90095, USA
| | - Sakar Shivakoti
- Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles (UCLA), 609 Charles E Young Dr E, Los Angeles, CA 90095, USA
| | - Z Hong Zhou
- Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles (UCLA), 609 Charles E Young Dr E, Los Angeles, CA 90095, USA
- California NanoSystems Institute, UCLA, 570 Westwood Plaza Building 114 | Mail Code: 722710, Los Angeles, CA 90095, USA
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Jiang R, Zhang J, Liao Z, Zhu W, Su H, Zhang Y, Su J. Temperature-regulated type II grass carp reovirus establishes latent infection in Ctenopharyngodon idella brain. Virol Sin 2023:S1995-820X(23)00044-5. [PMID: 37137379 DOI: 10.1016/j.virs.2023.04.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 04/26/2023] [Indexed: 05/05/2023] Open
Abstract
Grass carp reovirus (GCRV) causes extensive infection and death in grass carp and black carp fingerlings, with a highly seasonal prevalence. Previous studies suggested that GCRV can become latent after primary infection. In this study, we investigated type II GCRV (GCRV-II) latency in asymptomatic grass carp with GCRV infection or exposure history. We found that during latent infection, GCRV-II was detectable only in the brain of grass carp, unlike the multi-tissue distribution observed in natural infection. GCRV-II only caused damage to the brain during latent infection, while in natural infection, brain, heart, and eye tissues had relatively higher viral loads. We also discovered viral inclusion bodies in infected fish brains. Additionally, GCRV-II distribution in grass carp was notably affected by ambient temperature, with the virus targeting the brain only during low temperatures and multi-tissue distribution during high temperatures. This study provides insights into the mechanisms of GCRV-II latent infection and reactivation and contributes to the prevention and control of GCRV pandemics.
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Affiliation(s)
- Rui Jiang
- College of Fisheries, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China; Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao, 266237, China
| | - Jie Zhang
- College of Fisheries, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Zhiwei Liao
- College of Fisheries, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Wentao Zhu
- College of Fisheries, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Hang Su
- College of Fisheries, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Yongan Zhang
- College of Fisheries, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Jianguo Su
- College of Fisheries, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China; Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao, 266237, China.
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Li J, Wu H, Xu W, Wang Y, Wang H, Wang Y, Li Y, Shi C, Bergmann SM, Mo X, Wang Q, Yin J. Development of a rapid and sensitive reverse transcription real-time quantitative PCR assay for detection and quantification of grass carp reovirus II. J Virol Methods 2023; 312:114663. [PMID: 36455690 DOI: 10.1016/j.jviromet.2022.114663] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 11/20/2022] [Accepted: 11/27/2022] [Indexed: 11/29/2022]
Abstract
Hemorrhagic disease of grass carp, which is induced by grass carp reovirus II (GCRV-II), leads to mass mortality in grass carp culture and causes enormous economic loss. However, there is currently no quantitative analysis method for the detection of GCRV-II, which is greatly restricted the etiological and epidemiological study of the disease. In this study a reverse transcription TaqMan PCR (RT-qPCR) assay was developed for the quantitative detection of GCRV-II. The probe and primers targeted location is the segment 6 (S6) region of the GCRV-II genome which is highly conserved. Standard curves were drawn and criteria were confirmed after the determination of the optimum reaction conditions. The species-specific assay showed that the method is highly specific and has no cross reactions with other pathogens. The assay was sufficiently sensitive to detect as low as 10 copies of virus RNA. Moreover, the method has a very good repeatability for batches and inter-batches sample detection. Then the method was applied to detect the virus in tissue samples from clinically infected grass carp, compared with conventional RT-seminested PCR, the RT-qPCR represents a specific value for detection rate of positive samples. In summary, the RT-qPCR was applied and achieved high sensitivity and specificity for GCRV-II detection.
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Affiliation(s)
- Jiahao Li
- Key Laboratory of Fishery Drug Development of Ministry of Agriculture and Rural Affairs, Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, Guangdong, PR China
| | - Huiliang Wu
- College of Veterinary Medicine, South China Agricultural University, China
| | - Wei Xu
- National Pathogen Collection Center for Aquatic Animals, Shanghai Ocean University, Shanghai 201306, China
| | - Yajun Wang
- Key Laboratory of Fishery Drug Development of Ministry of Agriculture and Rural Affairs, Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, Guangdong, PR China
| | - Hao Wang
- National Pathogen Collection Center for Aquatic Animals, Shanghai Ocean University, Shanghai 201306, China
| | - Yingying Wang
- Key Laboratory of Fishery Drug Development of Ministry of Agriculture and Rural Affairs, Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, Guangdong, PR China
| | - Yingying Li
- Key Laboratory of Fishery Drug Development of Ministry of Agriculture and Rural Affairs, Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, Guangdong, PR China
| | - Cunbin Shi
- Key Laboratory of Fishery Drug Development of Ministry of Agriculture and Rural Affairs, Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, Guangdong, PR China
| | - Sven M Bergmann
- Institute of Infectology, Friedrich-Loeffler-Institut (FLI), Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Xubing Mo
- Key Laboratory of Fishery Drug Development of Ministry of Agriculture and Rural Affairs, Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, Guangdong, PR China
| | - Qing Wang
- Key Laboratory of Fishery Drug Development of Ministry of Agriculture and Rural Affairs, Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, Guangdong, PR China.
| | - Jiyuan Yin
- Key Laboratory of Fishery Drug Development of Ministry of Agriculture and Rural Affairs, Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, Guangdong, PR China.
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7
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Zhang J, Chang MX. TBK1 Isoform Inhibits Grass Carp Reovirus Infection by Targeting the Degradation of Viral Nonstructural Proteins NS80 and NS38. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2023; 210:191-203. [PMID: 36445692 DOI: 10.4049/jimmunol.2200471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 11/03/2022] [Indexed: 01/03/2023]
Abstract
TANK-binding kinase 1 (TBK1) undergoes alternative splicing, and the previously reported TBK1 isoforms are negative regulators of RIG-I-like receptor-mediated type I IFN production. Although a study has suggested that grass carp TBK1 has an opposite effect at high- and low-titer of grass carp reovirus (GCRV) infection, the functions of grass carp TBK1 isoforms in GCRV infection remain unclear. In this study, we show that a TBK1 isoform from grass carp (Ctenopharyngodon idellus) named as gcTBK1_tv3, which has a 1-aa difference with zebrafish TBK1_tv3, inhibits the replication and infection of GCRV both at high and low titers of infection in C. idellus kidney cells. gcTBK1_tv3 can colocalize and interact with the NS80 and NS38 proteins of GCRV. Furthermore, gcTBK1_tv3 specifically degrades the NS80 and NS38 proteins of GCRV through the ubiquitin-proteasome pathway. Mechanistically, gcTBK1_tv3 promotes the degradation of NS80 or NS38 for K48-linked ubiquitination by targeting the Lys503 residue of NS80 or Lys328 residue of NS38, respectively, which ultimately impairs the production of cytoplasmic viral inclusion bodies and limits GCRV replication and infection. Taken together, our findings provide insight into the function of TBK1 isoform in the antiviral immune response and demonstrate that TBK1 isoform can target the nonstructural proteins of GCRV for impairing the formation of viral inclusion bodies.
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Affiliation(s)
- Jie Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Ming Xian Chang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China.,College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China; and.,Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, China
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8
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Zhang F, Sun D, Fang Q. Molecular Characterization of Outer Capsid Proteins VP5 and VP7 of Grass Carp Reovirus. Viruses 2022; 14:v14051032. [PMID: 35632773 PMCID: PMC9148132 DOI: 10.3390/v14051032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 05/09/2022] [Accepted: 05/09/2022] [Indexed: 12/20/2022] Open
Abstract
Aquareovirus, which is a member of the Reoviridae family, was isolated from aquatic animals. A close molecular evolutionary relationship between aquareoviruses and mammalian orthoreoviruses was revealed. However, the functions of the aquareovirus genome-encoded proteins are poorly understood. We investigated the molecular characteristics of the outer capsid proteins, namely, VP5 and VP7, of grass carp reovirus (GCRV). The peptides VP5 and VP7 were determined using in-gel tryptic digestion and mass spectrometry. Recovered peptides represented 76% and 66% of the full-length VP5 and VP7 sequences, respectively. Significantly, two-lysine acetylation, as well as two-serine and two-threonine phosphorylation modifications, were first revealed in VP5. We found that the initial amino acid in VP5 was Pro43, suggesting that a lower amount of VP5 remained uncleaved in virions at the autocleavage site (Asn42-Pro43). Further biochemical evidence showed that the cleaved VP5N/VP5C conformation was the major constituent of the particles. Moreover, early cleavage fragments of VP7 and enhanced infectivity were detected after limited tryptic digestion of GCRV, indicating that stepwise VP7 cleavage is essential for VP5 conformational rearrangement. Our results provide insights into the roles of posttranslational modifications in VP5 and its association with VP7 in the viral life cycle.
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Affiliation(s)
- Fuxian Zhang
- College of Animal Science, Yangtze University, Jingzhou 430023, China; (F.Z.); (D.S.)
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
| | - Diangang Sun
- College of Animal Science, Yangtze University, Jingzhou 430023, China; (F.Z.); (D.S.)
| | - Qin Fang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
- Correspondence: ; Tel.: +86-27-8719-8551
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9
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Wu M, Li H, Chen X, Jiang Y, Jiang W. Studies on the clinical symptoms, virus distribution, and mRNA expression of several antiviral immunity-related genes in grass carp after infection with genotype II grass carp reovirus. Arch Virol 2020; 165:1599-1609. [PMID: 32399788 DOI: 10.1007/s00705-020-04654-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 04/09/2020] [Indexed: 01/05/2023]
Abstract
The viral hemorrhage disease caused by grass carp reovirus (GCRV) is a serious contagious disease of grass carp that mainly infects fingerlings and yearlings. Epidemiological studies have shown that GCRV genotype II is currently the prominent genotype. However, little is known about the histopathological characteristics, virus distribution, and expression of immunity-related genes in grass carp infected by GCRV genotype II. In this study, we found that grass carp infected by GCRV genotype II lost appetite, swam alone, and rolled, and their fins, eyes, operculum, oral cavity, abdomen, intestine, and muscles showed pronounced punctate hemorrhage. Congestion, swelling, deformation, thinning of membranes, dilatation and darkened color of nucleoli, cathepsis, erythrocyte infiltration, and vacuole formation were observed in some infected tissues. A qRT-PCR test showed that the 11 genome segments of GCRV had similar expression patterns in different tissues. The S8 segment, with unknown function and no homologous sequences, had the highest expression level, while the most conserved segment, L2, had the lowest expression level. GCRV particles were distributed in different tissues, especially in the intestine. In the infected intestine, the expression of various receptors and adaptor molecules was modulated at different levels. Pro-inflammatory cytokine interleukin-1β (IL-1β) expression was 2160.9 times higher than that in the control group. The upregulation of immunity-related genes activated the antiviral immunity pathways. Therefore, the intestine might play a dual role in mediating GCRV infection and the antiviral immune response. This study provides detailed information about the pathogenicity of GCRV and expression of immunity-related genes, laying the foundation for further research on virus control and treatment.
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Affiliation(s)
- Minglin Wu
- Fisheries Research Institute, Anhui Academy of Agricultural Sciences, No. 40 South Nongke Road, Luyang District, Hefei, 230031, Anhui, China.
- Anhui Province Key Laboratory of Aquaculture & Stock Enhancement, No. 40 South Nongke Road, Luyang District, Hefei, 230031, Anhui, China.
| | - Haiyang Li
- Fisheries Research Institute, Anhui Academy of Agricultural Sciences, No. 40 South Nongke Road, Luyang District, Hefei, 230031, Anhui, China
- Anhui Province Key Laboratory of Aquaculture & Stock Enhancement, No. 40 South Nongke Road, Luyang District, Hefei, 230031, Anhui, China
| | - Xiaowu Chen
- Shanghai Ocean University, No.999 Huchenghuan Road, Nanhui New City, 201306, Shanghai, China
| | - Yangyang Jiang
- Fisheries Research Institute, Anhui Academy of Agricultural Sciences, No. 40 South Nongke Road, Luyang District, Hefei, 230031, Anhui, China
- Anhui Province Key Laboratory of Aquaculture & Stock Enhancement, No. 40 South Nongke Road, Luyang District, Hefei, 230031, Anhui, China
| | - Wei Jiang
- Fisheries Research Institute, Anhui Academy of Agricultural Sciences, No. 40 South Nongke Road, Luyang District, Hefei, 230031, Anhui, China
- Anhui Province Key Laboratory of Aquaculture & Stock Enhancement, No. 40 South Nongke Road, Luyang District, Hefei, 230031, Anhui, China
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10
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Dai J, Zhang L, Zhang P, Shu H, Mao A, Li Y. Ginsenoside Rg3 inhibits grass carp reovirus replication in grass carp ovarian epithelial cells. Microb Pathog 2020; 144:104174. [PMID: 32224212 DOI: 10.1016/j.micpath.2020.104174] [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: 12/06/2018] [Revised: 02/11/2020] [Accepted: 03/23/2020] [Indexed: 11/25/2022]
Abstract
Ginseng exhibits multiple medicinal properties, including the improvement of immune function and enhancing disease resistance. In this study, we investigated the inhibitory effects of ginsenoside Rg3 on grass carp reovirus (GCRV) infection of grass carp ovarian (CO) epithelial cells, in order to provide a baseline framework for future high-efficacy antiviral drug screening investigations. Ginsenoside Rg3 was added to GCRV-infected CO cells, and cells were cultured at 27 °C before cell proliferation was measured by MTT assays. Label-free real-time cellular analysis (RTCA) after 72 h of experimentation demonstrated that 100 μg/mL ginsenoside Rg3 treatment had the highest inhibitory effect on GCRV (among 1,10,100 μg/mL treatments). We then measured the capacity for cellular antioxidant ability. Cells treated with 1,10,100 μg/mL ginsenoside Rg3 exhibited increases in Total Antioxidant Capacity activity relative to controls, respectively. Furthermore, Antioxidant assay and reverse transcript quantitative polymerase chain reaction (RT-qPCR) showed that ginsenoside Rg3 were efficient to restrain the replication of GCRV in CO cells. Expression analysis of immune-related genes via RT-qPCR showed that treatment with ginsenoside Rg3 promoted expression of IRF-3 and IRF-7 increases, respectively. Moreover, expression of IFN-1 was induced, which then inhibition the expression of tumor necrosis factor-alpha (TNF-α). In conclusion, we demonstrated that ginsenoside Rg3 promotes CO cell proliferation, inhibits GCRV activity, promotes CO cell immune activities, and thereby enhances the resistance of CO to GCRV infection.
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Affiliation(s)
- Jing Dai
- College of Animal Science and Technology, Jilin Agricultural University, Changchun, 130118, China; College of Life Scienc, Jilin Agricultural University, Changchun, 130118, China
| | - Linbo Zhang
- College of Life Scienc, Jilin Agricultural University, Changchun, 130118, China
| | - Peijun Zhang
- Health Monitoring and Inspection Center of Jilin Province, 130062, China
| | - Hong Shu
- Tuberculosis Infection Hospital in Changchun, Jilin, 130113, China
| | - Anting Mao
- College of Animal Science and Technology, Jilin Agricultural University, Changchun, 130118, China
| | - Yuehong Li
- College of Animal Science and Technology, Jilin Agricultural University, Changchun, 130118, China.
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11
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Zhang F, Guo H, Chen Q, Ruan Z, Fang Q. Endosomes and Microtubles are Required for Productive Infection in Aquareovirus. Virol Sin 2019; 35:200-211. [PMID: 31858455 DOI: 10.1007/s12250-019-00178-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 09/18/2019] [Indexed: 12/20/2022] Open
Abstract
Grass carp reovirus (GCRV), the genus Aquareovirus in family Reoviridae, is viewed as the most pathogenic aquareovirus. To understand the molecular mechanism of how aquareovirus initiates productive infection, the roles of endosome and microtubule in cell entry of GCRV are investigated by using quantum dots (QDs)-tracking in combination with biochemical approaches. We found that GCRV infection and viral protein synthesis were significantly inhibited by pretreating host cells with endosome acidification inhibitors NH4Cl, chloroquine and bafilomycin A1 (Bafi). Confocal images indicated that GCRV particles could colocalize with Rab5, Rab7 and lysosomes in host cells. Further ultrastructural examination validated that viral particle was found in late endosomes. Moreover, disruption of microtubules with nocodazole clearly blocked GCRV entry, while no inhibitory effects were observed with cytochalasin D treated cells in viral infection, hinting that intracellular transportation of endocytic uptake in GCRV infected cells is via microtubules but not actin filament. Notably, viral particles were observed to transport along microtubules by using QD-labeled GCRV. Altogether, our results suggest that GCRV can use endosomes and microtubules to initiate productive infection.
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Affiliation(s)
- Fuxian Zhang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
- Wuhan Center for Animal Diseases Prevention and Control, Wuhan, 430071, China
| | - Hong Guo
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Qingxiu Chen
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Zheng Ruan
- Wuhan Center for Animal Diseases Prevention and Control, Wuhan, 430071, China
| | - Qin Fang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China.
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12
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Huang HW, Huang CH, Wen CM. Complete genome sequence and phylogenetic analysis of a novel aquareovirus isolated from a diseased marbled eel (Anguilla marmorata). Arch Virol 2019; 164:2585-2592. [PMID: 31377889 DOI: 10.1007/s00705-019-04365-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 07/07/2019] [Indexed: 11/25/2022]
Abstract
Marbled eel reovirus (MERV) is an aquareovirus (AQRV) isolated from diseased marbled eels (Anguilla marmorata) with petechial skin hemorrhage. In this study, we propagated MERV in a cell line derived from the brain of Aequidens rivulatus and purified viral particles by using a discontinuous cesium chloride gradient. Genomic RNA sequences were obtained through next-generation sequencing. MERV, similar to most other AQRVs, showed the presence of 11 double-stranded RNA segments encoding 12 proteins; however, the genome sequence displayed very little similarity to known AQRV sequences. Furthermore, the structural proteins of MERV were most closely related to American grass carp reovirus with sequence identity values of no more than 64.89%. Phylogenetic analysis based on the sequences of structural proteins indicated that MERV shows an evolutionary history between AQRV-B and -G, which belong to the saline and freshwater environment subgroups, respectively. We also observed that MERV showed a closer relationship to orthoreoviruses based on the protein sequences of NS38 and NS73. In summary, MERV is a novel AQRV that could be classified as a member of the new proposed AQRV species "Aquareovirus H". The taxonomic assignments and evolution of AQRVs thus warrant further investigation.
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Affiliation(s)
- Hui-Wen Huang
- Department of Life Sciences, National University of Kaohsiung, No. 700, Kaohsiung University Road, Nan-Tzu District, Kaohsiung, 81148, Taiwan
| | - Chiao-Hsuan Huang
- Department of Life Sciences, National University of Kaohsiung, No. 700, Kaohsiung University Road, Nan-Tzu District, Kaohsiung, 81148, Taiwan
| | - Chiu-Ming Wen
- Department of Life Sciences, National University of Kaohsiung, No. 700, Kaohsiung University Road, Nan-Tzu District, Kaohsiung, 81148, Taiwan.
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13
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Identification of a potential transcriptional regulator encoded by grass carp reovirus. Arch Virol 2019; 164:1393-1404. [DOI: 10.1007/s00705-019-04204-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 02/09/2019] [Indexed: 01/26/2023]
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14
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Zhang J, Guo H, Zhang F, Chen Q, Chang M, Fang Q. NS38 is required for aquareovirus replication via interaction with viral core proteins and host eIF3A. Virology 2019; 529:216-225. [DOI: 10.1016/j.virol.2019.01.029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 01/23/2019] [Accepted: 01/31/2019] [Indexed: 02/07/2023]
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15
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Zhang F, Yan S, Guo H, Chen Q, Fang Q. Characterization of viral entry and infection of quantum dot-labeled grass carp reovirus. Virol Sin 2018; 32:163-166. [PMID: 28466443 DOI: 10.1007/s12250-016-3903-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Affiliation(s)
- Fuxian Zhang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Shicui Yan
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Hong Guo
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Qingxiu Chen
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Qin Fang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China.
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16
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Structure of RNA polymerase complex and genome within a dsRNA virus provides insights into the mechanisms of transcription and assembly. Proc Natl Acad Sci U S A 2018; 115:7344-7349. [PMID: 29941585 DOI: 10.1073/pnas.1803885115] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Most double-stranded RNA (dsRNA) viruses transcribe RNA plus strands within a common innermost capsid shell. This process requires coordinated efforts by RNA-dependent RNA polymerase (RdRp) together with other capsid proteins and genomic RNA. Here we report the near-atomic resolution structure of the RdRp protein VP2 in complex with its cofactor protein VP4 and genomic RNA within an aquareovirus capsid using 200-kV cryoelectron microscopy and symmetry-mismatch reconstruction. The structure of these capsid proteins enabled us to observe the elaborate nonicosahedral structure within the double-layered icosahedral capsid. Our structure shows that the RdRp complex is anchored at the inner surface of the capsid shell and interacts with genomic dsRNA and four of the five asymmetrically arranged N termini of the capsid shell proteins under the fivefold axis, implying roles for these N termini in virus assembly. The binding site of the RNA end at VP2 is different from the RNA cap binding site identified in the crystal structure of orthoreovirus RdRp λ3, although the structures of VP2 and λ3 are almost identical. A loop, which was thought to separate the RNA template and transcript, interacts with an apical domain of the capsid shell protein, suggesting a mechanism for regulating RdRp replication and transcription. A conserved nucleoside triphosphate binding site was localized in our RdRp cofactor protein VP4 structure, and interactions between the VP4 and the genomic RNA were identified.
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17
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N-Terminal Myristoylated VP5 is Required for Penetrating Cell Membrane and Promoting Infectivity in Aquareoviruses. Virol Sin 2018; 33:287-290. [PMID: 29869748 DOI: 10.1007/s12250-018-0036-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 05/10/2018] [Indexed: 10/14/2022] Open
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18
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Ma J, Fan Y, Zhou Y, Liu W, Jiang N, Zhang J, Zeng L. Efficient resistance to grass carp reovirus infection in JAM-A knockout cells using CRISPR/Cas9. FISH & SHELLFISH IMMUNOLOGY 2018; 76:206-215. [PMID: 29477498 DOI: 10.1016/j.fsi.2018.02.039] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Revised: 02/13/2018] [Accepted: 02/19/2018] [Indexed: 06/08/2023]
Abstract
The hemorrhagic disease of grass carp (Ctenopharyngodon idellus) induced by grass carp reovirus (GCRV) leads to huge economic losses in China and currently, there are no effective methods available for prevention and treatment. The various GCRV genotypes may be one of the major obstacles in the pursuit of an effective antiviral treatment. In this study, we exploited CRISPR/Cas9 gene editing to specifically knockout the DNA sequence of the grass carp Junctional Adhesion Molecule-A (gcJAM-A) and evaluated in vitro resistance against various GCRV genotypes. Our results show that CRISPR/Cas9 effectively knocked out gcJAM-A and reduced GCRV infection for two different genotypes in permissive grass carp kidney cells (CIK), as evidenced by suppressed cytopathic effect (CPE) and GCRV progeny production in infected cells. In addition, with ectopic expression of gcJAM-A in cells, non-permissive cells derived from Chinese giant salamander (Andrias davidianus) muscle (GSM) could be highly infected by both GCRV-JX0901 and Hubei grass carp disease reovirus (HGDRV) strains that have different genotypes. Taken together, the results demonstrate that gcJAM-A is necessary for GCRV infection, implying a potential approach for viral control in aquaculture.
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Affiliation(s)
- Jie Ma
- Division of Fish Disease, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, Hubei, 430223, PR China.
| | - Yuding Fan
- Division of Fish Disease, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, Hubei, 430223, PR China.
| | - Yong Zhou
- Division of Fish Disease, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, Hubei, 430223, PR China.
| | - Wenzhi Liu
- Division of Fish Disease, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, Hubei, 430223, PR China.
| | - Nan Jiang
- Division of Fish Disease, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, Hubei, 430223, PR China.
| | - Jieming Zhang
- Division of Fish Disease, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, Hubei, 430223, PR China.
| | - Lingbing Zeng
- Division of Fish Disease, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, Hubei, 430223, PR China.
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19
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Targeting Heat Shock Protein 70 as an antiviral strategy against grass carp reovirus infection. Virus Res 2018; 247:1-9. [DOI: 10.1016/j.virusres.2018.01.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2017] [Revised: 12/08/2017] [Accepted: 01/12/2018] [Indexed: 01/08/2023]
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20
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Identification of the caveolae/raft-mediated endocytosis as the primary entry pathway for aquareovirus. Virology 2018; 513:195-207. [DOI: 10.1016/j.virol.2017.09.019] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 09/21/2017] [Accepted: 09/22/2017] [Indexed: 12/11/2022]
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21
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Liu W, Wang H, Yu F, Lu L. Grass carp reovirus outer capsid proteins VP5 and VP7 interact in vitro. Arch Virol 2017; 162:2375-2380. [DOI: 10.1007/s00705-017-3354-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2016] [Accepted: 03/04/2017] [Indexed: 10/19/2022]
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22
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Lu J, Li Y, Shen Z, Lu C, Lu L. TNF-α is involved in apoptosis triggered by grass carp reovirus infection in vitro. FISH & SHELLFISH IMMUNOLOGY 2016; 55:559-567. [PMID: 27346157 DOI: 10.1016/j.fsi.2016.06.033] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 06/13/2016] [Accepted: 06/22/2016] [Indexed: 06/06/2023]
Abstract
Grass carp reovirus (GCRV) infection causes apoptosis in Ctenopharyngodon idella kidney cells (CIK). However, the cause of GCRV-induced apoptosis and its signaling pathways remain unknown. This study investigated the role of TNF-α-induced capase-8 pathways in mediating GCRV-induced apoptosis in the grass carp (Ctenopharyngodon idella). Recombinant TNF-α was expressed and purified from Escherichia. coli. The western blot assay indicated that TNF-α expression level in kidney and spleen was higher than that in liver. In apoptosis assay, recombinant TNF-α triggered significant apoptosis in CIK cells, which was characterized by increased mRNA levels of TNF-α, TRADD or caspase-8, and enhanced caspase-8 activity in CIK cells. To confirm the biological activity of TNF-α during GCRV infection, significant apoptosis in CIK cells was induced by GCRV correlating with enhanced caspase-8 activity, increased mRNA level of TNF-α, TRADD or caspase-8, increased protein level of TNF-α in CIK cells and cell supernatant, suggesting that TNF-α-induced capase-8 pathways might be involved in GCRV-triggered apoptosis. Furthermore, treatment with an anti-TNF-α polyclonal antibody significantly decreased the degree of apoptosis in infected CIK cells compared with cells treated with a control antibody, which confirmed that TNF-α was a key mediator involved in GCRV-induced apoptosis. Taken together, these results indicated that GCRV might trigger apoptosis via TNF-α induced capase-8 pathways in CIK cells.
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Affiliation(s)
- Jianfei Lu
- Aquatic Pathogen Collection Center, MOA Key Laboratory of Freshwater Fishery Germplasm Resources, Shanghai Ocean University, Shanghai 201306, China
| | - Yan Li
- Aquatic Pathogen Collection Center, MOA Key Laboratory of Freshwater Fishery Germplasm Resources, Shanghai Ocean University, Shanghai 201306, China
| | - Zhaoyuan Shen
- Aquatic Pathogen Collection Center, MOA Key Laboratory of Freshwater Fishery Germplasm Resources, Shanghai Ocean University, Shanghai 201306, China
| | - Cuiyu Lu
- Aquatic Pathogen Collection Center, MOA Key Laboratory of Freshwater Fishery Germplasm Resources, Shanghai Ocean University, Shanghai 201306, China
| | - Liqun Lu
- Aquatic Pathogen Collection Center, MOA Key Laboratory of Freshwater Fishery Germplasm Resources, Shanghai Ocean University, Shanghai 201306, China.
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23
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Lu J, Wang H, Zhang Y, Li Y, Lu L. Grass carp reovirus NS26 interacts with cellular lipopolysaccharide-induced tumor necrosis factor-alpha factor, LITAF. Virus Genes 2016; 52:789-796. [PMID: 27405988 DOI: 10.1007/s11262-016-1370-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2016] [Accepted: 07/01/2016] [Indexed: 11/27/2022]
Abstract
The nonstructural protein NS26 of grass carp reovirus (GCRV) is encoded by the 11th genomic dsRNA segment, homolog of which is not found in orthoreoviruses. The role of NS26 in GCRV pathogenesis is still unclear. Previously, grass carp LITAF/SIMPLE protein was identified as a putative binding partner for NS26 in a yeast two-hybrid screen. Here, we further characterized the association between NS26 and LITAF using in vivo and in vitro protein interaction assays. Soluble GST-NS26 and His6-LITAF were expressed and purified from E. coli; recombinant NS26 tagged with myc and LITAF tagged with GFP were expressed in Ctenopharyngon idellus kidney cells (CIK) by transient transfection experiments. A GST pulldown assay demonstrated that GST-tagged NS26 efficiently bound to His6-LITAF. Co-immunoprecipitation assays demonstrated that GCRV NS26 reciprocally precipitated endogenous LITAF in CIK cells. Double-immunofluorescent analyses revealed myc-NS26 colocalized with GFP-LITAF in CIK cells. Taken together, the current in vitro and in vivo data demonstrated the interaction between cellular LITAF and GCRV NS26.
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Affiliation(s)
- Jianfei Lu
- Aquatic Pathogen Collection Center, MOA Key Laboratory of Freshwater Fishery Germplasm Resources, Shanghai Ocean University, Shanghai, 201306, China
| | - Hao Wang
- Aquatic Pathogen Collection Center, MOA Key Laboratory of Freshwater Fishery Germplasm Resources, Shanghai Ocean University, Shanghai, 201306, China
| | - Yanan Zhang
- Aquatic Pathogen Collection Center, MOA Key Laboratory of Freshwater Fishery Germplasm Resources, Shanghai Ocean University, Shanghai, 201306, China
| | - Yan Li
- Aquatic Pathogen Collection Center, MOA Key Laboratory of Freshwater Fishery Germplasm Resources, Shanghai Ocean University, Shanghai, 201306, China
| | - Liqun Lu
- Aquatic Pathogen Collection Center, MOA Key Laboratory of Freshwater Fishery Germplasm Resources, Shanghai Ocean University, Shanghai, 201306, China.
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24
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Chen Q, Zhang J, Zhang F, Guo H, Fang Q. Identification and characterization of two cleavage fragments from the Aquareovirus nonstructural protein NS80. Virol Sin 2016; 31:314-23. [PMID: 27279144 DOI: 10.1007/s12250-016-3723-7] [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: 01/11/2016] [Accepted: 05/05/2016] [Indexed: 10/21/2022] Open
Abstract
Aquareovirus species vary with respect to pathogenicity, and the nonstructural protein NS80 of aquareoviruses has been implicated in the regulation of viral replication and assembly, which can form viral inclusion bodies (VIBs) and recruit viral proteins to its VIBs in infected cells. NS80 consists of 742 amino acids with a molecular weight of approximately 80 kDa. Interestingly, a short specific fragment of NS80 has also been detected in infected cells. In this study, an approximately 58-kDa product of NS80 was confirmed in various infected and transfected cells by immunoblotting analyses using α-NS80C. Mutational analysis and time course expression assays indicated that the accumulation of the 58-kDa fragment was related to time and infection dose, suggesting that the fragment is not a transient intermediate of protein degradation. Moreover, another smaller fragment with a molecular mass of approximately 22 kDa was observed in transfected and infected cells by immunoblotting with a specific anti-FLAG monoclonal antibody or α-NS80N, indicating that the 58- kDa polypeptide is derived from a specific cleavage site near the amino terminus of NS80. Additionally, different subcellular localization patterns were observed for the 22-kDa and 58-kDa fragments in an immunofluorescence analysis, implying that the two cleavage fragments of NS80 function differently in the viral life cycle. These results provide a basis for additional studies of the role of NS80 played in replication and particle assembly of the Aquareovirus.
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Affiliation(s)
- Qingxiu Chen
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China.,University of the Chinese Academy of Sciences, Beijing, 100039, China
| | - Jie Zhang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Fuxian Zhang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Hong Guo
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Qin Fang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China.
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25
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The N-Terminal of Aquareovirus NS80 Is Required for Interacting with Viral Proteins and Viral Replication. PLoS One 2016; 11:e0148550. [PMID: 26871941 PMCID: PMC4752286 DOI: 10.1371/journal.pone.0148550] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 01/19/2016] [Indexed: 11/21/2022] Open
Abstract
Reovirus replication and assembly occurs within viral inclusion bodies that formed in specific intracellular compartments of cytoplasm in infected cells. Previous study indicated that aquareovirus NS80 is able to form inclusion bodies, and also can retain viral proteins within its inclusions. To better understand how NS80 performed in viral replication and assembly, the functional regions of NS80 associated with other viral proteins in aquareovirus replication were investigated in this study. Deletion mutational analysis and rotavirus NSP5-based protein association platform were used to detect association regions. Immunofluorescence images indicated that different N-terminal regions of NS80 could associate with viral proteins VP1, VP4, VP6 and NS38. Further co-immunoprecipitation analysis confirmed the interaction between VP1, VP4, VP6 or NS38 with different regions covering the N-terminal amino acid (aa, 1–471) of NS80, respectively. Moreover, removal of NS80 N-terminal sequences required for interaction with proteins VP1, VP4, VP6 or NS38 not only prevented the capacity of NS80 to support viral replication in NS80 shRNA-based replication complementation assays, but also inhibited the expression of aquareovirus proteins, suggesting that N-terminal regions of NS80 are necessary for viral replication. These results provided a foundational basis for further understanding the role of NS80 in viral replication and assembly during aquareovirus infection.
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26
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Laminin receptor is an interacting partner for viral outer capsid protein VP5 in grass carp reovirus infection. Virology 2016; 490:59-68. [PMID: 26848829 DOI: 10.1016/j.virol.2016.01.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Revised: 11/19/2015] [Accepted: 01/21/2016] [Indexed: 11/23/2022]
Abstract
Grass carp reovirus (GCRV) is responsible for viral hemorrhagic disease in cultured grass carp Ctenopharyngon idellus. Through yeast two-hybrid screen, laminin receptor (LamR) was identified as a potential interacting partner for the outer capsid protein VP5 of GCRV. We cloned and sequenced the gene encoding grass carp LamR. Viral attachment assay demonstrated the involvement of membrane-associated LamR in GCRV infection. Solid-phase overlay assays demonstrated that GCRV interacted with GST-tagged LamR in vitro. In contrast to VP7, GST-tagged VP5 was shown to associate with LamR in both pull-down and solid-phase blot overlay assays. With the reduction of LamR expression in CIK cells achieved by RNAi, remarkably reduced infection efficiency of GCRV was observed. CIK cells pretreated with polyclonal antibody against LamR resulted in dose-dependent inhibition of GCRV infection. These results collectively indicated that grass carp LamR was involved in GCRV infection by interacting with viral outer capsid protein VP5.
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27
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A Review of Intra- and Extracellular Antigen Delivery Systems for Virus Vaccines of Finfish. J Immunol Res 2015; 2015:960859. [PMID: 26065009 PMCID: PMC4433699 DOI: 10.1155/2015/960859] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 04/08/2015] [Accepted: 04/09/2015] [Indexed: 01/04/2023] Open
Abstract
Vaccine efficacy in aquaculture has for a long time depended on evaluating relative percent survival and antibody responses after vaccination. However, current advances in vaccine immunology show that the route in which antigens are delivered into cells is deterministic of the type of adaptive immune response evoked by vaccination. Antigens delivered by the intracellular route induce MHC-I restricted CD8+ responses while antigens presented through the extracellular route activate MHC-II restricted CD4+ responses implying that the route of antigen delivery is a conduit to induction of B- or T-cell immune responses. In finfish, different antigen delivery systems have been explored that include live, DNA, inactivated whole virus, fusion protein, virus-like particles, and subunit vaccines although mechanisms linking these delivery systems to protective immunity have not been studied in detail. Hence, in this review we provide a synopsis of different strategies used to administer viral antigens via the intra- or extracellular compartments. Further, we highlight the differences in immune responses induced by antigens processed by the endogenous route compared to exogenously processed antigens. Overall, we anticipate that the synopsis put together in this review will shed insights into limitations and successes of the current vaccination strategies used in finfish vaccinology.
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28
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Yan X, Xie J, Li J, Shuanghu C, Wu Z, Jian J. Screening and analysis on the protein interaction of the protein VP7 in grass carp reovirus. Virus Genes 2015; 50:425-33. [PMID: 25860999 DOI: 10.1007/s11262-015-1193-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2014] [Accepted: 11/06/2014] [Indexed: 12/26/2022]
Abstract
Grass carp reovirus (GCRV) has caused serious economic losses for several decades in China. The protein VP7 is one of the important structural proteins in GCRV. Recent studies indicated that the protein VP7 had the commendable antigenicity and immunogenicity. The protein VP7 cooperated with VP5 could change the conformation of the cell membrane and facilitate entry of GCRV into host cells. We speculated that the protein VP7 should play an important role in the pathogenesis of GCRV. In order to explore the function of the protein VP7, the bait protein expression plasmid pGBKT7-vp7 and the cDNA library of CIK cells were constructed. By yeast two-hybrid system, after multiple screening with the high screening rate medium, rotary verification, sequencing and bioinformatics analysis, the interactions of the protein VP7 with ribosomal protein S20 (RPS20) and eukaryotic translation initiation factor 3 subunit b (eIF3b) in CIK cells were identified. RPS20 played the important roles in the generation of influenza B virus and a variety of diseases. eIF3b was relative to the infection of some viruses. This study suggested that the protein VP7 played the role in viral replication and most likely interacted with host proteins by RPS20 and eIF3b. The interaction mechanisms of the protein VP7 with RPS20 and eIF3b, and the subsequent effector mechanisms needed to be further studied. The corresponding protein interaction of the protein VP7 was not acquired in bioinformatics. The protein VP7 and its untranslated region may have the unknown special function. This study laid the foundation for deeply exploring the function of the protein VP7 in GCRV and had the important scientific significance for exploring the pathogenic mechanism of GCRV.
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Affiliation(s)
- Xiuying Yan
- Guangdong Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Guangdong Ocean University, Huguangyan East, Zhanjiang, 524088, China,
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Yan S, Zhang J, Guo H, Yan L, Chen Q, Zhang F, Fang Q. VP5 autocleavage is required for efficient infection by in vitro-recoated aquareovirus particles. J Gen Virol 2015; 96:1795-800. [PMID: 25742690 DOI: 10.1099/vir.0.000116] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Grass carp reovirus (GCRV) is a member of the genus Aquareovirus in the family Reoviridae, and contains five core proteins (VP1-VP4 and VP6) and two outer-capsid proteins (VP5 and VP7) in its particle. Previous studies have revealed that the outer-capsid proteins of reovirus are responsible for initiating infection, but the mechanism is poorly understood. Using baculovirus-expressed VP5 and VP7 to recoat purified cores, in vitro assembly of GCRV was achieved in this study. Recoated GCRV (R-GCRV) closely resembled native GCRV (N-GCRV) in particle morphology, protein composition and infectivity. Similar to N-GCRV, the infectivity of R-GCRV could be inhibited by treating cells with the weak base NH4Cl. In addition, recoated particles carrying an Asn→Ala substitution at residue 42 of VP5 (VP5N42A/VP7 R-GCRV) were no longer infectious. These results provide strong evidence that autocleavage of VP5 is critical for aquareovirus to initiate efficient infection.
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Affiliation(s)
- Shicui Yan
- 1State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China 2University of Chinese Academy of Sciences, Beijing, PR China
| | - Jie Zhang
- 1State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China
| | - Hong Guo
- 1State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China
| | - Liming Yan
- 1State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China 2University of Chinese Academy of Sciences, Beijing, PR China
| | - Qingxiu Chen
- 1State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China 2University of Chinese Academy of Sciences, Beijing, PR China
| | - Fuxian Zhang
- 1State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China
| | - Qin Fang
- 1State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China
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Guo H, Chen Q, Yan L, Zhang J, Yan S, Zhang F, Fang Q. Identification of a functional motif in the AqRV NS26 protein required for enhancing the fusogenic activity of FAST protein NS16. J Gen Virol 2015; 96:1080-1085. [PMID: 25604927 DOI: 10.1099/vir.0.000057] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 01/14/2015] [Indexed: 11/18/2022] Open
Abstract
Aquareoviruses AqRVs have a close relationship with orthoreoviruses. However, they contain an additional genome segment, S11, which encodes nonstructural protein NS26. We previously showed that NS26 can enhance the fusogenic activity of the fusion-associated small transmembrane FAST protein NS16 from AqRV. In this study, a TLPK motif in NS26 was identified as being important for the enhancement. When the TLPK motif was deleted from NS26, the enhanced efficiency of the NS16-mediated cellcell fusion was significantly impaired. Further mutational analysis showed that the lysine K residue in the TLPK motif was critical for the enhancement. Additionally, deletion of the TLPK motif prevented NS26 from interacting with lysosomes. These findings suggested that the TLPK motif is important for NS26 to enhance the fusogenic activity of NS16, and NS26 may utilize the lysosome to benefit the fusion process.
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Affiliation(s)
- Hong Guo
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
| | - Qingxiu Chen
- University of the Chinese Academy of Sciences, Beijing 100039, China.,State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
| | - Liming Yan
- University of the Chinese Academy of Sciences, Beijing 100039, China.,State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
| | - Jie Zhang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
| | - Shicui Yan
- University of the Chinese Academy of Sciences, Beijing 100039, China.,State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
| | - Fuxian Zhang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
| | - Qin Fang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
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Xiao B, Chi X, Zhang L, Qu H, Liu Y, Wang X, Zhou J. Enhanced expression of GCRV VP6 in CIK cells by relative sequence optimization. Appl Biochem Biotechnol 2014; 173:2129-39. [PMID: 24928547 DOI: 10.1007/s12010-014-1012-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Accepted: 06/04/2014] [Indexed: 02/05/2023]
Abstract
Efficient expression of target protein is one of strategies for gene therapy or vaccine design. Many studies showed that codon optimization could enhance the expression of target proteins. In this paper, a target sequence of about 1.26 kb encoding the major capsid protein VP6 of grass carp reovirus (GCRV) and an optimized counterpart were synthesized and inserted into vectors for expressing VP6. The final constructs (named as pcDV6G and pcDV6YG) were transfected in Ctenopharyngodon idellus kidney (CIK) cells. The fluorescence analysis and the Western blot results showed that the gene fragment was transfected and expressed in CIK cells successfully. Although the qRT-PCR results showed no difference at the messenger RNA (mRNA) levels between the different versions of vp6 in the indicated stages, the enzyme-linked immunosorbent assay (ELISA) results showed that the protein level of VP6 expressed by pcDV6YG was higher than that by pcDV6G in the indicated hours. Taken together, these results suggest that the enhanced expression of GCRV VP6 in CIK cells by relative sequence optimization may be a good choice for making DNA vaccine against GCRV.
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Affiliation(s)
- Bo Xiao
- School of Life Sciences, Ludong University, 264025, Yantai, Shandong Province, People's Republic of China,
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Yan L, Liu H, Li X, Fang Q. The VP2 protein of grass carp reovirus (GCRV) expressed in a baculovirus exhibits RNA polymerase activity. Virol Sin 2014; 29:86-93. [PMID: 24643934 DOI: 10.1007/s12250-014-3366-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2013] [Accepted: 01/03/2014] [Indexed: 10/25/2022] Open
Abstract
The double-shelled grass carp reovirus (GCRV) is capable of endogenous RNA transcription and processing. Genome sequence analysis has revealed that the protein VP2, encoded by gene segment 2 (S2), is the putative RNA-dependent RNA polymerase (RdRp). In previous work, we have ex-pressed the functional region of VP2 that is associated with RNA polymerase activity (denoted as rVP2(390-900)) in E. coli and have prepared a polyclonal antibody against VP2. To characterize the GCRV RNA polymerase, a recombinant full-length VP2 (rVP2) was first constructed and expressed in a baculovirus system, as a fusion protein with an attached His-tag. Immunofluorescence (IF) assays, together with immunoblot (IB) analyses from both expressed cell extracts and purified Histagged rVP2, showed that rVP2 was successfully expressed in Sf9 cells. Further characterization of the replicase activity showed that purified rVP2 and GCRV particles exhibited poly(C)-dependent poly(G) polymerase activity. The RNA enzymatic activity required the divalent cation Mg(2+), and was optimal at 28 °C. The results provide a foundation for further studies on the RNA polymerases of aquareoviruses during viral transcription and replication.
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Affiliation(s)
- Liming Yan
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
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Zhou Y, Fan YD, Zeng LB. Construction of a recombinant eukaryotic vector for a grass carp reovirus VP6 gene and its expression in vitro and in vivo. Virusdisease 2014; 25:69-77. [PMID: 24426312 PMCID: PMC3889242 DOI: 10.1007/s13337-013-0176-6] [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: 07/21/2013] [Accepted: 10/29/2013] [Indexed: 12/24/2022] Open
Abstract
A recombinant plasmid expressing the VP6 inner capsid coding gene of grass carp reovirus (GCRV) was constructed and expressed in a Ctenopharyngodon idellus kidney (CIK) cell line and grass carps. The VP6 gene was amplified by RT-PCR, cloned into a pEGFP-N1 eukaryotic expression vector and transfected into CIK cells. Results from enhanced green fluorescent protein (EGFP) experiments and flow cytometry showed highest protein expression at 48 h. The immunoreactivity of fusion protein was confirmed using an indirect immunofluorescent assay. The specific binding between the fusion protein and polyclonal mouse GCRV VP6-specific antiserum indicated that the fusion protein was translated in vitro and had good immunogenicity. An antiviral activity assay showed that the virus titer was 100-fold lower in the GCRV VP6 expressed cells than in the pEGFP-N1 transfected cells. The expression levels of three immune genes in the head kidney of grass carps injected with the recombinant plasmid were used. Mx, TLR3 and IgM mRNA expression increased sharply at the 1st and 15th days post-injection (dpi). Specific antibodies were detected 30 days after vaccination. Neutralizing titers of the antibodies in vaccinated fish detected ranged from 160 to 320. Intramuscular injection of grass carps with 1 μg of pEGFP-N1-VP6 was found to provide strong protection against GCRV. These results suggested that the VP6 gene was a good candidate for the design of GCRV-DNA vaccines and to investigate the use of cytokines as co-stimulatory molecules.
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Affiliation(s)
- Yong Zhou
- Division of Fish Disease, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, 430223 People’s Republic of China
| | - Yu-ding Fan
- Division of Fish Disease, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, 430223 People’s Republic of China
| | - Ling-bing Zeng
- Division of Fish Disease, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, 430223 People’s Republic of China
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High-resolution 3D structures reveal the biological functions of reoviruses. Virol Sin 2013; 28:318-25. [PMID: 24254888 DOI: 10.1007/s12250-013-3341-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2013] [Accepted: 09/30/2013] [Indexed: 02/07/2023] Open
Abstract
Viruses in the family Reoviridae are non-enveloped particles comprising a segmented double-stranded RNA genome surrounded by a two-layered or multi-layered icosahedral protein capsid. These viruses are classified into two sub-families based on their particle structural organization. Recent studies have focused on high-resolution three-dimensional structures of reovirus particles by using cryo-electron microscopy (cryo-EM) to approach the resolutions seen in X-ray crystallographic structures. The results of cryo-EM image reconstructions allow tracing of most of the protein side chains, and thus permit integration of structural and functional information into a coherent mechanism for reovirus assembly and entry.
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Detection of grass carp reovirus (GCRV) with monoclonal antibodies. Arch Virol 2013; 159:649-55. [DOI: 10.1007/s00705-013-1864-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Accepted: 08/27/2013] [Indexed: 10/26/2022]
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Jian JC, Wang Y, Yan XY, Ding Y, Wu ZH, Lu YS. Molecular cloning and prokaryotic expression of vp5 gene of grass carp reovirus strain GCRV096. Virus Genes 2013; 47:483-9. [PMID: 23943413 DOI: 10.1007/s11262-013-0967-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Accepted: 07/29/2013] [Indexed: 11/27/2022]
Abstract
VP5 is an outer capsid protein of grass carp reovirus (GCRV). It is predicted to involve in helping GCRV enter the host cells. In this study, the full-length vp5 gene (accession number in GenBank: JN206664.1) was cloned from GCRV strain GCRV096, which was isolated from diseased grass carp (Ctenopharyngodon idella) in southern China by RT-PCR technique using the primers designed from the known vp5 gene sequences of other strains of GCRV published in GenBank. The ORF sequence of vp5 is composed of 1,947 nucleotides encoding a 648-residues protein with a calculated molecular mass of 68.6 kDa and an estimated isoelectric point of 6.1. Sequence analysis results showed that VP5 might serve as a penetration protein and play an important role in GCRV penetration into the host cells. A full length of vp5 gene was subcloned into the prokaryotic expression vector pET-28a (+) and the recombinant plasmid (pET/GCRV-VP5) was then transduced into Escherichia coli BL21 (DE3) cells to express VP5 in vitro. SDS-PAGE and western blotting analysis indicated that the protein expressed successfully. Results also showed that the fusion protein expressed in the form of inclusion body, and it expressed in the highest level when induced with 0.2-mM IPTG at 28 °C for 4 h. These results are important for the future study on the molecular structure, function, and immunogenicity of GCRV capsid protein.
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Affiliation(s)
- Ji-chang Jian
- Key Laboratory of Pathogen Biology and Epidemiology of Aquatic Economic Animals of Guangdong Province, Guangdong Ocean University, Zhanjiang, 524025, China
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Wang T, Li J, Lu L. Quantitative in vivo and in vitro characterization of co-infection by two genetically distant grass carp reoviruses. J Gen Virol 2013; 94:1301-1309. [DOI: 10.1099/vir.0.049965-0] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Grass carp reovirus (GCRV) is one of the most serious pathogens threatening grass carp (Ctenopharyngodon idella) production in China. Through sequence analysis, the co-existence of two genetically distant grass carp reoviruses, named GCRV-JX01 and GCRV-JX02, was revealed in the same diseased grass carp sample collected in 2011. GCRV-JX01 and GCRV-JX02 shared high levels of homology with GCRV-873 and GCRV-GD108, respectively. In contrast to GCRV-JX01, GCRV-JX02 induced no cytopathic effect in infected cells. A quantitative real-time PCR assay was employed to monitor the replication efficiency of both virus strains in either Ctenopharyngodon idella kidney (CIK) cells or infected cell supernatant. The results demonstrated that, although GCRV-JX02 did reduce the cellular replication level of GCRV-JX01 up to 10-fold during co-infection, there was no significant impact on the productive virus progeny level in supernatant compared to that of cells infected by GCRV-JX01 alone. To validate the hypothesis that both viruses might co-infect grass carp without significant interference in the field, we collected clinical samples from two different fish farms in 2012 and monitored virus loads for each fish. The data showed that 55 % of the collected fish samples were co-infected by GCRV-JX01 and GCRV-JX02, and the single virus infection rate was 10 % for GCRV-JX01 and 20 % for GCRV-JX02. For both viruses, the in vivo viral loads under co-infection and single viral infection were similar. No serological cross-reaction or cross-protection occurred between GCRV-JX01 and JX02 in our immunization and challenge tests. This new information on co-infection by two genetically distant virus strains should be helpful for designing vaccines targeting the causative agents of grass carp haemorrhagic disease.
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Affiliation(s)
- Tu Wang
- Key Laboratory of Aquatic Genetic Resources of the Ministry of Agriculture, Shanghai Ocean University, 201306, PR China
| | - Jiale Li
- Key Laboratory of Aquatic Genetic Resources of the Ministry of Agriculture, Shanghai Ocean University, 201306, PR China
| | - Liqun Lu
- Key Laboratory of Aquatic Genetic Resources of the Ministry of Agriculture, Shanghai Ocean University, 201306, PR China
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Wen D, Yan L, Shao L, Guo H, Li X, Fang Q. Aquareovirus protein VP6 colocalizes with NS80 protein in infected and transfected cells. Virol J 2013; 10:133. [PMID: 23622425 PMCID: PMC3660289 DOI: 10.1186/1743-422x-10-133] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Accepted: 04/25/2013] [Indexed: 01/08/2023] Open
Abstract
Background Aquareovirus particle is comprised of central core and outer capsid, which is built by seven structural proteins (VP1-VP7). The protein VP6 has been identified to be a clamp protein of stabilizing inner core frame VP3, and bridging outer shell protein VP5. However, the biological properties of VP6 in viral life cycle remain unknown. Results The recombinant VP6 (rVP6) of aquareovirus was expressed in E. coli, and the polyclonal antibody against VP6 was generated by using purified rVP6 in this study. Following the preparation of VP6 antibody, the VP6 component in aquareovirus infected cells and purified viral particles was detected by Immunoblotting (IB) assay. Furthermore, using Immunofluorescence (IF) microscopy, singly transfected VP6 protein was observed to exhibit a diffuse distribution mainly in the cytoplasm, while it appeared inclusion phenotype in infected cells. Meanwhile, inclusion structures were also identified when VP6 was coexpressed with nonstructural protein NS80 in cotransfected cells. Conclusions VP6 can be recruited by NS80 to its inclusions in both infected and transfected cells. The colocalization of VP6 and NS80 is corresponding to their homologous proteins σ2 and μNS in MRV. Our results suggest that VP6 may play a significant role in viral replication and particle assembly.
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Affiliation(s)
- Dawei Wen
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
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Shao L, Guo H, Yan LM, Liu H, Fang Q. Aquareovirus NS80 recruits viral proteins to its inclusions, and its C-terminal domain is the primary driving force for viral inclusion formation. PLoS One 2013; 8:e55334. [PMID: 23424630 PMCID: PMC3570539 DOI: 10.1371/journal.pone.0055334] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Accepted: 12/20/2012] [Indexed: 12/30/2022] Open
Abstract
Cytoplasmic inclusion bodies formed in reovirus-infected cells are the sites of viral replication and assembly. Previous studies have suggested that the NS80 protein of aquareovirus may be involved in the formation of viral inclusion bodies. However, it remains unknown whether other viral proteins are involved in the process, and what regions of NS80 may act coordinately in mediating inclusion formation. Here, we observed that globular cytoplasmic inclusions were formed in virus-infected cells and viral proteins NS80 and NS38 colocalized in the inclusions. During transfection, singly expressed NS80 could form cytoplasmic inclusions and recruit NS38 and GFP-tagged VP4 to these structures. Further treatment of cells with nocodazole, a microtubule inhibitor, did not disrupt the inclusion, suggesting that inclusion formation does not rely on microtubule network. Besides, we identified that the region 530–742 of NS80 was likely the minimal region required for inclusion formation, and the C-tail, coiled-coil region as well as the conserved linker region were essential for inclusion phenotype. Moreover, with series deletions from the N-terminus, a stepwise conversion occurred from large condensed cytoplasmic to small nuclear inclusions, then to a diffused intracellular distribution. Notablely, we found that the nuclear inclusions, formed by NS80 truncations (471 to 513–742), colocalized with cellular protein β-catenin. These data indicated that NS80 could be a major mediator in recruiting NS38 and VP4 into inclusion structures, and the C-terminus of NS80 is responsible for inclusion formation.
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Affiliation(s)
- Ling Shao
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Hong Guo
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Li-Ming Yan
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Huan Liu
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Qin Fang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
- * E-mail:
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Chen C, Sun X, Liao L, Luo S, Li Z, Zhang X, Wang Y, Guo Q, Fang Q, Dai H. Antigenic analysis of grass carp reovirus using single-chain variable fragment antibody against IgM from Ctenopharyngodon idella. SCIENCE CHINA-LIFE SCIENCES 2013; 56:59-65. [DOI: 10.1007/s11427-012-4425-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Accepted: 11/28/2012] [Indexed: 10/27/2022]
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Yan L, Guo H, Sun X, Shao L, Fang Q. Characterization of grass carp reovirus minor core protein VP4. Virol J 2012; 9:89. [PMID: 22559058 PMCID: PMC3390282 DOI: 10.1186/1743-422x-9-89] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Accepted: 05/04/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Grass Carp Reovirus (GCRV), a tentative member in the genus Aquareovirus of family Reoviridae, contains eleven segmented (double-stranded RNA) dsRNA genome which encodes 12 proteins. A low-copy core component protein VP4, encoded by the viral genome segment 5(S5), has been suggested to play a key role in viral genome transcription and replication. RESULTS To understand the role of minor core protein VP4 played in molecular pathogenesis during GCRV infection, the recombinant GCRV VP4 gene was constructed and expressed in both prokaryotic and mammalian cells in this investigation. The recombinant His-tag fusion VP4 products expressed in E.coli were identified by Western blotting utilizing His-tag specific monoclonal and GCRV polyclonal antibodies. In addition, the expression of VP4 in GCRV infected cells, appeared in granules structure concentrated mainly in the cytoplasm, can be detected by Immunofluorescence (IF) using prepared anti-VP4 polyclonal antibody. Meanwhile, VP4 protein in GCRV core and infected cell lysate was identified by Immunoblotting (IB) assay. Of particular note, the VP4 protein was exhibited a diffuse distribution in the cytoplasm and nucleus in transfected cells, suggesting that VP4 protein may play a partial role in the nucleus by regulating cell cycle besides its predicted cytoplasmic function in GCRV infection. CONCLUSIONS Our results indicate the VP4 is a core component in GCRV. The cellular localization of VP4 is correlated with its predicted function. The data provide a foundation for further studies aimed at understanding the role of VP4 in viroplasmic inclusion bodies (VIB) formation during GCRV replication and assembly.
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Affiliation(s)
- Liming Yan
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
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Shao L, Sun X, Fang Q. Antibodies against outer-capsid proteins of grass carp reovirus expressed in E. coli are capable of neutralizing viral infectivity. Virol J 2011; 8:347. [PMID: 21745413 PMCID: PMC3149003 DOI: 10.1186/1743-422x-8-347] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Accepted: 07/12/2011] [Indexed: 01/28/2023] Open
Abstract
Background Grass carp reovirus (GCRV), which causes severe infectious outbreaks of hemorrhagic disease in aquatic animals, is a highly pathogenic agent in the Aquareovirus genus of family Reoviridae. The outer capsid shell of GCRV, composed of the VP5-VP7 protein complex, is believed to be involved in cell entry. The objective of this study was to produce a major neutralization antibody for mitigating GCRV infection. Results Recombinant plasmids of GCRV outer capsid proteins VP5 and VP7 were constructed and expressed in prokaryotic cells in our previous work. In this study, we prepared GCRV Antibody (Ab), VP5Ab and VP7Ab generated from purified native GCRV, recombinant VP5 and VP7 respectively. Immunoblotting analysis showed that the prepared antibodies were specific to its antigens. In addition, combined plaque and cytopathic effect (CPE)-based TCID50 (50% tissue culture infective dose) assays showed that both VP5Ab and VP7Ab were capable of neutralizing viral infectivity. Particularly, the neutralizing activity of VP7Ab was 3 times higher than that of VP5Ab, suggesting that VP7 might be a dominating epitope. Moreover, the combination of VP5Ab and VP7Ab appeared to enhance GCRV neutralizing capacity. Conclusions The results presented in this study indicated that VP7 protein was the major epitope of GCRV. Furthermore, VP5Ab and VP7Ab in combination presented an enhanced capacity to neutralize the GCRV particle, suggesting that the VP5 and VP7 proteins may cooperate with each other during virus cell entry. The data can be used not only to further define the surface epitope domain of GCRV but may also be applicable in the designing of vaccines.
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Affiliation(s)
- Ling Shao
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
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Cai L, Sun X, Shao L, Fang Q. Functional investigation of grass carp reovirus nonstructural protein NS80. Virol J 2011; 8:168. [PMID: 21489306 PMCID: PMC3101161 DOI: 10.1186/1743-422x-8-168] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2011] [Accepted: 04/14/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Grass Carp Reovirus (GCRV), a highly virulent agent of aquatic animals, has an eleven segmented dsRNA genome encased in a multilayered capsid shell, which encodes twelve proteins including seven structural proteins (VP1-VP7), and five nonstructural proteins (NS80, NS38, NS31, NS26, and NS16). It has been suggested that the protein NS80 plays an important role in the viral replication cycle that is similar to that of its homologous protein μNS in the genus of Orthoreovirus. RESULTS As a step to understanding the basis of the part played by NS80 in GCRV replication and particle assembly, we used the yeast two-hybrid (Y2H) system to identify NS80 interactions with proteins NS38, VP4, and VP6 as well as NS80 and NS38 self-interactions, while no interactions appeared in the four protein pairs NS38-VP4, NS38-VP6, VP4-VP4, and VP4-VP6. Bioinformatic analyses of NS80 with its corresponding proteins were performed with all currently available homologous protein sequences in ARVs (avian reoviruses) and MRVs (mammalian reoviruses) to predict further potential functional domains of NS80 that are related to VFLS (viral factory-like structures) formation and other roles in viral replication. Two conserved regions spanning from aa (amino acid) residues of 388 to 433, and 562 to 580 were discovered in this study. The second conserved region with corresponding conserved residues Tyr565, His569, Cys571, Asn573, and Glu576 located between the two coiled-coils regions (aa ~513-550 and aa ~615-690) in carboxyl-proximal terminus were supposed to be essential to form VFLS, so that aa residues ranging from 513 to 742 of NS80 was inferred to be the smallest region that is necessary for forming VFLS. The function of the first conserved region including Ala395, Gly419, Asp421, Pro422, Leu438, and Leu443 residues is unclear, but one-third of the amino-terminal region might be species specific, dominating interactions with other viral components. CONCLUSIONS Our results in this study together with those from previous investigations indicate the protein NS80 might play a central role in VFLS formation and viral components recruitment in GCRV particle assembly, similar to the μNS protein in ARVs and MRVs.
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Affiliation(s)
- Lin Cai
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
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Zhang L, Luo Q, Fang Q, Wang Y. An improved RT-PCR assay for rapid and sensitive detection of grass carp reovirus. J Virol Methods 2010; 169:28-33. [DOI: 10.1016/j.jviromet.2010.06.009] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2010] [Revised: 06/07/2010] [Accepted: 06/17/2010] [Indexed: 11/24/2022]
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Fan C, Shao L, Fang Q. Characterization of the nonstructural protein NS80 of grass carp reovirus. Arch Virol 2010; 155:1755-63. [PMID: 20640908 DOI: 10.1007/s00705-010-0753-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2010] [Accepted: 07/07/2010] [Indexed: 11/28/2022]
Abstract
Nonstructural proteins of members of the family Reoviridae are believed to play significant roles in the virus replication cycle. Phylogenetic analyses indicate that the nonstructural protein NS80 of grass carp reovirus, encoded by a gene of Segment 4 (S4), is a primary determinant that is related to the formation of viroplasmic inclusion bodies (VIB), where viral replication and assembly are thought to occur. To understand the role of the NS80 protein in viral replication, an initial investigation of NS80 gene expression in both infected and transfected cells was conducted. Transmission electron microscopy results indicate that replication and assembly of GCRV occur within VIB-like structures in the perinuclear region of the cell cytoplasm. Furthermore, expression of the S4 gene in infected cells was detected with an NS80-specific antibody by western blot and immunofluorescence. Moreover, globular VIB-like structures were observed when expressing GFP-derived full-length NS80 (pEGFP-C1/NS80) and recombinants containing the C-terminal conserved region (pEGFP-C1/NS80₃₃₅₋₇₂₄) in transfected Vero. No such structures were detected in cells transfected with an N-terminal recombinant (pEGFP-C1/NS80₁₋₃₃₄), suggesting that the NS80 C-terminal conserved region may be involved in the formation of inclusion structures. These data provide a foundation for further functional studies of NS80 related to viral inclusion formation in viral replication.
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Affiliation(s)
- Chao Fan
- Wuhan Institute of Virology, Chinese Academy of Sciences, China
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Zhang X, Jin L, Fang Q, Hui WH, Zhou ZH. 3.3 A cryo-EM structure of a nonenveloped virus reveals a priming mechanism for cell entry. Cell 2010; 141:472-82. [PMID: 20398923 DOI: 10.1016/j.cell.2010.03.041] [Citation(s) in RCA: 207] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2009] [Revised: 01/22/2010] [Accepted: 03/29/2010] [Indexed: 12/30/2022]
Abstract
To achieve cell entry, many nonenveloped viruses must transform from a dormant to a primed state. In contrast to the membrane fusion mechanism of enveloped viruses (e.g., influenza virus), this membrane penetration mechanism is poorly understood. Here, using single-particle cryo-electron microscopy, we report a 3.3 A structure of the primed, infectious subvirion particle of aquareovirus. The density map reveals side-chain densities of all types of amino acids (except glycine), enabling construction of a full-atom model of the viral particle. Our structure and biochemical results show that priming involves autocleavage of the membrane penetration protein and suggest that Lys84 and Glu76 may facilitate this autocleavage in a nucleophilic attack. We observe a myristoyl group, covalently linked to the N terminus of the penetration protein and embedded in a hydrophobic pocket. These results suggest a well-orchestrated process of nonenveloped virus entry involving autocleavage of the penetration protein prior to exposure of its membrane-insertion finger.
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Affiliation(s)
- Xing Zhang
- Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095-7364, USA
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Shao L, Fan C, Maj E, Fang Q. Molecular characterization of nonstructural protein NS38 of grass carp reovirus. Virol Sin 2010; 25:123-9. [PMID: 20960309 DOI: 10.1007/s12250-010-3115-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2009] [Accepted: 01/22/2010] [Indexed: 10/19/2022] Open
Abstract
Viral nonstructural proteins in both enveloped and non-enveloped viruses play important roles in viral replication. Protein NS38 of Grass carp reovirus (GCRV), has been deduced to be a non-structural protein, and, consistent with other reoviruses, is considered to cooperate with the NS80 protein in viral particle assembly. To investigate the molecular basis of the role of NS38, a complete protein was expressed in E.coli for the first time. It was found that there is a better expression of NS38 induced with IPTG at 28 °C rather than 37 °C. In addition, the antiserum of NS38 prepared with purified fusion protein and injected into rabbit could be used for detecting NS38 protein expression in GCRV infected cell lysate, while there is not any reaction crossed with purified virus particle, confirming NS38 is not a component of the viral structural protein. The result reported in this study will provide evidence for further viral protein-protein and protein-RNA interaction in dsRNA viruses replication.
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Affiliation(s)
- Ling Shao
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
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Cheng L, Zhu J, Hui WH, Zhang X, Honig B, Fang Q, Zhou ZH. Backbone model of an aquareovirus virion by cryo-electron microscopy and bioinformatics. J Mol Biol 2009; 397:852-63. [PMID: 20036256 DOI: 10.1016/j.jmb.2009.12.027] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2009] [Revised: 12/07/2009] [Accepted: 12/15/2009] [Indexed: 01/05/2023]
Abstract
Grass carp reovirus (GCRV) is a member of the aquareovirus genus in the Reoviridae family and has a capsid with two shells-a transcription-competent core surrounded by a coat. We report a near-atomic-resolution reconstruction of the GCRV virion by cryo-electron microscopy and single-particle reconstruction. A backbone model of the GCRV virion, including seven conformers of the five capsid proteins making up the 1500 molecules in both the core and the coat, was derived using cryo-electron microscopy density-map-constrained homology modeling and refinement. Our structure clearly showed that the amino-terminal segment of core protein VP3B forms an approximately 120-A-long alpha-helix-rich extension bridging across the icosahedral 2-fold-symmetry-related molecular interface. The presence of this unique structure across this interface and the lack of an external cementing molecule at this location in GCRV suggest a stabilizing role of this extended amino-terminal density. Moreover, part of this amino-terminal extension becomes invisible in the reconstruction of transcription-competent core particles, suggesting its involvement in endogenous viral RNA transcription. Our structure of the VP1 turret represents its open state, and comparison with its related structures at the closed state suggests hinge-like domain movements associated with the mRNA-capping machinery. Overall, this first backbone model of an aquareovirus virion provides a wealth of structural information for understanding the structural basis of GCRV assembly and transcription.
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Affiliation(s)
- Lingpeng Cheng
- Department of Microbiology, Immunology and Molecular Genetics, University of California at Los Angeles, Los Angeles, CA 90095-7364, USA
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Expression of outer capsid protein VP5 of grass carp reovirus in E.coli and analysis of its immunogenicity. Virol Sin 2009. [DOI: 10.1007/s12250-009-3038-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Fan C, Zhang LL, Lei CF, Fang Q. Expression and identification of inclusion forming-related domain of NS80 nonstructural protein of grass carp reovirus. Virol Sin 2009. [DOI: 10.1007/s12250-009-3028-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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